ABSTRACT
Objective To analyze the influence of SH3 domain mutant (ABL SH3-T79Y) in BCR-ABL protein of chronic myeloid leukemia (CML) in combination with imatinib (IM) on the proliferation of CML cells in vivo and vitro, and to discuss the mechanism thereof. Methods Recombinant ABL SH3-T79Y mutant adenovirus vectors which were successfully constructed in previous work was used with IM to treat K562/G01 cells, then the cell-colony forming ability of K562/G01 cells was determined by clone formation assay, and cell cycle was assessed by flow cytometry. KCL22 cells were treated by recombinant SH3-T79Y and IM to construct subcutaneous solid tumor model in Balb/c nude mice, then the formation rate of subcutaneous tumor was estimated, the pathological examination was conducted, and the proliferation ability of KCL22 cells was assayed. K562/G01 cells were treated by SH3-T79Y and IM in combination, and the expression levels of p-BCR-ABL, BCR-ABL, p-CrkL, CrkL and Cyclin-D1 protein were determined by Western blotting. Cells treated with PBS, null recombinant adenovirus vectors or IM alone served as control groups. Results Compared to the 3 control groups, clone forming rate of K562/G01 cells decreased significantly (P<0.05) and cell cycles were arrested at S phase after being combined SH3-T79Y and IM treatment. The subcutaneous solid tumor formation rate in KCL22- Balb/c nude mice was 16.7% after combined SH3-T79Y and IM treatment, and large number of tumor cells were observed in tumor pathology examination. Western blotting revealed that the expression levels of p-BCR-ABL, p-CrkL, BCR-ABL, CrkL and Cyclin-D1 were decreased in K562/G01 cells. Conclusion Combined treatment of SH3-T79Y and imatinib may inhibit the proliferation of CML cells in vivo and in vitro by decreasing BCR-ABL and CrkL phosphorylation as well as Cyclin-D1 protein.
ABSTRACT
BACKGROUND: The coexistence of t(9;22)(q34;q11.2) and inv(16)(p13q22) chromosomal abnormalities is extremely uncommon, and only a small number of such cases have been reported. Here, we characterized 7 cases of hematologic malignancy exhibiting t(9;22) and inv(16) coexistence. METHODS: We reviewed the cytogenetic data for hematologic malignancies treated at the Catholic Blood and Marrow Transplantation Center between January 2004 and June 2013. We identified 7 cases exhibiting t(9;22) and inv(16) coexistence. In addition, we analyzed mutations in the IKZF1, NPM1, FLT3, N-RAS, K-RAS, c-KIT, and TP53 genes. RESULTS: Four cases of chronic myelogenous leukemia (CML; 1 chronic phase, 2 accelerated phase, and 1 blast phase) and 3 cases of acute myeloid leukemia (AML; 1 de novo and 2 therapy-related) were identified. The percentages of circulating blasts and bone marrow eosinophils were higher in AML cases than in CML cases (53% vs. 5% and 30% vs. 5.5%, respectively). The proportions of each chromosomal abnormality were used along with follow-up karyotyping results to identify secondary changes. In BCR/ABL, a p210 fusion transcript was associated with CML, whereas a p190 fusion transcript was associated with AML. One patient with AML harbored 2 mutations: c-KIT D816V and TP53 E11Q. All patients except 1 with CML blast phase sustained clinical remission after treatment, which included an imatinib mesylate regimen. CONCLUSION: This study shows that observations of bone marrow morphology, initial and follow-up cytogenetic studies, and karyotyping of BCR/ABL1 and CBFB/MYH11 provide valuable information for characterizing hematologic malignancies exhibiting t(9;22) and inv(16) coexistence.
Subject(s)
Humans , Blast Crisis , Bone Marrow , Chromosome Aberrations , Cytogenetics , Eosinophils , Follow-Up Studies , Genes, p53 , Hematologic Neoplasms , Karyotyping , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Leukemia, Myeloid, Acute , Mesylates , Imatinib MesylateABSTRACT
We report a case of chronic myelogenous leukemia displaying a variant Philadelphia translocation t(11;22)(q25;q11.2). Breakpoint 11q25 has not previously been reported. Reverse transcriptase polymerase chain reaction and fluorescence in-situ hybridization demonstrated the BCR/ABL rearrangement.
Subject(s)
Fluorescence , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
The erythroleukemic blast crisis in chronic myelogenous leukemia (CML) is rarely reported. We present two cases of erythroleukemic blast crisis of CML. In both cases, they had been treated with interferon and hydroxyurea prior to a blast crisis of CML. On blastic transformation, one patient underwent an acute clinical transformation marked with fever and hematochezia but the other showed no clinical deterioration. The blasts appeared in the peripheral blood. The bone marrow aspirates revealed megaloblastic erythroid hyperplasia (about 72%, 54% of all nucleated cells), increasing the number of myeloblasts (about 46%, 59% of all non-erythroid cells), and erythroblasts with a positive PAS stain. The cytogenetic studies revealed Philadelphia chromosomes with additional chromosomal abnormalities, t(3;21)(q26;q22) and the FISH studies revealed bcr-abl fusion signals in bone marrow cells. One case expired 8 months later despite of hydroxyuria therapy. The other case received allogeneic bone marrow transplantation (alloBMT) without complete remission but expired 34 weeks after alloBMT due to GVHD.