Again, in these PDX models metformin treatment only significantly reduced tumor growth in the BRCA1 mutated model (Fig 5C and D), with a tumor volume after treatment of 0.37 cm3 in control versus 0.19 cm3 in metformin‐treated animals, whereas WT BRCAs tumors had a volume post‐treatment of 0.66 cm3 versus 0.56 mm3 in control and metformin‐treated mice, respectively. This evidence concerns the gene BRCA1 and neoplasm.