SRC Family Kinase Inhibition Targets YES1 and YAP1 as Primary Drivers of Lung Cancer and as Mediators of Acquired Resistance to ALK and Epidermal Growth Factor Receptor Inhibitors.

Abstract

The identification of novel oncogenic driver alterations and novel mechanisms of acquired resistance (AR) is the key for further development of personalized therapy. The current study investigates the potential role of <i>YES1</i> amplification as a primary driver of tumorigenesis and of <i>YES1/YAP1</i> amplifications as mediators of AR to ALK and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). Models of ectopic expression were established and characterized for YES1 and YAP1 in human bronchial epithelial cells and <i>ALK</i> fusion-positive (ALK+) and <i>EGFR</i>-mutant lung adenocarcinoma cell lines. MSK-IMPACT data for all lung adenocarcinoma cases and for ALK and EGFR TKI AR cases were surveyed for <i>YES1</i> and <i>YAP1</i> amplification. We report response to SRC family kinase (SFK) inhibition in a patient whose lung cancer exhibited <i>YES1</i> amplification, without any well-established primary driver alteration, suggesting that <i>YES1</i> amplification can also function as a primary oncogenic driver. To investigate the possibility of <i>YES1</i> as a primary driver in tumorigenesis, we established preclinical models of YES1 overexpression using human bronchial epithelial cells and normal human breast epithelial cells. We showed that YES1 overexpression conferred sensitivity to SFK TKIs and promoted EGF-independent growth in a YAP1-dependent manner. Analysis of clinical genomic sequencing data from cases of AR to EGFR and ALK inhibitors revealed acquired amplification of <i>YAP1</i> in four cases. <i>EGFR</i>-mutant and <i>ALK</i> fusion-positive cells overexpressing YES1 or YAP1 were resistant to EGFR and ALK TKIs, respectively, but were sensitive to dual inhibition of the primary driver and YES1. Our results demonstrate the therapeutic potential of SFK inhibition in primary tumorigenesis and AR driven by YES1/YAP1 signaling.