COMPOSITION AND POSTTRANSLATIONAL MODIFICATION OF INDIVIDUAL COLLAGENCHAINS FROM OSTEOSARCOMAS AND OSTEOFIBROUS DYSPLASIAS

The composition of collagen was analyzed and the degree of lysyl hydro xylation of individual collagen chains was determined in four osteosar comas and two osteofibrous dysplasias. In addition, the tumor prolifer ation (number of mitoses, proliferating-nuclear-antigen-positive cells , MIB) as well as the response to chemotherapy (morphological regressi on grade) were checked. All tumors contained a high proportion of coll agen III and, in all but one osteosarcoma, pepsin-extracted collagens I and III were overmodified. Furthermore, the proportion of diglycosid es in collagen I was about four times higher than in controls. The col lagen composition and modification resembled those of bones at early s tages of human development. One osteosarcoma and both osteofibrous dys plasias were in the normal range of lysyl hydroxylation. There was no correlation between the collagen properties and the histopathological marker of tumor proliferation.