食管癌前病变的肿瘤抑制基因蛋白P_(53)的免疫组化研究

研究目的目前对食管癌前病变的形态学研究很广泛,但对其分子生物学基础尚不清楚。P_(53)作为肿瘤抑制基因已被接受和重视。本文旨在进一步探讨食管癌前病变肿瘤抑制基因P_(53)的表达状况对食管癌发病学的意义。处理方法将食管癌手术切除标本经酒精固定,常规石腊包埋、切片。H-E染色作组织病理学诊断;另一连续切片作免疫组化染色。第一抗体分别采用兔多克隆血清免疫球蛋白CM-1和小鼠举克隆抗体PAb1801。结果研究的10例食管癌切除标本中,免疫组化结果显示除正常食管上皮外,基底细胞过度增生、间变和原位癌组织均表现不同程度的P_(53)免疫阳性反应。P免疫阳性细胞的数量及其在上皮内的分布与细胞的增生状态密切相关。结论在食管癌变的早期即有明显的肿瘤抑制基因蛋白P_(53)的表达。提示可能在食管病变早期阶段已发生P_(53)基因突变。

Immunohistochemical study on expression of tumor suppressor gene P_53 protein in the precancerous lesions of human esophagus

Objective To search the molecular biological basis and the significancy for the P53 protein expression in the nomal basal cell hyperplasia ( BCH) , dysplasia, carcinoma in situ and carcinoma tissue specimens of human esphagus.Interventions The specimens were surgically removed from the patients with esophageal cancer from Linxian County, China, a high risk area for esophageal cancer. The samples were fixed with alcohol and embedded in paraffin, sectioned serially at 5μm. Conventional perpoxidase method (ABC) was used. The sections were incubated overnight with two P53 antibodies, polyclonal rabbit antiserum CM 1 and murine monoclonal antibody, PAb 1801.Results Elevated P53 expression was found in precancerous and cancerous lesions of all the 10 subjects investigated. The P53 expression was not found in the normal epithelium of the esophagus. Histologically, from basal cell hyperplasia to dysplasia to carcinoma in situ, the P53 immunostain positive cells imcreased in number remarkably and appeared at a high leavel in the epithelium.Conclusion protein P53 tumor suppresor gene expression occure early in the pathogenesis of esophageal cancer.