YAP1 expression in colorectal cancer confers the aggressive phenotypes via its target genes

Yes-associated protein1 (YAP1), a downstream effector of the Hippo pathway, is over-expressed in several types of malignancies. We analyzed retrospectively the TCGA database using 447 colorectal cancer (CRC) samples to determine the correlation between YAP1 expression level and CRC patient prognosis. YAP1-enforced expressed CRC cell lines were constructed using the lentivirus particles containing a YAP1 insert. YAP1 was highly expressed in CRC cancerous tissues and is associated with distant metastasis of CRC patients. Kaplan - Meier analysis indicated that CRC patients with a higher YAP1 expression group (n = 104) had worse disease-free survival (DFS) and overall survival (OS) than lower YAP1 expression group (n = 343) (p = 0.008 and p = 0.022). Univariate and multivariate analysis indicated that the elevated YAP1 expression predicted the aggressive phenotype and was an independent indicator for OS and DFS of CRC patients. YAP1 over-expression in CRC cells enhanced their migration and invasion significantly which can be reversed by AXL, CTGF, or CYR61 interference. The study suggested that YAP1 affected the prognosis of CRC patients and controlled the abilities of invasion and migration of CRC cells via its target genes AXL, CTGF, and CYR61.