Zhimei Chen

Clinical and cytogenetic features of 508 Chinese patients with myelodysplastic syndrome and comparison with those in Western countries

Myelodysplastic syndrome (MDS) is a clonal hematopoietic stem cell disorder characterized by ineffective hematopoiesis and leukemia progression. Racial differences may exist on clinical pictures and the molecular events leading to MDS, which are heterogeneous. To better define the clinical and cytogenetic features in Chinese patients, a retrospective multicentric study was performed in 508 MDS cases. Compared with Western countries, Chinese patients showed younger age (median: 49 vs 65–73 years), lower percentages of RARS (2.8 vs 6.6–15.3%), and CMML (5.2 vs 11.7–30.6%). Cytogenetically, among 367 cases with evaluable data, abnormal karyotypes were found in 136 cases, including 56 numerical and 80 structural changes. Incidences of single chromosome 5 and 7 abnormalities were lower than those in Western countries (2.2 vs 17.8–42.5%). However, complex cytogenetic aberrations and chromosome translocations were frequently observed and related to poor prognosis. Both multiple chromosome deletions and translocations were detected in advanced subtypes (RAEB and RAEB-T). Analysis of 200 cases revealed a higher incidence of hepatitis-B-virus infection than that in non-MDS population (21.00 vs 9.75%). This study further confirmed: (1) different genetic/environmental backgrounds between Asian and Western MDS populations; (2) a strong predictive value of cytogenetic abnormalities on disease outcome and involvement of genomic instability in leukemia clone development.

The proteasome inhibitor bortezomib interacts synergistically with the histone deacetylase inhibitor suberoylanilide hydroxamic acid to induce T-leukemia/lymphoma cells apoptosis

Interactions between inhibitors of the proteasome and histone deacetylases have been examined in human T-leukemia/lymphoma cells both in vitro and in vivo. Co-exposure of cells to bortezomib and suberoylanilide hydroxamic acid (SAHA) synergistically induces T-leukemia/lymphoma cells to undergo apoptosis, consistent with a significant increase in mitochondrial injury and caspase activation. These events are accompanied by inhibition of cyto-protective signaling pathways, including the nuclear factor (NF)-κB, Raf-1/mitogen-induced extracellular kinase (MEK)/extracellular signal-related kinase (ERK) and AKT pathways, and activation of stress-related cascades, including the stress-activated kinases c-jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK). Moreover, bortezomib in conjunction with SAHA efficiently induces apoptosis of primary T-leukemia/lymphoma cells and inhibits tumor growth in a murine xenograft model established with subcutaneous injection of Jurkat cells. Taken together, these findings confirm the synergistic anti-tumor effect of the proteasome and histone deacetylase inhibitors, and provide an insight into the future clinical applications of bortezomib–SAHA combining regimen in treating T-cell malignancies.

Homoharringtonine in combination with cytarabine and aclarubicin resulted in high complete remission rate after the first induction therapy in patients with de novo acute myeloid leukemia.

To assess the efficacy and toxicity of HAA regimen (homoharritonine 4u2009mg/m2/day, days 1–3; cytarabine 150u2009mg/m2/day, days 1–7; aclarubicin 12u2009mg/m2/day, days 1–7) as an induction therapy in the treatment of de novo acute myeloid leukemia (AML), 48 patients with newly diagnosed AML, aged 35 (14–57) years, were entered into this clinical study. The median follow-up was 26 months. Eighty-three percent of patients achieved complete remission (CR), and the first single course of induction HAA regimen resulted in CR rate of 79%. The CR rate of 100, 82 and 33% were achieved in patients with favorable, intermediate and unfavorable cytogenetics, respectively. For all patients who achieved CR, the median time from the initiation of the induction therapy to the evaluation of the remission status was 32 days. For all patients, the estimated 3 years overall survival (OS) rate was 53%, whereas for patients with M5, the estimated OS rate at 3 years was 75%. The toxicities associated with HAA regimen were acceptable, and the most common toxicity was infection. This study suggested that HAA regimen might be a well-tolerable, effective induction regimen in young adult patients with AML.

Cytogenetic profile of de novo acute myeloid leukemia: a study based on 1432 patients in a single institution of China

Geographic heterogeneity of cytogenetic patterns in hematological malignancies has been reported earlier, but few systematic studies of cytogenetic abnormalities in acute myeloid leukemia (AML) patients are available. We examined the karyotypic patterns in 1432 de novo AML patients from a single center in China and compared our data with reports from other regions of the world. Chromosomal abnormalities were detected in 746 (58%) cases. The most frequent cytogenetic abnormality was t(15;17), detected in 14% of successful cases, followed by t(8;21) in 8%, and t(9;22), +21 and +8 each in 2%. The mean age of patients with a translocation karyotype was significantly younger than that of patients with normal, deletion or trisomy karyotypes. A higher incidence of AML M3 and a lower frequency of M4 were observed in the Asian population and the frequencies of certain cytogenetic aberrations were different from those in the earlier reports. Population-based age-specific incidences of AML were calculated and compared with those in western reports.

