Clinicopathological significance of BMP7 expression in esophageal squamous cell carcinoma

Background. Bone morphogenetic proteins (BMPs) are secreted signaling molecules belonging to the transforming growth factor-β (TGF-β) superfamily of growth factors. Recent studies have shown that the influence of the expression of BMP7 was altered in several tumors. The purpose of the current study was to examine the expression of BMP7 in esophageal squamous cell carcinoma and to clarify the clinical impact of BMP7 expression in esophageal squamous cell carcinoma (ESCC). Methods. A total of 180 patients with ESCC who underwent surgical resection from 1991 to 2004 were eligible for this study. The expression of BMP7 in esophageal tumor tissues was examined immunohistochemically. Results. BMP7 expression was found in the cytoplasm of cancer cells. BMP7 positivity was observed in 61.7% of tumors. The BMP7-positive group had deeper progression, more advanced stages, and greater venous invasion than those without BMP7 expression (p<0.001, p<0.005, and p<0.0005, respectively). In addition, expression of BMP7 correlated with poorer prognosis (p<0.0005). Multivariate analysis showed that BMP7 expression status was an independent prognostic factor (p<0.05). Conclusions. Patients with expression of BMP7 in ESCC had high malignant potential. BMP7 could be a useful prognostic marker for patients with ESCC.