Project description:Activating mutations of EGFR have been characterized as important mechanisms for carcinogenesis in a subset of EGFR-dependent non-small cell lung cancers (NSCLC). EGFR tyrosine kinase inhibitors (TKI), such as erlotinib and gefitinib, have dramatic clinical effects on EGFR-addicted lung cancers and are used as first-line therapy for EGFR-mutant tumors. However, eventually all tumors acquire secondary resistance to the drugs and progress. We established a model to better understand mechanisms of acquired resistance. NCI- HCC827 cells are EGFR-mutant and highly erlotinib-sensitive. In this study we exposed HCC827 cells to increasing concentrations of erlotinib and two highly erlotinib-resistant subclones were developed (ER3 and T15-2). In these subclones no acquired alterations of EGFR or MET were found. We hereby performed a gene expression microarray studies to understand changes that might explain mechanisms of resistance. Through these studies we demonstrated in one resistant clone (ER3) overexpression of AXL, a tyrosine kinase implicated in imatinib and lapatinib resistance. Gene expression profilings were measured in NSCLC cell line HCC827 and two erlotinib-resistant HCC827-originated sublines ER3 and T15-2.
Project description:EGFR tyrosine kinase inhibitors (TKIs) have demonstrated tremendous clinical benefits in non-small cell lung cancer (NSCLC) patients. However, resistance emerges rapidly due to a variety of mechanisms including a secondary mutation of T790M in EGFR that abrogates the binding of the drugs. It has been postulated that EGFR TKIs, such as afatinib (BIBW2992), with activity against the T790M mutant EGFR kinase might overcome the drug resistance problem or, when used as the first-line treatment, delay or suppress the emergence of resistance in EGFR. In this study, we generated BIBW2992-resistant cells, HCC827-BR1 and HCC827-BR2, from the parental HCC827 cells. In HCC827-BR cells, EGFR, MET, and Erb2 were down-regulated and no secondary mutation was found to be present in the coding region of EGFR. Gene set enrichment analysis (GSEA) revealed an obvious signature of epithelial to mesenchymal transition (EMT) in the drug resistant cells. Subsequently, the HCC827-BR cells were shown to be more invasive. Most importantly, we strived to seek if alternative medicine might be applied alone or in combination to treat the BIBW2992-resistant cells or to, under BIBW2992 treatment, diminish the emergence of resistant cells. Compared to the parental cells, the HCC827-BR cells were more sensitive to dasatinib, an FDA-approved kinase inhibitor. Furthermore, as revealed in the clonogenicity assay, the reduction of tumor-colony-forming cells after exposure to BIBW2992 was substantially potentiated by low concentration of dasatinib. Thus, prospective clinical investigations may be needed to evaluate if dasatinib can be beneficial to patients receiving second-generation EGFR TKIs for the treatment of NSCLC. Over a period of 3-4 months, BIBW2992-resistant cells were isolated in cell culture by maintenance of HCC827 cells in the presence of escalating concentrations of BIBW2992 up to 2 μM. Two cell lines, HCC827-BR1 and HCC827-BR2, were established based on individual clones. Total RNA of these HCC827, HCC827-BR1 and HCC827-BR2, were extracted for gene expression microarray analysis using Illumina HumanHT12 v3 BeadChip.
Project description:EGFR tyrosine kinase inhibitors (TKIs) have demonstrated tremendous clinical benefits in non-small cell lung cancer (NSCLC) patients. However, resistance emerges rapidly due to a variety of mechanisms including a secondary mutation of T790M in EGFR that abrogates the binding of the drugs. It has been postulated that EGFR TKIs, such as afatinib (BIBW2992), with activity against the T790M mutant EGFR kinase might overcome the drug resistance problem or, when used as the first-line treatment, delay or suppress the emergence of resistance in EGFR. In this study, we generated BIBW2992-resistant cells, HCC827-BR1 and HCC827-BR2, from the parental HCC827 cells. In HCC827-BR cells, EGFR, MET, and Erb2 were down-regulated and no secondary mutation was found to be present in the coding region of EGFR. Gene set enrichment analysis (GSEA) revealed an obvious signature of epithelial to mesenchymal transition (EMT) in the drug resistant cells. Subsequently, the HCC827-BR cells were shown to be more invasive. Most importantly, we strived to seek if alternative medicine might be applied alone or in combination to treat the BIBW2992-resistant cells or to, under BIBW2992 treatment, diminish the emergence of resistant cells. Compared to the parental cells, the HCC827-BR cells were more sensitive to dasatinib, an FDA-approved kinase inhibitor. Furthermore, as revealed in the clonogenicity assay, the reduction of tumor-colony-forming cells after exposure to BIBW2992 was substantially potentiated by low concentration of dasatinib. Thus, prospective clinical investigations may be needed to evaluate if dasatinib can be beneficial to patients receiving second-generation EGFR TKIs for the treatment of NSCLC.
