Expression of heat shock protein 70 in grossly resected esophageal squamous cell carcinoma

Background. The aim of the present study was to use immunohistochemical methods to clarify the clinical implication of heat shock protein (HSP) 70 expression in esophageal squamous cell carcinoma and to investigate the function of HSP70 as a chaperone for p53. Methods. Seventy-one patients with esophageal squamous cell carcinoma were admitted in the present study. Expression of HSP70 was analyzed by immunohistochemistry and correlated with TNM classification, vessel invasion, p53 expression, and clinical outcome after operation. Results. Overexpression of HSP70 was related to sex (p< 0.05), tumor configuration (p< 0.05), lymph node metastasis (p< 0.01), and lymphatic vessel invasion (p< 0.05). Expression of p53 and HSP70 were not correlated with each other (p = 0.824). Esophageal squamous cell carcinoma with HSP70 expression exhibited a significantly better prognosis compared with HSP70-negative esophageal squamous cell carcinoma in univariate analysis (p< 0.05), but no significance was found in multivariate analysis. Conclusions. We suggest that HSP70 expression might be of use to assess the progression, lymph node metastasis, and lymphatic vessel invasion of esophageal squamous cell carcinoma. Inasmuch as both lymph node metastasis and HSP70 expression are prognostic variables in esophageal squamous cell carcinoma, examination of HSP70 expression may be of use to assess clinical outcome after operation.