Ong D E, Markert C, Chiu J F
Cancer Res. 1978 Dec;38(12):4422-6.
Rat colorectal mucosa was examined during the course of carcinogenesis, induced by chronic administration of 1,2-dimethylhydrazine (DMH), for the presence and amount of cellular retinol-binding protein (CRBP) and cellular retinoic acid-binding protein. These two binding proteins are implicated in the action of vitamin A in normal and neoplastic tissue. Induced adenocarcinomas were found to contain low levels of cellular retinoic acid-binding protein (10 pmol/g), similar to the levels found in adjacent mucosa of the same animal and also in colorectal mucosa from normal rats or rats chronically treated with DMH. However, the adenocarcinomas had high levels of CRBP (300 to 500 pmol/g), and these levels were dramatically higher than levels of CRBP in adjacent mucosa of the same animal (40 to 100 pmol/g), colorectal mucosa from normal rats (20 pmol/g), or colorectal mucosa from rats chronically treated with DMH (22 to 25 pmol/g). Consequently, the increase in CRBP occurred only with tumor appearance and not with the general hyperplasia of the crypts caused by DMH administration. The CRBP of the tumor was associated with endogenous retinol (77 to 100% saturation) and was similar to, if not identical with, CRBP of normal tissue, as judged by fluorescence spectra, sedimentation behavior, and elution position on Sephadex G-75.
在通过长期给予1,2 - 二甲基肼（DMH）诱导大鼠发生癌变的过程中，检测大鼠结肠直肠黏膜中细胞视黄醇结合蛋白（CRBP）和细胞视黄酸结合蛋白的存在情况及含量。这两种结合蛋白与维生素A在正常组织和肿瘤组织中的作用有关。研究发现，诱导产生的腺癌中细胞视黄酸结合蛋白水平较低（10 pmol/g），这与同一动物相邻黏膜以及正常大鼠或长期接受DMH处理的大鼠的结肠直肠黏膜中的水平相似。然而，腺癌中的CRBP水平较高（300至500 pmol/g），且这些水平显著高于同一动物相邻黏膜（40至100 pmol/g）、正常大鼠结肠直肠黏膜（20 pmol/g）或长期接受DMH处理的大鼠结肠直肠黏膜（22至25 pmol/g）中的CRBP水平。因此，CRBP的增加仅在肿瘤出现时发生，而不是在因给予DMH导致的隐窝普遍增生时发生。通过荧光光谱、沉降行为以及在Sephadex G - 75上的洗脱位置判断，肿瘤的CRBP与内源性视黄醇相关（饱和度为77%至100%），即便不完全相同，也与正常组织的CRBP相似。