Project description:Activating mutations of EGFR have been characterized as important mechanisms for carcinogenesis in a subset of EGFR-dependent non-small cell lung cancers (NSCLC). EGFR tyrosine kinase inhibitors (TKI), such as erlotinib and gefitinib, have dramatic clinical effects on EGFR-addicted lung cancers and are used as first-line therapy for EGFR-mutant tumors. However, eventually all tumors acquire secondary resistance to the drugs and progress. We established a model to better understand mechanisms of acquired resistance. NCI- HCC827 cells are EGFR-mutant and highly erlotinib-sensitive. In this study we exposed HCC827 cells to increasing concentrations of erlotinib and two highly erlotinib-resistant subclones were developed (ER3 and T15-2). In these subclones no acquired alterations of EGFR or MET were found. We hereby performed a gene expression microarray studies to understand changes that might explain mechanisms of resistance. Through these studies we demonstrated in one resistant clone (ER3) overexpression of AXL, a tyrosine kinase implicated in imatinib and lapatinib resistance.
Project description:The non-small cell lung carcinoma (NSCLC) HCC827 cell line is an established preclinical model for tyrosine kinase inhibitors. To be able to better understand the differences in response between individual cells, we performed treatment of HCC827 cells grown in cell culture with erlotinib followed by Drop-seq. We were able to clearly distinguish cells that were treated with the drug from untreated cells, and we discovered different cell populations within the treated cells, likely reflecting heterogeneity of drug resistant cells. We were able to identify specific biomarkers, as preferentially expressed genes, for each cell population. The results of our study will address preexisting and acquired drug resistance that limits clinical usefulness of targeted strategies, particularly in NSCLC.
Project description:The non-small cell lung cancer (NSCLC) cell line HCC827 harbors an activating EGFR mutation (exon 19 deletion) that confers sensitivity to the FDA-approved EGFR inhibitor erlotinib. By applying the ClonTracer barcoding system, we were able to show the presence of pre-existing sub-populations in HCC827 that contribute to erlotinib resistance. Prior studies implicated that MET amplification confers resistance to erlotinib in this cell line. Therefore we examined the effects of the c-Met inhibitor crizotinib on the barcoded HCC827 population when treated either sequentially or simultaneously with both inhibitors. Despite the significant reduction in barcode complexity, the erlotinib/crizotinib combination treatment failed to eradicate all of the resistant clones implying the presence of an erlotinib/crizotinib dual resistant subpopulation. We performed transcriptome profiling (RNA-seq) to elucidate the potential resistance mechanisms of the dual resistant subpopulation in comparison to vehicle-treated or single agent erlotinib-resistant HCC827 cell populations as controls. mRNA profiling of the subpopulations of human NSCLC cell line HCC827 that contribute to EGFR inhibitor erlotinib and MET inhibitor crizotinib resistance
Project description:The non-small cell lung cancer (NSCLC) cell line HCC827 harbors an activating EGFR mutation (exon 19 deletion) that confers sensitivity to the FDA-approved EGFR inhibitor erlotinib. By applying the ClonTracer barcoding system, we were able to show the presence of pre-existing sub-populations in HCC827 that contribute to erlotinib resistance. Prior studies implicated that MET amplification confers resistance to erlotinib in this cell line. Therefore we examined the effects of the c-Met inhibitor crizotinib on the barcoded HCC827 population when treated either sequentially or simultaneously with both inhibitors. Despite the significant reduction in barcode complexity, the erlotinib/crizotinib combination treatment failed to eradicate all of the resistant clones implying the presence of an erlotinib/crizotinib dual resistant subpopulation. We performed transcriptome profiling (RNA-seq) to elucidate the potential resistance mechanisms of the dual resistant subpopulation in comparison to vehicle-treated or single agent erlotinib-resistant HCC827 cell populations as controls.
Project description:Lung adenocarcinoma cells harboring epidermal growth factor receptor (EGFR) mutations are sensitive to EGFR tyrosine kinase inhibitors (TKIs). Prolonged cancer treatment will induce the development of acquired resistance to EGFR TKI. To gain insight into the molecular mechanisms of EGFR-TKIs resistance, we generate EGFR-TKI-resistant HCC827-8-1 cells to be analyzed by microarray with their parental HCC827cells. gefitinib resistant HCC827-8-1 cells with three replications; gefitinib-sensitive HCC827 cells with three replications
Project description:To investigate the abnormal gene expression in Osimertinib Resistance lung cancer cell line, We performed gene expression profiling analysis using data obtained from RNA-seq of HCC827 cell line and HCC827OR cell line.