Correlation of Aurora-A expression with the effect of chemoradiation therapy on esophageal squamous cell carcinoma

Background: Chemoradiation therapy (CRT) is one of the most useful treatments for esophageal squamous cell carcinoma (ESCC). However, because some patients respond well to CRT and others do not, it is important to be able to predict response to CRT before beginning treatment by using markers. Aurora-A encodes a cell cycle regulated serine/threonine kinase that has essential functions in centrosome maturation and chromosome segregation. In this study, we investigated the relationship between the expression of Aurora-A and the response to CRT in patients with ESCC. Methods: We immunohistochemically investigated the expression of Aurora-A in biopsy specimens of untreated primary tumors of 78 patients with ESCC and determined the relationship between Aurora-A levels and patient responses to CRT, which consisted of 5-fluorouracil plus cisplatin and 40 Gy of radiation. Results: Tumors were judged as Aurora-A positive when more than 10% of the cancer cells displayed a distinct positive nuclear anti-Aurora-A immunoreaction by immunohistochemical evaluation. The tumors of 46 of 78 patients (58.9%) displayed positive expression of Aurora-A. In terms of clinical response the percentage of patients showing complete response (CR), incomplete response/stable disease of primary lesion (IR/SD), and progressive disease (PD) was 19.2, 69.2, and 11.5%, respectively. In terms of histological response the tumor grade of the 41 patients who underwent surgery was as follows: grade 1, 48.8%; grade 2, 29.2%; grade 3, 22.0%. CRT was effective for patients who had Aurora-A (+) tumors (clinically: P=0.0003, histologically: P=0.036). Conclusions: Our results suggest that Aurora-A expression in biopsy specimens of primary tumors is associated with CRT efficacy in patients with ESCC. Assessment of Aurora-A expression in biopsy specimens maybe useful for regarding the potential utility of CRT therapy for patients with ESCC before treatment.