TNBC is a subtype of breast cancer characterized by the absence of estrogen, progesterone, and HER2 receptors, which limits the effectiveness of many targeted therapies. The aggressive nature of TNBC is partly due to its early and rapid metastatic potential, complicating treatment and often leading to poorer prognoses. Until now, the role of the tumor microenvironment, particularly the impact of fat tissue in cancer progression, has remained elusive. The new study unveils how adipose tissue, far from being passive, actively facilitates tumor spread through specialized extracellular vesicles known as adipomes.

Adipomes are tiny, extracellular vesicles secreted by fat cells that serve as molecular messengers within the tumor microenvironment. What makes this discovery particularly compelling is the elucidation of how these adipomes initiate and promote the metastatic cascade in TNBC. By harnessing advanced purification techniques capable of isolating pure adipomes from intact tissues and bodily fluids, the team could detail the molecular crosstalk between adipose tissue and cancer cells. This pioneering methodology overcomes a significant technical hurdle that has historically hampered research progress, and it is currently the subject of a pending U.S. patent application filed by Hackensack Meridian Health.

The study shows that adipomes carry a distinct ‘lipid code’ that reprograms triple-negative breast cancer cells at the molecular level. This lipid signaling activates stress-response pathways, enhances protein synthesis, and upregulates mitochondrial signaling and translational machinery. These molecular alterations culminate in the formation of invadopodia—dynamic, actin-rich protrusions that penetrate the extracellular matrix. Invadopodia play a crucial role in cancer cell invasion, facilitating tissue degradation and enabling cancer cells to breach local tissue barriers and disseminate to distant organs.

Traditionally, tumor-adjacent adipocytes have been viewed as static reservoirs of energy that merely supply fatty acids to tumors. However, the current study challenges this dogma by demonstrating that adipocytes, through the secretion of adipomes, are active participants and orchestrators in the mammary tumor microenvironment. This dynamic interaction represents a previously unrecognized tumor-adipocyte signaling axis, crucial for the initiation and progression of metastasis in TNBC. Understanding this axis expands our knowledge of cancer biology and may pinpoint novel biomarkers or therapeutic targets.

The metastatic cascade in breast cancer has long been understood to initiate with cancer cells invading the stromal tissue, a process heavily facilitated by invadopodia. While the structural and functional properties of invadopodia are well characterized, the triggering mechanisms that lead to their formation have remained obscure. The current research specifically targets the pre-invadopodia phase, revealing that adipomes act as upstream influencers that ‘prime’ cancer cells for metastasis by setting off the molecular machinery necessary for invadopodia development.

Utilizing human clinical samples obtained from the Hackensack Meridian Health Network Biorepository and a variety of preclinical models, the researchers meticulously detailed every step of this metastatic progression. Their approach included isolating and profiling adipomes, assessing their lipid content, and analyzing the downstream signaling cascades activated in the cancer cells. The results illuminate how adipose tissue-derived vesicles extend beyond local interactions to influence distant metastatic niches, effectively hijacking normal cellular communication pathways to benefit tumor invasion and dissemination.

This profound insight into adipome-mediated signaling provides a plausible explanation for the notoriously high metastatic propensity of TNBC. By manipulating cellular stress responses and protein production, adipomes equip cancer cells with enhanced invasive capabilities, thus facilitating rapid disease progression. The identification of this signaling axis offers hope that new therapeutic strategies may emerge, aimed at disrupting adipome formation, release, or cancer cell reprogramming, potentially halting or reversing the progression of TNBC.

The implications of these findings reach beyond breast cancer alone. Dr. Nagajyothi’s laboratory has an extensive research portfolio that explores the role of adipose tissue in various diseases, including infectious diseases such as Chagas cardiomyopathy and pulmonary tuberculosis, as well as metabolic disorders like type 2 diabetes and lean diabetes. The current study underscores the multifaceted influence of adipose tissue in systemic disease processes, demonstrating its critical role in both infectious and non-infectious pathologies.

