Animal models and drug administration
Male BALB/c nude mice (6-8 week-old) were provided by Jiangsu
Gempharmatech co. Ltd. (Nanjing, China). The mice were kept under
pathogen-free conditions in type IV Makrolon cages (6 mice per cage) in
an air flow cabinet at 23°C, 12 h/12 h day/night cycle. Sterilized food
and sterilized acidified water have been provided to the animals
regularly. 1×106 LNCaP and PC3/AR+cells were injected subcutaneously into the right flank. After 6 days of
injection, all mice formed tumors and the day was marked as day 0.
Vehicle (0.05% DMSO in PBS), 10 and 30 µg/kg SBF-1 were
intraperitoneally injected to every group respectively every day since
day 0 for 45 days. At the same time, body weights and tumor volumes were
measured. For tumor growth assay, mice were euthanized 14 days after
drug treatment, and the weight of tumor was measured. Animal welfare and
experimental procedures were carried out in accordance with the Guide
for the Care and Use of Laboratory Animals (Ministry of Science and
Technology of China, 2006) and the related ethical regulations of
Nanjing University. All efforts were made to minimize animals’ suffering
and to reduce the number of animals used.