YAP1 and adenocarcinoma: On-target and off-target resistance mechanisms are among the many mechanisms of developed resistance that have been identified.7 The most recent study demonstrated that Yes-associated protein-1 (YAP-1) expression in NSCLC adenocarcinomas is a potential drug resistance mechanism and inhibiting their co-transcriptional factor can restore the cell’s sensitivity to EGFR inhibitors, including OSI.