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Ferretti, S.

Publications and source records attributed to Ferretti, S..

2 recordsLinked to original sources

Suppression of YAP/TAZ molecular targets by epigenetic editing interferes with GBM growth and invasiveness

Glioblastoma (GBM) is a highly aggressive brain tumor characterized by extensive heterogeneity, diffuse invasion, and recurrence despite multimodal therapy. Aberrant transcriptional programs driven by oncogenic signaling pathways sustain GBM growth, stemness, and therapy resistance, yet targeting individual molecular nodes has yielded limited clinical benefit. Here, we introduce a transcriptional rewiring strategy based on an engineered epigenetic silencer factor (ESF) targeting the YAP/TAZ-TEAD axis. We developed a TEAD1 Epigenetic Silencer (TES) by fusing the DNA-binding domain of TEAD1 to repressive epigenetic modules. TES selectively binds TEAD genomic targets and imposes stable transcriptional repression of YAP/TAZ-dependent gene programs through chromatin remodeling and DNA methylation. Genome-wide analyses revealed that TES preserves TEAD1 DNA-binding specificity while converting an oncogenic transcriptional platform into a repressive state. Functionally, TES impaired proliferation, induced cell death, and reduced migratory and invasive properties in glioma cell lines and patient-derived cancer stem-like cells. In vivo, TES significantly reduced tumor growth in orthotopic GBM xenograft models and enhanced the therapeutic efficacy of temozolomide. Importantly, TES was well tolerated by normal neural cells in vitro and in the adult mouse brain in vivo. These findings establish TES as a proof-of-concept epigenetic therapy to durably suppress oncogenic transcriptional networks in GBM.

cancer biology↗

Therapeutic assessment of targeting ASNS combined with L-Asparaginase treatment in solid tumors and investigation of resistance mechanisms

Asparagine deprivation by L-Asparaginase (L-ASNase) is an effective therapeutic strategy in Acute Lymphoblastic Leukemia, with resistance occurring due to upregulation of ASNS, the only human enzyme synthetizing Asparagine1. L-Asparaginase efficacy in solid tumors is limited by dose-related toxicities 2. Large-scale loss of function genetic in vitro screens identified ASNS as a cancer dependency in several solid malignancies 3,4. Here we evaluate the therapeutic potential of targeting ASNS in melanoma cells. While we confirm in-vitro dependency on ASNS silencing, this is largely dispensable for in vivo tumor growth, even in face of asparagine deprivation, prompting us characterize such resistance mechanism to devise novel therapeutic strategies. Using ex vivo quantitative proteome and transcriptome profiling, we characterize the compensatory mechanism elicited by ASNS knockout melanoma cells allowing their survival. Mechanistically, a genome-wide CRISPR screen revealed that such resistance mechanism is elicited by a dual axis: GCN2-ATF4 aimed at restoring amino acids levels and MAPK-BCLXL to promote survival. Importantly, pharmacological inhibition of such nodes synergizes with L-Asparaginase-mediated Asparagine deprivation in ASNS deficient cells suggesting novel potential therapeutic combinations in melanoma.

cancer biology↗