Search bioRxiv⌕ Search

SEARCH · Search bioRxiv

Results for “Cancer Biology”

Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 649 records · Page 36Linked to original sources

Persistent Post-Inflammatory Matrix Stiffening Defines a Premalignant Mechanical Niche in Ulcerative Colitis-Associated Neoplasia

Patients with long-standing ulcerative colitis (UC) remain at risk for colorectal neoplasia even after overt inflammatory activity improves, suggesting that repaired mucosa may retain residual tissue-level abnormalities. Whether extracellular matrix remodeling leaves a persistent mechanical cue that contributes to early neoplastic remodeling is unknown. Here we identify post-inflammatory matrix stiffening as a premalignant mechanical niche in UC-associated neoplasia. In human colonic biopsies, collagen remodeling and atomic-force-microscopy-based mucosal stiffness increased from non-UC controls to UC and UC-associated dysplasia. A stiffness-associated transcriptional program was also enriched in histologically non-dysplastic mucosa from patients with UC-associated neoplasia. In mouse models, colonic stiffness increased along the colitis-to-tumorigenesis axis and remained elevated during apparent recovery, when epithelial permeability, junctional protein loss, crypt proliferation and nuclear {beta}-catenin accumulation persisted despite reduced disease activity. Stiffness-controlled intestinal epithelial cultures showed that stiff substrates were sufficient to disrupt ZO-1 organization and enhance {beta}-catenin redistribution, particularly under TNF- stimulation. Pharmacological matrix normalization with {beta}-aminopropionitrile partially restored barrier organization and attenuated early epithelial remodeling in vivo. Single-cell profiling identified a stiffness-associated MMP7-positive/YAP-active epithelial state that was enriched in collagen-rich regions and reduced after matrix softening. Inhibition of YAP or MMP7 attenuated stiffness-associated junctional disruption and {beta}-catenin redistribution. These findings suggest that inflammatory recovery and mechanical recovery can be uncoupled, and that persistent mucosal stiffening provides a tissue-level mechanism by which chronically injured UC mucosa may remain biologically vulnerable to premalignant epithelial remodeling.

Cancer Biology↗

The biomedical sensor Cell-Fit-HD4D, reveals individual tumor cell fate in response to microscopic ion deposition.

Here we present the biomedical sensor cell-fluorescent ion track hybrid detector4D (Cell-Fit-HD4D) to reveal individual tumor cell fate in response to microscopic ion deposition in ion beam therapy. The sensor enables long-term monitoring of single tumor cells after clinical ion beam irradiation in combination with single-cell dosimetry. Cell-Fit-HD4D is read out in-situ by conventional optical microscopy. Direct visualization of a clinical ion beam is hereby possible for the first time. The possibility to reveal fate of individual cells from a cell cohort demonstrates that our biomedical sensor clearly differs from conventional experiments that characterize cellular response after radiation on a population level. Cell-Fit-HD4D is therefore used to mimics the clinical situation of a defined tumor depth during tumor treatment by ion beam therapy. Our biomedical sensor is able to provide crucial input for current mechanistic approaches to biophysical modelling of the effect of ionizing radiation on biological matter. In the clinical context, obtaining multi-dimensional physical and biological information on individual tumor cells is an important step to further transform ion beam therapy into a highly precise discipline within oncology.

cancer biology↗

Secreted autotaxin through LPA suppresses chemotaxis and tumor infiltration of CD8+ T Cells

Autotaxin (ATX) is secreted by diverse cell types to produce lysophosphatidic acid (LPA) that regulates multiple biological functions via G protein-coupled receptors LPAR1-6. ATX/LPA promotes tumor cell migration and metastasis mainly via LPAR1; however, its actions in the tumor immune microenvironment remain unclear. Here, we show that ATX secreted by melanoma cells is chemorepulsive for tumor-infiltrating lymphocytes and circulating CD8+ T cells ex vivo, with ATX functioning as an LPA-producing chaperone. Mechanistically, T-cell repulsion predominantly involves G12/13-coupled LPAR6. Upon anti-cancer vaccination of tumor-bearing mice, ATX does not affect the induction of systemic T-cell responses but suppresses tumor infiltration of cytotoxic CD8+ T cells and thereby impairs tumor regression. Moreover, single-cell data from patient samples are consistent with intra-tumor ATX acting as a T-cell repellent. These studies highlight an unexpected role for the pro-metastatic ATX-LPAR axis in suppressing CD8+ T-cell infiltration to impede anti-tumor immunity, suggesting new therapeutic opportunities.

