IGF1 and obesity due to melanocortin 4 receptor deficiency: The molecular mechanisms that explain the obesity and cancer connection include abnormalities in the IGF1 axis and hyperinsulinemia and insulin resistance, altered steroid metabolism which leads to higher concentrations of estrogen levels from peripheral aromatization in adipose tissue, subclinical chronic low-grade inflammation, oxidative stress, alterations in adipocytokine pathophysiology, and disruptions in the microenvironment, such as vascular changes or epithelial-mesenchymal transition [8].