Type I and III collagens in human colon cancer and diverticulosis.
BACKGROUND
Collagens are major proteins in the extracellular matrix, providing tissues with tensile strength. They are also important for cell adhesion and the invasion of malignant tumours.


METHODS
Thirty-nine samples of human colon (24 diverticulosis, 6 malignant tumours, 9 controls) were collected during elective surgery. Immunoassays for different domains of type I and III collagens and procollagens were used in soluble tissue extracts and trypsin digests of tissue samples.


RESULTS
The contents of cross-linked type I and III collagen telopeptides and total collagen were similar in diverticulosis and healthy tissue, whereas in malignant tissue maturely cross-linked type III collagen was scarce. Furthermore, some of the cross-linked type I telopeptide antigens were exceptionally small in size, indicating that the cross-linking of type I collagen in collagen fibres is impaired in cancer. The rate of type I collagen synthesis was clearly increased in malignancy, but not significantly in diverticulosis. However, type III collagen synthesis was increased in diverticulosis, but not in malignancy.


CONCLUSIONS
In colon malignancy, the collagen cross-linking process was aberrant and the synthesis of type I collagen increased. In diverticulosis, the synthesis of type III collagen was increased, suggesting only moderately increased metabolic activity.
Bode
M K
MK
Dept. of Clinical Chemistry, University of Oulu, Finland.
Karttunen
T J
TJ
Mäkelä
J
J
Risteli
L
L
Risteli
J
J
D000328:Adult; D000368:Aged; D003094:Collagen / Q000032:analysis* / Q000096:biosynthesis; D003106:Colon / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000378:metabolism*; D004241:Diverticulum, Colon / Q000378:metabolism*; D005260:Female; D006801:Humans; D006909:Hydroxyproline / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000032:analysis; D011347:Procollagen / Q000032:analysis
D010446:Peptide Fragments; D011347:Procollagen; C047202:procollagen Type I N-terminal peptide; C041876:procollagen Type III-N-terminal peptide; D003094:Collagen; D006909:Hydroxyproline