Growth inhibitory effect of an injectable hyaluronic acid-tyramine hydrogels incorporating human natural interferon-α and sorafenib on renal cell carcinoma cells.

Immunotherapy including interferon-alpha (IFN-α) is one of the treatment options for metastatic renal cell carcinoma (mRCC) patients. Despite clinical benefits for the selected patients, IFN-α therapy has some problems, such as poor tolerability and dose-limiting adverse effects. In addition, the frequent injections reduce a patient's quality of life and compliance. Recently, an injectable and biodegradable hydrogel system to prolong drug release is reported. In this study, we investigated the anticancer effect of IFN-α (Sumiferon®)-incorporated hyaluronic acid-tyramine (HA-Tyr) hydrogels in human RCC-xenografted in nude mice. We also evaluated the synergistic efficacy of IFN-α-incorporated HA-Tyr hydrogels+sorafenib in this model. IFN-α-incorporated HA-Tyr hydrogels+sorafenib most effectively inhibited tumor growth on human RCC cells xenografted in nude mice. In addition, IFN-α-incorporated HA-Tyr hydrogels+sorafenib inhibited the proliferation of tumor in nude mice by inducing apoptosis and the suppression of angiogenesis. Our results suggest a possibility that HA-Tyr hydrogel drug delivery system prolongs the biological half-life of natural human IFN-α and enhances its anticancer effects on human RCC cells. STATEMENT OF SIGNIFICANCE: The scope of this study is to provide an alternative approach to improve the anticancer efficacy in renal cell carcinoma (RCC) treatment by using hyaluronic acid-tyramine (HA-Tyr) hydrogel drug delivery system. We investigated the anticancer effect of natural interferon-α (IFN-α)-incorporated HA-Tyr hydrogels in RCC cells. We also evaluated the synergistic efficacy of natural human IFN-α-incorporated HA-Tyr hydrogels+sorafenib. We demonstrated that HA-Tyr hydrogel system is able to release natural human IFN-α in sustained manner and enhances its anticancer effects on human RCC cells. In addition, we suggested that IFN-α-incorporated HA-Tyr hydrogels+sorafenib exhibited most effectively anticancer effects. Hence, we believe that this approach could be applied to treatment with RCC in the future.