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Saito A, Omura I, Imaizumi K. CREB3L1/OASIS: cell cycle regulator and tumor suppressor. FEBS J 2024. [PMID: 38215153 DOI: 10.1111/febs.17052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/09/2023] [Accepted: 01/05/2024] [Indexed: 01/14/2024]
Abstract
Cell cycle checkpoints detect DNA errors, eventually arresting the cell cycle to promote DNA repair. Failure of such cell cycle arrest causes aberrant cell proliferation, promoting the pathogenesis of multiple diseases, including cancer. Endoplasmic reticulum (ER) stress transducers activate the unfolded protein response, which not only deals with unfolded proteins in ER lumen but also orchestrates diverse physiological phenomena such as cell differentiation and lipid metabolism. Among ER stress transducers, cyclic AMP-responsive element-binding protein 3-like protein 1 (CREB3L1) [also known as old astrocyte specifically induced substance (OASIS)] is an ER-resident transmembrane transcription factor. This molecule is cleaved by regulated intramembrane proteolysis, followed by activation as a transcription factor. OASIS is preferentially expressed in specific cells, including astrocytes and osteoblasts, to regulate their differentiation. In accordance with its name, OASIS was originally identified as being upregulated in long-term-cultured astrocytes undergoing cell cycle arrest because of replicative stress. In the context of cell cycle regulation, previously unknown physiological roles of OASIS have been discovered. OASIS is activated as a transcription factor in response to DNA damage to induce p21-mediated cell cycle arrest. Although p21 is directly induced by the master regulator of the cell cycle, p53, no crosstalk occurs between p21 induction by OASIS or p53. Here, we summarize previously unknown cell cycle regulation by ER-resident transcription factor OASIS, particularly focusing on commonalities and differences in cell cycle arrest between OASIS and p53. This review also mentions tumorigenesis caused by OASIS dysfunctions, and OASIS's potential as a tumor suppressor and therapeutic target.
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Affiliation(s)
- Atsushi Saito
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Japan
| | - Issei Omura
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, Japan
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Legartová S, Fagherazzi P, Goswami P, Brazda V, Lochmanová G, Koutná I, Bártová E. Irradiation potentiates p53 phosphorylation and p53 binding to the promoter and coding region of the TP53 gene. Biochimie 2023; 204:154-168. [PMID: 36167255 DOI: 10.1016/j.biochi.2022.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/08/2022] [Accepted: 09/21/2022] [Indexed: 01/12/2023]
Abstract
An essential factor of the DNA damage response is 53BP1, a multimeric protein that inhibits the resection-dependent double-strand break (DBS) repair. The p53 protein is a tumor suppressor known as a guardian of the genome. Although the interaction between 53BP1 and its p53 partner is well-known in regulating gene expression, a question remains whether genome injury can affect the interaction between 53BP1 and p53 proteins or p53 binding to DNA. Here, using mass spectrometry, we determine post-translational modifications and interaction properties of 53BP1 and p53 proteins in non-irradiated and γ-irradiated cells. In addition, we used Atomic Force Microscopy (AFM) and Fluorescent Lifetime Imaging Microscopy combined with Fluorescence Resonance Energy Transfer (FLIM-FRET) for studies of p53 binding to DNA. Also, we used local laser microirradiation as a tool of advanced confocal microscopy, showing selected protein accumulation at locally induced DNA lesions. We observed that 53BP1 and p53 proteins accumulate at microirradiated chromatin but with distinct kinetics. The density of 53BP1 (53BP1pS1778) phosphorylated form was lower in DNA lesions than in the non-specified form. By mass spectrometry, we found 22 phosphorylations, 4 acetylation sites, and methylation of arginine 1355 within the DNA-binding domain of the 53BP1 protein (aa1219-1711). The p53 protein was phosphorylated on 8 amino acids and acetylated on the N-terminal domain. Post-translational modifications (PTMs) of 53BP1 were not changed in cells exposed to γ-radiation, while γ-rays increased the level of S6ph and S15ph in p53. Interaction analysis showed that 53BP1 and p53 proteins have 54 identical interaction protein partners, and AFM revealed that p53 binds to both non-specific and TP53-specific sequences (AGACATGCCTA GGCATGTCT). Irradiation by γ-rays enhanced the density of the p53 protein at the AGACATGCCTAGGCATGTCT region, and the binding of p53 S15ph to the TP53 promoter was potentiated in irradiated cells. These findings show that γ-irradiation, in general, strengthens the binding of phosphorylated p53 protein to the encoding gene.
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Affiliation(s)
- Soňa Legartová
- Department of Cell Biology and Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic.
| | - Paolo Fagherazzi
- Department of Cell Biology and Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic.
| | - Pratik Goswami
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic; National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic.
| | - Vaclav Brazda
- Department of Biophysical Chemistry and Molecular Oncology, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic.
| | - Gabriela Lochmanová
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic; National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic.
| | - Irena Koutná
- The International Clinical Research Center of St. Anne's University Hospital in Brno (FNUSA-ICRC), Pekařská 53, 656 91, Brno, Czech Republic
| | - Eva Bártová
- Department of Cell Biology and Epigenetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, Brno, Czech Republic.
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Chen YC, Young MJ, Chang HP, Liu CY, Lee CC, Tseng YL, Wang YC, Chang WC, Hung JJ. Estradiol-mediated inhibition of DNMT1 decreases p53 expression to induce M2-macrophage polarization in lung cancer progression. Oncogenesis 2022; 11:25. [PMID: 35589688 PMCID: PMC9119954 DOI: 10.1038/s41389-022-00397-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 04/07/2022] [Accepted: 04/12/2022] [Indexed: 11/11/2022] Open
Abstract
Previous studies indicate that estrogen positively regulates lung cancer progression. Understanding the reasons will be beneficial for treating women with lung cancer in the future. In this study, we found that tumor formation was more significant in female EGFRL858R mice than in male mice. P53 expression levels were downregulated in the estradiol (E2)-treated lung cancer cells, female mice with EGFRL858R-induced lung cancer mice, and premenopausal women with lung cancer. E2 increased DNA methyltransferase 1 (DNMT1) expression to enhance methylation in the TP53 promoter, which led to the downregulation of p53. Overexpression of GFP-p53 decreased DNMT1 expression in lung cancer cells. TP53 knockout in mice with EGFRL858R-induced lung cancer not only changed gene expression in cancer cells but also increased the polarization of M2 macrophages by increasing C–C motif chemokine ligand 5 (CCL5) expression and decreasing growth differentiation factor 15 (GDF15) expression. The TP53 mutation rate was increased in females with late-stage but not early-stage lung cancer compared to males with lung cancer. In conclusion, E2-induced DNMT1 and p53 expression were negatively regulated each other in females with lung cancer, which not only affected cancer cells but also modulated the tumor-associated microenvironment, ultimately leading to a poor prognosis.
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Affiliation(s)
- Yung-Ching Chen
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Ming-Jer Young
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Hui-Ping Chang
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Yu Liu
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Chi Lee
- Division of Thoracic Surgery, Department of Surgery, College of Medicine National Cheng Kung University, Tainan, Taiwan
| | - Yau-Lin Tseng
- Division of Thoracic Surgery, Department of Surgery, College of Medicine National Cheng Kung University, Tainan, Taiwan
| | - Yi-Ching Wang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chang Chang
- The Ph.D. Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Jan-Jong Hung
- Department of Biotechnology and Bioindustry Sciences, National Cheng Kung University, Tainan, Taiwan. .,Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan.
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Joshi S, Garlapati C, Aneja R. Epigenetic Determinants of Racial Disparity in Breast Cancer: Looking beyond Genetic Alterations. Cancers (Basel) 2022; 14:cancers14081903. [PMID: 35454810 PMCID: PMC9025441 DOI: 10.3390/cancers14081903] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/03/2022] [Accepted: 04/04/2022] [Indexed: 12/10/2022] Open
Abstract
Simple Summary A substantial disparity in breast cancer incidence and mortality exists between African American (AA) and European American (EA) women. However, the basis for these disparities is poorly understood. In this article, we describe that gene–environment interactions mediated through epigenetic modifications may play a significant role in racial disparities in BC incidence and outcomes. Our in silico analyses and an in-depth literature survey suggest that there exists a significant difference in epigenetic patterns between AA and EA women with breast cancer. Herein, we describe the environmental factors that contribute to these epigenetic changes, which may underlie the disparate racial burden in patients with breast cancer. We suggest that AA women with higher basal epigenetic changes, may have higher pre-disposition to cancer onset, and an aggressive disease course. Pre-existing racial differences in epigenetic profiles of breast tissues raises the possibility of examining these profiles for early diagnosis. Abstract Breast cancer (BC) is the most commonly diagnosed cancer in women. Despite advancements in BC screening, prevention, and treatment, BC incidence and mortality remain high among African American (AA) women. Compared with European American (EA) women, AA women tend to be diagnosed with more advanced and aggressive tumors and exhibit worse survival outcomes. Most studies investigating the determinants of racial disparities in BC have focused on genetic factors associated with African ancestry. However, various environmental and social stressors over an individual’s life course can also shape racial stratification in BC. These social and environmental exposures result in long-term changes in gene expression mediated by epigenetic mechanisms. Epigenetics is often portrayed as an intersection of socially patterned stress and genetic expression. The enduring nature of epigenetic changes makes them suitable for studying the effects of different environmental exposures over an individual’s life course on gene expression. The role of differential social and environmental exposures in racial disparities in BC suggests varied epigenetic profiles or signatures associated with specific BC subtypes in AA and EA women. These epigenetic profiles in EA and AA women could be used as biomarkers for early BC diagnosis and disease prognosis and may prove valuable for the development of targeted therapies for BC. This review article discusses the current state of knowledge regarding epigenetic differences between AA and EA women with BC. We also discuss the role of socio-environmental factors, including psychosocial stress, environmental toxicants, and dietary factors, in delineating the different epigenetic profiles in AA and EA patients with BC.
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Affiliation(s)
- Shriya Joshi
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA; (S.J.); (C.G.)
| | | | - Ritu Aneja
- Department of Biology, Georgia State University, Atlanta, GA 30303, USA; (S.J.); (C.G.)
- Department of Clinical and Diagnostics Sciences, School of Health Professions, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Correspondence: or
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Abstract
With approximately 38 million people living with HIV/AIDS globally, and a further 1.5 million new global infections per year, it is imperative that we advance our understanding of all factors contributing to HIV infection. While most studies have focused on the influence of host genetic factors on HIV pathogenesis, epigenetic factors are gaining attention. Epigenetics involves alterations in gene expression without altering the DNA sequence. DNA methylation is a critical epigenetic mechanism that influences both viral and host factors. This review has five focal points, which examines (i) fluctuations in the expression of methylation modifying factors upon HIV infection (ii) the effect of DNA methylation on HIV viral genes and (iii) host genome (iv) inferences from other infectious and non-communicable diseases, we provide a list of HIV-associated host genes that are regulated by methylation in other disease models (v) the potential of DNA methylation as an epi-therapeutic strategy and biomarker. DNA methylation has also been shown to serve as a robust therapeutic strategy and precision medicine biomarker against diseases such as cancer and autoimmune conditions. Despite new drugs being discovered for HIV, drug resistance is a problem in high disease burden settings such as Sub-Saharan Africa. Furthermore, genetic therapies that are under investigation are irreversible and may have off target effects. Alternative therapies that are nongenetic are essential. In this review, we discuss the potential role of DNA methylation as a novel therapeutic intervention against HIV.
