Focal lymphoblastic transformation of chronic myelogenous leukemia develops into erythroid leukemia:A case report

BACKGROUND We present a case of focal lymphoblastic transformation to erythroid leukemia following acute myeloblastic transformation in a patient with chronic myelogenous leukemia(CML)and discuss its mechanism of occurrence and development.CASE SUMMARY The presence of the Philadelphia(Ph)chromosome was identified through karyotype analysis,while the BCR-ABL fusion gene was detected using quantitative real-time polymerase chain reaction of the peripheral blood sample.Fluorescence in situ hybridization was used to detect the expression of the BCRABL gene in the lymphoma.Antigen expression and gene mutations in the primitive cells were detected by flow cytometry.The analysis confirmed the presence of CML along with focal lymphoblastic transformation to erythroid leukemia.Additionally,the patient was found to have secondary erythroid leukemia,along with multiple new gene mutations and abnormalities in complex karyotypes of chromosomes.CONCLUSION Our findings suggest a possible molecular basis for the focal lymphoblastic transformation secondary to myeloblastic transformation in patients with CML.

HIM_(1) AND HIM4, TWO MONOCLONAL ANTIBODIES POTENTIALLY USEFUL FOR AUTOLOGOUS BONE MARROW TRANSPLANTATION IN CHRONIC MYELOGENOUS LEUKEMIA

We developed two complement-fixing MoAbsHIMand HIM(murine)that were specifically reac-tive with chronic myelogenous leukemia (CML) cells.They were capable of fixing human or rabbit com-plement and suitable for CML cells purging of re-mission marrow from CML patients.HIMreactedwith majority leukemic cells form 7 out of 10 CMLpatients by complement-mediated cytotoxicity(C’MC)assay(positive cells 80%—90%),HIMreacted withmajority CML cells from 4 out of 5 CML by C’MCassay(positive cells 80%—90%).Treatment withHIMor HIMand human C’was capable of lysing97% of K562,U937,HL-60 and CML cells in a 20fold excess of unrelated cells by indirect FITC+EBstain.Using limited dilution culture,incubation withHIMand C’produced 1.5 logs inhibition of growthin K562 cells,and 1.9 logs in U937 cells,and withHIMand C’produced 2.9 logs inhibition in HL-60cells and 3.0 logs in U937 cells.Both MoAbs cocktailwas shown 1.8 logs in K562 cells and 3.2 logs in U937cells.They were no suppression on the growth o

Redistribution of Platelet Membrane Glycoprotein IV and Release of Intracellular α-granule Thrombospondin in Patients with Chronic Myelogenous Leukemia

The redistribution of platelet membrane glycoprotein IV (GPIV) and the release of intracellular Q-granule thrombospondin (TSP) were examined and the inhibition of 5-thromboglobulin (&TG) and platelet factor 4 (PF4) in patients with chronic myelogenous leukemia (CML) was observed and quantitation of β-TG and PF4 in sera was conducted. GPIV in inactive platelet from CML was 36080±17010 molecules/platelet as compared with 13190±4810 from the controls (P<0,01), No abnormality was found in the distribution of platelet membrane GPIb and GPIIb/III.(P>0. 05). The GPIV redistribution on active platelet membrane induced thrombin (1U/ml) from CML and healthy donors was 44320132310 and 228001 12700 molecules/platelet respectively (P<0. 01 ). The difference in the release of intracellular Q-granule TSP between CML and the control group was not found (P>0.05). There was no direct correlation between GPIV expression and TSP binding after platelet activation. The high leveIs of β-TG and PF4 in sera inhibited release of intracellular a-granule TSP in vitro. These results indicate that the abnormality of platelet membrane GPIV is a common marker in CML, therefore the specific increase of platelet GPIV in patients with CML may be a useful tool for the diagnosis and monitoring of the platelet dysfunction. The release of interna1 TSP pools is hindered by either β-TG or PF4 in sera.

Research on Marketing Strategies of Product D—a Chronic Myelogenous Leukemia Drug for Pharmaceutical Company A

Objective To put forward some suggestions on the marketing strategies for chronic myelogenous leukemia in a pharmaceutical enterprise.Methods Based on the development status of the pharmaceutical industry and the SWOT analysis of a company’s product,the marketing strategies were formulated to provide theoretical basis for pharmaceutical enterprise to adapt to the new medical reform.Results and Conclusion Nowadays,due to fierce competition,in order to expand the new market,enterprises should implement the strategies of new products,centralized management and professional training.Meanwhile,the effective marketing strategies should be formulated and strictly carried out according to the conditions of the pharmaceutical company.

