CYP19A1 and breast cancer: Taken together, GSE and GSPB2 in vitro treatments decrease oxidative stress and increase steroidogenesis without affecting cell proliferation and viability in human granulosa cells (93).Another study described the ability of grapeseed extract to modulate an aromatase inhibitor in vitro as well as in vivo in aromatase-transfected MCF-7 (MCF-7aro) BC xenograft mice (99).