ABSTRACT
DNA studies of the translocation t(15;17) in acute promyelocytic leukemia (APL) have shown that the retinoic acid receptor alpha (RARA) gene on chromosome 17 is juxtaposed to the promyelocytic leukemia (PML) gene on chromosome 15. The PML breakpoints have been mapped to 3 clusters: bcr1, bcr2, and bcr3. We have examined the PML breakpoint distribution in a series of 33 Chinese patients with APL. Twenty-two patients fell within bcr1, 2 within bcr2, and 9 within bcr3. The primary structure of the reciprocal chromosome translocation joints of one patient and that of their normal counterparts have been determined and compared to those of 2 previously reported cases. These studies revealed possible topoisomerase II cleavage sites close to the breakpoints and suggested implications of DNA attachment sites to nuclear matrix. We propose that these features are relevant to the process of illegitimate recombination generating the translocation.
Subject(s)
Carrier Proteins/genetics , Chromosomes, Human, Pair 15/ultrastructure , Chromosomes, Human, Pair 17/ultrastructure , Gene Rearrangement , Genes , Leukemia, Promyelocytic, Acute/genetics , Translocation, Genetic , Base Sequence , Consensus Sequence , DNA Mutational Analysis , DNA Topoisomerases, Type II/genetics , Humans , Introns , Molecular Sequence Data , Neoplasm Proteins/genetics , Receptors, Retinoic Acid , Recombinant Fusion Proteins/genetics , Sequence Homology, Nucleic Acid , Transcription Factors/geneticsABSTRACT
The configuration of the P53 tumor suppressor gene was investigated in 43 Chinese patients with chronic myelogenous leukemia (CML), 32 in chronic phase and 11 in blastic crisis. No obvious rearranged DNA band was detected in Southern blot patterns from patients at both stages of the disease. However, P53 gene deletion events were observed in 4 out of 11 cases in blast crisis. This finding was associated with a cytogenetically identifiable chromosome 17p deletion, iso(17q), in only one out of 4 cases.
Subject(s)
Blast Crisis/genetics , Chromosome Deletion , Genes, p53/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Adult , Aged , Alleles , Blotting, Southern , Child , China , Female , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Male , Middle AgedABSTRACT
In 100 cases with autoimmune hemolytic anemia, Coombs test was directly positive in 77 cases (77%). 82 patients had warm autoantibodies. IgM was increased in 12 patients. 3 patients were diagnosed as lymphoma with titers more than 1:1024. One patient had paroxysmal cold hemoglobinuria. The dramatic clinical response to corticosteroid therapy was observed in patients with warm autoantibodies. However, immunosuppressor should be given to patients with cold autoantibodies. It was suggested that combined therapy with two drugs may be more effective than the use of corticosteroid alone. Of 6 patients in whom splenectomy was performed, 4 showed excellent results. Out of 100 cases, there were 23 with Evans syndrome.
