Aberrant activity of cyclin D–CDK4/6 pathway has been described in many types of cancer and it invariably leads to uncontrolled cell proliferation with rapid progression through the cell cycle [4–6]. Because of their key role in the cell cycle regulation and implication in carcinogenesis, CDK4/6 inhibition represents an attractive intervention for cancer management as they prevent the phosphorylation of Rb leading to halting the cell cycle progression [7, 8]. The gene discussed is RB1; the disease is cancer.