Curcumin Enhances the Antitumoral Effect Induced by the Recombinant Vaccinia Neu Vaccine (rV-T) in Mice with Transplanted Salivary Gland Carcinoma Cells.

The survival rate for head and neck cancer patients has not substantially changed in the last two decades. We previously showed that two rV-T intratumoral injections induced an efficient antitumor response and rejection of transplanted Neu (rat oncogene-encoded protein)-overexpressing salivary gland tumor cells in BALB-T mice (BALB/c mice transgenic for the rat oncogene). However, reiterated poxviral vaccinations increase neutralizing antibodies to viral proteins in humans that prevent immune response against the recombinant antigen expressed by the virus. Curcumin (CUR) is a polyphenol with antineoplastic and immunomodulatory properties. The aim of this study was to employ CUR administration to boost the anti-Neu immune response and anticancer activity induced by one rV-T intratumoral vaccination in BALB-T mice. Here, we demonstrated that the combined rV-nT+CUR treatment was more effective at reducing tumor growth and increasing mouse survival, anti-Neu humoral response, and IFN-γ/IL-2 T-cell release in vitro than the individual treatment. rV-T+CUR-treated mice showed an increased infiltration of CD4/CD8 T lymphocytes within the tumor as compared to those that received the individual treatment. Overall, CUR enhanced the antitumoral effect and immune response to Neu induced by the rV-T vaccine in mice. Thus, the combined treatment might represent a successful strategy to target ErbB2/Neu-overexpressing tumors.