Obesity-induced IL-6 expression promotes the polarization of M2 macrophages and induces secretion of the chemokine CC-chemokine ligand 20 (CCL20) in the CAC microenvironment; CCL20 recruits CC-chemokine receptor 6 (CCR6)-expressing B cells and γδ T cells via chemotaxis, leading to CAC progression [51]. Here, CCL20 is linked to obesity due to melanocortin 4 receptor deficiency.