Anti-proliferation Effect Of Methyl Jasmonate Combined With Cisplatin On Osteosarcoma Cells MG-63

Background and Objective:Osteosarcoma is the most common malignant tumor in clinical,the main treatment is surgery plus chemotherapy drugs at present. However,current chemotherapy drugs in this fashion are toxic, often resulting in severe side effects for the patients. Therefore, it is a significant thing that we try to find out the traditional drug which less adverse reaction and the effective pharmacology. Early research found that Methyl jasmonic is common in plants and has important physiological functions which involved in cell growth and development. The present study suggests that MEJA could inhibit a wide variety of tumor cell proliferation and induce its apoptosis. As a consequence, in this experiment we try to explore the Anti-proliferation effect and action mechanism of Methyl Jasmonate (MEJA)combined with Cisplatin (CDDP) on human osteosarcoma cells MG-63.Methods:(1) The experimental points four groups,The blank control group, MEJA group,CDDP group and MEJA + CDDP combined group;(2) MG-63 cells were treated with different concentration gradient MEJA combined with or without CDDP,morphology of the cell was observed by inversion phase contrast microscope;(3) The number of apoptotic cells and the apoptosis rate was determined by Hoechst 33342 nuclear staining and flow cytometry respectively;(4)RT-PCR was performed to measure the mRNA level of Caspase-3 and Bcl-2;Western blotting was used to evaluate the protein levels of cleaved Caspase-3 and Bcl-2.Results:(1) Microscopically,the tumor cells grew normally in control groups,Nevertheless, The different concentration gradient drug groups performed apoptosis states in different degrees , part of the cells fall off and degradation, adherent cell density decreased, partially exfoliated cells turn to round or spindle, the cells spacing increase and the intracellular particles increased, the number of apoptosis cells in two single drug groups were roughly the similar in the identical concentration gradient microscopically, the result of combined group was more prominent and we could certainly found that the above phenomenon was more obvious with the increase of drug concentration;(2)The results of Hoechst 33342 reveal that the tumor cells were dye with uniform light blue fluorescence in the control group,the nuclei were thick dense in single drug groups and we can see so much apoptosis cells which with strong white light, the results of combined group is more distinct;(3)Flow cytometry test results show that the apoptosis rate in blank control grou was 8.18±1.24%,MEJA group was 27.98±2.76%,CDDP group was 31.99±3.6 % and MEJA + CDDP combined group was 45.77±2.76% respectively. The cell apoptosis rate in two single drug groups is higher than control group ,surely the combined group was obviously above the average compared with that of single drug groups and control group;(4)The results of RT-PCR and Western blotting prompt that MEJA and CDDP can significantly increased the levels of Caspase-3,and prevented the increase of Bcl -2 expression, the result of combined group is more remarkable.Conclusion:MEJA combined with CDDP could obtain a cooperative anti-proliferation effect on MG-63 cells and induce its apoptosis, the mechanism may be relate to downgrade the Bcl - 2 and raised the Caspase- 3 expression.