TET enzymes and 5hmC epigenetic mark: new key players in carcinogenesis and progression in gynecological cancers

DNA methylation is an epigenetic mechanism involving the transfer of a methyl group onto the C5 position of the cytosine to form 5-methylcytosine (5mC). In general, DNA methylation in cancer is associated with the repression of the expression of tumor suppressor genes (TSG) and the demethylation with the overexpression of oncogenes. DNA methylation was considered a stable modification for a long time, but in 2009, it was reported that DNA methylation is a dynamic modification. The Ten-Eleven-Translocations (TET) enzymes include TET1, TET2, and TET3 and participate in DNA demethylation through the oxidation of 5mC to 5-hydroxymethylcytosine (5hmC). The 5hmC oxidates to 5-formylcytosine (5fC) and 5-carboxylcitosine (5caC), which are replaced by unmodified cytosines via Thymine-DNA Glycosylase (TDG). Several studies have shown that the expression of TET proteins and 5hmC levels are deregulated in gynecological cancers, such as cervical (CC), endometrial (EC), and ovarian (OC) cancers. In addition, the molecular mechanisms involved in this deregulation have been reported, as well as their potential role as biomarkers in these types of cancers. This review shows the state-of-art TET enzymes and the 5hmC epigenetic mark in CC, EC, and OC.

EMMPRIN is an emerging protein capable of regulating cancer hallmarks

EMMPRIN, also known as Basigin or CD147, is a transmembrane glycoprotein member of the immunoglobulin superfamily. It is expressed basally in cells that regulate physiological processes of the cardiovascular, nervous, and immune systems. However, EMMPRIN is also capable of interacting with different proteins, like VEGFR, SMAD4, Integrin, MCT, CyPA, GLUT1, CAIV, Annexin II, Cav-1, CAML, etc., and regulating signaling pathways that stimulate the cell processes of proliferation, apoptosis, metabolism, adhesion, invasion, migration, metastasis, tumor immune response, and angiogenesis processes, which favors the development of different types of cancer. EMMPRIN is the first protein reported that favors cancer development due to its ability to interact with extracellular, intracellular, and membrane proteins. In conclusion, EMMPRIN regulates several proteins associated with the development of tumor processes. Therefore, blocking the expression of EMMPRIN can be a therapeutic target, and the analysis of its expression can be used as an important biomarker in cancer.

Use of coumarins as complementary medicine with an integrative approach against cervical cancer: background and mechanisms of action

Cervical cancer is characterized by the cellular transformation caused by Human Papillomavirus (HPV), favoring cell proliferation, migration, invasion, and metastasis. Cervical cancer is conventionally treated with radiation therapy, and chemotherapy focused on the destruction of tumor cells. However, chemoresistance and low selectivity between tumor and non-tumor cells have been reported, causing side effects in patients. Metabolites of natural origin have shown selectivity against tumor cells, suggesting their use for reducing the side effects caused by drugs used in conventional therapy. Among these compounds, several natural coumarins stand out, such as auraptene, scopoletin, osthole, and praeruptorin, of which antiproliferative, anti-migratory, and anti-invasive activity have been reported. Auraptene, scopoletin, osthole, and praeruptorin show a cytotoxic or antiproliferative effect on cervical tumor cells, arresting the cell cycle by inducing the overexpression of negative regulators of the cell cycle, or inducing cell death by increasing the expression of pro-apoptotic proteins and decreasing that of anti-apoptotic proteins. On the other hand, auraptene, scopoletin, and praeruptorin inhibit the capacity for migration, invasion, and metastasis of cervical tumor cells, mainly by inhibiting the expression and activity of matrix metalloproteinase-2 and -9. The PI3K/Akt signal pathway appears to be central to the anti-tumor activity of the coumarins analyzed in this review. In addition, auraptene, osthole, and praeruptorin are useful in sensitizing tumor cells to radiotherapy or chemotherapeutic molecules, such as FOLFOX, cisplatin, or DOX. Coumarins offer an excellent possibility for developing new drugs as complementary medicine with an integrative approach against cervical cancer.

