Abstract
Ovarian cancer (OC) is one of the deadliest cancers, with high relapse and resistance rates despite current treatments. The enzyme nicotinamide phosphoribosyltransferase (NAMPT), particularly in its extracellular form (eNAMPT), plays a key role in tumor processes including DNA repair, proliferation, metastasis, and drug resistance. However, its role in OC remains poorly understood. This project aims to investigate the pathological role of eNAMPT in OC, hypothesizing that it promotes aggressive tumor phenotypes via EMT and stemness modulation. Preliminary data show elevated eNAMPT levels in OC ascitic fluid, indicating its potential as a biomarker. The study is structured in four work packages: WP1 evaluates eNAMPT levels in patient samples and correlates them with clinical outcomes; WP2 and WP3 explore its function using in vitro and in vivo models; WP4 tests the efficacy of an anti-eNAMPT monoclonal antibody (C269). The ultimate goal is to assess eNAMPT as a therapeutic target in OC. Results Clinical analyses demonstrated that extracellular NAMPT is highly enriched in ovarian cancer ascites compared with serum, supporting its predominant role within the tumor microenvironment. Elevated ascitic eNAMPT levels were significantly associated with tumor grade, histological subtype, and progression-free survival, indicating that eNAMPT reflects biologically relevant features of disease progression and may serve as a clinically informative biomarker. In parallel, intracellular NAMPT expression was significantly increased in ovarian tumor tissues compared with matched normal samples, confirming dysregulation of the NAMPT axis during ovarian carcinogenesis. Mechanistic studies revealed that increasing extracellular NAMPT levels did not directly enhance ovarian cancer cell proliferation, suggesting that its tumor-promoting activity is primarily mediated through remodeling of the tumor microenvironment rather than through direct stimulation of malignant cells. To investigate these mechanisms in physiologically relevant settings, we successfully established robust ovarian cancer spheroid cultures and optimized 3D bioprinted models, creating versatile experimental platforms for studying tumor–stroma interactions and evaluating therapeutic responses under conditions that closely mimic the native tumor microenvironment. Pharmacological studies demonstrated that neutralization of extracellular NAMPT using the monoclonal antibody C269 exerted only modest effects on tumor cell viability, indicating that selective blockade of the secreted cytokine is insufficient to impair ovarian cancer growth. In contrast, next-generation PROTAC molecules capable of simultaneously degrading intracellular and extracellular NAMPT efficiently reduced NAMPT expression and induced marked cytotoxicity in the murine ID8 ovarian cancer model. These findings identify targeted degradation of the NAMPT pathway as a substantially more effective therapeutic strategy than extracellular neutralization alone and provide the first evidence supporting dual NAMPT targeting as a promising approach for ovarian cancer treatment. Collectively, this project establishes the NAMPT pathway as a previously underappreciated regulator of ovarian cancer biology, provides clinically relevant evidence supporting the biomarker potential of extracellular NAMPT, and delivers innovative preclinical models together with proof-of-concept therapeutic data. These findings lay the foundation for future translational studies aimed at developing NAMPT-directed therapies and advancing more effective precision medicine strategies for ovarian cancer.
Dettagli del progetto
Responsabile scientifico: Gloria Ravegnini
Strutture Unibo coinvolte:
Dipartimento di Farmacia e Biotecnologie
Coordinatore:
ALMA MATER STUDIORUM - Università di Bologna(Italy)
Contributo totale di progetto: Euro (EUR) 224.000,00
Contributo totale Unibo: Euro (EUR) 112.000,00
Durata del progetto in mesi: 24
Data di inizio
16/10/2023
Data di fine:
28/02/2026
