Effect of Added Dietary Calcium on Colonic Epithelial-Cell Proliferation in Subjects at High Risk for Familial Colonic Cancer

TLDR

We examined colonic crypt epithelial proliferation in 10 high‑risk subjects before and after 1.25 g/day calcium carbonate, defining patterns by dividing crypts into longitudinal compartments and comparing tritiated thymidine‑labeled cell counts. Calcium supplementation reduced proliferation over 2–3 months, shifting the crypt profile from that seen in familial cancer patients to one resembling low‑risk individuals, indicating a more quiescent equilibrium. Published in N Engl J Med 1985; 313:1381–4.

Abstract

We studied the frequency and distribution of proliferating epithelial cells lining colonic crypts in 10 subjects at high risk for familial colonic cancer, before and after oral supplementation of their conventional diets with 1.25 g of calcium as calcium carbonate. Patterns of cell proliferation were defined by dividing the colonic crypt into longitudinal compartments and comparing the numbers and fractions of tritiated thymidine—labeled epithelial cells in the various compartments. Before dietary supplementation with calcium, the profile of proliferating epithelial cells in the colonic crypts was comparable to that previously observed in subjects who had had familial colonic cancer. Two to three months after supplementation had been started, proliferation was significantly reduced and the profile of the colonic crypts approached that previously observed in subjects at low risk for colonic cancer. Our findings indicate that oral calcium supplementation induces a more quiescent equilibrium in epithelial-cell proliferation in the colonic mucosa of subjects at high risk of colon cancer, similar to that observed in subjects at low risk. (N Engl J Med 1985; 313:1381–4.)