Expression And Role In Regulation Of Autophagy Of Autophagy And Apoptosis Related Gen In Myelodysplastic Syndrome

Objective:Myelodysplastic syndromes(MDS)has a high risk of transform to acute myeloid leukemia(AML).Autophagy has been found to play a role in the pathogenesis and malignant progression of MDS in recent years.Bcl-2 is a classical anti-apoptotic protein and has recently been found to be associated with autophagy.The purpose of this study is to detect the activty of autophagy and the expression of Bcl-2 in bone marrow mononuclear cells of MDS,try to explore the roles of Bcl-2 in autophagy.Methods:1.Using transmission electron microscopy(TEM)to observe autophagy vacuoles and detect the ratio area of vacuoles/cytoplasm of bone marrow mononuclear cells(BMNCs)in patients with hematological diseases.2.Using Quantitative real-time PCR(q RT-PCR)to detect the expression of LC3,Beclin-1 and Bcl-2 m RNA in 73 cases of BMNCs with hematologic disease.3.Using small interfer RNA(si RNA)method to transfect the MDS cell line skm-1 with Bcl-2 specific si RNA(si RNA-Bcl-2),then detect the expression of Bcl-2,LC3 and Beclin-1 m RNA using q RT-PCR and protein using Western-blot.Results:1.TEM confirmed that the level of autophagy in the MDS group was higher than that in the AML group.2.The expression of LC3 B and Beclin1 m RNA was higher in MDS group and lower in AML group.The expression of LC3 B and Beclin1 m RNA was gradually decreased in low-risk MDS group,high-risk MDS group and AML group.3.The expression of Bcl-2 m RNA in BMNCs was higher in AML group than in MDS group,and higher in MDS group than in control group(NC group)(P<0.05).4.After the expression of Bcl-2 was down-regulated by si RNA-Bcl-2,the autophagy factor Beclin-1 was increased.Conclusion:1.The level of autophagy in NM,MDS,AML was negatively correlated with the degree of malignancy of the disease.2.The expression of Bcl-2 increased gradually in NC,low-risk MDS,high-risk MDS and AML,and its expression was positive correlated with the degree of malignancy of the disease.3.Bcl-2 could regulate autophagy through Beclin-1 dependent pathway.