Yuan M
General Hospital, PLA, Beijing.
Zhonghua Zhong Liu Za Zhi. 1992 Jul;14(4):267-9.
Three human mucin cDNAs (Muc-1, Muc-2, Muc-3) have recently been cloned and sequenced. The major portion of each mucin consists of sequences repeated in tandem along the protein. Three mucins are distinct due to differences in tandem repeat length, lack of sequence homology and different chromosomal locations of their genes. Since altered mucin glycosylation occurs in cancer resulting in exposure of core carbohydrate, we postulated that increased exposure or other alteration of core peptide structure may occur in cancerous tissues. Antibodies against Muc-1, Muc-2, Muc-3 tandem repeats were used for immunohistochemical analysis of normal, non-malignant and cancer tissues. The results indicate that in normal tissues, only Muc-2 expressed, while in cancerous tissues all three mucin core peptides were significantly accumulated, All of the three mucin core peptides increasingly expressed in adenoma, dysplasia epithelium and active ulcerative colitis (pre-malignant lesions), but not in the hyperplastic polyps, ischemic colitis and quiescent ulcerative colitis (non-malignant diseases).
最近已克隆并测序了三种人黏蛋白cDNA（Muc-1、Muc-2、Muc-3）。每种黏蛋白的主要部分由沿蛋白质串联重复的序列组成。三种黏蛋白因串联重复长度不同、缺乏序列同源性以及其基因在染色体上的位置不同而有所区别。由于癌症中会发生黏蛋白糖基化改变，导致核心碳水化合物暴露，我们推测癌组织中可能会出现核心肽结构的暴露增加或其他改变。针对Muc-1、Muc-2、Muc-3串联重复序列的抗体用于对正常、非恶性和癌组织进行免疫组织化学分析。结果表明，在正常组织中，仅表达Muc-2，而在癌组织中，所有三种黏蛋白核心肽均显著积累。这三种黏蛋白核心肽在腺瘤、发育异常上皮和活动性溃疡性结肠炎（癌前病变）中均呈递增表达，但在增生性息肉、缺血性结肠炎和静止期溃疡性结肠炎（非恶性疾病）中不表达。
