OBJECTIVETo establish a mouse model of spinal metastasis of human prostate cancer using fluorescence-labeled PC-3 cells to allow direct observation by in vivo imaging.

METHODSPC-3 cells were infected with a lentivirus carrying green fluorescence protein (GFP) gene. The GFP-positive cell clone was expanded and prepared into cell suspension for injection into the inferior vena cava of nude mice. The tumor growth and metastasis in the mice was directly observed using an in vivo fluorescence imaging system. The tumor-bearing mice were sacrificed after 3 months for histological examination with HE staining.

RESULTSThe labeled cells showed stable GFP expression both in vitro and in vivo. One week after cell injection, green fluorescence signals were detected by the in vivo fluorescence imaging system in the lower back of the mice, and at 4 weeks, the fluorescent tumor mass increased with a bone metastasis rate of 19% (3/16). Dissection of the mice at 3 months revealed lumbar tumor infiltration in 3 mice, showing a consistent result with in vivo fluorescence imaging.

CONCLUSIONThe nude mouse model of spinal bone metastasis of human prostate cancer established using GFP-labeled PC-3 cells facilitates further study of bone metastasis of prostate cancer.