Study on the Relationship between Autophagy and Apoptosis in A549 Cells Induced by Curcumin Analogue EF24

Abstract: This paper studies the cytotoxicity mechanism of curcumin analogue EF24 in A549 cell line (human lung adenocarcinoma cells) through the relationship between autophagy and apoptosis. After treatment with different concentrations of EF24 in A549 cell line， we used MTT assay to check cell liviability， acridine orange staining to observe cell morphology change， and Western blot to detect cell autophagy and apoptosis-related protein in AMPK-mTOR-S6K signaling pathway. These results showed that the half lethal dose IC50 of EF24 in A549 cell line at 24 h was 8.5 μmol/L， which was more less than curcumin and similar to cisplatin. With the detection of autophagy and apoptosis-related protein， we found that autophagy was a mainly phenomenon at the concentration of 4 μmol/L and 8 μmol/L， however， the apoptosis played an important role at the concentration of 16 μmol/L; Autophagy inhibitor wortmannin (100 nmol/L) could partly increase the cell survival rate. Meanwhile， we also found the increasing phosphorylation level of AMPK-Thr172 and decreasing phosphorylation level of mTOR-Ser2481 and S6K-Thr389 after treatment with EF24. Our results indicate that EF24 inhibited cell growth in A549 cell line through activing AMPK kinase and attenuate the mTOR-S6K pathway. Autophagy promoted cell apoptosis in the concentration range of 4~8 μmol/L EF24.

CSTR: 32200.14.cjcb.2012.06.0009