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Vizeacoumar, F. J.

Publications and source records attributed to Vizeacoumar, F. J..

4 recordsLinked to original sources

Organoid Pharmacotyping of Pancreatic Cancer Enables Functional Precision Oncology and Drug Repurposing

PurposePancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies, with limited benefit from current cytotoxic regimens and poor predictive value of genomics alone. Patient-derived organoids (PDOs) represent a promising platform for functional precision oncology, yet systematic pharmacotyping of genomically annotated PDAC PDOs remains sparse. Experimental DesignWe established a clinically annotated panel of ten treatment-naive PDAC PDOs spanning well-, moderately-, and poorly differentiated tumors. PDOs were evaluated for morphologic and genomic fidelity and screened against 1,813 clinically relevant small molecules in a high-throughput 384-well format. Drug sensitivities were quantified at the compound and drug-family levels and integrated with histologic grade, pathway-level mutational profiles, and available clinical treatment information. ResultsPDOs preserved hallmark tumor features, including glandular organization and subclonal mutational architecture. Pharmacotyping revealed both shared and subtype-specific vulnerabilities. Classical (well/moderately differentiated) PDOs showed enriched mutations in DNA repair, mitotic spindle, and chromatin-regulatory pathways and were preferentially sensitive to topoisomerase inhibitors, microtubule poisons, and HDAC inhibitors. In contrast, basal (poorly differentiated) PDOs displayed coordinated defects in mitochondrial function, vesicle trafficking, and ubiquitin-mediated proteostasis, at the pathway level, that conferred a previously unrecognized vulnerability to cardiac glycosides. Sensitivities to standard PDAC agents were heterogeneous across models, underscoring the limited predictive value of genotype alone and the need for functional drug testing. ConclusionsThis integrated genomic and pharmacologic analysis demonstrates that PDO pharmacotyping identifies biologically grounded, actionable vulnerabilities in PDAC, including novel therapeutic opportunities in basal, chemo-resistant tumors. These findings support PDO-guided functional profiling as a clinically relevant platform for refining drug selection and expanding treatment options for patients with PDAC. SignificancePDAC is dominated by chemoresistance and lacks reliable genomic predictors of therapy response. By integrating high-throughput drug screening with mutation-informed pathway analysis in patient-derived organoids, we identify differentiation-linked therapeutic liabilities, including a previously unrecognized vulnerability to cardiac glycosides in basal PDAC. These results highlight PDO pharmacotyping as a powerful functional complement to genomics for guiding treatment selection in pancreatic cancer.

cancer biology↗

Genome-wide Screening Identifies Unique Host-Directed Drugs and Pro-viral Signalling Pathways for SARS-CoV-2

SARS-CoV-2 is a positive-sense RNA virus and was responsible for the devastating COVID-19 pandemic. Although the current disease burden is less severe, there are limited treatment options, significant gaps in knowledge, and a looming threat of the emergence of variants and future pandemics. To address these challenges, we performed genome-wide CRISPR knockout screens in a novel human lung cell line NCI-H23ACE2, as well as in HEK293TACE2 cells, with SARS-CoV-2 Wuhan virus, with the aim of identifying host-dependency factors that could predict effective antivirals. We identified four host-directed drugs, donepezil, dH-ergocristine, trametinib and sorafenib, that could potentially be repurposed to treat coronavirus infections. Three of the drugs inhibited SARS-CoV-2, HCoV-229E, and HCoV-OC43, suggesting they could be used as pan-coronavirus antivirals. We also confirmed that SARS-CoV-2 relies on the NRAS/Raf/MEK/ERK signaling pathway for its replication. Our study highlights the robustness and efficiency of a bilateral approach of gene silencing and antiviral screening to identify host-dependency factors and effective antivirals.

microbiology↗

Cancer Cell`s Seven Achilles Heels: Consideration for desing of anti-cancer drug combinations.

Loss of function screens using shRNA and CRISPR are routinely used to identify genes that modulate responses of tumor cells to anti-cancer drugs. Here, by integrating GSEA and CMAP analyses of multiple published shRNA screens, we identified a core set of pathways that affect responses to multiple drugs with diverse mechanisms of action. This suggests that these pathways represent "weak points" or "Achilles heels", whose mild disturbance should make cancer cells vulnerable to a variety of treatments. These "weak points" include proteasome, protein synthesis, RNA splicing, RNA synthesis, cell cycle, Akt-mTOR, and tight junction-related pathways. Therefore, inhibitors of these pathways are expected to sensitize cancer cells to a variety of drugs. This hypothesis was tested by analyzing the diversity of drugs that synergize with FDA-approved inhibitors of the proteasome, RNA synthesis, and Akt-mTOR pathways. Indeed, the quantitative evaluation indicates that inhibitors of any of these signaling pathways can synergize with a more diverse set of pharmaceuticals, compared to compounds inhibiting targets distinct from the "weak points" pathways. Our findings described here imply that inhibitors of the "weak points" pathways should be considered as primary candidates in a search for synergistic drug combinations.

cancer biology↗

Expression-based analyses indicate a central role for hypoxia in driving tumor plasticity through microenvironment remodeling and chromosomal instability

Can transcriptomic alterations drive the evolution of tumors? We rationalize that expressional changes found in all patients arise earlier in tumor development compared to alterations that occur only in limited subsets of patients. Our analyses of non-mutated genes from the non-amplified regions of the genome of 158 triple negative breast cancer (TNBC) cases identified 219 exclusively expression-altered (EEA) genes that may play important role in TNBC. Phylogenetic analyses of these genes predict a \"punctuated burst\" of multiple gene up-regulation events occurring at early stages of tumor development, followed by minimal subsequent changes later in tumor progression. Remarkably, this punctuated burst of expressional changes is instigated by hypoxia-related molecular events, predominantly in two groups of genes that control chromosomal instability (CIN) and remodel tumor microenvironment (TME). We conclude that alterations in the transcriptome are not stochastic and that early stage hypoxia induces CIN and TME remodeling to permit further tumor evolution.

cancer biology↗