Cancer immunotherapy: Current progress and future perspectives

Cancer immunotherapy has revolutionized cancer treatment by harnessing the host immune system to recognize and eliminate tumor cells. In recent years, significant progress has been achieved in multiple immunotherapeutic modalities, particularly immune checkpoint inhibitors (ICIs), cancer vaccines, oncolytic virus therapies (OVs), and adoptive cell therapies (ACTs). Extensive clinical trial data proved that immunotherapy brings durable responses and survival benefits across various malignancies, supporting the official approval of numerous immunotherapy agents for cancer treatment. Despite these advances, major challenges remain, including immune-related toxicities, tumor heterogeneity, and treatment resistance, which restrict the therapeutic efficacy and tolerability. To address these limitations, emerging strategies are being actively explored, including rational combination therapies, next-generation immune cell engagers, and engineered innate immune cellular products. In this review, we comprehensively summarize recent progress in the development of cancer immunotherapy and discuss the bottlenecks and potential strategies for each therapeutic approach. Available clinical data are highlighted to provide a more intuitive understanding of the efficacy and safety of these treatments, thereby facilitating future broader application of immunotherapy. Ultimately, such insights may guide the more effective and safer use of current therapies and support the development of next-generation therapeutic alternatives.