PRF1 and malignant colon neoplasm: Moreover, therapeutic strategies directly targeting Th9/IL-9 have been explored in non-autoimmune settings—for instance, intratumoral delivery of IL-9 via an oncolytic vaccinia virus in a colon cancer mouse model demonstrated antitumor effects as evidenced by the increased expression of IFN-γ, granzyme B, and perforin as well as a higher proportion of regulatory T cells (90).