1
|
Yi J, Wu M, Zheng Z, Zhou Q, Li X, Lu Y, Liu P. Integrated analysis of DNA methylome and transcriptome reveals SFRP1 and LIPG as potential drivers of ovarian cancer metastasis. J Gynecol Oncol 2023; 34:e71. [PMID: 37417299 PMCID: PMC10627750 DOI: 10.3802/jgo.2023.34.e71] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 04/17/2023] [Accepted: 05/13/2023] [Indexed: 07/08/2023] Open
Abstract
OBJECTIVE More than 75% of ovarian cancer patients are diagnosed at advanced stages and die of tumor cell metastasis. This study aimed to identify new epigenetic and transcriptomic alterations associated with ovarian cancer metastasis. METHODS Two cell sublines with low- and high-metastasis potentials were derived from the ovarian cancer cell line A2780. Genome-wide DNA methylome and transcriptome profiling were carried out in these two sublines by Reduced Representation Bisulfite Sequencing and RNA-seq technologies. Cell-based assays were conducted to support the clinical findings. RESULTS There are distinct DNA methylation and gene expression patterns between the two cell sublines with low- and high-metastasis potentials. Integrated analysis identified 33 methylation-induced genes potentially involved in ovarian cancer metastasis. The DNA methylation patterns of two of them (i.e., SFRP1 and LIPG) were further validated in human specimens, indicating that they were hypermethylated and downregulated in peritoneal metastatic ovarian carcinoma compared to primary ovarian carcinoma. Patients with lower SFRP1 and LIPG expression tend to have a worse prognosis. Functionally, knockdown of SFRP1 and LIPG promoted cell growth and migration, whereas their overexpression resulted in the opposite effects. In particular, knockdown of SFRP1 could phosphorylate GSK3β and increase β-catenin expression, leading to deregulated activation of the Wnt/β-catenin signaling. CONCLUSION Many systemic and important epigenetic and transcriptomic alterations occur in the progression of ovarian cancer. In particular, epigenetic silencing of SFRP1 and LIPG is a potential driver event in ovarian cancer metastasis. They can be used as prognostic biomarkers and therapeutic targets for ovarian cancer patients.
Collapse
Affiliation(s)
- Jiani Yi
- Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Mengting Wu
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Department of Gynecologic Oncology, Women's Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhihong Zheng
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Department of Gynecologic Oncology, Women's Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Qing Zhou
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Department of Gynecologic Oncology, Women's Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Xufan Li
- Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
| | - Yan Lu
- Zhejiang Provincial Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Department of Gynecologic Oncology, Women's Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
- Cancer Center, Zhejiang University, Hangzhou, China
| | - Pengyuan Liu
- Key Laboratory of Precision Medicine in Diagnosis and Monitoring Research of Zhejiang Province, Sir Run Run Shaw Hospital and Institute of Translational Medicine, Zhejiang University School of Medicine, Hangzhou, China
- Cancer Center, Zhejiang University, Hangzhou, China.
| |
Collapse
|
2
|
Hosein AN, Dangol G, Okumura T, Roszik J, Rajapakshe K, Siemann M, Zaid M, Ghosh B, Monberg M, Guerrero PA, Singhi A, Haymaker CL, Clevers H, Abou-Elkacem L, Woermann SM, Maitra A. Loss of Rnf43 Accelerates Kras-Mediated Neoplasia and Remodels the Tumor Immune Microenvironment in Pancreatic Adenocarcinoma. Gastroenterology 2022; 162:1303-1318.e18. [PMID: 34973294 PMCID: PMC8934289 DOI: 10.1053/j.gastro.2021.12.273] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 11/22/2021] [Accepted: 12/22/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS RNF43 is an E3 ubiquitin ligase that is recurrently mutated in pancreatic ductal adenocarcinoma (PDAC) and precursor cystic neoplasms of the pancreas. The impact of RNF43 mutations on PDAC is poorly understood and autochthonous models have not been characterized sufficiently. In this study, we describe a genetically engineered mouse model (GEMM) of PDAC with conditional expression of oncogenic Kras and deletion of the catalytic domain of Rnf43 in exocrine cells. METHODS We generated Ptf1a-Cre;LSL-KrasG12D;Rnf43flox/flox (KRC) and Ptf1a-Cre; LSL-KrasG12D (KC) mice and animal survival was assessed. KRC mice were sacrificed at 2 months, 4 months, and at moribund status followed by analysis of pancreata by single-cell RNA sequencing. Comparative analyses between moribund KRC and a moribund Kras/Tp53-driven PDAC GEMM (KPC) was performed. Cell lines were isolated from KRC and KC tumors and interrogated by cytokine array analyses, ATAC sequencing, and in vitro drug assays. KRC GEMMs were also treated with an anti-CTLA4 neutralizing antibody with treatment response measured by magnetic response imaging. RESULTS We demonstrate that KRC mice display a marked increase in incidence of high-grade cystic lesions of the pancreas and PDAC compared with KC. Importantly, KRC mice have a significantly decreased survival compared with KC mice. Using single-cell RNA sequencing, we demonstrated that KRC tumor progression is accompanied by a decrease in macrophages, as well as an increase in T and B lymphocytes, with evidence of increased immune checkpoint molecule expression and affinity maturation, respectively. This was in stark contrast to the tumor immune microenvironment observed in the KPC PDAC GEMM. Furthermore, expression of the chemokine CXCL5 was found to be specifically decreased in KRC cancer cells by means of epigenetic regulation and emerged as a putative candidate for mediating the unique KRC immune landscape. CONCLUSIONS The KRC GEMM establishes RNF43 as a bona fide tumor suppressor gene in PDAC. This GEMM features a markedly different immune microenvironment compared with previously reported PDAC GEMMs and puts forth a rationale for an immunotherapy approach in this subset of PDAC cases.
Collapse
Affiliation(s)
- Abdel Nasser Hosein
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
- Department of Internal Medicine, Division of Hematology & Oncology, The University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Advocate Aurora Health, Vince Lombardi Cancer Clinic - Sheboygan, Wisconsin, USA
| | - Gita Dangol
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Takashi Okumura
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Jason Roszik
- Department of Melanoma Medical Oncology Research, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Kimal Rajapakshe
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Megan Siemann
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Mohamed Zaid
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Bidyut Ghosh
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Maria Monberg
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Paola A. Guerrero
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Aatur Singhi
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Cara L Haymaker
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Hans Clevers
- Oncode Institute, Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, University Medical Center Utrecht and Princess Maxima Center, Utrecht, the Netherlands
| | - Lotfi Abou-Elkacem
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Sonja M. Woermann
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Anirban Maitra
- Department of Translational Molecular Pathology, Ahmad Center for Pancreatic Cancer Research, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| |
Collapse
|
3
|
Abstract
The oncosuppressor protein p53 plays a major role in transcriptionally controlling the expression of a number of genes, which in turn regulates many functions in response to DNA damage, oncogene triggering, oxidative, and additional cell stresses. A developing area of interest in p53 is the studies related to its cytoplasmic function(s). Many investigations revealed the significant role of p53 in the cytoplasm, acting in a transcriptional-independent manner in important processes related to cell homeostasis such as; apoptosis, autophagy, metabolism control, drug, and oxidative stress response. The studies on cytoplasmic p53 have shown intricate mechanisms by which posttranslational modifications allow p53 to perform its cytoplasmic functions. A number of ubiquitins, deubiquitins, and small ubiquitin-like proteins, have a pivotal role in controlling cytoplasmic stability and localization. Recently, HOPS/TMUB1 a novel small ubiquitin-like protein has been described as a vital molecule stabilizing p53 half-life, directing it to the mitochondria and favoring p53-mediated apoptosis. Furthermore, HOPS/TMUB1 competing with importin-α lessens p53 nuclear localization, thereby increasing cytoplasmic concentration. HOPS/TMUB1 as p53 modifiers could be attractive candidates to elucidate apoptosis or other important transcriptional-independent functions which are key in cancer research in order to develop new therapeutic approaches.
Collapse
Affiliation(s)
| | - Marilena Castelli
- Department of Experimental Medicine, University of Perugia , Perugia, Italy
| | - Danilo Piobbico
- Department of Experimental Medicine, University of Perugia , Perugia, Italy
| | - Stefania Pieroni
- Department of Experimental Medicine, University of Perugia , Perugia, Italy
| | - Giuseppe Servillo
- Department of Experimental Medicine, University of Perugia , Perugia, Italy
| |
Collapse
|
4
|
Zeng JD, Zhang N, Zhao GJ, Xu LX, Yang Y, Xu XY, Chen MK, Wang HY, Zheng SXF, Li XX. MT1G is Silenced by DNA Methylation and Contributes to the Pathogenesis of Hepatocellular Carcinoma. J Cancer 2018; 9:2807-2816. [PMID: 30123349 PMCID: PMC6096370 DOI: 10.7150/jca.25680] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [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] [Received: 02/23/2018] [Accepted: 06/02/2018] [Indexed: 12/11/2022] Open
Abstract
Using genome-wide screening and TCGA-based data analysis, we identified a DNA methylation-related gene named metallothionein-1G (MT1G), which may play an important role in hepatocellular carcinoma (HCC). In this study, we found that MT1G expression was silenced in 4/6 HCC cell lines and negatively related to aberrant promoter hypermethylation. Its mRNA level was restored with demethylation treatment. Moreover, MT1G downregulation at both the transcriptional and protein level was also detected in 8 pairs of clinical HCC samples compared with its expression in adjacent normal tissues. Ectopic expression of MT1G in silenced HCC cell lines inhibited colony formation, suppressed cell migration and invasion, and repressed xenograft tumor growth in nude mice. In contrast, knockdown of MT1G by short hairpin RNA showed the opposite effect on cell proliferation and the malignant phenotype. Moreover, our data showed that MT1G suppressed tumor invasion and metastasis mainly through regulating the expression of proteins in the matrix metalloproteinase family (MMP) and modulating the epithelial-mesenchymal transition (EMT) process. To our surprise, the data from TCGA showed that hypermethylation of MT1G is associated with good survival of HCC patients. In conclusion, our study demonstrated that MT1G acts as a tumor suppressor gene in HCC development, but its clinical potential in HCC requires further evaluation.
Collapse
Affiliation(s)
- Ju-Deng Zeng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China
| | - Ning Zhang
- Department of Gastroenterology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Gui-Jun Zhao
- Department of Gastroenterology and Hepatology, Inner Mongolia People's Hospital, Hohhot, Inner Mongolia Autonomous Region, China
| | - Li-Xia Xu
- Department of Gastroenterology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yang Yang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China
| | - Xiao-Yi Xu
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China
| | - Meng-Ke Chen
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China
| | - Hui-Yun Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China
| | - Steven Xiao-Feng Zheng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China.,Rutgers Cancer Institute of New Jersey and Department of Pharmacology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Xiao-Xing Li
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, China
| |
Collapse
|
5
|
Bozgeyik I, Yumrutas O, Bozgeyik E. MTUS1, a gene encoding angiotensin-II type 2 (AT2) receptor-interacting proteins, in health and disease, with special emphasis on its role in carcinogenesis. Gene 2017; 626:54-63. [PMID: 28499941 DOI: 10.1016/j.gene.2017.05.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [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: 01/10/2017] [Revised: 05/04/2017] [Accepted: 05/09/2017] [Indexed: 01/13/2023]
Abstract
Loss of tumor suppressor activity is a frequent event in the formation and progression of tumors and has been listed as an important hallmark of cancers. Microtubule-Associated Scaffold Protein 1 (MTUS1) is a candidate tumor suppressor gene which is reported to be frequently down-regulated in a variety of human cancers including pancreas, colon, bladder, head-and-neck, ovarian, breast cancers, gastric, lung cancers. It is also reported to be implicated in several types of pathologies such as cardiac hypertrophy, atherosclerosis, and SLE-like lymphoproliferative diseases. Moreover, MTUS1-encoded proteins are shown to be involved in the regulation of vital cellular processes such as proliferation, differentiation, DNA repair, inflammation, vascular remodeling and senescence. However, the current knowledge is very limited about the role of this gene in human cancers as well as other type diseases. Besides, there is no literature report which summarizes and criticizes the importance of MTUS1 in the cellular processes, especially in the processes of carcinogenesis. Accordingly, in this comprehensive review, we tried to shed light on the role of tumor suppressor MTUS1/ATIP in health and disease, putting special emphasis on its role in the development and progression of human cancers as well as associated molecular mechanisms and the reasons behind MTUS1/ATIP deficiency, which have been not well documented previously.
