A, Human prostate tissue microarrays (TMAs) from The Tissue Core of the University of Michigan Comprehensive Cancer Center and US Biomax Inc., were stained for CXCL12γ (red) or pan-cytokeratin (green). Cells expressing both markers are indicated with white arrows. DAPI nuclear stain (blue). Bar=50μm. TMAs consist of normal prostate tissues (n=8), benign (n=6), Gleason 6–7 prostate cancer tissues (n=12), Gleason 9–10 prostate cancer tissues (n=25). B, Quantification of Fig. 1A. C, Human prostate metastatic tissues from The Tissue Core of the University of Michigan Comprehensive Cancer Center were stained for CXCL12γ (red) or pan-cytokeratin (green). Metastatic tissues are lymph node (n=15), lung (n=10), liver (n=12), and bone (N=19). D, Quantification of Fig. 1C. E, Left panel: CXCL12γ (red) expression in pan-cytokeratin (green) expressing prostate adenocarcinoma in human bone tissue as detected by immunofluorescence staining, and the magnification of the yellow rectangle from left panel. Bar=20–50μm. Right panel: CXCL12 γ (red) expression in pan-cytokeratin (green) expressing a small cell carcinoma phenotype in human bone tissue as detected by immunofluorescence staining, and the magnification of the yellow rectangle from right panel (white arrows). Bar=20–50μm. F, mRNA expression of CXCL12γ in CSCs (CD133+/CD44+) or non-CSCs (CD133-/CD44-) from LNCaP cells or a castration-resistant sub-line of the LNCaP cells, LNCaP95 as quantified by real-time PCR. G, mRNA expression of CXCL12γ in CSCs (CD133+/CD44+) or non-CSCs (CD133-/CD44-) from the metastatic cell lines PC3 and DU145 as quantified by real-time PCR. Data in Fig. 1B, 1D, 1F, and 1G are representative of mean ± SD (Student’s t-test).