Search Results (1,402)

Penile squamous cell carcinoma (PSCC) is a rare malignancy with limited therapeutic options in advanced and recurrent diseases. Advanced PSCC is typically managed with multimodal therapy, including neoadjuvant chemotherapy or chemoradiation followed by surgery; however, durable responses remain uncommon, and outcomes after recurrence are poor. Cancer vaccines represent a promising immunotherapeutic strategy, as these treatments induce tumor-specific immunity and heightened immune surveillance against penile cancer cells. While therapeutic cancer vaccines have not yet demonstrated consistent clinical efficacy as monotherapy in PSCC, their integration with complementary immune-modulating approaches, particularly immune checkpoint blockade, represents a rational strategy to enhance antitumor immunity. This review summarizes the rationale for vaccine development in PSCC, with emphasis on HPV-derived antigens, neoantigens, and emerging tumor-associated targets. We examine major vaccine platforms, including viral-vector, peptide-based, nucleic acid, and dendritic cell-based approaches. We also discuss how spatial transcriptomics, single-cell RNA sequencing, artificial intelligence-assisted antigen prediction, and nanotechnology-enhanced delivery systems may support future personalized vaccine development. Overall, therapeutic vaccines remain investigational in PSCC but may become relevant within biomarker-driven, combination-based immunotherapy strategies. Full article

Background: Non-small cell lung cancer (NSCLC) remains one of the leading causes of cancer-related mortality worldwide over the past decade. Single-cell sequencing loses spatial location information and potential cell–cell interactions, making it difficult to interpret molecular features or biological phenomena. Tertiary lymphoid structures (TLSs) inherently require such spatial immune cell distribution information. Although associations between TLS and response to immune checkpoint inhibitors (ICIs) or chemotherapy have been reported, the relationship between TLS and neoadjuvant therapy (ICI combined with chemotherapy) remains unclear. Methods: We performed spatial transcriptomics on NSCLC samples (including one lung squamous cell carcinoma (LUSC) and one lung adenocarcinoma (LUAD)). Multiplex immunohistochemistry (mIHC) was used to identify the TLS, while immunohistochemistry staining (IHC) was used to identify the TLS status and cell characteristics. We evaluated the associations between (mature) TLS density, area proportion and patients’ responses in 66 patients. Results: Heterogeneity of immune cells in NSCLC was found. Gene ontology analysis and cell score comparison identified TLS with activated B and T cells inside, while plasma cells and macrophages were mainly distributed outside TLS. Four genes from antigen-presenting machinery (TAP1, TAP2, B2M, TAPBP) were more highly expressed inside TLS than outside them. Also, TLS exhibited heterogeneity, with both mature and immature TLS. Mature TLS showed an average area of 62,387.43 μm², while the immature TLS showed 51,189.90 μm². The Spearman correlation coefficient of B-cell number and mTLS area showed r = 0.900. TLS density and mature TLS (mTLS) density in the tumor bed were 1.95 ± 0.95 TLS/10 mm² (mean ± SD, n = 34) and 1.13 ± 0.77 mTLS/10 mm², significantly higher than that in the non-responder group (1.18 ± 1.15 TLS/10 mm², 0.70 ± 0.90 mTLS/10 mm², mean ± SD, n = 32) separately. B cells belonging to TLS had a significantly higher density (71.32 ± 55.71 cells/mm², mean ± SD, n = 34) in the responder group than the non-responder group (61.33 ± 111.95 cells/mm², mean ± SD, n = 32) normalized to the tumor bed area. Conclusions: Spatial transcriptomics reveals immune cell heterogeneity and distribution patterns in the NSCLC tumor bed, with activated B and T cells localized inside and plasma cells/macrophages outside. Antigen-presenting machinery (APM)-related genes were highly expressed in TLS accompanied by a high expression of upstream and downstream genes of MHC class I. mTLS have a larger area by mainly containing more B cells. The responder group had a significantly higher (mature) TLS density and larger (mature) TLS area proportion compared with the non-responder group, suggesting their potential function in anti-tumor effect in neoadjuvant treatment. Full article