Collapse
Affiliation(s)
- Ibrahim Bozgeyik
- Adiyaman University, Faculty of Medicine, Department of Medical Biology, Adiyaman, Turkey.
| | - Onder Yumrutas
- Adiyaman University, Faculty of Medicine, Department of Medical Biology, Adiyaman, Turkey
| | - Esra Bozgeyik
- University of Gaziantep, Faculty of Medicine, Department of Medical Biology and Genetics, Gaziantep, Turkey
| |
Collapse
|
6
|
Sei Y, Zhao X, Forbes J, Szymczak S, Li Q, Trivedi A, Voellinger M, Joy G, Feng J, Whatley M, Jones MS, Harper UL, Marx SJ, Venkatesan AM, Chandrasekharappa SC, Raffeld M, Quezado MM, Louie A, Chen CC, Lim RM, Agarwala R, Schäffer AA, Hughes MS, Bailey-Wilson JE, Wank SA. A Hereditary Form of Small Intestinal Carcinoid Associated With a Germline Mutation in Inositol Polyphosphate Multikinase. Gastroenterology 2015; 149:67-78. [PMID: 25865046 PMCID: PMC4858647 DOI: 10.1053/j.gastro.2015.04.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 03/26/2015] [Accepted: 04/02/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND & AIMS Small intestinal carcinoids are rare and difficult to diagnose and patients often present with advanced incurable disease. Although the disease occurs sporadically, there have been reports of family clusters. Hereditary small intestinal carcinoid has not been recognized and genetic factors have not been identified. We performed a genetic analysis of families with small intestinal carcinoids to establish a hereditary basis and find genes that might cause this cancer. METHODS We performed a prospective study of 33 families with at least 2 cases of small intestinal carcinoids. Affected members were characterized clinically and asymptomatic relatives were screened and underwent exploratory laparotomy for suspected tumors. Disease-associated mutations were sought using linkage analysis, whole-exome sequencing, and copy number analyses of germline and tumor DNA collected from members of a single large family. We assessed expression of mutant protein, protein activity, and regulation of apoptosis and senescence in lymphoblasts derived from the cases. RESULTS Familial and sporadic carcinoids are clinically indistinguishable except for the multiple synchronous primary tumors observed in most familial cases. Nearly 34% of asymptomatic relatives older than age 50 were found to have occult tumors; the tumors were cleared surgically from 87% of these individuals (20 of 23). Linkage analysis and whole-exome sequencing identified a germline 4-bp deletion in the gene inositol polyphosphate multikinase (IPMK), which truncates the protein. This mutation was detected in all 11 individuals with small intestinal carcinoids and in 17 of 35 family members whose carcinoid status was unknown. Mutant IPMK had reduced kinase activity and nuclear localization, compared with the full-length protein. This reduced activation of p53 and increased cell survival. CONCLUSIONS We found that small intestinal carcinoids can occur as an inherited autosomal-dominant disease. The familial form is characterized by multiple synchronous primary tumors, which might account for 22%-35% of cases previously considered sporadic. Relatives of patients with familial carcinoids should be screened to detect curable early stage disease. IPMK haploinsufficiency promotes carcinoid tumorigenesis.
Collapse
Affiliation(s)
- Yoshitatsu Sei
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Xilin Zhao
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Joanne Forbes
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Silke Szymczak
- Computational and Statistical Genomics Branch, NHGRI, National Institutes of Health, Bethesda, MD, USA
| | - Qing Li
- Computational and Statistical Genomics Branch, NHGRI, National Institutes of Health, Bethesda, MD, USA
| | - Apurva Trivedi
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Mark Voellinger
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Grishma Joy
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Jianying Feng
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Millie Whatley
- Nuclear Medicine Division, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - MaryPat Sussex Jones
- Genomics Core/Genome Technology Branch, NHGRI, National Institutes of Health, Bethesda, MD, USA
| | - Ursula L. Harper
- Genomics Core/Genome Technology Branch, NHGRI, National Institutes of Health, Bethesda, MD, USA
| | - Stephen J. Marx
- Metabolic Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Aradhana M. Venkatesan
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | | | - Mark Raffeld
- Laboratory of Pathology, NCI, National Institutes of Health, Bethesda, MD, USA
| | - Martha M. Quezado
- Laboratory of Pathology, NCI, National Institutes of Health, Bethesda, MD, USA
| | - Adeline Louie
- Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Clara C. Chen
- Nuclear Medicine Division, Clinical Center, National Institutes of Health, Bethesda, MD, USA
| | - Ramona M. Lim
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA
| | - Richa Agarwala
- Information Engineering Branch, NCBI, NLM, National Institutes of Health, Bethesda, MD, USA
| | - Alejandro A. Schäffer
- Computational Biology Branch, NCBI, NLM, National Institutes of Health, Bethesda, MD, USA
| | | | - Joan E. Bailey-Wilson
- Computational and Statistical Genomics Branch, NHGRI, National Institutes of Health, Bethesda, MD, USA
| | - Stephen A. Wank
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD, USA,To whom correspondence should be addressed: Stephen A. Wank, M.D., Address: DDB/NIDDK/NIH, 10/9C-101, Bethesda, MD 20892, , Phone: (301) 402-3704, Fax: (301) 480-7476
| |
Collapse
|
7
|
Sun F, Xiao Y, Qu Z. Oncovirus Kaposi sarcoma herpesvirus (KSHV) represses tumor suppressor PDLIM2 to persistently activate nuclear factor κB (NF-κB) and STAT3 transcription factors for tumorigenesis and tumor maintenance. J Biol Chem 2015; 290:7362-8. [PMID: 25681443 DOI: 10.1074/jbc.c115.637918] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Kaposi sarcoma herpesvirus (KSHV) is the most common cause of malignancies among AIDS patients. However, how KSHV induces tumorigenesis remains largely unknown. Here, we demonstrate that one important mechanism underlying the tumorigenesis of KSHV is through transcriptional repression of the tumor suppressor gene PDZ-LIM domain-containing protein 2 (PDLIM2). PDLIM2 expression is repressed in KSHV-transformed human umbilical vascular endothelial cells as well as in KSHV-associated cancer cell lines and primary tumors. Importantly, PDLIM2 repression is essential for KSHV-induced persistent activation of nuclear factor κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) and subsequent tumorigenesis and tumor maintenance. Our mechanistic studies indicate that PDLIM2 repression by KSHV involves DNA methylation. Notably, the epigenetic repression of PDLIM2 can be reversed by 5-aza-2-deoxycytidine and vitamin D to suppress KSHV-associated cancer cell growth. These studies not only improve our understanding of KSHV pathogenesis but also provide immediate therapeutic strategies for KSHV-mediated cancers, particularly those associated with AIDS.
Collapse
Affiliation(s)
- Fan Sun
- From the University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, and the Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Yadong Xiao
- From the University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, and
| | - Zhaoxia Qu
- From the University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232, and the Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| |
Collapse
|
8
|
Jeansonne D, DeLuca M, Marrero L, Lassak A, Pacifici M, Wyczechowska D, Wilk A, Reiss K, Peruzzi F. Anti-tumoral effects of miR-3189-3p in glioblastoma. J Biol Chem 2015; 290:8067-80. [PMID: 25645911 DOI: 10.1074/jbc.m114.633081] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [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: 01/09/2023] Open
Abstract
Glioblastoma is one of the most aggressive brain tumors. We have previously found up-regulation of growth differentiation factor 15 (GDF15) in glioblastoma cells treated with the anticancer agent fenofibrate. Sequence analysis of GDF15 revealed the presence of a microRNA, miR-3189, in the single intron. We then asked whether miR-3189 was expressed in clinical samples and whether it was functional in glioblastoma cells. We found that expression of miR-3189-3p was down-regulated in astrocytoma and glioblastoma clinical samples compared with control brain tissue. In vitro, the functionality of miR-3189-3p was tested by RNA-binding protein immunoprecipitation, and miR-3189-3p coimmunoprecipitated with Argonaute 2 together with two of its major predicted gene targets, the SF3B2 splicing factor and the guanine nucleotide exchange factor p63RhoGEF. Overexpression of miR-3189-3p resulted in a significant inhibition of cell proliferation and migration through direct targeting of SF3B2 and p63RhoGEF, respectively. Interestingly, miR-3189-3p levels were increased by treatment of glioblastoma cells with fenofibrate, a lipid-lowering drug with multiple anticancer activities. The attenuated expression of miR-3189-3p in clinical samples paralleled the elevated expression of SF3B2, which could contribute to the activation of SF3B2 growth-promoting pathways in these tumors. Finally, miR-3189-3p-mediated inhibition of tumor growth in vivo further supported the function of this microRNA as a tumor suppressor.
Collapse
Affiliation(s)
- Duane Jeansonne
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | - Mariacristina DeLuca
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | | | - Adam Lassak
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | - Marco Pacifici
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | - Dorota Wyczechowska
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | - Anna Wilk
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | - Krzysztof Reiss
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| | - Francesca Peruzzi
- From the Department of Medicine and the Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, Louisiana 70112
| |
Collapse
|
9
|
Okino Y, Machida Y, Frankland-Searby S, Machida YJ. BRCA1-associated protein 1 (BAP1) deubiquitinase antagonizes the ubiquitin-mediated activation of FoxK2 target genes. J Biol Chem 2014; 290:1580-91. [PMID: 25451922 DOI: 10.1074/jbc.m114.609834] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [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: 11/06/2022] Open
Abstract
BRCA1-associated protein 1 (BAP1), which is frequently mutated in cancer, functions as a deubiquitinase (DUB) for histone H2A. Although BAP1 interacts with a transcriptional regulator, HCF-1, and transcription factors FoxK1 and FoxK2, how BAP1 controls gene expression remains unclear. This study investigates the importance of BAP1 DUB activity and the interactions with FoxK2 and HCF-1 in the regulation of FoxK2 target genes. We show that FoxK2 recruits BAP1 to the target genes through the forkhead-associated domain, which interacts with Thr(P)-493 on BAP1. BAP1, in turn, recruits HCF-1, thereby forming a ternary complex in which BAP1 bridges FoxK2 and HCF-1. BAP1 represses FoxK2 target genes, and this effect requires BAP1 DUB activity but not interaction with HCF-1. Importantly, BAP1 depletion causes up-regulation of FoxK2 target genes only in the presence of the Ring1B-Bmi1 complex, an E3 ubiquitin ligase for histone H2A, indicating an antagonizing role of BAP1 against Ring1B-Bmi1. Our findings suggest that BAP1 deficiency causes increased expression of target genes in a Ring1B-Bmi1-dependent manner.
Collapse
Affiliation(s)
| | | | - Sarah Frankland-Searby
- Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55905
| | - Yuichi J Machida
- From the Departments of Oncology and Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55905
| |
Collapse
|
10
|
Ou Y, Wang SJ, Jiang L, Zheng B, Gu W. p53 Protein-mediated regulation of phosphoglycerate dehydrogenase (PHGDH) is crucial for the apoptotic response upon serine starvation. J Biol Chem 2014; 290:457-66. [PMID: 25404730 DOI: 10.1074/jbc.m114.616359] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although p53 is frequently mutated in human cancers, about 80% of human melanomas retain wild-type p53. Here we report that PHGDH, the key metabolic enzyme that catalyzes the rate-limiting step of the serine biosynthesis pathway, is a target of p53 in human melanoma cells. p53 suppresses PHGDH expression and inhibits de novo serine biosynthesis. Notably, upon serine starvation, p53-mediated cell death is enhanced dramatically in response to Nutlin-3 treatment. Moreover, PHGDH has been found recently to be amplified frequently in human melanomas. We found that PHGDH overexpression significantly suppresses the apoptotic response, whereas RNAi-mediated knockdown of endogenous PHGDH promotes apoptosis under the same treatment. These results demonstrate an important role of p53 in regulating the serine biosynthesis pathway through suppressing PHGDH expression and reveal serine deprivation as a novel approach to sensitize p53-mediated apoptotic responses in human melanoma cells.