High expression of RbAp46 gene in patients with acute leukemia or chronic myelogenous leukemia in blast crisis

The retinoblastoma （Rb） suppressor associated protein 46 （ RbAp46 ） also named retinoblastoma binding protein 7 （RBBP7） was first identified as a protein in HeLa cells that binds to an Rb affinity column. RbAp46 has been shown to be a core component of the mSin3 histone deacetylase （HDAC） complex and NuRD （ a multi-subunit complex containing chromosome-remodeling activity）. 2 RbAp46 is also known as the histone acetyltransferase （HAT） type B subunit

The role of RAS effectors in BCR/ABL induced chronic myelogenous leukemia

BCR/ABL is the causative agent of chronic myelogenous leukemia(CML).Through structure/function analysis,several protein motifs have been determined to be important for the development of leukemogenesis.Tyrosine177 of BCR is a Grb2 binding site required for BCR/ABL-induced CML in mice.In the current study,we use a mouse bone marrow transduction/transplantation system to demonstrate that addition of oncogenic NRAS(NRASG12D)to a vector containing a BCR/ABL^(Y177F)mutant“rescues”the CML phenotype rapidly and efficiently.To further narrow down the pathways downstream of RAS that are responsible for this rescue effect,we utilize well-characterized RAS effector loop mutants and determine that the RAL pathway is important for rapid induction of CML.Inhibition of this pathway by a dominant negative RAL is capable of delaying disease progression.Results from the present study support the notion of RAL inhibition as a potential therapy for BCR/ABL-induced CML.

Preliminary Research on the p53 Gene Rearrangements in the Evolution of Chronic Myelogenous Leukemia to Blast Crisis

DNA from 36 patients with chronic myelogenous leukemia (CML) at various clinical stages and 6 cases of acute leukemia was investigated for alterations of the p53 gene by Southern blot analysis.Rearrangements of the p53 gene were seen in 3 of 12 (25.00%) cases of blast crisis and accelerated phase (AP) of CML and in only one of 18 chronic phrase (CP),just as has been reported previously. Meanwhile,by restriction fragment length polymorphism (RFLP) analysis the Bgl II site polymorphism in the p53 gene was also found. The frequency in Chinese people detected here was 0.392,which was strikingly higher than that in some other countries(P<0. 001).These results suggested that the alterations of the p53 gene, for example,p53 rearrangements,were probably responsible for the progression of BC in some CML patients, and that the frequency of Bgl II polymorphism in the p53 gene might be related to the population distribution.

GENE THERAPY USING RETROVIRAL VECTOR OF bcr-abl SPECIFIC MULTI-UNIT RIBOZYMES COULD INHIBIT CML CELL GROWTH AND INDUCE APOPTOSIS

Objective: To investigate the in vitro cleavage ability and effects on apoptosis and cell growth of the bcr-abl fusion gene specific multi-unit ribozymes. Methods: Three fusion point specific ribozymes were designed and the multi-unit ribozymes?in vitro transcription vector and retroviral vector were constructed. The in vitro cleavage ability was tested. The retroviral vector was transfected into K562 cell and the effects on proliferation, apoptosis, cell cycle and cell structure were observed. Results: Multi-unit ribozymes had in vitro cleavage efficiency of 70.8%, which was more efficient than single-unit and double-unit ribozymes. Transfection of the retroviral vector of the ribozyme into K562 cells, induced inhibition of cell growth and apoptosis. The incorporation rate of DNA in ribozymes transfected K562 cells was greatly decreased along with time passed, with an inhibition rate of more than 50% after 96 h of transfection. Under FCM, 18.4% of the cells underwent apoptosis 72 h after transfection and more cells were blocked in G phase, with the ratio in S phase greatly decreased (41.9%). Under electron microscope, compaction of nuclear chromatin and apoptosis bodies were observed. Conclusion: Multi-unit ribozymes specific to bcr-abl fusion gene can be used to treat CML and to purge bone marrow for self-grafting.

