Biology subjects

Carugo, A.

Publications and source records attributed to Carugo, A..

7 recordsLinked to original sources

bioRxiv2024

WRAD core perturbation impairs DNA replication fidelity promoting immunoediting in pancreatic cancer

It is unclear how cells counteract the potentially harmful effects of uncoordinated DNA replication in the context of oncogenic stress. Here, we identify the WRAD (WDR5/RBBP5/ASH2L/DPY30) core as a modulator of DNA replication in pancreatic ductal adenocarcinoma (PDAC) models. Molecular analyses demonstrated that the WRAD core interacts with the replisome complex, with disruption of DPY30 resulting in DNA re-replication, DNA damage, and chromosomal instability (CIN) without affecting cancer cell proliferation. Consequently, in immunocompetent models, DPY30 loss induced T cell infiltration and immune-mediated clearance of highly proliferating cancer cells with complex karyotypes, thus improving anti-tumor efficacy upon anti-PD-1 treatment. In PDAC patients, DPY30 expression was associated with high tumor grade, worse prognosis, and limited response to immune checkpoint blockade. Together, our findings indicate that the WRAD core sustains genome stability and suggest that low intratumor DPY30 levels may identify PDAC patients who will benefit from immune checkpoint inhibitors.

cancer biology↗

bioRxiv2023

Evolutionary fingerprints of EMT in pancreatic cancers

Mesenchymal plasticity has been extensively described in advanced and metastatic epithelial cancers; however, its functional role in malignant progression, metastatic dissemination and therapy response is controversial. More importantly, the role of epithelial mesenchymal transition (EMT) and cell plasticity in tumor heterogeneity, clonal selection and clonal evolution is poorly understood. Functionally, our work clarifies the contribution of EMT to malignant progression and metastasis in pancreatic cancer. We leveraged ad hoc somatic mosaic genome engineering, lineage tracing and ablation technologies and dynamic genetic reporters to trace and ablate tumor-specific lineages along the phenotypic spectrum of epithelial to mesenchymal plasticity. The experimental evidences clarify the essential contribution of mesenchymal lineages to pancreatic cancer evolution and metastatic dissemination. Spatial genomic analysis combined with single cell transcriptomic and epigenomic profiling of epithelial and mesenchymal lineages reveals that EMT promotes with the emergence of chromosomal instability (CIN). Specifically tumor lineages with mesenchymal features display highly conserved patterns of genomic evolution including complex structural genomic rearrangements and chromotriptic events. Genetic ablation of mesenchymal lineages robustly abolished these mutational processes and evolutionary patterns, as confirmed by cross species analysis of pancreatic and other human epithelial cancers. Mechanistically, we discovered that malignant cells with mesenchymal features display increased chromatin accessibility, particularly in the pericentromeric and centromeric regions, which in turn results in delayed mitosis and catastrophic cell division. Therefore, EMT favors the emergence of high-fitness tumor cells, strongly supporting the concept of a cell-state, lineage-restricted patterns of evolution, where cancer cell sub-clonal speciation is propagated to progenies only through restricted functional compartments. Restraining those evolutionary routes through genetic ablation of clones capable of mesenchymal plasticity and extinction of the derived lineages completely abrogates the malignant potential of one of the most aggressive form of human cancer.

cancer biology↗

bioRxiv2021

Targeting glucose metabolism sensitizes pancreatic cancer to MEK inhibition

Pancreatic ductal adenocarcinoma (PDAC) is almost universally lethal. A critical unmet need exists to explore essential susceptibilities in PDAC and identify druggable targets for tumor maintenance. This is especially challenging in the context of PDAC, in which activating mutations of KRAS oncogene (KRAS*) dominate the genetic landscape. By using an inducible KrasG12D-driven p53 deficient PDAC mouse model (iKras model), we demonstrate that RAF-MEK-MAPK signaling is the major effector for oncogenic Kras-mediated tumor maintenance. However, MEK inhibition has minimal therapeutic effect as single agent for PDAC both in vitro and in vivo. Although MEK inhibition partially downregulates the transcription of glycolysis genes, it surprisingly fails to suppress the glycolysis flux in PDAC cell, which is a major metabolism effector of oncogenic KRAS. Accordingly, In vivo genetic screen identified multiple glycolysis genes as potential targets that may sensitize tumor cells to MAPK inhibition. Furthermore, inhibition of glucose metabolism with low dose 2-deoxyglucose (2DG) in combination with MEK inhibitor dramatically induces apoptosis in KrasG12D-driven PDAC cell in vitro, inhibits xenograft tumor growth and prolongs the overall survival of genetically engineered mouse PDAC model. Molecular and metabolism analyses indicate that co-targeting glycolysis and MAPK signaling results in apoptosis via induction of lethal ER stress. Together, our work suggests that combinatory inhibition of glycolysis and MAPK pathway may serve as an alternative approach to target KRAS-driven PDAC.

