Amaç: Peroksizom proliferatör aktive edici reseptör (PPAR) gama; hücresel büyüme, farklılaşma ve apopitozisi düzenleyen nükleer hormon reseptör ailesinin bir üyesidir. Normal kemik iliğinde ve periferik CD34+ hücrelerde PPAR gama ifadesi mevcuttur. Akut miyeloid lösemi (AML)'de bu ifadenin azaldığını gösteren çalışmalar vardır. Ancak, bu azalmanın transkripsiyonel mi yoksa epigenetik mi olduğuna dair çalışma yoktur. Hipotezimiz, AML hastalarında PPAR gama ifadesinin azalmasının, bu gen bölgesinin aşırı metilasyonu sonucu olduğudur. Bu amaca yönelik olarak çalışmamızda, AML ve sağlıklı kontrol grubunda PPAR gama geninin ifadesi ve metilasyon düzeylerini araştırdık. Gereç veYöntemler: Çalışmaya yeni tanı konulmuş 31 AML hastası, 25 sağlıklı birey dâhil edildi. PPAR gama gen ifadesinin farklılığına gerçek zamanlı polimeraz zincir reaksiyonu (RT-PCR) tekniği ile bakıldı. Aynı hastalarda Epitect bisülfit protokolü uygulanarak metilasyon spesifik PCR yapıldı. PPAR gama gen bölgesinde aşırı metilasyon olabilecek promoter bölgesine uygun primerler dizayn edildi. Ardından termal cycler ile bisülfit DNA dönüşümü yapıldı. Epitect HRM PCR protokülü ile PPAR gama genindeki metilasyon düzeyi ölçüldü. Bulgular: RT-PCR sonucunda AML hastalarında PPAR gama gen ifadesinin sağlıklı bireylere göre yaklaşık 1,5 kat kadar azaldığı tespit edildi. PPAR gama ifadesinin azaldığı gösterilen hastalarda metilasyon spesifik PCR ile PPAR gama geni promoter bölgesinin metilasyon durumu incelendiğinde, AML hastalarında aday gen bölgesinde metilasyonun anlamlı olarak arttığı (AML hastalarında %29 ve kontrol grubunda %8, p<0,001) tespit edildi. Sonuç: Çalışmamızda, kemik iliğindeki hematopoetik süreci düzenleyen genlerden biri olan PPAR gama geninin ifadesinin AML hastalarında anlamlı olarak azaldığı izlenmiştir. Bunun yanı sıra, bu gen ifadesinin baskılanmasından, genin promoter bölgesinin aşırı metilasyonunun sorumlu olabileceği gösterilmiştir.
Anahtar Kelimeler: Akut miyeloid lösemi; epigenetik; peroksizom aktive edici reseptör gama
Objective: Peroxisome proliferator activated receptor gamma (PPAR) is a member of the nuclear hormone receptor family that regulates cellular growth, differentiation and apoptosis. PPAR gamma expression is present in normal bone marrow and peripheral CD34+ cells. There are studies showing that this regulation is decreased in acute myeloblastic leukemia (AML). However, there is no study of whether this reduction is transcriptional or epigenetic. For this purpose we investigated the expression and methylation levels of the PPAR gamma gene in AML and healthy control group. Material and Methods: Thirty-one newly diagnosed cases of AML and 25 healthy individuals were included in the study. Differences in the PPAR gamma gene expression between the study group and the control group were analyzed by real time polymerase chain reaction (RT-PCR) technique. Methylation-specific PCR was performed using the Epitect bisulfite protocol. After primers were designed, bisulfite DNA transformation was performed. The methylation level of the PPAR gamma gene was measured by the Epitect HRM PCR protocol. Results: As a result of RT-PCR, the expression of PPAR gamma gene in AML cases was found to be reduced by about 1.5 times compared to healthy individuals. When the methylation status of the PPAR gamma promoter region was examined by methylation-specific PCR in the cases where the PPAR gamma expression was decreased, methylation in the candidate gene region in AML cases was significantly increased (29% in AML cases and 8% in control group, p<0.001). Conclusion: In our study, the expression of the PPAR gamma gene was significantly reduced in patients with AML. It has also been shown that over-methylation of the promoter region may be responsible for suppression of this gene expression.
Keywords: Acute myeloid leukemia; epigenetic; peroxisome proliferator activated receptor gamma
- Steffen B, Muller-Tidow C, Schwable J, Berdel WE, Serve H. The molecular pathogenesis of acute myeloid leukemia. Crit Rev Oncol Hematol. 2005;56(2):195-221. [Crossref] [PubMed]
- Corces-Zimmerman MR, Hong WJ, Weissman IL, Medeiros BC, Majeti R. Preleukemic mutations in human acute myeloid leukemia affect epigenetic regulators and persist in remission. Proc Natl Acad Sci U S A. 2014;111(7):2548-53. [Crossref] [PubMed] [PMC]
- Sasca D, Huntly BJ. Independence of epigenetic and genetic diversity in AML. Nat Med. 2016;22(7):708-9. [Crossref] [PubMed]
- Figueroa ME, Lugthart S, Li Y, Erpelinck-Verschueren C, Deng X, Christos PJ, et al. DNA methylation signatures identify biologically distinct subtypes in acute myeloid leukemia. Cancer Cell. 2010;17(1):13-27. [Crossref] [PubMed] [PMC]
- Mehdipour P, Santoro F, Minucci S. Epigenetic alterations in acute myeloid leukemias. FEBS J. 2015;282(9):1786-800. [Crossref] [PubMed]
- Wouters BJ, Delwel R. Epigenetics and approaches to targeted epigenetic therapy in acute myeloid leukemia. Blood. 2016;127(1):42-52. [Crossref] [PubMed]
- Lagunas-Rangel FA, Chavez-Valencia V, Gomez-Guijosa MA, Cortes-Penagos C. Acute myeloid leukemia-genetic alterations and their clinical prognosis. Int J Hematol Oncol Stem Cell Res. 2017;11(4):328-39.
