AHCY and breast carcinoma: TFAP2C (transcription factor AP-2 gamma; activating enhancer binding protein 2 gamma) is involved in mammary development, differentiation, and oncogenesis playing a critical role in gene regulation in hormone responsive breast cancer [45], and AHCY (adenosylhomocysteinase) has been suggested as potentially involved in mastitis defense based on its disease-associated expression [46].