Cancer immunotherapy

Cancer immunotherapy encompasses a broad class of therapeutic strategies that harness or augment the body's own immune system to recognize, target, and eliminate malignant cells. Unlike conventional treatments such as chemotherapy, radiotherapy, and surgery, immunotherapy operates through immune-specific mechanisms—activating cytotoxic T cells (CD8+ T cells), natural killer cell, dendritic cells, and other immune effectors against tumors—and can cause immune-mediated toxicities. The foundational principles rest on overcoming tumor immune evasion: cancer cells exploit checkpoints such as the PD-1/PD-L1 axis, suppress antigen presentation, and remodel the tumor microenvironment (TME) to exclude or exhaust infiltrating lymphocytes. Key pillars of modern cancer immunotherapy include checkpoint inhibitor (targeting Programmed cell death 1 (PD-1), CD274 molecule, and CTLA-4), chimeric antigen receptor T cell (CAR-T) therapy, cancer vaccines, bispecific and trispecific antibody engagers, and innate immune pathway agonists such as activators of the cGAS-STING pathway.

The clinical impact of cancer immunotherapy has been transformative across multiple tumor types. Agents such as nivolumab, ipilimumab, atezolizumab, and durvalumab have demonstrated durable responses in patients with advanced melanoma, lung cancer, bladder cancer, and other malignancies. However, substantial inter-patient response heterogeneity limits benefit to specific subsets, driving intense investigation into predictive biomarkers, combination strategies, and novel delivery systems. Ongoing research seeks to extend immunotherapy's reach to immunologically "cold" tumors—those with sparse lymphocytic infiltration—by reprogramming the TME, enhancing antigen presentation, and synergizing immune activation with targeted agents and nanomedicine platforms.