Tumor Microenvironment and Immune Response in Colorectal Cancer

The tumour microenvironment in colorectal cancer encompasses a dynamic network of malignant cells, stromal fibroblasts, endothelial cells, extracellular matrix and infiltrating immune populations. Interactions within this niche govern tumour growth, invasion and metastasis. Immune components range from cytotoxic T lymphocytes and helper T cells that can restrain tumour progression, to regulatory T cells, myeloid-derived suppressor cells and tumour-associated macrophages that foster immune evasion. Cancer-associated fibroblasts remodel the extracellular matrix and secrete cytokines that modulate immune cell recruitment and activation, while angiogenic factors support neovascularisation. Genetic and epigenetic alterations in tumour cells generate neoantigens that may elicit an adaptive immune response, yet tumours often exploit checkpoint pathways to blunt T-cell cytotoxicity. Microsatellite instability and chromosomal instability subtypes display distinct immune signatures, influencing prognosis and response to immunotherapy. A comprehensive understanding of this ecosystem is critical for developing precision interventions that re-educate immune cells, disrupt stromal support and improve patient survival on a global scale.

Research from Nature Portfolio

Recent advances in spatial systems biology have delivered tools for risk stratification and mechanistic insight. A multiplexed imaging study applied a computational platform to map spatial domains of primary colorectal tumours and identified distinct microenvironmental niches predictive of five-year recurrence risk. This approach revealed networks of ligand–receptor interactions among immune, stromal and malignant cells, highlighting spatially organised niches of immune exclusion and pro-inflammatory signalling. In parallel, preclinical validation of a novel small-molecule inhibitor demonstrated the potential to target tumour angiogenesis and modulate immune mediators within the microenvironment. By suppressing neovascular growth and reducing pro-angiogenic cytokine release in patient-derived explants and xenograft models, this agent exemplifies how disrupting vascular support can reprogramme immune cell infiltration and suppress CRC progression.

Tumor Microenvironment and Immune Response in Colorectal Cancer publication trend

The graph below shows the total number of articles in tumor microenvironment and immune response in colorectal cancer across all publications each year (not limited to Nature Index journals).

Technical terms

Tumour microenvironment (TME): The local milieu of non-malignant cells, matrix and signalling molecules surrounding tumour cells.

Immune checkpoint inhibitors (ICIs): Therapeutic antibodies that block inhibitory pathways on T cells to restore antitumour immunity.

Microsatellite instability (MSI): A genomic phenotype caused by defects in mismatch-repair enzymes, leading to high mutation rates and neoantigen generation.

Dendritic cell (DC): A professional antigen-presenting cell that primes T-cell responses and orchestrates adaptive immunity.

Neoantigen: A novel peptide derived from tumour-specific mutations, recognised as non-self by the immune system.

References

1. The Heterocellular Emergence of Colorectal Cancer. Trends in Cancer (2017).
2. Immunogenomic Classification of Colorectal Cancer and Therapeutic Implications. International Journal of Molecular Sciences (2017).
3. Spatial domain analysis predicts risk of colorectal cancer recurrence and infers associated tumor microenvironment networks. Nature Communications (2020).
4. Preclinical validation of the small molecule drug quininib as a novel therapeutic for colorectal cancer. Scientific Reports (2016).
5. Can immunotherapy reinforce chemotherapy efficacy? a new perspective on colorectal cancer treatment. Frontiers in Immunology (2023).
6. Unraveling Resistance to Immunotherapy in MSI-High Colorectal Cancer. Cancers (2023).
7. An Activated Dendritic-Cell-Related Gene Signature Indicative of Disease Prognosis and Chemotherapy and Immunotherapy Response in Colon Cancer Patients. International Journal of Molecular Sciences (2023).