PROS1 and melanoma: Moreover, the vem + pic group showed the weakest expression of myeloid leukemia 1 (MCL‐1) (Figure 4Ci), an antiapoptotic protein of B‐cell lymphoma 2 (BCL‐2) family involved in tumorigenesis, poor prognosis, and drug resistance by binding to the pro‐apoptotic BCL‐2 proteins.[28] The expression of Ki‐67, a representative marker of cancer cell proliferation, was also significantly reduced in the vem + pic group, indicating the diminished proliferation of melanoma cells in the group (Figure 4Cii).