组织微阵列技术研究肿瘤转移相关基因在鼻咽癌中的表达与临床意义

Investigation of Clinical Significance and Expression of Tumor Metastasis-related Genes in The Nasopharyngeal Cancer Using Tissue Microarray Technique

利用高通量组织微阵列结合免疫组化检测MT1-MMP、MT2-MMP、Ezrin、nm23-H1、E-cad和TIMP-2在鼻咽癌组织中的蛋白质表达,探讨肿瘤转移相关基因异常表达在鼻咽癌侵袭转移中的作用,筛选鼻咽癌转移相关分子标志物.结果发现,鼻咽癌组织存在MT1-MMP、Ezrin蛋白高表达(P<0.01)和nm23-H1、TIMP-2蛋白低表达(P<0.05).临床Ⅱ期、Ⅲ期和Ⅳ期鼻咽癌和淋巴结转移鼻咽癌中MT1-MMP、MT2-MMP和Ezrin蛋白阳性表达显著高于临床Ⅰ期鼻咽癌和无转移癌(P<0.05,P<0.01),但临床Ⅱ期、Ⅲ期和Ⅳ期鼻咽癌和淋巴结转移鼻咽癌中nm23-H1蛋白的阳性表达显著低于临床Ⅰ期鼻咽癌和无转移癌(P<0.05).鼻咽癌组织中MT1-MMP与MT2-MMP(r=0.308,P<0.001),nm23-H1与E-cad(r=0.167,P<0.05)及TIMP-2(r=0.279,P=0.001),E-cad与TIMP-2(r=0.279,P=0.001)的蛋白质表达呈显著正相关.MT1-MMP与E-cad(r=-0.188,P<0.05)及TIMP-2(r=-0.233,P<0.05),Ezrin与E-cad(r=-0.204,P<0.05)的蛋白质表达呈显著性负相关.聚类分析显示,鼻咽癌MT1-MMP、MT2-MMP和Ezrin蛋白共同阳性表达显著高于慢性炎性鼻咽上皮(P<0.05),但nm23-H1、E-cad和TIMP-2蛋白在鼻咽癌组织中的共同阴性显著高于癌旁上皮和慢性炎性鼻咽上皮(P<0.05,P<0.01).多因素分析和有效性评估发现,MT1-MMP蛋白能较好地独立预测鼻咽癌淋巴结转移和临床进展.上述研究结果提示,多个肿瘤转移基因的蛋白质高表达,转移抑制基因的低表达和这些基因的蛋白质表达失平衡在鼻咽癌淋巴结转移和临床进展过程中起重要作用.MT1-MMP蛋白可作为预测鼻咽癌淋巴结转移的较好分子标志.

To investigate the role of abnormal protein expression of the tumor metastasis related-genes in invasion and metastasis of nasopharyngeal cancer （NPC） and to seek the metastasis-related markers for NPC, high-throughput tissue microarray and immunohistochemistry were used to detect protein expression of membrane type 1-matrix metalloproteinase （MT1-MMP）, membrane type 2-matrix metalloproteinase （MT2-MMP）, membrane-cytoskeletal crosslinker Ezrin （Ezrin）, metastasis suppressor gene nm23-H1, the epithelial cell adhesion molecule E-cadherin （E-cad）and tissue inhibitor of metalloproteinase-2 （TIMP-2） in NPC. Results showed that significant high expression of MT1-MMP and Ezrin proteins and very low expression of nm23-H1 and TIMP-2 proteins were found in NPC compared with non-cancerous nasopharyngeal epithelium （P 〈 0.05, P 〈 0.01, respectively）. Expression of MT1-MMP, MT2-MMP and Ezrin proteins in the stageⅡ, stageⅢ and Ⅳ NPC and NPC with lymph node metastasis is significantly higher than that of in the stageⅠ NPC and NPC without lymph node metastasis （P 〈 0.05, P 〈 0.01 respectively）, but expression of nm23-H1 protein in the stageⅡ, stageⅢ and Ⅳ NPC and NPC with lymph node metastasis is significantly lower than that of in the stageⅠ NPC and NPC without lymph node metastasis （P 〈 0.05）. There were significantly positive correlation between MT1-MMP and MT2-MMP （r = 0.308, P 〈 0.001）, nm23-H1 and E-cad（r = 0.167, P 〈 0.05）, nm23-H1 and TIMP-2（r = 0.279, P = 0.001）; E-cad and TIMP-2（r = 0.279, P = 0.001） in the NPC. Also, there were obviously negative correlation between MT1-MMP and E-cad（r = -0.188, P 〈 0.05）, MT1-MM and TIMP-2（r = -0.233, P 〈 0.05）, Ezrin and E-cad （r = -0.204, P 〈 0.05） in NPC. Based on the cluster analysis, there was common higher expression of MT1-MMP, MT2-MMP and Ezrin proteins in the NPC than that of in the chronic inflammatory nasopharyngeal epithelium （P 〈 0.05）. However, common higher loss expression of nm23-H1, E-cad and TIMP-2 proteins were found in NPC compared with the peri-cancer nasopharyngeal epithelium and chronic inflammatory nasopharyngeal epithelium （P 〈 0.05, P 〈 0.01）. Logistic regression analysis and validity estimation indicated that MT1-MMP gene might be better independent prognostic value for metastasis and clinical progress of NPC. The results suggested that high protein expression of multiple metastasis related-genes, low expression of the metastasis suppressor genes and loss balance between metastasis genes and metastasis suppressor genes might play important role in the metastasis and clinical progression of NPC. MT1-MMP protein can be used as the better independent prognostic molecular marker for metastasis of NPC.