Restoration of MHC-I on Tumor Cells by Fhit Transfection Promotes Immune Rejection and Acts as an Individualized Immunotherapeutic Vaccine Garrido Torres-Puchol, Federico Pulido, María MHC-I restoration Fhit Antitumor immunity Immune profile Cytotoxic T lymphocytes Immunotherapy Vaccines The authors thank I. Linares, V. Sanz, A.B. Rodriguez, A.I. Rodriguez and E. Arias for technical advice and R. Davies for editorial assistance. The capacity of cytotoxic-T lymphocytes to recognize and destroy tumor cells depends on the surface expression by tumor cells of MHC class I molecules loaded with tumor antigen peptides. Loss of MHC-I expression is the most frequent mechanism by which tumor cells evade the immune response. The restoration of MHC-I expression in cancer cells is crucial to enhance their immune destruction, especially in response to cancer immunotherapy. Using mouse models, we recovered MHC-I expression in the MHC-I negative tumor cell lines and analyzed their oncological and immunological profile. Fhit gene transfection induces the restoration of MHC-I expression in highly oncogenic MHC-I-negative murine tumor cell lines and genes of the IFN-γ transduction signal pathway are involved. Fhit-transfected tumor cells proved highly immunogenic, being rejected by a T lymphocyte-mediated immune response. Strikingly, this immune rejection was more frequent in females than in males. The immune response generated protected hosts against the tumor growth of non-transfected cells and against other tumor cells in our murine tumor model. Finally, we also observed a direct correlation between FHIT expression and HLA-I surface expression in human breast tumors. Recovery of Fhit expression on MHC class I negative tumor cells may be a useful immunotherapeutic strategy and may even act as an individualized immunotherapeutic vaccine. 2020-09-01T11:27:20Z 2020-09-01T11:27:20Z 2020-06-12 journal article Pulido, M., Chamorro, V., Romero, I., Algarra, I., Collado, A., Garrido, F., & Garcia-Lora, A. M. (2020). Restoration of MHC-I on Tumor Cells by Fhit Transfection Promotes Immune Rejection and Acts as an Individualized Immunotherapeutic Vaccine. Cancers, 12(6), 1563. [doi: 10.3390/cancers12061563] http://hdl.handle.net/10481/63263 10.3390/cancers12061563 eng http://creativecommons.org/licenses/by/3.0/es/ open access Atribución 3.0 España MDPI