As an antioxidant, Fucoidan protects cells against oxidative stress by scavenging superoxide radicals24; inducing expression of the anti-oxidant nuclear factor erythroid-2-related factor 2 and that of its target gene, superoxide dismutase25; and suppressing the transforming growth factor β (TGF-β)/Smad pathway26, which prevents reactive oxidative species (ROS) generation in cancer cells and ROS release into the TME27. The gene discussed is TGFB1; the disease is cancer.