Figure 4.

A, Whole cell lysates from human prostate stromal cells (60 μg) and T47D breast cancer cells (5 μg) were separated on a protein gel and Western blotted with antibodies against PR, α-SMA, and vimentin. Vinculin and β-actin levels were used as loading controls. B, One million WPMY-1 cells were recombined with 0.5 million BPH-1 cells and grafted under renal capsule in SCID mice for 2 or 4 weeks (n = 3/time point). Xenograft tissues were fixed and immunostained with PR (SP2) antibody. Note that SP2 antibody only recognizes PR protein from human or rat. C and D, WPMY-1 and CAF cells were infected with lentivirus to express mock, PRA, or PRB. Cells were maintained in phenol red free medium containing 10% charcoal stripped serum for 48 hours and then seeded in 96-well culture plates for proliferation assay over 0–8 days. E, Human primary cultured HPS-19I cells were transiently infected with lentivirus encoding mock, PRA, or PRB. Cells were then seeded in 96-well culture plates in the presence of −/+ 10 nm P4. Cell proliferation rates were measured over 0–16 days.