When this approach confirmed that epithelial‐to‐mesenchymal transition (EMT)‐related proteins correlated significantly with Plk1 inhibitor sensitivity, we used isogenic pairs of epithelial NSCLC cell lines treated with TGF‐β to induce a mesenchymal phenotype to measure the changes in protein expression and activation after Plk1 inhibition. Here, TGFB1 is linked to non-small cell lung carcinoma.