c-myc and c-fos expression during interferon-alpha therapy for hairy cell leukemia.
Low-dose interferon-alpha (IFN-alpha) therapy is consistently effective in the treatment of hairy cell leukemia (HCL). In two cases of resistance to IFN-alpha administration, we diagnosed variant HCL, a form of HCL with intermediate features between typical HCL and B cell prolymphocytic leukemia. We tried to distinguish variant and typical hairy cells (HCs) by Northern blot analysis of the oncogenes expressed in vivo. We report that variant HCs contain c-myc transcripts in contrast to typical HCs, whereas c-fos transcripts are detected in both cell types. We also report that the mRNA levels of c-myc are not modified in variant HCs by IFN-alpha treatment, whereas the level of c-fos mRNA is modulated in both types of HCs. Our findings suggest that the failure to modulate c-myc expression in vivo might indicate the limits of low-dose IFN-alpha therapy.
D002453:Cell Cycle; D005786:Gene Expression Regulation; D006801:Humans; D007167:Immunotherapy; D007370:Interferon Type I / Q000627:therapeutic use*; D007943:Leukemia, Hairy Cell / Q000235:genetics / Q000628:therapy*; D009698:Nucleoproteins / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics
D007370:Interferon Type I; D009698:Nucleoproteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm