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Many European groups have recently described that mutations at exon-12 of the nucleophosmin (NPM1) gene are the most frequent genetic lesion in patients with acute myeloid leukemia (AML), especially in the presence of a normal karyotype. This study explored the prevalence and clinical profile of NPM1 mutations in a cohort of 156 Chinese adults with AML. NPM1 exon-12 mutations were detected using direct sequencing or fragment analysis of genomic DNA polymerase chain reaction products. NPM1 mutations were present in 28.2% of the overall population, including 1/1 (100%) of M0, 11/27 (40.7%) of M1, 11/46 (23.9%) of M2, 0/29 (0%) of M3, 2/9 (22.2%) of M4, 18/39 (46.2%) of M5, and 1/5 (20.0%) of M6. NPM1 gene mutations were more prevalent in patients with a normal karyotype (37 of 90; 41.1%) when compared with patients with karyotypic abnormalities (7 of 66; 10.6%;P < .001). Sequence analysis of 25 NPM1-mutated cases revealed known mutations (type A, D, N(M), and P(M)) as well as one novel sequence variation (here named as type S). All mutational types were heterozygous and showed a 4 bp insertion. NPM1 mutations were significantly associated with old age (P < .05), high peripheral white blood cell count (P < .05), and the subtypes of French-American-British categories M1/M5, but negatively associated with expression of CD34 (P < .05) and CD117 (P < .05). Thus, this study provides the methods of NPM1 exon-12 mutations detection and related clinical data of NPM1 mutated cases in a Chinese population. [ABSTRACT FROM AUTHOR]

This study reports 10 patients with hematological malignances with t(20;21)(q11;q11) resulting from del(20q) (for example, der(20)del(20)(q11q13)t(20;21)(q11;q11) and der(21)t(20;21)(q11;q11)) and described their clinical features and the possible prognostic significance of this abnormality. The t(20;21)(q11;q11) was a rare but recurrent abnormality secondary to del(20q) besides i(20q-). The frequency of der(20)del(20)(q11q13)t(20;21)(q11;q11) among our patients with del(20q) was 2.4%. It was considered that the 20q deletion preceded translocation with chromosome 21. This abnormality is often cryptic, occurs predominantly in older men and is observed most often in myelodysplastic syndromes. Patients with this abnormality have an unfavorable prognosis, similar to patients with i(20q-). The molecular consequences of der(20)del(20)(q11q13)t(20;21)(q11;q11) may be different from patients with i(20q-). To the best of our knowledge this is the largest dataset published to date. [ABSTRACT FROM AUTHOR]

Abstract: A pericentric inv(9)(p22q34) of the derivative chromosome 9 that resulted from a standard t(9;22)(q34;q11.2) was identified by R-banding karyotypic analysis and fluorescence in situ hybridization (FISH) assays in 4 (0.18%) of 2,200 Philadelphia chromosome (Ph)-positive leukemia patients, including 3 with chronic myeloid leukemia (CML) in chronic phase and 1 with acute myeloid leukemia (AML) in our hospital since 2004. All four patients had two malignant clones: one with only t(9;22)(q34;q11.2) and another with der(9)t(9;22)(q34;q11.2)inv(9)(p22q34) that resulted in the separation of the ABL1/BCR fusion gene. No metaphases with only inv(9)(p22q34) were seen in any of them. FISH also found a deletion of partial sequence of BCR on der(9)t(9;22)(q34;q11.2)inv(9)(p22q34) in 67.5% of bone marrow cells in the AML patient, but did not detect the deletion of the sequence of ASS/9q34 in these four patients. Reverse transcriptase–polymerase chain reaction revealed a b3a2 type of BCR/ABL1 fusion transcript in all of them, proving their disease to be Ph-positive leukemia. On reviewing the literature, only two solitary Ph-positive leukemia patients have been noticed to have the inv(9)(p22q34) anomaly. These two patients, together with our four documented patients, indicate that inv(9)(p22q34) is a novel, rare, but recurrent secondary chromosomal abnormality for Ph-positive leukemia. Despite receiving hydroxyurea therapy (n = 3 patients), combined chemotherapy (n = 2), even imatinib treatment (n = 1), three patients, including one with AML and two with CML (one of whom progressed into the lymphoblastic blast phase), died with survival times of 28 days, 13 months, and 34 months, respectively. Only one patient with CML remained alive for 5.5 months. Their negative outcome implies that inv(9)(p22q34) has an unfavorable impact on prognosis. Presently, no firm conclusions can be drawn from this study. Because the case number reported here is very small, more patients with this anomaly need to be investigated to elucidate its true prognostic significance. [Copyright &y& Elsevier]

