RESUMEN
<p><b>OBJECTIVE</b>The aim of this study was to explore the expression of activin A in esophageal squamous cell carcinoma and its clinical significance.</p><p><b>METHODS</b>Immunohistochemical (IHC) staining was used for detecting the expression of tissue activin A in sixty-four patients with esophageal squamous cell carcinoma, and enzyme-linked immunosorbent assay (ELISA) was used for detecting the serum activin A in the patients before and after surgery. The relationship between expression of activin A in the esophageal cancer tissue with clinicopathological features and its influence on prognosis were analyzed.</p><p><b>RESULTS</b>The positive expression rate of activin A in esophageal squamous cell carcinoma was 82.8% (53/64), and that of normal esophageal epithelium was 6.7% (2/30), showing a very significant difference between them (P < 0.001). Expression of activin A was correlated with both lymph node metastasis and invasion depth of the tumor (all P < 0.05), and the expression of activin A was positively correlated with lymph node metastasis (r = 0.321, P < 0.05) and invasion depth of the tumor (r = 0.417, P < 0.05). The serum activin A of the patients before and after surgery was (911 ± 276) pg/ml and (667 ± 236) pg/ml, respectively, showing a significant difference (P = 0.005). Univariate and multivariate analyses indicated that expression of activin A and lymph node metastasis were independent influencing factors for prognosis in patients with esophageal squamous cell carcinoma (all P < 0.05).</p><p><b>CONCLUSIONS</b>Activin A may play an important role in the pathogenesis and development of esophageal squamous cell carcinoma, and it has an important reference value in the estimation of diagnosis and prognosis for esophageal squamous cell carcinoma.</p>