Background/Objectives: Outcomes after CD19-directed chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory (R/R) aggressive large B-cell lymphoma (aLBCL) remain heterogeneous. Tumor genomic biomarkers, such as TP53 alteration, MYC/BCL2/BCL6 rearrangement-defined double-hit or triple-hit lymphoma (DHL/THL), cell of origin (COO), and complex karyotype, are established or candidate prognostic factors in conventionally treated lymphoma, but their relevance after CAR T-cell therapy is uncertain. We conducted a systematic review with exploratory meta-analysis of biomarker-stratified outcomes after CD19 CAR T-cell therapy in aLBCL. Methods: We searched MEDLINE, Embase, and Web of Science/BIOSIS (April 2026), with targeted PubMed citation lookup during full-text retrieval (PROSPERO CRD420261350514). Eligible studies enrolled adults with R/R disease treated with protocol-eligible CD19 CAR T-cell therapy and reported prespecified tumor genomic biomarkers with stratified outcomes. Random-effects models, using restricted maximum-likelihood estimation with Hartung–Knapp–Sidik–Jonkman (HKSJ) adjustment, were fitted when at least three comparable, non-overlapping studies provided extractable data. Results: After duplicate removal, 182 records were screened, 37 were assessed for eligibility, and 26 studies were included in the qualitative synthesis; 10 contributed to 4 pooled analyses. DHL/THL-positive disease was associated with worse unadjusted overall survival (OS) (hazard ratio [HR] 1.52; 95% confidence interval [CI], 1.21–1.89; 95% prediction interval (PI), 0.56–4.08), and non-Germinal center B-cell-like (GCB)/ABC COO with worse adjusted progression-free survival (PFS) (HR 1.44; 95% CI, 1.04–2.00; 95% PI, 0.86–2.43). The complete-response analyses for TP53 alteration (OR 1.30; 95% CI, 0.01–156.60) and COO (OR 1.27; 95% CI, 0.24–6.61) were statistically uninformative. No study permitted evaluation of complex karyotypes. Conclusions: Biomarker-stratified evidence after CD19 CAR T-cell therapy is sparse and inconsistently reported. DHL/THL status and non-GCB/activated B-cell-like (ABC) COO showed exploratory survival signals, whereas the TP53 and COO complete-response analyses were uninformative. These biomarkers remain hypothesis-generating rather than validated predictors of CAR T-cell outcome, and standardized, prospective biomarker-stratified reporting is needed. Full article

Background: Predicting tumor regression following neoadjuvant chemoradiotherapy (nCRT) remains a major challenge in the management of locally advanced rectal cancer (LARC). Readily available inflammatory biomarkers may provide useful information regarding treatment response. Methods: This retrospective single-center study included 88 patients with stage II–III rectal adenocarcinoma who underwent neoadjuvant chemoradiotherapy followed by curative-intent surgery between 2017 and 2025. Patients were classified according to the College of American Pathologists tumor regression grading system as CAP 0 (pathological complete response, n = 22), CAP 2 (partial response, n = 50), or CAP 3 (poor/no response, n = 16). Pretreatment C-reactive protein, carcinoembryonic antigen (CEA), neutrophil, platelet, monocyte, and lymphocyte counts, together with NLR, PLR, and PIV, were compared across groups. Receiver operating characteristic and logistic regression analyses were performed for pathological complete response (pCR). Results: None of the evaluated biomarkers differed significantly across CAP groups. The smallest omnibus p-values were observed for neutrophil count (p = 0.052), monocyte count (p = 0.075), and CEA (p = 0.088). Monocyte count showed the highest discriminatory performance for pathological complete response (AUC = 0.663), followed by CEA (AUC = 0.640). In sensitivity analyses adjusted for baseline clinical T stage and receipt of total neoadjuvant therapy, CEA, neutrophil count, and monocyte count were not independently associated with pathological complete response. More favorable tumor regression was associated with lower residual tumor burden and reduced nodal involvement. Conclusions: Pretreatment inflammatory biomarkers showed biologically plausible numerical patterns across tumor regression groups, but their discriminatory and independent predictive performance was limited. These markers should not be considered stand-alone clinical prediction tools and should be validated within larger, multimodal prospective models. Full article

