Engineered nanobiotechnology for cancer immunotherapy

Despite the clinical success of immune checkpoint blockade and chimeric antigen receptor T-cell therapies, solid tumors frequently remain poorly responsive due to multi-step failures in initiating, maintaining, and executing immune responses in vivo. Overcoming these barriers requires organizing immune cues into productive biological relationships rather than simply intensifying systemic immune stimulation. This review examines how engineered nanobiotechnology addresses this central challenge by spatially and temporally coordinating key immune processes. Adopting a biology-driven and engineering-enhanced perspective, we analyze nanoscale interventions across four critical phases of antitumor immunity. Immune initiation engineering optimizes antigen processing and localized delivery to promote productive T-cell priming. To sustain these responses, targeted nanosystems reprogram lymphocytes and myeloid cells toward functional effector states in vivo. At the cellular interface, engineered platforms spatially coordinate immune recognition and effector engagement, while tumor microenvironment (TME) engineering remodels the suppressive niche to support tumor-specific immune activation. By organizing these advances through a process-centered engineering framework, we elucidate how nanobiotechnology can convert otherwise localized, transient, or poorly coordinated immune stimulation into integrated antitumor immunity. Finally, we discuss emerging clinical examples and translational requirements, highlighting how pharmacodynamic immune readouts, patient stratification, and manufacturable designs will drive next-generation nano-immunotherapies toward solid-tumor treatment.