Project description:We obtained small cell lung cancer specimens and normal lung specimens from patients who died of drug-resistant SCLC. The small lung cancer specimens include primary lesions and metastatic lesions. Next generation sequencing was performed to assess the expression of miRNA in drug-resistant small cell lung cancer.
Project description:The expression profiles of miRNAs in drug-resistant non-small cell lung cancer (NSCLC) cell lines were identified via next generation sequencing and the common dysregulated miRNAs in drug-resistant NSCLC cell lines were picked up for further analysis.
Project description:Epigenetic regulation is one of the important causes of drug resistance in NSCLC.EZH2 and G9a as epigenetic enzymes play an important role in drug resistance in lung cancer. To further investigate the mechanism of EZH2 and G9a mediating NSCLC drug resistance, we used ChIP-seq to compare the changes of H3K27me3 and H3K9me2, the catalytic substrates of EZH2 and G9a, in parental cells H1299 and cisplatin-resistant cells H1299/CDDP.
Project description:Lung adenocarcinoma cells harboring epidermal growth factor receptor (EGFR) mutations are sensitive to EGFR tyrosine kinase inhibitors (TKIs), including gefitinib. Acquired resistance to EGFR-TKIs develops after prolonged treatments. Known mechanisms for EGFR-TKI resistance, including KRAS mutation, HER2 mutation, EGFR T790M mutation and MET gene amplification did not observe in the resistant cells, PC9/gef. The study was prompt to explore effective strategies against resistance to EGFR-TKIs in PC9/gef cells. Here, we used label-free quantitative mass spectrometry to globally profile the basal phosphoproteome and proteome of a panel of TKI sensitive PC9, TKI resistant PC9/gef and TKI dose-dependent PC9/gef NSCLC cell lines. For phosphorylation level, we identified 5844 phosphorylation sites from 4612 phosphopeptides of 1548 proteins. For protein level, we identified 3835 proteins. Most of the quantitatively change is from phosphorylation whereas most of the protein level is unchanged. Among these big datasets, there is a phosphopattern of phosphopeptides presented up-regulated in resistant cells but no response to further gefitinib treatment; we proposed this group could regulate drug resistance. By motif analysis, these phosphopeptides mapped to the corresponding kinases, CK2, as the drug resistant kinase. Network analysis showed that CK2 directed interacting with 10 proteins. Among these proteins, we found that HMGA1 is the substrate protein to CK2. By biochemical evidence, we discovered that CK2 could regulate cell death in TKI-resistant cells. Furthermore, we found that HMGA1 for the first time could be the potential drug resistant target to reverse the drug resistance in PC9/gef cells. The results provide new insights into HMGA1 as the drug resistant target through the cellular signaling networks associated with the TKI-induced drug resistant NSCLCs.
Project description:To investigate the difference of miRNA expression between lung cancer cell A549 and its DDP-resistant cell strain A549/DDP, we have employed miRNA microarray expression to discover the difference expression of miRNAs of A549 cells and A549/DDP. We conducted RT-qPCR to examine the expression levels of top differential expressed miRNAs, namely, miR-197-5p, miR-4443, miR-642a-3p, miR-27b-3p and miR-100-5p, confirming low variability between two methods. The A549/DDP was established from A549 in our laboratory, by exposing A549 to gradually increasing DDP concentrations, until the final concentration at 1μg/ml. To avoid the influence of drug to the A549/DDP cells, they were cultured in a drug-free medium for at least two weeks before gene expression analysis. miRNA expression of A549 and A549/DDP was then analzyed.
Project description:To identify miRNAs involved in drug resistance of human breast cancer, a miRNA microarray was performed on 5 cases of drug resistant tissues and 5 cases of drug sensitive tissues.The expression levels of totally 2019 miRNAs in 5 pairs of matched, drug resistant and drug sensitive tissues were examined by microarray. There were 27 differentially expressed miRNAs between drug resistant and drug sensitive tissues were identified of which there were 11 significantly up-regulated while the other 16 were down-regulated in drug resistant tissues compared to drug sensitive tissues. It was found that miR-489 was one of the most downregulated miRNAs in drug resistant tissues.
Project description:To investigate the difference of miRNA expression between lung cancer cell A549 and its DDP-resistant cell strain A549/DDP, we have employed miRNA microarray expression to discover the difference expression of miRNAs of A549 cells and A549/DDP. We conducted RT-qPCR to examine the expression levels of top differential expressed miRNAs, namely, miR-197-5p, miR-4443, miR-642a-3p, miR-27b-3p and miR-100-5p, confirming low variability between two methods.
Project description:aCGH of human melanoma cell lines comparing parental (drug sensitve) vs isogenic drug resistant-derived subline Two condition experiment: two BRAF-V600E mutant cell lines (drug sensitive - parental baseline) vs two derived sublines after chronic exposure to the MEK inhibitor trametinib (drug resistant) are compared