Motuhi S. E. auteur aut IRD Feizbakhsh O. auteur aut IRD Foll-Josselin B. auteur aut IRD Baratte B. auteur aut IRD Delehouze C. auteur aut IRD Cousseau A. auteur aut IRD Fant X. auteur aut IRD Bulinski J. C. auteur aut IRD Payri Claude auteur aut IRD Ruchaud S. auteur aut IRD Mehiri M. auteur aut IRD Bach S. auteur aut IRD text journalArticle eng text/pdf reformatted digital access The marine -pyrone macrolide neurymenolide A was previously isolated from the Fijian red macroalga, Neurymenia fraxinifolia, and characterized as an antibacterial agent against antibiotic-resistant strains that also exhibited moderate cytotoxicity in vitro against cancer cell lines. This compound was also shown to exhibit allelopathic effects on Scleractinian corals. However, to date no mechanism of action has been described in the literature. The present study showed, for the first time, the isolation of neurymenolide A from the New Caledonian Rhodophyta, Phacelocarpus neurymenioides. We confirmed the compound's moderate cytotoxicity in vitro against several human cell lines, including solid and hematological malignancies. Furthermore, we combined fluorescence microscopy and flow cytometry to demonstrate that treatment of U-2 OS osteosarcoma human cells with neurymenolide A could block cell division in prometaphase by inhibiting the correct formation of the mitotic spindle, which induced a mitotic catastrophe that led to necrosis and apoptosis. Absolute configuration of the stereogenic center C-17 of neurymenolide A was deduced by comparison of the experimental and theoretical circular dichroism spectra. Since the total synthesis of this compound has already been described, our findings open new avenues in cancer treatment for this class of marine molecules, including a new source for the natural product. specialized New Caledonia Phacelocarpus neurymenioides Rhodophyta neurymenolide A mitotic spindle poison mitotic catastrophe necrosis apoptosis NOUVELLE CALEDONIE 035 020 17 2 art. 93 [18 ] 2019 1660-3397 https://www.documentation.ird.fr/hor/fdi:010075313 10.3390/md17020093 1660-3397 [F B010075313] https://www.documentation.ird.fr/hor/fdi:010075313 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers19-03/010075313.pdf IRD - Base Horizon / Pleins textes 2019-04-03 2025-02-24 fdi:010075313 fre