Comprehensive bioinformatic analysis reveals oncogenic role of H2A.Z isoforms in cervical cancer progression

Objectives

Cervical cancer ranks as the fourth most common neoplasia in women worldwide in which epigenetic alterations play an important role. Several studies have reported pro-oncogenic role of the histone variant H2A.Z in different types of cancer; however, the role of H2A.Z in cervical cancer remains poorly studied. This study aimed to determine the potential role of H2A.Z in cervical cancer through a bioinformatic approach.

Materials and Methods

H2A.Z expression was analyzed in The Human Protein Atlas, The Cancer Genome Atlas, and Gene Expression Omnibus datasets. The promoter regions of H2AZ1 and H2AZ2 genes were downloaded from Expasy, and the prediction of transcription factor binding motifs was performed using CONSITE, Alibaba, and ALGGEN. ChIP-seq and RNA-seq data from HeLa-S3 cells were downloaded from ENCODE. The discovery motif was investigated using MEME-ChIP. The functional annotation was examined in Enrich.

Results

The expression of H2A.Z is elevated in cervical cancer. Interestingly, DNA methylation, copy number, and transcription factors AP2α and ELK1 are involved in H2A.Z overexpression. Additionally, H2A.Z is enriched on promoter and enhancer regions of genes involved in pathways associated with cancer development. In these regions, H2A.Z enables the recruitment of transcription factors such as NRF1, NFYA, and RNA Pol II. Finally, H2A.Z allows the expression of genes associated with proliferation in patients with cervical cancer.

Conclusion

Our findings suggest that H2A.Z overexpression and its presence in promoters and enhancers could be regulating the transcription of genes involved in cervical carcinogenesis.

Metabolic Reprogramming in Cancer: Role of HPV 16 Variants

Metabolic reprogramming is considered one of the hallmarks in cancer and is characterized by increased glycolysis and lactate production, even in the presence of oxygen, which leads the cancer cells to a process called “aerobic glycolysis” or “Warburg effect”. The E6 and E7 oncoproteins of human papillomavirus 16 (HPV 16) favor the Warburg effect through their interaction with a molecule that regulates cellular metabolism, such as p53, retinoblastoma protein (pRb), c-Myc, and hypoxia inducible factor 1α (HIF-1α). Besides, the impact of the E6 and E7 variants of HPV 16 on metabolic reprogramming through proteins such as HIF-1α may be related to their oncogenicity by favoring cellular metabolism modifications to satisfy the energy demands necessary for viral persistence and cancer development. This review will discuss the role of HPV 16 E6 and E7 variants in metabolic reprogramming and their contribution to developing and preserving the malignant phenotype of cancers associated with HPV 16 infection.

Natural isoflavonoids in invasive cancer therapy: From bench to bedside

Cancer is a public health problem worldwide, and one of the crucial steps within tumor progression is the invasion and metastasis of cancer cells, which are directly related to cancer-associated deaths in patients. Recognizing the molecular markers involved in invasion and metastasis is essential to find targeted therapies in cancer. Interestingly, about 50% of the discovered drugs used in chemotherapy have been obtained from natural sources such as plants, including isoflavonoids. Until now, most drugs are used in chemotherapy targeting proliferation and apoptosis-related molecules. Here, we review recent studies about the effect of isoflavonoids on molecular targets and signaling pathways related to invasion and metastasis in cancer cell cultures, in vivo assays, and clinical trials. This review also reports that glycitein, daidzein, and genistein are the isoflavonoids most studied in preclinical and clinical trials and displayed the most anticancer activity targeting invasion-related proteins such as MMP-2 and MMP-9 and also EMT-associated proteins. Therefore, the diversity of isoflavonoids is promising molecules to be used as chemotherapeutic in invasive cancer. In the future, more clinical trials are needed to validate the effectiveness of the various natural isoflavonoids in the treatment of invasive cancer.

