MCL1 and lung cancer: Specifically, USP13 and MCL1 expression was both observed in 93.3% (28 of 30) of our lung cancer cohort, whereas only 26.7% (8 of 30) and 3.3% (1 of 30) of normal lung tissues displayed positive staining of USP13 and MCL1, respectively (Fig. 2d, e).