A Research Study On Protein Arginine And C Met Are...

Specific aims: EGFR and c-Met are receptor tyrosine kinases (RTKs), and tyrosine kinase inhibitors (TKIs) against these receptors have been initially effective when prescribed to patients in combination with traditional chemotherapy or radiation. However, the overall efficacy of TKIs is limited due to the development of resistance as seen through clinical trials in NSCLC. Epithelial Mesenchymal Transition (EMT) is a process by which epithelial cells undergo phenotypic and morphological changes to acquire mesenchymal characteristics including increased motility and invasiveness. Currently, the role of EMT in TKI drug resistance is poorly understood. EMT results in loss of tight junction proteins such as E-cadherin and upregulation of transcriptional repressors of these proteins such as ZEB1. Recently, protein arginine methyl transferase 1 (PRMT1) has been shown to be an important regulator of EMT, cancer cell migration and metastasis. However, the role of PRMT1 in TKI resistance is n ot known. In this study, we propose to evaluate the role of EMT proteins in TKI resistance using H2170 and H358 cell lines (wild type EGFR) that were made resistant to an EGFR inhibitor, erlotinib and a c-Met inhibitor, SU11274 and a combination of both. H3255 cell line (with L858R EGFR mutation), and H1975 cell line with L858R and T790M EGFR mutations which we have made resistant to erlotinib will also be used. Our recent in vitro studies indicate that TKI resistance may be due to the activation