Exosomes are lipid bilayer-encapsulated vesicles ranging typically from 30 to 150 nanometers in diameter. Tumor cells exploit exosomes to transfer a complex cargo that includes microRNAs (miRNAs), long noncoding RNAs (lncRNAs), circular RNAs (circRNAs), proteins, and lipids, effectively manipulating recipient cells in the microenvironment. This cargo reprograms cellular behavior by modulating critical signaling pathways such as PI3K/AKT, MAPK/ERK, Wnt/β-catenin, and NF-κB, all of which are well known for their roles in cell proliferation, survival, migration, and drug resistance. The review meticulously details how TDEs potentiate oncogenic signaling networks that facilitate tumor growth and metastasis.

Beyond their direct influence on tumor cells, TDEs substantially remodel the immune landscape of the TME. They achieve this through delivering immunoinhibitory molecules such as programmed death-ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), which suppress the activity of cytotoxic T cells and enable immune evasion. Additionally, TDEs promote the differentiation and recruitment of immunosuppressive populations including M2-polarized macrophages and regulatory T (Treg) cells, fostering an immunosuppressive niche that protects tumor cells from immune attack. This reciprocal modulation highlights the sophisticated crosstalk facilitated by exosomes, allowing tumors to sculpt an environment conducive to their survival and metastasis.

Conversely, the review illuminates the emerging therapeutic potential of exosomes derived from immune cells or engineered vesicles. Such exosomes can deliver antitumor cytokines, tumor-associated antigenic peptides, or RNA therapeutics designed to reactivate effector immune cells or reverse immunosuppression, thereby restoring antitumor immunity. This bifunctional nature—where exosomes function both as perpetrators of immune escape and as vehicles for immune restoration—positions them at a unique intersection for innovative therapeutic strategies, including combined immunotherapies and precision medicine approaches.

Another compelling aspect elucidated in the review is the utility of exosomes as liquid biopsy biomarkers. Because the molecular content of exosomes mirrors the heterogeneity and dynamic changes within tumors, profiling exosomal RNA and protein constituents offers a noninvasive window into tumor staging, mutation status, and therapeutic responsiveness. Such liquid biopsy approaches may revolutionize cancer diagnostics by enabling real-time monitoring of disease progression and early identification of treatment resistance, potentially allowing clinicians to tailor interventions with unprecedented precision.

Mechanistically, the biogenesis and release of exosomes involve the inward budding of the endosomal membrane to form multivesicular bodies, which subsequently fuse with the plasma membrane to release exosomes into the extracellular milieu. Tumor cells exhibit aberrant regulation of this process, often amplifying exosome production to disseminate oncogenic signals widely. The selective packaging of RNA species and proteins into exosomes is mediated by specific RNA-binding proteins and sorting machinery, underscoring the highly regulated and purposeful nature of exosome-mediated communication.

Of particular interest are the noncoding RNAs—miRNAs, lncRNAs, and circRNAs—enriched in TDEs, which serve as master regulators of gene expression in recipient cells. miRNAs, for instance, can inhibit tumor suppressor gene expression or activate oncogenes once internalized. lncRNAs and circRNAs add an additional layer of epigenetic and post-transcriptional control, influencing chromatin remodeling, mRNA stability, and microRNA sponging. The review catalogs several oncogenic noncoding RNAs identified in TDEs, implicating them in promoting angiogenesis, enhancing invasiveness, and modulating chemoresistance.

The signaling pathways activated by TDE cargo are canonical nodes within cancer biology: activation of the PI3K/AKT pathway enhances survival signaling and metabolic reprogramming; MAPK/ERK cascades regulate proliferation and differentiation; Wnt/β-catenin signaling controls stemness and epithelial-mesenchymal transition (EMT); and NF-κB pathway activation fosters inflammation and resistance to apoptosis. The convergence of multiple pathways modulated by exosomal cargos reveals a network complexity that underscores the challenge of targeting these processes therapeutically but also identifies numerous potential molecular targets.

