High cytoplasmic YAP1 expression predicts a poor prognosis in patients with colorectal cancer.

Purpose. Yes associated protein 1 (YAP1), which is a standout amongst the most essential effectors of the Hippo pathway, assumes a vital part in a few kinds of cancer. However, whether YAP1 is an oncogene in CRC (colorectal cancer) remains controversial, and the association between the subcellular localization of YAP1 and clinical implications in CRC remains unknown. Patients and methods. In this study, we investigated the subcellular localization of YAP1 in CRC cells by immunohistochemistry and then associate these findings with clinical information in a large CRC cohort with 919 CRC patients. Results. The results show that CRC tissues has a significant higher expression of cytoplasmic YAP1 compared to adjacent normal tissues (all P < 0.001). Cytoplasmic YAP1 expression was significantly associated with the number of lymph nodes removed and differentiation grade (all P < 0.001). Furthermore, after correcting confounding variables, for example, TNM stage and differentiation grade, the multivariate Cox analysis confirmed cytoplasmic YAP1-high subgroup had a significant shorter DFS (HR = 3.255; 95% CI [2.290-4.627]; P < 0.001) and DSS (HR = 4.049; 95% CI [2.400-6.830]; P < 0.001) than cytoplasmic YAP1-low subgroup. High cytoplasmic YAP1 expression is associated with a worse survival in stage III CRC patients who received chemotherapy. Conclusion. Cytoplasmic YAP1 could be could be utilized as a prognosis factor in CRC patients, and may be an indicator of whether certain patients population could benefit from postoperative chemotherapy.