肾母细胞瘤微卫星不稳定性与临床病理的关系

Relationship Between MSI and Clinicopathological Variables in Wilms Tumor

目的:探讨肾母细胞瘤微卫星不稳定性(microsatellite instability,MSI)与临床病理的关系。方法:采用 PCR 扩增、变性聚丙烯酰胺凝胶电泳、银染等技术,选用分别定位于 X 及21号染色体的 AR 和 UT_(762)微卫星标记位点,对50例肾母细胞瘤进行 MSI 测定。结果:AR 位点MSI 阳性14例(28%),UT_(762)位点阳性10例(20%),同一病例两位点均阳性2例(4%),至少一个位点阳性22例(44%)。按 NWTS-Ⅲ临床病理分期,早期肿瘤(Ⅰ、Ⅱ期38例,16例阳性)阳性率42.1%与晚期肿瘤(Ⅲ、Ⅳ期12例,6例阳性)阳性率50.0%间无统计学差异(P>0.05);参照NWTS-Ⅱ病理分期,间变型(14例,阳性10例)阳性率71.4%,显著高于无间变型(36例中12例阳性)阳性率33.3%(P<0.05),并发现2例病理阴性者手术切缘组织 MSI 阳性。结论:MSI 可能是肾母细胞瘤发生的早期事件,并与其恶性程度有关。

Objective:To study the relationship between microsatellite instability(MSI)and clinicopathological variability in Wilms' tumor.Methods:Two repeated microsatellite sequences, AR(chromosome X)and UT_(762)(chromosome 21)were examined in normal and tumor pairs from 50 patients with Wilms' tumor by PCR and other related methods.Results:The MSI from AR and UT_(762)loci was observed in 14/50 and 10/50 respectively on cases with Wilms' tumor.The MSI positive for both AR and UT_(762)in the same case was observed on 2/50,but positive for either AR or UT_(762)on 22/50.According to NWTS-Ⅲ clinicopathological staging,MSI in stage Ⅰ or Ⅱ was observed on 16/38,stage Ⅲ or Ⅳ was 6/12,the difference was not apparent(P>0.05).The difference of MSI between favorable(4/10)and unfavorable histology(12/36)was more apparent (P<0.05).In addition,MSI was observed at the tumor resection margin on 2 cases. Conclusions:MSI may be an early change related to Wilms' tumor and its malignancy.