Journal Article

Tumour circular RNAs elicit anti-tumour immunity by encoding cryptic peptides

Wang, Jiawen, Ye, Shuying, Saw, Phei Er, Zhang, Yin, Zhu, Xiaofeng, Yang, Bing, Xin, Min, Song, Erwei, Zhang, Jiahui, Lao, Liyan, Zeng, Xin, Nie, Yan, Chen, Jianing, Liao, Jianyou, Huang, Di, Su, Shicheng, Zhang, Ning

2024

Overview

Emerging data have shown that previously defined noncoding genomes might encode peptides that bind human leukocyte antigen (HLA) as cryptic antigens to stimulate adaptive immunity 1 , 2 . However, the significance and mechanisms of action of cryptic antigens in anti-tumour immunity remain unclear. Here mass spectrometry of the HLA class I (HLA-I) peptidome coupled with ribosome sequencing of human breast cancer samples identified HLA-I-binding cryptic antigenic peptides that were noncanonically translated by a tumour-specific circular RNA (circRNA): circFAM53B. The cryptic peptides efficiently primed naive CD4 + and CD8 + T cells in an antigen-specific manner and induced anti-tumour immunity. Clinically, the expression of circFAM53B and its encoded peptides was associated with substantial infiltration of antigen-specific CD8 + T cells and better survival in patients with breast cancer and patients with melanoma. Mechanistically, circFAM53B-encoded peptides had strong binding affinity to both HLA-I and HLA-II molecules. In vivo, administration of vaccines consisting of tumour-specific circRNA or its encoded peptides in mice bearing breast cancer tumours or melanoma induced enhanced infiltration of tumour-antigen-specific cytotoxic T cells, which led to effective tumour control. Overall, our findings reveal that noncanonical translation of circRNAs can drive efficient anti-tumour immunity, which suggests that vaccination exploiting tumour-specific circRNAs may serve as an immunotherapeutic strategy against malignant tumours. The tumour-specific circular RNA FAM53B is highly immunogenic and can induce anti-tumour responses in mouse models of breast cancer and melanoma, expanding the repertoire of anticancer targets for development.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 13 / 38 / 45 / 59 / 631/67/1347 / 631/67/580 / 82 / Animals / Antigen (tumor-associated) / Antigens / Antigens, Neoplasm - immunology / Binding / Breast cancer / Breast Neoplasms - genetics / Breast Neoplasms - immunology / Breast Neoplasms - mortality / Breast Neoplasms - pathology / CD4 antigen / CD4-Positive T-Lymphocytes - immunology / CD8 antigen / CD8-Positive T-Lymphocytes - immunology / Circular RNA / Cytotoxicity / Female / Genomes / Histocompatibility antigen HLA / Histocompatibility Antigens Class I - immunology / Histocompatibility Antigens Class II - immunology / Humanities and Social Sciences / Humans / Immunity / Immunotherapy / Infiltration / Lymphocytes / Lymphocytes T / Mass Spectrometry / Mass spectroscopy / Melanoma / Melanoma - genetics / Melanoma - immunology / Melanoma - mortality / Melanoma - pathology / Metastases / Mice / multidisciplinary / Peptides / Peptides - genetics / Peptides - immunology / Protein Biosynthesis / Proteins / Ribonucleic acid / Ribosome Profiling / RNA / RNA, Circular - genetics / RNA, Circular - metabolism / Science / Science (multidisciplinary) / Scientific imaging / Survival Analysis / Tumors / Vaccination