Project description:Advanced ovarian cancer is the most lethal gynecologic malignancy in the United States. Currently patients are treated by surgical cytoreductive surgery with the aim of reducing tumor burden to microscopic disease followed by adjuvant combined treatment with a platinum and taxane containing chemotherapy, which affords 80% of patients an initial complete response. However, Abdominal and pelvic recurrence rates are high and response to further chemotherapy is limited. Attempts at introducing biologic therapeutic agents to improve outcome in this disease are ongoing, while prognostic or predictive biomarkers that can stratify patients for treatment are still lacking. Using transcriptome profiling of microdissected tissue samples from high-grade serous ovarian cancer patients, we identified a cancer associated fibroblast (CAF) specific gene signature. Versican, which encodes a extracellular matrix protein, was one of the identified genes which demonstrated up-regulation in cancer stroma. To investigate the function roles, signaling machanism and the effect of versican treatment on ovarian cancer cells, transcriptome profiling of versican treated OVCA433 high-grade serous ovarian cancer cells was performed. High grade serous ovarian cancer cell line OVCA433 was used. Total RNA was isolated from control samples and versican treated cancer cell samples at 48 hours post-treatment followed by cDNA synthesis, IVT and biotin labeling. Samples were then hybridized onto Affymetrix Human genome U133 plus 2.0 microarrays. For each treatment group, three independent samples were prepared for the microarray experiment.
Project description:<p>BRCA1 mutations are a hallmark of hereditary ovarian cancer, strongly linked to deficiencies in homologous recombination (HR) DNA repair and impaired DNA replication fork protection. However, its roles in cancer progression beyond maintaining genomic integrity remain poorly understood. Through metabolomics approaches, we found BRCA1-deficiency strikingly increased choline metabolism. Loss of BRCA1 promotes choline uptake through upregulating choline transporter-like protein 4 (CTL4). BRCA1 directly binds and recruits EZH2-mediated H3K27Me3 deposition to CTL4 promoter. CTL4 was therefore overexpressed in ovarian cancer tissues with BRCA1 mutations. Furthermore, BRCA1-deficiency significantly promotes ovarian cancer invasion, while inhibition of CTL4 reverses the high metastatic potential of BRCA1-deficient ovarian cancer cells, suggesting the functionality and specificity of CTL4 as a therapeutic target. Additionally, we discovered that phosphocholine, the choline metabolite increased by CTL4 overexpression, interacted with and stabilized the epithelial-to-mesenchymal transition inducer FAM3C in BRCA1-deficient ovarian cancer cells. Importantly, we identified a potent CTL4 inhibitor, DT-13, which significantly reduces choline metabolism and effectively suppresses metastasis in BRCA1-deficient ovarian cancers. Therefore, our study uncovers a mechanism underlying metastasis in BRCA1-deficient cancers and identifies CTL4 as a therapeutic target for metastatic ovarian cancer patients with BRCA1 mutations.</p>
Project description:The tumor derived Versican (VCAN) can be a possible mediator of the host NF-κB pathway in cancer pathogenesis. In this context, we defined VCAN function in the pathogenesis development in vitro with cell lines as well as in vivo with mouse model. We used the proteomic technique to quantify VCAN integrity and relative abundancy produced by different cancer cell lines and to link this information to our pre-existing data. These results helped us to finalise our dataset and define more clearly VCAN influence tumor development.
Project description:Ovarian clear cell carcinoma (OCCC) shows unique clinical features including an association with endometriosis and poor prognosis. We previously reported that the contents of endometriotic cysts, especially high concentrations of free iron, are a possible cause of OCCC carcinogenesis through iron-induced persistent oxidative stress. In this study, we conducted gene expression microarray analysis using 38 ovarian cancer cell lines and identified genes commonly expressed in both OCCC cell lines and clinical samples, which comprise an OCCC gene signature. The OCCC signature reproducibly predicts OCCC specimens in other microarray data sets, suggesting that this gene profile reflects the inherent biological characteristics of OCCC. The OCCC signature contains known markers of OCCC, such as hepatocyte nuclear factor-1b (HNF-1b) and versican (VCAN), and other genes that reflect oxidative stress. Expression of OCCC signature genes was induced by treatment of immortalized ovarian surface epithelial cells with the contents of endometriotic cysts, indicating that the OCCC signature is largely dependent on the tumor microenvironment. Induction of OCCC signature genes is at least in part epigenetically regulated, as we found hypomethylation of HNF-1b and VCAN in OCCC cell lines. This genomewide study indicates that the tumor microenvironment induces specific gene expression profiles that contribute to the development of distinct cancer subtypes. Affymetrix Human Genome U133A 2.0 Array was conducted for 38 ovarian cancer cell lines (13 OCCC cell lines and 25 non-OCCC cell lines). All specimens were arrayed in parallel and used for RMA normalization.
