Novel PIKfyve/Tubulin Dual-target Inhibitor as a Promising Therapeutic Strategy for B-cell Acute Lymphoblastic Leukemia

Objective:In B-cell acute lymphoblastic leukemia(B-ALL),current intensive chemotherapies for adult patients fail to achieve durable responses in more than 50%of cases,underscoring the urgent need for new therapeutic regimens for this patient population.The present study aimed to determine whether HZX-02-059,a novel dual-target inhibitor targeting both phosphatidylinositol-3-phosphate 5-kinase(PIKfyve)and tubulin,is lethal to B-ALL cells and is a potential therapeutic for B-ALL patients.Methods:Cell proliferation,vacuolization,apoptosis,cell cycle,and in-vivo tumor growth were evaluated.In addition,Genome-wide RNA-sequencing studies were conducted to elucidate the mechanisms of action underlying the anti-leukemia activity of HZX-02-059 in B-ALL.Results:HZX-02-059 was found to inhibit cell proliferation,induce vacuolization,promote apoptosis,block the cell cycle,and reduce in-vivo tumor growth.Downregulation of the p53 pathway and suppression of the phosphoinositide 3-kinase(PI3K)/AKT pathway and the downstream transcription factors c-Myc and NF-κB were responsible for these observations.Conclusion:Overall,these findings suggest that HZX-02-059 is a promising agent for the treatment of B-ALL patients resistant to conventional therapies.

Damage Mechanism of CK2 and IKAROS in Philadelphia Like Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is characterized by immature and poorly differentiated B lymphocytes in large numbers in the blood. B cells are distinct from the cell types involved in their development (common lymphoid progenitor cells, pro-B cells, pre-B cells, and mature cells). The process of B cell maturation depends on precise communication within the cell: signals activate specific genes that are essential for proper development. Errors in this intricate signaling network can lead to issues with B cell function and contribute to disease. B-lineage acute lymphoid leukemias, malignancies of precursor-stage B lymphoid cells inhibit lymphoid differentiation, leading to abnormal cell proliferation and survival. The process of developing leukemia (leukemogenesis) can be triggered by an overproduction of both hematopoietic stem cells (the cells that form all blood cells) and the immature versions of white blood cells called lymphoblasts. Acute lymphoblastic leukemia (ALL) with the presence of the Philadelphia chromosome (ALL Ph) is classified as a high-risk manifestation of the disease, this chromosome is the product of the reciprocal translocation, whose product is a BCR-ABL fusion protein. It is a highly active tyrosine kinase that can transform hematopoietic cells into cytokine-independent. Hyperphosphorylation cascades inhibit the differentiating function of IKZF1 as a tumor suppressor gene which leads to an abnormal proliferation of B cells due to the presence of the Philadelphia chromosome;it inhibits the differentiating process, leukemogenesis involving immature B cells in the bloodstream can result from the uncontrolled growth and division of hematopoietic stem cells and immature lymphoblasts (the precursors to B cells).

The Role of Mitochondrial VDAC2 in the Survival and Proliferation of T-Cell Acute Lymphoblastic Leukemia Cells

Background: T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy with aberrant T-cell developmental arrest. Individuals with relapsed T-ALL have limited therapeutic alternatives and poor prognosis. The mitochondrial function is critical for the T-cell viability. The voltage-dependent anion channel 2 (VDAC2) in the mitochondrial outer membrane, interacts with pro-apoptotic BCL-2 proteins and mediates the apoptosis of several cancer cell lines. Objective: The aim of the current study is to explore the role of VDAC2 in T-ALL cell survival and proliferation. Methods: Publicly available datasets of RNA-seq results were analyzed for expression of VDAC isoforms and T-ALL cell lines were treated with a VDAC2 small molecular inhibitor erastin. A VDAC2 RNA interference (siRNA) was delivered to T-ALL cell lines using a retroviral vector. Functional assays were performed to investigate the VDAC2 siRNA impacts on cell proliferation, apoptosis and survival of T-ALL cells. Results: Our analysis found a high expression of VDAC2 mRNA in various T-ALL cell lines. Public datasets of T-ALL RNA-seq also showed that VDAC2 is highly expressed in T-ALL (116.2 ± 36.7), compared to control groups. Only two T-ALL cell lines showed sensitivity to erastin (20 μM) after 48 hours of incubation, including Jurkat (IC50 = 3.943 μM) and Molt4 (IC50 = 3.286 μM), while another two T-ALL cells (CUTLL1 and RPMI 8402) had unstable IC50. However, five T-ALL cell lines (LOUCY, CCRF-CEM, P12-ICHI, HPB-ALL, and PEER cells) showed resistance to erastin. On the contrary, all T-ALL cell lines genetically inhibited with VDAC2 siRNA led to more than 80% decrease in VDAC2 mRNA levels, and a Conclusion: VDAC2 is highly expressed in T-ALL cells. The inhibition of VDAC2 significantly decreased cell viability, increased apoptosis, reduced cell proliferation and caused cell cycle sub-G1 arrest of T-ALL cells.