Radiotherapy (RT) has traditionally been considered a local treatment modality; however, accumulating evidence suggests that it can induce systemic antitumor responses outside the irradiated field. The classical abscopal effect, defined as the regression of non-irradiated tumor lesions following localized RT, has gained renewed attention in the era of immune checkpoint inhibitors (ICIs). Preclinical and clinical studies have demonstrated that RT can promote immunogenic cell death, antigen presentation, cytokine release, and adaptive immune activation, processes that may contribute to systemic antitumor immunity, particularly when combined with ICIs. Clinically apparent abscopal responses remain rare and heterogeneous, and the biological mechanisms underlying these phenomena are not completely understood. Systemic tumor regression has occasionally been observed in clinical settings that do not involve checkpoint blockade, including RT alone, chemotherapy-containing regimens, and central nervous system-directed therapies. These findings suggest that radiation-associated systemic antitumor responses may arise through overlapping immunologic mechanisms involving both innate and adaptive immunity, tumor microenvironment remodeling, and treatment-associated cellular stress. This review summarizes the current clinical evidence and biological mechanisms underlying radiation-associated systemic antitumor responses and discusses emerging concepts extending beyond the conventional RT–immunotherapy paradigm. We further examined unresolved challenges, including treatment heterogeneity, biomarker limitations, pseudoprogression, and difficulties in mechanistic confirmation. Finally, we propose that the broader “beyond-abscopal” framework may serve as a hypothesis-generating conceptual model for investigating systemic tumor responses across diverse treatment contexts while emphasizing the need for cautious interpretation and prospective translational validation. Full article

Background: The HPV16 E6 oncoprotein facilitates the ubiquitin-mediated degradation of the tumor suppressor p53, constituting a pivotal mechanism underlying viral immune evasion, cellular immortalization, and ultimately, malignant transformation. This study aimed to develop a reliable detection tool for the HPV16 E6 protein. Methods: Recombinant GST-E6 and E6-His proteins were expressed and purified using a prokaryotic expression system. Female BALB/c mice were immunized with GST-E6, and two hybridoma cell lines (G11A11 and A4) stably secreting anti-HPV16 E6 monoclonal antibodies were generated via hybridoma technology. Antibody pairing experiments identified A4 and G11A11 as suitable for sandwich ELISA. The optimal detection system was established using A4 antibody at 2 μg/mL for coating, HPV16 E6-His at 5 μg/mL as the detection antigen, and G11A11-HRP at a 1:200 dilution as the detection antibody. To validate the reliability, Hacat-HPV16E6 cell lysates were tested in parallel with a commercial ELISA kit. Results: After purification, the titers of both antibodies reached 1:204,800. The lower limit of quantification (LOQ) was 4.79 ng/mL and the limit of detection (LOD) was 3.39 ng/mL. The comparison with the commercial kit showed good consistency, with percentage differences ranging from 20% to 40%, confirming that the established ELISA is reliable for quantitative detection. Conclusions: This study successfully yielded high-titer and highly specific anti-HPV16 E6 monoclonal antibodies and developed a specific double-antibody sandwich ELISA, thereby furnishing a technical foundation for both fundamental research and laboratory-based applications related to HPV16-associated tumors. Full article