cancer biology↗

In silico reconstruction of primary and metastatic tumor architecture using GIS-augmented spatial transcriptomics

The tumor microenvironment (TME) comprises different cell populations that interact, contributing to tumor heterogeneity and therapy response. Spatial transcriptomics offers valuable insights into transcriptional complexity and heterogeneity of the TME. We established Geographic Information System (GIS)-augmented In-Silico Reconstruction of Tumor Architecture (GIS-ROTA), a biologically informed analytic framework that integrates pathway or cell type-based enrichment analysis with local Morans I to uncover functional spatial domains. In our Visium dataset of primary and metastatic estrogen receptor-positive breast tumor samples, GIS-ROTA revealed extensive co-localization of estrogen response with metabolic pathway gene sets and mutual exclusivity with metastasis-related and specific immune-related pathway gene sets. The novelty of our approach lies in considering biological functions prior to identifying any spatial domains, providing direct interpretability and minimizing the subjectivity of interpreting clusters observed from conventional analytic methods. Overall, our GIS-ROTA framework integrates biological knowledge first, yielding spatial patterns with functional relevance and enabling identification of novel targets for development of therapeutic strategies.

cancer biology↗

Collective radioresistance of T47D breast carcinoma cells is mediated by a Syncytin-1 homologous protein

It is generally accepted that radiotherapy must target clonogenic cells, i.e., those cells in a tumour that have self-renewing potential. Focussing on isolated clonogenic cells, however, may lead to an underestimate or even to an outright neglect of the importance of biological mechanisms that regulate tumour cell sensitivity to radiation. We develop a new statistical and experimental approach to quantify the effects of radiation on cell populations as a whole. In our experiments, we change the proximity relationships of the cells by culturing them in wells with different shapes, and we find that the radiosensitivity of T47D human breast carcinoma cells in tight clusters is different from that of isolated cells. Molecular analyses show that T47D cells express a Syncytin-1 homologous protein (SyHP). We observe that SyHP translocates to the external surface of the plasma membrane of cells killed by radiation treatment. The data support the fundamental role of SyHP in the formation of intercellular cytoplasmic bridges and in the enhanced radioresistance of surviving cells. We conclude that complex and unexpected biological mechanisms of tumour radioresistance take place at the cell population level. These mechanisms may significantly bias our estimates of the radiosensitivity of breast carcinomas in vivo and thereby affect treatment plans, and they call for further investigations.

cancer biology↗

FMAGJ: Fluorescence Microscopic Astrocyte Gap Junction Images Dataset

This work introduces a novel and specialized dataset of high-resolution fluorescence microscopic images focused on astrocytic gap junctions, aiming to get insights into intercellular communication in both healthy and pathological brain conditions. The dataset includes 20 z-stack image series--10 from human glioblastoma tissue and 10 from healthy rat brain tissue--each containing between 22 and 104 optical slices. These images were acquired using standardized protocols following immunofluorescence labeling with antibodies against connexin 43 (Cx43), enabling visualization of gap junction localization at the subcellular level. The dataset is tailored to support detailed morphological and quantitative analyses of gap junction networks, featuring metadata including species and localization of possible gap junctions in images provided by bounding boxes and image masks. Its structure facilitates comparative studies across physiological states and species, enhancing translational and evolutionary perspectives on astrocytic connectivity. Given the labor-intensive nature of manual gap junction quantification, this dataset serves as a resource for the development of machine learning tools capable of automating the detection and analysis of Cx43-positive signals. CCS CONCEPTSComputing methologies[~]Computer vision problems[~]Object detection * Applied computing[~]Life and medical sciences[~]Computational biology/Molecular structural biology * Software and its engineering[~]Software notations and tools[~]Software libraries and repositories

