1,25-Dihydroxy-16-ene-23-yne-vitamin D3 and prostate cancer cell proliferation in vivo.
OBJECTIVE
1,25-Dihydroxyvitamin D can inhibit the proliferation of prostate cancer cells, but its clinical use is limited by hypercalcemia. We examined the effects of a "noncalcemic" vitamin D analogue, 1,25-Dihydroxy-16-ene-23-yne-cholecalciferol (16-23-D3), on the proliferation of human prostate cancer cells in a mouse model.


METHODS
Twenty-four athymic nude mice were inoculated with human prostate carcinoma cells from the PC-3 cell line. Twelve mice (experimental group) received injections of 1.6 micrograms of 16-23-D3 on alternate days over a 22-day period. Twelve mice (control group) received sham injections. Tumor volumes, pathologic findings, and terminal serum calcium levels were compared between groups.


RESULTS
The relative increase in tumor volume was significantly lower in the experimental than in the control group in the first interval following treatment (P < 0.01). Mean tumor volumes in the experimental group were approximately 15% smaller than in the control group. Serum calcium levels did not differ between groups.


CONCLUSIONS
16-23-D3 showed modest antiproliferative effects on prostate cancer cells in this model without evidence of drug-induced hypercalcemia. These findings support the concept that vitamin D analogues can inhibit the proliferation of human prostate cancer cells in vivo.
Schwartz
G G
GG
Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, Florida, USA.
Hill
C C
CC
Oeler
T A
TA
Becich
M J
MJ
Bahnson
R R
RR
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D002118:Calcium / Q000097:blood; D002455:Cell Division / Q000187:drug effects; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000187:drug effects / Q000473:pathology; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D010865:Pilot Projects; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D014407:Tumor Cells, Cultured / Q000637:transplantation
D000970:Antineoplastic Agents; D002117:Calcitriol; C064183:Ro 23-7553; D002118:Calcium