Allogeneic T cell therapies have emerged as a promising strategy to overcome the logistical and manufacturing limitations of autologous approaches, enabling scalable, off-the-shelf cancer immunotherapy. While early clinical efforts have focused predominantly on αβ T cell-based platforms, including CAR- and TCR-engineered approaches, a growing spectrum of alternative cell types, such as γδ T cells, invariant natural killer T cells, mucosal-associated invariant T cells, and induced pluripotent stem cell-derived effectors, is expanding the design landscape of allogeneic therapies. However, clinical translation remains constrained by immune rejection, limited persistence, lymphodepletion-associated toxicity, manufacturing variability, and impaired efficacy in solid tumors. To address these barriers, engineering strategies have increasingly integrated T cell receptor disruption, human leukocyte antigen modulation, cytokine support, checkpoint editing, and synthetic circuit design. This review provides an oncology-focused, cross-platform framework for evaluating diverse allogeneic T cell and T cell-like platforms according to clinical maturity, safety, manufacturability, persistence, and tumor-targeting capacity. We further discuss how platform-specific biological properties and clinical evidence can be integrated with modular engineering strategies to optimize antitumor performance. These insights support a shift from platform-centric development toward a design-driven paradigm for next-generation allogeneic cellular immunotherapies with improved efficacy, safety, and scalability. Full article

To evaluate the diagnostic performance and clinicopathologic relevance of a multi-locus circulating tumor DNA methylation assay, in this prospective, single-center, case-control exploratory study, we enrolled 35 patients with colorectal cancer undergoing surgery and 57 healthy controls undergoing screening colonoscopy at the Asan Medical Center, Seoul, Republic of Korea between July 2024 and January 2025. Peripheral blood was collected before surgery or colonoscopy, and circulating tumor DNA methylation was analyzed using a multi-locus panel targeting Septin9, IKZF1, BCAT1, Septin9-2, BCAN, and VAV3. The main outcomes were test accuracy (sensitivity, specificity, and area under the curve [AUC]) and associations between methylation marker positivity and clinicopathologic features. Circulating tumor DNA was positive in 74.3% of the patients and 12.3% of controls, yielding a sensitivity of 74.3%, specificity of 87.7%, and an AUC of 0.837, whereas serum carcinoembryonic antigen exhibited lower sensitivity (25.7%). Sensitivity in stage I disease was limited (36.4%). Circulating tumor DNA-positive tumors were larger (5.7 cm vs. 2.2 cm, p < 0.001) and had more advanced T and N stages. The number of positive markers increased with pathologic stage (p = 0.003). Individual marker analysis revealed that BCAT1, Septin9-2, and VAV3 were associated with higher T stage, whereas BCAN positivity was linked to nodal metastasis. The six-marker circulating tumor DNA methylation assay demonstrated acceptable diagnostic accuracy, with multi-locus patterns associated with tumor burden and invasive features. However, sensitivity for early-stage disease was limited. The assay may serve as a complementary tool for screening and risk stratification. Full article

Hepatocellular carcinoma (HCC) is sustained by coordinated interactions among malignant hepatocytes, immune cells, and stromal populations that collectively drive tumor growth, immune evasion, and vascular remodeling. Using integrative single-cell transcriptomics on 93,032 cells from tumor and healthy human liver, we characterized cell-type-specific transcriptional programs underlying immunometabolic reprogramming and reconstructed the intercellular communication circuits that maintain the tumor microenvironment. Malignant hepatocytes displayed upregulation of genes encoding both glycolytic and oxidative phosphorylation (OXPHOS) metabolic enzymes, consistent with metabolic plasticity, while concurrently suppressing genes involved in antigen presentation—a transcriptional pattern indicative of coordinated metabolic and immune-evasive reprogramming. Tumor-associated macrophages acquired TREM2-enriched, lipid-handling phenotypes consistent with immunosuppressive polarization, and tumor endothelial cells upregulated angiocrine and extracellular matrix programs while silencing innate immune outputs. Ligand–receptor inference revealed a qualitative rewiring of intercellular communication: the antigen-presentation-centered network of the healthy liver was replaced by a tumor-driven architecture dominated by pro-angiogenic, ECM–integrin, inflammatory chemokine, and lipid-associated signaling circuits, with malignant hepatocytes, TAMs, and TECs collectively assuming the dominant signaling burden. These findings establish that HCC progression is an emergent property of a stabilized multicellular network, rather than the autonomous behavior of malignant cells, and define cooperative immunometabolic modules that constitute tractable targets for combinatorial therapeutic intervention. Full article

