Besides, multiple cell-cycle and apoptosis-related genes (AURKB, BIRC5, MKI67, CDK2, etc.)also exhibit a high expression level in the C5 subpopulation, and cyclin-dependent kinase-2 (CDK2), which has been identified as a biological marker of melanoma, could be a potential therapeutic target in melanoma treatment. The gene discussed is MKI67; the disease is melanoma.