The Role Of Histone Acetyltransferase MOF In Acute Myeloid Leukemia

AML(Acute Myeloid Leukemia)is a hematologic malignancy that occurs in adults,commonly.In China,it has high morbidity,high mortality,poor prognosis.At present,the treatment of AML to drug-based chemotherapy,the most classical treatment for cytarabine and daunorubicin combination therapy.Although this method can control AML,extend patient survival,due to the drugs,easy to make tumor cells produce MD(Multidrug Resistance).Because of the drug effect to tissues and organs,the recurrence of AML may produce TRL(Therapy Related Leukemia).Therefore,to find an effective therapeutic target,the development of targeted drugs will be the best way to treat AML.In recent years,epigenetic modification as a hot topic in the study of tumorigenesis,development and treatment,there are a variety of epigenetic molecular targeted drugs for the treatment of cancer clinical application,but there is no clearly research results for AML.Therefore,the epigenetic regulation in the study of AML is still significant.MOF,also known as KAT8 or MYST1,is a member of the MYST family of histone acetyltransferases that specifically acetylates H4K16.MOF also acetylates non-histones such as:P53,Nrf2 and so on.MOF plays an important role in embryonic development,cell differentiation,tumorigenesis,DNA damage and other life activities.Research purposes:By analyzing and comparing bone marrow samples from AML patients and normal donors,the MOF expression was determined;U937 and THP1 two AML cell lines as the research object,use of cytarabine stimulation,to determine MOF expression trends and experimental optimum time and dose;Change the MOF expression level in cells,observe the changes of cell survival rate and apoptosis rate after stimulation with cytarabine;The changes of the expression of MOF and Nrf2 in U937 resistant cells and the expression of Nrf2 downstream molecules were compared and analyzed.The cells were treated with cytidine acetylation inhibitor MG 149 and cytarabine simultaneously to observe the changes of cell viability.Research methods:1.The MOF RNA levels in clinical samples were determined by RT-PCR.2.Different concentration gradients were set separately,and two kinds of AML cells,U937 and THP1,were treated with cytarabine.Cell viability was measured by CCK-8 at different concentrations,a concentration gradient was set around the IC50 concentration,western blot was used to detect the changes of MOF after cytarabine treatment.3.Construction of knockdown or overexpression MOF plasmid,transiently transfected cells,detection apoptosis and cycle related protein changes by knockdown MOF;Knockdown or overexpression MOF in cells treatment with cytarabine,the apoptosis rate of the cells was detected by flow cytometry.the cell viability was measured by CCK-8 and the IC50 value was calculated.4.U937 resistant cells were screened by increasing the concentration of cytarabine.The changes of MOF,Nrf2 RNA were detected and the changes of RNA molecules downstream of Nrf2 were detected.5.U937 and THP1 were treated with MG 149 and cytarabine to detect the changes of MOF protein,the level of apoptosis and the survival rate.The cell viability was detected by using MG 149 and cytarabine in U937 resistant cells.Results:1.Compared and analysis of clinical samples,in the bone marrow samples of AML patients,MOF expression levels higher than the normal donor levels.2.After stimulated with cytarabine,MOF expression in U937 and THP1 cells gradually decreased with increasing concentration.3.In U937 cells,knockdown MOF and use cytarabine treatment of cells,will increase the le'vel of apoptosis,cell survival decreased;over-expression MOF and use cytarabine treatment of cells,will reduce apoptosis Level,cell survival rate increased.4.The expression of MOF and Nrf2 in U937R cells is higher than that in U937 cells.The stronger the cell resistance was,the higher expression of MOF was and the higher expression of Nrf2 was down-regulated in drug-resistant cells.5.MG 149 can effectively inhibit the acetyltransferase activity of MOF,combined with cytarabine to stimulate cells,the level of apoptosis increased,the survival rate decreased;U937 drug-resistant cells,MG 149 will reduce the cytarabine IC50 value.Conclusion:MOF plays an important role in AML,MOF has a protective effect on AML cells.In the treatment of cells with drugs,low expression of MOF will increase the level of cell damage,over-expression of MOF will make the damage caused by the drug has been restored.In drug-resistant cells MOF levels higher than non-drug-resistant cells,the use of MG149 will reduce cell resistance.