[Effects of PML and PML-RAR alpha antisense oligonucleotides on promyelocytic leukemia cell line NB4].
OBJECTIVE
To investigate the different effects of anti-PML (promyelocytic leukemia) and anti-PML/RAR alpha (promyelocytic leukemia/retionic acid receptor alpha) antisense oligonucleotides on cell growth, expression of PML-RAR alpha mRNA and PML-RAR alpha/PML protein location of NB4 cell line.


METHODS
RT-PCR was used for PML-RAR alpha mRNA expression, trypan blue exclusion for cell count, methylcellulose assay for leukemic colony forming unit, immuno-fluorescence for PML-RAR alpha/PML protein localization.


RESULTS
Both anti-PML start codon region antisense (STAS) and anti-PML-RAR alpha fusion region antisense (FUAS) could inhibit cell growth and formation AML-CFU. Cells became partially differentiated on day 5, being more marked in FUAS-treated cells than in STAS-treated ones. Down regulated PML-RAR alpha mRNA expression occurred at 24 h was in STAS and FUAS-treated cells and maintained for up to 72 h. Immuno-fluorescence analysis with anti-PML monoclonal antibody showed a remarkable decrease to almost complete disappearance of microgranules. The residual granules became enlarged to become discrete dots (< 10 per cell), similar to normal POD structure in some STAS-treated cells at 24 h. AT 72 h, nearly all the granules disappeared. Similar changes were observed in FUAS-treated cells.


CONCLUSIONS
Both PML and PML-RAR alpha antisense oligonucleotides can specifically block the expression of PML-RAR alpha at mRNA and protein levels. PML protein is implicated in the regulation of cell differentiation.
Chen
Y
Y
Shanghai Institute of Hematology, Renji Hospital, Laboratory of Leukemia Research, Shanghai Second Medical University, Shanghai 200001, China.
Miao
J
J
Fang
Z
Z
D002455:Cell Division / Q000187:drug effects; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000473:pathology*; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D000071156:Promyelocytic Leukemia Protein; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D000072482:Retinoic Acid Receptor alpha; D014157:Transcription Factors / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014410:Tumor Stem Cell Assay; D025521:Tumor Suppressor Proteins
D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D016376:Oligonucleotides, Antisense; D000071156:Promyelocytic Leukemia Protein; C000607071:RARA protein, human; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D000072482:Retinoic Acid Receptor alpha; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human