FLT3 and NPM1 mutations in Chinese patients with acute myeloid leukemia and normal cytogenetics

Mutations of fms-like tyrosine kinase 3 (FLT3) and nucleophosmin (NPM1) exon 12 genes are the most common abnormalities in adult acute myeloid leukemia (AML) with normal cytogenetics. To assess the prognostic impact of the two gene mutations in Chinese AML patients, we used multiplex polymerase chain reaction (PCR) and capillary electrophoresis to screen 76 AML patients with normal cytogenetics for mutations in FLT3 internal tandem duplication (FLT3/ITD) and exon 12 of the NPM1 gene. FLT3/ITD mutation was detected in 15 (19.7%) of 76 subjects, and NPM1 mutation in 20 (26.3%) subjects. Seven (9.2%) cases were positive for both FLT3/ITD and NPM1 mutations. Significantly more FLT3/ITD aberration was detected in subjects with French-American-British (FAB) M1 (42.8%). NPM1 mutation was frequently detected in subjects with M5 (47.1%) and infrequently in subjects with M2 (11.1%). FLT3 and NPM1 mutations were significantly associated with a higher white blood cell count in peripheral blood and a lower CD34 antigen expression, but not age, sex, or platelet count. Statistical analysis revealed that the FLT3/ITDpositive group had a lower complete remission (CR) rate (53.3% vs. 83.6%). Survival analysis showed that the FLT3/ITD-positive/NPM1 mutation-negative group had worse overall survival (OS) and relapse-free survival (RFS). The FLT3/ITD-positive/NPM1 mutation-positive group showed a trend towards favorable survival compared with the FLT3/ITD-positive/NPM1 mutation-negative group (P=0.069). Our results indicate that the FLT3/ITD mutation might be a prognostic factor for an unfavorable outcome in Chinese AML subjects with normal cytogenetics, while NPM1 mutation may be a favorable prognostic factor for OS and RFS in the presence of FLT3/ITD.

Characteristics and prognosis analysis of additional chromosome abnormalities in newly diagnosed acute promyelocytic leukemia treated with arsenic trioxide as the front-line therapy

Currently, there are few studies that address the prognostic significance of baseline additional chromosomal abnormalities (ACAs) in newly diagnosed acute promyelocytic leukemia (APL) patients treated with arsenic trioxide (ATO) as the front-line therapy. A series of 271 consecutive APL patients has been cytogenetically investigated between 2004 and 2011 in our institution. The incidence of ACAs was 27% (46/172) in APL cases with t(15;17). Trisomy 8 was the most recurrent abnormality, accounting for 30% (14/46) of patients with ACAs, followed by +21 (7%, 3/46) and -7/7q (7%, 3/46). Nine cases (14.1%) were found to have additional balanced translocation aberrations, most of them are new and non-recurrent. Treatment protocols consisted of all-trans retinoic acid (ATRA) and chemotherapy with or without the ATO therapy. Overall, patients with and without ACAs had similar complete remission (CR) rates (94% and 98%, respectively, P=0.344). With a median follow-up of 41 months, univariate analysis showed that ACAs did not show any prognostic significance in relapse-free survival (RFS) and overall survival (OS). In addition, ATO treatment was an independent favorable predictor for RFS. Thus, this data provides insights into cytogenetic features of APL, and suggests that ATO-based combination therapy improved RFS in de novo APL patients, while ACAs had no impact on prognosis.

Cytogenetic profile of 1,863 Ph/BCR-ABL-positive chronic myelogenous leukemia patients from the Chinese population

Cytogenetic analyses of chronic myelogenous leukemia (CML) have been performed previously in a large number of reports, but systematical research based on large sample sizes from the Chinese population is seldom available. In this study, we analyzed the cytogenetic profiles of 1,863 Philadelphia (Ph)/BCR-ABL-positive CML patients from a research center in China. Of 1,266 newly diagnosed CML patients, the median age was 41xa0years, which is younger than the median age of diagnosis in western populations. The incidence of additional chromosome abnormalities (ACA) was 3.1% in newly diagnosed chronic phase (CP), 9.1% in CP after therapy, 35.4% in accelerated phase, and 52.9% in blast crisis (BC), reflecting cytogenetic evolution with CML progression. A higher prevalence of ACA was observed in variant Ph translocations than in standard t(9;22) in the disease progression, especially in BC (88.2% vs. 50%, Pu2009=u20090.002). Moreover, a hyperdiploid karyotype and trisomy 8 were closely correlated with myeloid BC, while a hypodiploid karyotype and monosomy 7 were associated with lymphoid-BC. Among subsets of myeloid-BC, myeloid-BC with minimal differentiation had a higher ACA rate than myeloid-BC with granulocytic differentiation (80% vs. 46.8%, Pu2009=u20090.009) and myeloid-BC with monocytic differentiation (80% vs. 42.9%, Pu2009=u20090.006). These data provide novel insights into cytogenetics of CML within the Chinese population.