Looking forward, the research team envisions the development of novel diagnostic tools and interventions targeting the tumor-adipocyte communication mediated by adipomes. The ability to detect and potentially neutralize these vesicles could enable early intervention in metastatic TNBC, significantly improving patient outcomes. Moreover, the group’s proprietary isolation technique for adipomes, protected under a pending patent, stands poised to accelerate research and therapeutic development in this emerging field.

In summation, this pioneering work sets a new paradigm in cancer biology by firmly establishing adipomes as key regulators of metastatic behavior in triple-negative breast cancer. It powerfully illustrates how the tumor microenvironment, particularly adipose tissue, contributes actively to cancer progression. As researchers worldwide continue to unravel the complexities of tumor-host interactions, these insights pave the way for breakthrough therapeutic strategies aimed at one of the most challenging cancer subtypes known today.

Subject of Research: Human tissue samples

Article Title: Cancer-associated adipomes promote invadopodia formation and enhance metastatic potential in triple-negative breast cancer

News Publication Date: 3-Jun-2026

Web References:
https://doi.org/10.1038/s41523-026-00985-2

References:
Nagajyothi, J., Thangavel, H., Glazer, R., et al. (2026). Cancer-associated adipomes promote invadopodia formation and enhance metastatic potential in triple-negative breast cancer. npj Breast Cancer. https://doi.org/10.1038/s41523-026-00985-2

Image Credits: Hackensack Meridian Health

Keywords: Breast cancer, triple-negative breast cancer, metastasis, adipose tissue, adipomes, tumor microenvironment, invadopodia, extracellular vesicles, lipid signaling, cancer metastasis

Breast cancer continues to be a predominant cause of morbidity and mortality worldwide, ranking as the second most commonly diagnosed cancer and representing nearly a quarter of all cancer cases among women. Despite advances in diagnosis and treatment, the progression to lymph node metastasis remains a decisive prognostic factor negatively impacting survival. The precise molecular and cellular mechanisms orchestrating this metastatic cascade have remained elusive, limiting the development of targeted therapies capable of curbing metastatic spread effectively.

In a landmark effort, researchers integrated single-cell RNA sequencing data from 78 paired primary breast tumor and lymph node metastases samples, comprising an astonishing total of over 360,000 individual cells. This immense dataset enabled the identification of ten major cell types within the tumor microenvironment, including epithelial cancer cells, various immune subsets, and stromal components. Crucially, the spatial transcriptomics approach preserved the anatomical context of gene expression, facilitating the mapping of cellular interactions in situ and advancing comprehension of the metastatic niche architecture.

The study’s foremost revelation centers on early disseminated cancer cells (EDCs)—a distinctive epithelial subpopulation distinguished by enhanced metastatic and invasive traits. EDCs demonstrated pronounced metabolic reprogramming characterized by activated glycolytic pathways and hypoxia-responsive elements, which potentiate their survival and proliferation under adverse microenvironmental conditions. This metabolic plasticity enables EDCs to subvert immune defenses and thrive during dissemination to lymph nodes.

Beyond their intrinsic properties, EDCs engage in a sophisticated dialogue with the immune milieu, primarily orchestrated by M2-polarized macrophages and lymphocytes. These macrophages secrete cytokines such as CCL22 and CXCL12, fostering an immunosuppressive microenvironment that dampens anti-tumor immune responses and supports tumor cell evasion. This triadic crosstalk sets the stage for malignant transformation and sustains metastatic colonization, emphasizing the pivotal role of immune modulation in breast cancer progression.

Spatial transcriptomic analyses underscored that these interactions are not diffuse but rather concentrated within discrete regions at the invasive front of lymph node metastases. Such spatial compartmentalization accentuates the heterogeneity of the tumor microenvironment and underscores the relevance of microanatomical context in therapeutic targeting. The presence of these specialized niches reveals new potential vulnerabilities that can be exploited for more precise treatment modalities.

Leveraging these mechanistic insights, the investigators identified several tyrosine kinase inhibitors (TKIs), including pexidartinib hydrochloride and sunitinib malate, that selectively inhibit pathways crucial to M2 macrophage function, notably targeting the colony-stimulating factor 1 receptor (CSF1R). By impairing the immunosuppressive actions of these macrophages, such pharmacological agents demonstrate promising capabilities to halt or reverse lymph node metastasis, heralding a new class of adjunctive therapies in breast cancer management.

