Fig 7. TNF-R1 (A), CD95 (B) and TRAIL-R1 (C) expression, caspase-8 (D) and caspase-3 (E) activities and cell proliferation (F) in transfected HepG2 and Hep3B cells with TAp63α, ΔNp63α, TAp73α and ΔNp73α overexpressing plasmids.

The parameters were assessed 48 hours after cell transfections. The protein expression of cell death receptors was assessed by western-blot analysis following the procedure described in Material and Methods. Caspase-8 and -3 activities were determined using commercial assays described in Material and Methods. Cell proliferation was determined by BrdU incorporation administered 2 hours before cell collection following the procedure described in Material and Methods. Data are expressed as mean ± SEM either from the densitometry analysis of blots referred to the corresponding loading control (stain-free procedure) or to caspase activity referred to a calibration curve developed using recombinant purified enzyme. The asterisks indicate statistical significance (*p≤0.05, **p≤0.01 or ***p≤0.001) compared with their corresponding empty vector transfected cell line. The groups denoted by different letters (a, b, c or d) are significantly different among them (p≤0.05).