Intriguingly, the immunomodulatory roles of exosomes present both opportunities and challenges in cancer immunotherapy. By transferring immune checkpoint molecules like PD-L1, TDEs shield tumors from immune surveillance. However, exosome-based delivery systems have shown promise in enhancing immune responses—engineered exosomes loaded with tumor antigens or immunostimulatory molecules can act as vaccines, stimulating dendritic cells and cytotoxic T lymphocytes. The review forecasts that integrating exosome engineering with checkpoint blockade or adoptive cell therapies could synergize to overcome resistance and improve patient outcomes.

The authors also explore the future potential of manipulating exosome pathways in therapeutic development. Strategies may include inhibiting exosome biogenesis or release to block pro-tumorigenic signaling, engineering exosomes as delivery vehicles for gene therapies or drugs, and designing exosome-based diagnostics and prognostic tools. Such approaches envision exosomes not simply as biomarkers but as active agents in precision oncology, capable of altering tumor behavior and immune responses in a controlled manner.

Moreover, the review emphasizes the importance of understanding the heterogeneity of exosomes, as vesicles differ widely depending on their cellular origin, molecular cargo, and biophysical properties. Advances in high-throughput sequencing, proteomics, and imaging technologies are critical for unraveling this complexity, enabling the identification of exosome subpopulations with distinct functional profiles that may have differential impacts on tumor progression or therapeutic response.

As research accelerates, the clinical translation of exosome-based approaches faces hurdles such as standardized isolation techniques, scalable manufacturing, and regulatory approval pathways. Nonetheless, the review maintains an optimistic outlook, citing numerous preclinical and early clinical studies that validate the significance of exosome biology in oncology. The dual role of tumor-derived exosomes—as both villains unleashing malignant phenotypes and as potential allies delivering therapeutic payloads—captures the duality inherent in cancer’s biological complexity.

In summary, exosomes stand at the forefront of contemporary cancer research, embodying a multifaceted paradigm that intertwines tumor biology and immune regulation. This review serves as a compelling synthesis of the state-of-the-art, weaving molecular insights with clinical implications and envisaging a future where exosome-based diagnostics and therapeutics reshape the oncology landscape. By decoding the language of these diminutive vesicles, scientists are poised to unlock novel avenues for combating one of humanity’s most formidable diseases.

Subject of Research: Tumor-derived exosomes and their dual roles in cancer progression and immune modulation.

Article Title: Dual Roles of Tumor-Derived Exosomes in Cancer and Immunity

Web References:
http://dx.doi.org/10.1002/mdr2.70022

Image Credits: The authors.

Keywords: Cancer, Tumor microenvironment, Tumor-derived exosomes, Noncoding RNA, Immune modulation, Liquid biopsy, Signal transduction, Immunotherapy, Exosome engineering

Radiation-induced mucositis is a frequent complication in patients undergoing radiotherapy, especially those treated for head, neck, and pelvic cancers. This condition not only compromises patient quality of life through severe pain and ulceration but also limits the dose of radiation that can be safely administered, thereby hampering therapeutic outcomes. Despite considerable investigation into pharmacological and biologic agents, effective preventive measures have remained elusive, largely due to the complex interplay of molecular and cellular events triggered by radiation exposure.

The study, published recently in Nature Communications, introduces a novel class of functionalized organic nanomaterials engineered to interact specifically with small extracellular vesicles (sEVs) and reactive oxygen species (ROS), both of which play pivotal roles in the pathophysiology of mucositis. These sEVs, which include exosomes and microvesicles, are tiny membrane-bound carriers released by cells undergoing stress or injury, conveying inflammatory signals that propagate tissue damage. Meanwhile, ROS are chemically reactive molecules containing oxygen that cause oxidative stress, DNA damage, and trigger apoptosis in mucosal cells following irradiation.

The researchers designed ultrathin organic sheets at the nanoscale, constructed from biocompatible polymeric materials tailored to have high surface-area-to-volume ratios. This structural feature maximizes their capacity to adsorb and neutralize sEVs and ROS before these pathogenic agents reach and harm the mucosal epithelium. By modulating key surface chemistries and optimizing the sheet’s porosity, the team achieved selective affinity toward these harmful targets, effectively transforming the organic nanostructures into molecular ‘sponges’ that can locally reduce inflammatory cascades.

