Novel Hydrogel-Mediated Lentiviral Gene Delivery via Intravesical Administration for Bladder Cancer Treatment

Background/Objectives: Bladder urothelial carcinoma is a frequent malignant tumor of the urinary system, characterized by its high rates of recurrence and resistance to chemotherapy. This study explored the beneficial effects of overexpressing WW domain-containing oxidoreductase (WWOX) in AY-27 cells encapsulated in an injectable gelatin hydrogel for potential therapeutic applications in bladder cancer. Methods: AY-27 cells were genetically transduced with lentiviruses (LV) to overexpress WWOX (LV-WWOX) and subsequently encapsulated in a gelatin hydrogel. The mechanical properties and morphology of the hydrogels were assessed using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The therapeutic efficacy of this approach was evaluated using an F344/AY-27 rat orthotopic bladder cancer model, in which the LV-WWOX-hydrogel (H-LV-WWOX) was administered via intravesical instillation. Results: The gelatin hydrogel formulation demonstrated excellent biocompatibility, stability, and controlled release. In a rat orthotopic model, intravesical instillation of H-LV-WWOX significantly enhanced local immune responses, resulting in notable tumor regression. Compared to the sham-treated group, this approach reduced systemic toxicity and improved overall treatment outcomes. The anticancer effect of WWOX can be attributed to its ability to amplify TNF-α-induced reactive oxygen species (ROS) generation. This ROS-mediated pathway leads to enhanced apoptosis and DNA damage in cancer cells, highlighting the potential mechanism through which WWOX exhibits tumor-suppressive activities. Conclusions: These findings support the therapeutic potential of WWOX overexpression in gelatin hydrogels for bladder cancer treatment and warrant further clinical investigation.