Structure determination, apoptosis induction, and telomerase inhibition of CFP-2, a novel lichenin from Cladonia furcata.
A great deal of experimental evidence has accumulated in the past several decades, suggesting that polysaccharides have wide bioactivities. Cladonia furcata polysaccharide, CFP-2, a water-soluble lichenin with a mean Mr 7.6 x 10(4), was first obtained by 0.25 M NaOH solution extraction, ethanol precipitation, DEAE-cellulose, and Sephadex G-200 column chromatography. Gas chromatography of acid hydrolyzate of CFP-2 suggested that it was composed of D-glucose, D-galactose, and D-mannose in the molar ratios of 8:1:1. Periodate oxidation, Smith degradation, IR, and NMR spectroscopy analysis revealed that CFP-2 had a backbone consisting of alpha-(1-->3) and alpha-(1-->4)-linked D-glucopyranosyl residues substituted at O-6 with beta-(1-->6)-linked D-galactopyranosyl residue and alpha-(1-->6)-linked D-mannopyranosyl residue. CFP-2 was able to reduce viability of cultured HL-60 and K562 cells. The antiproliferative properties of CFP-2 appeared to be attributable to its induction of apoptotic cell death as determined by ultrastructural change, internucleosomal DNA fragmentation, and increased proportion of the subdiploid cell population. To elucidate molecular events in the apoptosis, protein expressions of Bcl-2, Bax, Fas, and FasL were measured by Western blotting using specific antibodies in HL-60 cells. The level of Bcl-2 remained largely unchanged, but the Bax, Fas, and FasL expression showed up-regulation. Moreover, the telomerase activity analyzed by TRAP-ELISA assay in HL-60 cells treated with CFP-2 decreased as compared with the untreated control cells. These results suggest that CFP-2 could have a possible cancer therapeutic potential.
Lin
Xin
X
Department of Biochemistry and Molecular Biology, School of Life Science, Lanzhou University, Tianshui Road 298 #, Lanzhou, Gansu 730000, China.
Cai
Yu-Jun
YJ
Li
Zhi-Xiao
ZX
Chen
Qian
Q
Liu
Zhong-Li
ZL
Wang
Rui
R
D017209:Apoptosis; D001203:Ascomycota / Q000737:chemistry*; D002240:Carbohydrate Sequence; D045744:Cell Line, Tumor / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D053938:DNA Fragmentation; D053222:Fas Ligand Protein; D005936:Glucans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D018922:HL-60 Cells / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008562:Membrane Glycoproteins / Q000032:analysis; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011134:Polysaccharides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D019253:Proto-Oncogene Proteins c-bcl-2; D019098:Telomerase / Q000037:antagonists & inhibitors; D051028:bcl-2-Associated X Protein; D019014:fas Receptor / Q000032:analysis
C494826:BAX protein, human; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D005936:Glucans; D008562:Membrane Glycoproteins; D011134:Polysaccharides; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D019014:fas Receptor; D019098:Telomerase; C015968:lichenin