The Protective and Therapeutic Effect of DNA Vaccine Derived From Immunogenic Components of BORIS Antigen on Colon Cancer in Balb/C Mice

Immunotherapy is a new strategy to prevent and treat cancers. Cancer-testis antigens has gained lots of attention as the target of anti-cancer immunotherapy. In this study, Brother of regulator of imprinted sites (BORIS) cancer-testis antigen was used to design a DNA vaccine using bioinformatics tools, and its efficacy was assessed in murine colon cancer model in Balb/C mice.

In our previous study, the immunodominant regions of the BORIS antigen were identified. They were used to design a DNA vaccine inside the pcDNA3.1 plasmid after appropriate modifications and reverse translation. The DNA vaccine was used to immunized BALB/c mice four times at weekly intervals. 14 days after the last injection, the levels of specific cytokines and antibodies were measured. Moreover, to evaluate the protective effect of the DNA vaccine, colorectal cancer cells (CT26) were injected into mice, and tumors’ growth progression evaluated for 28 days.

Vaccination with this multiepitope DNA vaccine increased the level of gamma interferon (IFN-γ) and interleukin 4 (IL-4) cytokines (P < 0.001) and specific antibodies [immunoglobulin G1 (IgG1), IgG2a, IgG total] (P < 0.001) compared to control groups [phosphate buffered saline (PBS) and pcDNA3.1-VAC]. Moreover, mean tumors volume significantly decreased (P < 0.001) in the DNA vaccine immunized group compared to control groups.

This study suggests that the use of a BORIS antigen-derived DNA vaccine can be used as a strategy to induce a significant anti-tumor immune response, and inhibit murine colon tumors growth.