Prognostic significance of altered expression of SDC2 and CYR61 in esophageal squamous cell carcinoma

The transforming growth factor β (TGF-β) signaling pathway plays an important role in growth and development, and is critically involved in the genesis and development of tumors. Syndecan-2 (SDC2) and Cysteine-rich 61 (CYR61) are important genes in this pathway and SDC2 is known to be a significant upstream regulator of TGF-β signaling. However, the roles of SDC2 and CYR61 in the development of esophageal squamous cell carcinoma (ESCC) remain unclear. In the present study, we investigated the relationship between SDC2 and CYR61 mRNA expression levels and disease prognosis in patients with ESCC. The mRNA expression of SDC2 and CYR61 was detected by quantitative real-time RT-PCR in 77 tissue specimens. Quantitative real-time RT-PCR showed that SDC2 and CYR61 mRNA expression levels were aberrant in ESCC tissue (P<0.01) and that SDC2 mRNA expression was significantly associated with tumor size (P=0.024) in ESCC. CYR61 mRNA expression was significantly associated with regional lymph node metastasis (P=0.034) and tumor size (P=0.03). A positive correlation between SDC2 and CYR61 (r=0.770; P<0.001) mRNA expression was observed. Moreover, we observed significant associations between altered expression of SDC2/CYR61 and regional lymph node metastasis (P=0.009) and TNM stages (P=0.033). Aberrant mRNA expression of CYR61 and SDC2/CYR61 (P=0.005 and P=0.026, respectively) were significantly associated with patient survival time. The multivariate Cox regression analysis showed that SDC2 and CYR61 were independent prognostic factors for survival. Our findings suggest that SDC2 may act as an a upstream regulator of the TGF-β signaling pathway and regulate the expression of downstream target genes. Moreover, SDC2 and CYR61 expression affect the severity of cancer, and the survival of patients with ESCC. Importantly, we report that SDC2 and CYR61 are significant, independent prognostic factors for survival in ESCC. These findings may have implications for targeted therapies in patients with ESCC.