Inhibitory effects of circulating natural autoantibodies to CD47‐derived peptides on OSCC cells

• Published in: Oral diseases Vol. 29; no. 2; pp. 445 - 457
• Main Authors: Liu, Xiu, Liang, Chao, Meng, Qingyong, Qu, Yi, He, Ziyi, Dong, Rui, Qin, Lizheng, Mao, Minghui, Hu, Ying
• Format: Journal Article
• Language: English
• Published: Denmark Wiley Subscription Services, Inc 01.03.2023
• Subjects: AKT protein; Apoptosis; Autoantibodies; Carcinoma, Squamous Cell - pathology; CD47; CD47 Antigen - genetics; CD47 Antigen - metabolism; Cell Line, Tumor; Cell Movement - genetics; Cell proliferation; Cell Proliferation - genetics; Cell viability; Enzyme-linked immunosorbent assay; Head and Neck Neoplasms; Humans; Immunoglobulin G; Immunotherapy; Kinases; Metastases; Mouth Neoplasms - pathology; natural autoantibodies; Oral cancer; Oral carcinoma; Oral squamous cell carcinoma; Peptides - pharmacology; Plasma; Squamous cell carcinoma; Squamous Cell Carcinoma of Head and Neck; tumor immunity; Tumors; oral squamous cell carcinoma; tumor immunity; CD47; natural autoantibodies
• ISSN: 1354-523X; 1601-0825; 1601-0825
• DOI: 10.1111/odi.13922

Objectives Natural autoantibodies serve as an important anti‐tumorigenic component in the body. This study was thus designed to investigate whether circulating natural IgG autoantibodies against a cluster of differentiation 47 (CD47) could exert inhibitory effects on oral squamous cell carcinoma (OSCC). Subjects and methods The expression levels of 13 tumor‐targeted genes in three OSCC cell lines were analyzed by qPCR, and CD47 expression in OSCC tissues was also verified with IHC staining. An in‐house ELISA was performed to analyze circulating anti‐CD47 IgG levels in control subjects, oral benign tumor, and OSCC patients, and to detect anti‐CD47 IgG‐abundant plasma. Three OSCC cell lines were treated with anti‐CD47 IgG‐abundant and ‐deficient plasma, respectively, followed by the analysis of cell proliferation, apoptosis, and invasion/metastasis. Results The CD47 gene showed the highest expression among 13 genes detected in three OSCC cell lines; its expression was significantly higher in OSCC tissues than adjacent tissues. Plasma anti‐CD47 IgG levels showed the differences between control subjects, oral benign tumor, and OSCC patients. Anti‐CD47 IgG‐abundant plasma could evidently reduce cell viability via suppressing p‐AKT expression and inducing cell apoptosis and inhibit the invasion of all three OSCC cell lines. Conclusions Natural autoantibodies against CD47 may be a potential agent for OSCC immunotherapy.