During tumor development and growth, IL-37 also acts as an anti-angiogenic factor; expressed by cancer cells, it inhibits the in vitro formation of tubules of human umbilical vein endothelial cells (HUVEC), lowers the expression of matrix metallopeptidase 2 (MMP2) and vascular endothelial growth factor (VEGF) in SK-Hep-1 cells and dampens angiogenesis in the tumors of mice with HCC [23]. The gene discussed is MMP2; the disease is hepatocellular carcinoma.