Anti-prostate cancer activity of 8-hydroxyquinoline-2-carboxaldehyde-thiosemicarbazide copper complexes in vivo by bioluminescence imaging.

Copper 8-hydroxyquinoline-2-carboxaldehyde-thiosemicarbazide complex (CuHQTS) is a copper complex with strong anticancer activity against cisplatin-resistant neuroblastoma and prostate cancer cells in vitro by cell proliferation assay or fluorescent microscopic imaging. This study aimed to evaluate anti-prostate cancer activity of CuHQTS in vivo by bioluminescence imaging (BLI) and tumor size measurement, using athymic nu/nu mice implanted with prostate cancer cells carrying luciferase reporter gene (Luc-PC3). Growth of Luc-PC3 cells (1 × 105 cells) implanted in athymic nu/nu mice treated with CuHQTS for 2 weeks was suppressed by measurement of luciferase signals (6.18 × 107 to 5.36 × 107 p/s/cm2/sr) with BLI, compared with luciferase signals of Luc-PC3 cells (4.66 × 107 to 1.51 × 108 p/s/cm2/sr, p < 0.05) in the mice treated with normal saline of placebo control. Moreover, the size of PC-3 xenograft tumor (126.5 ± 34.2 mm3) in athymic nu/nu mice treated with CuHQTS was significantly smaller than the size of PC-3 xenograft tumor (218.6 ± 48.0 mm3, p < 0.05) in athymic nu/nu mice treated with normal saline of placebo control, suggesting in vivo tumor growth inhibition activity of CuHQTS on prostate cancer. The findings of this study support further investigation of CuHQTS as a promising new anticancer agent for the treatment of metastatic prostate cancer refractory to anticancer drugs currently available.