Michelassi F, Erroi F, Roncella M, Block G E
Department of Surgery, University of Chicago, Illinois.
Dis Colon Rectum. 1989 Aug;32(8):665-8. doi: 10.1007/BF02555770.
To gain a better understanding of the biologic development of rectal adenocarcinomas, the authors evaluated the level of ras gene protein product (p21) in the available material of 74 Dukes' B adenocarcinomas, 64 Dukes' C adenocarcinomas, and 60 lymph-node metastases resected at the University of Chicago Medical Center between 1965 and 1981. Pathologic slides and archival paraffin blocks were retrieved for confirmation of the original diagnosis and measurement of p21 content. P21 titers were obtained using the RAP-5 monoclonal antibody in a semiquantitative immunohistochemical assay. Titer was expressed as the highest dilution giving definitive staining using the avidin-biotin peroxidase method. The analysis indicated that a higher percentage of Dukes' stage C rectal adenocarcinomas had high (greater than or equal to 1:40,000) p21 titers than Dukes' B adenocarcinomas (68.8 vs. 51.4 percent, respectively, P less than 0.05). In view of recent data suggesting that ras oncogene expression confers invasive and metastatic capabilities to NIH 3T3 cells, the authors believe this study offers evidence that overexpression of ras oncogene with overproduction of p21 protein product may be an important prerequisite for the acquisition of metastatic capabilities in the early stages of colon cancer.
为了更好地了解直肠腺癌的生物学发展过程，作者对1965年至1981年间在芝加哥大学医学中心切除的74例杜克B期腺癌、64例杜克C期腺癌以及60例淋巴结转移灶的现有材料中的ras基因蛋白产物（p21）水平进行了评估。检索病理切片和存档石蜡块以确认原诊断并测量p21含量。使用RAP-5单克隆抗体通过半定量免疫组织化学测定法获得p21滴度。滴度表示为使用抗生物素蛋白-生物素过氧化物酶方法进行明确染色的最高稀释度。分析表明，与杜克B期腺癌相比，杜克C期直肠腺癌中具有高（大于或等于1:40,000）p21滴度的比例更高（分别为68.8%和51.4%，P<0.05）。鉴于最近的数据表明ras癌基因表达赋予NIH 3T3细胞侵袭和转移能力，作者认为本研究提供了证据，表明ras癌基因的过度表达以及p21蛋白产物的过量产生可能是结肠癌早期获得转移能力的重要先决条件。
