Collagen metabolism in human colon adenocarcinoma

The collagen metabolism has been studied in a human colonic adenocarcinoma. The overall collagen content was decreased in the tumor. The internal layers of the tumor tissue have the lower collagen content. Stroma cells and epithelial transformed cells, obtained from colon adenocarcinoma explants, were "in vitro" cultured in order to explain the decreased collagen content in the tumor. Cells from the epithelial lineage (both round-shape cells, and those derived from them, epithelial-like cells) showed an almost negligible ability for collagen synthesis. Stroma cells (fibroblast-like cells) maintained a normal ability for collagen biosynthesis but exhibited a 2-fold increased non-collagenous protein synthesis as well as a decreased collagen secretion, when compared with control fibroblasts from non-affected colon regions. The alterations in the stroma cells are not due to soluble factors produced by adenocarcinoma cells. Thus, the fibroblast-like cells, which have been studied for the first time, would be related to the alterations of the extracellular matrix contributing to the invasiveness of the tumor cells.