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Affiliation(s)
- Thilona Arumugam
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Upasana Ramphal
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), School of Laboratory Medicine & Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Theolan Adimulam
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Romona Chinniah
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Veron Ramsuran
- School of Laboratory Medicine and Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), School of Laboratory Medicine & Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
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Sriraman A, Debnath TK, Xhemalce B, Miller KM. Making it or breaking it: DNA methylation and genome integrity. Essays Biochem 2020; 64:687-703. [PMID: 32808652 DOI: 10.1042/EBC20200009] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/22/2020] [Accepted: 07/29/2020] [Indexed: 12/11/2022]
Abstract
Cells encounter a multitude of external and internal stress-causing agents that can ultimately lead to DNA damage, mutations and disease. A cascade of signaling events counters these challenges to DNA, which is termed as the DNA damage response (DDR). The DDR preserves genome integrity by engaging appropriate repair pathways, while also coordinating cell cycle and/or apoptotic responses. Although many of the protein components in the DDR are identified, how chemical modifications to DNA impact the DDR is poorly understood. This review focuses on our current understanding of DNA methylation in maintaining genome integrity in mammalian cells. DNA methylation is a reversible epigenetic mark, which has been implicated in DNA damage signaling, repair and replication. Sites of DNA methylation can trigger mutations, which are drivers of human diseases including cancer. Indeed, alterations in DNA methylation are associated with increased susceptibility to tumorigenesis but whether this occurs through effects on the DDR, transcriptional responses or both is not entirely clear. Here, we also highlight epigenetic drugs currently in use as therapeutics that target DNA methylation pathways and discuss their effects in the context of the DDR. Finally, we pose unanswered questions regarding the interplay between DNA methylation, transcription and the DDR, positing the potential coordinated efforts of these pathways in genome integrity. While the impact of DNA methylation on gene regulation is widely understood, how this modification contributes to genome instability and mutations, either directly or indirectly, and the potential therapeutic opportunities in targeting DNA methylation pathways in cancer remain active areas of investigation.
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Abstract
Significant reprogramming of epigenome is widely described during pathogenesis of breast cancer. Transformation of normal cell to hyperplastic cell and to neoplastic phenotype is associated with aberrant DNA (de)methylation, which, through promoter and enhancer methylation changes, activates oncogenes and silence tumor suppressor genes in variety of tumors including breast. DNA methylation, one of the major epigenetic mechanisms is catalyzed by evolutionarily conserved isoforms namely, DNMT1, DNMT3A and DNMT3B in humans. Over the years, studies have demonstrated intricate and complex regulation of DNMT isoforms at transcriptional, translational and post-translational levels. The recent findings of allosteric regulation of DNMT isoforms and regulation by other interacting chromatin modifying proteins emphasizes functional integrity and their contribution for the development of breast cancer and progression. DNMT isoforms are regulated by several intrinsic and extrinsic parameters. In the present review, we have extensively performed bioinformatics analysis of expression of DNMT isoforms along with their transcriptional and post-transcriptional regulators such as transcription factors, interacting proteins, hormones, cytokines and dietary elements along with their significance during pathogenesis of breast tumors. Our review manuscript provides a comprehensive understanding of key factors regulating DNMT isoforms in breast tumor pathology and documents unsolved issues.
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Affiliation(s)
- Mangala Hegde
- Manipal School of Life Sciences, Manipal Academy of Higher Education, Planetarium Complex, Manipal, 576104, India
| | - Manjunath B Joshi
- Manipal School of Life Sciences, Manipal Academy of Higher Education, Planetarium Complex, Manipal, 576104, India.
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Hameed Y, Ejaz S. Integrative analysis of multi-omics data highlighted TP53 as a potential diagnostic and prognostic biomarker of survival in breast invasive carcinoma patients. Comput Biol Chem 2021; 92:107457. [PMID: 33610131 DOI: 10.1016/j.compbiolchem.2021.107457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 02/04/2021] [Accepted: 02/06/2021] [Indexed: 11/15/2022]
Abstract
The global incidence of breast invasive carcinoma (BRIC) has risen significantly in recent years, so it is important to identify the novel biomarkers for the early detection and treatment of BRIC. The role of the TP53 gene is well studied in the pathogenesis of BRIC but still, observations are conflicting. Therefore, this study was initiated to have a consolidated overview of TP53 contributions in the BRIC initiation and progression by analyzing its mutatome, expression variations, promoter methylation level, clinical outcome, and drug sensitivity analysis in BRIC using cBioPortal, UALCAN, KM plotter, and CCLE GDSC toolkit database. Mutatome analysis revealed that TP53 was mutated in 30 % BRIC cases and among all the noted mutations, missense and truncation mutation were noticed as the most frequent mutations and thought to be involved in the up-regulation of TP53 expression. TP53 transcription, translation, and promoter methylation levels in BRIC patients of various clinicopathological features were high relative to the normal controls. Kaplan Meier overall survival (OS) analysis revealed a good prognostic value of TP53 overexpression for the survival in BRIC patients. Moreover, TP53 overexpression was found to alter the effectiveness of various drugs used in the chemotherapy of BRIC. Collectively, our findings suggested that TP53 might be a potential diagnostic and prognostic marker for the survival in BRIC patients of various clinicopathological features.
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Affiliation(s)
- Yasir Hameed
- Institute of Biochemistry, Biotechnology and Bioinformatics, The Islamia University of Bahawalpur, Pakistan.
| | - Samina Ejaz
- Institute of Biochemistry, Biotechnology and Bioinformatics, The Islamia University of Bahawalpur, Pakistan.
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Fabianowska-Majewska K, Kaufman-Szymczyk A, Szymanska-Kolba A, Jakubik J, Majewski G, Lubecka K. Curcumin from Turmeric Rhizome: A Potential Modulator of DNA Methylation Machinery in Breast Cancer Inhibition. Nutrients 2021; 13:332. [PMID: 33498667 DOI: 10.3390/nu13020332] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/12/2021] [Accepted: 01/19/2021] [Indexed: 12/24/2022] Open
Abstract
One of the most systematically studied bioactive nutraceuticals for its benefits in the management of various diseases is the turmeric-derived compounds: curcumin. Turmeric obtained from the rhizome of a perennial herb Curcuma longa L. is a condiment commonly used in our diet. Curcumin is well known for its potential role in inhibiting cancer by targeting epigenetic machinery, with DNA methylation at the forefront. The dynamic DNA methylation processes serve as an adaptive mechanism to a wide variety of environmental factors, including diet. Every healthy tissue has a precise DNA methylation pattern that changes during cancer development, forming a cancer-specific design. Hypermethylation of tumor suppressor genes, global DNA demethylation, and promoter hypomethylation of oncogenes and prometastatic genes are hallmarks of nearly all types of cancer, including breast cancer. Curcumin has been shown to modulate epigenetic events that are dysregulated in cancer cells and possess the potential to prevent cancer or enhance the effects of conventional anti-cancer therapy. Although mechanisms underlying curcumin-mediated changes in the epigenome remain to be fully elucidated, the mode of action targeting both hypermethylated and hypomethylated genes in cancer is promising for cancer chemoprevention. This review provides a comprehensive discussion of potential epigenetic mechanisms of curcumin in reversing altered patterns of DNA methylation in breast cancer that is the most commonly diagnosed cancer and the leading cause of cancer death among females worldwide. Insight into the other bioactive components of turmeric rhizome as potential epigenetic modifiers has been indicated as well.
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Ghazi T, Nagiah S, Chuturgoon AA. Fusaric acid decreases p53 expression by altering promoter methylation and m6A RNA methylation in human hepatocellular carcinoma (HepG2) cells. Epigenetics 2021; 16:79-91. [PMID: 32631113 PMCID: PMC7889137 DOI: 10.1080/15592294.2020.1788324] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/08/2020] [Accepted: 06/02/2020] [Indexed: 12/20/2022] Open
Abstract
Fusaric acid (FA) is a food-borne mycotoxin that mediates toxicity with limited information on its epigenetic properties. p53 is a tumour suppressor protein that regulates cell cycle arrest and apoptotic cell death. The expression of p53 is regulated transcriptionally by promoter methylation and post-transcriptionally by N-6-methyladenosine (m6A) RNA methylation. We investigated the effect of FA on p53 expression and its epigenetic regulation via promoter methylation and m6A RNA methylation in human hepatocellular carcinoma (HepG2) cells. HepG2 cells were treated with FA [0, 25, 50, 104, and 150 µg/ml; 24 h] and thereafter, DNA, RNA, and protein was isolated. Promoter methylation and expression of p53 was measured using qPCR and Western blot. RNA immuno-precipitation was used to determine m6A-p53 levels. The expression of m6A methyltransferases (METTL3 and METTL14), demethylases (FTO and ALKBH5), and readers (YTHDF1-3 and YTHDC2) were measured using qPCR. FA induced p53 promoter hypermethylation (p < 0.0001) and decreased p53 expression (p < 0.0001). FA decreased m6A-p53 levels (p < 0.0001) by decreasing METTL3 (p < 0.0001) and METTL14 (p < 0.0001); and suppressed expression of YTHDF1 (p < 0.0001), YTHDF3 (p < 0.0001), and YTHDC2 (p < 0.0001) that ultimately reduced p53 translation (p < 0.0001). Taken together, the data shows that FA epigenetically decreased p53 expression by altering its promoter methylation and m6A RNA methylation in HepG2 cells. This study reveals a mechanism for p53 regulation by FA and provides insight into future therapeutic interventions.
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Affiliation(s)
- Terisha Ghazi
- Discipline of Medical Biochemistry and Chemical Pathology, School of Laboratory Medicine and Medical Science, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Savania Nagiah
- Discipline of Medical Biochemistry and Chemical Pathology, School of Laboratory Medicine and Medical Science, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
| | - Anil A. Chuturgoon
- Discipline of Medical Biochemistry and Chemical Pathology, School of Laboratory Medicine and Medical Science, College of Health Sciences, Howard College Campus, University of KwaZulu-Natal, Durban, South Africa
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Neja SA. Site-Specific DNA Demethylation as a Potential Target for Cancer Epigenetic Therapy. Epigenet Insights 2020; 13:2516865720964808. [PMID: 35036833 PMCID: PMC8756105 DOI: 10.1177/2516865720964808] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 09/13/2020] [Indexed: 12/13/2022] Open
Abstract
Aberrant promoter DNA hypermethylation is a typical characteristic of cancer and it is often seen in malignancies. Recent studies showed that regulatory cis-elements found up-stream of many tumor suppressor gene promoter CpG island (CGI) attract DNA methyltransferases (DNMT) that hypermethylates and silence the genes. As epigenetic alterations are potentially reversible, they make attractive targets for therapeutic intervention. The currently used decitabine (DAC) and azacitidine (AZA) are DNMT inhibitors that follow the passive demethylation pathway. However, they lead to genome-wide demethylation of CpGs in cells, which makes difficult to use it for causal effect analysis and treatment of specific epimutations. Demethylation through specific demethylase enzymes is thus critical for epigenetic resetting of silenced genes and modified chromatins. Yet DNA-binding factors likely play a major role to guide the candidate demethylase enzymes upon its fusion. Before the advent of clustered regulatory interspaced short palindromic repeats (CRISPR), both zinc finger proteins (ZNFs) and transcription activator-like effector protein (TALEs) were used as binding platforms for ten-eleven translocation (TET) enzymes and both systems were able to induce transcription at targeted loci in an in vitro as well as in vivo model. Consequently, the development of site-specific and active demethylation molecular trackers becomes more than hypothetical to makes a big difference in the treatment of cancer in the future. This review is thus to recap the novel albeit distinct studies on the potential use of site-specific demethylation for the development of epigenetic based cancer therapy.
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Wang S, Pan D, Su M, Huang G, Sun G. Moderately high folate level may offset the effects of aberrant DNA methylation of P16 and P53 genes in esophageal squamous cell carcinoma and precancerous lesions. Genes Nutr 2020; 15:18. [PMID: 32993492 PMCID: PMC7526188 DOI: 10.1186/s12263-020-00677-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/17/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND This study evaluated gene-nutrition interactions between folate and the aberrant DNA methylation of tumor suppressor genes in different stages of carcinogenesis of esophageal squamous cell carcinoma (ESCC). METHODS Two hundred ESCC cases, 200 esophageal precancerous lesion (EPL) cases, and 200 controls matched by age (± 2 years) and gender were used for this study. Baseline data and dietary intake information was collected via questionnaire. The serum folate levels and methylation status of promoter regions of p16 and p53 were detected. RESULTS The interactions of increased serum folate level with unmethylated p16 and p53 promoter regions were significantly associated with a reduced risk of both EPL and ESCC (p for interaction < 0.05). The interactions of the lowest quartile of serum folate level with p16 or p53 methylation was significantly associated with an increased risk of ESCC (OR = 2.96, 95% CI, 1.45-6.05; OR = 2.34, 95% CI, 1.15-4.75). An increased serum folate level was also related to a decreasing trend of EPL and ESCC risks when p16 or p53 methylation occurred. The interaction of spinach, Chinese cabbage, liver and bean intake with unmethylated p16 and p53 was significantly associated with a reduced risk of EPL or ESCC (p for interaction < 0.05). CONCLUSIONS The interactions between a high folate level and unmethylated p16 and p53 promoter regions may have a strong preventive effect on esophageal carcinogenesis. Additionally, a high folate level may offset the tumor-promoting effects of aberrant DNA methylation of the genes, but it is also noteworthy that a very high level of folate may not have a protective effect on EPL in some cases.
