1,25-dihydroxyvitamin D3 synthetic analogs inhibit spontaneous metastases in a 1,2-dimethylhydrazine-induced colon carcinogenesis model.
In order to substantiate the role of vitamin D applicability for the prevention of colon cancer and its spontaneous metastases, the effect of 1,25-dihydroxyvitamin D3 and its synthetic analogs, 1, 25-dihydroxy-16,23Z-diene-26,27-hexafluoro-D3 (Ro 25-5317) and 1, 25-dihydroxy-16,23E-diene-26,27-hexafluoro-19-nor-D3 (Ro 25-9022), have been evaluated in a 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis model in Sprague-Dawley rats. In animals maintained on 2.75 nmol/kg 1,25-dihydroxyvitamin D3 diet no statistical difference was seen in tumor incidence when compared with control while in animals on 3.0 nmol/kg 1,25-dihydroxyvitamin D3 diet, the incidence of tumors was significantly lower. In animals maintained on 3.0 nmol/kg Ro 25-5317 diet also no statistical difference was seen in tumor incidence compared with control while in animals on 3. 5 nmol/kg Ro 25-5317 diet the incidence of tumors was significantly lower. The incidence of tumors in the group of animals maintained on 3.0 nmol/kg and 3.5 nmol/kg Ro 25-9022 was significantly lower, at 32.1% and 27.6% respectively, compared to control. In the two groups of animals maintained on the 1,25-dihydroxyvitamin D3 diet no significant difference in the incidence of metastasis was seen. In the group of animals maintained on 3.0 nmol/kg Ro 25-5317 diet only regional metastases were seen. However, no metastases developed in the rats on 3.5 nmol/kg Ro 25-5317 diet. After administration of 3.0 nmol/kg Ro 25-9022 diet, metastases developed in a significantly less number of animals while no metastases occurred in the rats maintained on the 3.5 nmol/kg Ro 25-9022 diet. The above studies will provide a scientific basis for the progression into further clinical trials in the treatment, and/or chemoprevention of human colorectal cancer.
Evans
S R
SR
Department of Surgery, George Washington University Medical Center, NW, Washington, DC 20037, USA.
Shchepotin
E I
EI
Young
H
H
Rochon
J
J
Uskokovic
M
M
Shchepotin
I B
IB
D019813:1,2-Dimethylhydrazine; D000818:Animals; D002117:Calcitriol / Q000031:analogs & derivatives / Q000627:therapeutic use*; D002118:Calcium / Q000097:blood; D002120:Calcium Channel Agonists / Q000627:therapeutic use*; D002273:Carcinogens; D015179:Colorectal Neoplasms / Q000139:chemically induced / Q000188:drug therapy* / Q000517:prevention & control; D006801:Humans; D051381:Rats; D017207:Rats, Sprague-Dawley
D002120:Calcium Channel Agonists; D002273:Carcinogens; D002117:Calcitriol; D019813:1,2-Dimethylhydrazine; D002118:Calcium