After being taken up by the tumor cells, catalase decomposes H2O2 into O2, thereby increasing the efficacy of radiotherapy, which generates tumor antigens after treatment, allowing for imiquimod, a TLR-7 agonist, to mount an antitumor immune response, as measured by an increase in TNF-α, IFN-γ, and IL-12 in a mouse model. This evidence concerns the gene CAT and neoplasm.