ABNORMAL PROTEIN TYROSINE KINASES ASSOCIATED WITH HUMAN HAEMATOLOGICAL MALIGNANCIES

Objective: To survey the role of protein tyrosine kinases (PTKs) in the pathogenesis of several hematopoietic malignancies. Methods: By reviewing the published laboratory and clinical studies on PTK-related oncoproteins and their causative role in some leukemias and lymphomas. Results: Protein tyrosine kinases are key participants in signal transduction pathways that regulate cellular growth, activation and differentiations. Aberrant PTK activity resulting from gene mutation (often accompanying chromosome translocation) plays an etiologic role in several clonal hematopoietic malignancies. For example, the PTK product of the BCR-ABL fusion gene resulting from the t (9; 22) translocation exhibits several fold higher tyrosine kinase activity than the product of the ABL gene. Evidence suggests that the BCR-ABL oncoprotein alone is sufficient to case chronic myelogenous leukemia (CML) and other Ph positive acute leukemia. PTK over-activity resulting from chromosomal translocations creating TEL-ABL, TEL-JAK2 and TEL-PDGFRβ fusion proteins plays an important role in the pathogenesis of other types of leukemia. Another example occurs in anaplastic large cell lymphoma (ALCL). Experimental and clinical evidences indicate that translocations involving ALK gene on chromosome 2p23, most commonly resulting in an NPM-ALK fusion oncogene, result in constitutive activation of ALK and cause ALCL. This group of lymphomas is now named ALK positive lymphoma or ALKoma. Conclusion: Genetic lesions creating aberrant fusion proteins that result in excessive PTK activity are increasingly being recognized as central to the pathogenesis of hemotopoietic malignancies. These chimeric PTK molecules represent attractive disease-specific targets against which new classes therapeutic agents are being developed.

EFFECTS OF IFN-a COMBINED WITH IL-6 ON GROWTH AND EXPRESSION OF THE GENES RELATED TO CELL-GROWTH AND APOPTOSIS OF BONE MARROW CELLS FROM PATIENTS WITH CML

Objective:To investigate the effects of interferon-a (IFN-a) and IFN-a combined with interleukin-6 (IL-6) on growth and expression of bcr-abl, bcl-2 and c--myc genes in the mononuclear cells (MNCs) from bone marrow (BM) of patients with chronic myelogenous leukemia (CML). Methods: MNCs were collected from BM of the patients with CML in chronic phase by centrifugation in lymphocyte separation medium and cultured in liquid with IFN-a (200U/ml) or IFN-a (200U/ml) plus IL-6 (100 ng/ml). The growing cells were counted every day. The expression levels of b-actin, bcr-abl, bcl-2 and c-myc genes in the MNCs incubated for 24 h were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and relatively quantitative analysis of the amplified fragments by optical density scanning for the bands on gel. Results: The cell growth was markedly suppressed by IFN-a but the degree of cell-growth inhibition was slightly decreased by IL-6 on the basis of IFN-a effect. The expression of bcr-abl chimeric gene was intensely inhibited by IFN-a or IFN-a plus IL-6. The expression of bcl-2 gene was suppressed by either IFN-a or IFN-a plus IL-6, whereas that of c-myc gene was also inhibited by IFN-a but strongly elevated by IL-6 on the basis of IFN-a action. Conclusions: Both IFN-a and IFN-a plus IL-6 can inhibit the expression of anti-apoptosis gene such as bcr-abl and bcl-2 and regulate the expression of the cs.hn.cn gene related to cell proliferation and differentiation such as c-myc. Either IFN-a or IFN-a combined with IL-6 will serve as a trustful strategy of clinical treatment for CML.

Is dose modification or discontinuation of nilotinib necessary in nilotinib-induced hyperbilirubinemia?

Nilotinib is a specific breakpoint cluster region-Abelson leukemia virus-tyrosine kinase inhibitor that is used as an effective first-or second-line treatment in imatinib-resistant chronic myelogenous leukemia(CML)patients.Hepatotoxicity due to nilotinib is a commonly reported side effect;however,abnormal liver function test(LFT)results have been reported in asymptomatic cases.When alanine aminotransferase(ALT)and aspartate aminotransferase(AST)levels are more than five-fold the upper limit of the normal(ULN)or when the serum total bilirubin level is more than three-fold the ULN,dose modification or discontinuation of nilotinib is recommended,resulting in decreased levels of hematological indicators in certain patients with CML.Nilotinib-induced hyperbilirubinemia typically manifests as indirect bilirubinemia without elevated ALT or AST levels.Such abnormal liver functioning is thus not attributed to the presence of a true histologic lesion of the liver.The underlying mechanism may be related to the inhibition of uridine diphosphate glucuronosyltransferase activity.Therefore,nilotinib dose adjustment is not recommended for this type of hyperbilirubinemia,and in the absence of elevated liver enzyme levels or presence of abnormal LFT findings,physicians should consider maintaining nilotinib dose intensity without modifications.

