The mutation in HSCs that gives rise to CHIP can be driven by various genetic alterations that accumulate over time. These somatic mutations often affect genes involved in crucial cellular processes such as proliferation and differentiation, which may not only promote clonal expansion but also confer survival advantages under certain stress conditions. Inflammation, a hallmark of aging, creates an environment that can selectively favor the expansion of CHIP clones, thus supporting the theory that CHIP might serve as an adaptive response to the challenges posed by chronic inflammation.

Emerging evidence indicates that individuals with CHIP have an elevated risk of developing hematological malignancies, including acute myeloid leukemia and myelodysplastic syndromes. The connection between CHIP and these malignancies is multifaceted, involving the interplay of tumor suppressor pathways and pro-oncogenic signaling cascades that are modified by the inflammatory milieu. This not only underscores the potential of CHIP as a biomarker for cancer risk but also highlights the need for further clinical investigation of patients exhibiting this condition.

In addition to hematological malignancies, CHIP’s influence extends to various chronic diseases, most notably cardiovascular disorders. The presence of CHIP-associated clones has been linked to increased inflammatory markers, suggesting a causal relationship between clonal expansion and the development of cardiovascular pathologies. This inflammatory state may be driven by the activity of mutant HSCs, which become hyper-responsive to inflammatory signals and contribute to an overall state of chronic, low-grade inflammation termed “inflammageing.”

Inflammageing is characterized by a gradual increase in systemic inflammation, which is thought to contribute to the decline in organ function observed in older adults. The relationship between CHIP and inflammageing is particularly intriguing, as it raises questions about the potential for CHIP mutations to either exacerbate or mitigate the effects of chronic inflammation on normal HSC function. While normal HSCs are often inhibited by inflammatory signals, evidence suggests that CHIP-mutant HSCs may not only withstand these detrimental effects but may also benefit from them, thus promoting their own expansion.

In the context of inflammageing and cellular aging, CHIP may act as a double-edged sword. On one hand, the clonal expansion of mutant HSCs provides a reservoir of functionally altered cells that could contribute to enhanced blood cell production in response to inflammatory stressors. On the other hand, this process could compromise the function and regenerative potential of the normal HSC pool, leading to diminished hematopoietic resilience over time. The challenge lies in delineating these complex interactions, as an in-depth understanding is crucial for developing targeted therapeutic interventions for older adults.

As the research landscape continues to evolve, there is a growing recognition of the need for longitudinal studies that track the progression of CHIP and its clinical consequences. The identification of specific biomarkers associated with CHIP could facilitate early detection and risk stratification for patients predisposed to hematological malignancies and other age-related diseases. Additionally, exploring the therapeutic potential of targeted interventions that address the inflammatory component of CHIP may reveal novel strategies to alter disease trajectories in at-risk populations.

The translational implications of the CHIP and inflammageing interplay extend beyond hematopoietic malignancies and cardiovascular diseases. Researchers are beginning to uncover potential links between CHIP and other organ systems, including neurodegenerative diseases and metabolic disorders. Understanding how these interactions manifest at the cellular and molecular levels could pave the way for holistic approaches to treat and prevent a range of diseases that commonly afflict the aging population.

Current advancements in single-cell genomic technologies are revolutionizing our ability to investigate the heterogeneity of clonal blood populations and their interactions with the microenvironment. These cutting-edge techniques allow for detailed characterization of mutated clones and their functional capacities, providing insights that might inform personalized treatment strategies. As our understanding deepens, it is likely that we will see a paradigm shift in the way we approach diseases associated with aging, with a stronger focus on the role of clonal hematopoiesis and its broader implications on health.

Moreover, the engagement of the immune system in inflammageing and its relationship with CHIP cannot be overlooked. Immune cells, particularly those of the myeloid lineage, play pivotal roles in shaping the inflammatory environment and influencing HSC behavior. Investigating how CHIP-mutant HSCs communicate with immune cells within the bone marrow niche can yield important insights into the maintenance of hematopoietic homeostasis and the potential disruption of this delicate balance in pathological states.

