The influence of the tyrosine Kinase inhibitor imatinib mesylate on the cell repair function after DNA damage in K562 cells / 中华检验医学杂志

ABSTRACT

Objeetive To construct the cell DNA damage models for the human CML K562 cell line before or after imarlnib mesylate treatment and observe the repairing process dynamically for investigating the iniluence of imatinib mesylate on the repair function of K562 cells after cell DNA danlage.Methods The MTT assay was used to estimate the optimal pretreatment concentration of imatinib mesylate in K562 cells and Western blot was employed to evaluate the phosphorylation status in K562 cells after imatinib mesylate treatment to estimate BCR/ABL tyrosine kinase inhibition by imatinib mesylate.The comet assay was used to detect the DNA damage induced by hydrogen peroxide at various concentrations in K562 cells with or without the pretreatment of imatinib mesylate.A dynamic observation on the repairing process after cell DNA damage was made by the comet assay.Results The pretreatment by imatinib mesylate for K562 cells was optimized to be at a final concentration of 1 μmol/L for 24 h as revealed by the MTT assay additionly imatinib mesylate treatment at this concentration could effectively inhibit the phosphorylation of the BCR-ABL fusion protein at Tyr177(Deusityrate 0.100±0.018).When compared with the control group(Deusityrate 0.425±0.039),the BCR/ABL phosphorylation at Tyr177 was significantly decreased by (77. 11±5.59) % (t=4. 57,P＜0. 05). The cell DNA damage models for both imatinib mesylate-nontreated and imatinib mesylate-pretreated K562 cell groups were constructed with hydrogen peroxide treatment at a final concentration of 10 μmol/L for 10 min at 4℃ as confirmed by the comet assay. When compared with the control imatinib mesylatenontreatod K562 cell group,the time duration required for the DNA repair in imatinib mesylate-pretreated K562 cell group was significantly prolonged (F= 97.79,P＜0. 05 ). Conclusions The cell DNA damage models for the leukemic K562 cell groups before or after imatinib mesylate treatment were successfully constructed and the tyrosine kinase inhibitor imatinib mesylate for BCR/ABL fusion protein was revealed to attenuate the DNA repair capacity of the K562 cells after DNA damage.