老年人食管鳞状上皮化生和不典型增生及腺癌序列微卫星改变

目的评估老年人食管鳞状上皮和化生-不典型增生-腺癌的微卫星变化。方法应用稀释性聚合酶链反应（PCR）方法检测存档手术切除的食管癌标本中的D2S123、D3S1616、D3S1300、BATRII、D5S346、D17S787和D18S61位点微卫星的变化。结果在非稀释DNA中，17例食管鳞状细胞癌和12例腺癌微卫星不稳定性（MSI）的频率分别是52．9％（9例）和41．7％（5例），杂合性丢失（LOH）的频率分别是23．5％（4例）和16．7％（2例），两者差异均无统计学意义（P〉0．05）。在8例食管鳞状上皮和化生-不典型增生-腺癌组织稀释DNA中，MSI和LOH频繁出现，与其非稀释DNA的结果比较，差异均有统计学意义（P〈0．05）。结论MSI和LOH在上述组织中普遍存在，它们可能是食管腺癌发生、发展的早期事件。

Microsatellite alterations in elderly patients with normal esophageal squamous epithelium and metaplasiadysplasia-adenocarcinoma sequence

Objective To assess microsatellite alterations in elderly patients with esophageal squamous epithelium and metaplasia-dysplasia-adenocarcinoma sequence. Methods The presence of microsatellite alterations were evaluated in specimens of esophagea carcinoma at D2S123, D3S1616, D3S1300, BATRII, D5S346, D17S787 and D18S61 loci in elderly patients with esophageal squamous epithelium and metaplasia-dysplasia-adenocarcinoma sequence by polymerase chain reaction(PCR). Results The rates of microsatellite instability (MSI) were 52. 9% (9/17 cases) at undilution DNA in 17 cases with squamous cell carcinoma (SCO and 41.7% (5/12 cases) in 12 cases with adenocarcinoma (ADC). The rates of loss of heterozygosity (LOH) were 23.5% (4/17 cases) in undilution DNA in SCC and 16. 7 % (2/12 cases) in ADC. No significant differences were found in the rates of MSI and LOH at above 7 loci in undilution DNA between SCC and ADC (all P>0. 05). MSI and LOH at above 7 loci were frequent in dilution DNA from 8 cases with esophageal squamous epithelium and metaplasia-dysplasia-adenocarcinoma sequence, especially at D3S1616, D2S123, D3S1300 and D17S787 loci. There were significant differences in the rates of MSI and LOH between dilution DNA and undilution DNA (all P<0. 05). Conclusions MSI and LOH are very common in dilution DNA in elderly patients with esophageal squamous epithelium and metaplasia-dysplasiaadenocarcinoma sequence. MSI and LOH may be early genetic events during esophageal carcinogenesis.