[Expression and clinical significance of circRNA cSMARCA5 in patients with acute myocardial infarction].

Objective: To investigate the expression level and clinical significance of cSMARCA5 in the patients with acute myocardial infarction (AMI). Methods: This study was a case-control study. A total of 100 patients with AMI and 100 patients without coronary heart disease who received treatment in the Department of Cardiology, Peking University Third Hospital from September to December 2021 were included in the study according to the principle of 1∶1 frequency matching. The expression levels of cSMARCA5 in the peripheral blood of AMI patients and control groups were measured by real-time quantitative polymerase chain reaction (RT-qPCR). The receiver operating characteristic (ROC) curve was used to calculate the diagnostic ability of cSMARCA5 for AMI. Spearman or Pearson correlation analysis was used to explore the correlation between cSMARCA5 and the degree of myocardial necrosis, coronary lesion severity and GRACE risk stratification score. Bioinformatics analysis was used to predict the possible mechanism of cSMARCA5 in pathological changes of AMI. Results: The age [M (Q1,Q3)] of AMI patients and control group was 63.0 (56.0, 71.5) and 63.0 (53.0, 75.5) (P=0.622), and the proportion of males was 75.0% (75 cases) and 46.0% (46 cases) (P<0.001), respectively. The expression level [M (Q1,Q3)] of cSMARCA5 was significantly lower in AMI patients compared with the control group [0.37 (0.22, 0.73) vs 1.03(0.71, 1.75), P<0.001]. ROC analysis showed that the area under the curve of cSMARCA5 in diagnosing AMI was 0.83 (95%CI: 0.77-0.89, P<0.001), with a sensitivity of 89.0% and specificity of 67.7%. cSMARCA5 was negatively correlated with creatine kinase isoenzyme MB (r=-0.203, P=0.041), troponin T (r=-0.230, P=0.023) and N-terminal brain natriuretic peptide precursor (r=-0.250, P=0.012), and positively correlated with left ventricular ejection fraction (r=0.201, P=0.042). In addition, the expression level of cSMARCA5 was negatively correlated with SYNTAX score (r=-0.196, P=0.048) and GRACE risk score (r=-0.321, P=0.001). Bioinformatic analysis suggested that cSMARCA5 might be involved in the process of AMI through regulating the gene expression of tumor necrosis factor. Conclusions: The expression of cSMARCA5 is significantly decreased in peripheral blood of AMI patients compared with control group, and its expression level is negatively correlated with the severity of myocardial infarction. cSMARCA5 is expected to be a potential biomarker of AMI.目的： 探讨环状RNA cSMARCA5在急性心肌梗死（AMI）患者外周血中的表达水平及临床意义。 方法： 本研究为病例对照研究，纳入2021年9—12月于北京大学第三医院心内科就诊的AMI患者100例，按照1∶1匹配的原则，纳入同期经临床及冠状动脉造影除外冠心病的对照组患者100例。采用实时荧光定量聚合酶链式反应（RT-qPCR）检测AMI组和对照组患者外周血中cSMARCA5的表达量。利用受试者工作特征（ROC）曲线计算cSMARCA5对AMI的诊断能力，分析cSMARCA5与炎症指标、心肌损伤标志物、冠状动脉病变评分和全球急性冠状动脉事件注册研究（GRACE）评分的相关性。通过生物信息学分析预测cSMARCA5在AMI病理改变中可能涉及的作用机制。 结果： AMI患者和对照组患者的年龄［M（Q1，Q3）］分别为63.0（56.0，71.5）和63.0（53.0，75.5）岁（P=0.622），男性占比分别为75.0%（75例）和46.0%（46例）（P<0.001）。AMI患者外周血cSMARCA5表达水平［M（Q1，Q3）］低于对照组［0.37（0.22，0.73）比1.03（0.71，1.75），P<0.001］。cSMARCA5诊断AMI的曲线下面积为0.83（95%CI：0.77~0.89），灵敏度89.0%，特异度67.7%。cSMARCA5表达量与AMI患者的肌酸激酶同工酶MB峰值（r=-0.203，P=0.041）、肌钙蛋白T峰值（r=-0.230，P=0.023）和N末端脑钠肽前体峰值（r=-0.250，P=0.012）呈负相关，与左室射血分数呈正相关（r=0.201，P=0.042）。cSMARCA5与冠状动脉病变SYNTAX评分（r=-0.196，P=0.048）和GRACE危险分层评分（r=-0.321，P=0.001）呈负相关，与Gensini评分相关性无统计学意义（P>0.05）。生物信息学分析提示，cSMARCA5可能通过调控肿瘤坏死因子基因表达而参与AMI的病理生理过程。 结论： 环状RNA cSMARCA5在AMI患者中表达低于对照组，其表达水平与心肌梗死的严重程度负相关，可能成为AMI的潜在生物标志物。.