STAT3 and obesity due to melanocortin 4 receptor deficiency: Here, we find that long‐term CRMP treatment markedly reduced the occurrence of HCC in male B6D2 mice, presumably due to a reduction in hepatic oxidative stress (Sakurai et al., 2008) and the obesity‐enhanced production of IL‐6 and TNFα, which causes hepatic inflammation and activation of oncogenic STAT3 (Park et al., 2010), and which we have shown to be reduced in aging C57BL/6 male mice treated with CRMP for 4 weeks (Figure 4c–e).