MMP9 and ovarian carcinoma: Norepinephrine can increase the expression of VEGF in ovarian cancer cells (Lutgendorf et al., 2003; Thaker et al., 2006; Chakroborty et al., 2009; Szubert et al., 2016) and promote the migration of endothelial cells by inducing the expression of MMP-2 and MMP-9 (Bergers et al., 2000; Huang et al., 2002; Thaker et al., 2006; Landen et al., 2007; Gonzalez-Villasana et al., 2015), thereby inducing the formation of new blood vessels in tumors.