MCL1 and lung cancer: Importantly, we have recently discovered that the cigarette smoke components, nicotine and NNK, can induce phosphorylation of Bcl2, Mcl-1, Bax, and Bad, which leads to activation of Bcl2 and Mcl-1 [5, 23] and inactivation of Bax and Bad in association with increased chemoresistance in human lung cancer cells [24, 25].