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

本研究检测了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RCC的进展。北方印迹分析显示，N-钙粘蛋白和钙粘蛋白-6分别在所有和5个细胞系中强表达，而E，和P-钙粘蛋白在所有检测。在移植到SCID小鼠的KU 2细胞中，在皮下肿瘤中微弱地检测到N-cadherin和cadhelin-6，但在转移性肿瘤中未检测到。用免疫组化法检测30例手术切除的肾细胞癌中每种钙粘蛋白的表达。表达E-cadherin的肿瘤数量显著小于表达N-cadherin或cadhelin-6的肿瘤数量（p<0.005）。高级别肿瘤倾向于既没有E-钙粘蛋白也没有钙粘蛋白-6表达。在5例肺转移瘤中，cadhelin-6全部表达，N-cadherin表达4例，E-cadherin表达1例。使用手术切除的RCC的石蜡包埋标本，E-和N-cadherin的表达也进行了免疫组化检测，并分析病理肿瘤扩展（pT分类）和cadherin表达之间的相关性。各钙粘蛋白的表达模式与上述冷冻标本几乎相同。在10例原发肿瘤转移灶中，分别有8例和4例检测到N-和E-钙粘蛋白，3例肿瘤中观察到E-和N-钙粘蛋白的共表达。高pT肿瘤倾向于有N-钙粘蛋白表达。这些结果提示，N-cadherin或cadhelin-6的表达和E-cadhelin的表达缺失可能与肾细胞癌的进展有关，但仍需进一步研究。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