Ming Hong

Aberrant microRNA expression in Chinese patients with chronic lymphocytic leukemia

MicroRNAs (miRNAs) are a class of small endogenous RNAs that play important regulatory roles by targeting mRNAs for cleavage or translational repression. Many reports have indicated that miRNAs play a critical role in malignancies, and regulations in the progression of leukemia. However, the miRNAs expression level in Chinese patients with chronic lymphocytic leukemia (CLL), and its prognostic value remain elusive. We identified various degrees of down-regulation of miR-15a, miR-16-1, miR-29b, miR-181a and miR-181b in CLL mononuclear cells. Moreover, we have identified miR-29b and miR-181a/b expression significantly correlated with IGHV mutational status. Transcript levels of predicted target genes BCL-2 and TCL-1 were also determined, and the expression levels were significantly upregulated in CLL patients compared with normal controls (P<0.001). Higher expression of TCL-1 was significantly correlated with aggressive disease features. In addition, an inverse correlation was observed in the CLL samples we examined between miRNAs (miR-16-1, miR-181a, miR-181b) and BCL-2 level; furthermore, an inverse correlation was also observed between miRNAs (miR-16-1, miR-181a, miR-181b) and TCL-1, which suggest that these miRNAs may implicate in negatively regulating target mRNA at transcriptional level. These different miRNAs may play an important role in the pathogenesis of CLL and might be applied for the assessment of prognosis in patients with CLL.

Cotransplantation of HLA-identical mesenchymal stem cells and hematopoietic stem cells in Chinese patients with hematologic diseases

Mesenchymal stem cells (MSCs) may be employed to support hematopoietic reconstitution and mitigate graft‐vs.‐host disease (GVHD) in transplantation of hematopoietic stem cells (HSCs). The aim of this study was to explore the feasibility and safety of cotransplantation culture‐expanded MSCs and HSCs from the same human leukocyte antigen (HLA)‐identical sibling donor in Chinese patients with hematologic diseases. Bone marrow mononuclear cells from healthy donors were cultured and expanded ex vivo. Immunophenotype, adipogenic and osteogenic differentiation potential, and karyotype of the harvested MSCs were detected on those who had been cotransplanted with HSCs and MSCs from the same donor. Hematopoietic reconstitutions, complications, and clinical outcomes were observed after cotransplantation in these patients. (1.77 ± 0.40) × 106/kg (donor’s weight) MSCs were successfully expanded from 23.6 ± 5.96 ml of bone marrow samples. They had normal karyotypes with bi‐lineages differentiation potential, and were CD73, CD90, and CD105 positive. Twelve patients underwent cotransplantation with no observable adverse response during and after the infusion of MSCs. Hematopoietic reconstitutions were rapid. Two patients developed grade II–IV acute GVHD, and two extensive chronic GVHD. Four patients suffered from cytomegalovirus infection but were cured eventually. Up to now, seven patients have been followed as long as 29–57 months and five patients died. It is concluded that MSCs can be expanded effectively by culture and it is safe and feasible to cotransplant patients with allogenic culture‐expanded MSCs and HSCs.

Clinical significance of down-regulated cylindromatosis gene in chronic lymphocytic leukemia.

Abstract Loss of cylindromatosis gene (CYLD) expression has been observed in various cancers, including chronic lymphocytic leukemia (CLL). As a deubiquitination enzyme, CYLD regulates the proliferation, development and activation of lymphoid cells. Here we determined the CYLD mRNA expression by quantitative polymerase chain reaction (PCR) in 125 patients with CLL. CYLD was considerably down-regulated in CLL cells compared to normal B cells. Low CYLD expression was associated with unmutated status of the immunoglobulin heavy-chain variable-region (IGHV) gene (p = 0.0018) and CD38 positivity (p = 0.0499). Patients with high CYLD expression showed a trend toward improved overall survival (OS) (10-year OS: CYLD high: 94.74%, CYLD low: 52.71%; p = 0.0534). For patients with mutated IGHV gene, high CYLD was also associated with better OS (10-year OS: CYLD high: 100%, CYLD low: 66.67%; p = 0.0547). In conclusion, low CYLD expression identifies a subgroup of patients with CLL with inferior outcome, indicating the role of CYLD as a tumor suppressor in the pathogenesis of CLL.

