染色体1pter-p36.21杂合性缺失与瘢痕疙瘩的关系

目的寻找瘢痕疙瘩1pter-36.21中可能存在的肿瘤抑制基因的杂合性丢失(LOH)区域,为发现和定位瘢痕抑制基因提供线索和依据。方法采用聚合酶链反应(PCR)-变性聚丙烯酰胺凝胶电泳技术,对25例瘢痕疙瘩组织和外周静脉血标本进行微卫星分析。结果瘢痕疙瘩组织在所选的位点上的LOH发生率为60%(15/25),明显高于正常对照组织的4%(1/25,P<0.05),在所选的位点上均未发现微卫星不稳定性(MSI)。D1S243位点、D1S468位点、D1S507位点、D1S199位点的LOH发生率分别为28%(7/25)、40%(10/25)、52%(13/25)、12%(3/25),其中D1S243、D1S468、D1S507的LOH发生率比较具有统计学意义(P<0.05)。结论发生在D1S243-D1S468-D1S507位点的LOH存在与瘢痕疙瘩有关的潜在瘢痕抑制基因(SSG),而1pter-36.21上LOH微卫星不稳定性与瘢痕疙瘩发生的关系不大。

Mapping of the loss of heterozygosity for chromosome 1pter-36.21 in keloid

Objective The aim of this study was to investigate the loss of heterozygosity (LOH) on chromosome 1pter-36.21 of keloid in order to locate the deletion areas probably harboring scar suppressor genes. Methods Using polymerase chain reaction ( PCR )-denaturing polyacrylamide gel electropholesis, 25 samples of keloid tissues and peripheral blood were analysized.Results 15 out of 25 samples of keloid tissues exhibited LOH in at least one microsatellite locus. There were deletions at more than one locus of one keloid tissue. No MSI was found. The frequency of LOH was remarkly higher in the keloid tissues (n=25, 15, 60%) than in the normal control samples (n=25, 1, 4%). The frequency of LOH in D1S243,D1S468, D1S507 and D1S199 was as following: (n=25, 7, 28%), (n=25, 10, 40%), (n=25, 13, 52%) and (n=25, 3, 12%). The frequency of LOH in D1S243,D1S468, D1S507 were statistically significant. Conclusion The most common LOH occurred at D1S243-D1S468-D1S507 might imply the existence of potential tumor suppressor gene of a subset of keloid , while MSI on 1pter-36.21 may not a crucial event.