Protoflavonoids from Ferns Impair Centrosomal Integrity of Tumor Cells

Abstract

Six protoflavonoids, including two new compounds, were isolated during a large scale screening of fern extracts for original interaction with mitosis. The new compounds isolated from Phegopteris decursive-pinnata and Equisetum fluviatile were 2′,3′-dihydroprotogenkwanone (1) and 2′,3′-dihydro-2′-hydroxyprotoapigenone (2). Known compounds were: protoapigenone, protogenkwanone, protoapigenin, and 4′-O-β-D-glucopyranosyl protoapigenin. They showed a cytotoxic activity against HeLa cells at a micromolar level. IC₅₀ values were 2 µM for compound 1, > 10 µM for compound 2, and respectively 2.4, 0.6, > 10 µM for the known compounds. Their cytotoxic effects were associated with phenotypic changes never observed before and characterized by the loss of centrosomal γ-tubulin labelling in both mitotic and interphasic cells.

Key words

protoflavonoids - ferns - Phegopteris decursive‐pinnata - Thelypteridaceae - Equisetum fluviatile - Equisetaceae - γ‐tubulin - centrosome

References

• 1 Sudakin V, Yen T J. Targeting mitosis for anti-cancer therapy.  Bio Drugs. 2007;  21 225-233
• 2 Imperato F. Bioactive natural products from Pteridophyta.  Recent Res Dev Phytochem. 2001;  5 191-228
• 3 Imperato F. Advances in phytochemistry of Pteridophyta since 1999.  Curr Top Phytochem. 2007;  8 1-21
• 4 Joshi H C, Palacios M J, McNamara L, Cleveland D W. γ-Tubulin is a centrosomal protein required for cell cycle-dependent microtubule nucleation.  Nature. 1992;  356 80-83
• 5 Yuba-Kubo A, Kubo A, Hata M, Tsukita S. Gene knockout analysis of two γ-tubulin isoforms in mice.  Dev Biol. 2005;  282 361-373
• 6 Haren L, Remy M H, Bazin I, Callebaut I, Wright M, Merdes A. NEDD1-dependent recruitment of the γ-tubulin ring complex to the centrosome is necessary for centriole duplication and spindle assembly.  J Cell Biol. 2006;  172 505-515
• 7 Lajoie-Mazenc I, Tollon Y, Detraves C, Julian M, Moisand A, Gueth-Hallonet C, Debec A, Salles-Passador I, Puget A, Mazarguil H, Raynaud-Messina B, Wright M. Recruitment of antigenic gamma-tubulin during mitosis in animal cells: presence of gamma-tubulin in the mitotic spindle.  J Cell Sci. 1994;  107 2825-2837
• 8 Krzaczkowski L, Wright M, Rebérioux D, Massiot G, Etiévant C, Gairin J E. Pharmacological screening of bryophyte extracts that inhibit growth and induce abnormal phenotypes in human HeLa cancer cells.  Fundam Clin Pharmacol. 2009;  23 473-482
• 9 Quadri-Spinelli T, Heilmann J, Rali T, Sticher O. Bioactive coumarin derivatives from the fern Cyclosorus interruptus.  Planta Med. 2000;  66 728-733
• 10 Lin A S, Chang F R, Wu C C, Liaw C C, Wu Y C. New cytotoxic flavonoids from Thelypteris torresiana.  Planta Med. 2005;  71 867-870
• 11 Lin A S, Nagakawa-Goto K, Chang F R, Yu D, Morris-Natschke S L, Wu C C, Chen S L, Wu Y C, Lee K H. First total synthesis of protoapigenone and its analogues as potent cytotoxic agents.  J Med Chem. 2007;  50 3921-3927
• 12 Chang H L, Su J H, Yeh Y T, Lee Y C, Chen H M, Wu Y C, Yuan S S F. Protoapigenone, a novel flavonoid, inhibits ovarian cancer cell growth in vitro and in vivo.  Cancer Lett. 2008;  267 85-95
• 13 Lin A S, Wu Y C, Lee K S, Chang F R. Composition for treating cancer cells and synthetic methods for the same. European Patent EP20080006865; 2008. 
• 14 Chiu C C, Chang H W, Chuang D W, Chang F R, Chang Y C, Cheng W Y, Tsai M T, Chen W Y, Lee S S, Wang C K, Chen J Y, Wang H M, Chen C C, Liu Y C, Wu Y C. Fern plant-derived protoapigenone leads to DNA damage, apoptosis, and G2/M arrest in lung cancer cell line H1299.  DNA Cell Biol. 2009;  28 501-506
• 15 Veit M, Beckert C, Höhne C, Bauer K, Geiger H. Interspecific and intraspecific variation of phenolics in the genus Equisetum subgenus Equisetum.  Phytochemistry. 1995;  38 881-891
• 16 Wada H, Fujita H, Murakami T, Saiki Y, Chen C M. Chemical and chemotaxonomical studies of ferns. LXXIII. New flavonoids with modified B-ring from the genus pseudophegopteris (thelypteridaceae).  Chem Pharm Bull. 1987;  35 4757-4762
• 17 Stomberg R, Lundquist K, Hauteville M, Geiger H. Crystal structure of protogenkwanine.  J Crystallogr Spectrosc Res. 1991;  21 183-188
• 18 Adam K-P. Phenolic constituents of the fern Phegopteris connectilis.  Phytochemistry. 1999;  52 929-934
• 19 Noro T, Fukushima S, Saiki Y, Ueno A, Akaori Y. Studies on the constituents of Leptorumohra miqueliana H. ITO. II. The structure of protofarrerol.  Yakugaku Zasshi. 1969;  89 851-856
• 20 Hauteville M, Chopin J, Geiger H, Schüler L. Protogenkwanin 4′-glucoside, a new type of natural flavonoid with a non aromatic B-ring.  Tetrahedron Lett. 1980;  21 1227-1230
• 21 Dewick P M. Medicinal natural products, a biosynthetic approach, 2nd edition. New York; John Wiley & Sons 2002: 149-151