肿瘤抑制基因p53及p16与胃癌生物学行为的关系

Correlation between alteration of tumor suppressor gene p53, p16 and biological behavior of gastric cancer

目的探讨肿瘤抑制基因ｐ５３和ｐ１６异常与胃癌生物学行为的关系．方法采用免疫组化ＡＢＣ法检测５８例原发性胃癌（男３８例，女２０例，年龄３７岁～７６岁），Ｐ５３和Ｐ１６蛋白的表达变化．所有组织均新鲜取材，并迅速用８５０ｍｌ／Ｌ酒精固定，石蜡包埋，连续切片．结果受检组织中ｐ５３和ｐ１６阳性表达率分别为５１７％（３０／５８）和４８３％（２８／５８）．Ｐ５３蛋白在低分化胃癌（７００％）、进展期胃癌（５６９％）、淋巴结阳性胃癌（７４１％）中的表达率高于相应的高分化、早期、淋巴结阴性胃癌的表达率（２７３％，１４３％，３２３％）（Ｐ＜００５），且ｐ５３高表达多见于弥散型胃癌（同肠型胃癌比）、累及浆膜的胃癌也较局限于粘膜层的胃癌有更高的Ｐ５３蛋白表达（Ｐ＜００５）；Ｐ１６蛋白表达与胃癌大多数生物学行为无明显关系，但其在淋巴结阳性胃癌中的表达率（３３３％），低于淋巴结阴性胃癌中的表达率（６１３％）；相关性分析显示；ｐ５３阳性组织大多伴有Ｐ１６蛋白阳性表达（Ｐ＜００５）．结论Ｐ５３蛋白异常表达对胃癌生物学行为有广泛影响，Ｐ１６蛋白表达缺失可能是胃癌淋巴结转移的重要促发因素．

IM To study the correlation between abnormality of tumor suppressor gene p53, p16 and biological behavior of gastric cancer. METHODS P53 and P16 protein expressions of 58 cases of primary gastric cancer (38 males, 20 females, aged from 37 to 76 years) were detected by the immunohistochemical methods (ABC). All samples were freshly obtained and immediately fixed with 850g/L ethanol, embedded with paraffin and setioned serially. RESULTS The positive expression rate of P53 and P16 protein was 517% (30/58) and 483%(28/58), respectively. Positive expression rates of P53 protein in the poorly differentiated gastric cancer (704%), advanced gastric cancer (569%) and lymphnode involved cancer (741%) were higher than those of the highly differentiated, early and lymph node uninvolved ones(273%,143% and 323%) (P<005), and high expression of p53 protein was more frequently observed in the diffuse type (in comparison with the intestinal type) and serosal invasion ones (in comparison with mucosa located ones) (P<005). Expression of P16 protein was not relevant to most of biological behavior of gastric cancer, but there was a significant difference in p16 expression between lymph node involved ones (333%) and lymph node uninvolved ones (613%) (P<005). Relationship analysis indicated that most of p53 positive tissues were accompanied by P16 protein expression (P<005). CONCLUSION P53 protein abnormality exerts a extensive effect on biological behavior of gastric cancer. Deletion of P16 protein is mainly involved in lymph node metastasis.