TIGAR cooperated with glycolysis to inhibit the apoptosis of leukemia cells and associated with poor prognosis in patients with cytogenetically normal acute myeloid leukemia

BackgroundCancer cells show increased glycolysis and take advantage of this metabolic pathway to generate ATP. The TP53-induced glycolysis and apoptosis regulator (TIGAR) inhibits aerobic glycolysis and protects tumor cells from intracellular reactive oxygen species (ROS)-associated apoptosis. However, the function of TIGAR in glycolysis and survival of acute myeloid leukemia cells remains unclear.MethodsWe analyzed TIGAR expression in cytogenetically normal (CN-) AML patients and the correlations with clinical and biological parameters. In vivo and in vitro, we tested whether glycolysis may induce TIGAR expression and evaluated the combination effect of glycolysis inhibitor and TIGAR knockdown on human leukemia cell proliferation.ResultsHigh TIGAR expression was an independent predictor of poor survival and high incidence of relapse in adult patients with CN-AML. TIGAR also showed high expression in multiple human leukemia cell lines and knockdown of TIGAR activated glycolysis through PFKFB3 upregulation in human leukemia cells. Knockdown of TIGAR inhibited the proliferation of human leukemia cells and sensitized leukemia cells to glycolysis inhibitor both in vitro and in vivo. Furthermore, TIGAR knockdown in combination with glycolysis inhibitor 2-DG led leukemia cells to apoptosis. In addition, the p53 activator Nutlin-3α showed a significant combinational effect with TIGAR knockdown in leukemia cells. However, TIGAR expression and its anti-apoptotic effects were uncoupled from overexpression of exogenous p53 in leukemia cells.ConclusionsTIGAR might be a predictor of poor survival and high incidence of relapse in AML patients, and the combination of TIGAR inhibitors with anti-glycolytic agents may be novel therapies for the future clinical use in AML patients.

Heterogeneous leukemic clones identified by NPM1 mutation analysis in patient with acute monocytic leukemia

Abstract NPM1 mutation is the most common molecular abnormality in patients with acute myeloid leukemia (AML), especially normal karyotype AML (NK-AML), and is associated with a favorable prognosis in the absence of concomitant FLT3-ITD. Like other molecular abnormalities such as FLT3-ITD, C/EBPα and c-Kit mutation, NPM1 mutation normally presents as a recurrent molecular abnormality. The NPM1 mutation is generally used as a molecular marker in the prognosis evaluation of a patient with AML. Here, we report a different case. He was first diagnosed with NPM1 mutation-positive acute monocytic leukemia. However, he achieved no remission, but the NPM1 mutation dramatically became negative after induction chemotherapy. Finally, he achieved complete remission after salvage chemotherapy and the NPM1 mutation was still negative. To our knowledge, this is a rare case according to the worldwide published literature.

Polymorphisms and haplotypes in multidrug resistance 1 gene are not associated with chronic lymphocytic leukemia susceptibility and prognostic parameters of chronic lymphocytic leukemia in Chinese population

The human multidrug resistance (MDR1, ABCB1) gene encodes P-glycoprotein (P-gp), which affects the pharmacokinetics of many drugs. Here, we investigated whether common MDR1 single nucleotide polymorphisms (SNPs) (C1236T, C3435T, and G2677T/A) affect predisposition to chronic lymphocytic leukemia (CLL). Genotyping was performed in 150 patients with CLL and 117 controls using polymerase chain reaction (PCR)-based assays. Haplotypes were inferred using the PHASE algorithm. We found comparable allele and genotype frequencies among patients with CLL and controls. Moreover, patient and control groups did not differ regarding MDR1 haplotype distribution (p = 0.97). Furthermore, no correlation was shown between the MDR1 1236, 3435, or 2677 genotypes and Binet stage, unmutated immunoglobulin heavy-chain variable region (IGHV) status, CD38 expression, ZAP-70 expression, and p53 deletion. In conclusion, our results do not support a major influence of MDR1 variants on the risk of CLL, and these genomic polymorphisms are not associated with clinical prognostic factors in Chinese patients with CLL.

