Expression of γ-tubulin in non-small cell lung cancer and effect on patient survival.

Introduction. It has been reported that overexpression and altered compartmentalization of gamma-tubulin may contribute to tumorigenesis and tumor aggressiveness in a variety of human malignancies. We have shown that gamma-tubulin expression and cellular distribution pattern is also altered in non-small cell lung cancer (NSCLC) (Histol. Histopathol. 2012; 27: 11831194). In the present study we examined the relationship between gamma-tubulin expression and patient overall survival (OS). Material and methods. Immunohistochemistry was performed, with well-characterized anti-gamma-tubulin antibodies, on 109 formalin-fixed, paraffin-embedded NSCLC specimens (p-TNM stage I-III). gamma-Tubulin labeling indexes (LIs) were determined, and the association of gamma-tubulin expression with clinicopathological parameters was evaluated. To analyze OS rates according to gamma-tubulin LIs, patients were categorized into three groups: those with low (0-30%), intermediate (31-69%) or high (70-100%) gamma-tubulin LI. Association of clinicopathological parameters and gamma-tubulin with survival were examined using univariate and multivariate Cox regression analysis. Results. No statistically significant association was seen between gamma-tubulin overexpression and histological type, tumor differentiation, p-TNM stage and adenocarcinoma subtyping. Longer survival was observed in the high gamma-tubulin LI group of patients with p-TNM stages II+III when compared to intermediate or low gamma-tubulin LI groups, but the difference was not statistically significant (p=0.066). On the other hand, when combined low and intermediate gamma-tubulin LI groups (p-TNM stages II+III) where compared to high gamma-tubulin LI group, statistically significant longer survival was observed in high gamma-tubulin group (p=0.021). Conclusion. Our findings suggest that level of gamma-tubulin expression may have an impact on patient survival at more advanced NSCLC stages.