Both pexidartinib and sunitinib have established safety profiles in other oncologic contexts, bolstering the translational potential of repurposing these drugs against breast cancer metastasis. This promising overlap between existing therapeutics and newly discovered molecular targets accelerates the potential for clinical application, circumventing the lengthy traditional drug development pipeline.

Despite these advances, further research is imperative to dissect the metabolic vulnerabilities intrinsic to EDCs and to integrate comprehensive clinical datasets that validate these findings in patient populations. A systems biology approach combining metabolic profiling with immune landscapes will be crucial for developing synergistic intervention strategies that can effectively disrupt metastatic progression.

This study exemplifies the transformative power of single-cell and spatial multi-omics technologies to decode the complexity of tumor ecosystems in unprecedented detail. By unveiling the cellular heterogeneity and metabolic reprogramming events that underpin lymph node metastasis, the research charts a transformative course toward precision oncology, enabling the design of therapies tailored to the spatiotemporal dynamics of metastatic breast cancer.

Looking forward, the integration of such multi-dimensional datasets into clinical decision-making has the potential to redefine therapeutic regimens, enhance prognostic capabilities, and ultimately improve outcomes for breast cancer patients afflicted with metastatic disease. The study represents a milestone in understanding how cancer cells manipulate their environment and evade immune surveillance, highlighting new avenues for intervention that leverage metabolic and immune crosstalk.

As breast cancer continues to pose a significant global health challenge, innovations that decode tumor microenvironments at such granular levels are poised to shift paradigms in cancer treatment. This work not only deepens fundamental biological understanding but also accelerates the translation of genomics-driven discoveries into actionable clinical therapies designed to thwart metastasis at its earliest and most vulnerable stages.

The American Journal of Pathology’s publication of this integrative study underscores the critical role of advanced imaging and transcriptomic modalities in cancer research. By illuminating the cellular choreography of metastasis through novel lens, this research paves the way for more effective, personalized, and targeted interventions aimed at improving survival and quality of life for millions worldwide affected by breast cancer.

Subject of Research: Cells

Article Title: Deciphering the Cellular and Metabolic Landscape of Lymph Node Metastasis in Breast Cancer Using Single-Cell and Spatial Multi-Omics

News Publication Date: March 2, 2026

Web References:
https://doi.org/10.1016/j.ajpath.2026.01.002

References:
Zhu et al., The American Journal of Pathology, 2026. DOI: 10.1016/j.ajpath.2026.01.002

Image Credits: The American Journal of Pathology / Zhu et al.

Keywords: Breast cancer, lymph node metastasis, early disseminated cancer cells, tumor microenvironment, single-cell RNA sequencing, spatial transcriptomics, metabolic reprogramming, M2 macrophages, immunosuppression, tyrosine kinase inhibitors, precision oncology, metabolic-immune crosstalk

Adenoid cystic carcinoma (ACC) poses a significant clinical challenge due to its proclivity for distant metastases, particularly to the lungs. Until now, the precise pathways through which ACC cells metastasize and thrive in secondary sites have remained elusive. The team, led by Chen, Cw., Zhang, Sr., Yan, Ym., and collaborators, embarked on a comprehensive investigation to delineate how tumor-derived exosomal components influence the lung microenvironment to favor metastatic colonization.

Exosomes are nano-sized vesicles secreted by cells, functioning as intercellular messengers carrying various bioactive molecules including proteins, lipids, and RNAs. In cancer, exosomes can modify the distant tissue microenvironment, a concept known as pre-metastatic niche formation, effectively preparing ‘soil’ for disseminated tumor ‘seeds’. Focusing on ACC, the researchers identified S100A9 as a highly expressed protein in tumor-derived exosomes. This finding was significant because S100A9 has been implicated in inflammation and tumor progression in other cancers but had not been linked to ACC metastasis previously.

