Analysis of Wip1 mRNA expression in Tax-expressing and Tax-non-expressing cells. (A) Total RNAs from HTLV-1–transformed MT-2, MT4, C8166 T-cell lines and HTLV-1-negative CD4+ control T-cell lines (Jurkat, CEM, and H9) were extracted and reverse transcribed. The cDNAs were used for real-time RT-PCR analyses of Wip1, Tax, and GAPDH (internal standard) transcripts. The mRNA relative expression levels of Wip1 and Tax mRNA were determined and normalized as multiples of the GAPDH mRNA. The columns represent the average results from 3 experiments; the error bars are mean errors. (B) Real-time RT-PCR analyses of Wip1 and GAPDH (internal control) transcripts were performed in p53−/− HCT116, (C) p53+/+ HCT116 and (D) HeLa cells after transfection with a control vector or a Tax-expression vector. To detect Tax protein, immunoblots were stained using Tax and α-tubulin specific monoclonal antibodies. Tubulin was used as a loading control.