神经介素U蛋白在人甲状腺乳头状癌中表达的意义及作用机制

The significance and mechanism of expression of neuromedin U protein in human papillary thyroid carcinoma

目的:探讨神经介素U(NMU)蛋白在人甲状腺乳头状癌组织中的表达、临床意义及对细胞增殖的影响。方法:生物信息学分析GEPIA数据库中NMU在甲状腺乳头状癌组织及正常组织中的mRNA水平,并分析其表达与患者无病生存期的关系。进一步回顾性分析了来自河南省第二人民医院2016年3月—2022年3月接受手术治疗的71例患者的临床病理资料。采用免疫组化法检测甲状腺乳头状癌组织和正常组织中NMU蛋白表达水平,分析其与患者临床病理特征的关系。培养TPC-1和KTC-1细胞,通过NMU的shRNA质粒转染下调NMU表达,通过集落形成实验及噻唑蓝(MTT)实验检测对甲状腺乳头状癌细胞增殖的影响。结果:生物信息学分析揭示在GEPIA数据库中NMU的mRNA显著高表达,并与患者无病生存期显著相关。免疫组化揭示NMU在癌组织中显著高表达,而在正常组织中则为阴性或无表达,表达水平与肿瘤分期(高级别者42例,χ^(2)=8.184,P=0.004)及多灶(33例,χ^(2)=7.469,P=0.006)显著相关,而与患者的年龄、性别、淋巴结转移无关(均P>0.05)。MTT实验(t=7.33,P=0.0052;t=8.08,P=0.0040)及集落形成实验(t=12.43,P=0.0011;t=16.46,P=0.0005)证实,NMU在甲状腺乳头状癌细胞中的下调抑制甲状腺乳头状癌细胞增殖。结论:甲状腺乳头状癌组织中NMU显著高表达,且与患者侵袭性临床病理特征及无病生存有关,NMU蛋白促进甲状腺乳头状癌细胞增殖。

Objective:To investigate the expression and clinical significance of neuromedin U(NMU)protein in human thyroid papillary carcinoma tissues,as well as the effects on cell proliferation.Methods:The mRNA levels of NMU in thyroid papillary carcinoma tissues and corresponding normal tissues in GEPIA database were analyzed by bioinformatics,and the correlation between its expression and diseasefree survival of patients was analyzed.The clinicopathologic data of 71 patients who received surgical treatment in the Second People′s Hospital of Henan Province from March 2016 to March 2022 were retrospectively analyzed.Immunohistochemistry was used to detect the expression levels of NMU protein in papillary thyroid carcinoma tissues and paracancer tissues,and the relationship between NMU protein expression and clinicopathologic features of patients was analyze.The expression of NMU was down-regulated by shRNA plasmid transfection in TPC-1 and KTC-1 cells,and the effects on the proliferation of thyroid papillary carcinoma cells were detected by colony formation assay and thiazolyl tetrazolium(MTT)assay.Results:Bioinformatics analysis revealed that NMU mRNA was significantly overexpressed in GEPIA database,and was significantly correlated with disease-free survival.Immunohistochemistry revealed significantly high expression of NMU in cancer tissues,while negative or no expression in paracancer tissues.The expression level was significantly correlated with tumor stage(42 cases with high grade,χ^(2)=8.184,P=0.004)and multiple foci(33 cases withχ^(2)=7.469,P=0.006),but not with patient age,sex,and lymph node metastasis(all P>0.05).Both MTT(t=7.33,P=0.0052;t=8.08,P=0.0040)and colony formation assays(t=12.43,P=0.0011;t=16.46,P=0.0005)confirmed that down-regulation of NMU in thyroid papillary carcinoma cells inhibited cell proliferation.Conclusion:NMU is highly expressed in thyroid papillary carcinoma tissues,which is related to clinicopathological features and disease-free survival of patients.NMU promotes proliferation of thyroid papillary carcinoma cells.