The Research On Effect And Mechanism Of AG490 On Cell Growth Of Chronic Myeloid Leukemia Cells

Object:The incidence of Chronic Myeloid leukemia is 1/100 000, for adult leukemia 15%~20%, its main characteristic is a distinctive t(9; 22)(q34; q11) chromosome translocation (Ph) and the BCR - ABL fusion gene. At present imatinib,the molecular target therapy drug of BCR - ABL tyrosine kinase has become the first CML drug treatment, the five year survival of whose application of IM in chronic-phase is more than 85%, however, with the tyrosine kinase inhibitors using in clinical , the drug resistance and the recurrence rate increase gradually, it has a serious effect of the CML treatment. Many researches find that BCR - ABL gene can activate many signaling pathways, mainly including RAS-MAPK,PI3K and JAK-STAT pathways. For the choice of treatment in Imatinib-resistant patients, it has become research focus to inhibit BCR - ABL downstream signaling pathways at home and abroad. In experiments, we choose AG490 and AKT gene as the research object, this will provide theory basis for the CML new drug treatment. Methords: We used 50μmol/l,75μmol/l,100μmol/l as the end concentration of AG490, the K562 cell lines and 32Dp210 cell lines were cultured with different concentration of AG490 about 24h,48h,72h,and 32Dp210-T315I cell lines about 6h,12h,24h, Methyl thiozolyl tetrazolium (MTT) was used to observe the growth suppressive rate of these cells. Then we put these three cells in different concentration of AG490 about 6h (32Dp210 and 32Dp210- T315I) or 16h(K562), Western blot was used to detection the expression of AKT and p - AKT protein,Results:We showed that AG490 had inhibition effect of K562,32Dp210 and 32Dp210-T315I cells, with the increase of concentration and time, the inhibition rate increased, the inhibition rate was obviously a dose-response relationship, and AG490 had more significant inhibition to 32Dp210 - T315I cells. We found that AG490 could inhibite the phosphorylation of AKT,.With the increase of AG490 concentration, the expression of p - AKT protein gradually reduced and AKT protein had not obvious changes. The experiment proved that the Jak2 inhibitors, AG490, could inhibit the proliferation of CML cells with time and dose-response, it had obverious dependence of imatinib drug-resistant cells, AG490 could inhibite the phosphorylation of AKT,the inhibition effect of AG490 might be through inhibiting the phosphorylation of AKT to play a role. The experiment provided theoretical support and experimental basis for the new treatments of CML.In the future.Conclusion: 1. AG490 could inhibit the growth of K562,32Dp210 and 32Dp210-T315I cells, the inhibition effect was time and dose-response relationship, and AG490 had a more significant inhibition to 32Dp210 - T315I cells.2. AG490 could inhibite the phosphorylation of AKT,.With the increase of AG490 concentration, the expression of p - AKT protein gradually reduced and AKT protein had not obvious changes.3.We supposed that AG490 could inhibite the cell growth due to inhibiting the phosphorylation of AKT.