For example, inactivation of MEK5/ERK5 signaling pathway may reduce the expression of c-myc in CRC cells and finally supress cell proliferation, colony formation and cell invasion of CRC.21 A recent research also suggests that ERK5 signaling rescues intestinal epithelial turnover and tumor cell proliferation upon ERK1/2 abrogation, while a combination of MEK1/2 and ERK5 inhibitors show a more remarkable effect in inhibiting CRC cell growth.22 The gene discussed is MAP2K5; the disease is colorectal carcinoma.