20-hydroxyvitamin D₃ inhibits proliferation of cancer cells with high efficacy while being non-toxic.

AIM

To define the potential utility of 20-hydroxyvitamin D(3) (20(OH)D(3)) as a tumorostatic agent, we assessed its in vitro antiproliferative activity and its in vivo toxicity.

MATERIALS AND METHODS

The antitumor activity of 20(OH)D(3) was tested against breast and liver cancer cell lines using colony formation assays. To assess in vivo toxicity, mice were injected with 5-30 μg/kg 20(OH)D(3) intraperitoneally each day for 3 weeks. Blood and organ samples were collected for clinical pathology analyses.

RESULTS

20(OH)D(3) displays similar tumorostatic activity towards MDA-MB-453 and MCF7 breast carcinomas, and HepG2 hepatocarcinoma, in a dose-dependent manner. This compound is not hypercalcemic, does not cause detectable toxicities in liver, kidney, or blood chemistry in mice at a dose as high as 30 μg/kg. In contrast, both 25(OH)D(3) and 1,25(OH)(2)D(3) caused severe hypercalcemia at a dose of 2 μg/kg.

CONCLUSION

20(OH)D(3) possesses high efficacy for inhibiting cancer cell proliferation in vitro and is non-toxic in vivo, supporting its further development as a potential anticancer therapeutic agent.