CTSZ and breast cancer: Meanwhile, we further carried out an interquartile analyses and found that there were association between BC and CTSZ methylation on the site of CTSZ_CpG_1, CTSZ_CpG_5 and CTSZ_CpG_7,8 where the highest OR of CTSZ_CpG_5 was 1.815(95%CI:1.217-2.707, P=0.003, Table 7).