Variations in c-Myc and p21WAF1 expression protect normal peripheral blood lymphocytes against BimEL-mediated cell death.

We have examined the effect of suberoylanilide hydroxamic acid (SAHA, Vorinostat, Zolinza) on the viability of normal peripheral blood lymphocytes (PBLs) in vitro and on the expression of 20 apoptosis-related genes. RT-PCR, western blots and flow cytometry were performed to reveal the proteins of apoptosis machinery that were affected to cause cell death. Our data suggest that PBL markedly resisted for approximately 24 h the destructive activity of the agent, but eventually 60% of cells treated with 4 micromol/L SAHA died within 72 h through mitochondrial way of apoptosis.

On the nucleolar and cytoplasmic RNA density during "cell dedifferentiation" represented by blastic transformation of human mature T lymphocytes - a cytochemical study.

The present study was undertaken to provide information on the nucleolar and cytoplasmic density in specimens stained for RNA during "cell dedifferentiation" represented by blastic transformation of mature T lymphocytes. Nucleolar and cytoplasmic RNA's were visualized using a simple cytochemical method followed by computer assisted densitometry and size measurements of digitised images. An increased nucleolar and cytoplasmic RNA density accompanying the blastic transformation was significant after 48 hours of cultivation with phytohemaglutinin (PHA) when stimulated cells were characterized the largest nucleolar size reflecting S or G2 phase of the cell cycle.

BimEL-dependent apoptosis induced in peripheral blood lymphocytes with n-butyric acid is moderated by variation in expression of c-myc and p21(WAF1).

We have examined the effect of sodium butyrate (SB) on the viability of normal peripheral blood lymphocytes (PBLs) in vitro and the effect of this agent on the expression of 20 apoptosis-related genes. Data suggest that PBL treated with 2 mmol L(-1) SB resisted for at least 8 h the destructive activity of the agent, but eventually 30% of cells died within 72 h. As documented by flow cytometry and cytochrome c release study, cells underwent mitochondrial-derived apoptosis.

Actinomycin D upregulates proapoptotic protein Puma and downregulates Bcl-2 mRNA in normal peripheral blood lymphocytes.

We have examined the ability of actinomycin D to induce apoptosis in human peripheral blood lymphocytes. Run-On assays were performed to specify the primary molecular damage, reverse transcription-PCR, Western blots and flow cytometry studies were performed to ascertain which proteins of the apoptosis machinery were affected to cause actinomycin D-induced cell death. Expression of 23 apoptosis-related genes was investigated.