Comparison of the Effects of L-asparaginase and Pegaspargase in the Treatment of Adult Acute Lymphoblastic Leukemia

Objective:To compare the effect of L-asparaginase and pegaspargase in the treatment of adult acute lymphoblastic leukemia.Methods:In this study,96 patients who received treatment at the Shaanxi Provincial People’s Hospital from April 2019 to April 2021 were selected.The control group received L-asparaginase treatment,and the observation group received pegaspargase treatment.The curative effect and adverse reaction rate were compared between the two groups.Results:Comparing the experimental statistical results of the observation and the control groups,it can be concluded that the effect of the former group is better than that of the latter group in terms of clinical curative effect and statistics of adverse reactions.Conclusion:In the treatment of adult acute lymphoblastic leukemia,the application of pegaspargase therapy has a significantly better clinical effect and is worthy of further promotion.

Study of Minimal Residual Disease in Adults with B-Lineage Acute Lymphoblastic Leukemia by Flowcytometry

Background: After achieving morphological remission, existence of few number of leukemic cells in the patient’s blood represents the minimal residual disease (MRD) and its monitoring helps in evaluating early treatment response and future relapse. Patients and methods: Eighty seven newly diagnosed (B-ALL) cases were enrolled in the present study in the time period from October 2013 to October 2016. A panel of 4 monoclonal antibodies (CD10FITC, CD19PE, CD34PercP and CD45APC) were defined at diagnosis and after morphological remission for tracing of minimal residual disease (MRD). Results: Eighty seven newly diagnosed B-ALL cases were included in the present study of which 73 (84%) showed positive expression to CD45 in combination with (CD10, CD19 and CD34) at diagnosis, which allow us to use this combination for further assessment of MRD after morphological remission. In our study 65% of patients had negative MRD ( Conclusion: MRD detection by flow cytometry using the combination of CD45 with CD10, CD19 & CD34 is an easy and reliable method. Patients with positive MRD are at higher risk of relapse and have inferior overall survival rates compared to those with MRD-ve. Future studies focusing on treatment intensification for the group of patients with +ve MRD aiming to improve the treatment outcome are warranted.

Myelodysplastic syndrome transformed into B-lineage acute lymphoblastic leukemia: A case report

BACKGROUND Myelodysplastic syndromes(MDSs)are a group of hematological diseases caused by expansion of an abnormal clone of hematopoietic stem cells.Primary MDS is a potentially premalignant clonal disorder that may progress to overt acute leukemia in 25%-50%of cases.However,most of these cases evolve into acute myeloid leukemia and rarely progress to acute lymphoblastic leukemia(ALL).Thus,transformation of MDS into B-cell ALL is rare.CASE SUMMARY A 58-year-old man was admitted to the hospital for reduced blood cell counts.Based on all the test results and the World Health Organization diagnosis and classification,the patient was finally diagnosed with ring-shaped sideroblastic MDS with refractory hemocytopenia due to multilineage dysplasia.We used red blood cell transfusions and other symptomatic support treatments.After 4 years,the patient felt dizziness,fatigue,and night sweats.We improved bone marrow and peripheral blood and other related auxiliary examinations.He was eventually diagnosed with B-lineage acute lymphocytic leukemia(MDS transformation).CONCLUSION The number of peripheral blood cells,type of MDS,proportion of primitive cells in bone marrow,and number and quality of karyotypes are all closely related to the conversion of MDS to ALL.

