Schwartz Friederike H, Cai Qian, Fellmann Eva, Hartmann Sylvia, Mäyränpää Mikko I, Karjalainen-Lindsberg Marja-Liisa, Sundström Christer, Scholtysik René, Hansmann Martin-Leo, Küppers Ralf
Institute of Cell Biology (Cancer Research), University of Duisburg-Essen, Medical School, Essen, Germany.
Dr Senckenberg Institute of Pathology, Goethe-University of Frankfurt, Medical School, Frankfurt, Germany.
J Pathol. 2017 Jun;242(2):129-133. doi: 10.1002/path.4898. Epub 2017 May 3.
Angioimmunoblastic T-cell lymphomas (AITLs) frequently carry mutations in the TET2 and IDH2 genes. TET2 mutations represent early genetic lesions as they had already been detected in haematopoietic precursor cells of AITL patients. We show by analysis of whole-tissue sections and microdissected PD1 cells that the frequency of TET2-mutated AITL is presumably even higher than reported (12/13 cases in our collection; 92%). In two-thirds of informative AITLs (6/9), a fraction of B cells was also TET2-mutated. Investigation of four AITLs by TET2 and IGHV gene sequencing of single microdissected B cells showed that between 10% and 60% of polyclonal B cells in AITL lymph nodes harboured the identical TET2 mutations of the respective T-cell lymphoma clone. Thus, TET2-mutated haematopoietic precursor cells in AITL patients not only give rise to the T-cell lymphoma but also generate a large population of mutated mature B cells. Future studies will show whether this is a reason why AITL patients frequently also develop B-cell lymphomas. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
血管免疫母细胞性T细胞淋巴瘤（AITL）常常携带TET2和IDH2基因的突变。TET2突变代表早期遗传损伤，因为它们已在AITL患者的造血前体细胞中被检测到。通过对全组织切片和显微切割的PD1细胞进行分析，我们发现TET2突变的AITL的频率可能甚至高于报道的频率（我们收集的病例中有12/13例；92%）。在三分之二的可提供信息的AITL（6/9）中，一部分B细胞也发生了TET2突变。通过对单个显微切割的B细胞进行TET2和IGHV基因测序，对4例AITL进行研究，结果显示AITL淋巴结中10%至60%的多克隆B细胞携带与各自T细胞淋巴瘤克隆相同的TET2突变。因此，AITL患者中TET2突变的造血前体细胞不仅产生T细胞淋巴瘤，还产生大量突变的成熟B细胞。未来的研究将表明这是否是AITL患者经常也会发生B细胞淋巴瘤的一个原因。版权所有© 2017英国和爱尔兰病理学会。由约翰·威利父子有限公司出版。
