Exosomal miRNA as a biomarker for diagnosis and prognosis, and a new target for regulating treatment resistance in DLBCL: a research progress narrative review

Introduction

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of aggressive non-Hodgkin lymphoma (NHL) worldwide, accounting for approximately 30–40% of all NHL cases. Its incidence demonstrates a consistent global distribution, affecting individuals across diverse geographic regions and ethnic populations. The high prevalence of DLBCL underscores its significant public health burden and the urgent need for effective therapeutic strategies universally applicable across different healthcare settings, accounting for a significant proportion of NHL cases and presenting considerable clinical challenges due to its biological diversity and variable treatment outcomes (1,2). It exhibits high malignancy and heterogeneity, with a subset of cases demonstrating intrinsic or acquired resistance to the standard first-line R-CHOP immunochemotherapy regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). This resistance often leads to incomplete remission, early relapse, or refractory disease, contributing to elevated post-treatment recurrence rates and a persistently poor overall prognosis, particularly in high-risk subgroups (2-5). Despite the breakthrough success of polatuzumab vedotin (Pola)-an antibody-drug conjugate (ADC) targeting CD79b-in improving outcomes for both frontline and relapsed/refractory (R/R) DLBCL, intrinsic and acquired resistance inevitably limits its long-term efficacy (2). Consequently, there is an urgent and unmet clinical need to elucidate the underlying molecular mechanisms driving therapy resistance and to identify novel targets that can improve long-term survival.

Exosomes are 30–200 nm extracellular vesicles (EVs) that mediate intercellular communication in the tumor microenvironment (TME) (6). They are secreted by various cells, including tumor cells, and carry bioactive molecules such as proteins, lipids, and nucleic acids; among these, miRNAs are functionally critical (7). MiRNA loading into exosomes is regulated by RNA-binding proteins (RBPs) and lipid metabolism (8). EXOmotifs and CELLmotifs direct miRNA packaging or retention (8). Key RBPs include SUMOylated hnRNPA2B1 (binds EXOmotifs) (9), YBX1, and MVP (10). Lipid metabolism via nSMase2/ceramide promotes MVB invagination to encapsulate miRNAs (10). Secreted exosomal miRNAs are taken up by recipient cells, silencing target genes and affecting TME, immunity, and drug resistance (11). Inside recipient cells, exosomal miRNAs are processed to mature single-stranded forms and loaded into AGO2/RISC, regulating proliferation, apoptosis, immune evasion, and drug sensitivity (10,12). Exosomal miRNAs have been linked to lymphoma drug resistance, and targeting them to reverse resistance is a growing research focus (13). For instance, in rituximab-resistant DLBCL, exosomal miRNAs are promising diagnostic biomarkers and therapeutic targets, as their dysregulation correlates with disease progression and treatment failure. However, the precise regulatory network underlying miRNA-mediated drug resistance remains incompletely understood and requires further investigation.

This article aims to comprehensively review recent advances in the study of exosomal miRNAs in DLBCL. Specifically, it evaluates their emerging roles in improving diagnosis and molecular subtyping, assessing prognosis, and monitoring therapeutic response. Furthermore, the review delves into the mechanisms by which exosomal miRNAs contribute to drug resistance, focusing on pathways involving autophagy, drug efflux, and immune modulation. Finally, we discuss potential translational applications and future research directions aimed at harnessing exosomal miRNA biology to develop more effective strategies for overcoming treatment resistance and improving patient outcomes in DLBCL. We present this article in accordance with the Narrative Review reporting checklist (available at https://tcr.amegroups.com/article/view/10.21037/tcr-2026-0532/rc).

Methods

A literature search was conducted in PubMed and Web of Science databases using the keywords “exosome” OR “miRNA” OR “exosomal miRNAs” AND “diffuse large B‑cell lymphoma” OR “DLBCL” OR “biomarker” OR “drug resistance” OR “tumor micro-environment” OR “TME” OR “lymphoma” OR “cell death”. The secondary references cited in articles obtained from the PubMed and Web of Science search were also retrieved. The evidence of exosomal miRNAs in DLBCL analyzed in this review is not limited to DLBCL, NOS, but also includes other types of DLBCL (for example, EBV-associated lymphoma). In addition, this review also includes high-grade B-cell lymphomas (double-hit, carrying MYC and BCL2 translocations). The methodology of the search is summarized in Table 1.

Biogenesis of exosomal miRNA in DLBCL

The discovery of exosomes dates back to 1983 when Pan and Johnstone, during observations of sheep reticulocyte maturation, identified small membrane vesicles actively released into the extracellular environment. Notably, these vesicles specifically participated in the externalization of transferrin receptors, suggesting they were not mere cellular debris but functional organelles (14). Subsequent studies using differential centrifugation and electron microscopy further characterized their physical and biochemical properties. Accumulating evidence indicated that these vesicles carried specific molecular cargo and were involved in intercellular communication. In 1989, Johnstone and colleagues formally named them “exosomes” to distinguish them from other EVs (e.g., microvesicles and apoptotic bodies) (15), marking their recognition as key mediators of cellular crosstalk.

As stated in the previous “Introduction” section, exosome biogenesis is a highly ordered intracellular process. They originate from early endosomes formed by the invagination of the plasma membrane. These endosomes mature into multivesicular bodies (MVBs), where intraluminal vesicles (ILVs) are formed through ESCRT-dependent and ESCRT-independent pathways. Specific molecules, including proteins and nucleic acids, are sorted into ILVs. MVBs fuse with the plasma membrane, releasing ILVs as exosomes into the extracellular space (16). Exosomes are composed of a lipid bilayer membrane and various proteins. Importantly, exosomes carry various nucleic acids, including miRNA, constituting key functional cargo (17). Exosomes are secreted into bodily fluids and, after being taken up by recipient cells through endocytosis, membrane fusion, or receptor interactions, the miRNAs in exosomes can regulate gene expression by binding to target mRNAs, modulating cellular signaling networks, and thereby participating in various physiological and pathological processes, including cell differentiation, migration, immune activation, tissue repair, angiogenesis, tumor progression, and neurodegeneration (Figure 1).