Background/Objectives: Cribriform architecture is an adverse Gleason pattern 4 morphology associated with aggressive prostate cancer outcomes. Tertiary Gleason pattern 5, even as a minor component, may also identify tumors with higher-grade biology not fully captured by conventional Grade Group assignment. We examined whether cribriform architecture is associated with tertiary Gleason pattern 5 in patients undergoing radical prostatectomy. Methods: We performed a retrospective cross-sectional study of radical prostatectomy specimens from patients with prostate adenocarcinoma who underwent radical prostatectomy and had available clinicopathologic data. A centralized pathology review of digitized radical prostatectomy slides was used to assess cribriform architecture. Tertiary Gleason pattern 5 status was obtained from original pathology reports. Multivariable logistic regression was used to evaluate the association between cribriform architecture and tertiary Gleason pattern 5 after adjustment for age, preoperative prostate-specific antigen level, prostatectomy Gleason score, pathologic tumor stage, and margin status. Results: Among 303 patients, 47 (15.5%) had tertiary Gleason pattern 5. Cribriform architecture was more common in tumors with tertiary Gleason pattern 5 than in those without (70% vs. 21%; p < 0.001). On multivariable analysis, cribriform architecture remained independently associated with tertiary Gleason pattern 5 (adjusted odds ratio of 9.46; 95% confidence interval of 4.49–21.0; p < 0.001). The model demonstrated good discrimination, with an area under the receiver operating characteristic curve of 0.80. Conclusions: Cribriform architecture was strongly associated with tertiary Gleason pattern 5. These findings suggest that cribriform-positive tumors may be more likely to harbor minor high-grade pattern 5 components. Full article

Copper (Cu)–zinc (Zn) imbalance has been implicated in colorectal cancer (CRC). Exchangeable copper (exCu), the labile circulating Cu fraction, may better reflect functionally relevant metal dysregulation than total Cu. We investigated sex-specific associations between systemic Cu–Zn indices, tumor burden, and epithelial–mesenchymal transition (EMT)-related tissue remodeling in CRC. We studied 152 CRC patients and 140 healthy controls. Serum Cu, Zn, and exCu were measured using validated analytical methods; circulating gonadotropins, sex steroids, and carcinoembryonic antigen were also assessed. EMT-related proteins (E-cadherin, vimentin, fibronectin, vinculin, MEMO1) were quantified by Western blot in paired tumor and adjacent mucosa. Analyses were sex-stratified and age-adjusted. CRC patients exhibited higher serum Cu and exCu and lower Zn than controls, resulting in a marked increase in the exCu:Zn ratio in both sexes. In patients, exCu:Zn was associated with tumor burden and pathological stage, with stronger associations with tumor size and pT stage in women and with metastatic status in men. Serum exCu:Zn was associated with tumor − normal differences in EMT-related proteins, particularly ΔE-cadherin, in both sexes. Systemic Cu–Zn disequilibrium, summarized by the exCu:Zn ratio, was associated with tumor burden and epithelial remodeling in CRC in a sex-specific manner, suggesting its potential as a biologically informative biomarker warranting further validation. Full article

