radiography of tibiae xenografted with PC-3 or PC-3/Fluc cells at day 28 after intra-osseous inoculation. B. Expression of noggin, Dkk-1, PTHrP, RANKL, CSF-1 and IL-8 mRNA. mRNA expression levels (+/2 SD) are quantified by real-time RT-PCR and normalized to b-actin as endogenous control. mRNA expression level in PC-3 cells is set as 100%; the mean of 2 to 3 independent experiments is shown. ***P,0.001, PC-3/Fluc versus PC-3 cells. (TIF) Figure S2 Noggin silencing promotes increase in radio- density in advanced osteolytic lesions. Radiographic aspect of sham-operated and cancer cell-xenografted tibiae at day 21 after intra-osseous inoculation. (TIF) Figure S3 Noggin silencing promotes partial bone repair in advanced osteolytic lesions and limits late tumor growth. A. Radiographic aspect and B. 3-D reconstruc- tion (m-CT) of tibiae xenografted with PC-3/Fluc and Nog-KD clones, at day 23 (PC-3/Fluc), day 30 (Nog-KD 17) and day 33 (Nog-KD 14) after inoculation. C. Growth in vivo of PC-3/Fluc and Nog-KD clones. Bioluminescent signal (photon counts +/2 SD) emitted from the cancer cell-xenografted tibiae was quantified at day 7, 14, 21, 23, 28, 30 and 33 after intra-osseous implantation of tumor cells; n = 6–7 animals for each experimental group. ***P,0.001, Nog-KD clones versus PC-3/Fluc at day 21. (TIF) References 1. Bubendorf L, Schopfer A, Wagner U, Sauter G, Moch H, et al. (2000) Metastatic patterns of prostate cancer: an autopsy study of 1,589 patients. Hum Pathol 31: 578–583. 2. Roudier MP, True LD, Higano CS, Vesselle H, Ellis W, et al. (2003) Phenotypic heterogeneity of end-stage prostate carcinoma metastatic to bone. Hum Pathol 34: 646–653. 3. Kozlow W, Guise TA (2005) Breast cancer metastasis to bone: mechanisms of osteolysis and implications for therapy. J Mammary Gland Biol Neoplasia 10: 169–180. 4. Lage MJ, Barber BL, Harrison DJ, Jun S (2008) The cost of treating skeletal- related events in patients with prostate cancer. 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