Figure 1 The biogenesis, structure, and interaction mechanisms of exosomes with target cells. Exosomes originate from intracellular MVBs, which fuse with the plasma membrane to release exosomes (30–150 nm in diameter) into the extracellular space. These exosomes carry a variety of bioactive molecules, including transmembrane proteins (CD9, CD63, CD81, integrins, etc.), cytoskeletal proteins (actin), and nucleic acids (mRNA, miRNA, DNA, lncRNA). Once released, exosomes can interact with recipient cells through three primary mechanisms: endocytic uptake, ligand/receptor binding, or direct fusion with the plasma membrane to release their contents, thereby facilitating intercellular communication. MVBs, multivesicular bodies.

Research progress on exosomal miRNAs as novel biomarkers in the diagnosis and prognosis of DLBCL

DLBCL is a highly heterogeneous group of aggressive lymphomas with distinct biological behaviors (18,19). Among them, non-germinal center-derived DLBCL (non-GCB DLBCL) has a poor treatment response. Despite the establishment of a standard first-line regimen of rituximab combined with chemotherapy for DLBCL, a considerable number of relapsed/refractory cases still exist, and these cases often exhibit resistance to rituximab combined with chemotherapy (20). Therefore, the development of a new biomarker for the diagnosis and prognosis of DLBCL is of great significance.

Recent studies have found significant differences in the expression of certain exosomal miRNAs between DLBCL patient groups and healthy control groups. For example, Cao et al. found that exosomal miRNAs miR-379-5p, miR-135a-3p, miR-4476, miR-483-3p, and miR-451a exhibit significant differences in expression between DLBCL patients and healthy controls (21), suggesting that exosomal miRNAs are unique tumor biomarkers that can be used for the diagnosis of DLBCL. Moreover, exosomal miRNAs also aid in the identification of molecular subtypes of DLBCL, including: (I) activated B-cell-like (ABC) DLBCL subtype. Studies have found that the exosomal miRNA miR-17-92 cluster (including miR-17, miR-19a, etc.) and miR-155 selectively activates NF-κB pathway in activated B-cell-like DLBCL, promoting cell proliferation (22-24), suggesting that exosomal miRNAs are special tumor biomarkers in ABC-DLBCL. (II) EBV-associated DLBCL subtype. Akyüz et al. found that hsa-miR-181a, hsa-miR-181b, hsa-miR-183, hsa-miR-21, hsa-miR-155, hsa-miR-155*, hsa-miR-221, and hsa-miR-222 showed exclusive EBV-dependent up-regulated (25). Furthermore, Wu et al. have also revealed that the combined detection of exosomal miRNA miR-BART5-5p and LMP1 can enhance the diagnostic specificity of EBV-positive DLBCL (26). These above researches suggesting that exosomal miRNAs are special tumor biomarkers in EBV-associated DLBCL.

Exosomal miRNAs also play a role in the prognosis assessment of DLBCL. Preliminary findings include: (I) exosomal miRNAs miR-379-5p, miR-135a-3p, miR-4476, and miR-451a are differentially expressed in DLBCL patients and can be used for prognostic prediction (21). Among them, exosomal miRNA miR-451a is significantly associated with progression-free survival (PFS) and overall survival (OS) in DLBCL patients, and combining it with the International Prognostic Index (IPI) better predicts patient outcomes (21). (II) Exosomal miRNA miR-155 is highly expressed in aggressive DLBCL and can increase B-cell lymphoma cell proliferation by inhibiting FOXP3, exerting an anti-apoptotic effect, and is associated with shorter event-free survival (EFS) (20). (III) In DLBCL patients who achieve complete remission (CR) after treatment, exosomal miRNA miR-21 levels significantly decrease, whereas in patients who still progress (PD) after treatment, the levels continue to rise (27,28). (IV) High expression of exosomal miRNA miR-181a-5p can promote DLBCL tumor invasion by inhibiting GTSE1 and regulating the p53/NF-κB pathway, and is associated with poor DLBCL prognosis (29). (V) Up-regulated expression of exosomal miRNAs miR-23a, miR-125a, and miR-100 is associated with longer OS in DLBCL patients, while decreased expression of miR-143 and let-7a indicates poor prognosis (30). (VI) During chemotherapy, sustained high expression of exosomal miRNA miR-181a (>2-fold baseline) can predict DLBCL relapse risk within 12 months (HR =4.2) (29,31).

We listed the association between exosomal miRNAs and different subtypes of DLBCL in a table (Table 2) to better summarize the role of exosomal miRNAs in the diagnosis and prognosis assessment of different DLBCL subtypes. However, through the review of the literature mentioned above, we can also clearly see that there are quite a number of exosomal miRNAs showing associations with DLBCL diagnosis and prognosis, and they are rather diverse. No so-called “hot” or “common” exosomal miRNAs have been found that can assist in diagnosis or correspond to a specific prognosis. This means that even though we currently know that exosomal miRNAs can aid in the diagnosis and prognosis assessment of DLBCL, it is still difficult in the real world to construct a DLBCL prognosis model incorporating exosomal miRNAs through targeted sequencing. Moreover, the specimens used in different studies, the handling of these specimens, and the RNA sequencing technologies employed vary as well, which also affects our ability to identify “marker genes”. In the future, we should first establish internationally standardized exosomal miRNA sequencing techniques and, through big data studies, identify exosomal miRNAs that are highly associated with diagnosis and prognosis, frequently occur, and are considered hot topics, and perform in vivo and in vitro functional studies for verification. Only then can exosomal miRNAs potentially be incorporated into DLBCL diagnosis and prognosis assessment models.

