MIA PaCa-2 (A–C) and HPAF-II (D) pancreatic cancer cells were cultured for 72h in the presence of indicated doses of embelin or ellagic acid or combination of both compounds. (A) Apoptosis was assessed by measuring internucleosomal DNA fragmentation by ELISA. Proliferation was assessed by MTT assay (B, D) or cell counting (B). For A, B and D, the measures are relative to control. P-values are for one-sided one-sample (for A, B and D) and two-sample (for C) t-tests comparing with controls (1 for A, B and D). P* is the p-value for testing the synergistic effect. A synergistic effect is defined as that the mean difference between controls and the combination group is greater than the sum of the mean differences between controls and embelin group and between controls and ellagic acid group. With Bonferroni’s adjustment, p<0.0125 are considered as significant.