Li H, Guo L, Li J W, Liu N, Qi R, Liu J
Division of Molecular Biology, Shenyang Medical College, 110031 Shenyang, P.R. China.
Int J Oncol. 2000 Nov;17(5):927-32.
Interactions of hyaluronic acid (HA) with its binding proteins CD44 and RHAMM (receptor for HA-mediating motility) have been proposed to be important in promoting tumor progression and dissemination. However, a comparative study of their expression patterns in stomach cancer and its associated lesions is not yet available. To address this issue, the combined examinations of pathology, immunocytochemistry and Western blot hybridization were performed on advanced gastric cancer specimens as well as their preneoplastic and non-cancerous counterparts. Alternative CD44 expression was observed in the gastric mucosa with different lesions. CD44 proteins harboring variant exon 6 (CD44 v6) was detected only in cancer tissues with a total positive rate of 14% (10/74). Intracellular RHAMM molecules in Mr 93000 to 95000 were expressed in 3/31 non-cancerous mucosa. RHAMM detection rates increased along with tumor progression. Irrespective of the differences of gross and morphological pattern, majority (54/74) of cancer cases expressed multiple RHAMM isoforms in Mr 40000-45000, 64000, 70000-73000, 85000 and 93000-95000 with the appearance of cell surface immunocytochemical labeling. Among CD44 variant isoforms, v6 is more relevant with malignant transformation of gastric epithelium. Expression of RHAMM, especially the cell surface variants, is closely correlated with tumor progression (P<0.01). Expression of CD44 and RHAMM may benefit the invasion and metastasis of gastric cancer cells presumably in a reciprocal manner.
透明质酸（HA）与其结合蛋白CD44和RHAMM（HA介导的运动受体）的相互作用被认为在促进肿瘤进展和扩散中起重要作用。然而，目前尚无关于它们在胃癌及其相关病变中表达模式的比较研究。为了解决这个问题，我们对进展期胃癌标本及其癌前病变和非癌对应物进行了病理学、免疫细胞化学和蛋白质印迹杂交的联合检测。在不同病变的胃黏膜中观察到CD44的可变表达。仅在癌组织中检测到含有可变外显子6的CD44蛋白（CD44 v6），总阳性率为14%（10/74）。在31例非癌黏膜中有3例表达93000至95000 Mr的细胞内RHAMM分子。RHAMM的检测率随肿瘤进展而增加。无论大体和形态模式如何差异，大多数（54/74）癌症病例在40000 - 45000 Mr、64000 Mr、70000 - 73000 Mr、85000 Mr和93000 - 95000 Mr表达多种RHAMM异构体，并出现细胞表面免疫细胞化学标记。在CD44可变异构体中，v6与胃上皮的恶性转化更相关。RHAMM的表达，尤其是细胞表面变体，与肿瘤进展密切相关（P<0.01）。CD44和RHAMM的表达可能以相互作用的方式促进胃癌细胞的侵袭和转移。
