MCL1 and non-small cell lung carcinoma: More important, metformin can inhibit the expression of anti-apoptotic proteins such as Bcl-2 and Mcl-1 [23], In the present study, and as expected, metformin could effectively overcome the deficiency of vorinostat in regulating anti-apoptotic Bcl-2 family proteins, the addition of low-dose metformin could significantly inhibit Bcl-2, Bcl-xL and Mcl-1, and further enhanced the expression levels of BIM and BAX, and synergistically induced apoptosis and enhanced the sensitivity of gefitinib in these NSCLC cells.