微卫星位点TP53、D9S1747、D9S162及RPS6的杂合性缺失与口腔鳞状细胞癌的关系

目的 检测微卫星位点TP53(位于17p13区)、D9S1747、D9S162、RPS6(均位于9p21区)在口腔鳞状细胞癌中的杂合性缺失(1oss of heterozygosity,LOH)和微卫星不稳定(microsatellite instability,MI)与临床病理因素及预后的关系.方法 取71例符合纳入标准的口腔鳞状细胞癌病变组织,用基因组DNA快速提取纯化试剂盒提取肿瘤组织及对应正常淋巴结或外周血的DNA,聚合酶链反应(PCR)变性电泳检测上述位点的基因变化.结果 所有位点在癌组织中的LOH和MI总发生率为68%(48/71);TP53(17p13)为56%(35/63),9p21(RPS6+D9S1747+D9S162)为59%(40/68);9p21的LOH、MI与WHO组织学分级和淋巴结转移有关(P＜0.05);17p13的LOH、MI与WHO组织学分级(P＜0.01)和临床分期有关(P＜0.05);TP53(17p13)和9p21在肿瘤组织中的LOH和MI对口腔鳞状细胞癌的预后有显著影响(P＜0.05);TP53(17p13)LOH阳性组术后生存率显著低于阴性组(P＜0.01);9p21的LOH和MI阳性组术后生存率显著低于阴性组(P＜0.05).结论 所检测位点的LOH和MI与口腔鳞状细胞癌的病理分级、临床分期和淋巴结转移有关;癌组织中TP53的变化是口腔鳞状细胞癌预后较差的独立影响因素.

Abstract：

Objective To investigate the correlation between the frequency of molecular abnormalities of 4 loci at chromosomal 9p21 (D9S1747 ,D9S162, RPS6) and 17p13 (TP53) and the clinical characteristics and prognosis. Methods The oral squamous cell carcinoma(OSCC) lesions in 71 patients were manually microdessected. Genomic DNA from these lesions and normal lymphnode tissu or peripheral blood of the same patients were extracted using the Watson's tissue kit. The loss of heterozygosity(LOH) and microsatellite instability (MI) of 17p13 and 9p21 were analyzed by PCR-page electrophoresis after DNA extraction. Results LOH and MI were detected in the OSCC of 48 patients (68%). The LOH and MI frequency at chromosomes 17p13 and 9P21 were 56% (35/63) and 59% (40/68) respectively. The LOH and MI frequency at 9p21 was significantly associated with WHO grading ( P ＜ 0.01 ) and lymphonode metastasis (P ＜0.01 ). The LOH and MI frequency at 17p13 was significantly associated with clinical stage (P ＜ 0.05 ). TP53 genetic aberration and 9p21 genetic aberration were significant prognostic factors for OSCC. The prognosis was poor in the LOH and MI positive group of chromosome 17p13 and 9p21. The frequency of LOH and MI at TP53 was the only independent factor for overall survival ( P ＜ 0.05 ).Conclusions The LOH and MI of 17p13 and 9p21 were related to clinical stage and lymphonode metastasis. LOH of TP53 was an independent prognostic factor for OSCC.

Molecular analysis of TP53, D9S1747, D9S162 and RPS6 in oral squamous cell carcinoma

Objective To investigate the correlation between the frequency of molecular abnormalities of 4 loci at chromosomal 9p21 (D9S1747 ,D9S162, RPS6) and 17p13 (TP53) and the clinical characteristics and prognosis. Methods The oral squamous cell carcinoma(OSCC) lesions in 71 patients were manually microdessected. Genomic DNA from these lesions and normal lymphnode tissu or peripheral blood of the same patients were extracted using the Watson's tissue kit. The loss of heterozygosity(LOH) and microsatellite instability (MI) of 17p13 and 9p21 were analyzed by PCR-page electrophoresis after DNA extraction. Results LOH and MI were detected in the OSCC of 48 patients (68%). The LOH and MI frequency at chromosomes 17p13 and 9P21 were 56% (35/63) and 59% (40/68) respectively. The LOH and MI frequency at 9p21 was significantly associated with WHO grading ( P ＜ 0.01 ) and lymphonode metastasis (P ＜0.01 ). The LOH and MI frequency at 17p13 was significantly associated with clinical stage (P ＜ 0.05 ). TP53 genetic aberration and 9p21 genetic aberration were significant prognostic factors for OSCC. The prognosis was poor in the LOH and MI positive group of chromosome 17p13 and 9p21. The frequency of LOH and MI at TP53 was the only independent factor for overall survival ( P ＜ 0.05 ).Conclusions The LOH and MI of 17p13 and 9p21 were related to clinical stage and lymphonode metastasis. LOH of TP53 was an independent prognostic factor for OSCC.