Preclinical tests in animal models exposed to clinically relevant doses of radiation demonstrated that the application of these nanostructured sheets dramatically reduced the onset and severity of mucositis. Histological analysis revealed preserved epithelial integrity, reduced infiltration of inflammatory cells, and diminished ROS-induced oxidative markers in treated tissues compared to controls. Behaviorally, animals exhibited less pain-associated discomfort, correlating with these molecular and cellular findings.

Breaking down the mechanistic interactions, the sheets’ active surfaces bind to membrane proteins and lipid components of sEVs, sequestering them away from mucosal cells and preventing their signaling functions. Concurrently, the materials scavenge free radicals and suppress the cascade of oxidative damage. This synergistic dual-action mechanism interrupts the amplification loops that sustain and exacerbate mucosal injury during radiation therapy.

Beyond the protective role during radiotherapy, the researchers speculate that this technology could have wider applications in other inflammatory disorders where extracellular vesicles and oxidative stress are implicated. Conditions such as inflammatory bowel disease, chronic wounds, and even neuroinflammation might benefit from similar approaches to modulate pathogenic signaling in affected tissues.

From a clinical translation perspective, the nanostructured organic sheets offer practical advantages. Their fabrication relies on scalable and cost-effective polymer chemistry processes, and the materials exhibit favorable biocompatibility profiles with minimal toxicity. Additionally, due to their sheet-like morphology, they can be conveniently applied as topical barriers on mucosal surfaces or incorporated into dressings, making them adaptable to various treatment settings.

The innovation also addresses existing limitations of antioxidant therapies, which often suffer from poor targeting specificity and rapid degradation in vivo. By immobilizing the scavengers within a nanostructured matrix, the therapeutic efficacy is prolonged, and unwanted systemic effects are minimized. This precision in action represents an essential step towards personalized supportive care in oncology.

Furthermore, the ability to trap sEVs opens up new avenues for modulating intercellular communication in the tumor microenvironment. Since sEVs can transport oncogenic molecules and modulate immune responses, controlling their activity locally could impact tumor progression and responses to therapy beyond mucositis management. This raises intriguing possibilities for combining the nanostructured sheets with immunotherapies or chemotherapeutic regimens.

The researchers employed advanced characterization techniques, including electron microscopy, spectroscopy, and bioassays, to verify the physical interactions and biological outcomes. Importantly, the nanomaterials demonstrated stability under physiological conditions and retained their functional capabilities for extended durations, supporting their use in chronic treatment scenarios.

In the broader context of radiation medicine, the advent of these nanostructured organic sheets exemplifies the merging of nanotechnology and molecular biology toward addressing unmet medical challenges. By harnessing the unique physicochemical properties at the nanoscale, the researchers have engineered a novel solution that intervenes dynamically in pathological molecular networks activated by radiation.

As the team progresses towards clinical trials, key focal points will include optimizing delivery methods, confirming long-term safety, and evaluating efficacy across varied radiation protocols and patient populations. Collaboration with clinicians and regulatory agencies will be vital to navigate the path from bench to bedside efficiently.

This pioneering work not only introduces a potent therapeutic tool but also deepens our understanding of the contributions of extracellular vesicles and oxidative stress in radiation-induced tissue injury. By illuminating these intricate mechanisms and offering a strategy to modulate them, it opens a promising frontier in radioprotection and inflammation management.

Ultimately, the development of these nanostructured organic sheets underscores the potential of interdisciplinary research, combining materials science, molecular biology, and clinical medicine to generate impactful solutions that enhance patient outcomes and quality of life in cancer therapy and beyond.

Subject of Research: Radiation-induced mucositis prevention through nanostructured organic materials targeting extracellular vesicles and reactive oxygen species.

Article Title: Nanostructured organic sheets sequestering small extracellular vesicles and reactive species to protect against radiation-induced mucositis.

Article References:
Zhu, Y., Xu, C., Li, Z. et al. Nanostructured organic sheets sequestering small extracellular vesicles and reactive species to protect against radiation-induced mucositis. Nat Commun 16, 6120 (2025). https://doi.org/10.1038/s41467-025-61236-9

Image Credits: AI Generated