Borealin/Dasra B is overexpressed in colorectal cancers and contributes to proliferation of cancer cells

Borealin/Dasra B, also called cell division cycle associated 8, is a member of the chromosomal passenger complex and plays a crucial role during mitosis and cell division. The expression of this gene has been investigated in several kinds of cancers, but its role in colorectal cancers (CRC) remains to be elucidated. In this study, our in silico analysis using the Oncomine database showed that Borealin was overexpressed in CRC tissues, which was further validated by immunohistochemistry in a cohort of 81 pairs of primary CRC and adjacent non-cancerous tissues. In CRC, Borealin expression was positively correlated with age (P = 0.0079), lymph node metastasis (P = 0.0086), and TNM stage (P = 0.0050). Significant difference in the overall survival time was seen between patients with high and low expression (P < 0.0001). Furthermore, high Borealin expression remained independently prognostic in multivariate analysis (HR 4.556, 95 % CI 1.964–10.567, P = 0.0004). Functional studies showed that suppression of Borealin expression with siRNA could significantly inhibit the growth and induce apoptosis in HCT-116 cells (P < 0.01). These results suggest that Borealin might act as an independent prognostic factor and a potential therapeutic target for patients with CRC.