Collapse
Affiliation(s)
- Yang Ou
- From the Institute for Cancer Genetics and Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| | - Shang-Jui Wang
- From the Institute for Cancer Genetics and Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| | - Le Jiang
- From the Institute for Cancer Genetics and Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| | - Bin Zheng
- the Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129
| | - Wei Gu
- From the Institute for Cancer Genetics and Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, New York 10032 and
| |
Collapse
|
11
|
Huang G, Stock C, Bommeljé CC, Weeda VB, Shah K, Bains S, Buss E, Shaha M, Rechler W, Ramanathan SY, Singh B. SCCRO3 (DCUN1D3) antagonizes the neddylation and oncogenic activity of SCCRO (DCUN1D1). J Biol Chem 2014; 289:34728-42. [PMID: 25349211 DOI: 10.1074/jbc.m114.585505] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The activity of cullin-RING type ubiquitination E3 ligases is regulated by neddylation, a process analogous to ubiquitination that culminates in covalent attachment of the ubiquitin-like protein Nedd8 to cullins. As a component of the E3 for neddylation, SCCRO/DCUN1D1 plays a key regulatory role in neddylation and, consequently, cullin-RING ligase activity. The essential contribution of SCCRO to neddylation is to promote nuclear translocation of the cullin-ROC1 complex. The presence of a myristoyl sequence in SCCRO3, one of four SCCRO paralogues present in humans that localizes to the membrane, raises questions about its function in neddylation. We found that although SCCRO3 binds to CAND1, cullins, and ROC1, it does not efficiently bind to Ubc12, promote cullin neddylation, or conform to the reaction processivity paradigms, suggesting that SCCRO3 does not have E3 activity. Expression of SCCRO3 inhibits SCCRO-promoted neddylation by sequestering cullins to the membrane, thereby blocking its nuclear translocation. Moreover, SCCRO3 inhibits SCCRO transforming activity. The inhibitory effects of SCCRO3 on SCCRO-promoted neddylation and transformation require both an intact myristoyl sequence and PONY domain, confirming that membrane localization and binding to cullins are required for in vivo functions. Taken together, our findings suggest that SCCRO3 functions as a tumor suppressor by antagonizing the neddylation activity of SCCRO.
Collapse
Affiliation(s)
- Guochang Huang
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Cameron Stock
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Claire C Bommeljé
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Víola B Weeda
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Kushyup Shah
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Sarina Bains
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Elizabeth Buss
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Manish Shaha
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Willi Rechler
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Suresh Y Ramanathan
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Bhuvanesh Singh
- From the Department of Surgery, Laboratory of Epithelial Cancer Biology, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| |
Collapse
|
12
|
Hu L, Huang H, Li J, Yin MX, Lu Y, Wu W, Zeng R, Jiang J, Zhao Y, Zhang L. Drosophila casein kinase 2 (CK2) promotes warts protein to suppress Yorkie protein activity for growth control. J Biol Chem 2014; 289:33598-607. [PMID: 25320084 DOI: 10.1074/jbc.m114.580456] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [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: 12/28/2022] Open
Abstract
Drosophila Hippo signaling regulates Wts activity to phosphorylate and inhibit Yki in order to control tissue growth. CK2 is widely expressed and involved in a variety of signaling pathways. In this study we report that Drosophila CK2 promotes Wts activity to phosphorylate and inhibit Yki activity, which is independent of Hpo-induced Wts promotion. In vivo, CK2 overexpression suppresses hpo mutant-induced expanded (Ex) up-regulation and overgrowth phenotype, whereas it cannot affect wts mutant. Consistent with this, knockdown of CK2 up-regulates Hpo pathway target expression. We also found that Drosophila CK2 is essential for tissue growth as a cell death inhibitor as knockdown of CK2 in the developing disc induces severe growth defects as well as caspase3 signals. Taken together, our results uncover a dual role of CK2; although its major role is promoting cell survive, it may potentially be a growth inhibitor as well.
Collapse
Affiliation(s)
- Lianxin Hu
- From the State Key Laboratory of Cell Biology and
| | | | - Jinhui Li
- From the State Key Laboratory of Cell Biology and
| | - Meng-Xin Yin
- From the State Key Laboratory of Cell Biology and
| | - Yi Lu
- From the State Key Laboratory of Cell Biology and
| | - Wenqing Wu
- From the State Key Laboratory of Cell Biology and
| | - Rong Zeng
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Yue-Yang Road, Shanghai 200031, China and
| | - Jin Jiang
- Department of Developmental Biology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Yun Zhao
- From the State Key Laboratory of Cell Biology and
| | - Lei Zhang
- From the State Key Laboratory of Cell Biology and
| |
Collapse
|
13
|
Abstract
In humans, colorectal cancer is often initiated through APC loss of function, which leads to crypt hyperplasia and polyposis driven by unrestricted canonical Wnt signaling. Such polyps typically arise in the colorectal region and are at risk of transforming to invasive adenocarcinomas. Although colorectal cancer is the third most common cause of cancer-related death worldwide, the processes impacting initiation, transformation, and invasion are incompletely understood. Murine APC(Min/+) mutants are often used to model colorectal cancers; however, they develop nonmetastatic tumors confined largely to the small intestine and are thus not entirely representative of the human disease. APC(Min/+) alleles can collaborate with mutations impacting other pathways to recapitulate some aspects of human colorectal cancer. To this end, we assessed APC(Min/+)-induced polyposis following somatic loss of the homeodomain transcription factor Cdx2, alone or with a Cdx1 null allele, in the adult gastrointestinal tract. APC(Min/+)-Cdx2 mutants recapitulated several aspects of human colorectal cancer, including an invasive phenotype. Notably, the concomitant loss of Cdx1 led to a significant increase in the incidence of tumors in the distal colon, relative to APC(Min/+)-Cdx2 offspring, demonstrating a previously unrecognized role for this transcription factor in colorectal tumorigenesis. These findings underscore previously unrecognized roles for Cdx members in intestinal tumorigenesis.
Collapse
Affiliation(s)
- Alexa Hryniuk
- From the Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Stephanie Grainger
- From the Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Joanne G A Savory
- From the Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - David Lohnes
- From the Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| |
Collapse
|
14
|
Abstract
The p53-mediated responses to DNA damage and the Hedgehog (Hh) signaling pathway are each recurrently dysregulated in many types of human cancer. Here we describe PTCH53, a p53 target gene that is homologous to the tumor suppressor gene PTCH1 and can function as a repressor of Hh pathway activation. PTCH53 (previously designated PTCHD4) was highly responsive to p53 in vitro and was among a small number of genes that were consistently expressed at reduced levels in diverse TP53 mutant cell lines and human tumors. Increased expression of PTCH53 inhibited canonical Hh signaling by the G protein-coupled receptor SMO. PTCH53 thus delineates a novel, inducible pathway by which p53 can repress tumorigenic Hh signals.
Collapse
Affiliation(s)
- Jon H Chung
- From the Department of Radiation Oncology and Molecular Radiation Sciences, The Kimmel Cancer Center at Johns Hopkins, Baltimore, Maryland 21231
| | - Andrew R Larsen
- From the Department of Radiation Oncology and Molecular Radiation Sciences, The Kimmel Cancer Center at Johns Hopkins, Baltimore, Maryland 21231
| | - Evan Chen
- From the Department of Radiation Oncology and Molecular Radiation Sciences, The Kimmel Cancer Center at Johns Hopkins, Baltimore, Maryland 21231
| | - Fred Bunz
- From the Department of Radiation Oncology and Molecular Radiation Sciences, The Kimmel Cancer Center at Johns Hopkins, Baltimore, Maryland 21231
| |
Collapse
|
15
|
Abstract
Ras is the most frequently activated oncogene found in human cancer, but its mechanisms of action remain only partially understood. Ras activates multiple signaling pathways to promote transformation. However, Ras can also exhibit a potent ability to induce growth arrest and death. NORE1A (RASSF5) is a direct Ras effector that acts as a tumor suppressor by promoting apoptosis and cell cycle arrest. Expression of NORE1A is frequently lost in human tumors, and its mechanism of action remains unclear. Here we show that NORE1A forms a direct, Ras-regulated complex with β-TrCP, the substrate recognition component of the SCF(β-TrCP) ubiquitin ligase complex. This interaction allows Ras to stimulate the ubiquitin ligase activity of SCF(β-TrCP) toward its target β-catenin, resulting in degradation of β-catenin by the 26 S proteasome. However, the action of Ras/NORE1A/β-TrCP is substrate-specific because IκB, another substrate of SCF(β-TrCP), is not sensitive to NORE1A-promoted degradation. We identify a completely new signaling mechanism for Ras that allows for the specific regulation of SCF(β-TrCP) targets. We show that the NORE1A levels in a cell may dictate the effects of Ras on the Wnt/β-catenin pathway. Moreover, because NORE1A expression is frequently impaired in tumors, we provide an explanation for the observation that β-TrCP can act as a tumor suppressor or an oncogene in different cell systems.
Collapse
Affiliation(s)
- M Lee Schmidt
- From the Molecular Targets Group, James Graham Brown Cancer Center, Departments of Biochemistry and Molecular Biology
| | | | - Geoffrey J Clark
- Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
| |
Collapse
|
16
|
Kobayashi D, Hirayama M, Komohara Y, Mizuguchi S, Wilson Morifuji M, Ihn H, Takeya M, Kuramochi A, Araki N. Translationally controlled tumor protein is a novel biological target for neurofibromatosis type 1-associated tumors. J Biol Chem 2014; 289:26314-26326. [PMID: 25092287 DOI: 10.1074/jbc.m114.568253] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) is an autosomal dominant disease that predisposes individuals to develop benign neurofibromas and malignant peripheral nerve sheath tumors (MPNSTs). Due to the lack of information on the molecular mechanism of NF1-associated tumor pathogenesis or biomarkers/therapeutic targets, an effective treatment for NF1 tumors has not been established. In this study, the novel NF1-associated protein, translationally controlled tumor protein (TCTP), was identified by integrated proteomics and found to be up-regulated via activated MAPK/PI3K-AKT signaling in response to growth factors in NF1-deficient Schwann cells. Immunohistochemical analysis of NF1-associated tumors revealed that the TCTP expression level correlated with tumorigenicity. In NF1-deficient MPNST cells, TCTP protein but not mRNA was down-regulated by NF1 GTPase-activating protein-related domain or MAPK/PI3K inhibitors, and this correlated with suppression of mammalian target of rapamycin (mTOR) signaling. mTOR inhibition by rapamycin also down-regulated TCTP protein expression, whereas knockdown or overexpression of TCTP suppressed or activated mTOR signaling, respectively, and affected cell viability. These results suggest that a positive feedback loop between TCTP and mTOR contributes to NF1-associated tumor formation. Last, the anti-tumor effect of artesunate, which binds to and degrades TCTP, was evaluated. Artesunate significantly suppressed the viability of MPNST cells but not normal Schwann cells, and the TCTP level inversely correlated with artesunate sensitivity. Moreover, combinational use of artesunate and rapamycin enhanced the cytotoxic effect on MPNST cells. These findings suggest that TCTP is functionally implicated in the progression of NF1-associated tumors and could serve as a biological target for their therapy.
