Versatile hydrogel-based drug delivery platform for multimodal cancer therapy from bench to bedside

Hydrogel exhibits a promising application prospect for multimodal cancer therapy in clinic compared with other conventional drug delivery platforms, which is predominantly attributed to its excellent biocompatibility, local injectability and retention, sustained drug release behavior, multiple administration approaches, and flexible drug loading capacity. Hydrogel can be further classified into physical, chemical, and multiple crosslinked hydrogels according to the formation mechanisms. The emergence of hydrogel enables antineoplastic agents to be delivered in much broader routes compared with numerous traditional carriers. Intratumoral injection, peritumoral injection, and postoperative implantation are regarded as the three momentous approaches for administrating macroscopic hydrogel, while nanoscopic hydrogel can also be applied through intravenous injection. In addition, both monotherapy and combination therapy against cancer are available to be realized through hydrogel delivery system, providing a valuable opportunity to enhance antitumor effect and achieve synergistic efficacy. Recently, several hydrogel products have already been approved by FDA, exerting essential roles against cancer in clinic. Meanwhile, there have also been various types of hydrogel delivery systems for cancer therapy in clinical trial stage. To sum up, hydrogel is a versatile drug delivery platform with good clinical translation potential, offering a promising and meaningful strategy for cancer therapy.