Prognostic Significance of MYH9 Expression in Resected Non-Small Cell Lung Cancer

INTRODUCTION: Myosin-9 (MYH9) belongs to the myosin superfamily of actin-binding motor protein. Recently, MYH9 has been thought to be associated with cancer cell migration, invasion, and metastasis. The aims of this study were to immunohistochemically examine MYH9 expression in surgically resected non-small cell lung cancer (NSCLC), and evaluate its correlations with clinicopathological parameters and the prognosis of patients. METHODS: MYH9 expression was immunohistochemically studied in 266 consecutive resected NSCLCs, and its associations with clinicopathological parameters were evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of MYH9 expression on survival. RESULTS: MYH9 expression was detected in 102 of 266 (38.3%) NSCLCs. MYH9 expression was significantly correlated with the adenocarcinoma histology (P = 0.014), poorer differentiation ((P = 0.033), intratumoral vascular invasion and lymphatic invasion ((P = 0.013 and P = 0.045 respectively), and a poorer prognosis ((P = 0.032). In addition, multivariable analysis revealed that MYH9 expression independently predicted a poorer survival (HR, 2.15; 95%CI, 1.17-3.92; (P = 0.01). CONCLUSION: The present study revealed that MYH9 is expressed in a subset of NSCLC with a more malignant nature, and its expression is an indicator of a poorer survival probability.