cancer biology↗

bioRxiv2020

9p21 Loss Defines the Evolutionary Patterns of Aggressive Renal Cell Carcinomas

Dedifferentiation and acquisition of chromosomal instability in renal cell carcinoma portends dismal prognosis and aggressive clinical behavior. However, the absence of reliable experimental models dramatically impacts the understanding of mechanisms underlying malignant progression. Here we established an in vivo genetic platform to rapidly generate somatic mosaic genetically engineerd immune-competent mouse models of renal tumors, recapitulating the genomic and phenotypic features of these malignancies. Leveraging somatic chromosomal engineering, we demonstrated that ablation of the murine locus syntenic to human 9p21 drives the rapid expansion of aggressive mesenchymal clones with prominent metastatic behavior, characterized by early emergence of chromosomal instability, whole-genome duplication, and conserved patterns of aneuploidy. This model of punctuated equilibrium provides a remarkable example of cross-species convergent evolution. SignificanceTo better understand the role of 9p21 in malignant progression, we generated a somatic mosaic GEMM of renal cancer, capturing the histological, genomic and evolutionary features of human disease. With this technology we demonstrated a critica role of 9p21 loss in metastatic evolution of RCC and provide a unique tool for testing new therapeutic treatments.

cancer biology↗

bioRxiv2020

Medium-chain acyl-CoA dehydrogenase, a gatekeeper of mitochondrial function in glioblastoma multiforme

Glioblastoma (GBM) is among the deadliest of human cancers. Despite extensive efforts, it has proven to be highly resistant to chemo- and immune-based therapeutic strategies, and little headway has been made with targeted inhibitors. Like many cancers, metabolism is dysregulated in GBM. Thus, to identify new vulnerabilities and drug targets in GBM, we conducted genetic screens using pooled RNAi libraries targeting metabolic enzymes. We screened multiple glioma stem cell-derived (GSC) xenograft models, which revealed that several enzymes involved in the mitochondrial metabolism of fatty acids were required for tumor cell proliferation. From among these, we focused on medium-chain acyl-CoA dehydrogenase (MCAD), which oxidizes medium-chain fatty acids, due to its consistently high score across all of our screens, as well as its high expression level in multiple GSC models and its upregulation in GBM compared to normal brain. In this manuscript, we describe the dependence of GBM on sustained fatty acid metabolism to actively catabolize lipid species that would otherwise damage the mitochondrial structure. The uptake of mediumchain fatty acids lacks negative feedback regulation; therefore, in the absence of MCAD, medium-chain fatty acids accumulate to toxic levels, inducing reactive oxygen species (ROS), mitochondrial damage and failure, and apoptosis. Taken together, our findings uncover a previously unappreciated protective role exerted by MCAD in GBM cells, making it a unique and therapeutically exploitable vulnerability.

cancer biology↗

bioRxiv2020

Diversity Across the Pancreatic Ductal Adenocarcinoma Disease Spectrum Revealed by Network-Anchored Functional Genomics

Cancers are highly complex ecosystems composed of molecularly distinct sub-populations of tumor cells, each exhibiting a unique spectrum of genetic features and phenotypes, and embedded within a complex organ context. To substantially improve clinical outcomes, there is a need to comprehensively define inter- and intra-tumor phenotypic diversity, as well as to understand the genetic dependencies that underlie discrete molecular subpopulations. To this end, we integrated CRISPR-based co-dependency annotations with a tissue-specific co-expression network developed from patient-derived models to establish CoDEX, a framework to quantitatively associate gene-cluster patterns with genetic vulnerabilities in pancreatic ductal adenocarcinoma (PDAC). Using CoDEX, we defined multiple prominent anticorrelated gene-cluster signatures and specific pathway dependencies, both across genetically distinct PDAC models and intratumorally at the single-cell level. Of these, one differential signature recapitulated the characteristics of classical and basal-like PDAC molecular subtypes on a continuous scale. Anchoring genetic dependencies identified through functional genomics within the gene-cluster signature defined fundamental vulnerabilities associated with transcriptomic signatures of PDAC subtypes. Subtype-associated dependencies were validated by feature-barcoded CRISPR knockout of prioritized basal-like-associated genetic vulnerabilities (SMAD4, ILK, and ZEB1) followed by scRNAseq in multiple PDAC models. Silencing of these genes resulted in a significant and directional clonal shift toward the classical-like signature of more indolent tumors. These results validate CoDEX as a novel, quantitative approach to identify specific genetic dependencies within defined molecular contexts that may guide clinical positioning of targeted therapeutics.

cancer biology↗

bioRxiv2018

WDR5 regulates epithelial-to-mesenchymal transition in breast cancer cells via TGFB

Even if the mortality rate in breast cancer (BC) has recently decreased, development of metastases and drug resistance are still challenges to successful systemic treatment. The epithelial-to-mesenchymal transition (EMT), as well as epigenetic dynamic modifications, plays a pivotal role in invasion, metastasis, and drug resistance. Here, we report that WDR5, the core subunit of histone H3 K4 methyltransferase complexes, is crucial in coordinating EMT and regulating epigenetic changes that drive metastasis. We show that silencing of WDR5 in BC up-regulates an epithelial signature in triple negative and luminal B like patients by transcriptional repression of mesenchymal genes and reduction of the metastatic properties of these cells. Moreover, we demonstrate that this regulation is mediated by inhibition of the TGF{beta} signaling both at the transcriptional and post-translational level, suggesting an active role of WDR5 in guiding tumor plasticity upon oncogenic insults, regardless of the pathological BC subtypes.\n\nWe therefore suggest that WDR5 inhibition could be a successful pharmacologic approach to inhibit EMT and sensitize breast cancer cells to chemotherapy.

cancer biology↗