The Magnetic Field Combined With The Preliminary Study Of Cisplatin On The Tumor Cell Line K562 Killing Effect Mechanism

Aim:To investigate the mechanism of the synergistic anticancer effect of static magnetic fields(SMF) with cis-platin(DDP)on human leukemia cells K562.The relative DDP concentration in K562 cells was detected by high performance liquid chromatography(HPLC) when cells were treated by DDP with or without SMF,and explored the relationship between the relative DDP concentration in K562 cells and the cell activity of K562 cells.In order to discuss the relationship between DDP absorption and DNA damage,single cell gel electrophoresis(SCGE,comet assay) assay was used to detect the DNA damage caused by DDP or DDP plus SMF;Peripheral blood lymphocytes was used as control of the normal cell,the result of comet assay was compared with that of K562 cell in order to discuss the differences between normal cell and tumor cells.Methods:1.MTT detection was used to determine the activity of K562 cell treated with DDP on different concentrations and exposed to SMF for 12h;MTT detection was also used to determine the activity trend of K562 cell treated with DDP for 12h,with the presentation of SMF.2.HPLC detection was used to determine the absorption of DDP during the cell was exposed to the SMF;SCGE assay was used to determine the trend of DNA damage of K562 cell that was treated with DDP for 12h,with the presentation of SMF;SCGE assay was also used to determine the differences of DNA damage of Peripheral blood lymphocytes,and the results was compared with the K562 cell that was treated with the same stress factor.Results:(1) MTT detection was used to determine the activity of K562 cell exposed to DDP on different concentrations level and SMF.The result shows that,when treated with DDP,at the concentration below 6μg/mL,whether exposed to the SMF or not,no significant difference was detected;at the concentration of 8μg/mL,no significant difference was detected,but when cell was treated with DDP and SMF,cell activity was significantly inhibited(P＜0.05),such phenomenon was considered as synergistic anticancer effect; (2) In the presence of SMF,when K562 cell was treated with DDP for 12h,cell activity shows continuously reduction.The significant difference was detected when cell was treated for 6h.(3) In the presence of SMF,when K562 cell was treated with DDP for 12h, HPLC detection shows that the absorption of DDP raised continuously,after treatment for 10h the absorption of DDP recede because the integrity of cell membranes was destroyed.(4) In the presence of SMF,when K562 cell was treated with DDP for 12h, SCGE result shows that the damage was gradually accumulated.SMF could promote such kind of damage,but could not promote the accumulation.(5) In the presence of SMF,when K562 cell was treated with DDP for 12h,the damage level of the peripheral blood lymphocytes is lower than K562 cell treated with the same manner.That means the peripheral blood lymphocytes has more tolerance than K562 cell.Conclusion:(1) The results indicate that in the presence of SMF,when K562 cell was treated with DDP for 12h,SMF could prove the absorption of DDP,so as to improve the accumulation of DDP inside the cell and cause serious damage.That may be one of the reasons that could explain the synergistic anticancer effect.(2) In the presence of SMF,when K562 cell was treated with DDP for 12h,SMF promote the damage caused by DDP.Positive correlation could be observed between the DNA damage and DDP absorption.(3) In the presence of SMF,when K562 cell and peripheral blood lymphocytes was treated with DDP for 12h,different damage could be detected;Compared with peripheral blood lymphocytes,serious damage is observed in K562 cell.That means lymphocytes has more tolerance than K562 cell.