In addition, obesity and overweight increased inflammation and oxidative stress, altered the levels of JAK, STAT3, Akt, mTOR, NF-κB and cyclin D1, and enhanced lung epithelial proliferation and the EMT, thereby demonstrating plausible links between positive energy balance states and lung cancer promotion. This evidence concerns the gene AKT1 and obesity due to melanocortin 4 receptor deficiency.