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Affiliation(s)
- Shaokang Wang
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009, P. R. China.
| | - Da Pan
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009, P. R. China
| | - Ming Su
- Huai'an District Center for Disease Control and Prevention, Huai'an, 223200, P. R. China
| | - Guiling Huang
- Jiangsu Research Center for Primary Health Development and General Practice Education, Jiangsu Vocational College of Medicine, Yancheng, 224005, P. R. China
| | - Guiju Sun
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009, P. R. China
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13
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Khan MA, Tiwari D, Dongre A, Sadaf, Mustafa S, Das CR, Massey S, Bose PD, Bose S, Husain SA. Exploring the p53 connection of cervical cancer pathogenesis involving north-east Indian patients. PLoS One 2020; 15:e0238500. [PMID: 32976537 PMCID: PMC7518589 DOI: 10.1371/journal.pone.0238500] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 06/20/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND As per WHO, Cervical cancer (CaCx) is a global issue, being the fourth common cancer in women with incidence rate of 13.1 per 1 lakh women globally and accounting for 311000 deaths in the year 2018 itself globally. The molecular pathogenesis in Human papillomavirus (HPV) infected cases is inconclusive. The detection of molecular factors leading to progression of CaCx can be important in the diagnosis and management of the disease. p53 a known tumor suppressor gene having a regulative role in cell cycle has been highlighted as key factor in the prevention of cancer but its significance in CaCx cases has been variably documented. The present study therefore targeted to evaluate the significance of p53 profile in CaCx cases in ethnically distinct northeast Indian population. METHODS Blood and Tissue samples (N = 85) of cervical cancer patients were collected and screening for HPV was performed using PCR. Thereafter the differential mRNA expression(qPCR), Immunohistochemistry, Mutation (PCR direct sequencing method) of p53 was studied. Further p53 epigenetic profiling was done by Methylation specific PCR (MS-PCR) and western blotting by using p53 acetylation specific antibodies. RESULTS Our findings revealed that the downregulation of p53 was associated with the progression of disease and the variation in downregulation based on p53 polymorphism was observed. Further hypermethylation and deacetylation of p53 was also found to be associated with the pathogenesis of CaCx. The downregulated expression and hypermethylation of p53 in lower grade of CaCx, together established its association with the progression of CaCx from lower to severe grade. CONCLUSION Therefore, in CaCx patients of northeast Indian population, malfunctioning of p53 is found to have significant role in cervical cancer progression.
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Affiliation(s)
- Mohammad Aasif Khan
- Human Genetics Laboratory, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Diptika Tiwari
- Department of Biotechnology, Gauhati University, Guwahati, Assam, India
| | - Anita Dongre
- Human Genetics Laboratory, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Sadaf
- Human Genetics Laboratory, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Saad Mustafa
- Human Genetics Laboratory, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Chandana Ray Das
- Department of Obstetrics & Gynecology, Gauhati Medical College and Hospital, Guwahati, Assam, India
| | - Sheersh Massey
- Human Genetics Laboratory, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
| | - Purabi Deka Bose
- Department of Molecular Biology and Biotechnology, Cotton University, Guwahati, Assam, India
| | - Sujoy Bose
- Department of Biotechnology, Gauhati University, Guwahati, Assam, India
| | - Syed Akhtar Husain
- Human Genetics Laboratory, Department of Biosciences, Jamia Millia Islamia, New Delhi, India
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Abstract
Cancer is a disease of global epigenetic dysregulation. Mutations in epigenetic regulators are common events in multiple cancer types and epigenetic therapies are emerging as a treatment option in several malignancies. A major challenge for the clinical management of cancer is the heterogeneous nature of this disease. Cancers are composed of numerous cell types and evolve over time. This heterogeneity confounds decisions regarding treatment and promotes disease relapse. The emergence of single-cell epigenomic technologies has introduced the exciting possibility of linking genetic and transcriptional heterogeneity in the context of cancer biology. The next challenge is to leverage these tools for improved patient outcomes. Here we consider how single-cell epigenomic technologies may address the current challenges faced by cancer clinicians.
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Affiliation(s)
- Danielle R Bond
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, University of Newcastle, Callaghan 2308, New South Wales, Australia
| | - Kumar Uddipto
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, University of Newcastle, Callaghan 2308, New South Wales, Australia
| | - Anoop K Enjeti
- Department of Haematology, Calvary Mater Newcastle, Waratah 2298, New South Wales, Australia.,School of Medicine & Public Health, Faculty of Health & Medicine, University of Newcastle, Callaghan 2308, New South Wales, Australia.,NSW Health Pathology - Hunter, New Lambton Heights 2305, New South Wales, Australia
| | - Heather J Lee
- School of Biomedical Sciences & Pharmacy, Faculty of Health & Medicine, University of Newcastle, Callaghan 2308, New South Wales, Australia
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Zeng F, Heng J, Guo X, Wang Y, Wu W, Tang L, Chen M, Wang S, Deng H, Wang J. The novel TP53 3'-end methylation pattern associated with its expression would be a potential biomarker for breast cancer detection. Breast Cancer Res Treat 2020; 180:237-245. [PMID: 31983017 DOI: 10.1007/s10549-020-05536-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 01/14/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Deficiency or silence of TP53 is an early event in breast tumorigenesis. Aberrant methylation and mutation in regulatory regions were considered as crucial regulators of gene expression. METHODS Using multiplex-PCR and next-generation sequencing technology, we analyzed TP53 mutation spectrum in its promoter region. Using PCR target sequence enrichment and next-generation bisulfite sequencing technology, we analyzed the methylation profile of the promoter and 3'-end regions of TP53 gene in paired breast tumor and normal tissues from 120 breast cancer patients. The expression of TP53 and the flanking gene ATP1B2 was explored with qPCR method in the same cohort. RESULTS No promoter mutation of TP53 gene was found in the cohort of the 120 breast cancer patients. The 3'-end of TP53 gene was hyper-methylated (average 78.71%) compared with the promoter region (average less than 1%) in breast tumor tissues. TP53 was significantly lower expressed (P = 1.68E-15) and hyper-methylated in 3'-end (P = 1.82E-18) in tumor. Negative cis correlation was found between the TP53 expression and its 3'-end methylation (P = 9.02E-8, R = 0.337). TP53 expression was significantly associated with PR status (P = 0.0128), Ki67 level (P = 0.0091), and breast cancer subtypes (P = 0.0109). TP53 3'-end methylation and expression showed a good performance in discriminating breast cancer and normal tissues with an AUC of 0.930. CONCLUSIONS The 3'-end methylation of TP53 might be a crucial regulator for its expression in breast cancer, suggesting that TP53 3'-end hyper-methylation associated with its lower expression could be a potential biomarker for breast cancer diagnosis.
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Affiliation(s)
- Feng Zeng
- Department of Emergency, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Jianfu Heng
- Hunan Cancer Hospital, Affiliated Cancer Hospital of Xiangya School of Medicine, Changsha, 410013, China
- School of Life Sciences, Central South University, Changsha, 410013, Hunan, China
| | - Xinwu Guo
- Sansure Biotech Inc., Changsha, 410205, Hunan, China
| | - Yue Wang
- School of Life Sciences, Central South University, Changsha, 410013, Hunan, China
| | - Wenhan Wu
- School of Life Sciences, Central South University, Changsha, 410013, Hunan, China
| | - Lili Tang
- Department of Breast Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Min Chen
- Sansure Biotech Inc., Changsha, 410205, Hunan, China
| | - Shouman Wang
- Department of Breast Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Hongyu Deng
- Hunan Cancer Hospital, Affiliated Cancer Hospital of Xiangya School of Medicine, Changsha, 410013, China
| | - Jun Wang
- School of Life Sciences, Central South University, Changsha, 410013, Hunan, China.
- Sansure Biotech Inc., Changsha, 410205, Hunan, China.
- Center for Molecular Medicine, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
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Pan D, Su M, Huang G, Luo P, Zhang T, Fu L, Wei J, Wang S, Sun G. MTHFR C677T genetic polymorphism in combination with serum vitamin B 2, B 12 and aberrant DNA methylation of P16 and P53 genes in esophageal squamous cell carcinoma and esophageal precancerous lesions: a case-control study. Cancer Cell Int 2019; 19:288. [PMID: 31754346 PMCID: PMC6852963 DOI: 10.1186/s12935-019-1012-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 11/01/2019] [Indexed: 02/06/2023] Open
Abstract
Background The study aimed to explore the associations between the interactions of serum vitamin B2 or B12 levels, aberrant DNA methylation of p16 or p53 and MTHFR C677T polymorphism and the risks of esophageal squamous cell carcinoma (ESCC) and esophageal precancerous lesion (EPL). Methods 200 ESCC cases, 200 EPL cases and 200 normal controls were matched by age (± 2 years) and gender. Serum vitamin B2 and B12 levels, MTHFR C677T genetic polymorphisms and the methylation status of genes were assessed. Chi square test, one-way analysis of variance and binary logistic regression were performed. Results The lowest quartile of both serum vitamin B2 and B12 with TT genotype showed significant increased EPL risk (OR = 4.91, 95% CI 1.31-18.35; OR = 6.88, 95% CI 1.10-42.80). The highest quartile of both serum vitamin B2 and B12 with CC genotype showed significant decreased ESCC risk (OR = 0.16, 95% CI 0.04-0.60; OR = 0.10, 95% CI 0.02-0.46). The ORs of p16 methylation for genotype CT and TT were 1.98 (95% CI 1.01-3.89) and 17.79 (95% CI 2.26-140.22) in EPL, 4.86 (95% CI 2.48-9.50) and 20.40 (95% CI 2.53-164.81) in ESCC, respectively. Similarly, p53 methylation with genotype TT was associated with increased EPL and ESCC risks (OR = 13.28, 95% CI 1.67-105.70; OR = 15.24, 95% CI 1.90-122.62). Conclusions The MTHFR C677T genotype and serum vitamin B2 or B12 levels may interact in ways which associated with the EPL and ESCC risks. The gene-gene interaction suggested that aberrant DNA methyaltion of either p16 or p53 combined with T alleles of MTHFR was associated with increased risks of both EPL and ESCC.
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Affiliation(s)
- Da Pan
- 1Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009 People's Republic of China
| | - Ming Su
- Huai'an District Center for Disease Control and Prevention, Huai'an, 223200 People's Republic of China
| | - Guiling Huang
- 3Jiangsu Vocational College of Medicine, Yancheng, 224005 People's Republic of China
| | - Pengfei Luo
- 4Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, 210009 People's Republic of China
| | - Ting Zhang
- 1Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009 People's Republic of China
| | - Lingmeng Fu
- 1Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009 People's Republic of China
| | - Jie Wei
- 1Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009 People's Republic of China
| | - Shaokang Wang
- 1Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009 People's Republic of China
| | - Guiju Sun
- 1Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, 210009 People's Republic of China
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Ma B, Huang Z, Wang Q, Zhang J, Zhou B, Wu J. Integrative analysis of genetic and epigenetic profiling of lung squamous cell carcinoma (LSCC) patients to identify smoking level relevant biomarkers. BioData Min 2019; 12:18. [PMID: 31641374 PMCID: PMC6802182 DOI: 10.1186/s13040-019-0207-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 09/12/2019] [Indexed: 12/12/2022] Open
Abstract
Background Incidence and mortality of lung cancer have dramatically decreased during the last decades, yet still approximately 160,000 deaths per year occurred in United States. Smoking intensity, duration, starting age, as well as environmental cofactors including air-pollution, showed strong association with major types of lung cancer. Lung squamous cell carcinoma is a subtype of non-small cell lung cancer, which represents 25% of the cases. Thus, exploring the molecular pathogenic mechanisms of lung squamous cell carcinoma plays crucial roles in lung cancer clinical diagnosis and therapy. Results In this study, we performed integrative analyses on 299 comparative datasets of RNA-seq and methylation data, collected from 513 lung squamous cell carcinoma cases in The Cancer Genome Atlas. The data were divided into high and low smoking groups based on smoking intensity (Numbers of packs per year). We identified 1002 significantly up-regulated genes and 534 significantly down-regulated genes, and explored their cellular functions and signaling pathways by bioconductor packages GOseq and KEGG. Global methylation status was analyzed and visualized in circular plot by CIRCOS. RNA-and methylation data were correlatively analyzed, and 24 unique genes were identified, for further investigation of regional CpG sites' interactive patterns by bioconductor package coMET. AIRE, PENK, and SLC6A3 were the top 3 genes in the high and low smoking groups with significant differences. Conclusions Gene functions and DNA methylation patterns of these 24 genes are important and useful in disclosing the differences of gene expression and methylation profiling caused by different smoking levels.
