FIG. 5.

MPA induces Stat3 nuclear translocation. C4HD cells were treated with 10 nM MPA for the time indicated or were pretreated with PP2 before MPA stimulation. Nuclear (nuc) and cytosolic (cyt) fractions were prepared, and 30 μg of protein from cell extracts was analyzed by Western blot assay for Stat3 expression level. Membranes were then stripped and hybridized with an anti-p85 PI-3K subunit antibody (middle) or an anti-retinoblastoma (Rb) antibody (bottom) in order to control cellular fractionation efficiency. W, Western blot assay.