Erten C.Karaca B.Kucukzeybek Y.Gorumlu G.Cengiz E.Gul M.K.Atmaca H.Uzunoglu S.Karabulut B.Sanli U.A.Uslu R.2025-04-102025-04-102009http://hdl.handle.net/20.500.14701/51518OBJECTIVE To evaluate the effects of combined treatment with docetaxel and octreotide, a somatostatin analogue, on human hormone- and drug-refractory prostate cancer cell lines, PC-3 and DU-145, and on some growth factors related to tumour growth and angiogenesis in prostate cancer. MATERIALS AND METHODS A cell proliferation assay was used to assess the cytotoxicity of the drugs. To verify apoptosis, both DNA fragmentation (by enzyme-linked immunosorbent assay) and caspase 3/7 activity were measured. We also investigated the effect of combined docetaxel and octreotide on growth factors secreted from prostate cancer cells using a human growth factor antibody array. RESULTS The combination of docetaxel and octreotide resulted in significant synergistic cytotoxic activity and apoptosis, which was dose- and time-dependent. The combined treatment also resulted in significantly less secretion of stem cell factor and platelet-derived growth factor-AB in PC-3 cells, and transforming growth factor-β and basic fibroblast growth factor in DU-145 cells, than in untreated controls. CONCLUSION Octreotide, a somatostatin analogue, combined with docetaxel might provide a rationale treatment option for hormone-refractory prostate cancer cells, not only by direct inhibition of cell proliferation but also by inhibiting the secretion of growth factors. © 2009 BJU International.Article10.1111/j.1464-410X.2009.08340.x