title: Collagen polymorphism in extracellular matrix of human osteosarcoma.
abstract: The collagenous matrix of human osteosarcoma was characterized biochemically and ultrastructurally. The highly cellular regions of the tumors contained many osteoblast-like cells filled with dilated rough endoplasmic reticulum. The extracellular matrix displayed a random weave of banded collagen fibrils (30--90 nm in diameter) interspersed with thinner, unbanded fibrils (15 nm in diameter). Tumors from 9 patients were analyzed for collagen composition. All gave a similar collagen profile. Three main molecular species of collagen were abundant: type I, type III, and type V, which occurred in the approximate proportions of 65:25:10. A high ratio of alpha 1(I) to alpha 2(I) chains suggested that one-third of the type I collagen was present as a type I trimer molecule. In contrast, normal bone matrix consisted almost exclusively of type I collagen. The fibrillar collagens in the soft tumor seemed unusually rich in hydroxylysine and hydroxylysine glycosides; type I collagen had two to three times the hydroxylysine content of normal bone collagen.
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000378:metabolism* / Q000648:ultrastructure; D002648:Child; D003094:Collagen / Q000032:analysis / Q000235:genetics*; D005110:Extracellular Space / Q000032:analysis; D006801:Humans; D006901:Hydroxylysine / Q000031:analogs & derivatives / Q000032:analysis; D008970:Molecular Weight; D012516:Osteosarcoma / Q000378:metabolism* / Q000648:ultrastructure; D011110:Polymorphism, Genetic
chemical_list: C022819:hydroxylysine glycoside; D006901:Hydroxylysine; D003094:Collagen