OBJECTIVETo establish an animal model of prostate cancer (PCa) metastasis to the lung using PCa PR7 (PCa PC-3 cells stably expressing red fluorescent protein AsRed2) cell lines that can be monitored by in vivo fluorescence imaging technology.

METHODSMTT and Transwell assay were used to compare the abilities of proliferation, migration and invasion of PC-3 and PR7 cells. Twenty BALB/c nude mice were equally randomized to 4 groups to receive tail vein injection of PR7 cell suspension at the concentration of 1 x 107/ml (group A), 2.5 x 107/ml (group B), 5 x 107/ml (group C) and 2.5 x 107/ml followed by the same dose 1 week later (group D). PCa metastasis to the lung was then monitored by in vivo fluorescence imaging technology at the end of 2, 4, 6 and 8 weeks.

RESULTSThere were no statistically significant differences between PC-3 and PR7 cells in their abilities of proliferation, migration and invasion (P > 0.05). At the end of 4 weeks, lung metastasis was observed in 40% of the mice in group D, and at the end of 8 weeks, it was detected in 20% in group A, 60% in group B, 100% in group C, and 100% in group D, all confirmed by pathological examination.

CONCLUSIONThe animal model of PCa metastasis to the lung that can be monitored by in vivo fluorescence imaging technology was established successfully by tail vein injection of PR7 cells carrying red fluorescent protein.