Caspase 3 activity was measured in T47D cells stably transduced with MLV-HA-RASSF1C (T47D-RASSF1C). The T47D cells treated with doxycycline (D) and/or 45 um/ml etoposide (E) for 48 hr. Cells were subsequently assayed for caspase 3 activity. RASSF1C over-expression down regulates the expression of caspase 3 and hence less caspase 3 activity is observed in T47D-1C cells treated with both D and E compared to cells treated with E alone (p < 0.01). Data normalized to T47D cells that were treated with vehicle and the assay was carried at least three independent times with N = 4.