EGFR and ovarian cancer: In contrast to ovarian granulosa cells HGL5 where PPE treatment did not exert any significant effect, PPE treatment decreased the release of growth factors – transforming growth factor β 2 (TGF-β2) and epidermal growth factor (EGF) at the highest dose of 100μg/mL PPE used (p<0.001), as well as the expression of their receptors TGFBR2 (p<0.001) and EGFR (p<0.05) in ovarian cancer cells OVCAR-3, in a dose-specific manner (Figure 5).