Macrophages are highly plastic innate immune cells that adopt context-dependent phenotypes along a continuum, integrating developmental origin with local microenvironmental cues rather than conforming to discrete M1/M2 states. This review delineates the molecular circuits shaping macrophage identity—TLR/cytokine signaling, microRNA networks, metabolic rewiring, and epigenetic mechanisms including histone lactylation—and traces how circulating monocyte subsets contribute to tissue macrophage diversity. We examine macrophage plasticity across a broad disease spectrum—oncology, autoimmune and rheumatic diseases, inflammatory bowel disease, infectious diseases, metabolic disorders, and neurological conditions—showing that the pathogenic phenotype is strikingly context-dependent: for instance, M2-like tumor-associated macrophages promote immune evasion in solid tumors, whereas M1-skewed programs drive tissue damage in autoimmunity. Soluble markers (sCD163, sCD14, soluble mannose receptor) are emerging biomarkers of disease activity and prognosis. High-dimensional flow cytometry and mass cytometry (CyTOF) bridge molecular biology and clinical phenotyping, enabling integrated readouts of surface phenotype, intracellular signaling, and metabolic state. Therapeutic strategies discussed include selective tumor-associated macrophage (TAM) reprogramming, chimeric antigen receptor (CAR)-M cell therapies, and biomaterial-based platforms. Future priorities encompass spatially resolved multi-omics, epigenetic and metabolic targeting, and macrophage-centered vaccine approaches. Standardized cytometry panels will be essential for biomarker-guided stratification and context-specific interventions. Full article

Neuroblastoma (NB), the most common extracranial solid tumor of childhood, exemplifies one of the most formidable paradigms of tumor immune evasion (TIME) in pediatric oncology. Despite significant advances in multimodal therapy and the clinical integration of immunotherapeutic strategies, high-risk NB (HR-NB) remains largely refractory to durable immune control. This failure reflects not an absence of immune engagement, but the presence of a highly evolved and developmentally wired immune escape architecture. In this review, we synthesize emerging insights from single-cell, multi-omics, and functional studies to define how developmental lineage, cellular plasticity, metabolic rewiring, epigenetic regulation, and therapy-induced adaptation converge to engineer immune blindness in NB. We discuss how NB’s neural crest origin establishes a baseline of low immunogenicity, which is subsequently reinforced through coordinated suppression of antigen presentation, dominance of immune checkpoint signaling, and profound dysfunction of cytotoxic T and natural killer cells within an immunosuppressive tumor microenvironment. Central to this process is tumor-intrinsic plasticity, whereby lineage instability and dedifferentiation, exacerbated by therapeutic pressure, embed immune silence as a stable tumor state. We highlight evidence positioning RD3 as a master upstream regulator linking cellular identity to immune visibility, governing antigen presentation, innate immune sensing, checkpoint expression, and cytotoxic lymphocyte engagement. Beyond tumor-intrinsic mechanisms, we examine the roles of immunosuppressive myeloid populations, tumor-derived exosomes, metabolic stress, hypoxia, and ferroptosis-associated pathways in reinforcing immune paralysis. Finally, we outline emerging therapeutic strategies aimed at dismantling this architecture, including combinatorial checkpoint blockade, metabolic and epigenetic reprogramming, exosome-targeted interventions, and next-generation immune engineering platforms. Together, this review reframes TIME in NB as a programmable, developmentally rooted process and provides a mechanistic roadmap for restoring immune competence and therapeutic susceptibility in HR disease. Full article

