Aristolochic acids (AAs) are a group of naturally occurring compounds present in many plant species of the Aristolochiaceae family. Exposure to AA is a significant risk factor for severe nephropathy, and urological and hepatobiliary cancers (among others) that are often recurrent and characterized by the prominent mutational fingerprint of AA. However, herbal medicinal products that contain AA continue to be manufactured and marketed worldwide with inadequate regulation, and possible environmental exposure routes receive little attention. As the trade of food and dietary supplements becomes increasingly globalized, we propose that further inaction on curtailing AA exposure will have far-reaching negative effects on the disease trends of AA-associated cancers. Our Review aims to systematically present the historical and current evidence for the mutagenicity and carcinogenicity of AA, and the effect of removing sources of AA exposure on cancer incidence trends. We discuss the persisting challenges of assessing the scale of AA-related carcinogenicity, and the obstacles that must be overcome in curbing AA exposure and preventing associated cancers. Overall, this Review aims to strengthen the case for the implementation of prevention measures against AA's multifaceted, detrimental and potentially fully preventable effects on human cancer development.
The increased understanding of epigenetics has significantly advanced our understanding of cancer development, especially regarding environmental, occupational, and lifestyle exposures. Unlike genetic mutations, epigenetic changes may be reversible, making them critical mediators and promising targets for cancer prevention and control. This review synthesizes two decades of transformative research by the International Agency for Research on Cancer (IARC), which positioned the epigenome as a central focus in cancer epidemiology and mechanistic research among the 10 Key Characteristics (KCs) of carcinogens by the IARC Monographs program. From foundational in vitro and animal studies to large-scale population-based research, IARC researchers contributed to unraveling epigenetic mechanisms of carcinogenesis and identifying epigenetic biomarkers of exposures and cancer risk. We highlight progress in epigenetic biomarker development, mechanistic epigenomics, toxico-epigenomics, and the interplay between diet, microbiome, and epigenome. As IARC marks its 60th anniversary, this review underscores the growing role of epigenetics in guiding global cancer prevention efforts and public health strategies.