Research progress on the mechanisms of exosomal miRNA in regulating therapeutic resistance in DLBCL

As mentioned earlier, preliminary studies have established that exosomal miRNAs serve as novel diagnostic and prognostic biomarkers for DLBCL. This clinical relevance arises, in part, from the discovery that aberrant expression of exosomal miRNAs can modulate DLBCL treatment responses through specific mechanistic pathways, thereby influencing tumor resistance and disease progression (20,27,28). Therefore, following the confirmation of their biomarker potential, research focus has shifted toward elucidating the regulatory roles of exosomal miRNAs in cellular resistance and death mechanisms. This research direction has substantially elevated the medical significance of exosomal miRNAs, positioning them as promising candidates for developing novel strategies to reverse drug resistance.

Currently, several exosomal miRNAs associated with “chemo- (CHOP or other chemo-therapies)” or “rituximab(R) combined with chemo-(R-CHOP or other R-chemo-therapies) “ resistance have been identified in DLBCL: (I) In DLBCL patients resistant to rituximab combined with CHOP chemotherapy, exosomal miR-22 is significantly upregulated. Functional studies demonstrate that overexpression of miR-22 reduces tumor cell proliferation, suggesting that miR-22 regulates DLBCL progression by modulating cell cycle dynamics (32). (II) In chemotherapy-resistant DLBCL patients, the expression levels of exosomal miR-99a-5p and miR-125b-5p are markedly higher compared to chemotherapy-sensitive individuals. Subsequent bioinformatic analyses of multi drug-resistant DLBCL cells have implicated several biological signaling pathways, including AMPK, TGF-β, mTOR, and p53 signaling cascades (33), suggesting that modulating the expression of these exosomal miRNAs may represent a viable approach to alter cellular resistance phenotypes. (III) Comparative study from Jabłońska et al. have revealed that, relative to healthy controls, five exosomal miRNAs are up-regulated while three are down-regulated in DLBCL patients. Notably, miR-130a and miR-125b were significantly elevated in the R-CHOP treatment-resistant group, and patients in this group exhibited a higher likelihood of recurrence, disease progression, and chemo-resistance. Conversely, patients with down-regulation of these two miRNAs were more likely to achieve complete remission following treatment and demonstrated enhanced therapeutic sensitivity (34). (IV) miRNA expression profiling of R-CHOP-treated DLBCL tumor tissues revealed that high expression of exosomal miRNA-363-3p significantly correlates with resistance to anthracycline-based chemotherapy. Knockdown of miRNA-363-3p resulted in reduced tumor cell proliferation, and subsequent mechanistic studies confirmed dual-specificity phosphatase 10 as a direct target of miRNA-363-3p (35). (V) Exosomal miR-155-5p derived from DLBCL patients can be internalized by natural killer (NK) cells, leading to impaired NK cell proliferation and cytotoxic activity, thereby contributing to immune evasion by DLBCL tumor cells, which lead to chemo-therapy resistance (36).

Although the correlation between exosomal miRNAs and therapy resistance in DLBCL is relatively well established, the precise underlying regulatory mechanisms remain incompletely characterized, rendering this a vibrant area of contemporary investigation. Previous studies have identified five primary mechanisms through which exosomal miRNAs modulate recipient cell functions to reverse therapy resistance in DLBCL: (I) signaling pathway regulation: Exosomal miR-21 directly inhibits FOXO1 and its transcriptional target Bim by binding to the 3’-UTR of FOXO1, while also indirectly suppressing FOXO1 through activation of the PI3K/AKT pathway in DLBCL (37). Exosomal CA1 promotes chemotherapy resistance by activating NF-κB and STAT3 signaling pathways (38). Conversely, over-expression of exosomal miR-107 inhibits tumor proliferation and induces apoptosis, potentially reversing drug resistance (38,39). Furthermore, exosomal ENO2 induces M2-type macrophage polarization through the glycolysis-dependent GSK3β/β-catenin/c-Myc signaling axis, thereby promoting DLBCL proliferation, migration, and invasion (40). (II) Post-transcriptional regulation: DLBCL-derived exosomal miRNAs can regulate gene expression in recipient cells by binding to the 3’ untranslated region (3’UTR) of target mRNAs, resulting in translational inhibition or mRNA degradation (19). (III) TME modulation: Studies spanning both solid tumors and hematologic malignancies have revealed that interactions between exosomal miRNAs and lysosomal membrane proteins can influence cellular metabolic programming, thereby promoting the growth of various tumor cells (41). Specifically within the DLBCL context, exosomal miRNAs promote M2-type macrophage polarization, enhancing immune evasion (42), and activate dendritic cells (DCs) by carrying tumor-associated antigens (TAAs), thereby exerting immunosuppressive effects (37). (IV) Drug metabolism regulation: Investigations in B-cell lymphoma models indicate that exosomal miRNAs may participate in the efflux of adriamycin from cells, consequently influencing chemotherapy resistance (43). (V) Autophagy and apoptosis regulation: C-MYC-dependent exosomal miR-7-5p inhibits autophagy and apoptosis by targeting AMBRA1, a key autophagy regulatory protein, thereby promoting DLBCL chemo-resistance (44). Mechanistically, overexpression of miR-7-5p suppresses AMBRA1 expression, leading to reduced autophagy and impaired apoptosis in DLBCL cells, ultimately conferring treatment resistance (45). Additionally, down-regulation of exosomal hsa-miR-548d-3p significantly correlates with overexpression of exosomal HOXA9 mRNA, which drives DLBCL resistance and disease progression through up-regulation of the anti-apoptotic protein BCL2, activation of the JAK/STAT signaling pathway, and disruption of p53 pathway function (46). Notably, therapeutic targeting of miR-130b can regulate tumor cell autophagy through OX40/OX40L-mediated interactions with Th17 cells, counteracting DLBCL progression (47).

We summarize the mechanisms by which exosomal miRNAs regulate treatment resistance in DLBCL schematically in Figure 2. Based on this comprehensive literature review, we are confident that exosomal miRNAs represent an ideal direction for developing novel therapeutic targets and mechanistic interventions for refractory and relapsed DLBCL. However, it must be acknowledged that the majority of current research remains at the cellular level; further validation in animal models and human specimens represents an essential direction for future scientific inquiry. In the following sections, we continue to review and synthesize the current research landscape, existing challenges, and future directions for exosomal miRNAs as regulatory targets for reversing DLBCL drug resistance.

