RAB27B and breast cancer: BCG is the standard immunotherapy for patients with moderate‐ and high‐risk NMIBC.[144] AR overexpression has been shown to decrease IL‐6 levels by attenuating the NF‐kB pathway in BC cells, subsequently reducing the efficacy of BCG therapy.[145] Specifically, AR expression diminishes the effectiveness of BCG; however, the combination of BCG with ADT or the AR degradation enhancer ASC‐J9 enhances BCG efficacy by recruiting IL‐6‐related monocytes and CAMs in mouse models.[146] Mizushima et al.[15] reported that the AR decreased the efficacy of BCG by enhancing RAB27B/SYTL3‐induced exocytosis.