Chronic clonal myeloproliferative disease associated with a t(5;21) translocation. Complete but transient hematologic and cytogenetic remission induced by interferon-alpha.
A patient with a chronic myeloproliferative disease associated with a 100% t(5;12) translocation was treated with 3 million U per day of IFN-alpha 2a. Besides being consistently Ph-negative, the search for BCR/ABL hybrid transcripts by means of RT-PCR was also negative. Total cytogenetic conversion to diploid hematopoiesis was obtained, but after discontinuation of IFN a 50% relapse of t(5;21) mitoses was found, and treatment was resumed. There is some degree of consensus that the mechanism by which IFN-alpha suppresses the Ph+ clone in CML consists in the restoration of normal adhesion of CML progenitors to the marrow stroma, by preventing transcription of the BCR/ABL mRNA, and hence expression of the p210 tyrosine kinase. However, if the 'faulty adhesion' hypothesis, and its correction by IFN-alpha, is to be considered correct, this case proves that it must include also Ph-negative, not BCR-ABL rearranged clonal myeloid proliferations.
Marmont
A M
AM
Division of Hematology, Ospedale S Martino, Genoa, Italy.
Sessarego
M
M
D000328:Adult; D001853:Bone Marrow / Q000473:pathology*; D002448:Cell Adhesion; D002874:Chromosome Mapping; D002891:Chromosomes, Human, Pair 21; D002895:Chromosomes, Human, Pair 5; D005500:Follow-Up Studies; D016044:Fusion Proteins, bcr-abl / Q000096:biosynthesis; D015321:Gene Rearrangement; D006412:Hematopoietic Stem Cells / Q000378:metabolism / Q000473:pathology; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use*; D007621:Karyotyping; D008297:Male; D009196:Myeloproliferative Disorders / Q000097:blood / Q000235:genetics* / Q000628:therapy*; D011994:Recombinant Proteins; D012074:Remission Induction; D013997:Time Factors; D014158:Transcription, Genetic; D014178:Translocation, Genetic
D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D016044:Fusion Proteins, bcr-abl