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Affiliation(s)
- Bidong Ma
- Department of Medical Oncology, Zhe Jiang Chinese Medicine University affiliated Chinese Medicine Hospital, Wen Zhou, Zhe Jiang province People's Republic of China
| | - Zhiyou Huang
- Department of Medical Oncology, Zhe Jiang Chinese Medicine University affiliated Chinese Medicine Hospital, Wen Zhou, Zhe Jiang province People's Republic of China
| | - Qian Wang
- Tianjia Genomes Tech CO., LTD., No. 6 Longquan Road, Anhui Chaohu economic develop zone, Hefei, 238014 People's Republic of China
| | - Jizhou Zhang
- Department of Medical Oncology, Zhe Jiang Chinese Medicine University affiliated Chinese Medicine Hospital, Wen Zhou, Zhe Jiang province People's Republic of China
| | - Bin Zhou
- Department of Medical Oncology, Zhe Jiang Chinese Medicine University affiliated Chinese Medicine Hospital, Wen Zhou, Zhe Jiang province People's Republic of China
| | - Jiaohong Wu
- 3Department of Gynecology and Oncology, Wen Zhou Medical University affiliated People's Hospital, Wen Zhou, Zhe Jiang province People's Republic of China
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18
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Wei Y, Sun Z, Wang Y, Xie Z, Xu S, Xu Y, Zhou X, Bi J, Zhu Z. Methylation in the TP53 promoter is associated with ischemic stroke. Mol Med Rep 2019; 20:1404-1410. [PMID: 31173230 DOI: 10.3892/mmr.2019.10348] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 03/06/2019] [Indexed: 11/05/2022] Open
Abstract
Cerebral ischemic stroke (IS) is a disease presenting high morbidity and mortality rates worldwide. Understanding of the pathogenesis underlying IS may facilitate the development of effective clinical therapeutic strategies and improve the prevention of this disease, decreasing its occurrence rate. Epigenetic alterations have recently attracted attention as possible mechanisms underlying IS. Additionally, tumor protein p53 (TP53) was identified to be involved in the pathophysiology of cerebral stroke. In the present study, the methylation status of the TP53 promoter was investigated in patients with IS and in age‑matched healthy controls. The methylation status of the promoter of TP53 was significantly increased in patients with IS compared with healthy subjects. Additionally, the methylation level of the TP53 promoter was identified to be associated with carotid intima‑media thickness, the degree of carotid atherosclerosis and the circulating levels of homocysteine in peripheral blood. The present findings may improve the understanding of the role of the epigenetic modifications of the TP53 promoter in IS pathogenesis.
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Affiliation(s)
- Yan Wei
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Zhongzheng Sun
- Department of Neurosurgery, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Yun Wang
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Zhaohong Xie
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Shunliang Xu
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Yingying Xu
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Xiaoyan Zhou
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Jianzhong Bi
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
| | - Zhengyu Zhu
- Department of Neurology Medicine, Second Hospital of Shandong University, Jinan, Shandong 250033, P.R. China
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Voropaeva EN, Pospelova TI, Voevoda MI, Maksimov VN, Orlov YL, Seregina OB. Clinical aspects of TP53 gene inactivation in diffuse large B-cell lymphoma. BMC Med Genomics 2019; 12:35. [PMID: 30871527 DOI: 10.1186/s12920-019-0484-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Background The knowledge about specific mechanisms generating TP53 dysfunction in diffuse large B-cell lymphoma is limited. The aim of the current study was to comprehensively explore TP53 gene variability resulting from somatic mutations, promoter methylation, and allelic imbalance in tumorous tissue of diffuse large B-cell lymphoma (DLBCL). Methods DNA samples from 74 patients with DLBCL were used. Genomic DNA was isolated from paraffin blocks of lymph nodes or from extranodal biopsies of tumors by the phenol–chloroform extraction method with guanidine. Analysis of coding sequences of the TP53 gene was based on Sanger’s direct sequencing method. The methylation status of the TP53 promoter was analyzed using by methylation-specific PCR on bisulfite-converted DNA. Assessment of the detected mutations was carried out in the IARC TP53 Database and the TP53 UMD mutation database of human cancer. Results The mutations in regions coding for the DNA-binding domain were prevalent (95%). In the analyzed sample of patients, codons 275, 155, 272, and 212 were hotspots of mutations in the TP53 gene. In addition, functionally significant intron mutations (IVS6-36G > C and IVS5 + 43G > T) were detected. Instances of TP53 promoter methylation were observed only in a few samples of diffuse large B-cell lymphoma tissue. Furthermore, loss of heterozygosity was revealed only in the subgroup of patients with altered status of the gene (mutations were detected in five patients and promoter methylation in one case). Conclusions Thus, the results suggest that there are two sequential events in the formation of diffuse large B-cell lymphoma in at least some cases. The first event is mutation or methylation of the TP53 promoter, leading to appearance of a cell with increased risk of malignant transformation. The second event is the loss of an intact allele of the gene; this change is necessary for tumorigenesis. We identified TP53 mutation patterns in a Russian cohort of patients with de novo DLBCL who were treated with R-CHOP and R-CHOP-like regimens and confirmed that TP53 mutation status is a valuable prognostic biomarker.
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Mansourian M, Mahnam K, Rajabi HR, Roushani M, Doustimotlagh AH. Exploring the binding mechanism of saccharin and sodium saccharin to promoter of human p53 gene by theoretical and experimental methods. J Biomol Struct Dyn 2019; 38:548-564. [PMID: 30856053 DOI: 10.1080/07391102.2019.1582438] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the past few decades, extensive discussions have been on the impact of artificial sweeteners on the risk of cancer. The present study aimed to evaluate the interaction of saccharin (SA) and sodium saccharin (SSA) with the promoter of the human p53 gene. The binding ability was assessed using the spectroscopic technique, molecular docking and molecular dynamics (MD) simulation methods. Free energy of binding has been calculated using Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) method. Fluorescence spectra of mentioned gene with concentration profiles of SA and SSA were obtained in a physiological condition. A gradual increase without any significant spectral shift in the fluorescence intensity of around 350 nm was evident, indicating the presence of an interaction between both compounds and gene. The docking results showed that both compounds were susceptible to bind to 5'-DG56DG57-3' nucleotide sequence of gene. Furthermore, the MD simulation demonstrated that the binding positions for SA and SSA were 5'-A1T3T4-3' and 5'-G44T45-3' sequences of gene, respectively. The binding of these sweeteners to gene made significant conformational changes to the DNA structure. Hydrogen and hydrophobic interactions are the major forces in complexes stability. Through the groove binding mode, the non-interactive DNA-binding nature of SSA and SA has been demonstrated by the results of spectrofluorometric and molecular modeling. This study could provide valuable insight into the binding mechanism of SA and its salt with p53 gene promoter as macromolecule at the molecular level in atomistic details. This work can contribute to the possibility of the potential hazard of carcinogenicity of this sweetener and to design and apply new and safer artificial sweeteners. AbbreviationsSASaccharinSSASodium SaccharinPp53gpromoter of human p53 geneMDMolecular dynamicsRMSDRoot-mean-square deviationRMSFRoot-mean-square fluctuationRgRadius of GyrationSASASolvent-Accessible Surface AreaADIAcceptable daily intakeMM/PBSAMolecular Mechanics/Poisson-Boltzmann Surface AreaCommunicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Mahboubeh Mansourian
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.,Department of Pharmacology, Faculty of Medicine, Yasuj University of Medical Sciences, Yasuj, I.R. Iran
| | - Karim Mahnam
- Faculty of Science, Department of Biology, Shahrekord University, Shahrekord, Iran.,Nanotechnology Research Center, Shahrekord University, Shahrekord, Iran
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Yu Y, Qi J, Xiong J, Jiang L, Cui D, He J, Chen P, Li L, Wu C, Ma T, Shao S, Wang J, Yu D, Zhou B, Huang D, Schmitt CA, Tao R. Epigenetic Co-Deregulation of EZH2/TET1 is a Senescence-Countering, Actionable Vulnerability in Triple-Negative Breast Cancer. Am J Cancer Res 2019; 9:761-777. [PMID: 30809307 PMCID: PMC6376470 DOI: 10.7150/thno.29520] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 12/22/2018] [Indexed: 12/13/2022] Open
Abstract
Triple-negative breast cancer (TNBC) cells lack the expression of ER, PR and HER2. Thus, TNBC patients cannot benefit from hormone receptor-targeted therapy as non-TNBC patients, but can only receive chemotherapy as the systemic treatment and have a worse overall outcome. More effective therapeutic targets and combination therapy strategies are urgently needed to improve the treatment effectiveness. Methods: We analyzed the expression levels of EZH2 and TET1 in TCGA and our own breast cancer patient cohort, and tested their correlation with patient survival. We used TNBC and non-TNBC cell lines and mouse xenograft tumor model to unveil novel EZH2 targets and investigated the effect of EZH2 inhibition or TET1 overexpression in cell proliferation and viability of TNBC cells. Results: In TNBC cells, EZH2 decreases TET1 expression by H3K27me3 epigenetic regulation and subsequently suppresses anti-tumor p53 signaling pathway. Patients with high EZH2 and low TET1 presented the poorest survival outcome. Experimentally, targeting EZH2 in TNBC cells with specific inhibitor GSK343 or shRNA genetic approach could induce cell cycle arrest and senescence by elevating TET1 expression and p53 pathway activation. Using mouse xenograft model, we have tested a novel therapy strategy to combine GSK343 and chemotherapy drug Adriamycin and could show drastic and robust inhibition of TNBC tumor growth by synergistic induction of senescence and apoptosis. Conclusions: We postulate that the well-controlled dynamic pathway EZH2-H3K27me3-TET1 is a novel epigenetic co-regulator module and provide evidence regarding how to exploit it as a novel therapeutic target via its pivotal role in senescence and apoptosis control. Of clinical and therapeutic significance, the present study opens a new avenue for TNBC treatment by targeting the EZH2-H3K27me3-TET1 pathway that can modulate the epigenetic landscape.
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22
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Jeong G, Bae H, Jeong D, Ham J, Park S, Kim HW, Kang HS, Kim SJ. A Kelch domain-containing KLHDC7B and a long non-coding RNA ST8SIA6-AS1 act oppositely on breast cancer cell proliferation via the interferon signaling pathway. Sci Rep 2018; 8:12922. [PMID: 30150751 PMCID: PMC6110865 DOI: 10.1038/s41598-018-31306-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 08/16/2018] [Indexed: 12/17/2022] Open
Abstract
In our previous study, the Kelch domain-containing 7B (KLHDC7B) was revealed to be hypermethylated at the promoter but upregulated in breast cancer. In this study, we identified a long non-coding RNA, ST8SIA6-AS1 (STAR1), whose expression was significantly associated with KLHDC7B in breast cancer (R2 = 0.3466, P < 0.01). Involvement of the two genes in tumorigenesis was examined via monitoring their effect on cellular as well as molecular events after each gene dysregulation in cultured mammary cell lines. Apoptosis of MCF-7 decreased by 49.5% and increased by 33.1%, while proliferation noted increase and decrease by up- and downregulation of KLHDC7B, respectively, suggesting its oncogenic property. STAR1, however, suppressed cell migration and increased apoptosis. Network analysis identified many target genes that appeared to have similar regulation, especially in relation to the interferon signaling pathway. Concordantly, expression of genes such as IFITs, STATs, and IL-29 in that pathway was affected by KLHDC7B and STAR1. Taken together, KLHDC7B and STAR1 are both overexpressed in breast cancer and significantly associated with gene modulation activity in the interferon signaling pathway during breast tumorigenesis.
