Antitumor activity of 2 new evodiamine derivatives against small-cell lung cancer cells in vitro

Abstract

Objective To investigate the antitumor activity and the underlying mechanisms of 2 new derivatives of evodiamine (EVO), namely nitro evodiamine derivatives (END) and amino evodiamine derivatives (EAD), in cultured small-cell lung cancer (SCLC) cells. Methods Human SCLC cell line H1688 was treated with EVO, END, or EAD at different concentrations for 24, 48, or 72 h, and the changes in the cell viability were assessed using MTT assay. The effects of treatment with 10 μmol/L EVO, END or EAD for 24 h on cell apoptosis and cell cycle were investigated using flow cytometry. Western blotting was performed to detect the changes in the expressions of Caspase-9, Caspase-12, Caspase-3, and cytochrome C (Cyt C) in the cells following treatment with 10 μmol/L EVO, END or EAD for 48 h. Results MTT assay showed that treatment with END or EAD for 24 h at the concentration as low as 0.625 μmol/L was sufficient to reduce the viability of H1688 cells. Treatment of the cells with 20 μmol/L END or EAD significantly lowered the cell viability to 16.45% (P=0.000) and 61.20% (P=0.046) at 24 h, to 9.10% (P=0.000) and 43.37% (P=0.000) at 48 h, and to 5.24% (P=0.000) and 29.55% (P=0.000) at 72 h, respectively; the viability of EVO-treated cells was 60.81% (P=0.038) at 24 h, 21.99% (P=0.000) at 48 h, and 18.51% (P=0.000) at 72 h. Treatments of the cells with 10 μmol/L END and EAD for 24hboth induced obvious cell apoptosis with apoptotic rates of 54.98% (P=0.000) and 19.73% (P=0.029), respectively, and caused cell cycle arrest in G2/M phase in 77.78% (P=0.001) and 77.72% (P=0.001) of the cells, respectively. Treatments with 10 μmol/L END and EAD for 48 h both significantly upregulated the expression of Caspase-9(P=0.011, 0.026), Caspase-12(P=0.031, 0.018), Caspase-3(P=0.002, 0.043) and Cyt C(P=0.023, 0.028) in H1688 cells. END produced stronger effects than EVO in up-regulating caspase-3(P=0.026) and Cyt C(P=0.002); the effects of EAD on caspase family and Cyt C were similar to those of EVO. Conclusion Both of the two derivatives of EVO, END and EAD, and particularly the former, have concentration- and time-dependent antitumor effects against H1688 cells in vitro. Both END and EAD can cause cell cycle arrest in G2/M phase and induce apoptosis of H1688 cells via the mitochondrial pathway.

Keywords

• evodiamine
• nitro evodiamine derivatives
• amino evodiamine derivatives
• small-cell lung cancer
• apoptosis