Figure 8

CXCR7 knockdown leads to a reduction in CXCR4 protein levels in LNCaP cells. (A) Transwell assay assessing the effects of CXCL12 on LNCaP migration. ANOVA was used to determine significant differences between vehicle (0.1% BSA) and CXCL12-treated cells (*p ≤ 0.05, n = 3). (B) Transwell assay assessing the effects of CXCR4 and CXCR7 knockdown on CXCL12-induced LNCaP cell migration. LNCaP cells transfected with 100 nM scrambled control, CXCR4, or CXCR7 siRNAs were seeded to the top chamber of the insert. The bottom chamber contained medium with 1% CS serum with 1 nM R1881 and CXCL12 at 0, 0.003, 0.03, or 0.3 nM concentrations. Data was normalized to control siRNA transfected, vehicle-treated cells. ANOVA was used to determine significant differences (*p ≤ 0.05, n = 3) between control and experimental cells. (C-E) Western blots to test the effects of CXCR7 and CXCR4 knockdown on AR signaling in LNCaP cells. Cells were transfected with control, CXCR7 or CXCR4 siRNA for 72 hrs and probed with antibodies against (C) CXCR7, (D) CXCR4, (E) AR, and PSA. The densitometry values were normalized to control siRNA transfected cells and labeled below the blots. (F) Silver staining demonstrates equivalent loading across the samples.