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Affiliation(s)
- Gookjoo Jeong
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea
- PanGen Biotech Inc, Suwon, 16675, Republic of Korea
| | - Hansol Bae
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea
| | - Dawoon Jeong
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea
| | - Juyeon Ham
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea
| | - Sungbin Park
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea
| | - Hyeon Woo Kim
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea
| | - Han-Sung Kang
- Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea
| | - Sun Jung Kim
- Department of Life Science, Dongguk University-Seoul, Goyang, Republic of Korea.
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23
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Moghadam BT, Zamani N, Komorowski J, Grabherr M. PiiL: visualization of DNA methylation and gene expression data in gene pathways. BMC Genomics 2017; 18:571. [PMID: 28768481 PMCID: PMC5541427 DOI: 10.1186/s12864-017-3950-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 07/18/2017] [Indexed: 11/21/2022] Open
Abstract
Background DNA methylation is a major mechanism involved in the epigenetic state of a cell. It has been observed that the methylation status of certain CpG sites close to or within a gene can directly affect its expression, either by silencing or, in some cases, up-regulating transcription. However, a vertebrate genome contains millions of CpG sites, all of which are potential targets for methylation, and the specific effects of most sites have not been characterized to date. To study the complex interplay between methylation status, cellular programs, and the resulting phenotypes, we present PiiL, an interactive gene expression pathway browser, facilitating analyses through an integrated view of methylation and expression on multiple levels. Results PiiL allows for specific hypothesis testing by quickly assessing pathways or gene networks, where the data is projected onto pathways that can be downloaded directly from the online KEGG database. PiiL provides a comprehensive set of analysis features that allow for quick and specific pattern searches. Individual CpG sites and their impact on host gene expression, as well as the impact on other genes present in the regulatory network, can be examined. To exemplify the power of this approach, we analyzed two types of brain tumors, Glioblastoma multiform and lower grade gliomas. Conclusion At a glance, we could confirm earlier findings that the predominant methylation and expression patterns separate perfectly by mutations in the IDH genes, rather than by histology. We could also infer the IDH mutation status for samples for which the genotype was not known. By applying different filtering methods, we show that a subset of CpG sites exhibits consistent methylation patterns, and that the status of sites affect the expression of key regulator genes, as well as other genes located downstream in the same pathways. PiiL is implemented in Java with focus on a user-friendly graphical interface. The source code is available under the GPL license from https://github.com/behroozt/PiiL.git. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3950-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Behrooz Torabi Moghadam
- Department of Cell and Molecular Biology, Computational and Systems Biology, Uppsala University, Uppsala, Sweden
| | - Neda Zamani
- Department of Medical Biochemistry and Microbiology/BILS, Genomics, Uppsala University, Uppsala, Sweden.,Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Jan Komorowski
- Department of Cell and Molecular Biology, Computational and Systems Biology, Uppsala University, Uppsala, Sweden.,Institute of Computer Science, Polish Academy of Sciences, 01248, Warsaw, Poland
| | - Manfred Grabherr
- Department of Medical Biochemistry and Microbiology/BILS, Genomics, Uppsala University, Uppsala, Sweden.
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Seawright JW, Samman Y, Sridharan V, Mao XW, Cao M, Singh P, Melnyk S, Koturbash I, Nelson GA, Hauer-Jensen M, Boerma M. Effects of low-dose rate γ-irradiation combined with simulated microgravity on markers of oxidative stress, DNA methylation potential, and remodeling in the mouse heart. PLoS One 2017; 12:e0180594. [PMID: 28678877 PMCID: PMC5498037 DOI: 10.1371/journal.pone.0180594] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 06/16/2017] [Indexed: 01/31/2023] Open
Abstract
Purpose Space travel is associated with an exposure to low-dose rate ionizing radiation and the microgravity environment, both of which may lead to impairments in cardiac function. We used a mouse model to determine short- and long-term cardiac effects to simulated microgravity (hindlimb unloading; HU), continuous low-dose rate γ-irradiation, or a combination of HU and low-dose rate γ-irradiation. Methods Cardiac tissue was obtained from female, C57BL/6J mice 7 days, 1 month, 4 months, and 9 months following the completion of a 21 day exposure to HU or a 21 day exposure to low-dose rate γ-irradiation (average dose rate of 0.01 cGy/h to a total of 0.04 Gy), or a 21 day simultaneous exposure to HU and low-dose rate γ-irradiation. Immunoblot analysis, rt-PCR, high-performance liquid chromatography, and histology were used to assess inflammatory cell infiltration, cardiac remodeling, oxidative stress, and the methylation potential of cardiac tissue in 3 to 6 animals per group. Results The combination of HU and γ-irradiation demonstrated the strongest increase in reduced to oxidized glutathione ratios 7 days and 1 month after treatment, but a difference was no longer apparent after 9 months. On the other hand, no significant changes in 4-hydroxynonenal adducts was seen in any of the groups, at the measured endpoints. While manganese superoxide dismutase protein levels decreased 9 months after low-dose γ-radiation, no changes were observed in expression of catalase or Nrf2, a transcription factor that determines the expression of several antioxidant enzymes, at the measured endpoints. Inflammatory marker, CD-2 protein content was significantly decreased in all groups 4 months after treatment. No significant differences were observed in α-smooth muscle cell actin protein content, collagen type III protein content or % total collagen. Conclusions This study has provided the first and relatively broad analysis of small molecule and protein markers of oxidative stress, T-lymphocyte infiltration, and cardiac remodeling in response to HU with simultaneous exposure to low-dose rate γ-radiation. Results from the late observation time points suggest that the hearts had mostly recovered from these two experimental conditions. However, further research is needed with larger numbers of animals for a more robust statistical power to fully characterize the early and late effects of simulated microgravity combined with exposure to low-dose rate ionizing radiation on the heart.
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Affiliation(s)
- John W. Seawright
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
- * E-mail:
| | - Yusra Samman
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Vijayalakshmi Sridharan
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Xiao Wen Mao
- Department of Basic Sciences and Radiation Medicine, Loma Linda University, Loma Linda, CA, The United States of America
| | - Maohua Cao
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Preeti Singh
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Stepan Melnyk
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Igor Koturbash
- Department of Environmental and Occupational Health, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Gregory A. Nelson
- Department of Basic Sciences and Radiation Medicine, Loma Linda University, Loma Linda, CA, The United States of America
| | - Martin Hauer-Jensen
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
| | - Marjan Boerma
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, The United States of America
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Cardoso MDFS, Castelletti CHM, Lima-Filho JLD, Martins DBG, Teixeira JAC. Putative biomarkers for cervical cancer: SNVs, methylation and expression profiles. Mutat Res Rev Mutat Res 2017; 773:161-173. [PMID: 28927526 DOI: 10.1016/j.mrrev.2017.06.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 02/08/2023]
Abstract
Cervical cancer is primarily caused by Human papillomavirus (HPV) infection, but other factors such as smoking habits, co-infections and genetic background, can also contribute to its development. Although this cancer is avoidable, it is the fourth most frequent type of cancer in females worldwide and can only be treated with chemotherapy and radical surgery. There is a need for biomarkers that will enable early diagnosis and targeted therapy for this type of cancer. Therefore, a systems biology pipeline was applied in order to identify potential biomarkers for cervical cancer, which show significant reports in three molecular aspects: DNA sequence variants, DNA methylation pattern and alterations in mRNA/protein expression levels. CDH1, CDKN2A, RB1 and TP53 genes were selected as putative biomarkers, being involved in metastasis, cell cycle regulation and tumour suppression. Other ten genes (CDH13, FHIT, PTEN, MLH1, TP73, CDKN1A, CACNA2D2, TERT, WIF1, APC) seemed to play a role in cervical cancer, but the lack of studies prevented their inclusion as possible biomarkers. Our results highlight the importance of these genes. However, further studies should be performed to elucidate the impact of DNA sequence variants and/or epigenetic deregulation and altered expression of these genes in cervical carcinogenesis and their potential as biomarkers for cervical cancer diagnosis and prognosis.
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Affiliation(s)
- Maria de Fátima Senra Cardoso
- Molecular Prospection and Bioinformatics Group (ProspecMol), Laboratory of Immunopathology Keizo Asami (LIKA), Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil.
| | - Carlos Henrique Madeiros Castelletti
- Molecular Prospection and Bioinformatics Group (ProspecMol), Laboratory of Immunopathology Keizo Asami (LIKA), Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil; Agronomic Institute of Pernambuco (IPA), Av. General San Martin 1371, Bongi, Recife - PE, 50761-000, Brazil
| | - José Luiz de Lima-Filho
- Laboratory of Immunopathology Keizo Asami (LIKA), Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil; Biochemistry Department, Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil
| | - Danyelly Bruneska Gondim Martins
- Molecular Prospection and Bioinformatics Group (ProspecMol), Laboratory of Immunopathology Keizo Asami (LIKA), Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil; Biochemistry Department, Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil
| | - José António Couto Teixeira
- Laboratory of Immunopathology Keizo Asami (LIKA), Federal University of Pernambuco (UFPE), Av. Prof. Moraes Rego s/n, Recife - PE, 50670-901, Brazil; Department of Biological Engineering, University of Minho (UM), Campus de Gualtar, 4710-057 Braga, Portugal
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Lourenço AR, Coffer PJ. A tumor suppressor role for C/EBPα in solid tumors: more than fat and blood. Oncogene 2017; 36:5221-30. [PMID: 28504718 DOI: 10.1038/onc.2017.151] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 03/29/2017] [Accepted: 04/10/2017] [Indexed: 12/12/2022]
Abstract
The transcription factor CCAAT/enhancer-binding protein alpha (C/EBPα) plays a critical role during embryogenesis and is thereafter required for homeostatic glucose metabolism, adipogenesis and myeloid development. Its ability to regulate the expression of lineage-specific genes and induce growth arrest contributes to the terminal differentiation of several cell types, including hepatocytes, adipocytes and granulocytes. CEBPA loss of-function mutations contribute to the development of ~10% of acute myeloid leukemia (AML), stablishing a tumor suppressor role for C/EBPα. Deregulation of C/EBPα expression has also been reported in a variety of additional human neoplasias, including liver, breast and lung cancer. However, functional CEBPA mutations have not been found in solid tumors, suggesting that abrogation of C/EBPα function in non-hematopoietic tissues is regulated by alternative mechanisms. Here we review the function of C/EBPα in solid tumors and focus on the molecular mechanisms underlying its tumor suppressive role.
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Herrero AB, Rojas EA, Misiewicz-Krzeminska I, Krzeminski P, Gutiérrez NC. Molecular Mechanisms of p53 Deregulation in Cancer: An Overview in Multiple Myeloma. Int J Mol Sci 2016; 17:E2003. [PMID: 27916892 DOI: 10.3390/ijms17122003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 11/14/2016] [Accepted: 11/22/2016] [Indexed: 12/12/2022] Open
Abstract
The p53 pathway is inactivated in the majority of human cancers. Although this perturbation frequently occurs through the mutation or deletion of p53 itself, there are other mechanisms that can attenuate the pathway and contribute to tumorigenesis. For example, overexpression of important p53 negative regulators, such as murine double minute 2 (MDM2) or murine double minute 4 (MDM4), epigenetic deregulation, or even alterations in TP53 mRNA splicing. In this work, we will review the different mechanisms of p53 pathway inhibition in cancer with special focus on multiple myeloma (MM), the second most common hematological malignancy, with low incidence of p53 mutations/deletions but growing evidence of indirect p53 pathway deregulation. Translational implications for MM and cancer prognosis and treatment are also reviewed.
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Abstract
Alternative splicing (AS) of mRNA precursors is a ubiquitous mechanism for generating numerous transcripts with different activities from one genomic locus in mammalian cells. The gene products from a single locus can thus have similar, dominant-negative or even opposing functions. Aberrant AS has been found in cancer to express proteins that promote cell growth, local invasion and metastasis. This review will focus on the aberrant splicing of tumor suppressor/oncogenes that belong to the DMP1-ARF-MDM2-p53 pathway. Our recent study shows that the DMP1 locus generates both tumor-suppressive DMP1α (p53-dependent) and oncogenic DMP1β (p53-independent) splice variants, and the DMP1β/α ratio increases with neoplastic transformation of breast epithelial cells. This process is associated with high DMP1β protein expression and shorter survival of breast cancer (BC) patients. Accumulating pieces of evidence show that ARF is frequently inactivated by aberrant splicing in human cancers, demonstrating its involvement in human malignancies. Splice variants from the MDM2 locus promote cell growth in culture and accelerate tumorigenesis in vivo. Human cancers expressing these splice variants are associated with advanced stage/metastasis, and thus have negative clinical impacts. Although they lack most of the p53-binding domain, their activities are mostly dependent on p53 since they bind to wild-type MDM2. The p53 locus produces splice isoforms that have either favorable (β/γ at the C-terminus) or negative impact (Δ40, Δ133 at the N-terminus) on patients' survival. As the oncogenic AS products from these loci are expressed only in cancer cells, they may eventually become targets for molecular therapies.
