One showed that plasminogen activator inhibitor-1 (PAI-1), released by BC cells, is required to activate lysyl hydrolase-2 (PLOD-2) in CAAs, resulting in collagen remodeling and metastasis formation [131]; the other one reported that obesity causes an increase in TAMs that secreting IL-1b activate adipocytes to produce angiopoietin-like 4 (ANGTL4) that in turn promotes angiogenesis in breast cancer [132]. The gene discussed is SERPINE1; the disease is obesity due to melanocortin 4 receptor deficiency.