Biology subjects

Will, R.

Publications and source records attributed to Will, R..

9 recordsLinked to original sources

bioRxiv2025

GLYATL1 is associated with metabolic and epigenetic changes and with endocrine resistance in luminal breast cancer

Estrogen receptor alpha (ER)-positive luminal breast cancer is commonly treated with aromatase inhibitors (AI) to block estrogen signaling; however, resistance frequently develops, limiting therapy success. We observed that GLYATL1 (Glycine-N-Acyltransferase Like 1) expression is upregulated in AI-resistant breast cancer cell models and in patients undergoing AI therapy, correlating with poorer survival. Here we demonstrate that GLYATL1 promotes resistance to estrogen deprivation by elevating succinate levels and altering epigenetic histone marks associated with active transcription. Knockdown or knockout of GLYATL1 reverses these effects and reduces proliferation under estrogen-deprived conditions. Notably, GLYATL1 expression is positively regulated by estrogen receptor alpha signaling independently of estrogen. These findings reveal GLYATL1 as a metabolic and epigenetic mediator of endocrine therapy resistance, suggesting it as a potential target to overcome AI resistance in luminal breast cancer.

cancer biology↗

bioRxiv2025

Exploration of oncogenic cooperation between germline variation and somatic mutation in prostate cancer progression

Prostate carcinoma (PCa) is the most common cancer of men, associated with a still unresolved issue of accurate risk-stratification. While recent advances in omics technologies have provided clues as to how molecular changes shape the onset and progression of PCa, it remains largely unclear whether germline variants and somatic mutations cooperate to contribute to PCa progression and outcome. Thus, we explored whether oncogenic cooperation between regulatory germline variants and somatic driver mutations can help explain why some PCa patients develop a more aggressive phenotype, which may have implications for risk-adapted medical treatment. Here, by employing an integrative functional genomics approach, we identified receptor-type protein-tyrosine phosphatase kappa (PTPRK) as a TMPRSS2::ERG (TE)-modulated gene associated with PCa progression whose expression is controlled by cooperation of the TE-fusion with a regulatory single nucleotide polymorphism (SNP). Analysis of available clinically annotated patient cohorts demonstrated that PTPRK is overexpressed in TE-positive PCa tumors and associated with higher Gleason scores and metastatic disease. TE knockdown in PCa cell lines reduced PTPRK expression, while ectopic overexpression of the fusion in TE-negative PCa cell lines and prostatic epithelium cells induced its expression. Functionally, PTPRK silencing inhibited cellular proliferation, cell cycle progression, and clonogenic growth of PCa cells, which was mirrored by dysregulation of corresponding gene and protein signatures in global transcriptomic and phospho-proteomic analyses after PTPRK knockdown. Analysis of TE ChIP-Seq and Hi-C data from PCa cells highlighted a proximal TE-bound DNA element whose TE-dependent enhancer activity was validated in reporter assays and which could be abrogated by a regulatory SNP. Collectively, our results provide evidence of how exploration of oncogenic cooperation may help to identify novel biomarkers and potentially druggable pathways and highlight the role of the regulatory genome in PCa progression.

cancer biology↗

bioRxiv2024

Loss of SMARCB1 evokes targetable epigenetic vulnerabilities in Epithelioid Sarcoma

Dysfunction of epigenetic modulators, such as the SWI/SNF complex, is a wide-spread but relatively ill-defined feature of a broad spectrum of cancer entities. Among SWI/SNF-mutant entities, SMARCB1-deficient cancers, such as the highly aggressive Epithelioid Sarcoma (EpS), are characterized by this genetic event in an otherwise rather silent mutational landscape. This renders EpS an ideal model to study how epigenetic reprogramming by a single mutation can contribute to tumorigenesis. Hence, to characterize and compare the function of the SMARCB1-deficient, residual and the physiological SWI/SNF complex in cancer, we generated a panel of SMARCB1 re-expressing EpS cell lines and employed a functional multi-omics approach. Here, we show that SWI/SNF holds canonical characteristics of both tumor-suppressors and proto-oncogenes due to its multi-faceted role in the regulation of the epigenome. Our data indicates that the loss of SMARCB1 causes an overall loss of SWI/SNF chromatin affinity at cis-regulatory enhancer elements, inducing a preference for uncontrolled proliferation and cell cycle progression as opposed to development and differentiation. We further demonstrate that EpS cell lines depend on residual SWI/SNF action to maintain clonogenicity and proliferation. Consequently, EpS cell lines exhibit markedly increased sensitivity to pharmacological inhibition of the residual SWI/SNF when compared with SWI/SNF-proficient cancer entities. Collectively, our results from the EpS model shed new light on how a single mutation can rewire the pleiotropic effects of an epigenetic master regulator and provide inroads for therapeutic intervention.

cancer biology↗

bioRxiv2023

EMP3 sustains oncogenic EGFR/CDK2 signaling by restricting receptor degradation in glioblastoma

