Project description:To identify genomic loci occupied by p53, we performed p53 ChIP-seq analysis of colorectal carcinoma cell line HCT116, breast carcinoma line MCF7, and osteosarcoma line SJSA treated with MDM2 inhibitor Nutlin.
Project description:To test the effects of uracil DNA glycosylase (UNG) loss on the formation of double strand breaks (DSBs) by the anti-cancer agent pemetrexed, we performed ChIP-seq for serine 139-phosphorylated H2AX (gammaH2AX), a marker of DSBs, in human cells wild-type or deficient for UNG in combination with pemetrexed treatment. UNG deficiency results in an increase in DSBs upon pemetrexed treatment, and we found that pemetrexed treatment induces DSBs at different genomic locations in UNG wild-type and knockout cells. Similar results were observed upon cisplatin treatment of UNG wild-type and knockout cells, and the genomic locations of DSBs were distinct between pemetrexed-treated and cisplatin-treated samples. Taken together, our results suggst differential mechanisms for DSB formation in UNG-competent and UNG-deficient cells. The genomic distribution of gammaH2AX in UNG WT and KO cells treated with pemetrexed or cisplatin was determined by ChIP-seq
Project description:Gene expression and pre-mRNA splicing events were examined in human breast adenocarcinoma (MCF7) cells treated or not with cisplatin and various siRNAs.
Project description:To determine effects of p53 activation on steady-state mRNA levels, we performed RNA-seq analysis of colorectal carcinoma cell line HCT116 (p53+/+ and p53 -/-), breast carcinoma line MCF7, and osteosarcoma line SJSA treated with MDM2 inhibitor Nutlin.
Project description:Hypothesis: Based on gene chip results and further investigation, MDMX C463A/WT cells shows large portion of transcripts change at p53 dependent manner. As transcriptional factor, p53 regulates those genes could be related to DNA binding status change. ChIP-seq was used to test this hypothesis and figure out global map of p53 binding in MCF7 C463A/WT MCF7 cells by using MCF7 parental cells as reference.
Project description:Treatment of MCF7 breast cancer cells by cisplatin leads to a very specific metabolic response and an onset of cell death about 10-11 h after beginning of treatment. For more detailed understanding of the molecular processes underlying the specific metabolic response, mRNA was isolated from MCF7 cells when the specific changes, (i) induction of glycolysis and (ii) onset of cell death, were detected during online measurement in the cell biosensor system. MCF7 breast cancer cells were treated with cisplatin in the BIONAS 2500 cell biosensor chip system, and samples were collected from the biosensor chip module at time points when glycolysis was induced (change of ph; 8-9h) and at the beginning of cell death (change of impedance; 10-11h).
Project description:The RB and p53 tumor suppressor pathways regulate the transcription of genes involved in cell cycle progression, DNA replication, DNA repair, and apoptosis. These tumor suppressors are critical modulators of the response to genotoxic damage and both pathways are frequently inactivated in human cancers. We used microarrays to monitor gene expression patterns upon exposure to cisplatin treatment in fibroblasts harboring loss/inactivation of RB and/or p53. We generated mouse adult fibroblasts harboring loss/inactivation of RB and/or p53 and subjected these cell populations to cisplatin treatment for 24 hours. Treated cell populations were allowed to recover from cisplatin exposure, generating a recurred cell popuation. Untreated and recurred cell populations were then subjected to RNA extraction and hybridization on Affymetrix microarrays.
Project description:Background: Cisplatin-based chemotherapy is the first-line treatment for patients with advanced bladder cancer (BC). However, the development of cisplatin resistance limits its antitumor effects. While, the mechanism of cisplatin resistance remains unclear. Methods: Bioinformatics techniques were used to analyze genes and pathways associated with cisplatin therapy resistance. A variety of biological techniques were used to identify the role of ITGB4 in cisplatin sensitivity in BC and its potential molecular mechanism. Results: In this study, we demonstrated that ITGB4 plays a key role in regulating the sensitivity of p53 wild-type (WT) BC to cisplatin therapy. Our findings revealed that ITGB4 reduces the sensitivity of BC to cisplatin by inhibiting phosphorylation of the p53-S15 site and promoting MDM2 binding to p53, thereby reducing p53 expression. Additionally, we showed that ITGB4 influences the antitumor effects of MDM2 inhibitors when they are combined with cisplatin therapy. Furthermore, we found that ITGB4 levels were elevated in cisplatin-resistant BC cells, a process mediated by STAT3 activation. The combination of STAT3 inhibitors can enhance the antitumor effect of cisplatin in BC. Conclusions: ITGB4 is a key molecule influencing cisplatin sensitivity in p53 WT BC, and the combination of STAT3 inhibitors can enhance the antitumor effect of cisplatin.
