ADAMTS-6 is a predictor of poor prognosis in patients with esophageal squamous cell carcinoma

A disintegrin and metalloprotease with thrombospondin motif (ADAMTS) enzymes play important roles in cell functions including adhesion, invasion, migration, and proliferation. ADAMTS-6 is a member of the ADAMTS family; reports of its relationship with esophageal squamous cell carcinoma (ESCC) progression are rare. It is unclear whether ADAMTS-6 could be an independent ESCC biomarker. ADAMTS-6 expression was detected by immunohistochemistry (IHC) in 171 paraffin-embedded ESCC specimens; relationships with patients' clinicopathological features and Twist-1 expression were analyzed by the Pearson Chi-square method, respectively. Overall survival (OS) and disease-free survival (DFS) were determined using the Kaplan–Meier method and compared using the long-rank test. ADAMTS-6 was expressed mainly in the cytoplasm and nucleus; the expression was significantly higher in tumor tissues. Increased expression of ADAMTS-6 correlated with clinical stage (P = 0.009), pT stage (P = 0.042), lymph node metastasis (P = 0.014) and recurrence (P = 0.033). There were no significant correlations between ADAMTS-6 expression and other clinicopathological parameters including age, sex, tumor size, distant metastasis, differentiation, …chemotherapy, radiotherapy, CD68 expression and epithelial mesenchymal transition (EMT) status. Kaplan–Meier survival curves revealed that upregulated expression of ADAMTS-6 indicated short OS (P = 0.001) and DFS (P = 0.002). Multivariate analysis confirmed that high ADAMTS-6 expression was an independent factor for ESCC prognosis. ADAMTS-6 expression was significantly correlated with Twist-1 expression in ESCC cancer cells (P = 0.007) and stromal cells (P