Another report has shown that N-terminal fragment of gp96 is immunologically sufficient module of gp96 [19]. Our work also indicated that the fusion protein including N-terminal fragment of gp96 can be used in immunotherapy of tumours and vaccine development. It was indicated that prophylactic immunization with adjuvant-free fusion protein HSP65E7 protects mice against challenge with TC-1 cells and that

these tumour-free animals are also protected against re-challenge dose of TC-1 cells [45]. Regarding to the obtained results in this study, adjuvant-free vaccination with rE7-NT-gp96 protein could be efficient for delaying the tumour occurrence and growth in C57BL/6 tumour mice model. IFN-γ cytokine has been shown to function critically in conferring potent immunity and antitumour effect to TC-1 tumours. It has been demonstrated that IFN-γ inhibit tumour

growth in vivo by R788 in vitro up-regulation of MHC class I molecules, as well as inducing inflammation at tumour sites [47, 48]. Consistently, our study also demonstrated Temsirolimus that high level of IFN-γ could describe potent antitumour effects against TC-1 tumour challenge. Heat shock proteins-based vaccines are a novel approach with a promising role in cancer therapy. Recently, several studies in Phase I and II clinical trials, on different malignancies, including colorectal cancer, metastatic melanoma, pancreatic cancer and non-Hodgkin’s lymphoma were carried out using autologous tumour-derived heat shock protein gp96-peptide complexes (HSPPC-96). This HSPs-based vaccine induced tumour-specific T cell responses in patients [38–41]. Tumour-derived HSP vaccine should be prepared individually for

each patient. To overcome this drawback, recombinant HSP-antigen protein vaccines have been developed in preclinical and clinical trials PIK3C2G [24, 45, 49–51]. Whole protein which is fused to HSP molecules by covalent linkage can be split into many different naturally processed short peptides in the MHC class I processing pathway. Therefore, recombinant HSP-antigen proteins are promising candidates for vaccines in populations with dissimilar MHC individuals [25]. Altogether, HSP-antigen fusion proteins have been successfully employed as vaccines to stimulate antigen-specific cytotoxic T cells without requiring exogenous adjuvants [52]. It has been shown that linkage between antigen and HSP leads to more significant adjuvant activity than co-administration of antigen and HSP which is due to the necessarily direct contact with the same APC [46, 53]. Fusion proteins comprising of the Mycobacteria-derived HSP linked to HPV16 E7 were applied for targeting antigens to APCs and thus improving APCs’ antigen uptake and presentation [45, 54]. More recently a fusion protein vaccine comprising of HPV16 E7 and M.