Dendritic cell immunotherapy advances for solid tumors: Vaccination and modulation

Dendritic cells (DCs) are potent antigen-presenting cells, key for inducing anti-tumoral immune responses in the tumor microenvironment (TME) and tumor-draining lymph nodes. Within the TME, immunosuppressive signals often render DCs dysfunctional, hindering their propagation of T cell-mediated cancer cell death and tumor regression. DC-based immunotherapy has been investigated for over two decades, aiming to induce anti-tumor immunity by directly delivering DCs or antigens through vaccination or by enhancing the anti-tumor functions of existing DCs within the TME. Despite some progress, clinical benefit in many patients is still limited. As our understanding of the complex interactions that occur in the TME deepens and new technologies emerge, novel DC immunotherapy strategies are continuously being developed and advanced into clinical trials. This review provides an updated summary of the latest advances in these therapies, identifying trends that correlate with successful outcomes, as well as the challenges still being faced in the field.