Blocking FGF9 reduced osteoblastic bone metastases in mice, according to a paper in The JCI.
A protein called FGF9 plays an important role in the metastasis of prostate cancer to the bones, according to researchers at The University of Texas M. D. Anderson Cancer Center.
The team used two prostate cancer cell lines derived from the bones of an individual with osteoblastic bone metastases. Both cell lines lacked expression of androgen receptors to mimic tumors that have developed the ability to grow in the absence of this hormone.
These androgen receptor-negative prostate cancer cell lines grew when transplanted into immunocompromised mice and generated osteoblastic bone metastases, the scientists report. FGF9 was expressed at higher levels in these cells lines than in other bone-derived prostate cancer cells and induced bone formation in an in vitro organ culture assay. Additionally, blocking FGF9 reduced osteoblastic bone metastases in mice transplanted with the cell lines.
The M.D. Anderson group also found that FGF9 was expressed in 24 of 56 primary tumors derived from human organ-confined prostate cancer and in 25 of 25 bone metastasis cases.
These results appear online on July 10 in The Journal of Clinical Investigation.