Collapse
Affiliation(s)
- Daiki Kobayashi
- Department of Tumor Genetics and Biology, Kumamoto University, Kumamoto 860-8556, Japan
| | - Mio Hirayama
- Department of Tumor Genetics and Biology, Kumamoto University, Kumamoto 860-8556, Japan
| | - Yoshihiro Komohara
- Department of Cell Pathology, Graduate School of Medical Sciences, and Kumamoto University, Kumamoto 860-8556, Japan
| | - Souhei Mizuguchi
- Department of Tumor Genetics and Biology, Kumamoto University, Kumamoto 860-8556, Japan
| | | | - Hironobu Ihn
- Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto 860-8556, Japan and
| | - Motohiro Takeya
- Department of Cell Pathology, Graduate School of Medical Sciences, and Kumamoto University, Kumamoto 860-8556, Japan
| | - Akira Kuramochi
- Department of Dermatology, Saitama Medical University, Saitama 350-0495, Japan
| | - Norie Araki
- Department of Tumor Genetics and Biology, Kumamoto University, Kumamoto 860-8556, Japan.
| |
Collapse
|
17
|
Yang CH, Yue J, Pfeffer SR, Fan M, Paulus E, Hosni-Ahmed A, Sims M, Qayyum S, Davidoff AM, Handorf CR, Pfeffer LM. MicroRNA-21 promotes glioblastoma tumorigenesis by down-regulating insulin-like growth factor-binding protein-3 (IGFBP3). J Biol Chem 2014; 289:25079-87. [PMID: 25059666 DOI: 10.1074/jbc.m114.593863] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Despite advances in surgery, imaging, chemotherapy, and radiation, patients with glioblastoma multiforme (GBM), the most common histological subtype of glioma, have an especially dismal prognosis; >70% of GBM patients die within 2 years of diagnosis. In many human cancers, the microRNA miR-21 is overexpressed, and accumulating evidence indicates that it functions as an oncogene. Here, we report that miR-21 is overexpressed in human GBM cell lines and tumor tissue. Moreover, miR-21 expression in GBM patient samples is inversely correlated with patient survival. Knockdown of miR-21 in GBM cells inhibited cell proliferation in vitro and markedly inhibited tumor formation in vivo. A number of known miR-21 targets have been identified previously. By microarray analysis, we identified and validated insulin-like growth factor (IGF)-binding protein-3 (IGFBP3) as a novel miR-21 target gene. Overexpression of IGFBP3 in glioma cells inhibited cell proliferation in vitro and inhibited tumor formation of glioma xenografts in vivo. The critical role that IGFBP3 plays in miR-21-mediated actions was demonstrated by a rescue experiment, in which IGFBP3 knockdown in miR-21KD glioblastoma cells restored tumorigenesis. Examination of tumors from GBM patients showed that there was an inverse relationship between IGFBP3 and miR-21 expression and that increased IGFBP3 expression correlated with better patient survival. Our results identify IGFBP3 as a novel miR-21 target gene in glioblastoma and suggest that the oncogenic miRNA miR-21 down-regulates the expression of IGFBP3, which acts as a tumor suppressor in human glioblastoma.
Collapse
Affiliation(s)
- Chuan He Yang
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Junming Yue
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Susan R Pfeffer
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Meiyun Fan
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | | | - Amira Hosni-Ahmed
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Michelle Sims
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Sohail Qayyum
- From the Departments of Pathology and Laboratory Medicine and
| | - Andrew M Davidoff
- From the Departments of Pathology and Laboratory Medicine and Department of Surgery, St. Jude Children's Research Hospital, Memphis, Tennessee 38103
| | - Charles R Handorf
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Lawrence M Pfeffer
- From the Departments of Pathology and Laboratory Medicine and the Center for Cancer Research, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| |
Collapse
|
18
|
Zhang L, Wei Y, Pushel I, Heinze K, Elenbaas J, Henry RW, Arnosti DN. Integrated stability and activity control of the Drosophila Rbf1 retinoblastoma protein. J Biol Chem 2014; 289:24863-73. [PMID: 25049232 DOI: 10.1074/jbc.m114.586818] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [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: 11/06/2022] Open
Abstract
The retinoblastoma (RB) family transcriptional corepressors regulate diverse cellular events including cell cycle, senescence, and differentiation. The activity and stability of these proteins are mediated by post-translational modifications; however, we lack a general understanding of how distinct modifications coordinately impact both of these properties. Previously, we showed that protein turnover and activity are tightly linked through an evolutionarily conserved C-terminal instability element (IE) in the Drosophila RB-related protein Rbf1; surprisingly, mutant proteins with enhanced stability were less, not more active. To better understand how activity and turnover are controlled in this model RB protein, we assessed the impact of Cyclin-Cdk kinase regulation on Rbf1. An evolutionarily conserved N-terminal threonine residue is required for Cyclin-Cdk response and showed a dominant impact on turnover and activity; however, specific residues in the C-terminal IE differentially impacted Rbf1 activity and turnover, indicating an additional level of regulation. Strikingly, specific IE mutations that impaired turnover but not activity induced dramatic developmental phenotypes in the Drosophila eye. Mutation of the highly conserved Lys-774 residue induced hypermorphic phenotypes that mimicked the loss of phosphorylation control; mutation of the corresponding codon of the human RBL2 gene has been reported in lung tumors. Our data support a model in which closely intermingled residues within the conserved IE govern protein turnover, presumably through interactions with E3 ligases, and protein activity via contacts with E2F transcription partners. Such functional relationships are likely to similarly impact mammalian RB family proteins, with important implications for development and disease.
Collapse
Affiliation(s)
- Liang Zhang
- From the Cell and Molecular Biology Program and
| | - Yiliang Wei
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - Irina Pushel
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - Karolin Heinze
- the Biochemistry and Molecular Biology Program, Friedrich-Schiller University Jena, D-07743 Jena, Germany
| | - Jared Elenbaas
- the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - R William Henry
- From the Cell and Molecular Biology Program and the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| | - David N Arnosti
- From the Cell and Molecular Biology Program and the Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824-1319 and
| |
Collapse
|
19
|
Kirschner KM, Braun JFW, Jacobi CL, Rudigier LJ, Persson AB, Scholz H. Amine oxidase copper-containing 1 (AOC1) is a downstream target gene of the Wilms tumor protein, WT1, during kidney development. J Biol Chem 2014; 289:24452-62. [PMID: 25037221 DOI: 10.1074/jbc.m114.564336] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Amine oxidase copper-containing 1 (AOC1; formerly known as amiloride-binding protein 1) is a secreted glycoprotein that catalyzes the degradation of putrescine and histamine. Polyamines and their diamine precursor putrescine are ubiquitous to all organisms and fulfill pivotal functions in cell growth and proliferation. Despite the importance of AOC1 in regulating polyamine breakdown, very little is known about the molecular mechanisms that control its expression. We report here that the Wilms tumor protein, WT1, which is necessary for normal kidney development, activates transcription of the AOC1 gene. Expression of a firefly luciferase reporter under control of the proximal AOC1 promoter was significantly enhanced by co-transfection of a WT1 expression construct. Binding of WT1 protein to a cis-regulatory element in the AOC1 promoter was confirmed by electrophoretic mobility shift assay and chromatin immunoprecipitation. Antisense inhibition of WT1 protein translation strongly reduced Aoc1 transcripts in cultured murine embryonic kidneys and gonads. Aoc1 mRNA levels correlated with WT1 protein in several cell lines. Double immunofluorescent staining revealed a co-expression of WT1 and AOC1 proteins in the developing genitourinary system of mice and rats. Strikingly, induced changes in polyamine homeostasis affected branching morphogenesis of cultured murine embryonic kidneys in a developmental stage-specific manner. These findings suggest that WT1-dependent control of polyamine breakdown, which is mediated by changes in AOC1 expression, has a role in kidney organogenesis.
Collapse
Affiliation(s)
- Karin M Kirschner
- From the Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Julian F W Braun
- From the Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Charlotte L Jacobi
- From the Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Lucas J Rudigier
- From the Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Anja Bondke Persson
- From the Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Holger Scholz
- From the Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| |
Collapse
|
20
|
Noorlag R, van Kempen PMW, Moelans CB, de Jong R, Blok LER, Koole R, Grolman W, van Diest PJ, van Es RJJ, Willems SM. Promoter hypermethylation using 24-gene array in early head and neck cancer: better outcome in oral than in oropharyngeal cancer. Epigenetics 2014; 9:1220-7. [PMID: 25147921 DOI: 10.4161/epi.29785] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [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: 12/23/2022] Open
Abstract
Silencing of tumor suppressor genes (TSGs) by DNA promoter hypermethylation is an early event in carcinogenesis and a potential target for personalized cancer treatment. In head and neck cancer, little is known about the role of promoter hypermethylation in survival. Using methylation specific multiplex ligation-dependent probe amplification (MS-MLPA) we investigated the role of promoter hypermethylation of 24 well-described genes (some of which are classic TSGs), which are frequently methylated in different cancer types, in 166 HPV-negative early oral squamous cell carcinomas (OSCC), and 51 HPV-negative early oropharyngeal squamous cell carcinomas (OPSCC) in relation to clinicopathological features and survival. Early OSCC showed frequent promoter hypermethylation in RARB (31% of cases), CHFR (20%), CDH13 (13%), DAPK1 (12%), and APC (10%). More hypermethylation (≥ 2 genes) independently correlated with improved disease specific survival (hazard ratio 0.17, P = 0.014) in early OSCC and could therefore be used as prognostic biomarker. Early OPSCCs showed more hypermethylation of CDH13 (58%), TP73 (14%), and total hypermethylated genes. Hypermethylation of two or more genes has a significantly different effect on survival in OPSCC compared with OSCC, with a trend toward worse instead of better survival. This could have a biological explanation, which deserves further investigation and could possibly lead to more stratified treatment in the future.
Collapse
Affiliation(s)
- Rob Noorlag
- Department of Oral and Maxillofacial Surgery; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Pauline M W van Kempen
- Department of Otorhinolaryngology; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Cathy B Moelans
- Department of Pathology; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Rick de Jong
- Department of Pathology; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Laura E R Blok
- Department of Pathology; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Ronald Koole
- Department of Oral and Maxillofacial Surgery; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Wilko Grolman
- Department of Otorhinolaryngology; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Paul J van Diest
- Department of Pathology; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Robert J J van Es
- Department of Oral and Maxillofacial Surgery; University Medical Center Utrecht; Utrecht, the Netherlands
| | - Stefan M Willems
- Department of Pathology; University Medical Center Utrecht; Utrecht, the Netherlands
| |
Collapse
|
21
|
Zhu B, Ferry CH, Markell LK, Blazanin N, Glick AB, Gonzalez FJ, Peters JM. The nuclear receptor peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) promotes oncogene-induced cellular senescence through repression of endoplasmic reticulum stress. J Biol Chem 2014; 289:20102-19. [PMID: 24898257 DOI: 10.1074/jbc.m114.551069] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [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: 11/06/2022] Open
Abstract
Endoplasmic reticulum (ER) stress and ER stress-associated unfolded protein response (UPR) can promote cancer cell survival, but it remains unclear whether they can influence oncogene-induced senescence. The present study examined the role of ER stress in senescence using oncogene-dependent models. Increased ER stress attenuated senescence in part by up-regulating phosphorylated protein kinase B (p-AKT) and decreasing phosphorylated extracellular signal-regulated kinase (p-ERK). A positive feed forward loop between p-AKT, ER stress, and UPR was discovered whereby a transient increase of ER stress caused reduced senescence and promotion of tumorigenesis. Decreased ER stress was further correlated with increased senescence in both mouse and human tumors. Interestingly, H-RAS-expressing Pparβ/δ null cells and tumors having increased cell proliferation exhibited enhanced ER stress, decreased cellular senescence, and/or enhanced tumorigenicity. Collectively, these results demonstrate a new role for ER stress and UPR that attenuates H-RAS-induced senescence and suggest that PPARβ/δ can repress this oncogene-induced ER stress to promote senescence in accordance with its role as a tumor modifier that suppresses carcinogenesis.
Collapse
Affiliation(s)
- Bokai Zhu
- From the Department of Veterinary and Biomedical Sciences and The Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania 16802 and
| | - Christina H Ferry
- From the Department of Veterinary and Biomedical Sciences and The Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania 16802 and
| | - Lauren K Markell
- From the Department of Veterinary and Biomedical Sciences and The Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania 16802 and
| | - Nicholas Blazanin
- From the Department of Veterinary and Biomedical Sciences and The Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania 16802 and
| | - Adam B Glick
- From the Department of Veterinary and Biomedical Sciences and The Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania 16802 and
| | - Frank J Gonzalez
- the Laboratory of Metabolism, NCI, National Institutes of Health, Bethesda, Maryland 20892
| | - Jeffrey M Peters
- From the Department of Veterinary and Biomedical Sciences and The Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, Pennsylvania 16802 and
| |
Collapse
|
22
|
Fay MM, Clegg JM, Uchida KA, Powers MA, Ullman KS. Enhanced arginine methylation of programmed cell death 4 protein during nutrient deprivation promotes tumor cell viability. J Biol Chem 2014; 289:17541-52. [PMID: 24764298 DOI: 10.1074/jbc.m113.541300] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The role of programmed cell death 4 (PDCD4) in tumor biology is context-dependent. PDCD4 is described as a tumor suppressor, but its coexpression with protein arginine methyltransferase 5 (PRMT5) promotes accelerated tumor growth. Here, we report that PDCD4 is methylated during nutrient deprivation. Methylation occurs because of increased stability of PDCD4 protein as well as increased activity of PRMT5 toward PDCD4. During nutrient deprivation, levels of methylated PDCD4 promote cell viability, which is dependent on an enhanced interaction with eIF4A. Upon recovery from nutrient deprivation, levels of methylated PDCD4 are regulated by phosphorylation, which controls both the localization and stability of methylated PDCD4. This study reveals that, in response to particular environmental cues, the role of PDCD4 is up-regulated and is advantageous for cell viability. These findings suggest that the methylated form of PDCD4 promotes tumor viability during nutrient deprivation, ultimately allowing the tumor to grow more aggressively.
