%0 Journal Article %T Combination Immunotherapy with 4-1BBL and CTLA-4 Blockade for the Treatment of Prostate Cancer %A Kuang Youlin %A Zhang Li %A Weng Xiaodong %A Liu Xiuheng %A Zhu Hengchen %J Clinical and Developmental Immunology %D 2012 %I Hindawi Publishing Corporation %R 10.1155/2012/439235 %X Immune regulation has been shown to be involved in the progressive growth of some murine tumours. Interruption of immune regulatory pathways via activation of 4-1BB or cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) blockade appears to be a promising strategy for cancer immunotherapy. In this study, we examined the effectiveness of 4-1BBL-expressing tumor cell vaccine in combination with CTLA-4 blockade on rejection of murine prostate cancer RM-1. We found that the combination of both a vaccine consisting of 4-1BBL-expressing RM-1 cells and CTLA-4 blockade resulted in regression of RM-1 tumors and a significant increase in survival of the tumour cell recipients, compared to that of either treatment alone. The combined vaccination resulted in higher CTL against RM-1 cells and increased secretion of IFN-, TNF-, and IL-2 in the mix-cultured supernatant. These results suggest that combining activation of 4-1BB and blockade of CTLA-4 may offer a new strategy for prostate cancer immunotherapy. %U http://www.hindawi.com/journals/cdi/2012/439235/