Objective: To investigate the expression of forkhead box M1 (FOXM1) and its correlation with clinicopathological features and prognosis in patients with non-small cell lung cancer (NSCLC).
Methods: The expression of FOXM1 in 68 cases of NSCLC was detected by immunohistochemistry. The FOXM1 expression in 6 tumor tissues (3 cases with negative and 3 cases with positive expression of FOXM1) was analyzed by Western blotting to confirm the immunohistochemical results. The correlation of the expression of FOXM1 with clinicopathalogical features and overall survival of the NSCLC patients was analyzed.
Results: The expression of FOXM1 protein was detected in the nuclei or cytoplasms of the tumor cells. The positive expression rate of FOXM1 was 36.8% (25/68). Western blotting confirmed the immunohistochemical results. The expression level of FOXM1 in advanced stage cancer was significantly higher than that in early stage NSCLC (P = 0.001). The median OS was 23.0 months in patients with negative expression of FOXM1 and 13.0 months in those with positive expression (P = 0.001). Univariate analysis revealed that histological grade, lymph nodes status, TNM stage and FOXM1 expression were significantly associated with prognosis in the NSCLC patients (P < 0.05). The Cox multivariate analysis demonstrated that lymph nodes status, TNM stage and FOXM1 expression were independent poor prognostic factors (P < 0.05).
Conclusion: The expression status of FOXM1 in NSCLC is an independent prognostic factor and negatively correlated with prognosis.