BDP1 Alterations Correlate with Clinical Outcomes in Breast Cancer

SIMPLE SUMMARY: Breast cancer accounts for 30% of all new cancer diagnoses in the United States. The most common type of breast cancer is invasive breast cancer. A hallmark trait of breast cancer is uncontrolled cell growth due to genetic alterations. TFIIIB-mediated RNA polymerase III transcription is specifically deregulated in human cancers. The TFIIIB BDP1 subunit is not well characterized in human cancer. The objective of this study was to analyze publicly available clinical cancer datasets to determine if BDP1 alterations correlate with clinical outcomes in available breast cancer datasets. BDP1 copy number and expression negatively correlate with breast cancer outcomes, including stage, grade, and mortality. ABSTRACT: TFIIIB is deregulated in a variety of cancers. However, few studies investigate the TFIIIB subunit BDP1 in cancer. BDP1 has not been studied in breast cancer patients. Herein, we analyzed clinical breast cancer datasets to determine if BDP1 alterations correlate with clinical outcomes. BDP1 copy number (n = 1602; p = 8.03 × 10(−9)) and mRNA expression (n = 130; p = 0.002) are specifically decreased in patients with invasive ductal carcinoma (IDC). In IDC, BDP1 copy number negatively correlates with high grade (n = 1992; p = 2.62 × 10(−19)) and advanced stage (n = 1992; p = 0.005). BDP1 mRNA expression also negatively correlated with high grade (n = 55; p = 6.81 × 10(−4)) and advanced stage (n = 593; p = 4.66 × 10(−4)) IDC. Decreased BDP1 expression correlated with poor clinical outcomes (n = 295 samples): a metastatic event at three years (p = 7.79 × 10(−7)) and cancer reoccurrence at three years (p = 4.81 × 10(−7)) in IDC. Decreased BDP1 mRNA correlates with patient death at three (p = 9.90 × 10(−6)) and five (p = 1.02 × 10(−6)) years. Both BDP1 copy number (n = 3785; p = 1.0 × 10(−14)) and mRNA expression (n = 2434; p = 5.23 × 10(−6)) are altered in triple-negative invasive breast cancer (TNBC). Together, these data suggest a role for BDP1 as potential biomarker in breast cancer and additional studies are warranted.