The Role And Mechanism Of A Novel 3-Alkenylindol-2-One Compound In Acute Myeloid Leukemia

Background: Acute myeloid leukemia(AML)is malignant hematological cancer characterized by progressive loss of normal hematopoiesis.The level of immature malignant cells is increased derived from primitive hematological stem cells or progenitors which are characterized as the differentiation arrest that occurring in bone marrow,blood.The incidence of AML is increasing that accounts for about 80%of acute leukemia.Meanwhile,AML accounts for the highest percentage(62%)of leukemic deaths of all leukemia subtypes.Although the clinical treatment of AML has made some progress in recent years,the 5-year survival rate for young AML patients is about 67%,while the 5-year survival rate for older patients is less than 25%.Therefore,it is necessary to further understand the molecular mechanism of AML and explore new drug for AML treatment.Recently,the development of epigenetic provides a point for the treatment of malignant tumor.Arginine methylation is a ubiquitous post-translational modification that occurs on both histones and non-histone proteins.It is catalyzed by the protein arginine methyltransferases.There are nine PRMTs(PRMT1-9),and the expression levels of PRMTs are increased in most tumors which correlated with poor prognosis and survival.Therefore,targeting PRMTs shed a new light on anti-cancer.Objective: To investigate the effect and mechanism of compound3-alkenylindol-2-one on acute myeloid leukemia cells through regulating protein arginine methyltransferases.Methods:The anti-proliferation of compound 3-alkenylindol-2-one in vitro was accessed by MTT in commom tumor cell lines.Flow cytometry was used to determin cell cycle and apoptosis.The effects of compound 3-alkenylindol-2-one on m RNA and protein levels of c-Myc and PRMT family(PRMT1-8)were measured by q RT-PCR and Western blot in AML cells.Docking analysis was conducted to understand the binding sites between compound 3-alkenylindol-2-one and PRMTs.In vivo activity of anti-AML was obtained by subcutaneous AML xenograft(solid tumors)and systemic AML xenograft mouse models(non-solid tumors).Results:In vitro the MTT assay showed that compound 3-alkenylindol-2-one selectively suppressed the proliferation of AML cells,with hardly effect on human normal liver cells and human embryonic kidney cells.The flow cytometry determined that compound 3-alkenylindol-2-one induced cell arrest in S phase and apoptosis in a concentration-dependent manner.The compound 3-alkenylindol-2-one significantly decreased the expression of oncogenes c-Myc,PRMT1/PRMT4/PRMT5/PRMT7 and the accumulation of histone markers ADMA(H4R3me2a)、SDMA(H4R3me2s and H3R8me2s)in human AML cells.Docking analysis showed that the compound3-alkenylindol-2-one had potential binding sites with PRMT1,PRMT4,PRMT5 and PRMT7 proteins.In vivo,the compound 3-alkenylindol-2-one(30 mg/kg,intragastrical administration)could significantly reduce the growth of subcutaneous AML xenograft(solid tumors)and systemic AML xenograft mouse models(non-solid tumors)with inhibitory rates of 76.21% and 70.24%,respectively.Meanwhile,no siginificant changes were observed in mouse model body weight and major organs.Conclusion:The compound 3-alkenylindol-2-one can selectively inhibit the growth of human AML cells in vitro and in vivo via decreasing the expression of oncogenes c-Myc,PRMT1/PRMT4/PRMT5/PRMT7 and the accumulation of ADMA(H4R3me2a)、SDMA(H4R3me2s and H3R8me2s).The compound 3-alkenylindol-2-one could induce cell cycle arrest and apoptosis in AML cells.In addition,the compound3-alkenylindol-2-one was “druggable” that there is no additional toxicity based on no siginificant changes in mouse model body weight and major organs.