Immunotherapy-driven remodeling of the tumor immune microenvironment: Spatiotemporal heterogeneity and multidimensional dynamics.

Immunotherapy, by activating the patient's immune system to eliminate tumors, has become a revolutionary strategy in cancer treatment. Among immunotherapy, immune checkpoint blockade (ICB) and adoptive cell therapy (ACT) have demonstrated significant efficacy in various solid tumors and hematological malignancies. However, problems such as insufficient clinical response rate, acquired drug resistance, and immune-related adverse reactions have limited its wide application, which is closely related to the immunosuppressive network formed by the dynamic evolution of the tumor microenvironment (TME) during the treatment process. TME is not only a "sanctuary" for tumors, but also a core hub for regulating the function of immune cells. Recent studies have shown that the dynamic changes of TME have spatiotemporal heterogeneity in immunotherapy and generate favorable or unfavorable mechanisms during the process of tumor immunotherapy, thereby affecting the efficacy of immunotherapy. This review systematically integrates the dynamic trajectories of TME revealed by cutting-edge technologies such as scRNA-seq and spatial transcriptomics. It analyzes the spatiotemporal evolution laws of immune cell subsets under ICB treatment. This article aims to elaborate on the dynamic trajectory and phenotypic changes of the TME during the immunotherapy treatment, providing meaningful insights into cancer immunotherapy.