Oxidative Stress Pathways in Cancer: Lessons Learned from Heavy Metal Exposures

Background: Heavy metal exposure is a critical environmental health concern, contributing to oxidative stress and increasing cancer risk. Reactive oxygen species (ROS) generated by heavy metals disrupt cellular functions, leading to DNA damage, epigenetic alterations, and activation of oncogenic pathways.Objective: This review aimed to explore the mechanisms by which heavy metals induce oxidative stress and promote carcinogenesis, synthesizing current knowledge from experimental, epidemiological, and molecular studies.Methods: A review was conducted using PubMed, Scopus, and Web of Science databases to identify peer-reviewed articles published up to December 2024. Keywords included "heavy metals," "oxidative stress," "ROS," and "cancer risk." Studies were selected based on predefined inclusion criteria and assessed for quality using validated tools. Data synthesis focused on mechanistic insights, epidemiological evidence, and therapeutic strategies.Results: The review identified 60 relevant studies. Arsenic exposure was linked to a 2.5-fold increase in lung cancer risk, while cadmium exposure showed a 3.8-fold increase in breast cancer risk. Heavy metals induced ROS production, reduced antioxidant levels, and caused DNA strand breaks. Epidemiological data revealed strong correlations between heavy metal exposure and cancers, including lung, breast, skin, and bladder.Conclusion: Heavy metals significantly contribute to oxidative stress and carcinogenesis. Targeted interventions, including stricter environmental regulations and antioxidant therapies, are necessary to mitigate health risks