Epithelial membrane protein 3 (EMP3) is an N-glycosylated tetraspanin with a putative trafficking function. It is highly expressed in isocitrate dehydrogenase-wild-type glioblastoma (IDH-wt GBM), and its high expression correlates with poor survival. However, the exact trafficking role of EMP3 and how it promotes oncogenic signaling in GBM remain unclear. Here, we show that EMP3 promotes EGFR/CDK2 signaling by regulating the trafficking and enhancing the stability of EGFR. BioID2-based proximity labeling revealed that EMP3 interacts with endocytic proteins involved in the vesicular transport of EGFR. EMP3 knockout (KO) enhances epidermal growth factor (EGF)-induced shuttling of EGFR into RAB7+ late endosomes, thereby promoting EGFR degradation. Increased EGFR degradation is rescued by the RAB7 negative regulator and novel EMP3 interactor TBC1D5. Phosphoproteomic and transcriptomic analyses further showed that EMP3 KO converges into the inhibition of the cyclin-dependent kinase CDK2 and the repression of EGFR-dependent and cell cycle transcriptional programs. Phenotypically, EMP3 KO cells exhibit reduced proliferation rates, blunted mitogenic response to EGF, and increased sensitivity to the pan-kinase inhibitor staurosporine and the EGFR-specific inhibitor osimertinib. Furthermore, EGFR-dependent patient-derived glioblastoma stem cells display increased susceptibility to CDK2 inhibition upon EMP3 knockdown. Lastly, using TCGA data, we showed that GBM tumors with high EMP3 expression have increased total and phosphorylated EGFR levels. Collectively, our findings demonstrate a novel EMP3-dependent mechanism by which EGFR/CDK2 activity is sustained in GBM. Consequently, this stabilizing effect provides an additional layer of tumor cell resistance against targeted kinase inhibition.

cancer biology↗

bioRxiv2022

Chromosome 8 gain drives poor patient outcome via expression of 4E-BP1 in Ewing sarcoma

Chromosome 8 (chr8) gains are common in cancer. However, their potential contribution to tumor heterogeneity is largely unexplored. Ewing sarcoma (EwS) is characterized by pathognomonic FET::ETS fusions but a general paucity of other recurrent somatic mutations that could explain the observed clinical diversity. In EwS, chr8 gains are the second most common genetic alteration rendering EwS an ideal model to investigate the relevance of chr8 gains in an otherwise silent genomic context. Here, we report that chr8 gain-driven gene expression patterns correlate with poor overall survival of EwS patients. This effect is predominantly mediated by increased expression of the translation initiation factor binding protein 4E-BP1 encoded by EIF4EBP1 on chr8. High EIF4EBP1 expression showed the strongest association with poor patient survival among all chr8-encoded genes and correlated with chr8 gains in EwS tumors. Similar findings were made in numerous entities of The Cancer Genome Atlas (TCGA). Integrated multi-omics profiling uncovered that 4E-BP1 orchestrates a pro-proliferative proteomic network. Consistently, silencing of 4E-BP1 in the EwS model reduced cell proliferation, clonogenicity, spheroidal growth in vitro, and tumorigenesis in vivo. Drug screens and functional assays revealed that high 4E-BP1 expression sensitizes for pharmacological CDK4/6 inhibition in preclinical models. Collectively, we establish chr8 gains and high 4E-BP1 expression as prognostic biomarkers in EwS and demonstrate that their association with patient outcome is primarily mediated by 4E-BP1 orchestrating a pro-proliferative proteomic network sensitizing EwS for CDK4/6 inhibitors. Our data suggest that testing for chr8 gains may improve risk-stratification and therapeutic management in EwS and other cancers.

cancer biology↗

bioRxiv2021

A connectivity signature for glioblastoma

Tumor cell extensions called tumor microtubes (TMs) in glioma resemble neurites during neurodevelopment and connect glioma cells to a network that has considerable relevance for tumor progression and therapy resistance. The determination of interconnectivity in individual tumors has been challenging and the impact of tumor cell connectivity on patient survival remained unresolved so far. Here, a connectivity signature from single-cell RNA-sequenced (scRNA-Seq) xenografted primary glioblastoma (GB) cells was established and clinically validated. Thirty-four of 40 connectivity genes were related to neurogenesis, neural tube development or glioma progression, including the TM-network-relevant GAP43 gene. Astrocytic-like and mesenchymal-like GB cells had the highest connectivity signature scores in scRNA-Seq data of patient-derived xenografts and patient samples. In 230 human GBs, high connectivity correlated with the mesenchymal expression subtype, TP53 wildtype, and with dismal patient survival. CHI3L1 was identified as a robust molecular marker of connectivity. Thus, the connectivity signature allows novel insights into brain tumor biology, provides a proof-of-principle that tumor cell connectivity is relevant for patients prognosis, and serves as a robust biomarker that can be used for future clinical trials. Statement of significanceIntegration of GB cells into functional networks drives tumor progression and resistance. Here, we established and validated a novel connectivity gene expression signature of single GB cells and whole tumors that can be easily applied to clinical and preclinical samples. It is shown that connectivity is determining prognosis combining molecular, functional and clinical insights into the disease.