Figure 2 Exosome miRNA regulation of DLBCL therapy resistance. Exosomal miRNAs participate in the regulation of therapy resistance through five major pathways: 1. signaling pathway regulation; 2. post-transcriptional regulation; 3. tumor microenvironment remodeling; 4. drug metabolism regulation; 5. autophagy and apoptosis regulation. DLBCL, diffuse large B-cell lymphoma.

Research challenges and future prospects

Current translational studies using exosomal miRNAs to control drug resistance in DLBCL

miRNA-based therapeutic strategies

Two complementary approaches for miRNA therapy have been experimentally validated: miRNA inhibitors targeting oncogenic miRNAs, and miRNA mimics restoring tumor-suppressive miRNAs.

miRNA inhibitors. Suppressing oncogenic exosomal miRNAs exerts therapeutic effects. Exosomal miR-155 inhibitors reduce tumor growth in lymphoma mouse models (48,49). Clinical evidence from a relapsed DLBCL patient showed significant lymph node shrinkage after five cycles of inhibitor monotherapy (49). Transfection of DLBCL cells with miR-155a inhibitors decreased cell survival and reduced HCV-RNA viral load (50). Exosomal miR-21 inhibitors enhance CHOP or adriamycin/rituximab cytotoxicity in DLBCL cells by modulating PTEN/PI3K/AKT signaling (47,51). Inhibition of miR-125b-5p improves rituximab efficacy via TNFAIP3 targeting (52), and targeting miR-130b regulates autophagy through OX40/OX40L-Th17 interactions (47).

miRNA mimics. Restoring downregulated tumor-suppressor miRNAs with mimics reverses resistance. miR-199a-3p and miR-497 mimics increased drug sensitivity in DLBCL cells, enhancing apoptosis when combined with epirubicin or vincristine (53). miR-124-3p mimics delivered via MSC exosomes inhibited DLBCL proliferation and promoted apoptosis via NFATc1/cMYC downregulation (54). Exosomal miR-107 agomir reduced proliferation and migration while promoting apoptosis by targeting YWHAH (55). miR-665 mimics suppressed DLBCL invasion and induced apoptosis via LASP1 and MYC targeting (56). A systematic review confirmed exosomal miRNAs as promising therapeutic tools and response predictors in DLBCL (57).

Challenges of using EV-derived miRNAs

EV-miRNAs hold promise as liquid biopsy biomarkers and therapeutic vehicles (58), particularly in DLBCL (6). However, clinical translation faces biological, technical, and validation challenges.

Quantitative and stoichiometric challenges

Even abundant miRNAs average <1 copy per EV (~0.008 copies/vesicle), challenging the “one vesicle, one message” paradigm (58,59). This low occupancy forces reconsideration of EV-miRNA function (10,58). Two models exist: the “ensemble model” (cumulative reprogramming by many low-copy EVs) and the “rarity model” (functional effects driven by high-load vesicles or non-vesicular Argonaute-bound complexes) (60,61). Absolute quantification methods (digital PCR, UMI-aware small RNA-seq) are needed rather than particle counts or relative quantification (58). Dosing strategies must integrate particles, protein content, and mechanistic miRNA copy numbers (58).

Technical biases, purity concerns, and standardization gaps

RNA isolation methods introduce variability (62). Circulating miRNAs associated with protein complexes (Argonaute) or lipoproteins confound EV-specific attribution(61). Rigorous validation requires protease/nuclease treatments, density gradient fractionation, and Ago2-depletion controls (58,63). In DLBCL research, three major bottlenecks persist: (I) lack of standardized miRNA extraction methods—ultracentrifugation vs. kits cause variable recovery (64); (II) superficial mechanistic studies—most focus on expression profiling without functional validation (65); (III) technical obstacles for translation—low target abundance, poor probe penetration, and time-consuming qPCR requiring exosome lysis and RNA extraction (66). Detection techniques need optimization in sensitivity, specificity, and standardization, plus multi-center validation (67).

Standardization and functional validation

MISEV2023 provides a framework for pre-analytical variables, separation characterization, and functional study design (6,68). Adherence remains inconsistent, especially for isolation methods and potency assays (54). Lack of universal reference genes hampers cross-study comparability; normalization strategies vary (spike-ins, total RNA, sample volume, particle number) (61,62). Establishing causality requires loss- and gain-of-function evidence with orthogonal readouts, avoiding confounding by co-isolated factors (54,60). Potency assays must link to critical quality attributes (miRNA copy numbers, identity markers) with analytical validation (54,58). Adherence to MISEV standards, absolute quantification, and rigorous validation are essential for clinical success (6,54,68).

Exosomal miRNAs as dynamic interactors with the epigenetic landscape in DLBCL: implications for precision medicine

DLBCL pathogenesis is driven by disrupted epigenetics-mutations in EZH2, KMT2D, CREBBP, TET2, aberrant DNA methylation, and dysregulated non-coding RNAs (69). These alterations drive immune evasion, oncogenic signaling, and resistance, moving beyond a purely genetic view (69). Exosomal miRNAs actively propagate epigenetic signals throughout the TME, influencing chromatin remodeling, DNA methylation, and post-transcriptional regulation of genes central to B-cell transformation and treatment response (44,70). This bidirectional interplay-epigenetic changes dictate exosomal miRNA cargo, which in turn modulates recipient cell epigenetics-creates a self-reinforcing network promoting progression and resistance (52). Targeting this crosstalk with epigenetic modulators and exosome-based strategies holds promise, but requires precision medicine integrating longitudinal, non-invasive exosomal miRNA monitoring with the patient’s unique epigenetic profile (71).

Exosomes and emerging drug resistance to novel therapeutic agents in DLBCL: insights into ADC and bispecific antibody escape

ADCs (polatuzumab vedotin, loncastuximab tesirine) and bispecific T-cell engagers have transformed DLBCL therapy, but resistance inevitably emerges. Exosomes are key mediators of this resistance.

