Molecular analysis for telomerase activity and mutations in salivary gland tumors

采用聚合酶链式反应(PCR)二核苷酸(CA)n、五核苷酸(AAAAT)n重复序列分析和免疫组织化学染色方法检测多形性腺瘤(PA)和腺样囊性癌(ACC)患者的p53抑癌基因异常。用聚合酶链式反应-杂合性缺失方法检测P53基因异常比免疫组织化学方法更敏感。本研究表明，P53基因改变是PA恶变的早期事件，在PA和ACC的发生和/或发展中起关键作用(Pathol Int 48：265-272,273-280,1998)。目前，为了探讨端粒酶在涎腺肿瘤发病机制中的作用，我们采用基于聚合酶链式反应的TRAP方法对肿瘤标本进行端粒酶活性分析。

Abnormalities of the p53 tumor suppressor gene were investigated in archival samples from patients with pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) by polymerase chain reaction (PCR)-based assays for dinucleotide (CA)n and pentanucleotide (AAAAT)n repeat polymorphisms and by immunohistochemical staining for oncoprotein expression. The detection of the p53 gene abnormality by PCR-LOH method was more sensitive than that by immunostaining. This study has demonstrated that p53 genetic alteration occurs commonly as an early event in the malignant transformation of PA and plays a critical role in the cacinogenesis and/or progression of both PA and ACC (Pathol Int 48 : 265-272, 273-280, 1998).At present, to investigate the role of telomerase in pathogenesis of salivary gland tumors, we are analyzing tumor samples for telomerase enzyme activity using the PCR-based TRAP assay.