ESR2 and triple-negative breast carcinoma: The PPIN analysis revealed ESR1, ESR2, PGR, EGFR, IGF1R, FGFR1, KIT, PTEN, mTOR, NOTCH 1, NOTCH 4, NFkB, CCND1, VEGFR3, LRP6, and APC (Table 1) as the candidate genes possessing the triple-negative breast cancer-specific functions and mechanisms.