IR and IGFR1 play crucial roles in cancer procession and development, overactivation of these receptors is common is cancer cells, with a particular overexpression in dedifferentiated cell, leading to resistance to different anti-tumor therapies.114 Strong evidence suggests the link between type 2 diabetes mellitus, obesity and the development and progression of tumors,115–117 thus, even if the IR pathway gained attention for the antidiabetic therapies, nowadays it represents a target for antitumor therapies. The gene discussed is INSR; the disease is obesity due to melanocortin 4 receptor deficiency.