Collapse
Affiliation(s)
- Marta M Fay
- From the Oncological Sciences Department, Huntsman Cancer Institute and
| | - James M Clegg
- From the Oncological Sciences Department, Huntsman Cancer Institute and
| | - Kimberly A Uchida
- From the Oncological Sciences Department, Huntsman Cancer Institute and Department of Bioengineering, University of Utah, Salt Lake City, Utah 84112
| | - Matthew A Powers
- From the Oncological Sciences Department, Huntsman Cancer Institute and
| | | |
Collapse
|
23
|
Waight JD, Banik D, Griffiths EA, Nemeth MJ, Abrams SI. Regulation of the interferon regulatory factor-8 (IRF-8) tumor suppressor gene by the signal transducer and activator of transcription 5 (STAT5) transcription factor in chronic myeloid leukemia. J Biol Chem 2014; 289:15642-52. [PMID: 24753251 DOI: 10.1074/jbc.m113.544320] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [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: 11/06/2022] Open
Abstract
Tyrosine kinase inhibitors such as imatinib can effectively target the BCR-ABL oncoprotein in a majority of patients with chronic myeloid leukemia (CML). Unfortunately, some patients are resistant primarily to imatinib and others develop drug resistance, prompting interest in the discovery of new drug targets. Although much of this resistance can be explained by the presence of mutations within the tyrosine kinase domain of BCR-ABL, such mutations are not universally identified. Interferon regulatory factor-8 (IRF-8) is a transcription factor that is essential for myelopoiesis. Depressed IRF-8 levels are observed in a majority of CML patients and Irf-8(-/-) mice exhibit a CML-like disease. The underlying mechanisms of IRF-8 loss in CML are unknown. We hypothesized that BCR-ABL suppresses transcription of IRF-8 through STAT5, a proximal BCR-ABL target. Treatment of primary cells from newly diagnosed CML patients in chronic phase as well as BCR-ABL(+) cell lines with imatinib increased IRF-8 transcription. Furthermore, IRF-8 expression in cell line models was necessary for imatinib-induced antitumor responses. We have demonstrated that IRF-8 is a direct target of STAT5 and that silencing of STAT5 induced IRF-8 expression. Conversely, activating STAT5 suppressed IRF-8 transcription. Finally, we showed that STAT5 blockade using a recently discovered antagonist increased IRF-8 expression in patient samples. These data reveal a previously unrecognized BCR-ABL-STAT5-IRF-8 network, which widens the repertoire of potentially new anti-CML targets.
Collapse
Affiliation(s)
| | | | - Elizabeth A Griffiths
- Pharmacology and Therapeutics, and Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263
| | - Michael J Nemeth
- From the Departments of Immunology, Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263
| | | |
Collapse
|
24
|
Li Y, Wei Z, Zhang J, Yang Z, Zhang M. Structural basis of the binding of Merlin FERM domain to the E3 ubiquitin ligase substrate adaptor DCAF1. J Biol Chem 2014; 289:14674-81. [PMID: 24706749 DOI: 10.1074/jbc.m114.551184] [Citation(s) in RCA: 12] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The tumor suppressor gene Nf2 product, Merlin, plays vital roles in controlling proper development of organ sizes by specifically binding to a large number of target proteins localized both in cytoplasm and nuclei. The FERM domain of Merlin is chiefly responsible for its binding to target proteins, although the molecular basis governing these interactions are poorly understood due to lack of structural information. Here, we report the crystal structure of the Merlin FERM domain in complex with its binding domain derived from the E3 ubiquitin ligase substrate adaptor DCAF1 (also known as VPRBP). Unlike target binding modes found in ERM proteins, the Merlin-FERM binding domain of DCAF1 folds as a β-hairpin and binds to the α1/β5-groove of the F3 lobe of Merlin-FERM via extensive hydrophobic interactions. In addition to providing the first structural glimpse of a Merlin-FERM·target complex, the structure of the Merlin·DCAF1 complex is likely to be valuable for understanding the interactions of Merlin with its binding partners other than DCAF1.
Collapse
Affiliation(s)
- Youjun Li
- From the Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Zhiyi Wei
- From the Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China, the Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China, and the Department of Biology, South University of Science and Technology of China, Shenzhen, China
| | - Junyi Zhang
- From the Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Zhou Yang
- From the Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Mingjie Zhang
- From the Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China, the Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China, and
| |
Collapse
|
25
|
Wang Y, Li G, Mao F, Li X, Liu Q, Chen L, Lv L, Wang X, Wu J, Dai W, Wang G, Zhao E, Tang KF, Sun ZS. Ras-induced epigenetic inactivation of the RRAD (Ras-related associated with diabetes) gene promotes glucose uptake in a human ovarian cancer model. J Biol Chem 2014; 289:14225-38. [PMID: 24648519 DOI: 10.1074/jbc.m113.527671] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [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: 01/11/2023] Open
Abstract
RRAD (Ras-related associated with diabetes) is a small Ras-related GTPase that is frequently inactivated by DNA methylation of the CpG island in its promoter region in cancer tissues. However, the role of the methylation-induced RRAD inactivation in tumorigenesis remains unclear. In this study, the Ras-regulated transcriptome and epigenome were profiled by comparing T29H (a Ras(V12)-transformed human ovarian epithelial cell line) with T29 (an immortalized but non-transformed cell line) through reduced representation bisulfite sequencing and digital gene expression. We found that Ras(V12)-mediated oncogenic transformation was accompanied by RRAD promoter hypermethylation and a concomitant loss of RRAD expression. In addition, we found that the RRAD promoter was hypermethylated, and its transcription was reduced in ovarian cancer versus normal ovarian tissues. Treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine resulted in demethylation in the RRAD promoter and restored RRAD expression in T29H cells. Additionally, treatment with farnesyltransferase inhibitor FTI277 resulted in restored RRAD expression and inhibited DNA methytransferase expression and activity in T29H cells. By employing knockdown and overexpression techniques in T29 and T29H, respectively, we found that RRAD inhibited glucose uptake and lactate production by repressing the expression of glucose transporters. Finally, RRAD overexpression in T29H cells inhibited tumor formation in nude mice, suggesting that RRAD is a tumor suppressor gene. Our results indicate that Ras(V12)-mediated oncogenic transformation induces RRAD epigenetic inactivation, which in turn promotes glucose uptake and may contribute to ovarian cancer tumorigenesis.
Collapse
Affiliation(s)
- Yan Wang
- From the Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China, the University of the Chinese Academy of Sciences, Beijing 100080, China
| | - Guiling Li
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China
| | - Fengbiao Mao
- the University of the Chinese Academy of Sciences, Beijing 100080, China, the Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | - Xianfeng Li
- the State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan Province 410078, China, and
| | - Qi Liu
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China
| | - Lin Chen
- the Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China
| | - Lu Lv
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China
| | - Xin Wang
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China
| | - Jinyu Wu
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China
| | - Wei Dai
- From the Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
| | - Guan Wang
- the Department of Obstetrics and Gynecology, General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - Enfeng Zhao
- the Department of Obstetrics and Gynecology, General Hospital of Chinese People's Liberation Army, Beijing 100853, China
| | - Kai-Fu Tang
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China,
| | - Zhong Sheng Sun
- the Institute of Genomic Medicine, Wenzhou Medical University, 268 West Xueyuan Road, Wenzhou, Zhejiang Province 325000, China, the Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing 100101, China,
| |
Collapse
|
26
|
Abstract
Multiple endocrine neoplasia type I (MEN1) is an inherited syndrome that includes susceptibility to pancreatic islet hyperplasia. This syndrome results from mutations in the MEN1 gene, which encodes menin protein. Menin interacts with several transcription factors, including JunD, and inhibits their activities. However, the precise mechanism by which menin suppresses gene expression is not well understood. Here, we show that menin interacts with arsenite-resistant protein 2 (ARS2), a component of the nuclear RNA CAP-binding complex that is crucial for biogenesis of certain miRNAs including let-7a. The levels of primary-let-7a (pri-let-7a) are not affected by menin; however, the levels of mature let-7a are substantially decreased upon Men1 excision. Let-7a targets, including Insr and Irs2, pro-proliferative genes that are crucial for insulin-mediated signaling, are up-regulated in Men1-excised cells. Inhibition of let-7a using anti-miRNA in wild type cells is sufficient to enhance the expression of insulin receptor substrate 2 (IRS2) to levels observed in Men1-excised cells. Depletion of menin does not affect the expression of Drosha and CBP80, but substantially impairs the processing of pri-miRNA to pre-miRNA. Ars2 knockdown decreased let-7a processing in menin-expressing cells but had little impact on let-7a levels in menin-excised cells. As IRS2 is known to mediate insulin signaling and insulin/mitogen-induced cell proliferation, these findings collectively unravel a novel mechanism whereby menin suppresses cell proliferation, at least partly by promoting the processing of certain miRNAs, including let-7a, leading to suppression of Irs2 expression and insulin signaling.
Collapse
Affiliation(s)
- Buddha Gurung
- From the Abramson Family Cancer Research Institute, Department of Cancer Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
| | | | | |
Collapse
|
27
|
Liu Z, Li F, Ruan K, Zhang J, Mei Y, Wu J, Shi Y. Structural and functional insights into the human Börjeson-Forssman-Lehmann syndrome-associated protein PHF6. J Biol Chem 2014; 289:10069-83. [PMID: 24554700 DOI: 10.1074/jbc.m113.535351] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [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: 12/18/2022] Open
Abstract
The plant homeodomain finger 6 (PHF6) was originally identified as the gene mutated in the X-linked mental retardation disorder Börjeson-Forssman-Lehmann syndrome. Mutations in the PHF6 gene have also been associated with T-cell acute lymphoblastic leukemia and acute myeloid leukemia. Approximately half of the disease-associated mutations are distributed in the second conserved extended plant homeodomain (ePHD2) of PHF6, indicating the functional importance of the ePHD2 domain. Here, we report the high resolution crystal structure of the ePHD2 domain of PHF6, which contains an N-terminal pre-PHD (C2HC zinc finger), a long linker, and an atypical PHD finger. PHF6-ePHD2 appears to fold as a novel integrated structural module. Structural analysis of PHF6-ePHD2 reveals pathological implication of PHF6 gene mutations in Börjeson-Forssman-Lehmann syndrome, T-cell acute lymphoblastic leukemia, and acute myeloid leukemia. The binding experiments show that PHF6-ePHD2 can bind dsDNA but not histones. We also demonstrate PHF6 protein directly interacts with the nucleosome remodeling and deacetylation complex component RBBP4. Via this interaction, PHF6 exerts its transcriptional repression activity. Taken together, these data support the hypothesis that PHF6 may function as a transcriptional repressor using its ePHD domains binding to the promoter region of its repressed gene, and this process was regulated by the nucleosome remodeling and deacetylation complex that was recruited to the genomic target site by NoLS region of PHF6.
