Topoisomerase II alpha as a universal tumor antigen: antitumor immunity in murine tumor models and H-2Kb-restricted T cell epitope

Department of Microbiology and Immunology, The Catholic University of Korea, Banpo-dong, Seocho-gu, Seoul, Korea.
Cancer Immunology and Immunotherapy (Impact Factor: 3.94). 11/2009; 59(5):747-57. DOI: 10.1007/s00262-009-0795-3
Source: PubMed

ABSTRACT Topoisomerase II alpha (Top2alpha) is an attractive candidate to be used as a tumor antigen for cancer immunotherapy, because it is abundantly expressed in various tumors and serves as a target for a number of chemotherapeutic agents. In this study, we demonstrated the immunogenicity of Top2alpha, using dendritic cells (DC) electroporated with RNA encoding the Top2alpha C-terminus (Top2alphaCRNA/DC). Top2alphaCRNA/DC were able to demonstrate in vitro stimulation of T cells from mice that were previously vaccinated with Top2alpha-expressing tumor lysate-pulsed DC. Vaccination with Top2alphaCRNA/DC induced Top2alpha-specific T cell responses in vivo as well as antitumor effects in various murine tumor models including MC-38, B16F10, and GL26. DC pulsed with p1327 (DSDEDFSGL), defined as an epitope presented by H-2K(b), also induced Top2alpha-specific immune responses and antitumor effects. Based on these data, Top2alpha is suggested to be a universal target for cancer immunotherapy.

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