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Affiliation(s)
- Kazushi Inoue
- The Department of Pathology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157 USA
| | - Elizabeth A. Fry
- The Department of Pathology, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157 USA
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Kamiya T, Goto A, Kurokawa E, Hara H, Adachi T. Cross Talk Mechanism among EMT, ROS, and Histone Acetylation in Phorbol Ester-Treated Human Breast Cancer MCF-7 Cells. Oxid Med Cell Longev 2016; 2016:1284372. [PMID: 27127545 DOI: 10.1155/2016/1284372] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/17/2016] [Accepted: 03/20/2016] [Indexed: 01/12/2023]
Abstract
Epithelial-mesenchymal transition (EMT) plays a pivotal role in the progression of cancer, and some transcription factors including Slug and Snail are known to be involved in EMT processes. It has been well established that the excess production of reactive oxygen species (ROS) and epigenetics such as DNA methylation and histone modifications participate in carcinogenesis; however, the cross talk mechanism among EMT, ROS, and epigenetics remains unclear. In the present study, we demonstrated that the treatment of human breast cancer MCF-7 cells with phorbol ester (TPA), a protein kinase C activator, significantly induced cell proliferation and migration, and these were accompanied by the significant induction of Slug expression. Moreover, the TPA-elicited induction of Slug expression was regulated by histone H3 acetylation and NADPH oxidase (NOX) 2-derived ROS signaling, indicating that ROS and histone acetylation are involved in TPA-elicited EMT processes. We herein determined the cross talk mechanism among EMT, ROS, and histone acetylation, and our results provide an insight into the progression of cancer metastasis.
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Hattori S, Kamiya T, Hara H, Ninomiya M, Koketsu M, Adachi T. CoCl 2 Decreases EC-SOD Expression through Histone Deacetylation in COS7 Cells. Biol Pharm Bull 2016; 39:2036-2041. [DOI: 10.1248/bpb.b16-00551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Shuhei Hattori
- Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University
| | - Tetsuro Kamiya
- Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University
| | - Hirokazu Hara
- Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University
| | - Masayuki Ninomiya
- Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University
| | - Mamoru Koketsu
- Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University
| | - Tetsuo Adachi
- Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University
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Phan NLC, Trinh NV, Pham PV. Low concentrations of 5-aza-2'-deoxycytidine induce breast cancer stem cell differentiation by triggering tumor suppressor gene expression. Onco Targets Ther 2015; 9:49-59. [PMID: 26730203 PMCID: PMC4694670 DOI: 10.2147/ott.s96291] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background Breast cancer stem cells (BCSCs) are considered the cause of tumor growth, multidrug resistance, metastasis, and recurrence. Therefore, differentiation therapy to reduce self-renewal of BCSCs is a promising approach. We have examined the effects of 5-aza-2′-deoxycytidine (DAC) on BCSC differentiation. Materials and methods BCSCs were treated with a range of DAC concentrations from 0.625 to 100 µM. The differentiation status of DAC-treated BCSCs was graded by changes in cell proliferation, CD44+CD24− phenotype, expression of tumor suppressor genes, including BRCA1, BRCA2, p15, p16, p53, and PTEN, and antitumor drug resistance. Results DAC treatment caused significant BCSC differentiation. BCSCs showed a 15%–23% reduction in proliferation capacity, 3.0%–21.3% decrease in the expression of BCSC marker CD44+/CD24−, activation of p53 expression, and increased p15, p16, BRCA1, and BRCA2 expression. Concentrations of DAC ranging from 0.625 to 40 µM efficiently induce cell cycle arrest in S-phase. ABCG2, highly expressed in BCSCs, also decreased with DAC exposure. Of particular note, drug-sensitivity of BCSCs to doxorubicin, verapamil, and tamoxifen also increased 1.5-, 2.0-, and 3.7-fold, respectively, after pretreatment with DAC. Conclusion DAC reduced breast cancer cell survival and induced differentiation through reexpression of tumor suppressor genes. These results indicate the potential of DAC in targeting specific chemotherapy-resistant cells within a tumor.
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Affiliation(s)
- Nhan Lu-Chinh Phan
- Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh City, Vietnam
| | - Ngu Van Trinh
- Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh City, Vietnam
| | - Phuc Van Pham
- Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh City, Vietnam
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Chen L, Zhang GX, Zhou Y, Zhang CX, Xie YY, Xiang C, He XY, Zhang Q, Liu G. BAC transgenic mice provide evidence that p53 expression is highly regulated in vivo. Cell Death Dis 2015; 6:e1878. [PMID: 26379189 DOI: 10.1038/cddis.2015.224] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 05/11/2015] [Accepted: 05/20/2015] [Indexed: 12/17/2022]
Abstract
p53 is an important tumor suppressor and stress response mediator. Proper control of p53 level and activity is tightly associated with its function. Posttranslational modifications and the interactions with Mdm2 and Mdm4 are major mechanisms controlling p53 activity and stability. As p53 protein is short-lived and hardly detectable in unstressed situations, less is known on its basal level expression and the corresponding controlling mechanisms in vivo. In addition, it also remains obscure how p53 expression might contribute to its functional regulation. In this study, we established bacterial artificial chromosome transgenic E.coli β-galactosidase Z gene reporter mice to monitor p53 expression in mouse tissues and identify important regulatory elements critical for the expression in vivo. We revealed preferentially high level of p53 reporter expressions in the proliferating, but not the differentiated compartments of the majority of tissues during development and tissue homeostasis. In addition, tumors as well as regenerating tissues in the p53 reporter mice also expressed high level of β-gal. Furthermore, both the enhancer box sequence (CANNTG) in the p53 promoter and the 3′ terminal untranslated region element were critical in mediating the high-level expression of the reporter. We also provided evidence that cellular myelocytomatosis oncogene was a critical player regulating p53 mRNA expression in proliferating cells and tissues. Finally, we found robust p53 activation preferentially in the proliferating compartment of mouse tissues upon DNA damage and the proliferating cells exhibited an enhanced p53 response as compared with cells in a quiescent state. Together, these results suggested a highly regulated expression pattern of p53 in the proliferating compartment controlled by both transcriptional and posttranscriptional mechanisms, and such regulated p53 expression may impose functional significance upon stress by setting up a precautionary mode in defense of cellular transformation and tumorigenesis.
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Mohiuddin MK, Chava S, Upendrum P, Latha M, Zubeda S, Kumar A, Ahuja YR, Hasan Q, Mohan V. Role of Human papilloma virus infection and altered methylation of specific genes in esophageal cancer. Asian Pac J Cancer Prev 2014; 14:4187-93. [PMID: 23991974 DOI: 10.7314/apjcp.2013.14.7.4187] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Evaluation of Human papilloma virus (HPV) and its association with promoter methylation of candidate genes, p53 and Aurora A in esophageal cancer. MATERIALS AND METHODS One hundred forty-one esophageal tissue samples from different pathologies were evaluated for HPV infection by PCR, while the promoter methylation status of p53 and Aurora A was assessed by methylation-specific restriction based PCR assay. Statistical analyses were performed with MedCalc and MDR software. RESULTS Based on endoscopy and histopathology, samples were categorized: cancers (n=56), precancers (n=7), esophagitis (n=19) and normals (n=59). HPV infection was found to be less common in cancers (19.6%), whereas its prevalence was relatively high in precancers (71.4%), esophagitis (57.8%) and normals (45.7%). p53 promoter methylation did not show any significant difference between cancer and normal tissues, whereas Aurora A promoter methylation demonstrated significant association with disease (p=0.00016, OR:5.6452, 95%CI:2.18 to 14.6) when compared to normals. Aurora A methylation and HPV infection was found in a higher percentages of precancer (66.6%), esophagitis (54.5%) and normal (45.2%) when compared to cancers (14.2%). CONCLUSIONS Aurora A promoter methylation is significantly associated with esophageal cancer, but the effect of HPV infection on this epigenetic alteration is not significant. However MDR analysis showed that the hypostatic effect of HPV was nullified when the cases had Aurora methylation and tobacco exposure. Further HPV sub-typing may give an insight into its reduced prevalence in esophageal cancer verses normal tissue. However, with the present data it is difficult to assign any significant role to HPV in the etiopathology of esophageal cancer.
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Affiliation(s)
- Mohammed Khaliq Mohiuddin
- Department of Genetics, Vasavi Medical and Research Centre, Kamineni Hospitals, LB Nagar, Andhra Pradesh, India.
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Di Fiore R, Marcatti M, Drago-Ferrante R, D'Anneo A, Giuliano M, Carlisi D, De Blasio A, Querques F, Pastore L, Tesoriere G, Vento R. Mutant p53 gain of function can be at the root of dedifferentiation of human osteosarcoma MG63 cells into 3AB-OS cancer stem cells. Bone 2014; 60:198-212. [PMID: 24373920 DOI: 10.1016/j.bone.2013.12.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 11/25/2013] [Accepted: 12/17/2013] [Indexed: 12/13/2022]
Abstract
Osteosarcoma is a highly metastatic tumor affecting adolescents, for which there is no second-line chemotherapy. As suggested for most tumors, its capability to overgrow is probably driven by cancer stem cells (CSCs), and finding new targets to kill CSCs may be critical for improving patient survival. TP53 is the most frequently mutated tumor suppressor gene in cancers and mutant p53 protein (mutp53) can acquire gain of function (GOF) strongly contributing to malignancy. Studies thus far have not shown p53-GOF in osteosarcoma. Here, we investigated TP53 gene status/role in 3AB-OS cells-a highly aggressive CSC line previously selected from human osteosarcoma MG63 cells-to evaluate its involvement in promoting proliferation, invasiveness, resistance to apoptosis and stemness. By RT-PCR, methylation-specific PCR, fluorescent in situ hybridization, DNA sequence, western blot and immunofluorescence analyses, we have shown that-in comparison with parental MG63 cells where TP53 gene is hypermethylated, rearranged and in single copy-in 3AB-OS cells, TP53 is unmethylated, rearranged and in multiple copies, and mutp53 (p53-R248W/P72R) is post-translationally modified and with nuclear localization. p53-R248W/P72R-knockdown by short-interfering RNA reduced the growth and replication rate of 3AB-OS cells, markedly increasing cell cycle inhibitor levels and sensitized 3AB-OS cells to TRAIL-induced apoptosis by DR5 up-regulation; moreover, it strongly decreased the levels of stemness and invasiveness genes. We have also found that the ectopic expression of p53-R248W/P72R in MG63 cells promoted cancer stem-like features, as high proliferation rate, sphere formation, clonogenic growth, high migration and invasive ability; furthermore, it strongly increased the levels of stemness proteins. Overall, the findings suggest the involvement of p53-R248W/P72R at the origin of the aberrant characters of the 3AB-OS cells with the hypothesis that its GOF can be at the root of the dedifferentiation of MG63 cells into CSCs.
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Affiliation(s)
- Riccardo Di Fiore
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy
| | - Michela Marcatti
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy
| | - Rosa Drago-Ferrante
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy
| | - Antonella D'Anneo
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy
| | - Michela Giuliano
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy
| | - Daniela Carlisi
- Laboratory of Biochemistry, Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Polyclinic, Palermo, Italy
| | - Anna De Blasio
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy
| | - Francesca Querques
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II," Naples, Italy; CEINGE-Advanced Biotechnology s.c.a.r.l., Naples, Italy
| | - Lucio Pastore
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II," Naples, Italy; CEINGE-Advanced Biotechnology s.c.a.r.l., Naples, Italy
| | - Giovanni Tesoriere
- Institute for Cancer Research and Molecular Medicine and Center of Biotechnology, College of Science and Biotechnology, Temple University, Philadelphia, PA, USA
| | - Renza Vento
- Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy; Institute for Cancer Research and Molecular Medicine and Center of Biotechnology, College of Science and Biotechnology, Temple University, Philadelphia, PA, USA.
