TP53 and lymphoma: The lymphoma cells were treated for 24 h with increasing concentrations of nutlin-3a, etoposide (a DNA damaging agent that causes activation of TP53/TRP53), and thapsigargin (induces apoptosis in a TP53/TRP53-independent manner by causing endoplasmic reticulum stress [34]) (Figs. 2C, S4B, C).