Novel oligosaccharide has suppressive activity against human leukemia cell proliferation

Abstract

Various oligosaccharides containing galactose(s) and one glucosamine (or N-acetylglucosamine) residues with β1-4, α1-6 and β1-6 glycosidic bond were synthesized; Galβ1-4GlcNH 2 , Galα1-6GlcNH 2 , Galα1-6GlcNAc, Galβ1-6GlcNH 2 , Galβ1-4Galβ1-4GlcNH 2 and Galβ1-4Galβ1-4GlcNAc. Galα1-6GlcNH 2 (MelNH 2 ) and glucosamine (GlcNH 2 ) had a suppressive effect on the proliferation of K562 cells, but none of the other saccharides tested containing GlcNAc showed this effect. On the other hand, the proliferation of the human normal umbilical cord fibroblast was suppressed by none of the saccharides other than GlcNH 2 . Adding Galα1-6GlcNH 2 or glucosamine to the culture of K562 cell, the cell number decreased strikingly after 72 h. Staining the remaining cells with Cellstain Hoechst 33258, chromatin aggregation was found in many cells, indicating the occurrence of cell death. Furthermore, all of the cells were stained with Galα1-6GlcNH-FITC (MelNH-FITC). Neither the control cells nor the cells incubated with glucosamine were stained. On the other hand, when GlcNH-FITC was also added to cell cultures, some of them incubated with Galα1-6GlcNH 2 were stained. The difference in the stainability of the K562 cells by Galα1-6GlcNH-FITC and GlcNH-FITC suggests that the intake of Galα1-6GlcNH 2 and the cell death induced by this saccharide is not same as those of glucosamine. The isolation of the Galα1-6GlcNH 2 binding protein was performed by affinity chromatography (melibiose-agarose) and LC-MS/MS, and we identified the human heterogeneous ribonucleoprotein (hnRNP) A1 (34.3 kDa) isoform protein (30.8 kDa). The hnRNP A1 protein was also detected from the eluate(s) of the MelNH-agarose column by the immunological method (antihnRNP-A1 and HRP-labeled anti-mouse IgG (γ) antibodies).

Melibiosamine, a novel oligosaccharide, suppresses mitogen-induced IL-2 production via inactivation of NFAT and NFκB in Jurkat cells

“…We previously reported that GlcNH 2 at 5 mM significantly ( P < 0.01) suppressed the growth of human K562 leukemia cells and human HUC-F2 (non-transformed) cells, whereas MelNH 2 at 5 mM significantly ( P < 0.01) suppressed the cell growth of K562 cells but not of HUC-F2 cells, as assessed at day 3 after exposure [ 26 ]. This suggests that GlcNH 2 is toxic to both tumor cells and non-transformed cells, whereas MelNH 2 is toxic to tumor cells but not to non-transformed cells.…”

“…Jurkat cells were maintained at 37 °C (5% CO 2 ) in tissue-culture dishes containing RPMI 1640 growth medium supplemented with 10% (v/v) fetal bovine serum, 25 μg/mL penicillin, and 50 μg/mL streptomycin. MelNH 2 was synthesized as described previously [ 26 ], and GlcNH 2 was purchased from Sigma (St. Louis, MO); these compounds were each dissolved in phosphate-buffered saline (pH 7.4) as 0.1 M solutions, sterilized through a 0.45-μm filter, and stored at −20 °C until use. Phorbol 12-myristate 13-acetate (PMA) and ionomycin (IM) were obtained from Sigma, and CsA was purchased from Calbiochem (San Diego, CA), and these compounds were stored as 1, 0.5, and 0.5 mM stock solutions, respectively, in dimethyl sulfoxide (DMSO).…”

“…Recently, a novel GlcNH 2 -containing oligosaccharide, Galα1-6GlcNH 2 (designated melibiosamine; MelNH 2 ) (Fig. 1A), was found to exhibit anti-proliferative effects in human leukemia and breast cancer cells in vitro [26,27]. However, the potential biological and pharmacological activities of MelNH 2 are yet to be fully elucidated.…”

Functional oligosaccharides: production, properties and applications

“…6) and b-(1 ? 6) glycosidic bonds suppressed the proliferation of human leukemia K562 cells (Hosomi et al 2009). Iwata et al (2005) investigated the effects of chitosan oligosaccharides on the femur trabecular structure in ovariectomized rats by three-dimensional imaging analysis using micro-computed tomography (CT).…”