As we look towards the future, interdisciplinary collaboration between researchers, clinicians, and public health officials will be essential to harness the knowledge gained from CHIP studies effectively. By integrating findings from molecular biology, genetics, immunology, and epidemiology, we can develop comprehensive models that address the multifactorial nature of diseases associated with ageing. Such collaborative efforts will enable us to envision innovative solutions that not only target the molecular drivers of CHIP but also tackle the systemic inflammatory processes that underpin many age-related conditions.

In conclusion, the interplay between clonal haematopoiesis of indeterminate potential and inflammageing presents a critical avenue for research and therapeutic exploration. As our understanding of the underlying mechanisms continues to evolve, we are better equipped to address the challenges posed by aging and its associated diseases, ultimately improving health outcomes for the aging population. More research is needed to investigate the clinical implications of these findings, with the hope that targeted interventions will pave the way for a healthier ageing process.

Subject of Research: Clonal haematopoiesis of indeterminate potential and its relationship with inflammageing and its impact on age-related diseases.

Article Title: Inflammageing and clonal haematopoiesis interplay and their impact on human disease.

Article References: Hajishengallis, G., Chavakis, T. Inflammageing and clonal haematopoiesis interplay and their impact on human disease.
Nat Rev Mol Cell Biol (2026). https://doi.org/10.1038/s41580-025-00936-y

Image Credits: AI Generated

DOI: 10.1038/s41580-025-00936-y

Keywords: Clonal haematopoiesis, inflammageing, hematopoietic stem cells, somatic mutations, chronic inflammation, ageing diseases, cardiovascular disorders, hematological malignancies, immune system interactions.

The phenomenon at the center of this discovery is clonal haematopoiesis of indeterminate potential (CHIP). CHIP emerges when hematopoietic stem cells in the bone marrow acquire somatic mutations as individuals age and are exposed to environmental stresses. Although CHIP has been previously associated with increased risks for cardiovascular diseases and blood cancers, its role in the evolution of solid tumors remained unclear until now. By leveraging large-scale genomic and clinical data sets, the researchers were able to establish that CHIP mutations are present in the circulating blood of cancer patients and critically, in a substantial proportion of tumor-infiltrating immune cells.

This comprehensive study incorporated data from over 400 lung cancer patients enrolled in the Cancer Research UK-funded TRACERx and PEACE trials, as well as an expansive cohort of nearly 49,000 patients with various cancer types treated at Memorial Sloan Kettering Cancer Center. Blood samples from these cohorts underwent deep sequencing to identify the presence of CHIP mutations. Matching the genomic data with clinical outcomes uncovered a stark correlation: patients harboring CHIP mutations exhibited markedly reduced overall survival, independent of their age or tumor stage at diagnosis. This observation introduced a previously unappreciated dimension of how age-related clonal blood mutations can influence cancer prognosis.

Digging deeper, the team identified a subset of patients in whom these mutated blood cells had physically infiltrated the tumor microenvironment, a situation they termed tumor-infiltrating clonal haematopoiesis (TI-CH). Remarkably, about 42% of patients with CHIP demonstrated TI-CH, highlighting the significant cross-talk between the hematopoietic system and tumor biology. It was TI-CH, rather than CHIP alone, that emerged as a powerful predictor of cancer relapse and mortality, thus emphasizing the biological relevance of these infiltrating mutant cells.

Further investigation into metastatic sites, studied through postmortem analyses under the PEACE protocol, reinforced the notion that TI-CH is not confined to primary tumors but is prevalent in secondary lesions where cancer dissemination occurs. The presence of TI-CH mutations in metastatic foci implicates these mutant myeloid cells as active players in the terminal phases of cancer progression, possibly facilitating the establishment and persistence of aggressive disease phenotypes.

Crucially, the study dissected the cellular composition and genotypic profiles of these tumor-infiltrating cells. Myeloid cells—a diverse group of immune cells involved in inflammation and tissue remodeling—were found to be the predominant cell type housing CHIP mutations within the tumor microenvironment. Unlike cytotoxic lymphocytes that target and eliminate cancer cells, myeloid cells often adopt immunosuppressive or tumor-supportive roles. This shift in immune landscape could enable tumor cells to evade immune surveillance and accelerate their growth and spread.

