AR and lung carcinoma: A pioneering study using PC‐9 lung cancer cell lines treated with erlotinib revealed a small fraction of viable quiescent cells that survived drug treatment for 9 days, referred to as DTP, that resumed proliferation in continuous drug exposure for 33 days, referred to as DTEP.[8] In this study, we showed that no additional mutations occurred on AR mRNA in cells treated with inhibitors and that these cells do resist drugs and were phenotypically reversible.