ADCs: exosomes as antibody decoys. In Pola-resistant DLBCL lines, MDR1 overexpression or decreased Bim expression were identified (72). Pola-resistant cells remained sensitive to Pola+rituximab retreatment via enhanced CDC (72). CD30+ EVs from DLBCL cells bind brentuximab vedotin, conferring binding capacity to CD30-negative cells and acting as a decoy (73). This mechanism likely applies to other ADCs (CD79b- or CD19-targeting). For loncastuximab, resistant cells paradoxically show higher CD19 expression, suggesting complex adaptive responses beyond antigen loss (74).

Bispecific antibodies: exosomes as immune modulators. Regulatory T-cell phenotypes associate with bispecific antibody failure (75). Tumor-derived exosomes carrying immunosuppressive molecules (PD-L1, TGF-β) or target antigens (CD20, CD19) can blunt T-cell engagement or act as decoys.

Unified mechanism: exosomal antigen decoy. ABCA3 modulates exosome biogenesis in aggressive B-cell lymphoma; CD20+ exosomes bind anti-CD20 antibodies, consume complement, and protect target cells (76). CD20+ small EVs confer rituximab resistance, enhanced by TrkB activation (75).

In conclusion, exosomes drive resistance to ADCs and bispecific antibodies via: (I) decoy effects (antigen-positive exosomes sequester antibodies); (II) immune modulation (impairing T-cell function); (III) transfer of resistance-associated proteins (MDR1) and miRNAs. Future research should characterize exosomal cargo in patients on novel agents, identify predictive biomarkers, and target exosome biogenesis (e.g., ABCA3) to overcome resistance.

Conclusions

In summary, exosomal miRNAs can serve as biomarkers for the diagnosis and prognostic assessment of DLBCL and are associated with DLBCL treatment resistance. Currently, there has been significant progress in research on the mechanisms by which exosomal miRNAs regulate DLBCL resistance, with some mechanisms already validated. It is expected that through more in-depth in vivo and in vitro studies in the future, mature therapeutic targets can be developed.

Looking ahead, exosomal miRNAs, as new therapeutic targets to reverse DLBCL resistance, hold considerable development value and social benefits. As research in this field continues to deepen, the potential for drug development will increase. Developing exosome-based drugs or cell therapies for DLBCL treatment is of important positive significance for improving refractory and relapsed DLBCL cases with resistance. However, most current studies are still at the basic in vitro level. Future work will require sequencing and big data analysis to identify exosomal miRNAs that regulate resistance across multiple DLBCL subtypes. More in vivo studies are also needed to validate the mechanisms by which specific exosomal miRNAs regulate DLBCL resistance. Additionally, it is important to note that the mechanisms involved in chemotherapy resistance and resistance to biological therapies are not the same, so research should carefully distinguish which type of resistance each exosomal miRNA affects.

In conclusion, exosomal miRNAs represent a novel therapeutic strategy that requires comprehensive and in-depth research, is highly anticipated, and holds the potential to innovatively improve the treatment landscape of resistant DLBCL.

Acknowledgments

We gratefully acknowledge the linguistic support provided by Guangzhou Saiqing Biotechnology Co., Ltd. during the preparation of this manuscript. We also thank Professor Ye Lei and Professor Rosalind Ang from the Icahn School of Medicine at Mount Sinai for providing therapeutic guidance during the preparation of this manuscript.

Footnote

Reporting Checklist: The authors have completed the Narrative Review reporting checklist. Available at https://tcr.amegroups.com/article/view/10.21037/tcr-2026-0532/rc

Peer Review File: Available at https://tcr.amegroups.com/article/view/10.21037/tcr-2026-0532/prf

