RESUMO
High-grade serous ovarian cancer (HGSOC) is the most lethal gynecological malignancy in women worldwide and the fifth most common cause of cancer-related deaths among U.S. women. New therapies are needed to treat HGSOC, particularly because most patients develop resistance to current first-line therapies. Many natural product and fungal metabolites exhibit anticancer activity and represent an untapped reservoir of potential new agents with unique mechanism(s) of action. Verticillin A, an epipolythiodioxopiperazine alkaloid, is one such compound, and our recent advances in fermentation and isolation are now enabling evaluation of its anticancer activity. Verticillin A demonstrated cytotoxicity in HGSOC cell lines in a dose-dependent manner with a low nmol/L IC50 Furthermore, treatment with verticillin A induced DNA damage and caused apoptosis in HGSOC cell lines OVCAR4 and OVCAR8. RNA-Seq analysis of verticillin A-treated OVCAR8 cells revealed an enrichment of transcripts in the apoptosis signaling and the oxidative stress response pathways. Mass spectrometry histone profiling confirmed reports that verticillin A caused epigenetic modifications with global changes in histone methylation and acetylation marks. To facilitate in vivo delivery of verticillin A and to monitor its ability to reduce HGSOC tumor burden, verticillin A was encapsulated into an expansile nanoparticle (verticillin A-eNP) delivery system. In an in vivo human ovarian cancer xenograft model, verticillin A-eNPs decreased tumor growth and exhibited reduced liver toxicity compared with verticillin A administered alone. This study confirmed that verticillin A has therapeutic potential for treatment of HGSOC and that encapsulation into expansile nanoparticles reduced liver toxicity.
Assuntos
Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Dano ao DNA/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Animais , Apoptose , Linhagem Celular Tumoral , Cistadenocarcinoma Seroso/patologia , Feminino , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Camundongos , Camundongos Nus , Neoplasias Ovarianas/patologia , Carga TumoralRESUMO
Six fungal metabolites, of which five were new, including one (1) with a dioxa[4.3.3]propellane ring system, were discovered, identified, and structurally elucidated from Neosetophoma sp. (strain MSX50044); these compounds are similar to the bis-tropolone, eupenifeldin. Three of the meroterpenoids are potent cytotoxic agents against breast, ovarian, mesothelioma, and lung cancer cells with nanomolar IC50 values while not inducing mitochondrial toxicity at 12.5 µM.