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highSpaClone enables copy number alteration inference and tumor subclone analysis for high-resolution spatial transcriptomics.

High-resolution spatially resolved transcriptomics (SRT) offers unprecedented opportunities to investigate tumor heterogeneity but poses substantial computational and analytical challenges. Here, we present highSpaClone, a computational framework for copy number alteration (CNA) inference and tumor subclone identification from high-resolution SRT data across multiple spatial scales. By integrating spatial constraints into CNA estimation and clonal clustering, highSpaClone enables neighboring spatial locations to share information, thereby improving the robustness of genomic signals and the accuracy of subclone delineation. Across multiple Xenium and Visium HD datasets, highSpaClone revealed unique transcriptional programs, clonal evolutionary trajectories, and distinct tumor-microenvironment interactions. Furthermore, in human colorectal cancer samples, highSpaClone detected CNA events in histologically normal epithelial regions, highlighting early genomic alterations associated with field cancerization. These findings establish highSpaClone as a scalable framework for studying clonal architecture and tumor evolution.

CP: cancer biology

A comprehensive survey of genetic variants in neuroblastoma.

BACKGROUND: Neuroblastoma (NB) is the most common extracranial solid tumor in children and is characterized by marked clinical and molecular heterogeneity. Genomic alterations play a critical role in NB pathogenesis; however, population-specific mutational features remain insufficiently characterized, particularly among Chinese patients. METHODS: Whole-exome sequencing (WES) was performed on tumor, para-tumor, and matched peripheral blood samples from nine pathologically confirmed Chinese patients with NB. Somatic variant profiles were compared with four publicly available NB datasets from cBioPortal, published in 2012, 2013, 2015, and 2023. Mutational patterns, recurrently altered genes, and Gene Ontology (GO) enrichment were analyzed using R version 4.3.2 and clusterProfiler version 4.10.0. RESULTS: A total of 77 missense variants were identified in our cohort. Single-nucleotide polymorphisms (SNPs) represented the predominant variant type, and C > T substitutions were the most frequent nucleotide change. MAP1A variants, comprising two missense variants in one patient, and RBM33 variants, comprising two distinct variants in two patients, were detected in our cohort and, to the best of our knowledge, have not been previously reported in NB, although their frequencies were low. No MYCN amplification or variants in ALK, ATRX, or DAXX were detected. Comparative analysis with the cBioPortal datasets revealed no somatic variants universally shared across all cohorts. In addition, high-risk patients exhibited distinct mutational patterns, with enrichment of the Gene Ontology term "collagen-containing extracellular matrix." CONCLUSIONS: These findings highlight the molecular diversity of NB and suggest the presence of potential population-specific genetic features in Chinese patients. The low-frequency MAP1A and RBM33 variants identified in this cohort warrant further validation in larger, independent cohorts. Moreover, the enrichment of extracellular matrix-related pathways in high-risk NB supports further investigation of tumor-microenvironment interactions as potential therapeutic targets.

Extracellular matrix

Understanding tumor adaptations and resistance to MET inhibitors in MET-altered non-small cell lung cancer.

AIM: Type Ib MET inhibitors are clinically active in selected MET-altered non-small cell lung cancer, particularly tumors with MET exon 14 skipping or MET amplification, but acquired resistance remains incompletely understood. Here, we investigated resistance across biologically distinct MET-altered contexts, including MET exon 14 skipping, MET amplification, and MET overexpression. METHODS: Paired baseline and progression samples from seven patients treated with tepotinib or capmatinib were analyzed using spatial transcriptomics, whole-exome sequencing, RNA sequencing, CRISPR screening, and drug-combination assays. Patient-derived cultures and resistant cell-line models were used to explore resistance-associated changes. RESULTS: MET inhibitor resistance was heterogeneous, with persistence of the initial MET alteration in most evaluable cases and emergence of patient-specific genomic events. Three main resistance-associated, often overlapping, routes were identified: on-target MET evolution through kinase-domain alterations; extracellular matrix and tumor-microenvironment remodeling, including collagen and fibronectin upregulation, complement-related signaling, and partial EMT-associated programs; and bypass signaling involving EGFR/HER, MAPK, and PI3K/Akt pathways. In vitro models reproduced several tumor-cell-intrinsic features but only partially captured microenvironment-associated changes. CONCLUSIONS: MET inhibitor resistance in this cohort involved overlapping, context-dependent genomic, phenotypic, and signaling adaptations, supporting combination strategies for MET-altered lung cancer.