Funding: This work was supported by the Natural Science Foundation of Guangdong Province (Nos. 2022A1515012609 and 2022A1515012652), Guangzhou Science and Technology Plan (Nos. 2023A03J0530, 20241A010006, 20251A010010 and 20261A011006), People’s Livelihood Technology Project in Nansha District of Guangzhou (No. 2024MS008), and the Major Innovative Technology Project for the Integration of Traditional Chinese and Western Medicine in Guangzhou [Guangzhou Traditional Chinese Medicine (2023) No. 4]. The funders had no roles in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tcr.amegroups.com/article/view/10.21037/tcr-2026-0532/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Crombie JL, Armand P. Diffuse Large B-Cell Lymphoma and High-Grade B-Cell Lymphoma: Genetic Classification and Its Implications for Prognosis and Treatment. Surg Oncol Clin N Am 2020;29:115-25. [Crossref] [PubMed]
2. Xu X, Liu M, Wang Z. Beyond R-CHOP: The rise of antibody-drug conjugates in DLBCL. Blood Rev 2026; Epub ahead of print. [Crossref]
3. Li Y, Zhang Y, Zhu C, et al. Novel immunotherapeutic strategies for diffuse large B-cell lymphoma: a comprehensive review. Front Immunol 2026;17:1704254. [Crossref] [PubMed]
4. Kim SW, Asakura Y, Tajima K, et al. Retraction Note to: High-dose therapy and autologous stem cell transplantation for relapsed or high-risk diffuse large B-cell lymphoma: a nationwide survey. Int J Hematol 2020;112:907. [Crossref] [PubMed]
5. Eyre TA, Cwynarski K, d'Amore F, et al. Lymphomas: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up. Ann Oncol 2025;36:1263-84. [Crossref] [PubMed]
6. Welsh JA, Goberdhan DCI, O'Driscoll L, et al. Minimal information for studies of extracellular vesicles (MISEV2023): From basic to advanced approaches. J Extracell Vesicles 2024;13:e12404. [Crossref] [PubMed]
7. Ni YQ, Lin X, Zhan JK, et al. Roles and Functions of Exosomal Non-coding RNAs in Vascular Aging. Aging Dis 2020;11:164-78. [Crossref] [PubMed]
8. Corsi J, Semnani PS, Peroni D, et al. Small molecule inhibitors of hnRNPA2B1-RNA interactions reveal a predictable sorting of RNA subsets into extracellular vesicles. Nucleic Acids Res 2025;53:gkaf176. [Crossref] [PubMed]
9. Marocco F, Garbo S, Montaldo C, et al. Negative regulation of miRNA sorting into EVs is mediated by the capacity of RBP PCBP2 to impair the SYNCRIP-dependent miRNA loading. Elife 2025;14:RP105017. [Crossref] [PubMed]
10. Huang Z, Zhao X, Wen W, et al. Exosome miRNA sorting controlled by RNA-binding protein-motif interactions. Extracell Vesicles Circ Nucl Acids 2025;6:475-503. [Crossref] [PubMed]
11. Komuro H, Aminova S, Lauro K, et al. Advances of engineered extracellular vesicles-based therapeutics strategy. Sci Technol Adv Mater 2022;23:655-81. [Crossref] [PubMed]
12. Wang Y, Liu Z, Huang HW, et al. Towards clinical application: Emerging strategies for ultrasensitive and selective miRNA detection. Trends in Analytical Chemistry 2026;195:118593.
13. Kunou S, Shimada K, Takai M, et al. Exosomes secreted from cancer-associated fibroblasts elicit anti-pyrimidine drug resistance through modulation of its transporter in malignant lymphoma. Oncogene 2021;40:3989-4003. [Crossref] [PubMed]
14. Di Stefano G, Fischer A, Chteinberg E, et al. MicroRNA Expression in High-Grade B-Cell Lymphoma With 11q Aberration. Genes Chromosomes Cancer 2025;64:e70021. [Crossref] [PubMed]
15. Roy U, Raghavan SC. Regulation of B-cell development and differentiation by microRNAs during immune response and their implications in immunological disorders. J Immunol 2025;214:3199-207. [Crossref] [PubMed]
16. Xiao W, Zheng Y, Zhang H, et al. An absolute quantification atlas of small non-coding RNAs across diverse mammalian tissues and cell lines. Nat Commun 2026;17:2314. [Crossref] [PubMed]
17. Shen YG, Ji MM, Shi Q, et al. Clinicopathological characteristics, genetic aberrations, and optimized treatment strategies in double-hit and triple-hit lymphoma: a multi-center cohort study. Mol Biomed 2025;6:137. [Crossref] [PubMed]
18. Arzuaga-Mendez J, Lopez-Santillan M, Garcia-Ruiz JC, et al. Systematic review of the potential of MicroRNAs in the management of patients with follicular lymphoma. Crit Rev Oncol Hematol 2021;159:103247. [Crossref] [PubMed]
19. Alsaadi M, Khan MY, Dalhat MH, et al. Dysregulation of miRNAs in DLBCL: Causative Factor for Pathogenesis, Diagnosis and Prognosis. Diagnostics (Basel) 2021;11:1739. [Crossref] [PubMed]
20. Khanmohammadi S, Masrour M, Fallahtafti P, et al. MicroRNA as a Potential Diagnostic and Prognostic Biomarker in Diffuse Large B-Cell Lymphoma: A Systematic Review and Meta-Analysis. Cancer Rep (Hoboken) 2025;8:e70070. [Crossref] [PubMed]
21. Cao D, Cao X, Jiang Y, et al. Circulating exosomal microRNAs as diagnostic and prognostic biomarkers in patients with diffuse large B-cell lymphoma. Hematol Oncol 2022;40:172-80. [Crossref] [PubMed]
22. Zhang X, Zhang X, Huang X, et al. MiR-17∼92 is involved in NF-κB activation via targeting the ubiquitin-editing proteins to mediate RIP1 complex polyubiquitinations in ABC-DLBCL. Clin Immunol 2024;265:110297. [Crossref] [PubMed]
23. Pan Y, Cengiz R, Kluiver J, et al. Pinpointing Functionally Relevant miRNAs in Classical Hodgkin Lymphoma Pathogenesis. Cancers (Basel) 2024;16:1126. [Crossref] [PubMed]
24. Öz H, Canacankatan N, Antmen Ş E, et al. ‘Investigation of miRNAs That Affect the PI3K/AKT/mTOR Signaling Pathway in Endometrial Cancer’. Cell Biochem Biophys 2025;83:3125-36. [Crossref] [PubMed]
