Gene Expression of B16F10 Induced by Treatment with 5-aza-2'-deoxycytidine

Sohn, Jin Sik; Song, Dal Won; Kim, Tae Jong; Chae, Han Soo; Park, Jong Wook

Abstract

BACKGROUND AND OBJECTIVES: The goal of tumor vaccine is to activate immune system specifically against proteins expressed by a tumor, and many types of vaccines such as gene modified vaccines have been developed to increase immunogenicity of vaccine. We studied to determine whether or not 5-aza-2'-deoxycytidine (ADC) can increase the immunogenicity of B16F10 melanoma cell. MATERIALS AND METHOD: B16F10 cell was treated with ADC for the induction of DNA demethylation. An ADC treated B16F10 melanoma cell was analyzed first using the reverse transcriptase-polymerase chain reaction (RT-PCR) technique to evaluate the gene expression of tumor antigen (MAGE-2, MAGE-5) and immunity-enhancing cytokines (GM-CSF, IL-12), and then by flow cytometry to evaluate the expression of MHC and B7 that are responsible for antigen expression and T cell activation on B16F10 cell surface. In order to evaluate vaccination effect of ADC-treated B16F10 vaccine, each mouse group were injected with PBS, ADC, B16F10 vaccine or B16F10-ADC vaccine and they were also challenged with live B16F10 cell 7 days after vaccination. On the 20th day after live B16F10 cell challenge, the tumor mass size and the mouse survival period were determined.
RESULTS
ADC treatment for B16F10 melanoma cell increased expression of MHC and B7. ADC treatment also increased gene expression of MAGE-2, MAGE-5, GM-CSF and IL-12. The growth of tumor mass was decreased and the mouse survival period was elongated in B16F10-ADC vaccine immunized group.
CONCLUSION
ADC treatment may increase immunogenicity of B16F10 cell, and B16F10-ADC vaccine immunization can induce anti-cancer immunity in vivo.