Project description:CEACAM family proteins have been extensively studied as cell adhesion molecules, yet the biological and clinical significance of CEACAM6 remains relatively unexplored. Our research identifies a significant increase in CEACAM6 expression in lung adenocarcinoma, particularly correlating with EGFR mutation status. In EGFR-mutated lung cancer cells, CEACAM6 knockdown induced apoptosis and reduced p-ERK1/2 signaling downstream of EGFR. Treatment with EGFR-tyrosine kinase inhibitors (TKIs) decreased CEACAM6 levels, leading to TKI-resistant lung cancer cells that exhibited reduced p-ERK1/2 and increased epithelial-mesenchymal transition (EMT) characteristics. Co-immunoprecipitation assays revealed an interaction between CEACAM6 and EGFR. Although CEACAM6 expression was lost in EGFR-TKI resistant cells, its re-expression stabilized EGFR and increased sensitivity to EGFR-TKIs. TGF-? treatment, which induced EMT, also decreased CEACAM6 expression and improved EGFR-TKI resistance. Further analysis showed that EGFR-TKI resistant lung cancer cells had lower H3K27ac epigenetic modification levels at the CEACAM6 locus than EGFR-TKI sensitive cells. Treatment with HDAC1/2 inhibitors in EGFR-TKI sensitive cells reduced CEACAM6 expression, induced EMT and TGF-?-ligand/receptor gene expression, and enhanced EGFR-TKI resistance. These data highlight the crucial role of CEACAM6 in maintaining oncogenic EGFR signaling and its regulation by cytokine stimulation and epigenetic modification, influencing EGFR-TKI sensitivity. Our findings underscore CEACAM6's potential as a valuable biomarker in EGFR-driven lung adenocarcinoma and its intricate involvement in EGFR-related pathways.
Project description:Whole exome sequencing was performed on set of 48 DNA samples obtained from 16 EGFR mutated NSCLC patients whose tumors progressed following EGFR-TKI treatment. The DNA samples included baseline biopsy, rebiopsy and blood from the same patient. By comparing the variants in rebiopsy tumors and baseline tumors we aim to understand the genomic alterations responsible for the development of EGFR-TKI resistance in NSCLC patients.
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: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.
Project description:Previous study has demonstrated that HCC827/gef cells are resistant to gefitinib-induced aspoptosis. To investigate the regulators contributed to gefitinib resistance in lung cancer, we analyzed the gene expression profiles between HCC827 andHCC827/gef cells. Reduced IGFBP7 in TKI-resistant cells reversed resistance to EGFR-TKIs, and increased EGFR-TKI-induced apoptosis through up-regulation of BIM and activation of caspases. Suppression of IGFBP7 attenuated phosphorylation of IGF-IR and downstream AKT in TKI-resistant cells.
