p27 protein is down-regulated in the Fli-3–infected cells. (A) Protein isolated from NIH-3T3 cells infected with either Fli-3-mir-17–92, Fli-3-mir-92, or empty vector was subjected to Western blot analysis using p27 antibody. The intensity of NIH3T3 band was used as control (1.0). (B,C) RNA isolated from NIH-3T3 cells or HB60–5 cells infected with either Fli-3-mir-17–92, Fli-3-mir-92, or vector was subjected to PCR analysis using the primers for both p27 and GAPDH. The intensity of NIH3T3 (B) or HB60–5 vector (C) band was used as control (1.0). Mean fold changes are shown at the bottom. (D) RNA isolated from NIH-3T3 cells and HB60–5 cells infected with either Fli-3-mir-17–92, Fli-3-mir-92, or vector control was subjected to real-time PCR analysis using the primers for both p27 and GAPDH. The expression of p27 in HB60–5 cells was used for calibration. Error bars are SD.