SERPINE1 and invasive lobular breast carcinoma: Interestingly, significantly higher PAI-1 expression was detected in invasive lobular breast carcinoma (ILC) and invasive ductal breast carcinoma (IDC) than in normal tissues (N), although no significant difference was found between mixed lobular & ductal breast carcinoma (MLD) and normal tissues by analysis of TCGA database (Figure 3A).