PARP9 and breast cancer: Moreover, subtype-specific analysis of BC revealed that high expression of BAL1 was significantly correlated with prolonged RFS in ERpositive (HR = 0.82, p = 0.035), ERnegative (HR = 0.6, p = 5.9 × 10−5), Basal (HR = 0.44, p = 2.2 × 10−7), luminal B (HR = 0.72, P = 0.015), HER2- (HR = 0.73, p = 5 × 10−4), and HER2+ (HR = 0.68, p = 0.012) subtypes, but not in the luminal A subtype (HR = 0.79, p = 0.19) (Fig. 5B-H).