The overexpression of H2O2 within tumor cells is widely acknowledged and may be associated with DNA damage, abnormal proliferation, and tumor metastasis.36 Catalase (CAT) is one of the fundamental oxidoreductases in the human body, and possesses the capability to decompose H2O2 into O2 and H2O (seen in Eq. The gene discussed is CAT; the disease is neoplasm.