Expression And Clinical Significance Of Hippo Pathway In Colorectal Cancer

Objective:This study aimed to investigate the expression and its clinical significance of Hippo pathway components in the progression and metastasis of colorectal cancer (CRC).Materials and Methods:Quantitative real-time polymerase chain reaction (qRT-PCR) was used to examine the mRNA expression levels of MST1, LATS2, YAP, TAZ, TEAD1, CDX2, and OCT4, and western blot (WB) was used to examine the protein expression levels of MST1, YAP, TEAD1, and CDX2in30specimens of human colorectal adenomas,50pairs of human CRC tissues, and adjacent nontumorous tissues from CRC patients. Glyceraldehyde3-phosphate dehydrogenase (GAPDH) was used as the housekeeping gene in qRT-PCR.Results:The mRNA expression levels of MST1and LATS2showed an increasing tendency from CRC to adjacent nontumorous tissues (P<0.001). Conversely, the mRNA expression levels of YAP, TAZ, TEAD, and OCT4showed a decreasing tendency from CRC to adjacent nontumorous tissues (P<0.001). MST1protein was downregulated and YAP and TEAD1proteins were upregulated in CRC (all P<0.001). The mRNA and protein expression levels of CDX2in CRC were significantly lower than those in colorectal adenomas and adjacent nontumorous tissues (P<0.001), but there was no significant difference between the latter two groups (qRT-PCR, P=0.113; WB, P=0.151). Furthermore, statistical analysis showed that the expression levels of Hippo signal pathway components were associated with tumor differentiation, lymph node metastasis, and TNM stage.Conclusion:Hippo pathway is suppressed in the progression from colorectal adenomas to CRC and is associated with CRC progression and metastasis. This study suggests the components of Hippo pathway might be prognostic indicators for CRC patients.