Overexpression of S100A13 protein is associated with tumor angiogenesis and poor survival in patients with early‐stage non‐small cell lung cancer

BACKGROUND: S100A13 plays a key role in tumor growth and metastasis. The purpose of this study was to investigate the prognostic significance of S100A13 expression, microvessel density (MVD), and survival in early stage non‐small cell lung cancer (NSCLC). METHODS: In silico analysis was performed to determine the associations between S100A13 and NSCLC. The data of 82 patients with early‐stage NSCLC who underwent radical resection were evaluated. Paraffin‐embedded tumor specimens were stained with S100A13 and CD31 (a specific endothelial marker) using immunohistochemical methods. Prognostic significance was assessed by univariate and multivariate analyses. RESULTS: S100A13 messenger RNA was overexpressed in NSCLC, especially in advanced stage. Of the 82 NSCLC specimens examined, 37 (45.1%) cases exhibited S100A13 overexpression and 31 (37.8%) showed high MVD. Univariate analysis indicated that gender, age, smoking status, histology type, tumor differentiation, and T stage were not significantly associated with prognosis. However, the overall and disease‐free survival rates of patients with S100A13 overexpression and high MVD were significantly lower than in the remaining cases. Multivariate analysis demonstrated that only S100A13 overexpression was an independent factor for poor prognosis in early‐stage NSCLC. Statistical analysis demonstrated that the MVD was significantly higher in tumors with high (67.6%, 25/37) compared to low S100A13 expression (13.3%, 6/45) (P < 0.01). CONCLUSIONS: High S100A13 expression is closely associated with high intratumoral angiogenesis and poor prognosis in patients with stage I NSCLC. Immunohistochemical evaluation of S100A13 expression, along with an examination of the perioperative extent of angiolymphatic invasion, has value for predicting prognosis.