B细胞特异性莫洛氏鼠白血病病毒插入位点-1蛋白在口腔黏膜癌变过程中的表达

Over-expression of Bmi-1 protein in oral precancerous lesions and squamous cell carcinomas

目的了解B细胞特异性莫洛氏鼠白血病病毒插入位点-1(Bmi-1)在口腔黏膜癌变过程中的表达水平变化,探讨其在口腔鳞癌发生发展中的作用及意义。方法选取正常口腔黏膜10例、上皮异常增生31例、口腔鳞癌61例的石蜡包埋组织,采用免疫组化SP法检测相应组织中Bmi-1蛋白表达情况,分析Bmi-1蛋白表达在口腔黏膜癌变过程中的作用及意义。结果Bmi-1在正常口腔黏膜无表达,在上皮异常增生及口腔鳞癌中阳性率分别为29%(9/31)和62.3%(38/61),口腔鳞癌组Bmi-1阳性率高于正常上皮组及上皮异常增生组,差异均有统计学意义(P<0.05)。Bmi-1阳性率随上皮异常增生程度增加及肿瘤分化程度降低而增加,两者间存在正相关关系(r=0.964,P<0.05),Bmi-1阳性表达与口腔鳞癌临床分期及淋巴结转移密切相关(P<0.05)。结论Bmi-1过表达是口腔黏膜癌变过程中的早期事件并与口腔鳞癌发生发展进程有关,有可能作为临床评估口腔鳞癌侵润、转移和预后的参考指标之一。

Objective To investigate the expression and the clinicopathological significance of B-cell-specific Moloney leukemia virus insertion site-1 （Bmi-1） protein in oral precancerous lesions and oral squamous cell carcinoma （OSCC）. Methods The level of Bmi-1 protein in paraffin-embeded tissue sections of 10 cases of normal oral epithelium, 31 cases of epithelium dysplasia and 61 cases of OSCC were determined by immunohistochemistry. The clinical and pathological significances of Bmi-1 over- expression in oral carcinogenesis were statistically analyzed by SPSS 11.5. Results Bmi-1 protein was not detectable in normal oral epithelium and significantly altered from mild-dysplasia to OSCC. The percentages of Bmi-1 over-expression were 29%（9/31） in dysplasia and 62.3%（38/61） in OSCC. The percentage of Bmi-1 over-expression in OSCC was significantly higher than that in normal oral epithelium and dysplasia tissues （P 〈 0.05）. Statistical analysis revealed a strong correlationship between Bmi-1 expresson and the TNM stages, as well as the lymph node metastasis in OSCC （P 〈 0.05）. Conclusions Bmi-1 up-regulation was an early event in oral carcinogenesis and was related to tumor progression. Bmi- 1 could be used as a marker for assessing the progression of OSCC and provided a basis for clinical therapeutic decisions.