25. Akyüz N, Janjetovic S, Ghandili S, et al. EBV and 1q Gains Affect Gene and miRNA Expression in Burkitt Lymphoma. Viruses 2023;15:1808. [Crossref] [PubMed]
26. Wu Z, Zhang X, Liu P, et al. Pathogenesis and Diagnostic Significance of EBV-miR-BARTs in Nasopharyngeal Carcinoma. Oxid Med Cell Longev 2022;2022:4479905. [Crossref] [PubMed]
27. Yang FK, Tian C, Zhou LX, et al. The value of urinary exosomal microRNA-21 in the early diagnosis and prognosis of bladder cancer. Kaohsiung J Med Sci 2024;40:660-70. [Crossref] [PubMed]
28. Suljič A, Hočevar A, Jurčić V, et al. Evaluation of Arterial Histopathology and microRNA Expression That Underlie Ultrasonography Findings in Temporal Arteries of Patients with Giant Cell Arteritis. Int J Mol Sci 2023;24:1572. [Crossref] [PubMed]
29. Pliakou E, Lampropoulou DI, Dovrolis N, et al. Circulating miRNA Expression Profiles and Machine Learning Models in Association with Response to Irinotecan-Based Treatment in Metastatic Colorectal Cancer. Int J Mol Sci 2022;24:46. [Crossref] [PubMed]
30. Veryaskina YA, Titov SE, Kovynev IB, et al. MicroRNAs in Diffuse Large B-Cell Lymphoma (DLBCL): Biomarkers with Prognostic Potential. Cancers (Basel) 2025;17:1300. [Crossref] [PubMed]
31. Hromadnikova I, Kotlabova K, Krofta L. First-Trimester Screening for Miscarriage or Stillbirth-Prediction Model Based on MicroRNA Biomarkers. Int J Mol Sci 2023;24:10137. [Crossref] [PubMed]
32. Chen L, Kan Y, Wang X, et al. Overexpression of microRNA-130a predicts adverse prognosis of primary gastrointestinal diffuse large B-cell lymphoma. Oncol Lett 2020;20:93. [Crossref] [PubMed]
33. Zhou W, Xu Y, Zhang J, et al. MiRNA-363-3p/DUSP10/JNK axis mediates chemoresistance by enhancing DNA damage repair in diffuse large B-cell lymphoma. Leukemia 2022;36:1861-9. [Crossref] [PubMed]
34. Jabłońska E, Białopiotrowicz E, Szydłowski M, et al. DEPTOR is a microRNA-155 target regulating migration and cytokine production in diffuse large B-cell lymphoma cells. Exp Hematol 2020;88:56-67.e2. [Crossref] [PubMed]
35. Wei H, Wang J, Xu Z, et al. miR-584-5p regulates hepatocellular carcinoma cell migration and invasion through targeting KCNE2. Mol Genet Genomic Med 2019;7:e702. [Crossref] [PubMed]
36. Koumpis E, Georgoulis V, Papathanasiou K, et al. The Role of microRNA-155 as a Biomarker in Diffuse Large B-Cell Lymphoma. Biomedicines 2024;12:2658. [Crossref] [PubMed]
37. Baena JC, Cabrera-Salcedo SC, Carrera Suárez Y, et al. The avatar principle: exosomal dynamics guiding tumor adaptation and next-generation therapeutic strategies. J Nanobiotechnology 2026;24:159. [Crossref] [PubMed]
38. Feng Y, Zhong M, Tang Y, et al. The Role and Underlying Mechanism of Exosomal CA1 in Chemotherapy Resistance in Diffuse Large B Cell Lymphoma. Mol Ther Nucleic Acids 2020;21:452-63. [Crossref] [PubMed]
39. Liu J, Han Y, Hu S, et al. Circulating Exosomal MiR-107 Restrains Tumorigenesis in Diffuse Large B-Cell Lymphoma by Targeting 14-3-3η. Front Cell Dev Biol 2021;9:667800. [Crossref] [PubMed]
40. Shao R, Liu C, Xue R, et al. Tumor-derived Exosomal ENO2 Modulates Polarization of Tumor-associated Macrophages through Reprogramming Glycolysis to Promote Progression of Diffuse Large B-cell Lymphoma. Int J Biol Sci 2024;20:848-63. [Crossref] [PubMed]
41. Xu J, Liu S, Jin Y, et al. MicroRNAs and lysosomal membrane proteins: Critical interactions in tumor progression and therapy. Biochim Biophys Acta Rev Cancer 2025;1880:189303. [Crossref] [PubMed]
42. Ling H, Li Y, Wang P, et al. Diffuse large B-cell lymphoma cell-derived exosomal NSUN2 stabilizes PDL1 to promote tumor immune escape and M2 macrophage polarization in a YBX1-dependent manner. Arch Biochem Biophys 2025;766:110322. [Crossref] [PubMed]
43. Sun D, Bo L, Jiang C, et al. Beyond the boundary: The emerging roles of ATP-binding cassette transporters in multidrug resistance (MDR) and therapeutic targeting in cancer. Drug Resist Updat 2026;84:101310. [Crossref] [PubMed]
44. Punnachet T, Chattipakorn SC, Chattipakorn N, et al. Critical Role of Extracellular Vesicles in Diffuse Large B-Cell Lymphoma; Pathogenesis, Potential Biomarkers, and Targeted Therapy-A Narrative Review. Biomedicines 2024;12:2822. [Crossref] [PubMed]
45. Zhang C, Wang K, Tao J, et al. MYC-dependent MiR-7-5p regulated apoptosis and autophagy in diffuse large B cell lymphoma by targeting AMBRA1. Mol Cell Biochem 2025;480:191-202. [Crossref] [PubMed]
46. Ting CY, Tan SY, Gan GG, et al. Downregulation of hsa-miR-548d-3p and overexpression of HOXA9 in diffuse large B-cell lymphoma patients and the risk of R-CHOP chemotherapy resistance and disease progression. Int J Lab Hematol 2022;44:907-17. [Crossref] [PubMed]
47. Sun R, Zhang PP, Weng XQ, et al. Therapeutic targeting miR130b counteracts diffuse large B-cell lymphoma progression via OX40/OX40L-mediated interaction with Th17 cells. Signal Transduct Target Ther 2022;7:80. [Crossref] [PubMed]
48. Zhang KJ, Hu Y, Luo N, et al. miR-574-5p attenuates proliferation, migration and EMT in triple-negative breast cancer cells by targeting BCL11A and SOX2 to inhibit the SKIL/TAZ/CTGF axis. Int J Oncol 2020;56:1240-51. [Crossref] [PubMed]
49. Anastasiadou E, Seto AG, Beatty X, et al. Cobomarsen, an Oligonucleotide Inhibitor of miR-155, Slows DLBCL Tumor Cell Growth In Vitro and In Vivo. Clin Cancer Res 2021;27:1139-49. [Crossref] [PubMed]
