ERBB2 and breast cancer: In order to assess if Gadd45a expression levels correlated with any of breast cancer subtypes, the 56 breast surgery cases were grouped as follows: Normal (11, benign mammoplasty), Luminal A (9, ER+, PR+, HER2-; LumA), Luminal B (11, ER+, PR+, HER2+), HER2+ (10, ER-, PR-, HER2+), and Triple Negative (15, ER-, PR-, HER2-; TN ).