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Nevot, A.

Publications and source records attributed to Nevot, A..

2 recordsLinked to original sources

A genome-wide CRIPR-Cas9 screen identifies TGN46 as a host determinant for H-1PV susceptibility in pancreatic adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal malignancy with limited response to current therapeutic strategies. Oncolytic viruses such as the rat protoparvovirus H-1PV represent promising alternatives; however, their clinical development is hindered by an incomplete understanding of virus-host interactions that determine tumor susceptibility. Here, we conducted a genome-scale CRISPR-Cas9 knockout screen in primary PDAC cultures to identify host determinants of viral infection and cytotoxicity. The screen confirmed the central role of the sialylation pathway in mediating susceptibility to H-1PV and uncovered several additional genes involved in vesicular trafficking and protein recycling. Among these candidates, TGOLN2, encoding the transmembrane protein TGN46, emerged as a critical host factor. Functional analyses demonstrate that TGN46 supports efficient H-1PV infection, replication, and virus-induced cytotoxicity in pancreatic cancer cells. TGN46 colocalizes with viral particles at the cell surface and facilitates their internalization through dynamin-dependent endocytosis. Molecular studies further indicate that the luminal N-terminal domain of TGN46 interacts with the viral capsid. In vivo, TGOLN2 expression in essential to H-1PV-mediated antitumor activity in experimental models. Collectively, these findings identify TGN46 as a membrane-associated entry factor required for optimal H-1PV infection in PDAC cells. This work refines the mechanistic understanding of H-1PV tropism and provides a rationale for exploring host determinants of viral susceptibility as candidate biomarkers to guide parvovirus-based virotherapy.

cancer biology↗

Cytidine deaminase protects pancreatic cancer cells from replicative stress and drives resistance to DNA-targeting drugs

Chronic DNA replication stress and genome instability are two hallmarks of cancer that fuel oncogenesis and tumor diversity. Therapeutic approaches aimed to leverage tumor-specific replication stress to intolerable levels or to expose vulnerabilities for synthetic lethality purposes have recently gained momentum, especially for pancreatic cancer, a disease with no cure. However, the current knowledge regarding the molecular mechanisms involved in the replication stress response in pancreatic tumors is limited. Cytidine deaminase (CDA) is involved in the pyrimidine salvage pathway for DNA and RNA synthesis. Loss of CDA induces genomic instability in Bloom Syndrome, and CDA protects tumor cells from chemotherapy with pyrimidine analogs. Here, we show that CDA is overexpressed in genetically unstable pancreatic tumors, associates with a DNA replication signature, and is instrumental for experimental tumor growth. In cancer cells, CDA promotes DNA replication, increases replication fork speed, and controls replication stress and genomic stability levels. CDA expression is predictive of DNA-damaging drug efficacy and targeting CDA relieves resistance to chemotherapy in patients models, both in vitro and in vivo. Our findings shed new light on the mechanisms by which pancreatic cancer cells control replication stress, and highlight targeting of CDA as a potential therapeutic strategy to defeat tumor resistance to treatment.

cancer biology↗