IGF1 and obesity due to melanocortin 4 receptor deficiency: IGF-1 is one of the potent activators of cellular proliferation via the protein kinase B signaling pathway, an inhibitor of apoptosis, and exerts a mitogenic effect via the activation of mitogen-activated protein kinases and expression of proto-oncogenes [11]. Hepatic lipid accumulation in obesity has been linked to lipotoxicity, which interferes with cellular signaling mechanisms and regulation of gene transcription, leading to the activation of oncogenic pathways.