Elevated BUBR1 Expression Is Associated with Poor Survival in Early Breast Cancer Patients: 15-Year Follow-up Analysis

BUBR1 (budding uninhibited by benzimidazole-related 1) represents the component of a controlling complex in mitosis. Defects in mitotic control complex result in chromosomal instability and, as a result, disturb the mitotic process. This study was aimed at examining the prognostic value linked to the expression of BUBR1 in a group of patients with breast cancer. We analyzed the expression of BUBR1 in 98 stage II breast cancer patients with a median follow-up of 15 years. Immunohistochemical reactions were performed using monoclonal antibodies against BUBR1. We also studied the prognostic value of BUBR1 mRNA expression using the Kaplan-Meier (KM) plotter, which assessed the effect of 22,277 genes on survival in 2422 breast cancer patients. A background database was established using gene expression data and survival information on 2422 patients downloaded from the Gene Expression Omnibus (GEO; Affymetrix HGU133A and HGU133+2 microarrays). The median relapse-free survival was 6.43 years. Univariate and multivariate analyses showed that higher expression of BUBR1 was typical for cases of shorter overall survival, disease-free time, and disease-specific survival. KM plotter analysis showed that elevated BUBR1 mRNA expression had a negative impact on patients' relapse-free, distant metastases-free, and overall survival. Elevated BUBR1 expression was associated with poor survival in early stage breast cancer patients.