ERBB2 and breast cancer: When considering different molecular subtypes of BC, GRPR was highly expressed in 86.2% of luminal A-like tumors, 70.5% of luminal B-like HER2-negative tumors, 82.8% of luminal B-likeB-like HER2-positive tumors, 21.3% of HER2-enriched tumors, and 7.8% of triple-negative tumors.