LCN2 and obesity due to melanocortin 4 receptor deficiency: Wolk et al. and Hadidi et al. provided the evidence that LCN2 is significantly up-regulated in keratinocytes of psoriatic skin lesions, and the LCN2 level is positively correlated with IL-1β [88, 122], while IL-1β promotes obesity and psoriasis synergistically, thus emphasizing the regulatory nature of LCN2 in linking psoriasis and obesity.