P-0032 Overexpression of Yes-Associated Protein 1 Contributes to the Progression and Poor Prognosis of Gastric Carcinomas

Abstract

IntroductionYes-associated protein 1 (YAP1) has been shown to be a candidate oncogene and identified that it could induce the transcription of many genes. This study aimed to explore the clinicopathologic significance and correlations with carcinogenesis, metastasis and prognosis of gastric carcinoma. MethodsThe immunohistochemical method was used to detect YAP1, ki67 and c-myc expressions in gastric carcinoma and its precancerous lesions and analyze the correlations of protein expressions with clinicopathologic significance and prognosis of gastric carcinoma. ResultsThe positive rate of YAP1 expression in gastric carcinoma was significantly higher than that in normal gastric mucosa (19.2%, 32/167), chronic atrophic gastritis (25.0%, 10/40) and intestinal metaplasia (39.7%, 29/73), respectively (P<0.05). In gastric cancer with lymph node metastasis, the positive rate of YAP1 (72.8%, 115/158) was significantly higher than that in the group without lymph node metastasis (57.1%, 32/56), (P<0.05). The expression of YAP1 protein was statistically correlated with the expression of c-myc and ki67 proteins, respectively, rk=0.347; 0.204, P<0.05. Patients with YAP1 positive tumors tended to have poorer prognosis than those with negative tumors (P=0.004). Multivariate cox proportional hazards regression of 191 patients with gastric carcinoma indicated that YAP1 overexpression (P=0.043, hazard ratio [HR] 1.676), invasion depth (P=0.003 HR 1.543) and lymph node metastasis (P<0.001, HR 3.080) were high hazard factors for gastric carcinoma. ConclusionYAP1 overexpression was related to the progression and poor prognosis of gastric carcinoma and YAP1 may promote lymph node metastasis, as an adjuvant factor for predicting lymph node metastasis of gastric cancer.