WTX与NME1在结直肠癌组织中的表达变化及其关系探讨

Expression and correlation between WTX and NME1 in colorectal cancer tissues

目的观察X染色体上的肾母细胞瘤基因(WTX)与转移性基因23-H1(NME1)在结直肠癌组织中的表达变化,并分析二者的关系。方法收集新鲜结直肠癌及配对的癌旁正常结直肠组织各20例,采用qRT-PCR及免疫组化法分别检测WTX和NME1 mRNA及蛋白,分析二者表达的相关性;取人结直肠癌细胞株SW480、HCT116,采用免疫共沉淀法判定二者是否存在相互结合作用。结果 WTX基因在正常结直肠组织中相对表达量为5.917±3.580,明显高于结直肠癌组织中的表达(0.785±0.238),差异均具有统计学意义(t=6.367,P=0.000)。NME1基因在正常结直肠组织中相对表达量为2.862±1.181,明显高于结直肠癌组织中的表达(0.810±0.296),差异均具有统计学意义(t=7.236,P=0.000)。WTX与NME1蛋白在结直肠癌组织中的阳性表达率分别为15%、10%,明显低于癌旁正常结直肠组织的75%、70%(χ2=14.545,P=0.000;χ2=6.696,P=0.019)。在结直肠癌组织中,WTX和NME1蛋白表达呈正相关(r=0.793,P=0.000)。在SW480、HCT116细胞中,WTX抗体不能将NME1沉淀下来,NME1抗体也不能将WTX沉淀下来。结论 WTX与NME1表达缺失与结直肠癌的发生相关,二者表达呈明显的正相关,但无相互结合作用。

Objective To observe the expression changes of WTX and NME1 in chromosome X of colorectal cancer tissues and to analyze the correlation between them. Methods The mRNA and protein expression and correlation between WTX and NME1 was analyzed in 20 cases of human colorectal cancer and matched adjacent normal colorectal tissues by qRT-PCR and immunohistochemistry,respectively. Then,the colorectal cancer cell lines SW480 and HCT116 were selected to detect whether there was interaction between WTX and NME1 by co-immunoprecipitation assay. Results The expression of WTX in normal colorectal tissues was 5. 917 ± 3. 580,which was significantly higher than that（ 0. 785 ± 0. 238）in the matched colorectal cancer with a significant difference（ t = 6. 367,P = 0. 000）. The relative expression of NME1 in normal colorectal tissues was 2. 862 ± 1. 181,which was significantly higher than that（ 0. 810 ± 0. 296） in matched colorectal cancer with a significant difference（ t = 7. 236,P = 0. 000）. The positive expression rate of WTX in colorectal cancer was 15%,which was significantly lower than that in adjacent normal colorectal tissues（ 75%,P = 0. 000）. The positive expression rate of NME1 in colorectal cancer was 10%,which was significantly lower than that in the adjacent normal colorectal tissues（ 70%,P = 0. 019）. Meanwhile,WTX was positively correlated with NME1 in colorectal cancer（ r = 0. 793,P = 0. 000）. However,co-immunoprecipitation assay showed WTX did not directly interacted with NME1. Conclusion WTX and NME1 depletion is related to the occurrence of colorectal cancer,and they present positive correlation but do not have interacted binding effect.