Epigenetic remodeling combined with photodynamic therapy elicits anticancer immune responses

Photodynamic therapy has been shown to induce strong immunity against tumor cells expressing exogenous tumor-associated antigens (TAAs), including P1A antigen. Cancer cells can evade the immune system by epigenetic silencing of TAAs, while DNA methyltransferase inhibitors, such as 5-aza-2'-deoxycytidine (5-aza-dC) can restore the expression of silenced or downregulated TAA. Thus, epigenetic remodeling with 5-aza-dC combined with PDT can elicit robust and durable antitumor immunity.