cholecalciferol and Adenomatous-Polyposis-Coli

Colorectal cancer (CRC) is the second most common malignancy in the world and a leading cause of cancer death. Prevention can lead to decreased incidence of this neoplasm. Chemoprevention may be one option. The article presents a summary of the main information on CRC chemoprevention based on internet database MEDLINE.

Topics: Adenomatous Polyposis Coli; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Combined Chemotherapy Protocols; Calcium; Chemoprevention; Cholecalciferol; Colonoscopy; Colorectal Neoplasms; Colorectal Neoplasms, Hereditary Nonpolyposis; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Early Diagnosis; Folic Acid; Humans; Mass Screening; Randomized Controlled Trials as Topic; Rectal Neoplasms; SEER Program

Both epidemiological and experimental findings have indicated that components of Western diets influence colonic tumorigenesis. Among dietary constituents, calcium and cholecalciferol have emerged as promising chemopreventive agents. We have demonstrated that a Western-style diet (WD) with low levels of calcium and cholecalciferol and high levels of (n-6) PUFA, increased the incidence of neoplasia in mouse intestine compared with a standard AIN-76A diet; models included wild-type mice and mice with targeted mutations. In the present study, adenomatous polyposis coli (Apc)(1638N/+) mice carrying a heterozygous Apc mutation were fed either an AIN-76A diet, a WD, or a WD supplemented with calcium and cholecalciferol (WD/Ca/VitD3). Diets were fed for 24 wk and effects on cellular and molecular events were assessed by performing immunohistochemistry in colonic epithelium along the crypt-to-surface continuum. Feeding WD to Apc(1638N/+) mice not only enhanced cyclin D1 expression in colonic epithelium compared with AIN-76A treatment as previously reported but also significantly increased the expression of the antiapoptotic protein B-cell lymphoma 2 (Bcl-2) concomitantly with a decrease in the proapoptotic Bcl2-associated X protein and the number of apoptotic epithelial cells. WD treatment enhanced mutant Apc-driven small intestinal carcinogenesis and also resulted in the formation of a small number of colonic adenomas (0.16 +/- 0.09; P < 0.05). By contrast, the WD/Ca/VitD3 diet reversed WD-induced growth, promoting changes in colonic epithelium. Importantly, Apc(1638N/+) mice fed the WD/Ca/VitD3 diet did not develop colonic tumors, further indicating that dietary calcium and cholecalciferol have a key role in the chemoprevention of colorectal neoplasia in this mouse model of human colon cancer.

Topics: Adenomatous Polyposis Coli; Adenomatous Polyposis Coli Protein; Animals; Apoptosis; bcl-2-Associated X Protein; Body Weight; Calcium, Dietary; Carcinogenicity Tests; Cholecalciferol; Colon; Cyclin D1; Diet; Disease Models, Animal; Female; Gene Expression Regulation, Neoplastic; Male; Mice; Mutation; Proto-Oncogene Proteins c-bcl-2; Random Allocation

Both calcium and vitamin D are thought to be able to inhibit colon carcinogenesis. To better define the effects of vitamin D, we studied 1alpha,25-(OH)(2)-D(3) and a noncalcemic synthetic analogue of vitamin D(3) (VD(3)) in the Apc(min) mouse. Female Apc(min) mice 4-5 weeks old were randomized to four groups: a VD(3)-treated group (n = 11) were given injections of 0.01 microg of 1alpha,25-(OH)(2)-D(3) i.p. three times per week; an analogue-treated group (n = 10) received 5 microg of 1alpha,25-(OH)(2)-16-ene-19-nor-24-oxo-D(3) i.p. three times per week; and a control group (n = 12) received sham injections of PBS. A sulindac-treated group (n = 10) was used as a positive control. Doses of these compounds were chosen based on previous toxicity studies in mice and rats. After 10 weeks of treatment, mice were killed and two observers (S. H., R. W. I.), blinded to treatment, scored polyp number and size. Tumor number was not affected with 1alpha,25-(OH)(2)-D(3) or vitamin D analogue administration. A significant decrease in total tumor load (sum of all polyp areas) over the entire gastrointestinal tract was seen in the analogue (36% decrease; P < 0.05) and the VD(3) groups (46%; P < 0.001). There was a significant decrease in polyp number (49%; P < 0.001) and polyp area (70%; P < 0.001) in the sulindac group. Reverse transcription-PCR of the total RNA derived from intestinal tissue revealed expression of the vitamin D receptor throughout the small intestine and the colon. Serum calcium levels in the analogue group were not elevated at week 4 of treatment and only moderately elevated (22%) by week 8 (P < or =0.001). In contrast, serum calcium in the VD(3) group was significantly elevated (P < or =0.001) at weeks 4 (23%) and 8 (45%). Food intake and growth rate were significantly lower in the VD(3) group (26%, P < 0.001, and 27%, P < 0.001, respectively) at week 10. In contrast, food intake and growth rate were similar for the control, sulindac, and analogue groups. Our results indicate that a noncalcemic analogue of vitamin D can significantly decrease intestinal tumor load in Apc(min) mice without severe toxic side effects and suggest that these compounds may have utility as chemopreventive agents in groups at high-risk for colon cancer.

Topics: Adenomatous Polyposis Coli; Animals; Body Weight; Calcitriol; Calcium; Cholecalciferol; Colonic Neoplasms; Eating; Female; Mice; Mice, Inbred C57BL; Receptors, Calcitriol