Cytotoxicity of Ficus Crocata Extract on Cervical Cancer Cells and Protective Effect against Hydrogen Peroxide-Induced Oxidative Stress in HaCaT Non-Tumor Cells

Oxidative stress causes several chronic diseases including cancer. Some chemotherapeutic agents are not selective against tumor cells, causing oxidative stress in non-tumor cells. This study aimed to evaluate the cytotoxic effect of acetone extract of Ficus crocata (Miq.) Mart. ex Miq. (F. crocata) leaves (Ace-EFc) on cervical cancer cells, as well as its protective effect on hydrogen peroxide (H₂O₂)-induced lipoperoxidation and cytotoxicity in non-tumor HaCaT cells. Antioxidant activity was determined using the DPPH and ABTS radicals. Cell viability and lipoperoxidation were determined with MTT and 1-methyl-2-phenylindole assays, respectively. A model of H₂O₂-induced cytotoxicity and oxidative damage in HaCaT cells was established. HaCaT cells were exposed to the extract before or after exposure to H₂O₂, and oxidative damage and cell viability were evaluated. Ace-EFc inhibited the DPPH and ABTS radicals and showed a cytotoxic effect on SiHa and HeLa cells. Furthermore, the extract treatment had a protective effect on hydrogen peroxide-induced lipoperoxidation and cytotoxicity, avoiding the increase in MalonDiAldehyde (MDA) levels and the decrease in cell viability (p < 0.001). These results suggest that the metabolites of F. crocata leaves possess antioxidant and cytoprotective activity against oxidative damage. Thus, they could be useful for protecting cells from conditions that cause oxidative stress.

Long non-coding RNAs as new players in cervical carcinogenesis: an update

Cervical cancer (CC) is the fourth most common cancer in women worldwide. Therefore, it is very important to understand cervical carcinogenesis, as well as the molecular mechanisms and signaling pathways involved in this process, in order to develop new strategies that contribute to diagnosis, prognosis and treatment of cervical cancer. Infection by high risk-human papillomavirus (HR-HPV) is a key event in cervical carcinogenesis, as well as, other factors, such as sociodemographics, lifestyle, sexual behavior, etc. In recent years, it has been shown that long non-coding RNA (lncRNA) are involved in CC and can be classified into tumor promoters or suppressors. Currently, several studies have analyzed the molecular mechanisms of some lncRNA in CC that might be acting, such as 1) competing endogenous RNAs (ceRNAs), 2) activators of signaling pathways, and 3) transcriptional regulators of genes. In this review, we summarized the more recent information on lncRNA and their role in the development of CC.

Integrin subunit β1 and laminin γ1 chain expression: a potential prognostic biomarker in cervical cancer

Aim: The aim of this study was to analyze the prognostic value of integrin subunit β1 and laminin γ1 chain in patients with cervical cancer (CC). Materials & methods: The study included 96 samples. Cytological diagnosis, human papillomavirus (HPV) genotyping, HPV integration status and integrin subunit β1 and laminin γ1 chain expressions were performed or determined using Papanicolaou smear, INNO-LiPA^® Genotyping Extra Kit, in situ hybridization, and immunocytochemistry, respectively. The association between variables was calculated using chi-squared and Fisher's exact test; logistic regression analysis was performed to calculate odds ratios and CI at 95%. Results: Our results show that integrin subunit β1 and laminin γ1 chain expressions increase according to tumor progression. Integrin subunit β1 and laminin γ1 chain expressions are associated with cytological diagnosis (p < 0.001 and p = 0.001, respectively) and laminin γ1 chain expression with the integration status of HPV (p < 0.001). Moderate/high expressions of integrin subunit β1 and laminin γ1 chain were correlated with overall survival and increased risk of CC (6.86 and 3.75, respectively), the odds ratio was 12.91 when the moderate/high expression of integrin subunit β1 and laminin γ1 chain were combined. Conclusion: Our results suggest that integrin subunit β1 and laminin γ1 chain expressions could be a prognostic biomarker in CC.

