Although the exact mechanisms connecting cancer and obesity are unknown, some of the proposed ways include the regulation of obesity-associated adipokines such as leptin, adiponectin, and resistin; an increase in plasma insulin and glucose intolerance; and other proinflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) [11,12,13]. Here, RETN is linked to obesity due to melanocortin 4 receptor deficiency.