Effects of 3-deazaadenosine on apoptosis-related gene transcripts in HL-60 cells.
The effect of the transmethylation inhibitor 3-deazaadenosine on transcription levels of genes associated with apoptosis was investigated in HL-60 cells. After incubation of HL-60 cells with 100 microM 3-deazaadenosine for 45 min., a schedule known to perturb transmethylation metabolites and initiate apoptosis in these cells, a 50% decrease in c-myc and a 50% increase in bcl-2 RNA steady-state levels compared to control cells were observed. Transcription levels of c-myc continued to decrease after extended exposure to 3-deazaadenosine, while bcl-2 mRNA levels dropped to 25% and 30% below those in control cells after 1.5 hr and 3 hr, respectively. The expression levels of the bcl-2 related bax gene, showed a similar pattern as bcl-2; a 60% increase was initially measured, but after 1.5 and 3 hr, bax transcripts were 80% and 70% respectively, of those found in untreated cells. Another bcl-2 related gene, bcl-x, was previously reported to generate two transcripts in human cells. The long variant bcl-x1 acts as bcl-2, while the short form bcl-xs induces apoptosis. We were unable to detect bcl-xs transcripts in untreated and 3-deazaadenosine treated cells by the highly sensitive reverse transcriptase polymerase chain reaction method. This suggests that this gene product may not be involved in 3-deazaadenosine induced apoptosis in HL-60 cells. Bcl-x1 mRNA levels, however, slowly decreased with about 50% after 1.5 or 3 hr 3-deazaadenosine treatment. It is concluded that 3-deazaadenosine initiated apoptosis affects c-myc, bcl-2, bax and bcl-x1 mRNA levels.
Loennechen
T
T
Department of Pharmacy, University of Tromsø, Norway.
Moens
U
U
Kildalsen
H
H
Andersen
A
A
Rekvig
O P
OP
Aarbakke
J
J
D017209:Apoptosis / Q000235:genetics*; D015870:Gene Expression / Q000187:drug effects*; D019254:Genes, bcl-2 / Q000187:drug effects*; D016259:Genes, myc / Q000187:drug effects*; D018922:HL-60 Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D011518:Proto-Oncogene Proteins / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D014372:Tubercidin / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D051028:bcl-2-Associated X Protein; C018258:3-deazaadenosine; D014372:Tubercidin