Gates R E, Rees R S
Cancer. 1985 Dec 1;56(11):2598-604. doi: 10.1002/1097-0142(19851201)56:11<2598::aid-cncr2820561111>3.0.co;2-r.
Since vitamin A inhibits the terminal differentiation of keratinocytes, elevated levels of cytoplasmic vitamin A-binding proteins could explain the reduced tendency of squamous cell carcinomas to undergo terminal differentiation. The levels of cellular retinol-binding protein (CRBP) and cellular retinoic acid-binding protein (CRABP) were determined in 37 squamous cell carcinomas of the head and neck and were compared with the corresponding levels in adjacent normal tissue. The CRBP levels expressed per milligram of DNA were increased threefold (P = 0.0005) in the tumor as compared with normal tissue. In contrast, CRABP levels expressed per milligram were decreased 2.5-fold (P = 0.0007) in the tumor as compared with normal tissue. Despite significant differences in retinoid-binding protein levels between tumor and adjacent normal tissue, there was no significant correlation of these differences with any of the patient clinical parameters or any of the tumor growth characteristics. The increased CRBP levels may explain why terminal differentiation, an important mechanism for limiting growth in normal keratinocytes, is less readily induced in squamous cell carcinomas.
由于维生素A抑制角质形成细胞的终末分化，细胞质中维生素A结合蛋白水平升高可以解释鳞状细胞癌终末分化倾向降低的原因。测定了37例头颈部鳞状细胞癌中细胞视黄醇结合蛋白（CRBP）和细胞视黄酸结合蛋白（CRABP）的水平，并与相邻正常组织中的相应水平进行比较。与正常组织相比，肿瘤中每毫克DNA表达的CRBP水平增加了三倍（P = 0.0005）。相反，与正常组织相比，肿瘤中每毫克表达的CRABP水平降低了2.5倍（P = 0.0007）。尽管肿瘤组织与相邻正常组织之间的类视黄醇结合蛋白水平存在显著差异，但这些差异与任何患者临床参数或任何肿瘤生长特征均无显著相关性。CRBP水平升高可能解释了为什么终末分化（一种限制正常角质形成细胞生长的重要机制）在鳞状细胞癌中较难被诱导。
