Figure 4.
Dose and time dependent of PPP down-regulated IGF-1R proteins in drug resistant osteosarcoma cells. U-2OSMR was treated with PPP in dose (A) or time (B) dependent manner in fresh complete medium. Total cellular proteins were subjected to immunoblotting with specific antibodies to IGF-1R, pIGF-1R, AKT and β-actin as described in “Materials and Methods”. A: PPP reduces IGF-1R proteins in U-2OSMR cells as dose dependent manner. U-2OSMR cells were cultured for 24 h in the presence of various concentrations of PPP as indicated. B: U-2OSMR cells were cultured for the time indicated (in hours) in the presence of 1 μM of PPP. C and D: Western blots from A and B were analyzed using densitometry as described in “Materials and Methods”.