Among the mutated genes identified within TI-CH cells, TET2 stood out due to its critical regulatory functions in hematopoiesis and epigenetic control. TET2 mutations were disproportionately represented in tumor-infiltrating myeloid populations compared to other immune subsets. By analyzing hundreds of single cells from tumors of patients with TI-CH, the researchers confirmed that these alterations were predominantly restricted to myeloid cells, indicating a selective advantage or tropism for TET2 mutant cells to colonize the tumor microenvironment.

To translate these observations into functional insights, the research team collaborated with experts on blood cancers and CHIP at the Crick Institute, including the laboratory led by Dominique Bonnet. Together, they engineered three-dimensional lung tumor organoids co-cultured with TET2 mutant myeloid cells, effectively mimicking the complex interactions within human tumors. The presence of mutant myeloid cells induced pronounced remodeling of the tumor microenvironment and accelerated organoid growth, providing experimental evidence that TET2 mutations in infiltrating immune cells actively foster tumor progression rather than serving as passive bystanders.

Expanding the scope of their findings, the investigators examined a diverse array of cancers beyond lung cancer, validating TI-CH as an independent prognostic factor for reduced survival across multiple tumor types. Notably, TI-CH prevalence was elevated in malignancies historically linked with poor therapeutic responses, including pancreatic cancer and head and neck squamous cell carcinomas. This suggests that age-related clonal hematopoiesis may contribute to the treatment resistance observed in these cancer subsets, potentially through modulation of the tumor immune milieu.

This research marks a pivotal milestone in clarifying the interface between aging, clonal hematopoiesis, and cancer biology. While prior studies have focused on intrinsic tumor mutations and microenvironmental factors, the recognition that mutated blood-derived immune cells infiltrate and reprogram tumors introduces a paradigm shift. Understanding the precise molecular mechanisms by which CHIP-driven TI-CH influences cancer cell behavior and immune evasion could unlock new avenues for targeted therapies and intervention strategies.

Future research directions, as outlined by the team, will focus on establishing the causal relationships linking CHIP and aggressive cancer phenotypes, alongside elucidating the signaling pathways governing myeloid cell expansion and tumor infiltration. Such knowledge may pave the way for novel clinical approaches to modulate the impact of clonal hematopoiesis—either by targeting mutant myeloid populations or by reversing their tumor-promoting activities.

Oriol Pich, a postdoctoral scientist at the Crick’s Cancer Evolution and Genome Instability Laboratory and lead author of the study, stressed the clinical significance of these findings: “Our results reveal that blood cells carrying age-related mutations are not mere passive passengers but can actively infiltrate tumors, shaping cancer evolution and ultimately influencing patient outcomes.” The study highlights CHIP as a widespread, age-associated phenomenon common in cancer patients, underscoring the need to consider patient age and hematopoietic mutation status in personalized oncology.

Charlie Swanton, Deputy Clinical Director at the Francis Crick Institute and Chief Investigator for the TRACERx project, emphasized the transformative potential of linking two clonal proliferations—CHIP and solid tumor evolution. “This is a first-of-its-kind demonstration at scale that integrates age-related mosaicism in the hematopoietic system with cancer development. As we decode the mutations emerging during aging in bone marrow cells and their systemic effects, we open a new frontier in cancer prevention and treatment.”

Supported by Cancer Research UK and the National Institute of Health and Care Research UCLH Biomedical Research Centre, this landmark study published in the New England Journal of Medicine on April 23, 2025, charts unexplored territory in the intertwined pathologies of aging and cancer. It calls for the oncology community to incorporate the dynamics of clonal hematopoiesis into future clinical trials, risk assessment models, and therapeutic design, heralding a new era of precision medicine informed by the biology of aging.

Subject of Research: Animals
Article Title: Tumor-Infiltrating Clonal Hematopoiesis
News Publication Date: 23-Apr-2025
References: Pich, O. et al. (2025). Tumor-Infiltrating Clonal Hematopoiesis. New England Journal of Medicine.
Keywords: Lung cancer, Myeloid cells