- Dores GM, Devesa SS, Curtis RE, Linet MS, Morton LM. Acute leukemia incidence and patient survival among children and adults in the United States, 2001-2007. Blood. 2012;119(1):34-43. [Crossref] [PubMed] [PMC]
- Kayser S, Dohner K, Krauter J, Kohne CH, Horst HA, Held G, et al. The impact of therapy-related acute myeloid leukemia (AML) on outcome in 2853 adult patients with newly diagnosed AML. Blood. 2011;117(7):2137-45. [Crossref] [PubMed]
- Tabe Y, Konopleva M, Andreeff M, Ohsaka A. Effects of PPARgamma ligands on leukemia. PPAR Res. 2012;2012:483656. [Crossref] [PubMed] [PMC]
- Asou H, Verbeek W, Williamson E, Elstner E, Kubota T, Kamada N, et al. Growth inhibition of myeloid leukemia cells by troglitazone, a ligand for peroxiome proliferator activated receptor gamma, and retinoids. Int J Oncol. 1999;15(5):1027-31. [Crossref] [PubMed]
- Tsao T, Kornblau S, Safe S, Watt JC, Ruvolo V, Chen W, et al. Role of peroxisome proliferator-activated receptor-gamma and its coactivator DRIP205 in cellular responses to CDDO (RTA-401) in acute myelogenous leukemia. Cancer Res. 2010;70(12):4949-60. [Crossref] [PubMed] [PMC]
- Konopleva M, Elstner E, McQueen TJ, Tsao T, Sudarikov A, Hu W, et al. Peroxisome proliferator-activated receptor gamma and retinoid X receptor ligands are potent inducers of differentiation and apoptosis in leukemias. Mol Cancer Ther. 2004;3(10):1249-62.
- Braissant O, Foufelle F, Scotto C, Dauca M, Wahli W. Differential expression of peroxisome proliferator-activated receptors (PPARs): tissue distribution of PPAR-alpha, -beta, and -gamma in the adult rat. Endocrinology. 1996;137(1):354-66. [Crossref] [PubMed]
- Garcia-Bates TM, Lehmann GM, Simpson-Haidaris PJ, Bernstein SH, Sime PJ, Phipps RP. Role of peroxisome proliferator-activated receptor gamma and its ligands in the treatment of hematological malignancies. PPAR Res. 2008;2008:834612. [Crossref] [PubMed] [PMC]
- Ulivieri C, Baldari CT. The potential of peroxisome proliferator-activated receptor gamma (PPARgamma) ligands in the treatment of hematological malignancies. Mini Rev Med Chem. 2007;7(9):877-87. [Crossref] [PubMed]
- Ikezoe T, Miller CW, Kawano S, Heaney A, Williamson EA, Hisatake J, et al. Mutational analysis of the peroxisome proliferator-activated receptor gamma gene in human malignancies. Cancer Res. 2001;61(13):5307-10.
- Padilla J, Kaur K, Harris SG, Phipps RP. PPAR-gamma-mediated regulation of normal and malignant B lineage cells. Ann N Y Acad Sci. 2000;905:97-109. [Crossref] [PubMed]
- Padilla J, Kaur K, Cao HJ, Smith TJ, Phipps RP. Peroxisome proliferator activator receptor-gamma agonists and 15-deoxy-Delta(12,14)(12,14)-PGJ(2) induce apoptosis in normal and malignant B-lineage cells. J Immunol. 2000;165(12):6941-8. [Crossref] [PubMed]
- Fujimura S, Suzumiya J, Nakamura K, Ono J. Effects of troglitazone on the growth and differentiation of hematopoietic cell lines. Int J Oncol. 1998;13(6):1263-7. [Crossref] [PubMed]
- Zhao Q, Fan YC, Zhao J, Gao S, Zhao ZH, Wang K. DNA methylation patterns of peroxisome proliferator-activated receptor gamma gene associated with liver fibrosis and inflammation in chronic hepatitis B. J Viral Hepat. 2013;20(6):430-7. [Crossref] [PubMed]
- Fujiki K, Kano F, Shiota K, Murata M. Expression of the peroxisome proliferator activated receptor gamma gene is repressed by DNA methylation in visceral adipose tissue of mouse models of diabetes. BMC Biol. 2009;7:38. [Crossref] [PubMed] [PMC]
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