Arsenic trioxide may improve the prognosis of APL with ider(17)(q10): report of a rare adult case of acute promyelocytic leukemia with ider(17)(q10)t(15;17) showing poor response to all-trans retinoic acid

Dear Editor, Acute promyelocytic leukemia (APL) is now considered a curable leukemia that is particularly sensitive to alltrans retinoic acid (ATRA) [1–3]. ider(17)(q10)t(15;17) (q22;q21) is a rare variant cytogenetic abnormality among APL patients, and its prognostic significance is still controversial [4–10]. We describe here a 58-year-old female with APL carrying ider(17)(q10)t(15;17). This patient presented with 1 week of fever. The result of the physical examination was normal. Complete blood count analysis showed a hemoglobin level of 91 g/L, white cell count of 1.9×10/L, and platelet count of 51×10/L. Coagulation studies revealed normal parameters. In flow cytometric analysis, the cells were positive for CD13 (75.48%), CD117 (49.16%), CD56 (96.1%), CD64s (87.66%), but negative for HLA-DR. Bone marrow examination showed 61% hypergranular promyelocytic blasts. The cytochemical staining showed the cells were positive for Sudan black B, peroxidase and myeloperoxidase, but negative for nonspecific esterase and the sodium fluoride inhibition test. FISH analysis showed a variant fusion pattern with one PML signals (red), one RARA signals (green), and three fusion signal (yellow) in 60% of the cells examined (Fig. 1). The karyotype was interpreted as 46,XX,der(15)t(15;17)(q22;q21),ider(17) (q10)t(15;17). A diagnosis of APL was made, and therapy was initiated with ATRA. On day 14 post-admission, however, the hypergranular promyelocytic blasts in bone marrow increased to 80.5%. Then idarubicin was added at day 15–17. On day 34 posttreatment of ATRA, the patient still failed to achieve remission. Then she received another induction treatment of arsenic trioxide (As2O3) for 21 days. The patient showed good response to As2O3, and a complete remission was established. Then the patient received consolidation chemotherapy for three courses during the next 23 months and remained in clinical remission up to now. Almost all the adult patients with ider(17)(q10) and available clinical data who did not die during induction therapy had a favorable response to ATRA [4–10], but in the present case, treatment with ATRA did not achieve the expected response. Even worse, the hypergranular promyelocytic blasts in the patient’s bone marrow increased continuously during the treatment of ATRA and remission was not achieved until after a course of As2O3 was given. Although it is reported that some relapse patients take more than 30 days to achieve complete remission (CR) under the treatment of ATRA, the duration of initial hospitalization was very short for patients who achieved CR, 3 to 20 days (median 8 days) [1]. Therefore, we consider that it is a clear APL case with ider(17)(q10) which respond worse to ATRA. Moreover, according to the review of the literature by Manola et al., patients with ider(17)(q10) who were not H. Tong (*) :K. Li : C. Mei : J. Jin Department of Hematology, the First Affiliated Hospital, Zhejiang University, College of Medicine, #79 Qingchun Road, Hangzhou, Zhejiang Province 310003, People’s Republic of China e-mail: hongyantong@yahoo.com.cn

t(X;17) as the sole karyotypic anomaly in a case of M3r subtype of acute promyelocytic leukemia without RARα rearrangement

We describe here a unique chromosomal abnormality found in a patient with M(3r) subtype of APL. Neither t(15;17) nor rearrangement of RARalpha was detected by routine R-banded chromosome as well as fluorescence in situ hybridization (FISH) analysis using PML/RARalpha dual-color dual-fusion translocation probe and RARalpha dual-color break apart rearrangement probe. Instead of the typical rearrangement between chromosomes 15 and 17, all cells analyzed had a translocation between X and 17 as the sole karyotypic anomaly. The translocation was conformed by whole chromosome painting (WCP) with painting probes of chromosomes X and 17. To our knowledge, this is the first documented APL with a novel translocation involving chromosomes X and 17 without RARalpha gene rearrangement.

Outcome prediction by the transcript level of BCR-ABL at 3 months in patients with chronic myeloid leukemia treated with imatinib--a single institution historical experience.

The BCR-ABL transcript level (≤ 10%) at 3 months after tyrosine kinase inhibitors can predict long term outcome in the patients with chronic myeloid leukemia in chronic phase (CML-CP). However, the significance of transcript level was still not determined in different risk groups of patients. A total of 299 patients with CML-CP were enrolled and stratified according to prior interferon-α (IFN) treatment, age, and interval time between diagnosis and imatinib treatment to investigate the prediction value of BCR-ABL transcript level for overall survival (OS), event-free survival (EFS), progression-free survival (PFS). Univariate and multivariate analysis proved that BCR-ABL transcript level at 3 months were associated with the treatment outcome. However, in the patients with prior IFN treatment, younger age, and longer interval between diagnosis and IM treatment, the predictive value of transcript value remain obscure in terms of EFS, PFS and OS, respectively, as well as cumulative incidence of PCyR, CCR, MMR and CMR. In conclusion, the transcript level of BCR-ABL at 3 months could serve as a predictive parameter, but should be used with caution.