HAO1 and neoplasm: One is direct cutting‐off of blood supply at the tumor regime by blocking/destroying the blood vessels or inhibiting angiogenesis.[3] Another is to deplete essential nutrients in tumor.[4] As a type of oxidoreductase, glucose oxidase (GOx) presents intrinsic properties in converting glucose, oxygen, and water into gluconic acid, and simultaneously hydrogen peroxide is generated.[5] Given the crucial role of glucose metabolism in tumor growth, it is logic that the tumor would starve to death with direct glucose deprivation by GOx.