Project description:High-grade serous ovarian cancer is the most aggressive histological type of epithelial ovarian cancer, which is characterized by a high frequency of somatic TP53 mutations. To provide a better understanding of the molecular mechanisms involved in the pathogenesis of these cancers and to develop a risk classification system, we conducted profiling of the copy number alterations present in these tumors. Thirty patients who were diagnosed as high-grade serous ovarian cancer were recruited in this study. Affymetrix SNP array were performed according to the manufacturer's directions on DNA extracted from high-grade serous ovarian cancer tissues or peripheral blood samples. The Japanese Serous Ovarian Cancer Study Group
Project description:Ovarian cancer is the most lethal gynecologic cancer. High-grade serous ovarian carcinoma (HGSOC) is the most common histologic subtype, accounting for three quarters of ovarian cancer. To clarify the changes of gene expression in serous ovarian cancer, we performed lncRNA and mRNA microarrays to identify differentially expressed lncRNAs and mRNAs in High-grade and Low-grade serous ovarian carcinoma compared with Normal fallopian tube.
Project description:Profiling of loss of heterozygosity (LOH) in HGSC, subcrouping HGSC by LOH-based clustering and comparing to the LOH profiles of triple-negative breast cancer [previously submitted; GSE19594]. Study for the correlation of LOH burdern and LOH-based subgroups to clinical response to platinum-based chemotherapy in patients suffered from HGSC. SNP data (Affymetrix GenChip 250K SNP Nsp) from 47 high grade serous ovarian cancer were generated and used for LOH and copy number analysis, LOH-based hierarchical clustering to subclassify HGSC, and comparison to the chromosomal alterations in high grade brest cancer. The associstion between LOH-based subgroups and LOH burden and clinical resposne to platinum-based chemotherapy was investigated. The results were validated in two independent public opening datasets.
Project description:Low-grade serous ovarian carcinoma is believed to arise from serous borderline ovarian tumors, yet the progression from serous borderline tumors to low-grade serous ovarian carcinoma remains poorly understood. The purpose of this study was to identify differentially expressed genes between the two groups. Expression profiles were generated from 6 human ovarian surface epithelia (HOSE), 8 serous borderline ovarian tumors (SBOT), 13 low-grade serous ovarian carcinomas (LG), and 22 high-grade serous ovarian carcinomas (HG). The anterior gradient homolog 3 (AGR3) gene was found to be highly upregulated in serous borderline ovarian tumors; this finding was validated by real-time quantitative RT-PCR, Western blotting, and immunohistochemistry. Anti-AGR3 immunohistochemistry was performed on an additional 56 LG and 103 HG tissues and the results were correlated with clinical data. Expression profiling determined that 1254 genes were differentially expressed (P < 0.005) between SBOT, LG and HG tumors. Serous borderline ovarian tumors exhibited robust positive staining for AGR3, with a lower percentage of tumor cells stained in LG and HG. Immunofluorescence staining indicated that AGR3 expression was limited to ciliated cells. Tumor samples with a high percentage (>10%) of AGR3 positively stained tumor cells were associated with improved longer median survival in both the LG (P = 0.013) and HG (P = 0.008) serous ovarian carcinoma groups. The progression of serous borderline ovarian tumors to low-grade serous ovarian carcinoma may involve the de-differentiation of ciliated cells. AGR3 could serve as a prognostic marker for survival in patients with low-grade and high-grade serous ovarian carcinomas. Total RNA were extracted from microdissected human ovarian surface epithelia (HOSE, n=6), and microdissected serous borderline ovarian tumors (LMP, n=8), low-grade serous ovarian carcinomas (LGOSC, n=13), and 22 high-grade serous ovarian carcinomas (HGOSC, n=22). Gene Expression profiles were then generated with commercial GeneChip Human Genome U133 Plus 2.0 Array. dChip was used to identify significant differentially expressed genes between LMP/LGOSC and HGOSC
Project description:The goal of the study was to collect ovarian cancer samples for gene expression profiling (n = 529). The data will be used in several publications, the first of which described molecular signatures associated with high-grade serous ovarian cancer subtype
Project description:Comparative genomic hybridization analysis on advanced stage high-grade serous ovarian cancer. CGH was performed on 42 DNA isolated from microdissected advanced stage high-grade serous ovarian cancer.
Project description:Objective: Ovarian tumors of low-malignant potential (LMP) and low-grade serous ovarian carcinomas are thought to represent different stages on a tumorigenic continuum and to develop along pathways distinct from that of high-grade serous ovarian carcinoma. Past studies have utilized gene expression profiles to support this theory. The objective of the current study was to identify new genes whose expression profiles in LMP ovarian tumors and low-grade ovarian carcinomas differ from that in high-grade ovarian carcinomas. Methods: We used RNA from 3 normal human ovarian surface epithelia (HOSE) and from 10 low-grade and 10 high-grade serous ovarian carcinoma samples to perform gene expression profiling. Using real-time reverse-transcription polymerase chain reaction (RT-PCR), we evaluated changes in PAX2 mRNA expression in cDNA created from RNA extracted from an independent set of ovarian tissue samples (7 LMP tumors and 17 low-grade and 23 high-grade serous carcinomas). We also examined PAX2 expression using Western blot analysis of protein extracted from a set of ovarian LMP and low- and high-grade carcinoma tissue samples. Additionally, we used immunohistochemistry (IHC) to validate PAX2 overexpression in a third independent set of paraffin ovarian tissue sections from 17 LMP tumors and 16 low- and 257 high-grade carcinomas. Results: Gene profiling revealed higher expression of PAX2 in low-grade than in high-grade ovarian carcinomas. Real-time RT-PCR demonstrated a statistically significant difference in median PAX2 mRNA expression, expressed as fold change, among ovarian LMP tumor (1837.38), low-grade (183.12), and high-grade (3.72) carcinoma samples (p=0.015). Western blot analysis revealed strong PAX2 expression in ovarian LMP and low-grade carcinoma samples but no PAX2 protein expression in high-grade carcinomas. On IHC, more LMP tumor and low-grade carcinoma samples expressed moderate to high levels of PAX2 than did high-grade ovarian carcinoma samples. The numbers of samples with strong nuclear staining was significantly higher for ovarian LMP tumors (10 of 17, p<0.001) and low-grade serous carcinomas (10 of 16, p<0.001) than for high-grade carcinomas (27 of 257). Discussion: Our identification and validation of higher PAX2 expression in ovarian LMP tumors and low-grade serous carcinomas than in high-grade carcinomas supports the two-tiered hypothesis that the first two are on a continuum and are distinct from high-grade ovarian carcinomas. PAX2 may represent a potential biomarker and future therapeutic target for individualizing chemotherapy for ovarian LMP tumors and low-grade carcinomas in the future.
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:To demonstrate the use of a whole-genome oligonucleotide array to perform expression profiling on a series of microdissected late-stage, high-grade papillary serous ovarian adenocarcinomas to establish a prognostic gene signature correlating with survival and to identify novel survival factors in ovarian cancer. Advanced stage papillary serous tumors of the ovary are responsible for the majority of ovarian cancer deaths, yet the molecular determinants modulating patient survival are poorly characterized. We identify and validate a prognostic gene expression signature correlating with survival in a series of microdissected serous ovarian tumors. Experiment Overall Design: We identified 53 advanced stage, high-grade primary tumor specimens and 10 normal ovarian surface epithelium (OSE) brushings.