Immunological Mechanisms in Tumor Microenvironments

The tumour microenvironment (TME) comprises a dynamic network of malignant cells, stromal elements and diverse immune populations whose interactions dictate cancer progression and response to therapy. Innate immune cells such as macrophages, neutrophils and dendritic cells provide early surveillance but can be co-opted into protumoural phenotypes through local cytokine and metabolic cues. Adaptive populations, including cytotoxic T lymphocytes and regulatory T cells, undergo functional reprogramming within the TME, resulting in either tumour eradication or immune evasion. Key immunological processes include checkpoint receptor signalling, antigen presentation, cytokine networks, metabolic competition for nutrients and the formation of physical barriers by extracellular matrix components. Tumour-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) often accumulate and release factors that suppress T cell activation and promote angiogenesis. Conversely, successful immunotherapies aim to restore cytotoxic T cell function, re-educate suppressive myeloid cells and reconfigure the stromal landscape. Advances in multiplexed imaging and single-cell profiling have begun to resolve the spatial and temporal heterogeneity of these immune constituents, offering routes to more precise combination treatments and novel immune-modulating agents.

Research from Nature Portfolio

Recent studies have employed high-dimensional spatial transcriptomics to map the precise localisation of immune subtypes within solid tumours, revealing micro-niches enriched in exhausted T cells and regulatory macrophages that correlate with response to checkpoint blockade. Another line of investigation has defined the metabolic constraints on effector T cells in nutrient-depleted regions of the TME, showing that competition with cancer cells for glucose and amino acids undermines cytotoxic function. A landmark report has characterised a previously unrecognised checkpoint molecule expressed by tumour-infiltrating dendritic cells that attenuates antigen cross-presentation, providing a new target for combinatorial immunotherapy strategies. These insights underscore the integration of cell biology, metabolism and spatial architecture in shaping antitumour immunity.

Immunological Mechanisms in Tumor Microenvironments publication trend

The graph below shows the total number of articles in immunological mechanisms in tumor microenvironments across all publications each year (not limited to Nature Index journals).

Technical terms

Tumour microenvironment: The local ecosystem of cancer cells, stromal components and immune cells that influences tumour behaviour and therapy response.

Tumour-associated macrophages (TAMs): Macrophages within the TME that often adopt a suppressive phenotype, promoting angiogenesis and immune evasion.

Myeloid-derived suppressor cells (MDSCs): A heterogeneous group of immature myeloid cells that inhibit T cell function and foster tumour progression.

Checkpoint receptors: Inhibitory molecules on immune cells (e.g., PD-1, CTLA-4) whose engagement by ligands on tumour or stromal cells dampens antitumour immunity.

Spatial transcriptomics: A technique for mapping gene expression within intact tissue sections, preserving spatial relationships between cells.

References

1. Rapamycin Induces Phenotypic Alterations in Oral Cancer Cells That May Facilitate Antitumor T Cell Responses. Biomedicines (2024).
2. The Monocytes That Repopulate in Mice After Cyclophosphamide Treatment Acquire a Neutrophil Precursor Gene Signature and Immunosuppressive Activity. Frontiers in Immunology (2021).
3. Progression of Large Lymphoma Is Significantly Impeded with a Combination of Gemcitabine Chemotherapy and Dendritic Cells Intra-Tumor Vaccination. PLOS ONE (2015).