['To assess the interaction of the hydroxy-3-methylglutaryl-coezyme A reductase inhibitor lovastatin individually and in combination with 3 natural plant compounds on hepatocarcinoma cell growth.', 'The cytotoxic effects of lovastatin in combination with epigallocatechin gallate (EGCG), capsaicin, and curcumin were investigated in cultured hepatocarcinoma cells (Hep-G2), and the interactions were depicted using an isobolographical analysis.', 'All compounds tested reduced Hep-G2 cell growth to various degrees. In terms of individual cytotoxicity LC50 values, curcumin (55.5 ± 7.6\xa0µmol/L) was found to be the most cytotoxic and had the lowest LC50, followed by lovastatin (62.3 ± 5.34\xa0µmol/L), EGCG (82.1 ± 15.1\xa0µmol/L), and capsaicin (199.5 ± 11.72\xa0µmol/L). The individual LC50 values were used in a fix-fraction isobolographical analysis to predict the effect of combining lovastatin and the individual compounds. Experimentally derived LC50 values of 5 fractions containing fixed proportions of lovastatin to each of the 3 natural compounds allowed comparison of the experimentally derived LC50 to the predicted values depicted on the isobologram.'] Does lovastatin interact with natural products to influence cultured hepatocarcinoma cell ( hep-g2 ) growth?