Then, the cells were withdrawn from the etoposide for four days, allowing the cellular senescence phenotype (Figure 2A) and (ii) therapy-induced senescence (TIS): MSCs were treated for six days with palbociclib, a selective inhibitor of cyclin-dependent kinase 4 and 6 (CDK4/6) used to induce cell cycle arrest and the cellular senescence phenotype in cancer cells [24] (Figure 2A). The gene discussed is CDK4; the disease is cancer.