title: Restoration of nonclonal hematopoiesis in chronic myelogenous leukemia (CML) following a chemotherapy-induced loss of the Ph1 chromosome.
abstract: After intensive chemotherapy, marrow cells of some patients with Philadelphia chromosome (Ph1) positive chronic myelogenous leukemia (CML) become partially or completely Ph1-negative. However, without a second marker for the neoplastic clone, it could not be determined if these Ph1-negative cells arose from normal progenitors or were still members of an abnormal clone. In the present study, a patient with Ph1-positive CML, also heterozygous for glucose-6-phosphate dehydrogenase (G6PD), was studied before and after intensive chemotherapy. Prior to treatment only G6PD type B was detected in the patient's red cells, platelets, and granulocytes, and all unstimulated marrow metaphases had Ph1. After four cycles of chemotherapy, 76% of marrow cells were Ph1-negative, and approximately 80% of the granulocytes were nonclonal by G6PD analysis. Thus, the frequency of nonclonal cells by G6PD analysis correlated closely with that of the Ph1-negative cells. The data indicate that intensive chemotherapy can restore nonclonal and presumably non-neoplastic hematopoiesis in CML.
mesh_terms: D000328:Adult; D002869:Chromosome Aberrations; D002904:Chromosomes, Human, 21-22 and Y / Q000648:ultrastructure*; D002999:Clone Cells; D003561:Cytarabine / Q000627:therapeutic use; D003630:Daunorubicin / Q000627:therapeutic use; D005260:Female; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007621:Karyotyping; D007951:Leukemia, Myeloid / Q000188:drug therapy / Q000235:genetics*; D013866:Thioguanine / Q000627:therapeutic use
chemical_list: D003561:Cytarabine; D005954:Glucosephosphate Dehydrogenase; D013866:Thioguanine; D003630:Daunorubicin