cancer biology↗

Spatial mapping of pediatric brain tumors across diagnoses and relapses

We present a spatial transcriptomic atlas of 19 pediatric brain tumor patients spanning nine major and rare diagnoses, including seven relapses, revealing their spatial cellular and molecular organization. Each tumor section resolves into 2 - 4 recurrent spatial archetypes across 11 biological themes, with some mirroring developmental lineage patterns - for example, oligodendrocyte-lineage programs in pilocytic astrocytomas. Spatially inferred copy-number analysis identifies relapse-associated putative clones. In one rare embryonal tumor, spatial niches in the primary tumor harboring putative clones colocalized with an archetype enriched for nervous system development and glioblast-lineage programs. In one ependymoma and one pilocytic astrocytoma, relapse-associated putative clones preferentially localized to the vasculature, suggesting regrowth during relapse may be seeded by clonal selection of residual tumor cells within specialized microenvironmental niches. This resource provides an open-access spatially resolved map via an interactive viewer to inform research on pediatric brain tumor ecosystems, relapse biology, and therapeutic strategies.

cancer biology↗

Novel BRAF gene fusions in pediatric histiocytic neoplasms define distinct therapeutic responsiveness to RAF paradox breakers

Pediatric histiocytic neoplasms are clonal hematopoietic disorders driven by mutations activating the mitogen-activated protein kinase (MAPK) pathway, such as BRAF-V600E. In non-BRAFV600E cases, we investigated alternative MAPK mutations and found two novel BRAF gene fusions. We investigated the distinct responsiveness of novel BRAF fusions to RAFi therapies and explored the mechanistic basis of such differential responses compared to other BRAF fusions. Two histiocytic patient tumors were analyzed using the CHOP Comprehensive Next-Gen Sequencing Solid Tumor Panel and a targeted RNA-seq panel for 106 fusion partner genes. In the two M- and L-type histiocytic neoplasms assessed, we found novel and rare BRAF gene fusions, MTAP-BRAF and MS4A6A-BRAF, respectively. Both BRAF fusions activated the MAPK/ PI3K pathways and showed homo- and hetero-dimerization with BRAF and the respective N-terminal fusion partner. In contrast to common BRAF fusions, MTAP-BRAF and MS4A6A-BRAF did not respond to PLX8394 due to a lack of disruption of active fusion homo- and hetero-dimers, which was in turn due to the untargeted, stable dimerization mediated by the N-terminal fusion partners. Conversely, we observed robust suppression with LY3009120 that bound fusion dimers and kept them in an inactivate confirmation. MEKi were found to successfully suppress fusion driven signaling and oncogenic phenotypes. Our finding that PLX8394 does not disrupt MTAP-BRAF or MS4A6A-BRAF dimerization due to contribution of N-terminal partners defines a novel paradigm for the distinct mechanisms sought by BRAF fusions in response to RAFi therapy. Overall, this study highlights the unique and differential biology hijacked by BRAF fusions in response to RAFi and further warrants detailed mechanistic classification of BRAF fusions based on their responsiveness to targeted agents.

cancer biology↗

Gain-of-function CRISPR screens identify tumor-promoting genes conferring melanoma cell plasticity and therapy-resistance

Most genetic alterations that drive melanoma development and resistance to targeted therapy have been uncovered. In contrast, and despite their increasingly recognized contribution, little is known about the non-genetic mechanisms that drive these processes. Here, we performed in vivo gain-of-function CRISPR screens and identified SMAD3, BIRC3 and SLC9A5 as key actors of BRAFi-resistance and these genes promote the tumor growth capability of persister cells. We show that their expression levels increase during acquisition of BRAFi-resistance, and remain high in persister cells and during relapse. The upregulation of the SMAD3 transcriptional activity (SMAD3-signature) promotes a mesenchymal-like phenotype and BRAFi-resistance by acting as an upstream transcriptional regulator of potent BRAFi-resistance genes such as EGFR and AXL. This SMAD3-signature predicts resistance to both current melanoma therapies in different cohorts. Critically, chemical inhibition of SMAD3 may constitute amenable target for melanoma since it efficiently abrogates persister cells survival. Interestingly, decrease of SMAD3 activity can also be reached by inhibiting the aryl hydrocarbon receptor (AhR), another druggable transcription factor governing SMAD3 expression level. Our work expands our understanding of the biology of persister cells and highlight novel drug vulnerabilities that can be exploited to develop long-lasting antimelanoma therapies.

