NGF and ovarian cancer: Given that CAOV3, OVCAR3 and SKOV3 cells released endogenous NGF, we explored the changes of basal expression levels of β-catenin after treatment with NGF/NGFRs-related inhibitors without exogenous NGF to better verify whether the endogenous NGF was biologically active in regulating the expression of β-catenin in ovarian cancer cells.