TNF-α induced cell death in nine sarcoma cell lines with different p53 status.

<p><i>A,</i> Western blot analysis of p53, MDM2 and p21 expression in <i>TP53^Wt</i>/<i>MDM2^Wt</i> (KYM-1 and HT1080), <i>TP53^Wt</i>/<i>MDM2^Ampl</i> (T449, T778 and T1000), <i>TP53^Mut</i> (MFH100 and MFH152) and <i>TP53^Null</i> (MFH95 and LMS148) cell lines studied after irradiation. Lysates were prepared 2 h after exposure to 15 Gy. <i>B</i>, Impact of TNF-α on cell survival assessed by DiOC₆/PI method after 72 h treatment. The percentage of specific apoptosis is shown as an increase of apoptotic cells (early and late apoptosis) in comparison to untreated cells. Results from four experiments are shown. *p<0.05 <i>versus</i> all cell lines. <i>C,</i> Cell surface expression of TNF receptor type 1 detected by flow cytometry following staining with TNFR1-specific monoclonal antibody (filled histograms) and isotype-matched control (open histograms). Percentages of positive cells and of mean fluorescence intensity are indicated; representative results from three experiments are shown.