背景:急性髓性白血病(AML)是一种复杂且异质性的造血干细胞和祖细胞恶性肿瘤,其特征是未成熟的原始细胞在骨髓中积累,血,和其他与环境有关的器官,遗传,和表观遗传因素。基因DNA(胞嘧啶-5)-甲基转移酶3A(DNMT3A;NM_022552.4)中的体细胞突变在AML患者中是常见的。
方法:在本研究中,我们使用Sanger测序检测61名伊拉克AML患者的DNMT3A基因突变,因此,使用各种计算工具鉴定和分析了改变中的蛋白质功能和稳定性,目的是确定这些变化如何影响总蛋白质的稳定性。然后通过甲基化特异性PCR分析CpG岛的MSP状态。
结果:在14例患者中发现了DNMT3A外显子23的三个新突变(22.9%;V877I,N879delA,和L888Q)。V877I和L888Q取代是由杂合C2629G>A和C2663T>A突变引起的,分别,而移码突变C2635delA导致终止密码子N879T*蛋白截短。MSP检测到9例携带DNMT3A突变(64.28%)的DNMT3A启动子区发生甲基化,我们发现DNMT3A突变与启动子甲基化之间存在显着相关性(p=8.52×105)。此外,我们发现,在≥50岁的患者中,DNMT3A甲基化状态显著过度表达(p=0.025).
结论:我们的研究结果强调了研究DNMT3A甲基化改变在伊拉克人群中除白血病通路中的R882取代之外的影响的重要性,以便可以调整患者治疗以防止治疗耐药性和复发。
BACKGROUND: Acute myeloid leukaemia (AML) is a complex and heterogeneous hematopoietic stem and progenitor cell malignancy characterised by the accumulation of immature blast cells in the bone marrow, blood, and other organs linked to environmental, genetic, and epigenetic factors. Somatic mutations in the gene DNA (cytosine-5)-methyltransferase 3A (DNMT3A; NM_022552.4) are common in AML patients.
METHODS: In this study, we used Sanger sequencing to detect the mutations in the DNMT3A gene in 61 Iraqi AML patients, Hence, the protein function and stability within alterations were identified and analyzed using a variety of computational tools with the goal of determining how these changes affect total protein stability, and then the capacity of methylation was analyzed by methylation specific PCR MSP status at CpG islands.
RESULTS: Three novel mutations in exon 23 of DNMT3A were identified in 14 patients (22.9%; V877I, N879delA, and L888Q). The V877I and L888Q substitutions are caused by heterozygous C2629G > A and C2663T > A mutations, respectively, while frameshift mutation C2635delA caused protein truncation with stop codon N879T*. Methylation was detected in the DNMT3A promoter region in 9 patients carrying DNMT3A mutations (64.28%) by MSP, and we found significant correlations between DNMT3A mutations and promoter methylation (p = 8.52 × 105). In addition, we found a significant overrepresentation of DNMT3A methylation status in patients ≥ 50 years old (p = 0.025).
CONCLUSIONS: Our findings highlight the importance of studying the effects of DNMT3A methylation alteration in Iraqi populations beyond R882 substitutions in the leukemogenic pathway so that patient treatment can be tailored to prevent therapeutic resistance and relapse.