Objective To explore the expression and clinical significance of Yes-associated protein 1 (YAP1) in esophageal squamous cell carcinoma.

Methods Immunohistochemical method was used to detect YAP1 expression in 439 cases of esophageal squamous cell carcinoma. The differences of YAP1 expression and clinical parameters were analyzed between YAP1 positive group and YAP1 negative group. Kaplan-Meier curve was used to analyze the influence of YAP1 expression on survival of patients.

Results The positive rate of YAP1 in esophageal squamous cell carcinoma was 30.52%. The tumor invasion was deeper in YAP1 positive group (P＜0.001). Kaplan-Meier survival analysis showed that YAP1 positive patients had longer disease-free survival (DFS) and overall survival (OS) among patients surviving longer than 30 months (P＜0.05). The multivariate Cox regression analysis showed that the invasion depth of tumor was an independent factor affecting DFS (HR＝1.371, 95%CI 0.993-1.894, P＝0.035) and OS (HR＝1.489, 95%CI 1.066-2.080, P＝0.020).

Conclusions YAP1 has a certain percentage of positive rate in esophageal squamous cell carcinoma; for patients with survival longer than 30 months, YAP1 positive indicates a better prognosis.