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:14-3-3ζ has been found to promote the proliferation, metastasis and chemoresistance of cancer cells in several cancers including lung adenocarcinoma; however, its significance in epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) resistance remains unknown. Our work uncovers a hitherto unappreciated role of 14-3-3ζ in EGFR-TKI resistance. We determined global gene expression profiling in EGFR-TKI-resistant H1975 cells using microarray analysis.
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:EGFR tyrosine kinase inhibitors (EGFR TKIs) are the standard of care treatment for patients with EGFR-mutant lung adenocarcinoma (LUAD). Although initially effective, EGFR TKIs are not curative. Disease inevitably relapses due to acquired drug resistance. Here, we tested the ability of 1,25(OH)2D3 to promote epithelial differentiation and restore EGFR TKI sensitivity in models of EGFR TKI resistance that were associated with epithelial–mesenchymal transition (EMT).
Project description:Noncoding RNAs play important roles in various biological processes and diseases, including cancer. Expression profile of circular RNAs (circRNA) is largely unknown in lung adenocarcinoma. This study is designed to explore mRNA, long noncoding RNA (lncRNA), and circRNA in lung adenocarcinoma.
Project description:The model is based on publication:
Mathematical analysis of gefitinib resistance of lung adenocarcinoma caused by MET amplification
Abstract:
Gefitinib, one of the tyrosine kinase inhibitors of epidermal growth factor receptor (EGFR), is effective for treating lung adenocarcinoma harboring EGFR mutation; but later, most cases acquire a resistance to gefitinib. One of the mechanisms conferring gefitinib resistance to lung adenocarcinoma is the amplification of the MET gene, which is observed in 5–22% of gefitinib-resistant tumors. A previous study suggested that MET amplification could cause gefitinib resistance by driving ErbB3-dependent activation of the PI3K pathway. In this study, we built a mathematical model of gefitinib resistance caused by MET amplification using lung adenocarcinoma HCC827-GR (gefitinib resistant) cells. The molecular reactions involved in gefitinib resistance consisted of dimerization and phosphorylation of three molecules, EGFR, ErbB3, and MET were described by a series of ordinary differential equations. To perform a computer simulation, we quantified each molecule on the cell surface using flow cytometry and estimated unknown parameters by dimensional analysis. Our simulation showed that the number of active ErbB3 molecules is around a hundred-fold smaller than that of active MET molecules. Limited contribution of ErbB3 in gefitinib resistance by MET amplification is also demonstrated using HCC827-GR cells in culture experiments. Our mathematical model provides a quantitative understanding of the molecular reactions underlying drug resistance.
Project description:Intrinsic and acquired resistance represent major obstacles to optimize outcomes in epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) targeted therapy in lung adenocarcinoma (LUAD). Hence, a deeper understanding of EGFR-TKI resistance mechanisms in LUAD will potentially assist in formulating strategies to delay or overcome such resistance. Herein, it was observed that trefoil factor 3 (TFF3) is a crucial mediator of the LUAD EGFR-TKI response. TFF3 conferred intrinsic resistance to EGFR inhibition in LUAD by promotion of EGFR activation. TFF3 expression was also increased in acquired EGFR-TKI resistant LUAD, accompanied by reduced EGFR activation. YAP, a key mediator of the Hippo signaling, was positively regulated by TFF3 by post-transcriptional mechanisms and was responsible for acquired EGFR-TKI resistance mediated by TFF3. Inhibition of TFF3 by a small molecule inhibitor not only enhanced EGFR-TKI sensitivity in LUAD cells but also restored the sensitivity of acquired EGFR-TKI resistant LUAD cells to EGFR-TKIs in vitro and in vivo. These findings demonstrate a pivotal function of TFF3 in mediating EGFR-TKI resistance in LUAD and may offer a potential therapeutic mechanism for delaying or overcoming resistance to EGFR-TKIs.
Project description:Lung adenocarcinoma (LUAD) is the most common type of lung cancer. Resistance to osimertinib, a 3rd generation EGFR-TKI, develops within 12 months in patients with EGFR T790M mutation. This study used RNA-seq to identify circular RNAs (circRNAs) regulating osimertinib resistance in LUAD. We identified circSPINT2 as downregulated in osimertinib-resistant cell lines (OR3, OR4, OR6, HOsR) compared to parental H1975 cells. circSPINT2 enhances osimertinib sensitivity by inducing apoptosis via the hsa-miR-1296-3p/RBP1 axis. circSPINT2 is proposed as a non-invasive biomarker for monitoring osimertinib resistance in LUAD.
Project description:Through the study of EGFR-mutant lung adenocarcinoma we show that NFkB signaling is rapidly engaged by EGFR oncogene inhibition to promote tumor cell persistence and therapy resistance. Unexpectedly, we found that EGFR oncogene inhibition induced an EGFR-TRAF2-RIP1-IKK complex that stimulated an NFkB-mediated transcriptional survival program. We identified a direct pharmacologic NFkB inhibitor, PBS-1086, that suppressed this adaptive survival program and increased both the magnitude and duration of initial EGFR TKI response in cellular and in vivo tumor models, including a novel patient-derived NSCLC xenograft. These findings unveil NFkB as a critical adaptive survival mechanism engaged in response to EGFR oncogene inhibition and identify PBS-1086 as a promising NFkB inhibitor to eliminate disease persistence and potentially prevent the emergence of resistance in patients. RNAseq analysis of 11-18 (EGFR-mutant lung adenocarcinoma) cells in the context of drug treatment with erlotinib and/or genetic or pharmacological inactivation of NFkB