Fig. 4.

Loss of JNK promotes proliferation of immature ΔPten prostate cells. (A) The cloning efficiency of Sca1⁺ cells isolated from ΔPten and ΔPten ΔJnk prostate tumors was measured at passage 2 in vitro. Equal numbers of Sca1⁺ cells were plated and the number of prostaspheres obtained after 14 d in culture was examined (mean ± SD; n = 3). Significant differences are indicated (*P < 0.05). (B) Sections of prostaspheres were stained for DNA (DAPI) and the stem cell markers p63 and nucleostemin (NS). (C and D) Sections of prostaspheres were stained with H&E or with DNA (DAPI) plus basal (CK5) and luminal (CK8) differentiation markers.