High expression of biglycan is associated with poor prognosis in patients with esophageal squamous cell carcinoma

Abstract

Biglycan (BGN), an extracellular matrix component, has been reported to play a crucial role in the tumor progression of various cancers. However, the relation between the expression of BGN and clinical prognosis has not been studied yet. We therefore carry out the present study to elucidate the role of BGN in predicting outcomes of patients with esophageal squamous cell carcinoma (ESCC). In this study, the expression of BGN in 170 cases of ESCC tissues and matched 46 adjacent non-tumorous tissues was measured by quantitative real-time PCR and immunohistochemistry. Upregulation of BGN occurred in approximately 60% of primary ESCCs compared with their non-tumor counterparts. In addition, high expression of BGN was significantly associated with clinical stage (P = 0.009), tumor invasion (P = 0.006) and lymph node metastasis (P = 0.046). The 5-year disease-specific survival (DSS) in high expression of BGN group is poorer than that in low level expression group (36.8% VS 57.4%, P = 0.006). Stratified analysis according to the pathological stage revealed its discernibility on DSS was only pronounced in patients with advanced clinical stage (P = 0.010). Cox multivariate analysis revealed that pathologic N category (P < 0.001; hazard ratio, 2.482, 95% CI, 1.576-3.909) and BGN expression (P = 0.019; hazard ratio, 1.713, 95% CI, 1.092-2.688) were two independent prognostic factors. The findings of the present study provide evidence that BGN represents a potential novel prognostic biomarker for resected ESCC patients in advanced clinical stage.

Keywords: BGN; ESCC; prognosis.

Figure 1

A and B: BGN was up-regulated in ESCC. BGN mRNA was markedly increased in tumor tissues than that in paired adjacent non-tumorous tissues. **, P < 0.0001, paired t-test.

Figure 2

Representative of BGN expression in adjacent non-tumorous tissue and ESCC tumor tissues detected by immunostaining with anti-BGN antibody (brown). The slide was counterstained with hematoxylin (original magnification × 200).

Figure 3

A: The correlation of expression of BGN and prognosis of patients with ESCC. Kaplan-Meier curves with univariate analysis showed that patients with high expression of BGN had a poorer disease specific survival than those with low expression of BGN. P = 0.006, log-rank test. B: Stratified survival analysis according to the pathological stage revealed discernibility of BGN expression on DSS was only pronounced in patients with advanced clinical stage (pStage III). P = 0.010, log-rank test.