Phytochemical profile and antiproliferative effect of Ficus crocata extracts on triple-negative breast cancer cells

Background

Some species of the Ficus genus show pharmacological activity, including antiproliferative activity, in cell lines of several cancer Types. ficus crocata is distributed in Mexico and used in traditional medicine, as it is believed to possess anti-inflammatory, analgesic, and antioxidant properties. However, as of yet, there are no scientific reports on its biological activity. This study aims to evaluate the phytochemical profile of F. crocata leaf extracts and their effects on breast cancer MDA-MB-231 cells proliferation. Moreover, the study aims to unearth possible mechanisms involved in the decrease of cell proliferation.

Methods

The extracts were obtained by the maceration of leaves with the solvents hexane, dichloromethane, and acetone. The phytochemical profile of the extracts was determined using gas chromatography coupled with mass analysis. Cell proliferation, apoptosis, and cell cycle analysis in MDA-MB-231 cells were determined using a Crystal violet assay, MTT assay, and Annexin-V/PI assay using flow cytometry. The data were analyzed using ANOVA and Dunnett’s test.

Results

The hexane (Hex-EFc), dichloromethane (Dic-EFc), and acetone (Ace-EFc) extracts of F. crocata decreased the proliferation of MDA-MB-231 cells, with Dic-EFc having the strongest effect. Dic-EFc was fractioned and its antiproliferative activity was potentiated, which enhanced its ability to induce apoptosis in MDA-MB-231 cells, as well as increased p53, procaspase-8, and procaspase-3 expression.

Conclusions

This study provides information on the biological activity of F. crocata extracts and suggests their potential use against triple-negative breast cancer.

Ezrin and E-cadherin expression profile in cervical cytology: a prognostic marker for tumor progression in cervical cancer

Background

Cervical cancer (CC) is the fourth cause of mortality by neoplasia in women worldwide. The use of immunomarkers is an alternative tool to complement currently used algorithms for detection of cancer, and to improve selection of therapeutic schemes. Aberrant expression of Ezrin and E-cadherin play an important role in tumor invasion. In this study we analyzed Ezrin and E-cadherin expression in liquid-based cervical cytology samples, and evaluated their potential use as prognostic immunomarkers.

Methods

Immunocytochemical staining of Ezrin and E-cadherin was performed in cervical samples of 125 patients. The cytological or histological diagnostic was performed by Papanicolaou staining or H&E staining, respectively. HPV genotyping was determined using INNO-LIPA Genotyping Extra kit and the HPV physical status by in situ hybridization. Ezrin expression in HaCaT, HeLa and SiHa cell lines was determined by immunocytochemistry, immunofluorescence and Western blot.

Results

High Ezrin expression was observed in cervical cancer samples (70%), samples with multiple infection by HR-HPV (43%), and samples with integrated viral genome (47%). High Ezrin expression was associated with degree of SIL, viral genotype and physical status. In contrast, low E-cadherin expression was found in cervical cancer samples (95%), samples with multiple infection by HR-HPV/LR-HPV (87%) and integrated viral genome (72%). Low E-cadherin expression was associated with degree of SIL and viral genotype. Interestingly, Ezrin nuclear staining was associated with degree of SIL and viral genotype. High Ezrin expression, high percent of nuclear Ezrin and low E-cadherin expression behaved as risk factors for progression to HSIL and cervical cancer.

Conclusions

Ezrin and E-cadherin expression profile in cervical cytology samples could be a potential prognostic marker, useful for identifying cervical lesions with a high-risk of progression to cervical cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4243-7) contains supplementary material, which is available to authorized users.