Opg In Prostate Cancer Bone Metastases The Role Of Basic And Clinical Research

Purpose: To observe the secretion and effect of OPG in different kinds of prostatecancer cells. To evaluate the diagnostic usefulness of serum osteoprotegerin (OPG)in prostate cancer bone metastasis.Materials and Methods: After cultured for 48 hours, the concentration of OPG inPC₃ and LNCaP cells were measured. After 80% cell growth these two kinds of cellswere inculcated in 96-well plate for MTT test. 200ng/ml,20ng/ml and 2ng/ml ofOPG antibody were added into the PC₃ cells. 200ng/ml,20ng/ml and 2ng/ml ofOPG protein were added into the LNCaP cells. Serum osteoprotegerin weremeasured by ELISA assay in 30 healthy men, 30 patients with benign prostatichyperplasia, and 66 patients with prostate cancer, including 36 without bonemetastasis(30 with localized cancer, 6 with lymph node metastasis) and 30 with bonemetastasis. The results associated with clinical data were calculated statistically.Results: The androgen-independent human CaP cell line PC₃ produced relativelyhigh levels of secreted OPG protein in vitro, whereas the androgen-responsive cellline LNCaP produced low levels of OPG protein. The proliferation of cell line PC₃was depressed when decreasing the level of OPG in culture solution. The depressioneffect was positively associated with the level of OPG antibody, and there was asignificant difference between level of 200ng/ml and control, whereas the level ofOPG has no influence on the growth of cell line LNCaP. Serum osteoprotegerin weresignificantly increased in patients with bone metastasis, compared with others(P＜0.001). OPG level had a positive correlation with either PSA or ALP level (r=0.427,0.277;P＜0.001, =0.024); and a positive correlation with either Gleasonscore or grade (r=0.427,0.277;P＜0.001, =0.012). ROC analysis proved that OPGhad better diagnostic accuracy than ALP for detecting bone metastasis in prostatecancer.Conclusions: The androgen-independent human CaP cell line PC₃, which comes from the bone metastasis of CaP, produced relatively high levels of secreted OPGprotein in vitro. OPG may have a close relationship with the development of thebone metastasis in prostate cancer. Serum osteoprotegerin could be used as a markerfor diagnosis of bone metastasis in prostate cancer.