Our results demonstrated that the drug combination significantly and synergistically decreased cell viability at relatively low concentrations in ALK-positive H3122 and H2228 cells, due to G1 cell cycle arrest and increased apoptosis....To characterise the effect of alectinib, SHP099, and the combination of alectinib/SHP099 on apoptosis in H3122 and H2228 cells were used....Cleaved caspase-3 expression—a marker of the apoptosis cascade—was also distinctly increased...to a 10.6-fold and 2.3-fold increase for the combination compared to the control for H3122 and H2228 cells respectively (p < 0.05, Figs. 6D, 7D).