Department of Cellular and Molecular Medicine, University of California San Diego.
University of California San Diego, Moores Cancer Center.
Curr Opin Hematol. 2022 Jan 1;29(1):1-7. doi: 10.1097/MOH.0000000000000688.
Clonal hematopoiesis of indeterminate potential (CHIP), defined by the presence of somatic mutations in hematopoietic cells, is associated with advanced age and increased mortality due to cardiovascular disease. Gene mutations in DNMT3A and TET2 are the most frequently identified variants among patients with CHIP and provide selective advantage that spurs clonal expansion and myeloid skewing. Although DNMT3A and TET2 appear to have opposing enzymatic influence on DNA methylation, mounting data has characterized convergent inflammatory pathways, providing insights to how CHIP may mediate atherosclerotic cardiovascular disease (ASCVD).
We review a multitude of studies that characterize aberrant inflammatory signaling as result of DNMT3A and TET2 deficiency in monocytes and macrophages, immune cells with prominent roles in atherosclerosis. Although specific DNA methylation signatures associated with these known epigenetic regulators have been identified, many studies have also characterized diverse modulatory functions of DNTM3A and TET2 that urge cell and context-specific experimental studies to further define how DNMT3A and TET2 may nonenzymatically activate inflammatory pathways with clinically meaningful consequences.
CHIP, common in elderly individuals, provides an opportunity understand and potentially modify age-related chronic inflammatory ASCVD risk.
不定潜能的克隆性造血(CHIP)是由造血细胞中的体细胞突变定义的,与心血管疾病导致的高龄和死亡率增加有关。在 CHIP 患者中,DNMT3A 和 TET2 的基因突变是最常见的变异,它们提供了选择性优势,刺激了克隆扩增和髓系偏倚。尽管 DNMT3A 和 TET2 似乎对 DNA 甲基化有相反的酶促影响,但越来越多的数据已经描述了趋同的炎症途径,为 CHIP 如何介导动脉粥样硬化性心血管疾病(ASCVD)提供了见解。
我们综述了大量研究,这些研究描述了 DNMT3A 和 TET2 缺乏在单核细胞和巨噬细胞中导致的异常炎症信号,单核细胞和巨噬细胞在动脉粥样硬化中具有突出作用。尽管已经确定了与这些已知表观遗传调节剂相关的特定 DNA 甲基化特征,但许多研究还描述了 DNTM3A 和 TET2 的多种调节功能,这些功能促使细胞和特定于上下文的实验研究进一步确定 DNMT3A 和 TET2 如何以具有临床意义的方式非酶促激活炎症途径。
CHIP 在老年人中很常见,为了解和潜在地改变与年龄相关的慢性炎症性 ASCVD 风险提供了机会。