The prognostic relevance of cyclin-dependent kinase inhibitor 2 A (CDKN2A) mRNA expression data was derived from The Cancer Genome Atlas (TCGA) data.<h4>Results</h4>Ribociclib demonstrates significant antitumoral effects in various CRC, HCC, and BC cell lines, similar to two other approved CDK4/6 inhibitors (palbociclib and abemaciclib). Here, CDKN2A is linked to breast cancer.