cancer biology↗

bioRxiv2021

Coordinated regulation of WNT/β-catenin, c-Met, and Integrin signalling pathways by miR-193b controls triple negative breast cancer metastatic traits

BackgroundTriple Negative Breast Cancer (TNBC) is the most aggressive subtype of Breast Cancer (BC). Treatment options for TNBC patients are limited and further insights into disease aetiology are needed to develop better therapeutic approaches. microRNAs ability to regulate multiple targets could hold a promising discovery approach to pathways relevant for TNBC aggressiveness. Thus, we address the role of miRNAs in controlling signalling pathways and phenotypes relevant to the biology of TNBC. MethodsTo identify miRNAs regulating WNT/{beta}-catenin, c-Met, and integrin signalling pathways, we performed a high-throughput targeted proteomic approach, investigating the effect of 800 miRNAs on the expression of 62 proteins in the MDA-MB-231 TNBC cell line. We then developed a novel network analysis, Pathway Coregulatory (PC) score, to detect miRNAs regulating the three pathways. Using in vitro assays for cell growth, migration, apoptosis, and stem-cell content, we validated the function of candidate miRNAs. Bioinformatic analyses using BC patients datasets were employed to assess expression of miRNAs as well as their pathological relevance in TNBC patients. ResultsWe identified six candidate miRNAs coordinately regulating the three signalling pathways. Quantifying cell growth of three TNBC cell lines upon miRNA gain-of-function experiments, we characterised miR-193b as a strong and consistent repressor of this phenotype. Importantly, the effects of miR-193b were stronger than chemical inhibition of the individual pathways. We further demonstrated that miR-193b induced apoptosis, repressed migration, and regulated stem-cell markers in MDA-MB-231 cells. Furthermore, miR-193b expression was the lowest in patients classified as TNBC or Basal compared to other subtypes when classified by PAM50 signatures. Gene Set Enrichment Analysis showed that miR-193b expression was significantly associated with reduced activity of of WNT/{beta}-catenin and c-Met signalling pathways in TNBC patients. ConclusionsIntegrating miRNA-mediated effects and protein functions on networks, we show that miRNAs predominantly act in a coordinated fashion to activate or repress signalling pathways responsible for metastatic traits in TNBC. We further demonstrate that our top candidate, miR-193b, regulates these phenotypes to an extent stronger than individual pathway inhibition, thus proving that its effect on TNBC aggressiveness is mediated by repressing multiple interconnected pathways.

cancer biology↗

bioRxiv2020

Reprogramming of stromal fibroblasts by chemotherapy-induced secretion of IFNβ1 drives re-growth of breast cancer cells after treatment.

Chemotherapy is still the standard of care for a large number of aggressive tumours including breast cancer. In breast cancer, chemotherapeutic regimens are administered in intervaled cycles of the maximum tolerated dose, allowing cancer cells to re-grow or adapt during the resting periods between cycles. However, how stromal fibroblasts impact the fate of cancer cells after chemotherapy treatment remains poorly understood. We show that cancer cells utilize paracrine signalling with stromal fibroblasts to drive their recovery after treatment withdrawal. Secretion of IFN{beta}1 by cancer cells after treatment with high doses of chemotherapy instigates the acquisition of an anti-viral state in stromal fibroblasts associated with the expression of several interferon stimulated genes (ISGs), including numerous pro-inflammatory cytokines. This crosstalk is an important driver of the expansion of breast cancer cells after chemotherapy and blocking of IFN{beta}1 in tumour cells abrogated their increased recovery potential. Analysis of human breast carcinomas supports the proposed role of IFN{beta}1 since its expression is inversely correlated with recurrence free survival (RFS). Moreover, expression of the interferon signature identified in stromal fibroblasts is equally associated with higher recurrence rates and a worse outcome in breast cancer patients. Our study unravels a novel paracrine communication between cancer cells and fibroblasts that ultimately results in the escape of malignant cells to treatment. Targeting of this axis could potentially improve the outcome of breast cancer patients to chemotherapy treatment.

cancer biology↗

bioRxiv2020

Time-resolved profiling reveals ATF3 as a novel mediator of endocrine resistance in breast cancer

Breast cancer is one of the leading causes of death for women worldwide. Patients whose tumors express Estrogen Receptor (ER) account for around 70% of cases and are mostly treated with targeted endocrine therapy. However, 40% of these tumors eventually relapse due to resistance development and further treatment of these patients is highly ineffective. In this study we profiled the early phases of the resistance development process to uncover drivers of this phenomenon. Time-resolved analysis revealed that ATF3, a member of the ATF/CREB family of transcription factors, acts as a novel regulator of the response to therapy via rewiring of central signaling processes towards the adaptation to endocrine treatment. ATF3 was found to be essential in controlling crucial processes such as proliferation, cell cycle and apoptosis during the early response to treatment through the regulation of MAPK/AKT signaling pathways. Its essential role was confirmed in vivo in a mouse model and elevated expression of ATF3 was verified in patient datasets, adding clinical relevance to our findings. This study proposes ATF3 as a novel mediator of endocrine resistance development in breast cancer and elucidates its role in the regulation of downstream pathways activities.

cancer biology↗