We have found that the way that the drug resistant MCF-7 EpiR and MCF-7 TAXR cells and the TNBC MDA-MB-231 cells metabolize the palmitic acid derived from mature adipocytes in a different manner, in comparison to the parental drug-sensitive MCF-7 as well as to the luminal B and HER2+ cell lines, suggesting that more malignant and drug-resistant breast cancer cells acquire a specific PC biosynthesis pattern that differ from the drug-sensitive and less metastatic breast cancer cells. The gene discussed is ERBB2; the disease is breast cancer.