Abstract: To date, at least 25 translocations involving the NUP98 gene and different partner genes have been reported in the literature. Here, we describe a novel reciprocal t(5;11)(q31;p15) involving NUP98, as revealed by conventional karyotypic analysis using R-banding technique and fluorescence in situ hybridization (FISH) using a BAC RP11-120E20 probe and whole chromosome paint probes for chromosomes 5 and 11 in a 77-year-old woman who was diagnosed as having de novo acute myeloid leukemia. The patient received two courses of intensive combined chemotherapy but did not reach complete remission. She eventually died from the progressive disease, surviving for only 1 month after diagnosis. FISH analysis using WCP5 together with BAC RP11-878F9 or RP11-155N22 demonstrated that the breakpoint of chromosome 5 is located on 5q31. In addition, the EGR1 gene was unexpectedly found to be lost in the FISH study using EGR1 (red)/D5S23, D5S721 (green) dual-color probe. We supposed that the fusion gene created by t(5;11)(q31;p15) consisting of the NUP98 and its partner gene, as well as the loss of the EGR1 gene, may play a cooperative role in leukemogenesis. The partner gene of NUP98 in t(5;11)(q31;p15) is unclear at this time. Further molecular study is required to identify this partner gene in our patient. [Copyright &y& Elsevier]

Abstract: Besides cytopenia, dysplasia is crucial characteristic of MDS-RA. To summarize the morphological features that contribute to the diagnosis of MDS-RA, 48 RA patients with abnormal karyotype were analyzed for the features of morphological and cytogenetical abnormalities and the relationships between them. 46 MDS-RA patients with normal karyotype and 207 patients with non-MDS anemia were enrolled into control groups. More conspicuous and diverse dysplasia can be found in abnormal karyotype MDS-RA than those in control groups (P <0.05). Apparent dysplasia in granulocyte and megakaryocytoid lineages may provide valuable evidence for the diagnosis. Dysplasia occurred more frequently in patients with severe chromosome abnormalities. [Copyright &y& Elsevier]

Abstract: Translocation (14;14)(q11;q32) is one of the recurrent chromosome aberrations in ataxia-teleangiectasia (AT) and T-cell malignancies. In patients with the t(14;14), the TCL1 and TCRα/δ genes were found to be involved at the molecular level. However, t(14;14)(q11;q32) is an exceedingly rare phenomenon in B-lineage acute lymphoblastic leukemia (B-ALL). To date, it has been reported in only 5 B-ALL cases. Here, we report another B-ALL case with t(14;14)(q11;q32) in a 39-year-old female. The immunophenotype of the blasts showed positivity for CD79a, CD10, CD19, and HLA-DR. Chromosome analysis of the bone marrow (BM) cells at presentation showed the karyotype 47,XX,+4,t(14;14)(q11;q32). Fluorescence in situ hybridization (FISH) demonstrated trisomy 4 and the simultaneous involvement of the IGH gene at 14q32 and the CEBPE gene at 14q11, which differs from the genes involved in T-cell leukemias. After chemotherapy, the patient achieved complete remission (CR). Later, she received allogeneic peripheral blood stem cell transplantation. After CR, the karyotype of the BM cells was normal. She was disease-free at a 6-month follow-up. We suggest that t(14;14)(q11;q32) involving the IGH and CEBPE genes in B-ALL is rare, but it is a recurrent abnormality that could identify a new subgroup of B-ALL. [Copyright &y& Elsevier]

A rare chromosomal translocation, (11;20)(p15;q11), was detected in a 29-year-old male patient diagnosed with acute monocytic leukemia (AMoL) according to the French–American–British classification criteria. Whole chromosome painting analysis with paints for chromosomes 11 and 20 confirmed the result of conventional cytogenetic analysis. Reverse transcriptase polymerase chain reaction revealed the NUP98-TOP1 fusion transcript. To our knowledge, this is the second report of the translocation involving NUP98 and TOP1 genes in AMoL. On reviewing the literature, we suggest that t(11;20)(p15;q11) is associated with myelocytic disorders rather than lymphocytic proliferative diseases. [Copyright &y& Elsevier]