Field J K, Kiaris H, Howard P, Vaughan E D, Spandidos D A, Jones A S
Department of Clinical Dental Sciences, University of Liverpool, UK.
Br J Cancer. 1995 May;71(5):1065-9. doi: 10.1038/bjc.1995.205.
Genomic instability or microsatellite instability (MI) in simple repeated sequences was initially recognised in colonic carcinomas and subsequently in other tumours. MI has been associated with mutations in genes concerned with replication and DNA repair. We investigated 34 microsatellite markers in squamous cell carcinoma of the head and neck (SCCHN). Fifty-six tumours, were studied, of which 25 were investigated with ten or more microsatellite markers. In this study we consider two or more microsatellite alterations in a tumour to be diagnostic of MI. We demonstrated that 7/25 (28%) of the tumours had MI at two or more loci and three of these tumours exhibited evidence of 20 or more loci with MI. No correlations were found between MI and previous treatment, site, histological differentiation, positive nodes at pathology, a history of alcohol intake or survival. MI has been demonstrated in T1N0 stage tumours, indicating that these changes may occur early in the disease process. A negative correlation was found between MI and a history of smoking (P = 0.02). Two or more markers of MI were found in three of four non-smokers compared with one of 13 in the smoking group of patients, which suggests a novel mechanism of carcinogenesis in non-smokers.
基因组不稳定性或简单重复序列中的微卫星不稳定性（MI）最初在结肠癌中被识别出来，随后在其他肿瘤中也被发现。MI与参与复制和DNA修复的基因突变有关。我们研究了头颈部鳞状细胞癌（SCCHN）中的34个微卫星标记。共研究了56个肿瘤，其中25个肿瘤用10个或更多微卫星标记进行了检测。在本研究中，我们将肿瘤中两个或更多微卫星改变视为MI的诊断标准。我们发现，25个肿瘤中有7个（28%）在两个或更多位点存在MI，其中3个肿瘤在20个或更多位点表现出MI证据。未发现MI与既往治疗、部位、组织学分化、病理检查时的阳性淋巴结、饮酒史或生存率之间存在相关性。在T1N0期肿瘤中已证实存在MI，这表明这些改变可能在疾病进程早期就已发生。发现MI与吸烟史之间存在负相关（P = 0.02）。在4名非吸烟患者中有3名发现两个或更多MI标记，而在吸烟患者组的13名患者中只有1名发现，这提示非吸烟者存在一种新的致癌机制。
