Relationship between fecal neutral steroid concentrations and malignancy in colon cells

Analysis of total and individual fecal neutral steroids in different groups of intestinal pathology from 105 patients was performed to investigate a relationship between neutral steroid concentration and malignant potentiality of colon cells. The fecal concentration of total neutral steroids was significantly higher in patients with colon cancer (57.3 +/- 2.4 mmol/kg of wet feces) and patients with malignant degenerative polyps at Stage I or II (49.5 +/- 2.9) compared with controls (36.9 +/- 3.5) as well as patients with adenomatous polyps (22.4 +/- 2.0). Moreover, a significant correlation was found between total neutral steroid concentrations and coprostanol concentrations in patients with colon cancer (r = 0.928) and in patients with malignant polyps (r = 0.915). Coprostanol results only from the biohydrogenation of delta 5-3 beta-OH steroids by anerobic bacteria because the analysis of a malignant colon tumor in comparison with a healthy colon wall showed that cholesterol is the only steroid included in membrane cells, and that the incubation of Clostridium or Bacteroides with delta 5-3 beta-OH steroids, such as cholesterol (steroid of animal origin) or beta-sitosterol (steroid of plant origin) converts these steroids into coprostanol at a level of efficiency greater than 45%. The findings suggest that high levels of coprostanol reflecting a high growth of anerobic bacteria through the gut are related to the malignant potentiality of colon cells. The screening of neutral fecal steroids should provide a valuable parameter for predicting the malignancy of colon cells.