We have shown that the inhibition of leptin signalling in vitro and in vivo by our innovative leptin peptide receptor antagonists (PEG-LPrA) significantly decreased the levels of vascular endothelial growth factor (VEGF) and its receptor type 2 (VEGFR2) before hypoxia is manifested (Gonzalez-Perez et al, 2010) in breast cancer and stroma cells, while simultaneously reducing establishment and growth of tumours in syngeneic (Gonzalez et al, 2006), xenograft (Rene Gonzalez et al, 2009) and 7,12-dimethylbenz(a)anthracene-diet-induced obesity (unpublished) mouse models of breast cancer. This evidence concerns the gene LEP and breast carcinoma.