A review on circular RNAs in helminth parasites: Insights and potential applications

Circular RNAs (circRNAs), a coveted class of endogenous non-coding RNAs characterized by their closed-loop structure, have been extensively studied over the past decade. Research across diverse model organisms and clinical samples has established their key regulatory roles in physiological and pathological processes, including inflammation, cancer, and cardiovascular diseases. However, their functional significance and potential applications in helminth parasites remain largely unexplored. This review provides a comprehensive overview of current knowledge on circRNAs in helminth parasites, with a focus on their identification, characterization, and implications for parasite biology and host-parasite interactions. We delve into the biogenesis, structural features, stability, and functional mechanisms of circRNAs in gene regulation and cellular processes. Furthermore, we highlight their tissue-specific and developmental stage-specific expression patterns across different helminth species and conduct comparative analyses of their profiles. The review also explores the potential involvement of circRNAs in key aspects of helminth biology, such as gene regulation, host immune modulation, environmental adaptation, development, and reproduction. We address the prevailing challenges in helminth circRNA research, including technical limitations in isolation and detection, bioinformatics hurdles in accurate prediction and annotation, and the constraints of existing experimental models. Finally, we outline future prospects and potential applications, such as harnessing circRNAs as diagnostic biomarkers for infections, developing them as targets for antiparasitic interventions, and leveraging them as tools to advance our understanding of helminth biology.