title: Compositional and structural alterations of proteoglycans in human rectum carcinoma with special reference to versican and decorin.
abstract: This study indicated that human normal rectum (HNR) and human rectum carcinoma (HRC) contained three populations of proteoglycans (PGs). About 63% of the HNR PGs, in terms of uronic acid, were heparan sulfate proteoglycans (HSPGs) of M(r) 500,000 with HS side-chains of M(r) 35,000. The other two populations were versican (29%) and decorin (8%) of M(r) 715,000 and 90,000, respectively, bearing mainly dermatan sulfate (DS) (73%) and chondroitin sulfate (CS) (27%) chains of M(r) 24-26,000 and 20-22,000, respectively. In contrast, in terms of uronic acid, HRC contained 2-fold amounts of PGs. The majority of these PGs (87%) were versican and decorin of lower hydrodynamic size (500,000 and 70,000, respectively) than in HNR, with CS as prominent GAG (70%) in both types of PG. The M(r) of CS and DS chains in these PGs was 12-14,000 and 14-16,000, respectively. The remaining portion (13%) of PG was HSPGs of lower hydrodynamic size (300,000) with smaller HS chains (29,000) than HSPGs of HNR. Moreover, the molar concentrations of versican and decorin estimated from PG-derived protein contents represented a significant, but disproportionate increase, about 5-fold and 8-fold, respectively. The sulfation pattern of rectum carcinoma-associated versican and decorin was significantly altered mainly in containing (62%) 6-sulfated disaccharides and a significant proportion (10%) of non-sulfated disaccharides. DS chains of the tumor-associated versican and decorin contained decreased amounts of iduronic acid. On the metabolic level, the abnormally high production of versican and decorin in this malignant tumor suggests a dramatic modification in their biosynthetic steps at both translational and posttranslational levels.
authors.affiliation: Laboratory of Biological Chemistry, School of Medicine, University of Patras, 261 10 Greece.
authors.forename: Marina E
authors.initials: ME
authors.lastname: Tsara
authors.forename: Achilleas D
authors.initials: AD
authors.lastname: Theocharis
authors.forename: Dimitrios A
authors.initials: DA
authors.lastname: Theocharis
mesh_terms: D000368:Aged; D011508:Chondroitin Sulfate Proteoglycans / Q000032:analysis / Q000378:metabolism*; D002845:Chromatography / Q000379:methods; D058575:Decorin; D016326:Extracellular Matrix Proteins; D005260:Female; D006595:Hexosamines / Q000032:analysis / Q000378:metabolism; D006801:Humans; D037181:Lectins, C-Type; D008297:Male; D008875:Middle Aged; D011509:Proteoglycans / Q000032:analysis / Q000378:metabolism*; D012004:Rectal Neoplasms / Q000737:chemistry / Q000378:metabolism*; D014574:Uronic Acids / Q000032:analysis / Q000378:metabolism; D053675:Versicans
chemical_list: D011508:Chondroitin Sulfate Proteoglycans; C546878:DCN protein, human; D058575:Decorin; D016326:Extracellular Matrix Proteins; D006595:Hexosamines; D037181:Lectins, C-Type; D011509:Proteoglycans; D014574:Uronic Acids; C508322:VCAN protein, human; D053675:Versicans