BubR1 and AURKB overexpression are associated with a favorable prognosis in gastric cancer

The majority of human solid tumors exhibit aneuploidy caused by impairment of the mitotic checkpoint. Since the Mad2, BubR1 and Aurora kinase B (AURKB) proteins are involved in the mitotic checkpoint, we investigated Mad2, BubR1 and AURKB mRNA expression and its effect on clinicopathological parameters and prognosis in 100 consecutive patients who underwent surgical resection for gastric cancer. Mad2, BubR1 and AURKB mRNA expression levels in gastric cancer tissues and corresponding normal gastric mucosa were compared by real-time quantitative RT-PCR. The data were then correlated to clinicopathological parameters and prognosis. The expression of Mad2, BubR1 and AURKB mRNA was found to be significantly higher in cancer tissue compared to normal tissue. BubR1 and AURKB expression was significantly higher during the earlier stages of the disease. Patients with high BubR1 expression had improved relapse-free survival and overall survival compared to patients with low BubR1 expression. Multivariate analysis of stage II and III patients indicated that high expression of BubR1 and/or AURKB was associated with improved overall survival. We conclude that overexpression of BubR1 and AURKB is associated with a low risk of gastric cancer progression, and that overexpression of BubR1 and/or AURKB can therefore be used to identify gastric cancer patients with a favorable prognosis.