Interestingly, neither ATP levels (Fig. 1D) nor cell growth (Fig. S4) was affected by leptin in MDA‐MB 231 estrogen receptor (ER) negative breast cancer cells, supporting the hypothesis that ATP production and FAO‐mediated via ER‐dependent mechanisms is required for leptin‐induced growth of breast cancer cell. This evidence concerns the gene ESR1 and breast carcinoma.