The role of NADPH oxidase in cancer is multifaceted. It contributes to cancer by promoting oxidative stress, which can lead to DNA damage, mutations, and genomic instability. These changes can drive the initiation and progression of cancer. Furthermore, NADPH oxidase-derived ROS can activate various signaling pathways that support cell proliferation and survival, angiogenesis, and metastasis, making it a potential target for cancer therapy.