Project description:The high frequency of somatic copy number alterations, as opposed to point mutations, is considered a unique feature of high-grade serous ovarian carcinoma (HGSOC). Amplification-dependent overexpression of RECQL4, which participates in DNA replication and repair, mediates the development of various cancers, but its pathobiological and clinical roles are poorly understood. Here, using bioinformatics analysis, RECQL4 amplification was found to occur in 27% of HGSOC samples in the TCGA cohort. RECQL4 was found to be upregulated and associated with a poor prognosis based on the immunohistochemistry staining of HGSOC. Functionally, RECQL4 overexpression increased proliferation and invasion of ovarian cancer cells both in vitro and in vivo. RECQL4 silencing had the opposite effects. In addition, RECQL4 knockdown enhanced the sensitivity of ovarian cancer cells to cisplatin and PARP inhibitor (PARPi). Further mechanistic investigations revealed that MAFB was a downstream target of RECQL4. The oncogenic effect of RECQL4 was attenuated after MAFB knockdown. Moreover, RECQL4 overexpression was negatively regulated by the tumour suppressor miR-10a-5p. Collectively, these findings indicate that genomic amplification and low expression of miR-10a-5p contribute to RECQL4 overexpression in ovarian cancer. This is the first study to reveal the oncogenic functions and clinical significance of RECQL4 in ovarian cancer.
Project description:Ovarian clear cell carcinoma (OCCC) is a morphologically and biologically distinct subtype of ovarian carcinomas. We previously reported a gene expression profile characteristic of OCCC (OCCC signature), which contains hepatocyte nuclear facter-1b ( HNF-1b). To elucidate the biological role of HNF-1b in OCCC, we performed the suppression of the HNF-1b expression in human ovarian cancer cell line RMG2 using short hairpin RNA. We are now evaluating the functional effect using these cells. Affimetrix Human Genome U133A plus 2.0 chips was conducted for HNF1b knockdown and non-silencing cells (five replicates each for RMG2-HNF1b-sh1 and RMG2-HNF1b-sh2, ten replicates for the RMG2-control). All specimens were arrayed in parallel and used for RMA normalization.
Project description:RNA-sequencing was performed to gain insight into the mechanism responsible for the mesenchymal-to-epithelial transition (MET) induced by loss of long non-coding RNA (lncRNA) DNM3OS in SKOV3 ovarian cancer cells. Following siRNA-mediated knockdown of DNM3OS or non-targeting control, RNA-sequencing was performed. This high-throughput data revealed knockdown of DNM3OS down-regulated the expression of genes and pathways known to induce EMT in ovarian cancer.
Project description:CHSY1 has high expression in malignant tumor cells, such as colorectal cancer and ovarian cancer, and is associated with poor prognosis.The proliferation and invasion of ovarian cancer cells are weakened after knocking down CHSY1 with shRNA transfected We used microarrays to detail the global programme of gene expression underlying CHSY1 knockdown and identified distinct classes of up-regulated and down-regulated genes.
Project description:Eukaryotic initiation factor 5A2 (EIF5A2) acts as a candidate oncogene and is located on human chromosome 3q26, a region frequently amplified in several tumors. Accumulating evidence shows that EIF5A2 plays important roles in enhancing anchorage-independent growth, xenograft tumour growth, increasing cancer cell metastasis and promoting treatment resistance through multiple pathways. Here, we showed that EIF5A2 knockdown reduced the expression of KLF4, which could partially rescue stem-like properties abolished by EIF5A2 knockdown or strengthened by EIF5A2 overexpression, through the transcription factor E2F1, which directly bind to KLF4 promoter.
Project description:To discover the core gene expression features of CtBP1, CtBP2 differently regulated in ovarian cancer SKOV3 cells. The compared the whole transcript expression profiling between CtBP1 knockdown, CtBP2 knockdown and scramble control in ovarian cancer skov3 cells.