cancer biology↗

Single Nuclei Sequencing Reveals Replication Stress in Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a poor prognosis and limited treatment options. Bulk genomic characterization of ACC has not yielded obvious therapeutic or immunotherapeutic targets, yet novel therapies are needed. We hypothesized that elucidating the intratumoral cellular heterogeneity by single nuclei RNA sequencing analyses would yield insights into potential therapeutic vulnerabilities of this disease. In addition to characterizing the immune cell and fibroblast landscape, our analyses of single nuclei gene expression profiles identified an adrenal cortex cell cluster exhibiting a program of replication stress and DNA damage response in primary and metastatic ACC. In vitro assessment of replication stress and DNA damage response using an ACC cell line and a series of newly-derived hormonally active patient-derived tumor organoids revealed ATR sensitivity. These findings provide novel mechanistic insight into ACC biology and suggest that an underlying dependency on ATR may be leveraged therapeutically in advanced ACC.

cancer biology↗

Clinically Important sex differences in GBM biology revealed by analysis of male and female imaging, transcriptome and survival data

Sex differences in the incidence and outcome of human disease are broadly recognized but in most cases not adequately understood to enable sex-specific approaches to treatment. Glioblastoma (GBM), the most common malignant brain tumor, provides a case in point. Despite well-established differences in incidence, and emerging indications of differences in outcome, there are few insights that distinguish male and female GBM at the molecular level, or allow specific targeting of these biological differences. Here, using a quantitative imaging-based measure of response, we found that temozolomide chemotherapy is more effective in female compared to male GBM patients. We then applied a novel computational algorithm to linked GBM transcriptome and outcome data, and identified novel sex-specific molecular subtypes of GBM in which cell cycle and integrin signaling were identified as the critical determinants of survival for male and female patients, respectively. The clinical utility of cell cycle and integrin signaling pathway signatures was further established through correlations between gene expression and in vitro chemotherapy sensitivity in a panel of male and female patient-derived GBM cell lines. Together these results suggest that greater precision in GBM molecular subtyping can be achieved through sex-specific analyses, and that improved outcome for all patients might be accomplished via tailoring treatment to sex differences in molecular mechanisms.\n\nOne Sentence SummaryMale and female glioblastoma are biologically distinct and maximal chances for cure may require sex-specific approaches to treatment.

cancer biology↗

Multi-hit STAG2 mutations define a high-risk subset of MDS and reveal convergent evolutionary targeting of cohesin

STAG2 is the most frequently mutated cohesin gene in myeloid neoplasms, yet the significance of multiple mutations within this X-linked tumor suppressor remains unknown. We analyzed a cohort of 1,967 adult patients with myeloid neoplasms and identified 233 cases (12%) harboring STAG2 mutations, including 38 cases (16%) with multiple STAG2 hits. Patients with multi-hit STAG2 mutations exhibited increased multilineage dysplasia compared with single-hit cases and experienced inferior overall survival, an effect driven primarily by patients with myelodysplastic syndromes (MDS). To investigate the molecular basis of recurrent STAG2 acquisition, we performed long-read sequencing in representative cases with phaseable STAG2 mutations. In the informative case examined, distinct truncating STAG2 mutations did not co-occur on the same DNA molecule, supporting independent acquisition rather than stepwise allelic inactivation. Cohort-level variant allele frequency patterns were consistent with recurrent evolutionary targeting of STAG2 across related clonal populations. Together, these findings support a model in which multi-hit STAG2 mutations arise through convergent evolution and define a biologically distinct, adverse-risk subset of MDS.

