We could not see any differences in the expression of IL-12 (M1) vs. IL-10 (M2) macrophages in the mammary tumor microenvironments of obese, overweight or lean mice, suggesting that obesity is not particularly related to M1 or M2 macrophages in the mammary tumor microenvironment. Here, IL10 is linked to obesity due to melanocortin 4 receptor deficiency.