Figure 4

MSCs promoted the transformation of LNCaP cells via TGF-β.

We employed siRNA to block the expression of TGF-β in MSCs. (A) LNCaP cells and MSCs^si-TGF-β were prepared either as single-cell type suspensions (1 × 10⁶ LNCaP cells in 200 μL PBS) or a mix of cells (1 × 10⁶ LNCaP cells and 2 × 10⁵ MSCs^si-TGF-β in 200 μL PBS). LNCaP cells (alone or mixed with MSCs) were subcutaneously administrated in the armpit area of castrated nude mice. (B) LNCaP cells were pretreated with conditioned medium (CM^si-TGF-β) collected from MSCs^si-TGF-β for 5 days and then subcutaneously administrated in the armpit area of castrated nude mice. On 70 day after implantation, the animals were sacrificed and tumor volume was evaluated by measuring the length and width of tumor mass. (C,D) pretreated with CMsi-TGF-β in an androgen-deprivation (AD) condition (*P < 0.05).