Collapse
Affiliation(s)
- Zhonghua Liu
- From the Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | | | | | | | | | | | | |
Collapse
|
28
|
Abu-Odeh M, Bar-Mag T, Huang H, Kim T, Salah Z, Abdeen SK, Sudol M, Reichmann D, Sidhu S, Kim PM, Aqeilan RI. Characterizing WW domain interactions of tumor suppressor WWOX reveals its association with multiprotein networks. J Biol Chem 2014; 289:8865-80. [PMID: 24550385 DOI: 10.1074/jbc.m113.506790] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [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: 11/06/2022] Open
Abstract
WW domains are small modules present in regulatory and signaling proteins that mediate specific protein-protein interactions. The WW domain-containing oxidoreductase (WWOX) encodes a 46-kDa tumor suppressor that contains two N-terminal WW domains and a central short-chain dehydrogenase/reductase domain. Based on its ligand recognition motifs, the WW domain family is classified into four groups. The largest one, to which WWOX belongs, recognizes ligands with a PPXY motif. To pursue the functional properties of the WW domains of WWOX, we employed mass spectrometry and phage display experiments to identify putative WWOX-interacting partners. Our analysis revealed that the first WW (WW1) domain of WWOX is the main functional interacting domain. Furthermore, our study uncovered well known and new PPXY-WW1-interacting partners and shed light on novel LPXY-WW1-interacting partners of WWOX. Many of these proteins are components of multiprotein complexes involved in molecular processes, including transcription, RNA processing, tight junction, and metabolism. By utilizing GST pull-down and immunoprecipitation assays, we validated that WWOX is a substrate of the E3 ubiquitin ligase ITCH, which contains two LPXY motifs. We found that ITCH mediates Lys-63-linked polyubiquitination of WWOX, leading to its nuclear localization and increased cell death. Our data suggest that the WW1 domain of WWOX provides a versatile platform that links WWOX with individual proteins associated with physiologically important networks.
Collapse
Affiliation(s)
- Mohammad Abu-Odeh
- From the Lautenberg Center for Immunology and Cancer Research, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel 91120
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Yoo JE, Park YN, Oh BK. PinX1, a telomere repeat-binding factor 1 (TRF1)-interacting protein, maintains telomere integrity by modulating TRF1 homeostasis, the process in which human telomerase reverse Transcriptase (hTERT) plays dual roles. J Biol Chem 2014; 289:6886-6898. [PMID: 24415760 DOI: 10.1074/jbc.m113.506006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [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: 11/06/2022] Open
Abstract
TRF1, a telomere-binding protein, is important for telomere protection and homeostasis. PinX1 interacts with TRF1, but the physiological consequences of their interaction in telomere protection are not yet understood. Here we investigated PinX1 function on TRF1 stability in HeLa cells. PinX1 overexpression stabilized TRF1, but PinX1 depletion by siRNA led to TRF1 degradation, TRF1 ubiquitination, and less TRF1 telomere association. The depletion also induced DNA damage responses at telomeres and chromosome instability. These telomere dysfunctional phenotypes were in fact due to TRF1 deficiency. We also report that hTERT, a catalytic component of telomerase, plays dual roles in the TRF1 steady state pathway. PinX1-mediated TRF1 stability was not observed in hTERT-negative immortal cells, but was pronounced when hTERT was ectopically expressed in the cells, suggesting that hTERT may be needed in the PinX1-mediated TRF1 stability pathway. Interestingly, the knockdown of both PinX1 and hTERT in HeLa cells stabilized TRF1, suppressed DNA damage response activation, and restored chromosome stability. In summary, our findings suggested that PinX1 may maintain telomere integrity by regulating TRF1 stability and that hTERT may act as both a positive and a negative regulator of TRF1 homeostasis in a PinX1-dependent manner.
Collapse
Affiliation(s)
- Jeong Eun Yoo
- Department of Pathology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, 250 Seongsan-ro, Seodaemoon-gu, Seoul 120-752, Korea
| | - Young Nyun Park
- Department of Pathology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, 250 Seongsan-ro, Seodaemoon-gu, Seoul 120-752, Korea; Severance Biomedical Science Institute, Yonsei University College of Medicine, 250 Seongsan-ro, Seodaemoon-gu, Seoul 120-752, Korea.
| | - Bong-Kyeong Oh
- Department of Obstetrics and Gynecology, Institute of Medical Science, Hanyang University College of Medicine, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea.
| |
Collapse
|
30
|
Abstract
Retinoblastoma-binding protein 1 (RBBP1) is a tumor and leukemia suppressor that binds both methylated histone tails and DNA. Our previous studies indicated that RBBP1 possesses a Tudor domain, which cannot bind histone marks. In order to clarify the function of the Tudor domain, the solution structure of the RBBP1 Tudor domain was determined by NMR and is presented here. Although the proteins are unrelated, the RBBP1 Tudor domain forms an interdigitated double Tudor structure similar to the Tudor domain of JMJD2A, which is an epigenetic mark reader. This indicates the functional diversity of Tudor domains. The RBBP1 Tudor domain structure has a significant area of positively charged surface, which reveals a capability of the RBBP1 Tudor domain to bind nucleic acids. NMR titration and isothermal titration calorimetry experiments indicate that the RBBP1 Tudor domain binds both double- and single-stranded DNA with an affinity of 10-100 μM; no apparent DNA sequence specificity was detected. The DNA binding mode and key interaction residues were analyzed in detail based on a model structure of the Tudor domain-dsDNA complex, built by HADDOCK docking using the NMR data. Electrostatic interactions mediate the binding of the Tudor domain with DNA, which is consistent with NMR experiments performed at high salt concentration. The DNA-binding residues are conserved in Tudor domains of the RBBP1 protein family, resulting in conservation of the DNA-binding function in the RBBP1 Tudor domains. Our results provide further insights into the structure and function of RBBP1.
Collapse
Affiliation(s)
- Weibin Gong
- From the National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China and
| | | | | | | |
Collapse
|
31
|
Ableser MJ, Penuela S, Lee J, Shao Q, Laird DW. Connexin43 reduces melanoma growth within a keratinocyte microenvironment and during tumorigenesis in vivo. J Biol Chem 2013; 289:1592-603. [PMID: 24297173 DOI: 10.1074/jbc.m113.507228] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [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: 12/22/2022] Open
Abstract
Connexins (Cx) have been identified as tumor suppressors or enhancers, a distinction that appears to be dependent on the type and stage of disease. However, the role of connexins in melanoma tumorigenesis and their status during cancer onset and progression remain controversial and unclear. Here, we show that the aggressive B16-BL6 mouse melanoma cell line expresses low basal levels of Cx26 and Cx43, rendering them gap junctional intercellular communication-deficient as elucidated by immunofluorescence, Western blotting, and dye transfer studies. Following ectopic expression of green fluorescent protein-tagged Cx26 and Cx43 in these connexin-deficient melanomas, punctate gap junction-like plaques were evident at sites of cell-cell apposition, and the incidence of dye transfer was significantly increased similar to connexin-rich keratinocytes. We found that the expression of Cx43, but not Cx26, significantly reduced cellular proliferation and anchorage-independent growth from control melanomas, whereas migration was unaffected. Additionally, melanomas expressing Cx43 displayed significantly reduced growth within the in situ-like microenvironment of keratinocytes, despite a lack of heterocellular gap junctional intercellular communication between the two cell types. Furthermore, when grown in vivo in the chicken chorioallantoic membrane, primary tumors derived from Cx43-expressing melanomas were significantly smaller than controls, whereas Cx26-expressing melanomas produced tumors similar to controls. Collectively, these results suggest that Cx43, and not Cx26, can act as a tumor suppressor during melanoma tumorigenesis.
Collapse
|
32
|
Rather MI, Swamy S, Gopinath KS, Kumar A. Transcriptional repression of tumor suppressor CDC73, encoding an RNA polymerase II interactor, by Wilms tumor 1 protein (WT1) promotes cell proliferation: implication for cancer therapeutics. J Biol Chem 2013; 289:968-76. [PMID: 24257751 DOI: 10.1074/jbc.m113.483255] [Citation(s) in RCA: 22] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The Wilms tumor 1 gene (WT1) can either repress or induce the expression of genes. Inconsistent with its tumor suppressor role, elevated WT1 levels have been observed in leukemia and solid tumors. WT1 has also been suggested to act as an oncogene by inducing the expression of MYC and BCL-2. However, these are only the correlational studies, and no functional study has been performed to date. Consistent with its tumor suppressor role, CDC73 binds to RNA polymerase II as part of a PAF1 transcriptional regulatory complex and causes transcriptional repression of oncogenes MYC and CCND1. It also represses β-catenin-mediated transcription. Based on the reduced level of CDC73 in oral squamous cell carcinoma (OSCC) samples in the absence of loss-of-heterozygosity, promoter methylation, and mutations, we speculated that an inhibitory transcription factor is regulating its expression. The bioinformatics analysis predicted WT1 as an inhibitory transcription factor to regulate the CDC73 level. Our results showed that overexpression of WT1 decreased CDC73 levels and promoted proliferation of OSCC cells. ChIP and EMSA results demonstrated binding of WT1 to the CDC73 promoter. The 5-azacytidine treatment of OSCC cells led to an up-regulation of WT1 with a concomitant down-regulation of CDC73, further suggesting regulation of CDC73 by WT1. Exogenous CDC73 attenuated the protumorigenic activity of WT1 by apoptosis induction. An inverse correlation between expression levels of CDC73 and WT1 was observed in OSCC samples. These observations indicated that WT1 functions as an oncogene by repressing the expression of CDC73 in OSCC. We suggest that targeting WT1 could be a therapeutic strategy for cancer, including OSCC.
Collapse
Affiliation(s)
- Mohammad Iqbal Rather
- From the Department of Molecular Reproduction, Development, and Genetics, Indian Institute of Science, Bangalore 560012, India and
| | | | | | | |
Collapse
|
33
|
Gangula NR, Maddika S. WD repeat protein WDR48 in complex with deubiquitinase USP12 suppresses Akt-dependent cell survival signaling by stabilizing PH domain leucine-rich repeat protein phosphatase 1 (PHLPP1). J Biol Chem 2013; 288:34545-54. [PMID: 24145035 PMCID: PMC3843068 DOI: 10.1074/jbc.m113.503383] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [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: 11/23/2022] Open
Abstract
PHLPP1 (PH domain leucine-rich repeat protein phosphatase 1) is a protein-serine/threonine phosphatase and a negative regulator of the PI3-kinase/Akt pathway. Although its function as a suppressor of tumor cell growth has been established, the mechanism of its regulation is not completely understood. In this study, by utilizing the tandem affinity purification approach we have identified WDR48 and USP12 as novel PHLPP1-associated proteins. The WDR48·USP12 complex deubiquitinates PHLPP1 and thereby enhances its protein stability. Similar to PHLPP1 function, WDR48 and USP12 negatively regulate Akt activation and thus promote cellular apoptosis. Functionally, we show that WDR48 and USP12 suppress proliferation of tumor cells. Importantly, we found a WDR48 somatic mutation (L580F) that is defective in stabilizing PHLPP1 in colorectal cancers, supporting a WDR48 role in tumor suppression. Together, our results reveal WDR48 and USP12 as novel PHLPP1 regulators and potential suppressors of tumor cell survival.
Collapse
Affiliation(s)
- Narmadha Reddy Gangula
- From the Laboratory of Cell Death and Cell Survival, Centre for DNA Fingerprinting and Diagnostics (CDFD), Nampally, Hyderabad 500001, India
| | | |
Collapse
|
34
|
Peng M, Zhang H, Jaafar L, Risinger JI, Huang S, Mivechi NF, Ko L. Human ovarian cancer stroma contains luteinized theca cells harboring tumor suppressor gene GT198 mutations. J Biol Chem 2013; 288:33387-97. [PMID: 24097974 DOI: 10.1074/jbc.m113.485581] [Citation(s) in RCA: 13] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ovarian cancer is a highly lethal gynecological cancer, and its causes remain to be understood. Using a recently identified tumor suppressor gene, GT198 (PSMC3IP), as a unique marker, we searched for the identity of GT198 mutant cells in ovarian cancer. GT198 has germ line mutations in familial and early onset breast and ovarian cancers and recurrent somatic mutations in sporadic fallopian tube cancers. GT198 protein has been shown as a steroid hormone receptor coregulator and also as a crucial factor in DNA repair. In this study, using GT198 as a marker for microdissection, we find that ovarian tumor stromal cells harboring GT198 mutations are present in various types of ovarian cancer including high and low grade serous, endometrioid, mucinous, clear cell, and granulosa cell carcinomas and in precursor lesions such as inclusion cysts. The mutant stromal cells consist of a luteinized theca cell lineage at various differentiation stages including CD133(+), CD44(+), and CD34(+) cells, although the vast majority of them are differentiated overexpressing steroidogenic enzyme CYP17, a theca cell-specific marker. In addition, wild type GT198 suppresses whereas mutant GT198 protein stimulates CYP17 expression. The chromatin-bound GT198 on the human CYP17 promoter is decreased by overexpressing mutant GT198 protein, implicating the loss of wild type suppression in mutant cells. Together, our results suggest that GT198 mutant luteinized theca cells overexpressing CYP17 are common in ovarian cancer stroma. Because first hit cancer gene mutations would specifically mark cancer-inducing cells, the identification of mutant luteinized theca cells may add crucial evidence in understanding the cause of human ovarian cancer.
