Increased expression of chitinase 3-like 1 is a prognosis marker for non-small cell lung cancer correlated with tumor angiogenesis.

Increasing evidence demonstrated that chitinase 3-like 1 (CHI3L1) was highly expressed and tightly associated with human tumor development and progression. However, its precise role in non-small cell lung cancer (NSCLC) remains to be delineated. The aim of this study was to examine CHI3L1 expression in patients with NSCLC and explore the relationship of CHI3L1 protein with clinicopathologic factors, tumor angiogenesis, and prognosis. CHI3L1 protein and intratumoral microvessels were examined by immunohistochemical staining in 95 NSCLC patients. Intratumoral microvessel density (MVD) was measured by counting CD34-positive immunostained endothelial cells. Quantitative real-time PCR (qRT-PCR) analyses were used to investigate the CHI3L1 expression status in tissues. Our result showed that CHI3L1 was significantly up-regulated in NSCLC tissues. In addition, univariate and multivariate analysis demonstrated that CHI3L1 protein overexpression and high MVD were significantly associated with tumor relapse. Although CHI3L1 overexpression and high MVD indicated poor overall survival (P < 0.05), multivariate analysis suggested that only CHI3L1 overexpression was an independent prognostic marker for unfavorable overall survival in patients with NSCLC (P < 0.05). The current results demonstrated that CHI3L1 may be a promising biomarker to identify individuals with poor prognostic potential and a possible target for anti-angiogenic therapy in patients with early stage NSCLC.