获得性再生障碍性贫血体细胞突变及其意义

Somatic Mutations of Acquired Aplastic Anemia

再生障碍性贫血(AA)与骨髓增生异常综合征(MDS)都是造血干细胞(HSC)异常的克隆性疾病,两者有时难以区分。随着分子检测技术的进步,人们对两者发病机制的认识也在不断深入。本文将综述AA体细胞突变(SM)与细胞遗传学改变特点,分析其与MDS的分子联系以及在疾病转化中的作用。AA中最常见的体细胞性改变是PIGA和人类白细胞抗原(HLA)等位基因的缺失,它们及8三体、del(13q)与AA免疫发病机制相关。AA最常见的5个突变中,PIGA和BCOR/BCORL1突变预后更好,而DNMT3A和ASXL1突变与克隆演变和预后不良相关。AA继发MDS的危险因素包括预后不良的SM和细胞遗传学改变[如del(7q)]、疾病持续时间较长、AA发病年龄、端粒磨损等。因SM动态变化及意义未确定,其在疾病进展中的意义仍不明,但监测SM并结合临床评估预后仍可能指导治疗。

Aplastic anemia(AA)and myelodysplastic syndrome(MDS)are clonal diseases with hemopoietic stem cell(HSC)abnormalities,which are sometimes difficult to be distinguished from each other.The development of molecular detection techniques has facilitated our understanding of the molecular pathogenesis of the two diseases.This article reviewed the somatic mutation(SM)and cytogenetic changes of AA,and analyzed their molecular relationship with MDS and their roles in disease transformation.The most common somatic change in AA is the loss of PIGA and HLA alleles,which,along with trisomy 8 and del(13q),is related to the immune pathogenesis of AA.Among the 5 most common mutations in AA,PIGA and BCOR/BCORL1 mutations are related to a good prognosis,while DNMT3A and ASXL1 mutations are likely associated with clonal evolution and a poor prognosis.The risk factors for secondary MDS after AA include SM and cytogenetic changes such as del(7q)associated with poor prognosis,prolonged disease duration after diagnosis,onset age of AA,and leukocyte telomere attrition.Although role of SM in disease progression remains unclear because of its dynamic change and unknown significance,prognostic assessment based on the monitoring of SM and clinical features may guide the treatment.