CRISPR screen

Competing subclones and fitness diversity shape tumor evolution across cancer types.

MOTIVATION: Intratumor heterogeneity arises from ongoing somatic evolution and complicates cancer diagnosis, prognosis, and treatment. Reconstructing evolutionary dynamics typically requires spatiotemporal samples, which are often unavailable in clinical settings. Computational approaches that can infer tumor evolutionary history from single-timepoint bulk sequencing data remain limited. RESULTS: We present estimating evolutionary events through single-timepoint sequencing (TEATIME), a novel computational framework that models tumors as mixtures of two competing cell populations: an ancestral clone with baseline fitness and a derived subclone with elevated fitness. Using cross-sectional bulk sequencing data, TEATIME estimates mutation rates, timing of subclone emergence, relative fitness, and number of generations of growth. To quantify intratumor fitness asymmetries, we introduce a novel metric-fitness diversity-which captures the imbalance between competing cell populations and serves as a measure of functional intratumor heterogeneity. Applying TEATIME to 33 tumor types from The Cancer Genome Atlas, we revealed divergent as well as convergent evolutionary patterns. Notably, we found that immune-hot microenvironments constraint subclonal expansion and limit fitness diversity. Moreover, we detected temporal dependencies in mutation acquisition, where early driver mutations in ancestral clones epistatically shape the fitness landscape, predisposing specific subclones to selective advantages. These findings underscore the importance of intratumor competition and tumor-microenvironment interactions in shaping evolutionary trajectories, driving intratumor heterogeneity. Lastly, we demonstrate that TEATIME-derived evolutionary parameters and fitness diversity offer novel prognostic insights across multiple cancer types. AVAILABILITY AND IMPLEMENTATION: R implementation of TEATIME is available on GitHub (https://github.com/liliulab/TEATIME) and Zenodo (https://zenodo.org/records/17422174).

Neoplasms

Decoding glioblastoma evolution and heterogeneity through mechanistic modeling: implications for clinical translation.

Glioblastoma (GBM) is one of the most aggressive and lethal primary brain tumors in adults, characterized by dynamic clonal evolution and extensive genomic, cellular, spatial, and microenvironmental heterogeneity. Multi-omics studies have revealed that GBM follows complex evolutionary trajectories involving genetic, epigenetic, transcriptional, and immune-microenvironmental remodeling as tumors grow, adapt to the brain microenvironment, and acquire therapeutic resistance. Increasing evidence suggests that GBM may originate from aberrant neural stem or progenitor cells, including those residing in the subventricular zone, and that glioblastoma stem cells (GSCs) contribute to tumor propagation, heterogeneity, and recurrence. A key conceptual challenge is to reconcile hierarchical cancer stem cell models, in which GSCs are viewed as relatively stable tumor-propagating subpopulations, with dynamic state plasticity models, in which stem-like properties can be reversibly acquired or lost during transitions among proneural-like, mesenchymal-like, invasive, and therapy-tolerant states. Recent advances in single-cell profiling, spatial transcriptomics, lineage tracing, organoid culture, 3D bioprinting, genetically engineered models, and artificial intelligence (AI)-assisted computational modeling have substantially improved the ability to study these processes. However, no currently available model fully recapitulates human GBM heterogeneity, recurrence, treatment history, and tumor-microenvironment interactions. Therefore, model selection should be guided by clearly defined mechanistic questions rather than by reliance on any single platform. This review summarizes current advances in in vitro, ex vivo, in vivo, and computational models for studying GBM evolution and heterogeneity, and discusses how integrated model pipelines may improve preclinical drug testing, treatment-response prediction, and precision neuro-oncology.

