Membrane changes during urothelial hyperplasia and neoplasia.
Membrane changes during urothelial hyperplasia and neoplasia.
复制标题
尿路上皮增生和肿瘤期间的膜变化。
作者：
R. Hicks;J. Wakefield
正常哺乳动物的尿道上皮具有复杂的形态发生和细胞分化模式。多倍体表面细胞的腔面受到具有高度有序亚结构的形态学独特的质膜的限制。这种膜是尿道上皮正常分化的一个方便的标记。在可逆的良性增生中，在细胞毒性损伤后，细胞最表层的腔面受到与正常基底细胞质膜相当的未分化膜的限制。当增生消退时，尿道上皮的正常分化得以重建，并再次产生正常的特化表面膜。在由各种致癌方案诱导的癌前增生和早期瘤形成中，在一些表面细胞中观察到影响表面膜的新的分化形式。微绒毛形成于其游离腔面，并由具有不寻常的结构化糖萼的膜限制，这在正常尿路上皮或良性增生中未发现。这种糖萼也出现在人类膀胱移行细胞癌的某些细胞上，这种新的糖萼可能是膀胱肿瘤转化的形态学标志。
Normal mammalian urothelium has a complex pattern of morphogenesis and cell differentiation. The luminal face of the polyploid, superficial cells is limited by a morphologically unique plasma membrane with a highly ordered substructure. This membrane is a convenient marker for normal differentiation in the urothelium. In reversible, benign hyperplasia, following cytotoxic damage, the luminal face of the most superficial layer of cells is limited by an undifferentiated membrane which is comparable to the plasma membrane of normal basal cells. When the hyperplasia regresses, normal differentiation of the urothelium is reestablished, and the normal, specialized surface membrane is again produced. In both preneoplastic hyperplasia and early neoplasia induced by various carcinogenic regimens, a novel form of differentiation affecting the surface membrane is seen in some superficial cells. Microvilli form on their free luminal face and are limited by a membrane with an unusual, structured glycocalyx, which is not found in normal urothelium or benign hyperplasia. This glycocalyx also develops on some cells in transitional cell carcinoma of the bladder in man. This novel glycocalyx may be a morphological marker for neoplastic transformation in the urothelium.