Bcl-2-ASO potentiates down-regulation of Bcl-2 in DEX-treated freshly isolated myeloma cells.

Cells were treated as detailed in the footnote to Table1. The results obtained from flow-sorted myeloma cells in 6 MM patients (patients M1, M2, M3, M5, M6, and M9) outlined in Table 1 are presented. Apoptosis (B), Bcl-2 expression (C), and quantitation of Bcl-2 bands by densitometry (A) were determined in the same experiment. Note that in 3 of 6 cases, treatment with Bcl-2-ASO (AS) alone induced high levels of apoptosis with extensive down-regulation of Bcl-2 comparable or higher than DEX alone (DEX). However, the combination of both drugs (AS+DEX) resulted in all cases with additional decrease in Bcl-2 protein and additional increase in apoptosis. Also, in all cases tested, the observed decrease in Bcl-2 inversely correlated with the extent of apoptosis (A-C). “C” in panel C indicates control. Twenty-five micrograms of protein were loaded onto each gel. For further details, see the legend to Figure 1 and “Materials and methods.”