Project description:Profiling of proteolytic events mouse kidneys during cisplatin-induced kidney damage. Kidneys from vehicle-treated mice are compared to cisplatin-treated mice and cisplatin treatment in animals preconditioned by hypoxia or calory restriction regimes.
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 (37M-0C) with different concentrations of cisplatin, liposomal cisplatin or empty liposomes were added and incubated for 72 h at 37M-0C in a 5% CO2 incubator. In case of A2780sens cells, 1.72 M-5M cisplatin (IC50 concentration) and in case of A2780cis cells 8.94 M-5M 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: 0.80M-5mol lipid, A2780cis: 4.15 M-5mol 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 -80M-0C until RNA extraction.
Project description:The aim of this experiment was to evaluate the changes in gene expression in response to hypoxia and/or cisplatin in an ovarian cancer cell line model. A2780 (cisplatin-sensitive) and A2780cis (cisplatin-resistant) cell lines were treated with cisplatin in normoxia or hypoxia (0.5% O2) for 72 hours. RNA was extracted from three independent biological replicates for each condition: A2780 (normoxia, untreated); A2780 (hypoxia, untreated); A2780 (normoxia, cisplatin); A2780cis (hypoxia, cisplatin), A2780cis (normoxia, untreated); A2780cis (hypoxia, untreated); A2780cis (normoxia, cisplatin); A2780cis (hypoxia, cisplatin) and interrogated on Affymetrix Human Gene ST 1.0 arrays.
Project description:Genomic analyses of SCC have yet to yield significant strategies against pathway activation to improve treatment. Platinum-based chemotherapy remains the mainstay of treatment for SCC of different histotypes either as a single agent or alongside other chemotherapeutic drugs or radiotherapy; however, resistance inevitably emerges, which limits the duration of treatment response. To elucidate mechanisms that mediate resistance to cisplatin, we compared drug-induced perturbations to gene expression between cisplatin-sensitive and -resistant SCC cells. Cisplatin-sensitive and -resistant SCC cells were identified through MTS assay. Gene expression profiling (Affymetrix GeneChip 1.0ST) was performed to identify putative genes and cellular pathways that may be associated with cellular response to cisplatin.
Project description:This SuperSeries is composed of the following subset Series: GSE15372: Expression data from A2780 (cisplatin-sensitive) and Round5 A2780 (cisplatin-resistant) cell lines. GSE15373: Promoter CpG island methylation data from A2780 (cisplatin-sensitive) and Round5 A2780 (cisplatin-resistant) cell lines. Refer to individual Series
Project description:Understanding the mechanism of resistance in platinum-based regimens for the treatment of high-grade serous ovarian cancer (HGSOC) is important for identifying new therapeutic targets to improve the clinical outcome of ovarian cancer patients. Mass spectrometry-based proteomic strategy was applied to spheroidal cisplatin sensitive and resistant HGSOC generated cell lines in the absence and presence of cisplatin drug. A complete expressed HGSOC proteome and phosphoproteome was characterized in cisplatin sensitive and resistant HGSOC cell lines providing insight into the mechanism of resistance development. PCA analysis showed that phosphorylation of a few proteins provides better classification than the whole proteome of the cellular subtypes. Specifically, a distinctive phosphoproteomic signature between cisplatin sensitive and resistant cell lines in the absence of drug was observed. This same phosphoproteomic signature was observed in our cisplatin sensitive cell line in the absence and presence of drug, indicating a vital role for phosphorylation of proteins in resistance development to cisplatin. The most phosphorylated protein was sequestosome (p62/SQSTM1). Differential expressions of apoptosis by the prognostic factor ratio of Bcl-2/Bax and autophagy, known to be regulated by p62/SQSTM1, was validated in the proteome data and by western blot analysis. A significant increase in apoptosis in the presence of cisplatin was observed in only the sensitive cell line while autophagy revealed increased expression in the resistant relative to sensitive cell line. Furthermore, site specific phosphorylation on 20 modified residues of sequestosome was characterized. Elevated expression of phosphorylation of sequestosome in resistant HGSOC cell lines was validated with western blot analysis. Here, we propose phosphorylation of sequestosome to be a marker and key in cisplatin resistance development in HGOSC ovarian cancers by shuttling ubiquitinated proteins to the autophagy pathway and influencing down-regulation of apoptosis.
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:Sensitivity to platinum-based combination chemotherapy is associated with a favorable prognosis in the patients of non-small cell lung cancer (NSCLC). Here, our results obtained from analyses of the Gene Expression Omnibus database of NSCLC patients showed that cartilage acidic protein 1 (CRTAC1) plays a role in the response to platinum-based chemotherapy. Overexpression of CRTAC1 increased sensitivity to cisplatin in vitro, whereas knockdown of CRTAC1 decreased chemosensitivity of NSCLC cells. In vivo mouse experiments showed that CRTAC1 overexpression increased the antitumor effects of cisplatin. CRTAC1 overexpression promoted NFAT transcriptional activation by increasing intracellular Ca2+ levels, thereby inducing its regulated STUB1 mRNA transcription and protein expression, accelerating Akt1 protein degradation, and in turn enhancing cisplatin-induced apoptosis. Taken together, the present results indicate that CRTAC1 overexpression increases the chemosensitivity of NSCLC to cisplatin treatment by inducing Ca2+-dependent Akt1 degradation and apoptosis, suggesting the potential of CRTAC1 as a biomarker for predicting cisplatin chemosensitivity. Our results further reveal that modulating the expression of CRTAC1 could be a new strategy for increasing the efficacy of cisplatin in chemotherapy of NSCLC patients.
Project description:The absence of the Rb tumor suppressor gene changes levels/activities of transcription factors (e.g., E2F and p53) which alter gene expression patterns, related to cell cycle control and cellular response to DNA damage. Cisplatin is a genotoxic chemotherapeutic agent and wildtype or Rb null cells have different sensitivities to cisplatin-induced cytotoxicity. We used microarrays to compare global profiles of gene expression and distinct responses of wildtype and Rb null MEFs in response to cisplatin. Experiment Overall Design: Primary wildtype or Rb null MEFs were generated from embryos at embryonic day 13.5 and cultured to passage 2. Wildtype or Rb null MEFs were either untreated or treated with 16 microM cisplatin for 24 hours prior to harvest and RNA extraction. Four different RNA samples (wildtype or Rb-/- MEFs, untreated or cisplatin-treated) were used for hybridization in triplate to Affimatrix Chips. Then, the total of 12 hybridizations were divided into 4 subseries: UT-Rb, UT-WT, CP-Rb, CP-Wt, and each subseries contained three samples (hybridization 1-3 or a-c).