摘要目的 检测霍奇金淋巴瘤(HL)亚型Richter综合征免疫球蛋白重链可变区(IgVH)基因重排、突变、克隆相关性等基因特征及其与预后的关系,初步探讨其可能涉及的分子机制.方法 用基因扫描分析HL亚型Richter综合征及慢性B淋巴细胞性白血病(B-CLL)伴CD30阳性R-S细胞样细胞病例IgVH基因的克隆性重排,测序分析IgVH基因的突变状态及其分子特征;用激光显微切割结合半套式PCR扩增R-S细胞和R-S细胞样细胞的IgVH基因,比较两种肿瘤成分的克隆相关性;用免疫组织化学LAB-SA法检测两种肿瘤中zeta相关蛋白70(ZAP70)、p53、干扰素调节因子4(IRF-4)及EB病毒潜伏膜蛋白-1(LMP1)等因子表达的不同.结果 (1)6例向HL转化及6例向R-S细胞样细胞转化的B-CLL患者中,携带突变型IgVH基因的患者各占5例;(2)4例IgVH基因克隆相关性分析中,与相应B-CLL克隆不相关的2例R-S细胞和1例R-S细胞样细胞表达LMP1.而1例与B-CLL来自相同克隆的R-S细胞样细胞不表达LMP1;(3)HL亚型Richter综合征中B-CLL肿瘤细胞常使用的IgVH基因是VH3和VH4家族,6例中各有2例使用VH4-34和VH3-48基因.结论 (1)转化的HL和R-S细胞样细胞主要与生发中心或生发中心后的B-CLL有关,提示不同类型的Richter综合征可能涉及的发病机制不同;(2)HL与R-S细胞样细胞既可以是B-CLL克隆相关病例,也可以是克隆不相关的病例.而后者可能与B-CLL患者免疫抑制后继发EB病毒感染有关;(3)IgVH基因在HL亚型Richter综合征B-CLL中的偏向性使用,提示抗原在转化中的作用.

abstractsObjective To detect the clonal relationship, the rearrangement, and the mutational status of IgVH gene; the influence of these molecular characteristics on the clinical outcome in Hodgkin variant of Richter syndrome; and the possible molecular pathogenesis in this transformation. Methods The clonal rearrangements and mutational status of IgVH genes were analyzed in Hodgkin variant of Richter syndrome and B-CLL with Reed-Steinberg (R-S) -like cells by GeneScan analysis and sequencing. Semi-nest PCR based on laser capture microdissection was utilized to compare the clonal relationship between B-CLL and R-S/R-Slike cells. Immunohistochemical staining was used to detect the different expressions of ZAP70,p53, IRF-4 and LMP1 in the two components. Results (1) 5/6 B-CLL cases transformed to Hodgkin lymphoma (HL)/R-S-like cells carried the mutated IgVH genes; (2) 2 cases of R-S cells and 1 case of R-S-like cells were clonally distinct from B-CLL clone and express LMPI, whereas 1 case of R-S-like cells was relating to the surrounding B-CLL cells and did not express LMP1; (3) 2/6 B-CLL cases transformed to HLconvey VH4-34 and VH3-48 respectively. Conclusions (1) Richtertransformation to HL/R-S-like cells evolves from the B-CLL which originates from the germinal center or post germinal center B cells,indicating that different lymphoma cells of different subtypes in Richter syndrome come from different B cell lineage and possibly involve a different pathogenesis and pathway; (2) HL and R-S-like cells evolve from either the B-CLL clone or may develop as a clonally unrelated lymphoma, the independent secondary malignancies are appear to be EBV-posifive, possibly as a consequence of the underlying immunodeficiency;(3) The biased usage of IgVH genes suggested a role of antigens involved in the HL variant of Richter syndrome.