The IHC analysis showed that MYC and DNMT3A were up‐regulated in TNBC tissues than other breast cancer subtypes (H‐score of MYC, ER+, 148.0 ± 12.2; HER2+, 145.2 ± 15.3; TNBC, 182.5 ± 8.3; H‐score of DNMT3A, ER+, 127.3 ± 9.3; HER2+, 150.5 ± 14.6; TNBC, 160.6 ± 7.9) (Figure 1D and S1A). Here, DNMT3A is linked to breast cancer.