CDK1 and melanoma: Western blot assays showed that the G1 phase marker cyclin D1 was downregulated, S phase markers CDK2 and cyclin E1 were increased, and G2/M phase markers CDK1 and cyclin B1 were downregulated after knockdown of CENPF (Figure 5B), which indicated that melanoma cells transitioned more slowly to G2/M phase, with some being arrested in the G2/M phase.