Thymidine-phosphorothioate oligonucleotides induce activation and apoptosis of CLL cells independently of CpG motifs or BCL-2 gene interference.
We compared antisense phosphorothioate oligonucleotides (PS-ODN) that target BCL-2 such as Genasense (G3139-PS), with other PS-ODN or phosphodiester-ODN (PO-ODN) in their relative capacity to induce apoptosis of chronic lymphocytic leukemia (CLL) B cells in vitro. Surprisingly, we found that thymidine-containing PS-ODN, but not PO-ODN, induced activation and apoptosis of CLL cells independent of BCL-2 antisense sequence or CpG motifs. All tested thimidine-containing PS-ODN, irrespective of their primary sequences, reduced the expression of Bcl-2 protein and increased the levels of the proapoptotic molecules p53, Bid, Bax in CLL cells. Apoptosis induced by thymidine-containing PS-ODN was preceded by cellular activation, could be blocked by the tyrosine-kinase inhibitor imatinib mesylate (Gleevec), and was dependent on ABL kinase. We conclude that thymidine-containing PS-ODN can activate CLL cells and induce apoptosis via a mechanism that is independent of BCL-2 gene interference or CpG motifs.
Castro
J E
JE
John and Rebecca Moores Cancer Center, University of California San Diego, La Jolla, CA, USA.
Prada
C E
CE
Aguillon
R A
RA
Kitada
S
S
Fukuda
T
T
Motta
M
M
Wu
C
C
Dicker
F
F
Sun
G
G
Wang
J Y J
JY
Carson
D A
DA
Reed
J C
JC
Kipps
T J
TJ
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D001402:B-Lymphocytes / Q000187:drug effects*; D051023:BH3 Interacting Domain Death Agonist Protein / Q000187:drug effects / Q000378:metabolism; D001549:Benzamides; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D018899:CpG Islands / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D004354:Drug Screening Assays, Antitumor; D004789:Enzyme Activation / Q000187:drug effects; D019254:Genes, bcl-2 / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D006801:Humans; D000068877:Imatinib Mesylate; D066298:In Vitro Techniques; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000378:metabolism*; D009838:Oligodeoxyribonucleotides / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000494:pharmacology*; D009946:Organothiophosphorus Compounds / Q000737:chemistry / Q000494:pharmacology*; D010766:Phosphorylation; D010879:Piperazines / Q000494:pharmacology; D016315:Proto-Oncogene Proteins c-abl / Q000187:drug effects / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology; D013329:Structure-Activity Relationship; D013936:Thymidine / Q000737:chemistry* / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000378:metabolism; D015854:Up-Regulation
D000590:Amino Acid Chloromethyl Ketones; D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; D001549:Benzamides; D009838:Oligodeoxyribonucleotides; D009946:Organothiophosphorus Compounds; D010879:Piperazines; D011743:Pyrimidines; D016159:Tumor Suppressor Protein p53; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D000068877:Imatinib Mesylate; D016315:Proto-Oncogene Proteins c-abl; D020169:Caspases; D013936:Thymidine