N—myc下游调节基因1蛋白在肾细胞癌中的表达及其意义

Expression and significance of N-myc downstream regulated gene 1 in renal cell carcinoma

目的探讨N—myc下游调节基因1（NDRG1）蛋白在肾细胞癌组织中的表达及其与微血管密度（MVD）和临床病理因素之间的关系。方法应用免疫组织化学sP法检测49例肾细胞癌及相应癌旁正常肾组织NDRG1和CD34表达，采用CD34染色进行MVD计数。结果NDRG1为细胞质和（或）膜表达蛋白，在正常肾近曲小管、远曲小管表达率为100％（49／49），显著高于在。肾细胞癌组织中的阳性率[51％（25／49）]（P〈0．05）。NDRG1表达随组织学分级增高而降低（x^2=9．968，P=0．007）；有淋巴结转移组和无淋巴结转移组NDRG1表达率分别为0（0／5）和56．8％（25／44），差异有统计学意义（X^2=5．800，P=0．016）；NDRG1表达越低，临床分期越晚（X^2=6．437，P=0．011），MVD值越高（t=2．235，P=0．030）。结论NDRGI在肾细胞癌中可能为一种抑癌基因，其表达降低与肾细胞癌侵袭、转移有关，且可能通过参与调节肾细胞癌血管形成而发挥抑制肿瘤生长和转移的作用。

Objective To study the expression of N-myc downstream regulated gene 1 （NDRGI） in renal cell carcinoma and its relationship with microvessel density （MVD） and clinicopathologic parameters. Methods Immunohistochemical study for NDRG1 and CD34 was performed on paraffin sections of cases of renal cell carcinoma and adjacent non-neoplastic renal parenchymal tissue. MVD was analyzed by CD34 immunostaining. Results Immunohistochemical study showed that non-neoplastic proximal convoluted tubule, distal convoluted tubule and collecting ducts was positive for NDRG1 （membranous and cytoplasmic）. The expression rate of NDRG1 in renal cell cancer was 51%, which was significantly lower than that in normal renal tissues of 100 % （P 〈0.05）, Clinicpathologically, the result also showed a close relation between lower NDRGI expression and higher pathologic grade （X2 =9.968, P =0.007）, later clinic stage （X2= 6.437, P =0.011）, lymph node metastases （X2=5.800, P =0.016） and higher MVD of cancer （t =2.235, P =0.030） whereas no relation with other factors. Conclusion NDRG1 might play as a cancer suppressor gene in renal cell carcinoma in that it could be correlated with tumor invasion and metastasis.It might also suppress tumor growth and metastasis by regulation of tumor angiogenesis.