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Aloni-Grinstein R, Shetzer Y, Kaufman T, Rotter V. p53: the barrier to cancer stem cell formation. FEBS Lett 2014; 588:2580-9. [PMID: 24560790 DOI: 10.1016/j.febslet.2014.02.011] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 02/07/2014] [Accepted: 02/07/2014] [Indexed: 02/08/2023]
Abstract
The role of p53 as the "guardian of the genome" in differentiated somatic cells, triggering various biological processes, is well established. Recent studies in the stem cell field have highlighted a profound role of p53 in stem cell biology as well. These studies, combined with basic data obtained 20 years ago, provide insight into how p53 governs the quantity and quality of various stem cells, ensuring a sufficient repertoire of normal stem cells to enable proper development, tissue regeneration and a cancer free life. In this review we address the role of p53 in genomically stable embryonic stem cells, a unique predisposed cancer stem cell model and adult stem cells, its role in the generation of induced pluripotent stem cells, as well as its role as the barrier to cancer stem cell formation.
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Affiliation(s)
- Ronit Aloni-Grinstein
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yoav Shetzer
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tom Kaufman
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Varda Rotter
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
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Jesionek-Kupnicka D, Szybka M, Malachowska B, Fendler W, Potemski P, Piaskowski S, Jaskolski D, Papierz W, Skowronski W, Och W, Kordek R, Zawlik I. TP53 promoter methylation in primary glioblastoma: relationship with TP53 mRNA and protein expression and mutation status. DNA Cell Biol 2014; 33:217-26. [PMID: 24506545 DOI: 10.1089/dna.2013.2201] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Reduced expression of TP53 by promoter methylation has been reported in several neoplasms. It remains unclear whether TP53 promoter methylation is associated with reduced transcriptional and protein expression in glioblastoma (GB). The aim of our work was to study the impact of TP53 methylation and mutations on TP53 mRNA level and protein expression in 42 molecularly characterized primary GB tumors. We also evaluate the impact of all molecular alterations on the overall patient survival. The frequency of TP53 promoter methylation was found in 21.4%. To the best of our knowledge, this is the first report showing such high frequency of TP53 promoter methylation in primary GB. There was no relation between TP53 promoter methylation and TP53 mRNA level (p=0.5722) and between TP53 promoter methylation and TP53 protein expression (p=0.2045). No significant associations were found between TP53 mRNA expression and mutation of TP53 gene (p=0.9076). However, significant association between TP53 mutation and TP53 protein expression was found (p=0.0016). Our data suggest that in primary GB TP53 promoter methylation does not play a role in silencing of TP53 transcriptional and protein expression and is probably regulated by other genetic and epigenetic mechanisms associated with genes involved in the TP53 pathway.
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Kang S, Kim B, Park SB, Jeong G, Kang HS, Liu R, Kim SJ. Stage-specific methylome screen identifies that NEFL is downregulated by promoter hypermethylation in breast cancer. Int J Oncol 2013; 43:1659-65. [PMID: 24026393 DOI: 10.3892/ijo.2013.2094] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 08/26/2013] [Indexed: 11/06/2022] Open
Abstract
Aberrant hypermethylation of promoter regions in specific genes is a key event in the formation and progression of breast cancers, and an increasing number of marker genes have been identified. However, few genes which show methylation change in accordance with the progression of breast cancer have been identified. To identify genes which consistently undergo promoter methylation alterations as the tumor develops from a benign to a malignant form, genome-wide methylation databases of breast cancer cell lines from stage I to stage IV were analyzed. Heatmap and cluster analysis revealed that the genome-wide methylation changes showed a good accordance with tumor progression. Seven out of 14,495 genes were found to be consistently increased alongside the promoter methylation level through the normal cell line to the cancer stage IV cell lines. NEFL, one of the in silico hypermethylated genes in cancer, showed hypermethylation and lower expression in the cancer cell line MDA-MB-231, as well as in cancer tissues (methylation, p<0.05; expression, p<0.01). The expression was restored by inducing demethylation of the promoter in MDA-MB-231 cells. Our findings may lend credence to the possibility of using tumor stage-specific alterations in methylation patterns as biomarkers for estimating prognosis and assessing treatment options for breast cancer.
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Affiliation(s)
- Seongeun Kang
- Department of Life Science, Dongguk University-Seoul, Seoul 100-715, Republic of Korea
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Abstract
Ductal carcinoma in situ (DCIS) is a non-obligate precursor lesion of invasive carcinoma of the breast. Current prognostic markers based on histopathological examination are unable to accurately predict which DCIS cases will progress to invasive carcinoma or recur after surgical excision. Epigenetic changes have been shown to be a significant driver of tumorigenesis, and DNA methylation of specific gene promoters provides predictive and prognostic markers in many types of cancer, including invasive breast cancer. In general, the spectrum of genes that are methylated in DCIS strongly resembles that seen in invasive ductal carcinoma. The identification of specific prognostic markers in DCIS remains elusive and awaits additional work investigating a large panel of methylatable genes by using sensitive and reproducible technologies. This review critically appraises the role of methylation in DCIS and its use as a biomarker.
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Payne KK, Manjili MH. Adaptive immune responses associated with breast cancer relapse. Arch Immunol Ther Exp (Warsz) 2012; 60:345-50. [PMID: 22911133 DOI: 10.1007/s00005-012-0185-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 05/28/2012] [Indexed: 12/21/2022]
Abstract
The generation, survival, and differentiation of breast cancer stem cells (BCSC) in immunocompetent hosts remain elusive. Some investigators have shown that BCSC can be induced from epithelial tumor cells by the pathologic epithelial to mesenchymal transition (EMT). Emerging evidence suggests that the induction of EMT among epithelial tumor cells originates from signals produced by the non-tumor cells that constitute the tumor microenvironment, including the immune effectors that infiltrate the tumors. Thus, this suggests that the immune system not only has anti-tumor function, but also paradoxically immunoedits tumors, facilitating tumor escape and progression. Indeed, many studies in human breast cancers show both positive and negative associations between the infiltration of various immune effectors (e.g., CD4 and CD8 T cells) and the propensity to relapse with metastatic disease. These observations suggest that distinct types of immune effector cells may induce or inhibit tumor relapse. This review focuses on recent advances in identifying components of the immune system that may directly induce tumor escape and relapse. We propose that levels of interferon (IFN)-γ production or levels of the expression of IFN-γ receptor α on tumor cells may determine whether tumor inhibitory or relapse-promoting effect of IFN-γ may prevail.
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Affiliation(s)
- Kyle K Payne
- Department of Microbiology and Immunology, Massey Cancer Center, Virginia Commonwealth University, 401 College Street, Box 980035, Richmond, VA 23298, USA
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Chmelarova M, Krepinska E, Spacek J, Laco J, Beranek M, Palicka V. Methylation in the p53 promoter in epithelial ovarian cancer. Clin Transl Oncol 2013; 15:160-3. [PMID: 22855178 DOI: 10.1007/s12094-012-0894-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 04/03/2012] [Indexed: 10/28/2022]
Abstract
OBJECTIVE Ovarian cancer is a leading cause of death from gynecologic tumors, however, the molecular and especially epigenetic events underlying this transformation are poorly understood. Promoter methylation status of tumor suppressor genes may be associated with transcriptional silencing and tumor progression. It has been shown that methylation of CpG dinucleotides located in the promoter region of p53 is associated with low expression levels of this gene. The aim of this study was to investigate promoter methylation of p53 gene in ovarian cancer by comparison with normal ovarian tissue. METHODS To search for promoter methylation of p53 gene we used methylation-specific PCR (MSP) to compare the methylation status of 66 tissue samples of ovarian cancer with 37 control samples. RESULTS In our study methylation specific PCR revealed p53 promoter methylation in 34 of 66 (51.5 %) of specimens with ovarian cancer. CONCLUSION These results indicate that methylation in p53 promoter region may play an important role in carcinogenesis of ovarian cancer and could potentially be used in screening of ovarian cancer, and may have implications for future chemotherapy based on epigenetic changes.
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Jha AK, Nikbakht M, Jain V, Sehgal A, Capalash N, Kaur J. Promoter hypermethylation of p73 and p53 genes in cervical cancer patients among north Indian population. Mol Biol Rep 2012; 39:9145-57. [PMID: 22729911 DOI: 10.1007/s11033-012-1787-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 06/09/2012] [Indexed: 12/31/2022]
Abstract
Hypermethylation of CpG islands leads to transcriptional silencing and it is the predominant mechanism of tumor suppressor gene inactivation in many tumors. Methylation-specific polymerase chain reaction was performed to analyse the methylation status of the promoter region of the tumor suppressor genes. Hypermethylation of the 5' CpG island of the p21 ( CIP1 ), p27 ( KIP1 ), p57 ( KIP2 ), p53, p73 and RB 1 gene promoter were found in 8.8, 8.8, 11.2, 12, 25.6 and 4.8 % of 125 cervical cancer samples from north Indian population, respectively. Methylation of p73 was significantly (P < 0.001) associated with the cervical cancer cases in comparison to controls. Significant correlation was also observed between the methylation of p73 gene and increase in the risk of cervical cancer among passive smokers. Promoter hypermethylation of p53 gene was also observed to be significant among oral contraceptive users and cervical cancer patients having age at first sexual intercourse <20 years whereas hypermethylation of other genes was not found to be significant in the present study. This is the first report showing significant hypermethylation of p73 and p53 genes among cervical cancer patients in north Indian population. This is also the first report on significant p53 hypermethylation in cervical cancer in any population. Our findings did not show any correlation between promoter methylation of p73 and the other genes under study with clinicopathological parameters, including human papillomavirus infection and stage of the disease. The frequency of aberrant methylation of p73 and p53 gene promoter was unchanged according to the age of patients.
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Amaral CLD, Bueno RDBEL, Burim RV, Queiroz RHC, Bianchi MDLP, Antunes LMG. The effects of dietary supplementation of methionine on genomic stability and p53 gene promoter methylation in rats. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2011; 722:78-83. [DOI: 10.1016/j.mrgentox.2011.03.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 03/15/2011] [Accepted: 03/17/2011] [Indexed: 01/13/2023]
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Ye W, Xu P, Jen R, Feng E, Zhong S, Li H, Lin SH, Liu JY, Lin YC. Zeranol down-regulates p53 expression in primary cultured human breast cancer epithelial cells through epigenetic modification. Int J Mol Sci 2011; 12:1519-32. [PMID: 21673905 DOI: 10.3390/ijms12031519] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 01/30/2011] [Accepted: 02/12/2011] [Indexed: 01/10/2023] Open
Abstract
Epidemiological studies have suggested that there are many risk factors associated with breast cancer. Silencing tumor suppressor genes through epigenetic alterations play critical roles in breast cancer initiation, promotion and progression. As a growth promoter, Zeranol (Z) has been approved by the FDA and is widely used to enhance the growth of beef cattle in the United States. However, the safety of Z use as a growth promoter is still under debate. In order to provide more evidence to clarify this critical health issue, the current study investigated the effect of Z on the proliferation of primary cultured human normal and cancerous breast epithelial cells (PCHNBECs and PCHBCECs, respectively) isolated from the same patient using MTS assay, RT-PCR and Western blot analysis. We also conducted an investigation regarding the mechanisms that might be involved. Our results show that Z is more potent to stimulate PCHBCEC growth than PCHNBEC growth. The stimulatory effects of Z on PCHBCECs and PCHBCECs may be mediated by its down-regulating expression of the tumor suppressor gene p53 at the mRNA and protein levels. Further investigation showed that the expression of DNA methylatransferase 1 mRNA and protein levels is up-regulated by treatment with Z in PCHBCECs as compared to PCHNBECs, which suggests a role of Z in epigenetic modification involved in the regulation of p53 gene expression in PCHBCECs. Our experimental results imply the potentially adverse health effect of Z in breast cancer development. Further study is continuing in our laboratory.
