The Expression And Regulatory Mechanism Of MiR-21in Diffuse Large B Cell Lymphoma

Objectives To evaluate the expression levels of miR-21in DLBCL by studing on DLBCL tumor tissue and DLBCL cell line CRL-2630,and analyze the relationship between the expression level of miR-21in patients and its clinical features to provid information for clinical diagnosis and prognosis of DLBCL. Assessing the tumor cell apoptosis through downregulation of miR-21in DLBCL cell lines CRL-2630,and forecast miR-21as a target of gene therapy for DLBCL.To estimate the relationship between miR-21and pten in tumor tissue and tumor cells and investigate the mechanism of carcinogenicity.Method In chapter one, Real time RT-PCR was used to analyze the miRNA expression level in26DLBCL patients tumor paraffin issuses and10lymph nodes、 DLBCL cell line CRL-2630and normal lymphocyte:Normal lymphocyte were obtained from peripheral blood samples collected from4healthy donors.and analyze In chapter two,we examined the effects of anti-miRNA oligonucleotides (AMOs) targeting miR-21(AMO-21) in DLCBL line which was over-expressing this miRNA, Electroporation was used to transfect AMO-21into cell, Real time RT-PCR and method was used to prove AMO-21’s effect,Armexin-V,flow cytometry assay were used to detcet the CRL-2630cell apoptosis changes and PTEN expression was detected using immunohistochemistry on26DLBCL patients tumor paraffin issuses and10lymph node after knocking down miR-21in vitro.Results (1) The level of miR-21were expressed at significantly (P=.008) higher levels in cancer tissues(2.70(0.13,5.25)) than normal lymph nodes(0.34(1.51,1.39)),expression of that in cancer tissues were on average8.65-fold higher than in normal lymph nodes(P<0.05).,The levels of miR-21was upregulated in tumor line than that in normal lymphocyte.The expression of miR-21from DLBCL patients was positive correlated with the level of serum LDH(p=0.046). The expression miR-21from patients in Ⅲ/Ⅳ stage were significantly higher than Ⅰ/Ⅱ stage patients(p=0.02),there was no correlation between the expression of miR-21and clinical stage.(2) the apoptosis of CRL-2630cells increased when they were exposed to AMO-21for48hours. Conclusion (1) Overexpression of miR-21is considered to be a new molecular marker for DLBCL, it provide evidence for the diagnosis of DLBCL.(2) the expression of miR-21was positive correlated with the level of serum LDH and clinical stage, it might implied that the level of miR-21was a useful marker estimating the prognosis of DLBCL, PTEN maybe a target gene of miR-21。(3) It showed that AMO-21can induce tumor cell apoptosis, antisense oligonucleotide transfetion is an effeetive approach to inhibit overexpressed miRNA and it has optimistic clinic trail prospects.miR-21can be a gene therapeutic target candidate in human DLBCL.