Humans

TFPI-high myofibroblast states and a meta-program-related five-gene prognostic signature in breast cancer.

Intratumoral heterogeneity and tumor-microenvironment interactions limit prognostic stratification in breast cancer, but the prognostic relevance and cellular context of recurrent transcriptional meta-programs remain unclear. We aimed to derive a meta-program-related prognostic signature and characterize its component transcripts at single-cell resolution. Six paired institutional tumors and adjacent non-tumor tissues served as a proof-of-concept comparison. Univariable Cox screening and least absolute shrinkage and selection operator Cox regression were used to derive a five-gene score from a prespecified meta-program-related candidate set in The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) training cohort; the score was tested internally and assessed in GSE20685 using fixed coefficients and cohort-specific median cutoffs. GSE161529 single-cell transcriptomic data were used to map signature transcripts across 136,526 quality-controlled cells, while donor-aware pseudobulk analysis compared upper- and lower-quartile TFPI expression states in annotated myofibroblasts. The score comprised TCN1, FOXJ1, PIGR, SLAIN1, and TFPI and was associated with overall survival in the training, testing, and external cohorts, with concordance indices of 0.782, 0.756, and 0.721, respectively. TFPI transcripts were detected across endothelial, fibroblast, and myofibroblast compartments. TFPI-high myofibroblasts showed transcriptional enrichment of extracellular matrix and collagen fibril organization, transforming growth factor beta signaling, epithelial-mesenchymal transition, and myogenesis, together with lower oxidative phosphorylation and fatty acid metabolism programs. In bulk TCGA-BRCA tissue, TFPI expression correlated positively with stromal (r&#xa0;= 0.48), immune (r&#xa0;= 0.25), and composite microenvironment scores (r&#xa0;= 0.40; all p&#xa0;< 0.001). These findings identify a hypothesis-generating five-gene bulk-tissue prognostic signature and an expression-associated TFPI-high myofibroblast state but do not establish a discrete lineage, the cellular source of bulk TFPI, a TFPI-dependent mechanism, or clinical utility. Independent prospective cohorts, spatial and protein-level validation, and functional perturbation studies are required.

Journal Article

The IL-1 system in inflammation and cancer.

Inflammation is a pathogenetic driver of several pathological conditions, including cancer. The tumor microenvironment, which includes cellular, molecular, and structural components, is an essential component of cancer, involved in tumor promoting or controlling processes. In particular, inflammatory players contribute to the establishment of a tumor-promoting microenvironment, which affects all stages of tumor development, from initiation to metastasis, as well as response to therapy. The IL-1 system includes two large sets of structurally related ligands and receptors, with agonist or regulatory activity, playing non-redundant roles in inflammation and immunity. Each of them has specific functions in tissue homeostasis, inflammation, innate and adaptive immune responses, and potentially contributes to processes related to carcinogenesis and metastasis, or immune-mediated control of cancer cells. Depending on the context and cellular target, IL-1 family members may play dual roles in cancer, driving both pro- or anti-tumor processes. IL-1&#x3b1; and IL-1&#x3b2; can directly promote cancer cell proliferation, survival, and plasticity, in addition to contribute to the establishment of a pro-inflammatory environment that promotes tissue remodeling, cellular stress responses, and genomic instability. On the other hand, IL-1 is a lymphoproliferative and activating molecule in innate and adaptive responses, thus contributing to anti-tumor immune mediated responses. In addition, members of the IL-1 system act as regulators of mechanisms involved in cancer, including emergency hematopoiesis, trained immunity, and metabolism. Here, we will provide an overview of the IL-1 system in cancer and discuss the functional complexity of IL-1 family cytokines, which orchestrate both protective and pro-tumorigenic responses, by directly acting on cancer cells and by driving environmental stimuli which indirectly act on cancer cells.

Humans