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Pal R, Srivastava N, Chopra R, Gochhait S, Gupta P, Prakash N, Agarwal G, Bamezai RN. Investigation of DNA damage response and apoptotic gene methylation pattern in sporadic breast tumors using high throughput quantitative DNA methylation analysis technology. Mol Cancer 2010; 9:303. [PMID: 21092294 DOI: 10.1186/1476-4598-9-303] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 11/23/2010] [Indexed: 01/02/2023] Open
Abstract
Background- Sporadic breast cancer like many other cancers is proposed to be a manifestation of abnormal genetic and epigenetic changes. For the past decade our laboratory has identified genes involved in DNA damage response (DDR), apoptosis and immunesurvelliance pathways to influence sporadic breast cancer risk in north Indian population. Further to enhance our knowledge at the epigenetic level, we performed DNA methylation study involving 17 gene promoter regions belonging to DNA damage response (DDR) and death receptor apoptotic pathway in 162 paired normal and cancerous breast tissues from 81 sporadic breast cancer patients, using a high throughput quantitative DNA methylation analysis technology. Results- The study identified five genes with statistically significant difference between normal and tumor tissues. Hypermethylation of DR5 (P = 0.001), DCR1 (P = 0.00001), DCR2 (P = 0.0000000005) and BRCA2 (P = 0.007) and hypomethylation of DR4 (P = 0.011) in sporadic breast tumor tissues suggested a weak/aberrant activation of the DDR/apoptotic pathway in breast tumorigenesis. Negative correlation was observed between methylation status and transcript expression levels for TRAIL, DR4, CASP8, ATM, CHEK2, BRCA1 and BRCA2 CpG sites. Categorization of the gene methylation with respect to the clinicopathological parameters showed an increase in aberrant methylation pattern in advanced tumors. These uncharacteristic methylation patterns corresponded with decreased death receptor apoptosis (P = 0.047) and DNA damage repair potential (P = 0.004) in advanced tumors. The observation of BRCA2 -26 G/A 5'UTR polymorphism concomitant with the presence of methylation in the promoter region was novel and emerged as a strong candidate for susceptibility to sporadic breast tumors. Conclusion- Our study indicates that methylation of DDR-apoptotic gene promoters in sporadic breast cancer is not a random phenomenon. Progressive epigenetic alterations in advancing tumors result in aberrant DDR-apoptotic pathway thereby promoting tumor development. We propose, since pathological epigenetic changes of the DDR-apoptotic genes are reversible modifications, these could further be targeted for therapeutic interventions.
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Kuo SJ, Chen M, Ma GC, Chen ST, Chang SP, Lin WY, Chen YC, Lee TH, Lin TT, Liu CS. Number of somatic mutations in the mitochondrial D-loop region indicates poor prognosis in breast cancer, independent of TP53 mutation. ACTA ACUST UNITED AC. 2010;201:94-101. [PMID: 20682393 DOI: 10.1016/j.cancergencyto.2010.05.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Revised: 05/19/2010] [Accepted: 05/19/2010] [Indexed: 12/16/2022]
Abstract
The objective of this study was to investigate whether somatic mutations in the mitochondrial DNA (mtDNA) D-loop region correlate with known prognostic factors, namely, age, tumor size, lymph node status, metastasis, tumor-node-metastasis stage, lymphovascular invasion, and status of the progesterone receptor, estrogen receptor, ERBB2 (alias HER2/neu), and TP53 proteins (as determined by immunohistochemistry) and to investigate their relationship, if any, to TP53 mutations in human breast cancer. Thirty breast tumors without BRCA mutation, along with adjacent nontumorous tissues, were genotyped for the mtDNA D-loop region and for the promoter as well as the coding region of the TP53 gene. Clinicopathological parameters were recorded and assessed. In all, 17 somatic mtDNA D-loop mutations were identified, in 13 of 30 tumor samples (43%); two mutations were novel: 544C>T and 16510A>C. Four TP53 mutations were found in six tumor samples (20%), and two (c.437G>A and c.706T>C) were novel. Only progesterone receptor status correlated with the number of somatic mtDNA D-loop mutations (likelihood chi-square test; P < 0.05). Somatic mutations in the mtDNA D-loop and in TP53 were independent of each other (Fisher's exact test; P > 0.05). These results suggest that the number of somatic mtDNA D-loop mutations may be an indicator of poor prognosis through a mechanism independent of TP53.
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Abstract
Real space flight and modeled microgravity conditions result in changes in the expression of genes that control important cellular functions. However, the mechanisms for microgravity-induced gene expression changes are not clear. The epigenetic changes of DNA methylation and chromatin histones modifications are known to regulate gene expression. The objectives of this study were to investigate whether simulated microgravity alters (a) the DNA methylation and histone acetylation, and (b) the expression of DNMT1, DNMT3a, DNMT3b, and HDAC1 genes that regulate epigenetic events. To achieve these objectives, human T-lymphocyte cells were grown in a rotary cell culture system (RCCS) that simulates microgravity, and in parallel under normal gravitational conditions as control. The microgravity-induced DNA methylation changes were detected by methylation sensitive-random amplified polymorphic DNA (MS-RAPD) analysis of genomic DNA. The gene expression was measured by Quantitative Real-time PCR. The expression of DNMT1, DNMT3a, and DNMT3b was found to be increased at 72 h, and decreased at 7 days in microgravity exposed cells. The MS-RAPD analysis revealed that simulated microgravity exposure results in DNA hypomethylation and mutational changes. Gene expression analysis revealed microgravity exposure time-dependent decreased expression of HDAC1. Decreased expression of HDAC1 should result in increased level of acetylated histone H3, however a decreased level of acetylated H3 was observed in microgravity condition, indicating thereby that other HDACs may be involved in regulation of H3 deacetylation. The findings of this study suggest that epigenetic events could be one of the mechanistic bases for microgravity-induced gene expression changes and associated adverse health effects.
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Affiliation(s)
- Kamaleshwar P Singh
- Department of Environmental Toxicology, The Institute of Environmental and Human Health, Texas Tech University, Lubbock, Texas 79409, USA.
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Kim SJ, Kang HS, Jung SY, Min SY, Lee S, Kim SW, Kwon Y, Lee KS, Shin KH, Ro J. Methylation patterns of genes coding for drug-metabolizing enzymes in tamoxifen-resistant breast cancer tissues. J Mol Med (Berl) 2010; 88:1123-31. [PMID: 20628863 DOI: 10.1007/s00109-010-0652-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Revised: 06/22/2010] [Accepted: 06/28/2010] [Indexed: 01/13/2023]
Abstract
The biological mechanisms underlying resistance to tamoxifen are of considerable clinical significance. However, little is known about the correlation between tamoxifen resistance and methylation of genes related to drug-metabolizing enzymes. To address this issue, we examined the methylation pattern and expression of the selected genes coding for drug-metabolizing enzymes, including COMT, CYP1A1, CYP2D6, NAT1, and SULT1A1 in tamoxifen-resistant and control breast cancers. Bisulfite genomic sequencing and methylation-specific PCR were carried out to evaluate the methylation patterns of the five genes from control (n = 74) and tamoxifen-resistant tissues (n = 37) chosen by an age-matched sampling method. Also, end-point reverse transcriptase polymerase chain reaction (RT-PCR) and real-time RT-PCR were performed to determine RNA expression of the genes. Bisulfite genomic sequencing revealed methylation of the NAT1 gene in 25 of the control cancers (33.8%) and 23 of the resistant tumors (62.2%). Of the five genes, only NAT1 showed a significant lower methylation rate in the control group than in the resistant group (p = 0.004). No significant difference of the methylation rate was found in the other four genes including COMT, CYP1A1, CYP2D6, and SULT1A1 (p > 0.05). Furthermore, the expression rate of NAT1 mRNA was lower in the tumors from the resistant group than in control tumors (28.6% vs. 65.2%, p = 0.031). Real-time RT-PCR analysis demonstrated that the NAT1 gene was more down-regulated in resistant tissues than in control group (p = 0.023). Moreover, malignant cells from the resistant cases demonstrated a higher percentage of positive staining for Ki67 (p = 0.001) and cyclin D1 (p = 0.043) than those from the control group. Taken together, the higher methylation rate of the NAT1 gene is related to tamoxifen resistance, and this fact supports the hypothesis that hypermethylation of the NAT1 gene might affect the initiation of tamoxifen resistance.
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Son KS, Kang HS, Kim SJ, Jung SY, Min SY, Lee SY, Kim SW, Kwon Y, Lee KS, Shin KH, Ro J. Hypomethylation of the interleukin-10 gene in breast cancer tissues. Breast 2010; 19:484-8. [PMID: 20646924 DOI: 10.1016/j.breast.2010.05.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Revised: 04/26/2010] [Accepted: 05/24/2010] [Indexed: 11/30/2022] Open
Abstract
The purpose of the study was to evaluate the methylation status of the interleukin-10 (IL-10) gene in breast cancer tissues compared with normal and benign breast disease tissues. Between 2000 and 2001, we used paraffin-embedded specimens of 30 normal, 31 benign and 72 breast cancer tissues from the National Cancer Center, Korea. The methylation patterns of the IL-10 gene were evaluated using bisulfite DNA sequencing and the expression levels of IL-10 mRNA were evaluated using real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) and reverse transcriptase-polymerase chain reaction (RT-PCR). The methylation rates of the IL-10 gene were significantly lower in malignant tumors than in benign and normal tissues (normal; 63.3%, benign; 74.2%, cancer; 45.8%, p = 0.02). The methylation density rates of the IL-10 gene were also significantly lower in malignant tumors (normal; 59.68 ± 7.12%, benign; 48.89 ± 7.45%, cancer; 30.56 ± 4.18%, p = 0.001). Tissues with aberrant methylation of the IL-10 gene showed significantly lower rates of mRNA expression compared with unmethylated cases (12.5% vs. 68.0%, p = 0.012). The mRNA expression of tissues with unmethylated IL-10 was upregulated approximately ten thousand-fold compared to those with IL-10 methylation in the real-time RT-PCR experiment. IL-10 methylation demonstrated a significant association with lower expression of Ki-67 (9.36 ± 2.43 vs. 19.68 ± 3.42, p = 0.02). IL-10 methylation in cancer tissues is lower than that in normal and benign breast tissues, and DNA hypomethylation in the gene influences gene activation. Our data suggest that hypomethylation of the IL-10 gene can be involved in the process of breast carcinogenesis.
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Affiliation(s)
- Keun Su Son
- Department of Life Science, Dongguk University, Seoul 100-715, South Korea
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Corney DC, Hwang CI, Matoso A, Vogt M, Flesken-Nikitin A, Godwin AK, Kamat AA, Sood AK, Ellenson LH, Hermeking H, Nikitin AY. Frequent downregulation of miR-34 family in human ovarian cancers. Clin Cancer Res 2010; 16:1119-28. [PMID: 20145172 DOI: 10.1158/1078-0432.ccr-09-2642] [Citation(s) in RCA: 253] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE The miR-34 family is directly transactivated by tumor suppressor p53, which is frequently mutated in human epithelial ovarian cancer (EOC). We hypothesized that miR-34 expression would be decreased in EOC and that reconstituted miR-34 expression might reduce cell proliferation and invasion of EOC cells. EXPERIMENTAL DESIGNS miR-34 expression was determined by quantitative reverse transcription-PCR and in situ hybridization in a panel of 83 human EOC samples. Functional characterization of miR-34 was accomplished by reconstitution of miR-34 expression in EOC cells with synthetic pre-miR molecules followed by determining changes in proliferation, apoptosis, and invasion. RESULTS miR-34a expression is decreased in 100%, and miR-34b*/c in 72%, of EOC with p53 mutation, whereas miR-34a is also downregulated in 93% of tumors with wild-type p53. Furthermore, expression of miR-34b*/c is significantly reduced in stage IV tumors compared with stage III (P = 0.0171 and P = 0.0029, respectively). Additionally, we observed promoter methylation and copy number variations at mir-34. In situ hybridization showed that miR-34a expression is inversely correlated with MET immunohistochemical staining, consistent with translational inhibition by miR-34a. Finally, miR-34 reconstitution experiments in p53 mutant EOC cells resulted in reduced proliferation, motility, and invasion, the latter of which was dependent on MET expression. CONCLUSIONS Our work suggests that miR-34 family plays an important role in EOC pathogenesis and reduced expression of miR-34b*/c may be particularly important for progression to the most advanced stages. Part of miR-34 effects on motility and invasion may be explained by regulation of MET, which is frequently overexpressed in EOC.
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Affiliation(s)
- David C Corney
- Department of Biomedical Sciences, Cornell University, Ithaca, New York 14853-6401, USA
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