cancer biology↗

Dysregulation of the p16-CDK6 axis characterizes HPV-unrelated p16-positive oropharyngeal carcinoma

Human papillomavirus (HPV)-related and HPV-unrelated oropharyngeal squamous cell carcinomas (OPCs) are distinct entities with different clinical outcomes. While p16 immunohistochemistry (IHC) is widely used as a surrogate marker for HPV-driven OPC, a subset of HPV-unrelated OPCs also overexpress p16, and the biological basis of this discordance remains unclear. Here, we performed integrated clinicopathological, transcriptomic, genomic, and functional analyses of OPCs and demonstrated that dysregulation of the p16-CDK6 axis characterizes HPV-unrelated p16-positive OPCs. Although these tumors closely resembled HPV-unrelated p16-negative OPCs in their clinicopathological and transcriptomic characteristics, they exhibited a more favorable prognosis. CDK6 was recurrently upregulated in HPV-unrelated OPC regardless of p16 status and was already detectable in high-grade dysplastic leukoplakia, suggesting that CDK6 activation is an early event in HPV-unrelated tumorigenesis. In experimental models, CDK6 overexpression induced compensatory p16 upregulation, creating selective pressure for subsequent CDKN2A inactivation. Consistent with this model, homozygous CDKN2A loss predominated in p16-negative tumors. We further identified CDKN2A frameshift mutations generating p14ARF-p16 chimeric proteins that retain p16 immunoreactivity despite functional loss of wild-type p16, revealing a previously unrecognized diagnostic pitfall of p16 IHC. These findings provide a biological framework for p16 overexpression in HPV-unrelated OPC and suggest that assessment of the p16-CDK6 axis may refine molecular classification and risk stratification beyond p16 IHC alone.

cancer biology↗

Bringing the pancreas patient back to the bench: Ex vivo culture of intact human patient derived pancreatic tumour tissue

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is attributed to the highly fibrotic stroma and complex multi-cellular microenvironment that is difficult to fully recapitulate in pre-clinical human models. To fast-track translation of therapies and to inform personalised medicine, we aimed to develop a whole-tissue ex vivo explant model that maintains viability, 3D multicellular architecture, and microenvironmental cues present in human pancreatic tumours. Patient-derived surgically-resected PDAC tissue was cut into 2 mm explants, cultured on gelatin sponges, and grown for 12 days. Immunohistochemistry revealed that human PDAC tissue explants were viable for 12 days and maintained their original tumour, stromal and extracellular matrix architecture. As proof-of-principle, human PDAC tissue explants responded to Abraxane(R) treatment with a 3.7-fold increase in cell-death (p=0.0007). PDAC explants were also transfected with polymeric nanoparticles+Cy5-siRNA and we observed abundant cytoplasmic distribution of nanoparticle+Cy5-siRNA throughout the PDAC explant tissue. Our novel model retains the 3D architecture of human pancreatic tumours and has several advantages over standard organoids: presence of functional multi-cellular stroma and fibrosis and no tissue manipulation, digestion, or artificial propagation of organoids. This provides an unprecedented opportunity to study PDAC biology, tumour-stromal interactions and rapidly assess therapeutic response that could drive personalised treatment for PDAC.

cancer biology↗

Self-supervised AI reveals a lethal discohesive phenotype in lung adenocarcinoma

Applications of artificial intelligence (AI) to histopathology are now common, but most require supervision which inherently limits their scope. By using self-supervised learning (SSL), we discover and quantify the full range of histopathological appearances in a disease, and associate them with clinicopathological ground truths such as prognosis. We used this approach to discover under-appreciated morphologies of lung adenocarcinoma (LUAD), using a highly characterised resected tumour cohort of over 4000 slides from over 1000 patients. By constructing an authoritative lexicon of recurrent LUAD appearances, we ab initio discovered several stromal morphologies strongly predictive of outcome. With multimodal data integration and external dataset validation, we propose that epithelial discohesion is lethal, but only in the context of immunologically cold stroma. Both these morphological features are independent of current prognostic schema. Crucially, we describe these features in the context of real-world diagnostic histopathology, giving them immediate clinical translatability. Statement of SignificanceHistopathology relies heavily on epithelial morphology, often neglecting the stroma. We use self-supervised AI to identify under-appreciated morphologies in LUAD linked to poor outcome and validate these observations in an external cohort, demonstrating the utility of self-supervised AI as a powerful biological discovery tool.

