Solid tumor exhibits different pH profiles compared to normal tissues, which points at a metabolic shift toward acid‐producing pathways, reflecting both oncogenic signaling and the development of hypoxia.35 The sodium bicarbonate cotransporter NBCn1 is the predominant mechanism of acid extrusion in primary breast carcinomas compared to normal tissues affecting intracellular pH levels.36 Finally, we detected evidence of estrogen 16‐alpha‐hydroxylase activity, which is one of the earliest reported biomarkers for breast cancer.37 This evidence concerns the gene SLC4A7 and breast cancer.