Table 1

HIN-1 and BRCA1 promoter methylation in various breast cancer types

HIN-1 and BRCA1 promoter methylation was evaluated by MSP. Both partially and completely methylated samples are listed together as methylated. Subtypes of unselected cancers do not sum to the total because complete immunohistochemical data were not available for all tumors. BRCA1-like tumors were defined as ER- and HER2-negative high-grade tumors.

Breast cancer typeHIN-1BRCA1
Sample sizeUnmethylatedMethylatedSample sizeUnmethylatedMethylated
No. (%)No. (%)No. (%)No. (%)
Sporadic cancers11437 (32)77 (68)9665 (68)31 (32)
 ER+HER2+256 (24)19 (76)2515 (60)10 (40)
 ER+HER2−263 (12)23 (88)2418 (75)6 (25)
 ER−HER2+2912 (41)17 (59)2918 (62)11 (38)
 BRCA1-like149 (64)5 (36)1514 (93)1 (7)
BRCA1-associated1816 (89)2 (11)1816 (89)2 (11)
Familial (non-BRCA1)52 (40)3 (60)66 (100)0 (0)