MicroRNA-29a Reveals Oncogenic Role on Myeloid Malignancies by Regulating DNMT3A

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1 MicroRNA-29a Reveals Oncogenic Role on Myeloid Malignancies by Regulating DNMT3A Heba Alkhatabi, PhD Assistant Professor Department of Medical Laboratory Collage of Applied Medical science King Abdul Aziz University Laboratory Manger Center of Excellence in Genomic Medicine Research GenaTi

2 Introduction MicroRNAs (mirnas) are a small non-coding RNAs Have been implicated in regulating gene expression Involved in an increasing number of biological processes and.. Play role in regulating normal hematopoiesis.

3 mirna Mechanism

4 MicroRNA Activity in Cancer: Tumor Suppressive or Oncogenic mir Tumor suppressor mir Oncogene

5 mirna Oncogenes or Tumor Suppressor Genes in human Cancer Croce Nat Rev Genet Oct;10(10):704-14

6 Dysregulation of mirna expression in human leukemia, inspiring numerous explorations of the functional role of mirnas in leukemogenesis. Yeh et al. Molecular Cancer (2016) 15:37

7 MicroRNA investigation methods Scientific Reports 6:32493 DOI: /srep32493

8 MiR-29 family (Hwang et al., 2007; Garzon et al., 2009a).

9 mir-29 family members target multiple genes tomediate their biologic effects Garzon et al., 2009b

10 Epigenetic and DNA methyltranferase Epigenetic is defined as The changes in gene expression that are not due to any alteration in the DNA sequence. In humans, DNA is methylated by three enzymes, DNA methyltransferase 1, 3a, and 3b (DNMT1, DNMT3a, DNMT3b). DNMT3a and 3b: are the de novo methyltransferases that set up DNA methylation patterns early in development. DNMT1: is the maintenance methyltransferase that is responsible for copying DNA methylation patterns to the daughter strands during DNA replication. DNA methylation is important in: Transcriptional gene silencing Maintain genome stability Embryonic development Genomic imprinting X chromosome inactivation (females)

11 DNMT3A mutation in hematological malignancies In 2010, DNMT3A mutation was first recognized in association with three groups in acute myeloid leukemia (AML), revealing changes in mutation frequencies for up to 22%. DNMT3A mutations have been reported in several hematological disorders. These mutations are recurrent in AML patients and related to poor event-free and overall survival

12 mir-29a and Epigenetic modulation through DNMT3A Deregulation of microrna-29 (mir-29a/b) family and epigenetic modulating genes as DNMT3a have been associated with the pathogenesis of myeloid leukemia. The down-regulation of mir-29b is thought to promote DNA hypermethylation in AML since mir-29b can directly target DNMT3A, DNMT3B, and DNMT1 via Sp1 (Langemeijer et al., 2009; Tefferi et al., 2009a,b,c; Patel et al., 2012)

13 Research Aims.. Study the expression of mir-29a and DNMT3A as a signature for chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) patients. Address the correlation of mirn-29a and DNMT3A in CML patients with with BCR/ABL in CML patients. The implications of this investigation on the development of mirnadirected therapies in leukemia. The role of mir-29 in regulating epigenetic modifiers, cellular proliferation, apoptosis, and hematopoietic differentiation, and the role of these functional changes in myeloid pathogenesis.

14 Work plan Patients diagnosed with myeleoid leukemia RNA extraction mir-29a expression DNMT3A expression Examine the expression of mirna and target genes in patient samples

15 Research Subjects Control; 5 AML; 11 CML; 11 CML BCR/ABL 1 NO 2 NO 3 B3/a2 4 B3/a2 5 B2/a2 6 B3/a2 7 B2/a2 8 B3/a2 9 B3/a2 10 B2/a2 11 B3/a2 Samples were collected from King AbdulAziz University Hospital Age: The study includes pediatric and adult patients Parients were selcted based on the final diagnosis after all laboratory invistigation completed

16 Result: The Correlation between mir-29a and the target gene DNMT3A in AML and CML patients RQ * * ** 0 Control AML CML mir-29a DNMT3A Presenter s work

