Li Liubing, Liu Chenxi, Wang Qian, Wu Chanyuan, Zhang Yanfang, Cheng Linlin, Wen Xiaoting, Zeng Xiaofeng, Zhang Fengchun, Li Yongzhe
Department of Clinical Laboratory, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Key Laboratory of Rheumatology and Clinical Immunology, Ministry of Education, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
J Clin Lab Anal. 2020 Aug;34(8):e23307. doi: 10.1002/jcla.23307. Epub 2020 Mar 27.
Cancer-associated myositis (CAM) has poor prognosis and causes higher mortality. In general, myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs) have been shown to be useful biomarkers for its diagnosis.
In the present study, focus was given in assessing the presence, prevalence, and diagnostic values of myositis autoantibodies in Chinese patients diagnosed with CAM. The sera collected from 49 CAM patients, 108 dermatomyositis/polymyositis (DM/PM) patients without cancer, 105 disease controls, and 60 healthy controls were detected for the presence of 16 autoantigens (Jo-1, OJ, EJ, PL-7, PL-12, MDA5, TIF1γ, Mi-2α, Mi-2β, SAE1, NXP2, SRP, Ku, PM-Scl75, PM-Scl100, and Ro-52) using a commercial Euroline assay.
The frequency of anti-TIF1γ was significantly higher in CAM patients than in DM/PM patients without cancer (46.9% vs 14.8%, P < .001). Importantly, the sensitivity and specificity for this MSA were 46.9% and 85.2%, respectively. These helped to differentiate CAM patients from DM/PM patients without cancer. However, there was no difference in other MSAs and MAAs between CAM and DM/PM patients without cancer.
The present study indicates that anti-TIF1γ levels can serve as important biomarkers for CAM diagnosis and help in distinguishing between CAM and DM/PM patients without cancer.
癌症相关性肌炎（CAM）预后较差，死亡率较高。一般来说，肌炎特异性自身抗体（MSA）和肌炎相关性自身抗体（MAA）已被证明是其诊断的有用生物标志物。
在本研究中，重点评估了在中国诊断为CAM的患者中肌炎自身抗体的存在、患病率和诊断价值。使用商业化的Euroline检测法，检测了从49例CAM患者、108例无癌症的皮肌炎/多发性肌炎（DM/PM）患者、105例疾病对照和60例健康对照中收集的血清中16种自身抗原（Jo-1、OJ、EJ、PL-7、PL-12、MDA5、TIF1γ、Mi-2α、Mi-2β、SAE1、NXP2、SRP、Ku、PM-Scl75、PM-Scl100和Ro-52）的存在情况。
CAM患者中抗TIF1γ的频率显著高于无癌症的DM/PM患者（46.9%对14.8%，P <.001）。重要的是，这种MSA的敏感性和特异性分别为46.9%和85.2%。这些有助于将CAM患者与无癌症的DM/PM患者区分开来。然而，CAM患者与无癌症的DM/PM患者在其他MSA和MAA方面没有差异。
本研究表明，抗TIF1γ水平可作为CAM诊断的重要生物标志物，并有助于区分CAM患者与无癌症的DM/PM患者。
