Reactive oxygen species (ROS) play a critical role in tumor progression by influencing cellular functions such as proliferation, survival, migration, and DNA damage. While ROS can promote tumorigenesis by increasing cell proliferation and inducing genetic mutations, they also have anti-tumorigenic effects by inducing cell death and senescence. The balance between these effects depends on the type, concentration, and location of ROS within cells. Tumor cells produce higher levels of ROS, and oxidative stress is often present in tumors, suggesting a complex interplay between ROS and cancer development. ROS are involved in various signaling pathways that regulate oncogenic processes. They can activate intracellular signaling cascades that promote tumor growth and metastasis, and they also contribute to the regulation of cell cycle, apoptosis, and DNA repair. ROS can be generated by various enzymatic systems, including NADPH-oxidase, thymidine phosphorylase, and mitochondrial respiration. Enzymes such as catalase and MnSOD help detoxify ROS, but their expression or activity is altered in tumor cells, contributing to oxidative stress. ROS also influence tumor metastasis by modulating cell adhesion, migration, and the expression of matrix metalloproteinases (MMPs), which facilitate tumor invasion. Additionally, ROS can regulate angiogenesis, which is essential for tumor growth. The role of ROS in tumor progression is further complicated by their ability to induce both pro- and anti-apoptotic signals, depending on the cellular context. ROS are also involved in the regulation of transcription factors such as NF-κB, AP-1, and STAT3, which control gene expression related to cell survival, proliferation, and metastasis. The activation of these factors by ROS can lead to the development of cancer. Antioxidants such as resveratrol have been shown to inhibit ROS production and reduce tumor growth, suggesting their potential as chemopreventive agents. In summary, ROS are multifaceted molecules that influence tumor progression through various mechanisms, including DNA damage, cell signaling, and the regulation of cell survival and death. Understanding the complex roles of ROS in cancer is crucial for developing new therapeutic strategies targeting oxidative stress in tumor cells.Reactive oxygen species (ROS) play a critical role in tumor progression by influencing cellular functions such as proliferation, survival, migration, and DNA damage. While ROS can promote tumorigenesis by increasing cell proliferation and inducing genetic mutations, they also have anti-tumorigenic effects by inducing cell death and senescence. The balance between these effects depends on the type, concentration, and location of ROS within cells. Tumor cells produce higher levels of ROS, and oxidative stress is often present in tumors, suggesting a complex interplay between ROS and cancer development. ROS are involved in various signaling pathways that regulate oncogenic processes. They can activate intracellular signaling cascades that promote tumor growth and metastasis, and they also contribute to the regulation of cell cycle, apoptosis, and DNA repair. ROS can be generated by various enzymatic systems, including NADPH-oxidase, thymidine phosphorylase, and mitochondrial respiration. Enzymes such as catalase and MnSOD help detoxify ROS, but their expression or activity is altered in tumor cells, contributing to oxidative stress. ROS also influence tumor metastasis by modulating cell adhesion, migration, and the expression of matrix metalloproteinases (MMPs), which facilitate tumor invasion. Additionally, ROS can regulate angiogenesis, which is essential for tumor growth. The role of ROS in tumor progression is further complicated by their ability to induce both pro- and anti-apoptotic signals, depending on the cellular context. ROS are also involved in the regulation of transcription factors such as NF-κB, AP-1, and STAT3, which control gene expression related to cell survival, proliferation, and metastasis. The activation of these factors by ROS can lead to the development of cancer. Antioxidants such as resveratrol have been shown to inhibit ROS production and reduce tumor growth, suggesting their potential as chemopreventive agents. In summary, ROS are multifaceted molecules that influence tumor progression through various mechanisms, including DNA damage, cell signaling, and the regulation of cell survival and death. Understanding the complex roles of ROS in cancer is crucial for developing new therapeutic strategies targeting oxidative stress in tumor cells.