Differential expression of BUB1B in cancers of the breast.
Breast cancer affects women at relatively high frequency (1). We mined published microarray datasets (2, 3) to determine in an unbiased fashion and at the systems level genes most differentially expressed in the primary tumors of patients with breast cancer. We report here significant differential expression of the gene encoding the BUB1 mitotic checkpoint serine/threonine kinase B, BUB1B, when comparing primary tumors of the breast to the tissue of origin, the normal breast. BUB1B was also differentially expressed in the tumor cells of patients with triple negative breast cancer. BUB1B mRNA was present at significantly higher quantities in tumors of the breast as compared to normal breast tissue. Analysis of human survival data revealed that expression of BUB1B in primary tumors of the breast was correlated with overall survival in patients with basal and luminal A subtype cancer, but in a contrary manner. BUB1B may be of relevance to initiation, maintenance or progression of cancers of the female breast.