MAP2K5 and colorectal carcinoma: In 5 of 8 (62.5 %) CRC patients, the total MEK5 protein was up-regulated in tumor tissues compared with their adjacent nontumor colorectal mucosa; furthermore, the ratio of MEK5α to MEKβ was higher in all of the CRC tissues than in their adjacent normal colorectal mucosa (Fig. 2).