Expression and clinical significance of circulating microRNA-375 and tissue Yes-associated protein 1 in colorectal cancer patients

Objective To explore the relationship between circle microRNA (miRNA, miR)-375 and tissue Yes-associated protein 1 (YAP1) expression in patients with colorectal cancer, as well as their relationship with clinicopathological characteristics of colorectal cancer. Methods Eighty-seven patients with colorectal cancer were selected as the study group, and 80 healthy volunteers served as the control group. The circle miR-375 expression in both groups was detected by quantitative polymerase chain reaction (PCR). The YAP1 expression in both cancer tissue and adjacent healthy tissue was detected by immunohistochemistry. The relationship between the two indexes and clinicopathological characteristics and prognosis was analyzed. The patients in the study group were divided into 3 groups according to miR-375 and YAP1 expression: Lower miR-375 and higher YAP1 (group A, n=21), both lower miR-375 and YAP1, or both higher miR-375 and YAP1 (group B, n=32), and higher miR-375 and lower YAP1 (group C, n=34). The relationship between the two indexes andprognosis was analyzed. Results The circle miR-375 expression in case group (0.132±0.085) was significantly lower than that in the control group (0.521±0.186), and the expression level of YAP1 in cancer tissues (2.201±0.856) was significantly higher than that in healthy tissues (0.814±0.262) (t=51.826, 51.175, P<0.05). There was a linear negative correlation between miR-375 and YAP1 expression (r=-0.691, P<0.05), and the interaction between them was confirmed in double luciferase assay report (t=9.564, P<0.05). The expression of both miR-375 and YAP1 was related to Dukes stage, and the miR-375 expression in patients with colorectal cancer of stage C was significantly lower than that in stage A and stage B, and the YAP1 expression in stage C was significantly higher than that in stage A and stage B (F=4.347, 3.724, P<0.05). The detection of miR-375 combined with YAP1 showed good predictive value for recurrence/metastasis and death of colorectal cancer (AUC=0.739, 0.699, P<0.05). The patients in group A got the shortest median survival time, while the patients in group C got the longest median survival time, and the difference between groups had statistical significance (χ2=4.685, P<0.05). Conclusion There is an interaction between mir-375 and YAP1, and both of them are involved in the occurrence and development of colorectal cancer. Key words: Colorectal cancer; MicroRNA-375; Yes-associated protein 1; Hippo signaling; Prognosis