Collapse
|
35
|
Iwasa H, Kudo T, Maimaiti S, Ikeda M, Maruyama J, Nakagawa K, Hata Y. The RASSF6 tumor suppressor protein regulates apoptosis and the cell cycle via MDM2 protein and p53 protein. J Biol Chem 2013; 288:30320-30329. [PMID: 24003224 DOI: 10.1074/jbc.m113.507384] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [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: 12/31/2022] Open
Abstract
Ras association domain family (RASSF) 6 is a member of the C-terminal RASSF proteins such as RASSF1A and RASSF3. RASSF6 is involved in apoptosis in various cells under miscellaneous conditions, but it remains to be clarified how RASSF6 exerts tumor-suppressive roles. We reported previously that RASSF3 facilitates the degradation of MDM2, a major E3 ligase of p53, and stabilizes p53 to function as a tumor suppressor. In this study, we demonstrate that RASSF6 overexpression induces G1/S arrest in p53-positive cells. Its depletion prevents UV- and VP-16-induced apoptosis and G1/S arrest in HCT116 and U2OS cells. RASSF6-induced apoptosis partially depends on p53. RASSF6 binds MDM2 and facilitates its ubiquitination. RASSF6 depletion blocks the increase of p53 in response to UV exposure and up-regulation of p53 target genes. RASSF6 depletion delays DNA repair in UV- and VP-16-treated cells and increases polyploid cells after VP-16 treatment. These findings indicate that RASSF6 stabilizes p53, regulates apoptosis and the cell cycle, and functions as a tumor suppressor. Together with the previous reports regarding RASSF1A and RASSF3, the stabilization of p53 may be the common function of the C-terminal RASSF proteins.
Collapse
Affiliation(s)
| | - Takumi Kudo
- From the Department of Medical Biochemistry and; Department of Neurosurgery, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519, Japan and
| | - Sainawaer Maimaiti
- From the Department of Medical Biochemistry and; the Department of Psychotherapy, The Fourth People's Hospital of Urumqi, Urumqi 830000, China
| | | | | | | | - Yutaka Hata
- From the Department of Medical Biochemistry and.
| |
Collapse
|
36
|
Tanaka K, Kondo K, Kitajima K, Muraoka M, Nozawa A, Hara T. Tumor-suppressive function of protein-tyrosine phosphatase non-receptor type 23 in testicular germ cell tumors is lost upon overexpression of miR142-3p microRNA. J Biol Chem 2013; 288:23990-9. [PMID: 23843459 DOI: 10.1074/jbc.m113.478891] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [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: 01/04/2023] Open
Abstract
Protein-tyrosine phosphatase non-receptor type 23 (PTPN23) is a candidate tumor suppressor involved in the tumorigenesis of various organs. However, its physiological role(s) and detailed expression profile(s) have not yet been elucidated. We investigated the function and regulation of PTPN23 in the formation of testicular germ cell tumors (TGCTs). Expression of PTPN23 in human TGCT cell lines was significantly lower than that in spermatogonial stem cells in mice. Overexpression of PTPN23 in NEC8, a human TGCT cell line, suppressed soft agar colony formation in vitro and tumor formation in nude mice in vivo. These data indicate that PTPN23 functions as a tumor suppressor in TGCTs. Multiple computational algorithms predicted that the 3' UTR of human PTPN23 is a target for miR-142-3p. A luciferase reporter assay confirmed that miR-142-3p bound directly to the 3' UTR of PTPN23. Introduction of pre-miR-142 in the PTPN23 transfectant of NEC8 led to suppressed expression of PTPN23 and increased soft agar colony formation. Quantitative RT-PCR data revealed a significantly higher expression of miR-142-3p in human seminomas compared with normal testes. No difference in mRNA expression between seminoma and non-seminoma samples was detected by in situ hybridization. Both quantitative RT-PCR and immunohistochemical analyses revealed that PTPN23 expression was significantly lower in TGCTs than in normal testicular tissues. Finally, a lack of PTPN23 protein expression in human TGCTs correlated with a relatively higher miR-142-3p expression. These data suggest that PTPN23 is a tumor suppressor and that repression of PTPN23 expression by miR-142-3p plays an important role in the pathogenesis of TGCTs.
Collapse
Affiliation(s)
- Kiyoko Tanaka
- Stem Cell Project Group, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
| | | | | | | | | | | |
Collapse
|
37
|
Dai C, Shi D, Gu W. Negative regulation of the acetyltransferase TIP60-p53 interplay by UHRF1 (ubiquitin-like with PHD and RING finger domains 1). J Biol Chem 2013; 288:19581-92. [PMID: 23677994 PMCID: PMC3707659 DOI: 10.1074/jbc.m113.476606] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 05/14/2013] [Indexed: 11/06/2022] Open
Abstract
Numerous studies indicate the importance of acetylation in p53-mediated stress responses upon DNA damage. We and others previously showed that TIP60 (Tat-interacting protein of 60 kDa)-mediated acetylation of p53 at K120 is crucial for p53-dependent apoptotic responses. Nevertheless, it remains unclear how TIP60-mediated effects on p53 are dynamically regulated in vivo. Here, we report that UHRF1 (ubiquitin-like with PHD and RING finger domains 1) interacts with TIP60 both in vitro and in vivo and induces degradation-independent ubiquitination of TIP60. Moreover, UHRF1 expression markedly suppresses the ability of TIP60 to acetylate p53. In contrast, RNAi-mediated knockdown of UHRF1 increases the endogenous levels of p53 acetylation at K120 and p53-mediated apoptosis is significantly enhanced in UHRF1-depleted cells. To elucidate the mechanisms of this regulation, we found that the interaction between TIP60 and p53 is severely inhibited in the presence of UHRF1, suggesting that UHRF1 modulates TIP60-mediated functions in both K120 acetylation-dependent and -independent manners. Consistent with this notion, UHRF1 knockdown promotes activation of p21 and PUMA but not MDM2. These findings demonstrate that UHRF1 is a critical negative regulator of TIP60 and suggest that UHRF1-mediated effects on p53 may contribute, at least in part, to its role in tumorigenesis.
Collapse
Affiliation(s)
- Chao Dai
- From the Institute for Cancer Genetics
- Herbert Irving Comprehensive Cancer Center, and
- Department of Biological Sciences, Columbia University, New York, New York 10032
| | - Dingding Shi
- From the Institute for Cancer Genetics
- Herbert Irving Comprehensive Cancer Center, and
| | - Wei Gu
- From the Institute for Cancer Genetics
- Department of Pathology and Cell Biology
- Herbert Irving Comprehensive Cancer Center, and
| |
Collapse
|
38
|
Rafidi H, Mercado F, Astudillo M, Fry WHD, Saldana M, Carraway KL, Sweeney C. Leucine-rich repeat and immunoglobulin domain-containing protein-1 (Lrig1) negative regulatory action toward ErbB receptor tyrosine kinases is opposed by leucine-rich repeat and immunoglobulin domain-containing protein 3 (Lrig3). J Biol Chem 2013; 288:21593-605. [PMID: 23723069 DOI: 10.1074/jbc.m113.486050] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [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] Open
Abstract
Lrig1 is the founding member of the Lrig family of transmembrane leucine-rich repeat proteins, which also includes Lrig2 and Lrig3. Lrig1 is a negative regulator of oncogenic receptor tyrosine kinases, including ErbB and Met receptors, and promotes receptor degradation. Lrig1 has recently emerged as both a tumor suppressor and a key regulator of epidermal and epithelial stem cell quiescence. Despite this, little is known of the mechanisms by which Lrig1 is regulated. Lrig3 was recently reported to increase ErbB receptor expression suggesting that it may function in a manner opposite to Lrig1. In this study, we explore the interaction between Lrig1 and Lrig3 and demonstrate that Lrig1 and Lrig3 functionally oppose one another. Lrig3 opposes Lrig1 negative regulatory activity and stabilizes ErbB receptors. Conversely, Lrig1 destabilizes Lrig3, limiting Lrig3's positive effects on receptors and identifying Lrig3 as a new target of Lrig1. These studies provide new insight into the regulation of Lrig1 and uncover a complex cross-talk between Lrig1 and Lrig3.
Collapse
Affiliation(s)
- Hanine Rafidi
- Department of Biochemistry and Molecular Medicine, University of California at Davis Comprehensive Cancer Center, Sacramento, California 95817, USA
| | | | | | | | | | | | | |
Collapse
|
39
|
van der Deen M, Taipaleenmäki H, Zhang Y, Teplyuk NM, Gupta A, Cinghu S, Shogren K, Maran A, Yaszemski MJ, Ling L, Cool SM, Leong DT, Dierkes C, Zustin J, Salto-Tellez M, Ito Y, Bae SC, Zielenska M, Squire JA, Lian JB, Stein JL, Zambetti GP, Jones SN, Galindo M, Hesse E, Stein GS, van Wijnen AJ. MicroRNA-34c inversely couples the biological functions of the runt-related transcription factor RUNX2 and the tumor suppressor p53 in osteosarcoma. J Biol Chem 2013; 288:21307-21319. [PMID: 23720736 DOI: 10.1074/jbc.m112.445890] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [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: 12/15/2022] Open
Abstract
Osteosarcoma (OS) is a primary bone tumor that is most prevalent during adolescence. RUNX2, which stimulates differentiation and suppresses proliferation of osteoblasts, is deregulated in OS. Here, we define pathological roles of RUNX2 in the etiology of OS and mechanisms by which RUNX2 expression is stimulated. RUNX2 is often highly expressed in human OS biopsies and cell lines. Small interference RNA-mediated depletion of RUNX2 inhibits growth of U2OS OS cells. RUNX2 levels are inversely linked to loss of p53 (which predisposes to OS) in distinct OS cell lines and osteoblasts. RUNX2 protein levels decrease upon stabilization of p53 with the MDM2 inhibitor Nutlin-3. Elevated RUNX2 protein expression is post-transcriptionally regulated and directly linked to diminished expression of several validated RUNX2 targeting microRNAs in human OS cells compared with mesenchymal progenitor cells. The p53-dependent miR-34c is the most significantly down-regulated RUNX2 targeting microRNAs in OS. Exogenous supplementation of miR-34c markedly decreases RUNX2 protein levels, whereas 3'-UTR reporter assays establish RUNX2 as a direct target of miR-34c in OS cells. Importantly, Nutlin-3-mediated stabilization of p53 increases expression of miR-34c and decreases RUNX2. Thus, a novel p53-miR-34c-RUNX2 network controls cell growth of osseous cells and is compromised in OS.
