Abrupt decrease of c-myc expression by antisense transcripts induces terminal differentiation and apoptosis in human promyelocytic leukemia HL-60 cells

摘要

This study was designed using c-myc antisense transcripts to evaluate how alteration of c-myc expression in human myeloid leukemic HL-60 cells could influence the myelomonocytic differentiation and induction of apoptosis. The recombinant plasmid pDACx expressing antisense transcripts to c-myc fragment containing a part of intron 1 and 137 nt exon 2 was constructed. pDACx was transfected into HL-60 cell line by lipofectin reagent.Cytochemical stainings including NBT reduction, peroxidase and α -NAE as well as detection of CD13 and CD33 antigens by flow cytometric analysis indicated occurrence of myelomonocytic differentiation in cells expressing antisense transcripts to c-myc. DNA degradation measured by DNA gel electrophoresis and typical morphological changes observed under electron microscope proved the switchon of apoptosis in terminally differentiating HL-60 cells.