[Effect of Emodin Derivative E11 on T Lymphocytic Leukemia Cell Line Molt-4 and Its Possible Mechanisms].

OBJECTIVE: To explore the effect of a new emodin derivative E11 on proliferation and apoptosis of T lymphocytic leukemia cell line Molt-4 and its possible mechanisms. METHODS: MTT method was used to plot cell growth curve. Colony culture assay was performed for studying the effect of emodin derivative E11 on colony-formation of Molt-4. The fluorescent microscopy with DAPI staining was used to examine the cell morphological changes after E11 treatment. DNA fragmentation method was used to detect the inducing effect of emodin derivative E11 on cell apoptosis. Western blot was used to determine the expressions of apoptosis-related proteins including procaspase-9, procaspase-3, PARP and PI3K/AKT, MAPK signalling pathway. RESULTS: Emodin derivative E11 could strongly inhibit the growth of Molt-4 with the IC50 in 48 h at 1.381 ± 0.1552 µmol/L in dose-dependent manner. 0.1 µmol/L of E11 could inhibit cell colony formation. The typrical apopototic morphologic changes of Molt cells treated with E11 could be observed under fluorescence microscope with DAPI staining. DNA apoptotic ladder could be observed by DNA fragmentation.The expressions of procaspase -9, procaspase-3, PARP, p-MAPK, p-AKT, mTOR, p-mTOR, p-P70 and p-4BEP1 were down-regulated, while expressions of MAPK, AKT, 4EBP1 and P70 were not changed remarkably after Molt-4 were treated with E11 for 48 h. CONCLUSION: E11 can remarkably inhibit the proliferation and induce the apoptosis of Molt-4 cells. The mechanism of apoptosis of Molt-4 cells may be related with the suppression of PI3K/AKT and MAPK signalling pathways.

[Synthesis of emodin derivatives and their inhibiting effects on proliferation of leukemia cell lines].

The aim of this study was to explore the inhibitory effect of newly synthesised emodin derivatives on the proliferation of leukemia cell lines and to select the most effective one from these emodin derivatives for further research. Emodin derivatives were synthesized by modifying the structure of emodin. MTT method was used to detect the proliferative inhibition in leukemia cell lines treated with emodin derivatives. The results showed that the half inhibitory concentration (IC50) for K562 cells treated with emodin derivatives E10-19 for 48 h was 0.84 - 12.01 µmol/L. E19 displayed the best anti-proliferative activity, while E16 and E17 did not show effects on K562 cells. Emodin derivative E19 was chosen for treating U937, NB4, Molt-4 and CA-46 cells, their IC50 for 48 h were 0.85, 0.9, 0.76, 0.8 µmol/L respectively. The IC50 of E19 for LQ2 cells was 3.60 µmol/L, and the IC50 range of E19 for normal human peripheral blood mononuclear cells at 48 h was 4.01 - 4.78 µmol/L. It is concluded that emodin derivative E19 can strongly inhibit the growth of leukemia cells and its inhibiting effect on proliferation of leukemia cells has a certain specificity. The specific mechanism of E19 anti-leukemia effect should be further studied.