Compared with Normal and FCC groups, Pin1 expression was significantly increased in DCIS and IDC groups (Fig. 1a, c, DCIS vs Normal: P < 0.001; IDC vs Normal: P = 0.003; DCIS vs FCC: P = 0.004; IDC vs FCC: P = 0.043), but there were no significant differences between the FCC group and the Normal group, and also between the DCIS group and the IDC group (Fig. 1c, FCC vs Normal: P = 0.39, DCIS vs IDC: P = 0.154). This evidence concerns the gene PIN1 and ductal breast carcinoma in situ.