膀胱癌组织和血清miR-200b甲基化状态与EMT及临床病理特征的相关性研究

The correlations of the methylation of tissue and serum miR-200b in bladder cancer patients with EMT and clinical pathological features

目的:研究膀胱癌(BLCA)组织和血清miR-200b甲基化状态与上皮间充质转化(EMT)及临床病理特征之间的关系。方法:收集了2018年9月至2020年10月在我院泌尿外科接受手术的126例BLCA患者(BLCA组)肿瘤组织标本和术前血液样本,另同期选择63例经病理证实为正常膀胱黏膜组织作为对照组。采用甲基化特异性PCR法检测组织和血清miR-200b甲基化情况,另外采用实时荧光定量PCR法检测血清miR-200b表达水平。基于癌症基因图谱(TCGA)数据库分析BLCA患者组织miR-200b表达水平与EMT相关转录因子的关系。结果:BLCA组患者组织和血清中miR-200b甲基化率明显高于对照组(P<0.05),且血清miR-200b表达水平低于对照组(P<0.05)。对于BLCA患者,肿瘤组织样本和血清样本中miR-200b甲基化检测结果一致性良好(Kappa=0.715,P<0.001),且血清miR-200b甲基化亚组血清中miR-200b表达水平显著低于未甲基化亚组(P<0.05);另外肌层浸润者、发生远处转移者或中低级别者组织和血清miR-200b甲基化率更高,同时发生淋巴结转移者血清miR-200b甲基化率也更高(P<0.05)。基于TCGA数据库,BLCA患者miR-200b表达水平与透明质酸合酶2、锌指e-box结合转录因子(ZEB)1和ZEB2蛋白的表达水平呈负相关性(P<0.05)。结论:BLCA患者组织和血清样本中普遍存在miR-200b甲基化状态,且与肌层浸润、远处转移、中低分化程度等有关,其作用机制可能是通过上调EMT相关转录因子的表达进而激活EMT过程。

Objective:To investigate the correlations of the methylation statuses of miR-200b in tissue and serum of bladder cancer(BLCA)patients with epithelial-mesenchymal transition(EMT)and clinical pathological features.Methods:From September 2018 to October 2020,the tumor tissue samples and blood samples of 126 BLCA patients who underwent surgery(BLCA group)in our hospital were collected.And 63 samples of normal bladder mucosa tissues were selected as the control group.The methylation statuses of miR-200b in tissue and serum samples were detected by methylation-specific PCR.Quantitative real-time fluorescent PCR was used to detect the expressions of serum miR-200b.Based on The Cancer Genome Atlas(TCGA)database,the relationship between miR-200b in tissues of BLCA patients and EMT related transcription factors was analyzed.Results:The methylation rate of miR-200b in BLCA group was higher than that in the control group(P<0.05),and the expression of miR-200b was lower than that in the control group(P<0.05).For BLCA patients,the results of miR-200b methylation statuses in tumor tissue and serum samples were consistent(Kappa=0.715,P<0.001),and the expression level of serum miR-200b in serum miR-200b methylation subgroup was significantly lower than that in unmethylation subgroup(P<0.05).The patients with muscle-invasive,distant metastasis or middle-low grade bladder cancer had higher methylation rates of tissue and serum miR-200b,and the patients with lymph node metastasis also had higher methylation rates of serum miR-200b(P<0.05).Based on TCGA database,the expressions of miR-200b were negatively correlated with the expression of hyaluronan synthases-2,zinc finger E-box-binding homeobox(ZEB)1 and ZEB2 proteins expressions in BLCA patients(P<0.05).Conclusion:The methylation statuses of miR-200b are common in tissue and serum samples of BLCA patients,which are related to the muscle-invasion,distant metastasis and the degree of differentiation.Its mechanism may be through up-regulating the expression of EMT related transcription factors,thus activating the EMT process.