Prognostic role of myeloid cell leukemia‐1 protein (Mcl‐1) expression in human gastric cancer

Background Myeloid cell leukemia-1 protein (Mcl-1), an anti-apoptotic member of Bcl-2 family, has been reported to be correlated with tumor progression. The purpose of this study was to establish the prognostic value of Mcl-1 expression in human gastric cancer. Methods Western blot assay was performed to detect the expression of Mcl-1 protein in human gastric cancer cell lines and tissues, while Mcl-1 expression in resected gastric cancer tissue samples was analysed by immunohistochemistry. Results The level of Mcl-1 protein expression in gastric cancer cell lines was significantly higher than that in gastric mucosa epithelial cell line. Moreover, the expression level of Mcl-1 protein was significantly higher in gastric cancer tissues than corresponding noncancerous tissues. Expression was correlated with T classification (P = 0.003), metastasis (P = 0.001), clinical stage (P = 0.010), and venous invasion (P = 0.004). Patients with high Mcl-1 expression showed poorer 5-year overall survival than patients with low Mcl-1 expression (P = 0.012; log-rank test). Further univariate and multivariate analysis suggested that high Mcl-1 expression was an independent prognostic marker for the disease. Conclusion Mcl-1 is highly upregulated in gastric cancer and high Mcl-1 expression is correlated with a poor prognosis in gastric cancer patients. Thus, Mcl-1 can be utilized as an independent prognostic factor. J. Surg. Oncol. 2009;100:396–400. © 2009 Wiley-Liss, Inc.