Influence Of Chidamide On The Cell Acitivity Of K562 Cells Targeting Cell NK And Its Mechanism In Vitro

Objective:Myeloid leukemia is a malignant proliferative disease.Combined chemotherapy and hematopoietic stem cell transplantation were the main treatment methods.Although progress has been made in terms of efficacy,drug resistance after chemotherapy and relapse after remission have not been well addressed,which is also one of the main factors affecting the prognosis of patients.In rencent years,Cellular immunotherapy has gradually become an important direction of medical development.And Nk cellular therapy is one of cellular immunotherapy.Although Nk cells can be used in the treatment of myeloid leukemia,their efficacy remains to be further improved.therefore,how to further improve the efficacy of Nk cells need to be further investigated.The aim of this study was todiscuss the possibility of increasing the therapeutic efficiency of Nk cells killing myeloid leukemia by Nk cells in vitro through the chidimide co-culture andto further investigate its mechanism.Method:Extraction of peripheral blood from healthy volunteers and isolation of peripheral blood mononuclear cells,cultured in vitro and identificated NK cell purity..The apoptosis rate of k562 cells was detected by flow cytometry after NK cells co-culture with k562 cells pretreated with chidimide by different effctor target ratio(2:1,1:1,0.5:1).Pre-treated NK cells with chidimide for 24 h,co-culture with K562 cells for different effector target ratio(2:1,1:1,0.5:1),Detection of apoptosis rate of k562 cells by flow cytometry.Different concentrations of chidimide were incubated with k562 cells for 72 hours,the level of ULBP1?ULBP2?MICA/MICB expression on K562 cell were assessed by flow cytometry.Results:Chidimide has no cytotoxic effect on k562 cells and NK cells(P>0.05).There was no effect on the killing function of NK cells after co-culture with chidimide with NK cells.The killing effect of NK cells could be increased by co-culture of chidimide with k562 cells(p <0.05).While chidimide significantly upregulates the expression of ULBP2 on the surface of k562 cells(p <0.05),but has no significant effect on ULBP1,MICA/MICB(p >0.05).Conclusion: Chidimide can effectively increase the sensitivity of k562 cells to kill NK cells,which may be related to the upregulation of ULBP2 expression on the surface of k562 cells.This result suggests that combination with chidimide may help further enhance the efficacy of NK cells in myeloid leukemia...