结直肠癌组织中DTX2分子的表达及临床意义

Expression of DTX2 molecule in colorectal cancer tissues and its clinical significances

目的探讨DTX2分子在结直肠癌(CRC)组织中的表达及临床意义。方法利用Oncomine、GEPIA数据库分析DTX2基因在CRC组织与正常结直肠组织(简称“正常组织”)中的表达情况,同时运用人类蛋白图谱(HPA)数据库在线数据分析DTX2蛋白表达与CRC患者生存预后的关系。采用实时荧光定量PCR法(qRT-PCR法)、Western blot法及免疫组织化学染色法检测大连大学附属新华医院的55例CRC组织及其相应的癌旁正常(PN)组织中DTX2 mRNA及蛋白表达,并分析CRC组织中DTX2表达与CRC患者临床病理特征的关系。结果(1)Oncomine和GEPIA数据库中的数据均发现,DTX2 mRNA在CRC组织中的表达水平均明显高于正常组织(P<0.05);HPA在线数据分析结果发现,DTX2低表达CRC患者的总生存情况好于DTX2高表达者(P=0.0098)。(2)qRT-PCR法和Western blot法检测结果均显示CRC组织中DTX2 mRNA和蛋白表达水平均明显高于PN组织(t=0.722,P<0.001;t=1.314,P<0.001);免疫组织化学染色结果显示,CRC组织中DTX2蛋白表达阳性率高于PN组织(χ^(2)=0.899,P<0.001),而且DTX2蛋白表达阳性率、mRNA和蛋白表达量均与CRC患者的肿瘤浸润深度、淋巴结转移及TNM分期有关,即肿瘤浸润深度越深、淋巴结分期和TNM分期越晚者,DTX2蛋白表达阳性率、mRNA和蛋白表达量越高(P<0.05)。结论DTX2基因在CRC组织中的高表达提示其可能作为评估CRC进展的新生物学指标,但DTX2蛋白表达对CRC预后的评估价值需临床进一步验证。

Objective To detect expression of DTX2 molecule in colorectal cancer(CRC)tissues and investigate its clinical significances.Methods Oncomine and GEPIA databases were used to analyze the expression of DTX2 gene in CRC tissues and normal colorectal tissues,and online data of human protein atlas(HPA)was used to analyze the relationship between DTX2 protein expression and survival prognosis of patients with CRC.The expressions of DTX2 mRNA and protein were detected in the 55 cases of CRC tissues and corresponding paracancerous normal(PN)tissues by using qRT-PCR,Western blot,and immunohistochemistry methods,respectively.The correlations between the expression of DTX2 and the clinicopathologic characteristics were analyzed.Results(1)The data from Oncomine and GEPIA databases showed that the expression levels of DTX2 mRNA in the CRC tissues were significantly higher than those in the normal colorectal tissues(P<0.05);HPA online data analysis showed that the overall survival of CRC patients with low expression of DTX2 was better than that with high expression of DTX2(P=0.0098).(2)The results of qRT-PCR and Western blot showed that the expression levels of DTX2 mRNA and protein in the CRC tissues were higher than those in the PN tissues(t=0.722,P<0.001;t=1.314,P<0.001);The results of immunohistochemical staining showed that the positive rate of DTX2 protein expression in the CRC tissues was higher than that in the PN tissues(χ^(2)=0.899,P<0.001).The positive rate of DTX2 protein expression and the expression levels of DTX2 mRNA and protein were related to the depth of tumor invasion,lymph node metastasis,and TNM stage of CRC patients,that was,the deeper depth of tumor invasion,the more lymph node metastasis,and the later TNM stage,the higher positive rate of DTX2 protein expression,the higher expression levels of DTX2 mRNA and protein(P<0.05).Conclusions DTX2 protein may be a novel biomarker for estimating progression of CRC.However,prognosis evaluation of DTX2 protein on CRC needs further clinical research.