K562 cell cycle arrest in G0/G1 phase by two species of Daphne family

Nowadays, the plant of Daphne family (Thymelaeacea is used against microorganisms and cancerous cells. The purpose of this study was to investigate the effects of two Daphne species and purified betulin and betulinic acid on K562 genome and the cell cycle. This Study was conducted in a complementary randomized design with three replications. 106 K562 cells were treated with Daphne mucronata, Daphne oleides, betulin and betulinic acid for 24 hours. Then, cells were fixed in 70% ethanol and were stained with pripidium iodide 30 min before analysis by flow cytometery. To extract the DNA of cancer cells Miller saline method with little change was used. Data were analyzed with SPSS. version 16 by ANOVA and Dunnett. Percentage of cancer cells that were treated with Daphne mucronata (59.11±1.16%), Daphne oleides (58.25±1.03%), betulin (51.68±0.43%), and betulinic acid (52.05±0.31%) increased in the G0/G1 phase compared to the control (42.94±0.23%). While most percentage the control cells (51.06±0.16%) were present in S phaseElectrophoresis of genomic DNA of K562 cell lines revealed band boarding and smearing under the effect of plant material. However, a clear sharp band of DNA was seen in control samples. The lowest and highest smeared band was observed in treated cells with Betulin and Daphne mucronata, respectively. Data showed that materials and compounds of Daphne, block cells in G1 phase and will cause damage to DNA. In fact, these results indicate that there are several effective factors in two species Daphne extract which damage DNA integrity and inhibit cell transfer from control point and can facilitate cell death at higher concentrations.