Ethanolic extract of Euphorbia Gypsicola induces differentiation and apoptosis in human myeloid leukemia K562 cells

Introduction

The Euphorbiaceae family, widely distributed and long utilized in traditional medicine, has been recognized for its potential in developing anti-cancer drugs. The current study investigates the capacity of Euphorbia gypsicola extract to induce apoptosis and differentiation in the human myeloid leukemia K562 cell line.

Methods

Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptotic activity was visually evaluated through acridine orange/ethidium bromide (AO/EB) dye staining and annexin V/PI double labeling procedures. Induction of differentiation was examined using nitro blue tetrazolium (NBT) reduction and Wright-Giemsa staining assays. The expression of apoptosis-related proteins including Bax, Bcl2 and Survivin was evaluated by western blotting method.

Results

The E. gypsicola extract exhibited potent medication properties with IC₅₀ values of 207.59, 48.58, and 7.08 ng/mL at 24, 48, and 72 h, respectively. Fluorescence microscopy, DNA fragmentation, annexin V/PI double staining, and sub-G1 cell cycle arrest confirmed apoptosis occurrence in K562 cells treated with the E. gypsicola extract. Our findings demonstrated that differentiated cells reduced NBT yellow solution after endocytosis, forming dark crystals. Wright Giemsa staining observations indicated a decrease in nuclear volume-to-cytoplasm ratio in K562 cells treated with the crude extract, signifying Induction of differentiation. Furthermore, western blot analysis revealed down-regulation of Survivin protein expression and up-regulation of Bax protein level following treatment with the E. gypsicola extract. However, no significant decrease in Bcl2 protein expression level was observed in K562 cells.

Conclusion

These findings indicate the growth inhibitory effects of the E. gypsicola extract on leukemia K562 cells, which supports the further study of this plant to discover novel therapeutic compounds for the treatment of leukemia.