CDK4 and acral lentiginous melanoma: Genomic profiling also identified frequent gene amplifications in available acral melanoma subjects (n = 7) in the study, including cell cycle regulators (Cyclin D1, CDK4, or CDK6) (5 out of 7), and genes locating in 11q13 such as fibroblast growth factors (FGF19, FGF3, and FGF4) and EMSY (a BRCA2 inactivating gene) (3 out of 7) (Fig. 7).