Project description:Epithelial ovarian cancer (EOC) is the deadliest gynecological cancer. MicroRNAs (miRNAs) are small non-coding RNAs that play important roles in gene regulation and their dysregulation is associated with many diseases. In this study, we determined the expression and function of miR-590-3p in EOC. We found that miR-590-3p levels were higher in high-grade carcinoma when compared to low-grade or tumours with low malignant potential. Interestingly, plasma levels of miR-590-3p were significantly higher in EOC patients than in subjects with benign gynaecological disorders. Transient transfection of miR-590-3p mimics, or stable transfection of mir-590, increased cell growth, migration, and invasion. In vivo studies revealed that mir-590 accelerated tumour growth and metastasis. Using a cDNA microarray, we identified Forkhead box A2 (FOXA2) and Versican (VCAN) as a top downregulated and a top upregulated gene, respectively, by mir-590. We showed that miR-590-3p targeted FOXA2 3’ UTR to suppress its expression. In addition, knockdown of FOXA2 by siRNAs or knockout of FOXA2 by CRISPR/Cas9 enhanced cell proliferation, migration, and invasion. Overexpression of FOXA2 decreased, while knockout of FOXA2 increased, VCAN mRNA and protein levels and ChIP-qPCR revealed that FOXA2 binds to VCAN promoter. Interrogation of the TCGA ovarian cancer database revealed a negative relationship between FOXA2 and VCAN mRNA levels in EOC tumours and that high FOXA2/low VCAN mRNA levels in tumours were positively correlated with patient survival. Finally, overexpression of FOXA2 or silencing of VCAN reversed the effects of mir-590. These findings demonstrate that miR-590-3p promotes EOC development via a novel FOXA2-VCAN pathway.
Project description:Advanced ovarian cancer is the most lethal gynecologic malignancy in the United States. Currently patients are treated by surgical cytoreductive surgery with the aim of reducing tumor burden to microscopic disease followed by adjuvant combined treatment with a platinum and taxane containing chemotherapy, which affords 80% of patients an initial complete response. However, Abdominal and pelvic recurrence rates are high and response to further chemotherapy is limited. Attempts at introducing biologic therapeutic agents to improve outcome in this disease are ongoing, while prognostic or predictive biomarkers that can stratify patients for treatment are still lacking. Using transcriptome profiling of microdissected tissue samples from high-grade serous ovarian cancer patients, we identified a cancer associated fibroblast (CAF) specific gene signature. Versican, which encodes a extracellular matrix protein, was one of the identified genes which demonstrated up-regulation in cancer stroma. To investigate the function roles, signaling machanism and the effect of versican treatment on ovarian cancer cells, transcriptome profiling of versican treated OVCA433 high-grade serous ovarian cancer cells was performed.
Project description:Ovarian clear cell carcinoma (OCCC) shows unique clinical features including an association with endometriosis and poor prognosis. We previously reported that the contents of endometriotic cysts, especially high concentrations of free iron, are a possible cause of OCCC carcinogenesis through iron-induced persistent oxidative stress. In this study, we conducted gene expression microarray analysis using 38 ovarian cancer cell lines and identified genes commonly expressed in both OCCC cell lines and clinical samples, which comprise an OCCC gene signature. The OCCC signature reproducibly predicts OCCC specimens in other microarray data sets, suggesting that this gene profile reflects the inherent biological characteristics of OCCC. The OCCC signature contains known markers of OCCC, such as hepatocyte nuclear factor-1b (HNF-1b) and versican (VCAN), and other genes that reflect oxidative stress. Expression of OCCC signature genes was induced by treatment of immortalized ovarian surface epithelial cells with the contents of endometriotic cysts, indicating that the OCCC signature is largely dependent on the tumor microenvironment. Induction of OCCC signature genes is at least in part epigenetically regulated, as we found hypomethylation of HNF-1b and VCAN in OCCC cell lines. This genomewide study indicates that the tumor microenvironment induces specific gene expression profiles that contribute to the development of distinct cancer subtypes.