The researchers meticulously isolated exosomes from ACC cell lines and patient plasma, confirming elevated exosomal S100A9 levels compared to controls. Using state-of-the-art proteomic analysis, they established S100A9 as a dominant exosomal factor involved in intercellular communication. Functional assays revealed that these S100A9-rich exosomes had a pronounced effect on the behavior of stromal cells within the lung microenvironment, particularly cancer-associated fibroblasts (CAFs).

CAFs are a major component of the tumor stroma, known to support tumor growth, invasion, and immune evasion. The team demonstrated that exosomal S100A9 activates CAFs, inducing their transformation into a pro-metastatic phenotype. These activated fibroblasts, in turn, secrete extracellular matrix components and growth factors that create a nurturing scaffold, facilitating tumor cell survival and expansion within the lung tissue.

This interplay was shown to be critical for ACC lung metastasis using in vivo models. Mice injected with S100A9-enriched exosomes exhibited a significant increase in lung metastatic burden compared to those receiving exosomes depleted of S100A9. Importantly, pharmacologic inhibition or genetic knockdown of S100A9 abrogated the activation of CAFs and markedly suppressed metastatic colonization, highlighting its therapeutic potential.

From a molecular standpoint, the researchers identified signaling pathways downstream of S100A9 engagement with receptor complexes on fibroblasts. Activation of the NF-κB pathway was noted, which is a central regulator of inflammatory responses and fibroblast activation. This not only supports a pro-inflammatory microenvironment conducive to metastasis but also aligns with the well-established role of NF-κB in cancer progression and stromal remodeling.

The study further delved into clinical correlations, analyzing patient samples to validate the translational relevance of their findings. Elevated circulating exosomal S100A9 levels were associated with worse clinical outcomes and increased incidence of lung metastases in ACC patients. These data underscore the potential for S100A9 to serve as both a biomarker of metastatic risk and a candidate for targeted therapy.

Beyond basic science, the implications of this work are profound. Current treatment options for metastatic ACC are limited and often ineffective, with lung metastasis significantly reducing survival. Targeting exosomal S100A9 or its downstream signaling pathways could offer a novel strategy to disrupt the metastatic cascade at the interface between tumor and stroma, potentially improving patient prognosis.

Moreover, this research enriches our understanding of the tumor microenvironment as an active player in cancer biology, rather than a passive backdrop. The activation of CAFs by tumor-derived factors exemplifies the dynamic reciprocity that molds metastatic niches, emphasizing the need for therapies that address both cancer cells and their supporting stroma.

The use of cutting-edge exosome isolation techniques combined with proteomic profiling and in vivo validation provides a robust framework for further exploration. Future studies may investigate pharmacologic agents able to inhibit S100A9 secretion, block exosome uptake by fibroblasts, or disrupt downstream signaling cascades. Furthermore, the role of exosomal S100A9 in other cancer types and metastatic sites warrants examination to assess the broader applicability of these findings.

This pioneering work not only deciphers an intricate molecular dialogue but also holds promise for translational advances. Precision medicine approaches tailored to intercept exosomal communication may transform the management paradigm of ACC and metastatic cancers at large.

In conclusion, the study by Chen and colleagues marks a seminal advance in our comprehension of ACC metastasis. By spotlighting exosomal S100A9 as a principal mediator of lung colonization through CAF activation, they reveal a molecular vulnerability ripe for therapeutic exploitation. As research progresses, targeting the tumor microenvironment could decisively tilt the balance against metastatic cancer, heralding a new era of metastasis-directed cancer therapy.

Subject of Research: The role of exosomal S100A9 in promoting lung metastasis of adenoid cystic carcinoma via activation of cancer-associated fibroblasts.

Article Title: Exosomal S100A9 promotes lung metastasis of adenoid cystic carcinoma via activating cancer-associated fibroblasts.

Article References:
Chen, Cw., Zhang, Sr., Yan, Ym. et al. Exosomal S100A9 promotes lung metastasis of adenoid cystic carcinoma via activating cancer-associated fibroblasts. Cell Death Discov. (2026). https://doi.org/10.1038/s41420-026-02991-6

Image Credits: AI Generated

DOI: https://doi.org/10.1038/s41420-026-02991-6