MYOSITIS AND MYOPATHIES: Edited by Andrea Doria, Anna Ghirardello, and Mariele GattoThe role of cancer-associated autoantibodies as biomarkers in paraneoplastic myositis syndromeLu, Xin; Peng, Qinglin; Wang, Guochun Author Information Department of Rheumatology, China-Japan Friendship Hospital, Beijing, China Correspondence to Guochun Wang, MD, PhD, Department of Rheumatology, China-Japan Friendship Hospital, Yinhua Street, Chaoyang District, Beijing 100029, China. Tel: +86 10 84205427; e-mail: [email protected] Current Opinion in Rheumatology: November 2019 - Volume 31 - Issue 6 - p 643-649 doi: 10.1097/BOR.0000000000000641 Buy Metrics Abstract Purpose of review The aim of this study is to provide a comprehensive overview of the current insight about the clinical utility of cancer-associated autoantibodies (CAAs) as biomarkers in paraneoplastic myositis syndrome (PMS). In addition, the possible mechanisms of the relationship between malignancy and myositis onset are discussed. Recent findings It has become increasingly clear that a subgroup of the myositis-specific autoantibodies could be considered as CAAs because they are closely related to the PMS. Increased risk of cancer was found in patients with antitranscriptional intermediary factor 1-γ (TIF1-γ), antinuclear matrix protein-2 (NXP-2), anti3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) or antismall ubiquitin-like modifier 1-activating enzyme (SAE) antibodies. However, the diagnosing sensitivity and specificity of these CAAs for PMS are different among different cohort studies. Abnormally expressed or mutated autoantigen genes in tumor could possibly induce cross immunity against self-proteins and subsequently lead to the development of PMS. Summary Anti-TIF1-γ, anti-NXP-2, anti-HMGCR and anti-SAE antibodies may act as CAAs in PMS. It is necessary to closely screen and monitor for cancer in patients with CAAs. The recent studies of the relationship between CAAs and PMS provided important new insights into the disease mechanisms. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.