KLK5 and breast cancer: Interestingly, expression of KLK5 was high in basal-like and normal-like breast cancer subtypes with a reduction in levels in luminal B. There was reduced expression in normal tissue and basal subtypes with higher expression in luminal (ER+) and Her-2 subtypes for ITGB5, EZR, COL12A1, and COL24A1.