Finally, we evaluated the effects of metformin on orthotopic pre‐clinical models of post‐surgery tumor samples from one high‐grade serous ovarian tumor WT for BRCA genes (OVA260 tumor), and one high‐grade serous ovarian tumor with a deletion of the exon 20 c.(5243_5277+2788del; 5277+2916_5277+2946delinsGG) of the BRCA1 gene, implanted in nude mice. This evidence concerns the gene BRCA1 and ovarian serous tumor.