cancer biology↗

The BLIMP1 - EZH2 nexus in a non-Hodgkin lymphoma

Waldenstroms macroglobulinemia (WM) is a non-Hodgkin lymphoma, resulting in antibody-secreting lymphoplasmacytic cells in the bone marrow and pathologies resulting from high levels of monoclonal immunoglobulin M (IgM) in the blood. Despite the key role for BLIMP1 in plasma cell maturation and antibody secretion, its potential role in WM cell biology has not yet been explored. Here we provide evidence of a crucial role for BLIMP1 in the survival of WM cells and further demonstrate that BLIMP1 is necessary for the expression of the histone methyltransferase EZH2 in both WM and multiple myeloma. The effect of BLIMP1 on EZH2 levels is post translational, at least partially through the regulation of proteasomal targeting of EZH2. Chromatin immunoprecipitation analysis and transcriptome profiling suggest that the two factors co-operate in regulating genes involved in cancer cell immune evasion. Co-cultures of natural killer cells and WM cells further reveal that both factors participate directly in immune evasion, promoting escape from natural killer cell mediated cytotoxicity. Together, the interplay of BLIMP1 and EZH2 plays a vital role in promoting the survival of WM cells.

cancer biology↗

Melanoma proteomics unravels major differences related to mutational status

The aim of the study was to explore the molecular differences between melanoma tumor subtypes, based on BRAF and NRAS mutational status. Fourteen formalin-fixed, paraffin- embedded melanoma samples were analyzed using a high-throughput proteomics approach, coupled with probabilistic graphical models and Flux Balance Analysis, to characterize these differences. Proteomics analyses showed differences in expression of proteins related with fatty acid metabolism, melanogenesis and extracellular space between BRAF mutated and BRAF non-mutated melanoma tumors. Additionally, probabilistic graphical models showed differences between melanoma subgroups at biological processes such as melanogenesis or metabolism. On the other hand, Flux Balance Analysis predicts a higher tumor growth rate in BRAF mutated melanoma samples. In conclusion, differential biological processes between melanomas showing a specific mutational status can be detected using combined proteomics and computational approaches.

cancer biology↗

Phosphoproteomic Landscape of AML Cells Treated with the ATP-Competitive CK2 Inhibitor CX-4945

Casein kinase 2 (CK2) regulates a plethora of proteins with pivotal roles in solid and hematological neoplasia. Particularly, in acute myeloid leukemia (AML) CK2 has been pointed as an attractive therapeutic target and prognostic marker. Here, we explored the impact of CK2 inhibition over the phosphoproteome of two cell lines representing major AML subtypes. Quantitative phosphoproteomic analysis was conducted to evaluate changes in phosphorylation levels after incubation with the ATP-competitive CK2 inhibitor CX-4945. Functional enrichment, network analysis, and database mining were performed to identify biological processes, signaling pathways, and CK2 substrates that are responsive to CX-4945. A total of 273 and 1310 phosphopeptides were found differentially modulated in HL-60 and OCI-AML3 cells, respectively. Despite regulated phosphopeptides belong to proteins involved in multiple biological processes and signaling pathways, most of these perturbations can be explain by direct CK2 inhibition rather than off-target effects. Furthermore, CK2 substrates regulated by CX-4945 are mainly related to mRNA processing, translation, DNA repair, and cell cycle. Overall, we evidenced that CK2 inhibitor CX-4945 impinge on mediators of signaling pathways and biological processes essential for primary AML cells survival and chemosensitivity, reinforcing the rationale behind the pharmacologic blockade of protein kinase CK2 for AML targeted therapy.

cancer biology↗