Proteomic analysis of nuclear matrix proteins during arsenic trioxide induced apoptosis in leukemia K562 cells

Background Arsenic trioxide (As2O3) has been identified as a very potent antiacute leukemic agent However its role in apoptosis needs to be elucidated As2O3 interferes with the proliferation and survival of tumor cells via a variety of mechanisms Drugtarget interactions at the level of nuclear matrix (NM) may be critical events in the induction of cell death by As2O3 This study dealt with As2O3-target interactions at the level of NM in chronic myelogenous leukemia cell line K562 by proteomics Methods K562 cells were cultured in MEM and treated with different concentrations of As2O3 The nuclear matrix proteins were analyzed by highresolution twodimensional gel electrophoresis and computerassisted image analysis Results As2O3 significantly inhibited the growth of chronic myelogenous leukemia cell line K562 at low concentrations While more than 200 protein spots were shared among the nuclear matrices, about 18 distinct spots in the nuclear matrices were found characteristic for As2O3 treated cells Conclusions: As2O3 induces apoptosis in K562 cells in a dose and timedependent manner Our results demonstrated that for the detection of the onset of apoptosis, the alteration in the composition of nuclear matrix proteins was a more sensitive indicator than nucleosomal DNA fragmentation test These results indicated that As2O3 might be clinically useful in the treatment of chronic myelogenous leukemia. The changes of nuclear matrix proteins in the treated cells can be used as a useful indicator for this treatment

Expression patterns of WT-1 and Bcr-Abl measured by TaqMan quantitative real-time RT-PCR during follow-up of leukemia patients with the Ph chromosome

Background This study was designed to quantitatively measure WT-1 expression levels in patients with chronic myelogenous leukemia (CML) and acute lymphoblastic leukemia (ALL) during follow-up and to clarify the value of WT-1 as a molecular marker in minimal residual disease monitoring.Methods The TaqMan quantitative real-time RT-PCR method was established by using cloned WT-1 cDNA or synthesized oligonucleotides resembling WT-1 cDNA fragments in limit dilution as template until a stable and reliable standard curve was obtained. In a 25-month follow-up, the transcriptional levels of WT-1, Bcr-Abl, and Abl gene, were quantitatively measured in bone marrow cells from 25 CML or acute lymphoblastic leukemia (ALL) patients with the Ph chromosome. In addition, the expression of these genes in 40 samples of normal peripheral blood was also examined using the same method. The ratios of WT-1/Abl and Bcr-Abl/Abl were both plotted, and the two expression patterns were compared as well as their clinical significance.Results The levels of WT-1 expression in normal peripheral blood were detectable. In CML and Ph positive ALL patients, WT-1 expression levels changed in parallel with the Bcr-Abl expression pattern as the disease progressed or responded to effective treatment.Conclusion WT-1 expression provides a novel molecular marker in addition to Bcr-Abl for monitoring minimal residual disease (MRD) and targeting therapy in Ph chromosome-positive leukemia patients.

HDAC I/IIb selective inhibitor Purinostat Mesylate combined with GLS1 inhibition effectively eliminates CML stem cells

Purinostat Mesylate(PM)is a novel highly selective and active HDAC I/IIb inhibitor,and the injectable formulation of PM(PMF)based on the compound prescription containing cyclodextrin completely can overcome PM’s poor solubility and improves its stability and pharmacokinetic properties.Here,we showed that PM effectively repressed the survival of Ph+leukemia cells and CD34+leukemia cells from CML patients in vitro.In vivo studies demonstrated that PMF significantly prevented BCR-ABL(T315I)induced CML progression by restraining leukemia stem cells(LSCs),which are insensitive to chemotherapy and responsible for CML relapse.Mechanism studies revealed that targeting HDAC I/IIb repressed several important factors for LSCs survival including c-Myc,β-Catenin,E2f,Ezh2,Alox5,and mTOR,as well as interrupted some critical biologic processes.Additionally,PMF increased glutamate metabolism in LSCs by increasing GLS1.The combination of PMF and glutaminase inhibitor BPTES synergistically eradicated LSCs by altering multiple key proteins and signaling pathways which are critical for LSC survival and self-renewal.Overall,our findings represent a new therapeutic strategy for eliminating LSCs by targeting HDAC I/IIb and glutaminolysis,which potentially provides a guidance for PMF clinical trials in the future for TKI resistance CML patients.

Allo-hematopoietic stem cell transplantation is a potential treatment for a patient with a combined disorder of hereditary spherocytosis

Both human hereditary spherocytosis （HS） and chronic myelogenous leukemia （CML） are life threatening. Herein we have reported the case of a woman with a combined disorder of HS and CML who underwent the matched sibling allogeneic stem cell transplantation. The complete donor erythroid cells were obtained. The red blood cell counts significantly improved throughout life comparing with pre-hematopoietic stem cell transplantation （HSCT）. Reticulocyte counts normalized, and BCR-ABL was cleared away. The total bilirubin level was also corrected in this recipient. Our case is a rare example with a combined disorder of HS and CML following allogeneic stem cell transplantation. HS was not a contraindication for patient in the matched sibling transplant setting.