A Case of Ulcerative Colitis Associated With Autoimmune Hemolytic Anemia Successfully Treated by Autologous Hematopoietic Stem Cell Transplantation

A Case of Ulcerative Colitis Associated With Autoimmune Hemolytic Anemia Successfully Treated by Autologous Hematopoietic Stem Cell Transplantation

High-dose methylprednisolone can induce remissions in patients with fludarabine-refractory chronic lymphocytic leukaemia.

PURPOSE To evaluate the clinical efficacy and safety of high-dose methylprednisolone (HDMP) in patients with fludarabine-refractory chronic lymphocytic leukaemia (CLL). METHODS Twelve patients who were refractory to fludarabine-based treatment were treated with 2-6 cycles of HDMP (1g/m(2) for 5days). RESULTS Ten patients (83.3%) responded to treatment and three (25.0%) achieved a complete remission (CR). Two (16.7%) of which had no evidence of minimal residual disease (MRD) after treatment. Patients with leukaemia cells that have high expression of ZAP-70 or CD38, unmutated immunoglobulin heavy chain variable region (IGHV), mutated p53 or adverse cytogenetic features achieved response to treatment at rates that appeared similar to those achieved by patients who did not have such disease characteristics. With a median follow-up of 13 (4-30) months, the median overall survival (OS) and the progression-free survival (PFS) have not been achieved. Treatment with HDMP was well tolerated, notably in the patients having poor myeloid reserve and pretreated cytopaenias. CONCLUSIONS HDMP is an effective non-myelotoxic regimen for the treatment of patients with fludarabine-refractory CLL.

The combination therapy of imatinib and dasatinib achieves longterm molecular response in two imatinib-resistant and dasatinibintolerant patients with advanced chronic myeloid leukemia.

For patients with chronic myeloid leukemia (CML) failing imatinib therapy, second-generation tyrosine kinase inhibitors (TKIs) are recommended. Here, we describe two patients with advanced CML who failed imatinib therapy and did not tolerate the recommended dose of dasatinib, but then achieved a major molecular response with the combination of imatinib and dasatinib with no significant extramedullary toxicity. Our observations suggest that combination of TKIs may provide an additive/synergistic antileukemic effect.

The synergy of Vitamin C with decitabine activates TET2 in leukemic cells and significantly improves overall survival in elderly patients with acute myeloid leukemia

BACKGROUND Decitabine is widely used in the treatment of acute myeloid leukemia (AML) in elderly patients. Low-dose Vitamin C has also been indicated to induce DNA demethylation at the cellular level. However, little is known whether low-dose Vitamin C has a synergistic effect with decitabine in clinic. METHODS The effect of combined low-dose Vitamin C and decitabine on cell proliferation, the cell cycle, apoptosis and the expression level and activity of TET2 was investigated in HL60 and NB4 human leukemic cells. Additionally, we analyzed the clinical outcomes of 73 elderly AML patients who received A-DCAG (intravenous Vitamin C [IVC] plus DCAG [n = 39]) or DCAG (n = 34) treatment. RESULTS We found that low-dose Vitamin C and decitabine has a synergistic efficacy on proliferation, apoptosis, TET2 expression and activity, compared to drug-alone treatment in HL60 and NB4 cell lines in vitro. In clinic, feasibility and safety evaluations revealed that patients who received A-DCAG regimen have a higher complete remission (CR) rate than those who received the DCAG regimen (79.92% vs. 44.11%; P = 0.004) after one cycle of chemotherapy. The median overall survival (OS) was better in the A-DCAG group compared with the DCAG group (15.3 months vs. 9.3 months, P = 0.039). Patients with adverse cytogenetics did benefit from CR. There was no clinically significant additional toxicity observed with the addition of IVC. CONCLUSION On the basis of these results, the addition of IVC at low doses to DCAG appeared to improve CR and prolong OS, compared with DCAG, in elderly patients with AML.