17 MiR-29a/ DNMT3A expression mir-29a expression Upregulated Down regulated No change AML 27.27% 54.5% 18.18% CML 27.27% 45.4% 27.27% DNMT3A expression Upregulated Down regulated No change AML % 18.18% CML % 27.27% Presenter s work

18 RQ mir-29a and DNMT3A expression in AML patients AML 3 ** ** ** mir-29a DNMT3A control Presenter s work

19 RQ mir-29a and DNMT3A expression in CML patients CML * * mir-29a DNMT3A control Ph- Ph- Ph+ Ph+ Ph+ Ph+ Ph+ Ph+ Ph+ Ph+ Ph+ - - B3/a2 B3/a2 B2/a2 B3/a2 B2/a2 B3/a2 B3/a2 B2/a2 B3/a2 Presenter s work

20 The correlation between mir-29a expression and CML patients with BCR/ABL fusion Expression profile of 250 mirnas using bone marrow mononuclear cells from patients with Ph+ CML at diagnoses (n = 8). Examined the sample at diagnosis and twelve months after treatment with IM 19 mirnas differentially expressed between resistant and responder samples: 18 of them were downregulated in cluding mir-29a in resistant CML patients.

21 Why the Expression is Low in the Majority of the Cases? Mutation in mir- 29A other Mutation in DNMT3A mir-29a DNMT3A Global hypomthylatio n Treatment

22 DNMT3A sequencing for R882H/S on exons 23 Lin J, Yao Dm, Qian J, Chen Q, Qian W, et al. (2011) Recurrent DNMT3A R882 Mutations in Chinese Patients with Acute Myeloid Leukemia and Myelodysplastic Syndrome. PLOS ONE 6(10): e

23 NGS Sequencing for DNMT3A 48 selected exons in 20 genes found to be commonly mutated in AML. These genes to be associated with myelodysplastic syndromes, myeloproliferative neoplasms. Sequencing using HiSeq/MiSeq. Rapid analysis of raw sequence data for known/predicted pathogenic variants.

24 Epigenetic Inhibitors as Cancer Therapies Cell 150, July 6, 2012 a2012 Elsevier Inc

25 mir-29a as a therapeutic target A role for microrna expression as a prognostic factor in various tumors has only been recently described While no enough information is available regarding their involvement in the response to chemotherapy. Recent studies suggest that mir-15b and mir-16, and mir- 27a and mir-451 modulate multidrug resistance by target-ing BCL2 and MDR1, respectively Research on mice, mir-29a oligonucleotide mimics recapitulate the effects of hypomethylating agents, 5- azacytidine and decitabine, by demethylating the promoters of tumor suppressors estrogen

26 Transplanting mice with HSPCs overexpressing mir- 29a results in increased myeloid and reduced lymphoid chimerism 8 12 weeks post-transplant, and is accompanied by splenomegaly as well as megakaryocytic and granulocytic hyperplasia in the bone marrow and spleen, consistent with a myeloproliferative phenotype. Combinatorial regimens including mir-29 with cytarabine and/or daunorubicin could also help elucidate its therapeutic efficacy as a stimulant of myeloid differentiation in myeloid leukemias.

27 Summary Finally, data demonstrates that.. mir-29a is critical for targeting BCR/ABL1 through its regulation of DNMT3a. Thus, the use of the epigenetic effect via micro RNA or methylation regulated genes may yield clinically useful biomarkers in hematopoietic malignancies.

28 Acknowledgment Dr. Aisha Elaimi Prof. Mohammed Al Qahtani Prof. Adel Abuzenadah Prof. Adeel chudary Prof. Mamdouh Qari Ms. Manal Shabaad Ms. Zinab Allal Ms. Abrar Alqahtani Ms. Hanadi Qudaih Molecular genetic staff Cytogenetic staff Prof. Faten Alsayes Dr. Abeer Hussein Dr. Maha badawi MS.c students Ms. Reham Sultan Mr. Anas Oun