50. Zhang S, Zhang R, Xu R, et al. MicroRNA-574-5p in gastric cancer cells promotes angiogenesis by targeting protein tyrosine phosphatase non-receptor type 3 (PTPN3). Gene 2020;733:144383. [Crossref] [PubMed]
51. Huang W, Zhao Y, Xu Z, et al. The Regulatory Mechanism of miR-574-5p Expression in Cancer. Biomolecules 2022;13:40. [Crossref] [PubMed]
52. Zhang L, Zhou S, Zhou T, et al. Potential of the tumor‑derived extracellular vesicles carrying the miR‑125b‑5p target TNFAIP3 in reducing the sensitivity of diffuse large B cell lymphoma to rituximab. Int J Oncol 2021;58:31. [Crossref] [PubMed]
53. Zhang M, Zeng J, Zhao Z, et al. Loss of MiR-424-3p, not miR-424-5p, confers chemoresistance through targeting YAP1 in non-small cell lung cancer. Mol Carcinog 2017;56:821-32. [Crossref] [PubMed]
54. Zhao X, Xu M, Hu X, et al. Human bone marrow-derived mesenchymal stem overexpressing microRNA-124-3p inhibit DLBCL progression by downregulating the NFATc1/cMYC pathway. Stem Cell Res Ther 2023;14:148. [Crossref] [PubMed]
55. Jiarui L, Yang H, Shunfeng H, et al. Exosomal MiR-107 As Novel Biomarker and Tumor Suppressor By Targeting Ywhah in Diffuse Large B-Cell Lymphoma. Blood 2020;136:26-7.
56. Wang Y, Guo D, Li B, et al. MiR-665 suppresses the progression of diffuse large B cell lymphoma (DLBCL) through targeting LIM and SH3 protein 1 (LASP1). Leuk Res 2022;112:106769. [Crossref] [PubMed]
57. Yazdanparast S, Huang Z, Keramat S, et al. The Roles of Exosomal microRNAs in Diffuse Large B-Cell Lymphoma: Diagnosis, Prognosis, Clinical Application, and Biomolecular Mechanisms. Front Oncol 2022;12:904637. [Crossref] [PubMed]
58. Yeganeh F, Parsian H. Counting Copies, Making Medicines: A Roadmap for the MSC-EV-microRNAome. Int J Mol Cell Med 2025;14:793-6. [Crossref] [PubMed]
59. Albanese M, Chen YA, Hüls C, et al. MicroRNAs are minor constituents of extracellular vesicles that are rarely delivered to target cells. PLoS Genet 2021;17:e1009951. [Crossref] [PubMed]
60. Geekiyanage H, Rayatpisheh S, Wohlschlegel JA, et al. Extracellular microRNAs in human circulation are associated with miRISC complexes that are accessible to anti-AGO2 antibody and can bind target mimic oligonucleotides. Proc Natl Acad Sci U S A 2020;117:24213-23. [Crossref] [PubMed]
61. Miceli RT, Chen TY, Nose Y, et al. Extracellular vesicles, RNA sequencing, and bioinformatic analyses: Challenges, solutions, and recommendations. J Extracell Vesicles 2024;13:e70005. [Crossref] [PubMed]
62. Abeysinghe P, Turner N, Mitchell MD. A comparative analysis of small extracellular vesicle (sEV) micro-RNA (miRNA) isolation and sequencing procedures in blood plasma samples. Extracell Vesicles Circ Nucl Acids 2024;5:119-37. [Crossref] [PubMed]
63. Théry C, Witwer KW, Aikawa E, et al. Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines. J Extracell Vesicles 2018;7:1535750. [Crossref] [PubMed]
64. Di K, Fan B, Gu X, et al. Highly efficient and automated isolation technology for extracellular vesicles microRNA. Front Bioeng Biotechnol 2022;10:948757. [Crossref] [PubMed]
65. Liu Q, Dai G, Wu Y, et al. iRGD-modified exosomes-delivered BCL6 siRNA inhibit the progression of diffuse large B-cell lymphoma. Front Oncol 2022;12:822805. [Crossref] [PubMed]
66. Wu T, Liu X, Chen H, et al. An in situ exosomal miRNA sensing biochip based on multi-branched localized catalytic hairpin assembly and photonic crystals. Biosens Bioelectron 2023;222:115013. [Crossref] [PubMed]
67. Zhou Y, Wang R, Zeng M, et al. Circulating tumor DNA: a revolutionary approach for early detection and personalized treatment of bladder cancer. Front Pharmacol 2025;16:1551219. [Crossref] [PubMed]
68. Hansen DR, Svenningsen P. New guidelines to uncover the physiology of extracellular vesicles. Acta Physiol (Oxf) 2024;240:e14153. [Crossref] [PubMed]
69. Maher N, Maiellaro F, Ghanej J, et al. Unraveling the Epigenetic Landscape of Mature B Cell Neoplasia: Mechanisms, Biomarkers, and Therapeutic Opportunities. Int J Mol Sci 2025;26:8132. [Crossref] [PubMed]
70. Peixoto da Silva S, Caires HR, Bergantim R, et al. miRNAs mediated drug resistance in hematological malignancies. Semin Cancer Biol 2022;83:283-302. [Crossref] [PubMed]
71. Zhao Y, Su A, Adili G, et al. Plasma-derived exosomal miRNA as a promising diagnostic biomarker for detection of diffuse large B-cell lymphoma. Transl Cancer Res 2026;15:141. [Crossref] [PubMed]
72. Kawasaki N, Tomita M, Yamashita-Kashima Y, et al. Efficacy of retreatment with polatuzumab vedotin in combination with rituximab in polatuzumab vedotin-resistant DLBCL models. Leuk Lymphoma 2023;64:1938-48. [Crossref] [PubMed]
73. Lobastova L, Lettau M, Babatz F, et al. CD30-Positive Extracellular Vesicles Enable the Targeting of CD30-Negative DLBCL Cells by the CD30 Antibody-Drug Conjugate Brentuximab Vedotin. Front Cell Dev Biol 2021;9:698503. [Crossref] [PubMed]
74. Global burden of lower respiratory infections and aetiologies, 1990-2023: a systematic analysis for the Global Burden of Disease Study 2023. Lancet Infect Dis 2026;26:343-61.
75. Aitamer M, Akil H, Vignoles C, et al. CD20 expression, TrkB activation and functional activity of diffuse large B cell lymphoma-derived small extracellular vesicles. Br J Cancer 2021;125:1687-98. [Crossref] [PubMed]
76. Martínez LE, Lensing S, Chang D, et al. CD20-bearing extracellular vesicles are associated with prognostic biomarkers of patients with AIDS-NHL. Sci Rep 2025;15:25181. [Crossref] [PubMed]