Collapse
Affiliation(s)
- Margaretha van der Deen
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106
| | - Hanna Taipaleenmäki
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106,; Heisenberg-Group for Molecular Skeletal Biology, Department of Trauma, Hand, and Reconstructive Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Ying Zhang
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106
| | - Nadiya M Teplyuk
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106
| | - Anurag Gupta
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106
| | - Senthilkumar Cinghu
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106
| | - Kristen Shogren
- Departments of Orthopedic Surgery and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - Avudaiappan Maran
- Departments of Orthopedic Surgery and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - Michael J Yaszemski
- Departments of Orthopedic Surgery and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905
| | - Ling Ling
- Institute of Medical Biology, Agency for Science, Technology, and Research, 8A Biomedical Grove, #06-06, Immunos, Singapore 138648
| | - Simon M Cool
- Institute of Medical Biology, Agency for Science, Technology, and Research, 8A Biomedical Grove, #06-06, Immunos, Singapore 138648,; Department of Orthopaedic Surgery, National University Hospital of Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 11, Singapore 119228
| | - David T Leong
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117576
| | - Christian Dierkes
- Medical Care Unit for Histology, Cytology, and Molecular Diagnostics, 54296 Trier, Germany
| | - Jozef Zustin
- Department of Pathology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Manuel Salto-Tellez
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom,; Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, 12-01, Centre for Translational Medicine, Singapore 117599
| | - Yoshiaki Ito
- Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, 12-01, Centre for Translational Medicine, Singapore 117599
| | - Suk-Chul Bae
- Department of Biochemistry, School of Medicine, Chungbuk National University, Cheongju 361-763, South Korea
| | - Maria Zielenska
- Department of Paediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Jeremy A Squire
- Department of Pathology and Molecular Medicine, Kingston General Hospital, Queen's University, Kingston, Ontario K7L 3N6 Canada
| | - Jane B Lian
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106,; Department of Biochemistry, HSRF 326, Vermont Cancer Center for Basic and Translational Research, University of Vermont Medical School, Burlington, Vermont 05405
| | - Janet L Stein
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106,; Department of Biochemistry, HSRF 326, Vermont Cancer Center for Basic and Translational Research, University of Vermont Medical School, Burlington, Vermont 05405
| | - Gerard P Zambetti
- Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, and
| | - Stephen N Jones
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106
| | - Mario Galindo
- Millennium Institute on Immunology and Immunotherapy and Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Eric Hesse
- Heisenberg-Group for Molecular Skeletal Biology, Department of Trauma, Hand, and Reconstructive Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Gary S Stein
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106,; Department of Biochemistry, HSRF 326, Vermont Cancer Center for Basic and Translational Research, University of Vermont Medical School, Burlington, Vermont 05405,.
| | - Andre J van Wijnen
- From the Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0106,; Departments of Orthopedic Surgery and Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905,; Institute of Medical Biology, Agency for Science, Technology, and Research, 8A Biomedical Grove, #06-06, Immunos, Singapore 138648,; Department of Orthopaedic Surgery, National University Hospital of Singapore, 1E Kent Ridge Road, NUHS Tower Block Level 11, Singapore 119228,.
| |
Collapse
|
40
|
Jacobi CLJ, Rudigier LJ, Scholz H, Kirschner KM. Transcriptional regulation by the Wilms tumor protein, Wt1, suggests a role of the metalloproteinase Adamts16 in murine genitourinary development. J Biol Chem 2013; 288:18811-24. [PMID: 23661704 DOI: 10.1074/jbc.m113.464644] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [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: 11/06/2022] Open
Abstract
ADAMTS16 (a disintegrin and metalloproteinase with thrombospondin motifs) is a secreted mammalian metalloproteinase with unknown function. We report here that murine Adamts16 is co-expressed with the Wilms tumor protein, Wt1, in the developing glomeruli of embryonic kidneys. Adamts16 mRNA levels were significantly reduced upon transfection of embryonic murine kidney explants with Wt1 antisense vivo-morpholinos. Antisense knockdown of Adamts16 inhibited branching morphogenesis in kidney organ cultures. Adamts16 was detected by in situ mRNA hybridization and/or immunohistochemistry also in embryonic gonads and in spermatids and granulosa cells of adult testes and ovaries, respectively. Silencing of Wt1 by transfection with antisense vivo-morpholinos significantly increased Adamts16 mRNA in cultured embryonic XY gonads (11.5 and 12.5 days postconception), and reduced Adamts16 transcripts in XX gonads (12.5 and 13.5 days postconception). Three predicted Wt1 consensus motifs could be identified in the promoter and the 5'-untranslated region of the murine Adamts16 gene. Binding of Wt1 protein to these elements was verified by EMSA and ChIP. A firefly luciferase reporter gene under control of the Adamts16 promoter was activated ∼8-fold by transient co-transfection of human granulosa cells with a Wt1 expression construct. Gradual shortening of the 5'-flanking sequence successively reduced and eventually abrogated Adamts16 promoter activation by Wt1. These findings demonstrate that Wt1 differentially regulates the Adamts16 gene in XX and XY embryonic gonads. It is suggested that Adamts16 acts immediately downstream of Wt1 during murine urogenital development. We propose that Adamts16 is involved in branching morphogenesis of the kidneys in mice.
Collapse
Affiliation(s)
- Charlotte L J Jacobi
- Institut für Vegetative Physiologie, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | | | | | | |
Collapse
|
41
|
Wang Y, Jiang L, Ji X, Yang B, Zhang Y, Fu XD. Hepatitis B viral RNA directly mediates down-regulation of the tumor suppressor microRNA miR-15a/miR-16-1 in hepatocytes. J Biol Chem 2013; 288:18484-93. [PMID: 23649629 DOI: 10.1074/jbc.m113.458158] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [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: 12/17/2022] Open
Abstract
Hepatitis B virus (HBV) is a key risk factor for the development of hepatocellular carcinoma (HCC). Recent work suggests a functional link between HCC and microRNA expression, but the mechanism underlying the functional interaction between microRNA and HBV infection has remained largely elusive. Here we present evidence that the microRNA machinery serves as a defense system against HBV infection, which, in turn, reprograms the expression of specific microRNAs. We demonstrate a critical role of miR-15a/miR-16-1 in this functional interplay between microRNA and HBV infection, but in contrast to various indirect mechanisms mediated by viral proteins, we unexpectedly found that the HBx transcript directly triggers the down-regulation of miR-15a/miR-16-1 via the microRNA targeting sequences in the viral RNA. Because miR-15a and miR-16-1 are well known tumor suppressor microRNAs in multiple human cancers, our findings raise the intriguing possibility that viral RNA-mediated down-regulation of specific tumor suppressor microRNAs may contribute to HCC development in HBV-infected cells.
Collapse
Affiliation(s)
- Yanling Wang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, Hubei 430072, China
| | | | | | | | | | | |
Collapse
|
42
|
Odell AF, Odell LR, Askham JM, Alogheli H, Ponnambalam S, Hollstein M. A novel p53 mutant found in iatrogenic urothelial cancers is dysfunctional and can be rescued by a second-site global suppressor mutation. J Biol Chem 2013; 288:16704-16714. [PMID: 23612969 DOI: 10.1074/jbc.m112.443168] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [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: 11/06/2022] Open
Abstract
Exposure to herbal remedies containing the carcinogen aristolochic acid (AA) has been widespread in some regions of the world. Rare A→T TP53 mutations were recently discovered in AA-associated urothelial cancers. The near absence of these mutations among all other sequenced human tumors suggests that they could be biologically silent. There are no cell banks with established lines derived from human tumors with which to explore the influence of the novel mutants on p53 function and cellular behavior. To investigate their impact, we generated isogenic mutant clones by integrase-mediated cassette exchange at the p53 locus of platform (null) murine embryonic fibroblasts and kidney epithelial cells. Common tumor mutants (R248W, R273C) were compared with the AA-associated mutants N131Y, R249W, and Q104L. Assays of cell proliferation, migration, growth in soft agar, apoptosis, senescence, and gene expression revealed contrasting outcomes on cellular behavior following introduction of N131Y or Q104L. The N131Y mutant demonstrated a phenotype akin to common tumor mutants, whereas Q104L clone behavior resembled that of cells with wild-type p53. Wild-type p53 responses were restored in double-mutant cells harboring N131Y and N239Y, a second-site rescue mutation, suggesting that pharmaceutical reactivation of p53 function in tumors expressing N131Y could have therapeutic benefit. N131Y is likely to contribute directly to tumor phenotype and is a promising candidate biomarker of AA exposure and disease. Rare mutations thus do not necessarily point to sites where amino acid exchanges are phenotypically neutral. Encounter with mutagenic insults targeting cryptic sites can reveal specific signature hotspots.
Collapse
Affiliation(s)
- Adam F Odell
- Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, United Kingdom.
| | - Luke R Odell
- Division of Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, 75123 Uppsala, Sweden
| | - Jon M Askham
- Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Hiba Alogheli
- Division of Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, Uppsala University, 75123 Uppsala, Sweden
| | - Sreenivasan Ponnambalam
- School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Monica Hollstein
- Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, United Kingdom; Department C016, German Cancer Research Centre, 69120 Heidelberg, Germany.
| |
Collapse
|
43
|
Qi W, Fitchev PS, Cornwell ML, Greenberg J, Cabe M, Weber CR, Roy HK, Crawford SE, Savkovic SD. FOXO3 growth inhibition of colonic cells is dependent on intraepithelial lipid droplet density. J Biol Chem 2013; 288:16274-16281. [PMID: 23603907 DOI: 10.1074/jbc.m113.470617] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [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: 11/06/2022] Open
Abstract
Forkhead transcription factor FOXO3 plays a critical role in suppressing tumor growth, in part, by increasing the cell cycle inhibitor p27kip1, and Foxo3 deficiency in mice results in marked colonic epithelial proliferation. Here, we show in Foxo3-deficient colonic epithelial cells a striking increase in intracytoplasmic lipid droplets (LDs), a dynamic organelle recently observed in human tumor tissue. Although the regulation and function of LDs in non-adipocytes is unclear, we hypothesize that the anti-proliferative effect of FOXO3 was dependent on lowering LD density, thus decreasing fuel energy in both normal and colon cancer cells. In mouse colonic tumors, we found an increased expression of LD coat protein PLIN2 compared with normal colonic epithelial cells. Stimulation of LD density in human colon cancer cells led to a PI3K-dependent loss of FOXO3 and a decrease in the negative regulator of lipid metabolism in Sirtuin6 (SIRT6). Foxo3 deficiency also led to a decrease in SIRT6, revealing the existence of LD and FOXO3 feedback regulation in colonic cells. In parallel, LD-dependent loss of FOXO3 led to its dissociation from the promoter and decreased expression of the cell cycle inhibitor p27kip1. Stimulation of LD density promoted proliferation in colon cancer cells, whereas silencing PLIN2 or overexpression of FOXO3 inhibited proliferation. Taken together, FOXO3 and LDs might serve as new targets for therapeutic intervention of colon cancer.
Collapse
Affiliation(s)
- Wentao Qi
- Department of Medicine, Division of Gastroenterology, Northshore University HealthSystem Research Institute, Evanston, Illinois 60201
| | - Philip S Fitchev
- Department of Pathology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
| | - Mona L Cornwell
- Department of Pathology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
| | - Jordan Greenberg
- Department of Medicine, Division of Gastroenterology, Northshore University HealthSystem Research Institute, Evanston, Illinois 60201
| | - Maleen Cabe
- Department of Medicine, Division of Gastroenterology, Northshore University HealthSystem Research Institute, Evanston, Illinois 60201
| | | | - Hemant K Roy
- Department of Medicine, Division of Gastroenterology, Northshore University HealthSystem Research Institute, Evanston, Illinois 60201
| | - Susan E Crawford
- Department of Pathology, Saint Louis University School of Medicine, St. Louis, Missouri 63104
| | - Suzana D Savkovic
- Department of Medicine, Division of Gastroenterology, Northshore University HealthSystem Research Institute, Evanston, Illinois 60201.
| |
Collapse
|
44
|
Chen Z, Sun X, Shen S, Zhang H, Ma X, Liu J, Kuang S, Yu Q. Wedelolactone, a naturally occurring coumestan, enhances interferon-γ signaling through inhibiting STAT1 protein dephosphorylation. J Biol Chem 2013; 288:14417-14427. [PMID: 23580655 DOI: 10.1074/jbc.m112.442970] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [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: 11/06/2022] Open
Abstract
Signal transducers and activators of transcription 1 (STAT1) transduces signals from cytokines and growth factors, particularly IFN-γ, and regulates expression of genes involved in cell survival/death, proliferation, and migration. STAT1 is activated through phosphorylation on its tyrosine 701 by JAKs and is inactivated through dephosphorylation by tyrosine phosphatases. We discovered a natural compound, wedelolactone, that increased IFN-γ signaling by inhibiting STAT1 dephosphorylation and prolonging STAT1 activation through specific inhibition of T-cell protein tyrosine phosphatase (TCPTP), an important tyrosine phosphatase for STAT1 dephosphorylation. More interestingly, wedelolactone inhibited TCPTP through interaction with the C-terminal autoinhibition domain of TCPTP. We also found that wedelolactone synergized with IFN-γ to induce apoptosis of tumor cells. Our data suggest a new target for anticancer or antiproliferation drugs, a new mechanism to regulate PTPs specifically, and a new drug candidate for treating cancer or other proliferation disorders.
Collapse
Affiliation(s)
- Zhimin Chen
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Xiaoxiao Sun
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Shensi Shen
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Haohao Zhang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Xiuquan Ma
- Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Jingli Liu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Shan Kuang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China
| | - Qiang Yu
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 201203 Shanghai, China.
| |
Collapse
|