B细胞淋巴瘤微卫星不稳定性及杂合性缺失的研究

目的:探讨微卫星不稳定性及杂合性缺失在B细胞淋巴瘤发生学上的意义。方法:选取6号染色体上7对多态微卫星标记,结合PCR及银染技术,采用凝胶成像图像分析系统进行分析,分别检测53例B细胞淋巴瘤染色体微卫星不稳定性及杂合性缺失。结果:在位点D6S275MSI的发生率为7.5%(4/53),其中包括2例DLBCL,FL和B-CLL/SLL各1例,LOH总的发生率达66%(35/53),其中包括DLBCL19例(19/21,90.5%),FL8例(8/13,61.5%),B-CLL/SLL8例(8/19,42.1%),DLBCL的LOH率同B-CLL/SLL、FL相比,差异具有统计学意义。结论:位点D6S275可能存在一个抑癌基因,该基因的缺失对B细胞淋巴瘤的发生是否有重要意义有待进一步研究。

The study of loss of heterozygosity and microsatellite instability in B cell lymphoma

Objective To evaluate the significance of the loss of heterozygosity and microsatellite instability in the pathogenesis of B-cell lymphoma. Method LOH and MSI were studied in 53 cases with B-cell lymphomas by means of PCR amplification and silver staining at seven polymorphic microsatellites DNA loci on chromosome six. Results Four cases of lymphoma (including two cases of DLBCL,one case of FL and one of B-CLL/SLL)showed MSI,but thirty five cases of lymphomas(66%,35/53) showed LOH at the locus of D6S275. Molecular genomic change (LOH) at the locus was observed in 90.5% of the DLBCL (19/21),in 61.5%(8/13) of FL and in 42.1% (8/19)of B-CLL/SLL. The frequency of LOH was significantly related to the types of lymphomas(P<0.05).Conclusion There might be a tumor suppressor gene at D6S275 locus and it is to be verified whether it is important to the pathagenesis of B-cell lymphoma or not.