A, TSG-6 staining in TRAMP tissue and TRAMP cell lines. A, TSG-6 staining in TRAMP tissue and TRAMP cell lines. Paraffin-embedded tissues sections were deparaffinized with xylene and rehydrated using graded ethanol and used in immunohistochemistry as described in Materials and Methods. i, no TSG-6 staining in the prostate from animal on normal diet. Magnification, ×40. ii, TSG-6 expression in prostate from a representative animal on 2-methoxyestradiol diet that showed positive staining. B, TSG-6 in TRAMP mouse prostate cancer cells. TRAMP C2, mouse prostate cells were either treated with 2-methoxyestradiol (3 μmol/L) for 24 hours or left untreated (solvent control). Following treatment, cells were harvested and fixed in 10% buffered formalin, and immunocytochemical analysis was done as described in Materials and Methods. Staining indicative of TSG-6 expression was detected only in cells treated with 2-methoxyestradiol. Untreated cells showed very little or no staining. C, Western blot analysis of TSG-6. TSG-6 expression was determined in TRAMP tumors (control) or prostate tissue (2-methoxyestradiol–fed animals) depending on the case using Western blot analysis. Data was quantified using Scion image analysis program. Gretchen E. Garcia et al. Clin Cancer Res 2006;12:980-988 ©2006 by American Association for Cancer Research