ABSTRACT: Transcriptional profiling of human ovarian cancer cells comparing control vehicle-treated A2780 and OVCAR-3 (Human ovarian cancer cell lines) cells with A2780 and OVCAR-3 cells treated with 5μM LS-98 for 24 hours.Goal was to determine the effects of LS-98 compound on the global A2780 and OVCAR-3 cells gene expression. One-condition experiment, control vehicle-treated A2780 and OVCAR-3 vs. LS098 treated-A2780 and OVCAR-3 cells. Biological replicates: 2 replicates.
Project description:The study was designed to determine the biological effects of novel marine alkaloid analog, FBA-TPQ on human ovarian cancer cells for its anti-tumor potential and the underlying mechanisms as a novel chemotherapeutic agent. Transcriptional profiling of human ovarian cancer cells comparing control vehicle-treated OVCAR-3(a human ovarian cancer cell line) cells with OVCAR-3 cells treated with 1000nM FBA-TPQ for 24 hours. Goal was to determine the effects of FBA-TPQ on global OVCAR-3 cells gene expression. One-condition experiment, control vehicle-treated OVCAR-3 vs. FBA-TPQ treated-OVCAR-3 cells. Biological replicates: 2 replicates.
Project description:The purpose of the study was to identify mRNA bound to HuR in the presence of doxorubicin in MCF7 cells. We collected cytoplasmic RNA from untreated and treated cells and detected differentially expressed genes (DEGs). We also coimmunoprecipitated HuR and IgG (as control) from doxorubicin treated cells. Comparison between HuR RIP and IgG RIP signals was used to discriminate specific mRNA bound to HuR. HuR coimmmunoprecipitated material was hybridized together with cytoplasmic mRNA of doxorubicin treated cells, enabling the fold enrichment calculation and the selection of mRNAs bound to HuR. Keywords: RIP-Chip, HuR, doxorubicin, MCF7, HuR consensus binding, post-transcriptional regulation. We subjected MCF7 cells to starvation for 24h and then we added doxorubicin at final concentration of 10 uM, profiling before and after 4 hours of treatment in biological quadruplicate (only on cytoplasmic mRNAs, as HuR was found in the cytoplasm). Differentially expressed genes, altered during the treatment, were identified. Data derived from HuR RIP-Chip and IgG RIP-Chip (in biological quadruplicate) allowed the identification of specific mRNAs bound to HuR. The comparison between HuR RIP-Chip and cytoplasmic extracts from doxorubicin treated cells (in biological triplicate) identified those genes that were more strictly bound to HuR independently from their expression levels.
Project description:Differences in gene expression in A2780C20 vs. A2780 and A2780 treated with temsirolimus at 24-hr and 48-hr. The A2780 are human ovarian carcinoma cellls were purchased to the European Collection of Cell Cultures (ECACC). The A2780CP20 are cisplatin resisatnt cells derived of the A2780 cells. A2780CP20 cells were generated by Dr. Robert Ozols (J. Natl. Cancer Inst. 84, 264-267 (1992) by treatment of A2780 cells with incresing concentrations of cisplatin. The goal of this study is to determine whether the cisplatin and temsirolimus resistance are co-regulated. The objectives of this study are to identify additional genes differentially expressed in cisplatin sensitive and cisplatin resistant ovarain cancer cells and the changes in gene expreession upon temsirolimus treatment of A2780 cells. RNA was isolated from A2780, A2780CP20, A2780 plus temsirolimus 24-hr, and A2780 plus temsirolimus 48-hr. Labelled samples were hybridized to Affymetrix GeneChip Gene 1.0 ST Human Arrays.
Project description:Cisplatin and carboplatin are the primary first-line therapies for the treatment of ovarian cancer. However, resistance to these platinum-based drugs occurs in the large majority of initially responsive tumors, subsequently resulting in a poor long-term prognosis. To model the onset of drug resistance, and investigate the DNA methylation alterations associated with cisplatin resistance, we treated clonally derived, drug-sensitive A2780 epithelial ovarian cancer cells with increasing concentrations of cisplatin. After several cycles of drug selection, the isogenic drug-sensitive and -resistant pairs were subjected to global CGI methylation microarray analyses. We treated clonally derived, drug-sensitive A2780 epithelial ovarian cancer cells with increasing concentrations of cisplatin. After several cycles of drug selection, the isogenic drug-sensitive and -resistant pairs were subjected to global CGI methylation analyses by differential methylation hybridization (DMH) using a customed 44K promoter CGI microarray.
Project description:Ovarian cancer is a deadly gynecological malignancy for which novel biomarkers and therapeutic targets are imperative for improving survival. To investigate the role of histone H1 in ovarian cancer cells, we overexpress a histone H1 variant, H1.3, in the OVCAR-3 epithelial ovarian cancer cell line. RNA was extracted from OV-3/H1.3(H) cells (OVCAR-3 with overexpression of H1.3) and control cells of OVCAR-3 transfected with vectors without H1.3. The microarray chip used was human Affymetrix ST1.0 array. Gene expression changes caused by overexpression of H1.3 in OVCAR-3 cells were identified. Affymetrix Human Exon 1.0 ST array was used to identify the changes in transcriptome of OVCAR-3 caused by overexpression of H1.3
Project description:Analysis of the ovarian cancer cell line OVCAR-5. A standard trypsin digest was carried out on the OVCAR-5 cell lysates which were then analysed in the un-fractionated and fractionated forms. Fractionation was completed using a peptide IEF separation method. All samples were analysed by nano-LC-ESI-MS/MS using a QTOF.
