LEP and neoplasm: Subsequently, in a similar study, the investigators observed that the anti-diabetic agent metformin treatment in RD and HED mice resulted in a significant reduction in tumour burden as well as decreased levels of growth factors/cytokines such as IGF-1, IL-6 and leptin in both plasma and ascitic fluid, akin to the CRD mice (Al-Wahab et al., 2015).