Heat shock protein 90 (HSP90) is a molecular chaperone essential for maintaining the stability of many oncogenic client proteins. Although several HSP90 inhibitors (HSP90i) have entered clinical trials, their use has been limited by toxicity and resistance, underscoring the need for improved therapeutic strategies. In this study, we assessed the therapeutic potential of a new HSP90i, SP11, in T-cell acute lymphoblastic leukemia (T-ALL) in vitro and in the DLA mouse model in vivo, using single-cell transcriptomic profiling. Single-cell RNA sequencing showed that SP11 treatment reduces key oncogenic drivers, including MYC, BCL2, and stemness-related genes, consistent with impaired leukemic survival programs. In the DLA mouse model, SP11-mediated HSP90 inhibition was associated with alterations in the tumor microenvironment, including increased immune cell representation and enrichment of cytokine- and antigen-presentation-related transcriptional pathways. Despite these antitumor effects, a distinct subpopulation of cells continued to express or re-express MYC and BCL2, suggesting the development of early adaptive resistance. Consistent with these findings, an SP11-resistant MOLT4 cell line maintained high levels of MYC and BCL2 at both the transcript and protein levels, maintained CD44 expression, and exhibited altered inflammatory cytokine signaling. Functional studies confirmed that pharmacological inhibition of BCL2 notably increased SP11 sensitivity, supporting a rational combination strategy. Collectively, our results show that SP11 may exert both tumor-intrinsic and immune-modulating effects and reveal transcriptionally defined adaptive cellular states linked to resistance. This study provides mechanistic in sights into responses to HSP90 inhibition and supports combination approaches for improving therapeutic outcomes in T-ALL. Full article

Background: Previous work from our group demonstrated an association between immunohistochemical detection of Human cytomegalovirus (HCMV) late antigen and poor event-free survival (EFS) in pediatric medulloblastoma. Whole-genome sequencing (WGS) further identified increased abundance of HCMV-aligned reads at the UL88 locus, particularly in Group 3 tumors, a molecular subgroup associated with aggressive clinical behavior and poor prognosis. Methods: We performed an integrated multi-omics analysis of pediatric medulloblastoma using WGS (n = 39) and RNA sequencing (RNA-seq; n = 28) datasets. RNA-seq data were filtered using stringent alignment criteria (MAPQ ≥ 20) and compared with fetal brain (n = 12), adult brain (n = 12), and HCMV-infected cell culture controls (n = 3). Only high-confidence uniquely aligned reads were retained to reduce nonspecific and multi-mapped viral alignments. Sequencing reads were aligned to the HCMV Merlin reference genome (NC_006273.2) using a standardized analytical pipeline. A subset of 28 cases with matched tumor WGS, tumor RNA-seq, and germline WGS data was used for integrated multi-omics analyses. Orthogonal validation analyses were performed in Group 3 tumors using independent genomic and transcriptomic approaches. Exploratory survival analyses were conducted in a combined cohort (n = 84) integrating genomic and immunohistochemical datasets. Results: Recurrent low-level HCMV-aligned molecular signals were identified across medulloblastoma datasets. Reads aligning to UL76, UL88, and UL99 were the most consistently detected HCMV-associated late-gene signals across RNA-seq and WGS datasets. A composite HCMV late-gene signature (UL76–UL88–UL99) showed higher levels in Group 3 tumors than in other molecular subgroups (p < 0.05 in WGS analyses). Orthogonal analyses demonstrated concordant low-level HCMV-associated genomic and transcriptomic signals enriched in tumors with MYC-associated activation and chromosome 17 imbalance. In the combined cohort (n = 84), elevated HCMV-associated signal assessed by immunohistochemistry and genomic profiling was associated with reduced EFS (median 55 vs. 147 months; log-rank p < 0.001). The subgroup classified as HCMV-high Group 3 demonstrated the strongest association with adverse outcome in exploratory multivariable analyses (HR = 6.43, p = 0.002). Conclusions: This study identifies recurrent low-level HCMV-associated genomic and transcriptomic signals across pediatric medulloblastoma datasets, with preferential enrichment in biologically aggressive Group 3 tumors. Although the extremely low abundance of viral-aligned reads precludes definitive evidence of productive viral infection, the reproducible detection of HCMV-associated molecular signatures across independent sequencing platforms supports further investigation into a potential oncomodulatory association in pediatric medulloblastoma. Additional validation using optimized viral detection methodologies, independent cohorts, and mechanistic studies will be necessary to clarify the biological and clinical significance of these findings. Full article