Circular RNAs: A Potential Regulator in Environmental Chemical Carcinogenesis

Circular RNA (circRNA), a class of evolutionarily conserved, structurally stable, and tissue-specifically expressed noncoding RNA, is increasingly recognized as a key regulator of diverse biological processes and disease pathogenesis, including cancer. While the roles of circRNAs in tumorigenesis are well-documented, their involvement in the tumorigenesis induced by environmental chemical carcinogens (ECCs) remains relatively unexplored. Recent studies have identified aberrant expressions of specific circRNAs during ECC exposure-related carcinogenesis, suggesting their critical regulatory functions. Given their unique structure and broad regulatory roles, circRNAs exhibit great potential as diagnostic, therapeutic, and prognostic biomarkers for ECC exposure-associated cancers. This review summarizes the characteristics and functions of circRNAs, as well as the potential regulatory mechanisms in ECC exposure-induced cancer and the dysregulations of circRNAs caused by ECCs. We highlight the complexity and heterogeneity of circRNA regulatory networks, emphasizing the need for integrated and dynamic investigations to fully elucidate the underlying mechanisms. Future research efforts should prioritize biomarker studies to facilitate the prevention, early detection, and effective treatment of ECC exposure-associated cancers.