Project description:A2780 ovarian cancer cells and a cisplatin resistant derivate of A2780 cells, obtained from ECACC, UK, No. 93112519 [A2780] and No. 93112517 [A2780 cis] were seeded out in T-75 flasks at a density of 2x106 for A2780sens and 3x106 for A2780cis cells in 15 ml of medium and preincubated overnight. Medium was removed and 15 ml fresh medium (37°C) with different concentrations of cisplatin, liposomal cisplatin or empty liposomes were added and incubated for 72 h at 37°C in a 5% CO2 incubator. In case of A2780sens cells, 1.72 µM cisplatin (IC50 concentration) and in case of A2780cis cells 8.94 µM cisplatin (IC50 concentration) were added. Liposomal formulations contained equal cisplatin concentrations. Empty liposomes were added in the same concentration as the liposomal cisplatin, to analyze the impact of liposomal lipids (A2780sens: 0.80µmol lipid, A2780cis: 4.15 µmol lipid). After incubation, medium was removed and cells were washed thrice with 10 ml PBS. 1 ml RLT-buffer was added and cells lysates were stored at -80°C until RNA extraction.
Project description:The androgen receptor (AR) plays a key role in progression to incurable androgen-ablation resistant prostate cancer (PCA). We have identified three novel AR splice variants lacking the ligand binding domain (designated as AR3, AR4 and AR5) in hormone insensitive PCA cells. AR3, one of the major splice variants expressed in human prostate tissues, is constitutively active and its transcriptional activity is not regulated by androgens or antiandrogens. Immunohistochemistry analysis on tissue microarrays containing 429 human prostate tissue samples shows that AR3 is significantly upregulated during PCA progression and AR3 expression level is correlated with the risk of tumor recurrence after radical prostatectomy. Overexpression of AR3 confers ablation-independent growth of PCA cells while specific knock-down of AR3 expression (without altering AR level) in hormone resistant PCA cells attenuates their growth under androgen-depleted conditions in both cell culture and xenograft models, suggesting an indispensable role of AR3 in ablation-independent growth of PCA cells. Furthermore, AR3 may play a distinct yet essential role in ablation-independent growth through regulating a unique set of genes including AKT1, which are not regulated by the prototype AR. Our data suggest that aberrant expression of AR splice variants may be a novel mechanism underlying ablation-independence during PCA progression and AR3 may serve as a prognostic marker to predict patient outcome in response to hormonal therapy. Given that these novel AR splice variants are not inhibited by currently available anti-androgen drugs, development of new drugs targeting these AR isoforms may potentially be effective for treatment of ablation-resistant PCA. Total RNA was extracted from CWR-R1 and 22Rv1 cells treated with shAR3-1, shARa and the scrambled shRNA control, respectively. Each of CWR-R1 and 22Rv1 cells treated with shAR3-1 was compared with the scrambled shRNA control. The same experiments were performed for the cells treated with shARa.
Project description:Drug resistance poses a major challenge to ovarian cancer treatment. Understanding mechanisms of drug resistance is important for finding new therapeutic targets. In the present work, a cisplatin-resistant ovarian cancer cell line A2780-DR was established with a resistance index of 6.64. The cellular accumulation of cisplatin was significantly reduced in A2780-DR cells as compared to A2780 cells consistent with the general character of drug resistance. Quantitative proteomic analysis identified 340 differentially expressed proteins between A2780 and A2780-DR cells, which involve in diverse cellular processes, including metabolic process, cellular component biogenesis, cellular processes and stress responses. Expression levels of Ras-related proteins Rab 5C and Rab 11B in A2780-DR cells were lower than those in A2780 cells as confirmed by real-time quantitative PCR and western blotting. The short hairpin (sh)RNA-mediated knockdown of Rab 5C in A2780 cells resulted in markedly increased resistance to cisplatin whereas overexpression of Rab 5C in A2780-DR cells increases sensitivity to cisplatin, demonstrating that Rab 5C-dependent endocytosis plays an important role in cisplatin resistance. Our results also showed that expressions of glycolytic enzymes PKM, GPI, Aldolase, LDH, and PGK were down-regulated in drug resistant cells, indicating drug resistance in ovarian cancer is directly associated with a decrease in glycolysis. Furthermore, it was found that glutathione reductase were up-regulated in A2780-DR, while vimentin, HSP90, and Annexin A1 and A2 were down-regulated. Taken together, our results suggest that drug resistance in ovarian cancer cell line A2780 is caused by multifactorial traits, including the down-regulation of Rab 5C-dependent endocytosis of cisplatin, glycolytic enzymes and vimentin, and up-regulation of antioxidant proteins, suggesting Rab 5C is a potential target for treatment of drug-resistant ovarian cancer. This constitutes a further step towards a comprehensive understanding of drug resistance in ovarian cancer.