人食管鳞状细胞癌中微RNA-1250及其宿主基因AATK的表达及甲基化状态分析

Expressions of microRNA-1250 and its host gene AATK and AATK gene methylation status in human esophageal squamous cell carcinoma

目的:探讨微RNA-1250(microRNA-1250,miR-1250)及其宿主基因细胞凋亡关联酪氨酸激酶(apoptosis-associated tyrosine kinase,AATK)在食管鳞状细胞癌(esophageal squamous cell carcinoma,ESCC)发生和发展中的作用。方法:分别采用实时荧光定量PCR法和甲基化特异性PCR法检测AATK基因在食管癌细胞系和ESCC组织及其相应癌旁正常组织中的表达情况和甲基化状态,同时采用实时荧光定量PCR法检测miR-1250在ESCC组织及其相应癌旁正常组织中的表达情况。然后,分析miR-1250表达和AATK基因表达及其甲基化状态分别与ESCC组织病理学特征的关系,以及三者之间的相关性。结果:5-杂氮-2’-脱氧胞苷(5-aza-2’-deoxycytidine,5-Aza-dC)处理后,4株食管癌细胞系中AATK基因表达水平明显升高(P值均<0.05),并且其甲基化程度明显降低。在ESCC组织中,AATK mRNA平均表达量低于癌旁正常组织(P<0.05),AATK基因甲基化率明显高于癌旁正常组织(P<0.05);AATK mRNA相对表达量和AATK基因甲基化率均与淋巴结转移、组织分化程度及TNM分期密切相关(P值均<0.05),而与患者年龄和性别无关(P值均>0.05)。同时,ESCC组织中miR-1250相对表达量明显低于癌旁正常组织(P<0.05),并与淋巴结转移、组织分化程度及TNM分期密切相关(P值均<0.05),而与患者年龄和性别无关(P值均>0.05)。ESCC组织中miR-1250与AATK mRNA表达明显相关(P<0.05),而且miR-1250和AATK mRNA表达与AATK基因甲基化状态也均明显相关(P值均<0.05)。结论:ESCC的发生和发展可能与miR-1250和AATK低表达以及AATK基因高甲基化状态有关,而且miR-1250与AATK mRNA表达具有一致性。

Objective： To explore the role of microRNA-1250 （miR-1250） and its host gene apoptosis- associated tyrosine kinase （AATK） in occurrence and development of esophageal squamous cell carcinoma （ESCC）. Methods： The expression and methylation status of AATK gene in esophageal cancer cell lines, ESCC tissues and the corresponding noncancerous tissues were detected by real-time fluorescent quantitative PCR and methylation specific PCR, respectively. The expression of miR-1250 in ESCC tissues and the corresponding noncancerous tissues was detected by real-time fluorescent quantitative PCR. The relationship of histopathological features with miR-1250 expression, AATK gene expression and its methylation in ESCC tissues, as well as the correlation of miR-1250 expression, AATK gene expression and its methylation were analyzed. Results： After 5-aza-2＇-deoxycytidine （5-Aza-dC） treatment, the relative expressions of AATK mRNAs in four kinds of esophageal cancer cell lines were significantly increased （all P 〈 0.05）, and the methylation status of AATK gene was obviously decreased. The average expression level of AATK mRNA in ESCC tissues was significantly lower than that in the corresponding normal tissues （P 〈 0.05）. The methylation frequency of AATK gene in ESCC tissues was significantly higher than that in the corresponding normal tissues （P 〈 0.05）. The expression and methylation ofAATK gene were closely correlated with lymph node metastasis, pathological differentiation and TNM stages of ESCC tissues （all P 〈 0.05）, but which were not correlated with age and gender of ESCC patients （both P 〉 0.05）. The average expression level of miR-1250 in ESCC tissues was significantly lower than that in the corresponding normal tissues （P 〈 0.05）. The expression of miR-1250 was closely correlated with lymph node metastasis, pathological differentiation and TNM stages of ESCC tissues （all P 〈 0.05）, but which was not correlated with age and gender of ESCC patients （both P 〉 0.05）. The expression of miR-1250 was significantly correlated with the expression of AATK mRNA in ESCC tissues （P 〈 0.05）, and the expressions of miR-1250 and AATK mRNA were significantly correlated with the methylation status ofAATK gene （both P 〈 0.05）. Conclusion： The occurrence and development of ESCC may be related to the decreased expressions of miR-1250 and AATK mRNA as well as the high methylation status of AATK gene. Furthermore, the expression of miR-1250 was consistent with AATK gene expression.