Expression of cell adhesion molecules E-, P-, N-cadherin-6, -11, and -13 in renal cell carcinomas. An immunohistochemical study

研究了6种钙粘蛋白分子E-、P-、n-钙粘蛋白、钙粘蛋白-6、-11和-13在肾细胞癌（RCC）中的表达，以阐明这些分子是否参与了肾细胞癌的进展。7株RCC细胞系的Northern blot分析显示，N-cadherin和cadhelin-6分别在所有细胞系和5株细胞系中强表达，而E和P-cadherin则完全不表达。在SCID小鼠移植的KU2细胞中，N-cadherin和cadhelin-6在皮下肿瘤中检测到微量，在转移瘤中检测不到。采用冷冻切片免疫染色法检测30例手术切除的RCC中钙粘蛋白的表达。表达E-cadherin的肿瘤数量明显少于表达N-cadherin和cadhelin-6的肿瘤数量（p<0.005）。高级别肿瘤往往既不表达E-cadherin，也不表达cadhelin-6。在5例肺转移瘤中，均表达cadhelin-6, 4例表达N-cadherin， 1例表达E-cadherin。采用石蜡包埋手术切除的RCC标本，免疫组织化学方法检测E-和N-cadherin的表达，并分析病理肿瘤扩展（pT分型）与cadherin表达的相关性。每种钙粘蛋白的表达模式与上述冷冻标本几乎相同。在10例有转移灶的原发肿瘤中，分别有8例和4例检测到N-和E-cadherin， 3例观察到E-和N-cadherin的共表达。高pT肿瘤倾向于N-cadherin表达。这些结果表明，N-cadherin或cadhelin-6的表达以及E-cadhelin表达的缺失可能与RCC的进展有关，尽管还需要进一步的研究。一个结论

Expression of six cadherin molecules, E-, P-, N-cadherin, cadhelin-6,-11, and -13, in renal cell carcinomas (RCC), was investigated in order to elucidate whether these molecules are involved in the progression. Northern blot analysis of seven RCC cell lines showed that N-cadherin and cadhelin-6 were strongly expressed in all and 5 lines, respectively, whereas E, and P-cadherin were not detected at all. In KU2 cells transplanted to SCID mice, N-cadherin and cadhelin-6 were detected faintly in the subcutaneous tumors, but not in the metastatic tumors. Each cadherin expression in 30 surgically resected RCC was examined by immunostaining using frozen sections. The number of tumors expressing E-cadherin was significantly smaller than that of N-cadherin or cadhelin-6 (p<0.005). High grade tumors tended to have neither E-cadherin nor cadhelin-6 expression. In five metastatic tumors to the lung, cadhelin-6 was expressed in all, N-cadherin in 4, but E-cadherin in one. Using paraffin-embedded specimens of surgically resected RCC, expression of E- and N-cadherin was also examined immunohistochemically, and correlation between pathological tumor extension (pT classification) and the cadherin expression was analyzed. The patterns of each cadherin expression were almost the same as those in the aforementioned frozen specimens. In 10 primary tumors having metastatic lesions, N- and E-cadherin were detected in 8 and 4, respectively, and coexpression of E- and N-cadherin was observed in 3 tumors. High pT tumors tended to have N-cadherin expression. These results suggested that expression of N-cadherin or cadhelin-6, and absence of E-cadhelin expression might be correlated to the progression of RCC, although further studies will be necessary to draw. A conclusion