The combination of the mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2 inhibitor, selumetinib, and the histone deacetylase inhibitor, vorinostat exerts potent antitumor effects on in vitro models of colorectal cancer, including synergistic inhibition of cell proliferation and migration, G1 cell-cycle arrest, induction of apoptosis, and spheroid formation in 3D culture 54. Here, MAPK3 is linked to colorectal cancer.