Xie Minghong, Zhao Yunlong, Hou Xiaohua, Li Ning, Liu Haiwei, Zhang Xiaoyi, Xu Xinju
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Henan Polytechnic University (The Second People's Hospital of Jiaozuo), Jiaozuo, Henan 454000, China.
Pathology Department, The First Affiliated Hospital of Henan Polytechnic University (The Second People's Hospital of Jiaozuo), Jiaozuo, Henan 454000, China.
Clin Chim Acta. 2025 May 15;572:120273. doi: 10.1016/j.cca.2025.120273. Epub 2025 Mar 29.
Malignant pleural effusion (MPE) is a thoracic complication disease characterized by tumors, predominantly resulting from advanced lung cancer. This study aimed to investigate the efficacy of SHOX2 and RASSF1A methylation as a supplementary diagnostic tool for lung cancer-induced MPE with uncertain pathological diagnoses.
Methylation-specific polymerase chain reaction (MS-PCR) was used to assess SHOX2 and RASSF1A methylation levels in 98 pleural effusion samples. The cut-off values for SHOX2 and RASSF1A methylation levels for the detection of MPE were determined through receiver operating characteristic (ROC) curve analysis, with corresponding sensitivity and specificity analyses. The chi-square test was used to evaluate the relationship between SHOX2 and RASSF1A methylation levels and clinical characteristics or immunohistochemical markers in patients with MPE.
For the diagnosis of MPE, the area under the ROC curve (AUC) values for SHOX2 and RASSF1A methylation levels were 0.820 and 0.718, respectively, with a combined AUC value of 0.881. The sensitivity and specificity of SHOX2 methylation levels were 68.4 % and 92.7 %, respectively, whereas those of RASSF1A methylation levels were 47.4 % and 97.7 %, respectively. The combined detection of SHOX2 and RASSF1A (using the LungMe® assay kit) exhibited a sensitivity of 82.5 %, which exceeded that of cytological analysis (29.8 %). The sensitivity and specificity of combined cytological analysis and LungMe® assay were 89.5 % and 92.7 %, respectively. SHOX2 methylation levels were significantly higher in patients without EGFR mutations than in those with EGFR mutations. The methylation levels of SHOX2 and RASSF1A were higher in smokers than in non-smokers and PDL1-positive patients than in PDL1-negative patients; however, the differences were not statistically significant. The methylation levels of both genes were higher in TTF-1-positive patients than in TTF-1-negative patients, with the difference being statistically significant for RASSF1A.The methylation levels of neither SHOX2 nor RASSF1A were associated with patient survival, whereas PDL1 expression was identified as an independent risk factor for the survival of patients with MPE (hazard ratio = 4.109).
Methylation of SHOX2 and RASSF1A serves as a valuable diagnostic biomarker for MPE, providing an adjunct to cytological diagnosis.
恶性胸腔积液（MPE）是一种以肿瘤为特征的胸部并发症疾病，主要由晚期肺癌引起。本研究旨在探讨SHOX2和RASSF1A甲基化作为病理诊断不明确的肺癌所致MPE辅助诊断工具的有效性。
采用甲基化特异性聚合酶链反应（MS-PCR）检测98例胸腔积液样本中SHOX2和RASSF1A的甲基化水平。通过受试者操作特征（ROC）曲线分析确定SHOX2和RASSF1A甲基化水平检测MPE的临界值，并进行相应的敏感性和特异性分析。采用卡方检验评估MPE患者SHOX2和RASSF1A甲基化水平与临床特征或免疫组化标志物之间的关系。
对于MPE的诊断，SHOX2和RASSF1A甲基化水平的ROC曲线下面积（AUC）值分别为0.820和0.718，联合AUC值为0.881。SHOX2甲基化水平的敏感性和特异性分别为68.4%和92.7%，而RASSF1A甲基化水平的敏感性和特异性分别为47.4%和97.7%。联合检测SHOX2和RASSF1A（使用LungMe®检测试剂盒）的敏感性为82.5%，超过了细胞学分析的敏感性（29.8%）。联合细胞学分析和LungMe®检测的敏感性和特异性分别为89.5%和92.7%。无EGFR突变患者的SHOX2甲基化水平显著高于有EGFR突变患者。吸烟者的SHOX2和RASSF1A甲基化水平高于非吸烟者，PDL1阳性患者高于PDL1阴性患者；然而，差异无统计学意义。TTF-1阳性患者的两个基因甲基化水平均高于TTF-1阴性患者，RASSF1A的差异具有统计学意义。SHOX2和RASSF1A的甲基化水平均与患者生存无关，而PDL1表达被确定为MPE患者生存的独立危险因素（风险比=4.109）。
SHOX2和RASSF1A甲基化可作为MPE的有价值诊断生物标志物，为细胞学诊断提供辅助。
