(A and B) Suppression of MED12, but not of other MEDIATOR components CDK8 or MED13, leads to strong induction of TGF-βR2 and elevated levels of p-SMAD2. Western blotting analysis of PC9 (A) and H3122 (B) cells expressing pLKO or shRNAs targeting MED12 CDK8 or MED13 is shown.
(C and D) MED12KD, but not knockdown of CDK8 or MED13, confers resistance to TKIs. (C) PC9 cells expressing pLKO or independent shRNAs targeting MED12 CDK8 or MED13 were cultured in 50 nM gefitinib. The cells were fixed, stained, and photographed after 10 (untreated) or 21 days (treated). (D) H3122 cells expressing pLKO or independent shRNAs targeting MED12, CDK8, or MED13 were cultured in 300 nM crizotinib. The cells were fixed, stained, and photographed after 14 (untreated) or 28 days (treated).