N-Acetyllactosamine (LacNAc; Galβ4GlcNAc) is a typical disaccharide ligand of galectins. The most abundant members of these human lectins, galectin-1 (Gal-1) and galectin-3 (Gal-3), participate in a number of pathologies including cancerogenesis and metastatic formation. In this study, we synthesized a series of fifteen N-(2-hydroxypropyl)methacrylamide (HPMA)-based glycopolymers with varying LacNAc amounts and presentations and evaluated the impact of their architecture on the binding affinity to Gal-1 and Gal-3. The controlled radical reversible addition-fragmentation chain transfer copolymerization technique afforded linear polymer precursors with comparable molecular weight (Mn ≈ 22,000 g mol-1) and narrow dispersity (D̵ ≈ 1.1). The precursors were conjugated with the functionalized LacNAc disaccharide (4-22 mol % content in glycopolymer) prepared by enzymatic synthesis under catalysis by β-galactosidase from Bacillus circulans. The structure-affinity relationship study based on the enzyme-linked immunosorbent assay revealed that the type of LacNAc presentation, individual or clustered on bi- or trivalent linkers, brings a clear discrimination (almost 300-fold) between Gal-1 and Gal-3, reaching avidity to Gal-1 in the nanomolar range. Whereas Gal-1 strongly preferred a dense presentation of individually distributed LacNAc epitopes, Gal-3 preferred a clustered LacNAc presentation. Such a strong galectin preference based just on the structure of a multivalent glycopolymer type is exceptional. The prepared nontoxic, nonimmunogenic, and biocompatible glycopolymers are prospective for therapeutic applications requiring selectivity for one particular galectin.
- MeSH
- akrylamidy chemie MeSH
- aminocukry chemie MeSH
- Bacillus enzymologie MeSH
- beta-galaktosidasa metabolismus MeSH
- disacharidy chemická syntéza MeSH
- ELISA MeSH
- epitopy MeSH
- galektin 1 analýza metabolismus MeSH
- galektiny analýza metabolismus MeSH
- katalýza MeSH
- krevní proteiny analýza metabolismus MeSH
- magnetická rezonanční spektroskopie MeSH
- polymerizace MeSH
- polymery chemie metabolismus farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A series of lupane-type saponins bearing OSW-1 disaccharide unit as well as its regio- and stereoisomers were prepared and used for the structure-activity relationships (SAR) study. Unexpected preference for 1→4-linked regioisomers and an unusual inversion of the conformation of the sugar rings were noted. Cytotoxic activity of new lupane compounds was evaluated in vitro and revealed that some saponins exhibited an interesting bioactivity profile against human cancer cell lines. Influence of the protecting groups on the cytotoxicity was investigated. These results open the way to the synthesis of various lupane-type triterpene and saponin derivatives as potential anticancer compounds.
- MeSH
- antitumorózní látky chemická syntéza chemie farmakologie MeSH
- arabinosa chemie MeSH
- disacharidy chemická syntéza chemie farmakologie MeSH
- glykosylace MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- saponiny chemie MeSH
- stereoizomerie MeSH
- techniky syntetické chemie MeSH
- triterpeny chemie MeSH
- vodíková vazba MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An approach to stereoselective synthesis of alpha- or beta-3-C-glycosylated L- or D-1,2-glucals starting from the corresponding alpha- or beta-glycopyranosylethanals is described. The key step of the approach is the stereoselective cycloaddition of chiral vinyl ethers derived from both enantiomers of mandelic acid. The preparation of 1,5-anhydro-4,6-di-O-benzyl-2,3-dideoxy-3-C-[(2,3,4,6-tetra-O-benzyl-beta-D-glucopyranosyl)methyl]-L-arabino-hex-1-enitol, 1,5-anhydro-4,6-di-O-benzyl-2,3-dideoxy-3-C-[(2,3,4,6-tetra-O-benzyl-beta-D-glucopyranosyl)methyl]-D-arabino-hex-1-enitol, and 1,5-anhydro-4,6-di-O-benzyl-2,3-dideoxy-3-C-[(2,3,4-tri-O-benzyl-alpha-L-fucopyranosyl)methyl]-D-arabino-hex-1-enitol serves as an example of this approach.