KIF15 and colorectal carcinoma: To assess whether ERK signaling is key for B7-H3/KIF15 axis-mediated radioresistance in CRC cells, colony formation, cell viability, cell apoptosis and Western blot assays were performed in B7-H3-overexpressing CRC cells treated with PD98059, an ERK inhibitor, plus 4 Gy X-ray radiation.