Objectives: Non-small cell lung cancer (NSCLC) is aggressive and associated with a poor prognosis. Recent studies have revealed that several genes are involved in the origin and progression of NSCLC. Kruppel-like factor 6 (KLF6) inactivation has been shown in some malignant tumors. KLF6-SV1, as one of the alternatively spliced KLF6 isoforms, has been found to be correlated with metastatic potential and poor survival in some cancers. The purpose of this study was to investigate the clinical and prognostic significance of KLF6-SV1 expression in NSCLC patients after curative resection.
Patients and methods: A total of 79 patients were enrolled in this study. Enumeration data were analyzed using the chi-squared test or Fisher's exact probability test. Measurement data were represented as average±SD and t-test (homoscedasticity) or t'-test (homoscedasticity uneven). Univariate analysis was performed by modeling Kaplan-Meier survival curves. The log-rank test was used to calculate the survival rate. Multivariate analysis was carried out by the use of the Cox proportional hazard model.
Results: KLF6-SV1 expression was correlated with pN (P<0.05) and pTNM stage (P<0.05). The expression of KLF6-SV1 in the adenocarcinoma group was significantly higher than that in the squamous cell carcinoma group (P<0.05). The 5-year survival rate for 79 NSCLC patients was 40.5%, and it was significantly associated with differentiation (P<0.05), pN (P<0.01), pTNM stage (P<0.01) and high expression of KLF6-SV1 (P<0.01). Cox multivariate regression demonstrated that differentiation, pN and KLF6-SV1 expression were independent factors for the 5-year survival rate.
Conclusion: KLF6-SV1 expression in adenocarcinoma was significantly higher than that in the squamous cell carcinoma, and high expression of KLF6-SV1 was significantly associated with pN and pTNM stage and poor survival in NSCLC patients.
Keywords: KLF6-SV1; Western blot; immunohistochemistry; non-small cell lung cancer; real-time PCR.