Macrophage Activation Syndrome in a Context of Pre-B Type Lymphoblastic Acute Leucemia: A Case Report

Macrophage activation syndrome (MAS) is linked to inappropriate stimulation of macrophage cells in the bone marrow and lymphoid system, resulting in abnormal phagocytosis of figurative blood elements and the release of pro-inflammatory cytokines. It is a rare and serious hyper-inflammatory condition of diagnostic and therapeutic emergency. MAS is characterized by non-specific clinical and laboratory signs associated with images of hemophagocytosis. MAS is either “primary” (familial or pediatric forms), or “secondary/reactive” to infection, neoplasia, or autoimmune disease. Hemopathies dominate MAS secondary to neoplasia. B-type acute lymphoblastic leukemia (ALL) is a hematological malignancy characterized by the proliferation and accumulation of B lymphoid progenitors, blocked at an early stage of differentiation, leading to suppression of polyclonal hematopoiesis and subsequent development of signs associated with bone marrow failure. In this context, we report the observation of a macrophage activation syndrome (MAS) associated with ALL, diagnosed at Hôpital Principal de Dakar/Senegal, in a 69-year-old patient with a well-controlled type 2 diabetes under oral antidiabetic therapy (OAD) and good general condition.

Resveratrol Induces Apoptosis and Autophagy in T-cell Acute Lymphoblastic Leukemia Cells by Inhibiting Akt/mTOR and Activating p38-MAPK

Objective To explore the effects of resveratrol-induced apoptosis and autophagy in T-cell acute lymphoblastic leukemia （T-ALL） cells and potential molecular mechanisms. Methods The anti-proliferation effect of resveratrol-induced, apoptosis and autophagy on T-ALL cells were detected by using MTI- test, immunofluorescence, electronic microscope, and flow cytometry, respectively. Western blotting was performed for detecting changes of apoptosis-associated proteins, cell cycle regulatory proteins and state of activation of Akt, mTOR, p70S6K, 4E-BP1, and p38-MAPK. Results Resveratrol inhibited the proliferation and dose and time-dependent manner. It also induced cyclin-dependent kinase （CDK） inhibitors p21 and induced apoptosis and autophagy in T-ALL cells in a cell cycle arrest at G0/G1 phase via up regulating p27 and down regulating cyclin A and cyclin D1. Western blotting revealed that resveratrol significantly decreased the expression of antiapoptotic proteins （Mcl-1 and Bcl-2） and increased the expression of proapoptotic proteins （Bax, Bim, and Bad）, and induced cleaved-caspase-3 in a time-dependent manner. Significant increase in ratio of LC3-11/LC3-1 and Beclin 1 was also detected. Furthermore, resveratrol induced significant dephosphorylation of Akt, mTOR, p70S6K, and 4E-BP1, but enhanced specific phosphorylation of p38-MAPK which could be blocked by SB203580. When autophagy was suppressed by 3-MA, apoptosis in T-ALL cells induced by resveratrol was enhanced. Conclusion Our findings have suggested that resveratrol induces cell cycle arrest, apoptosis, and autophagy in T-ALL cells through inhibiting Akt/mTOR/p7OS6K/4E-BP1 and activating p38-MAPK signaling pathways. Autophagy might play a role as a self-defense mechanism in T-ALL cells treated by resveratrol. Therefore, the reasonable inhibition of autophagy in T-ALL cells may serve as a promising strategy for resveratrol induced apoptosis and can be used as adjuvant chemotherapy for T-ALL.

Donor-Derived CD19-Targeted T Cell Infusion Eliminates B Cell Acute Lymphoblastic Leukemia Minimal Residual Disease with No Response to Donor Lymphocytes after Allogeneic Hematopoietic Stem Cell Transplantation

Leukemia relapse is still the leading cause of treatment failure after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for B cell acute lymphoblastic leukemia (B-ALL). Relapsed patients with BALL after allo-HSCT have a very short median survival. Minimal residual disease (MRD) is predictive of forthcoming hematological relapse after hematopoietic stem cell transplantation (HSCT);furthermore, eliminating MRD effectively prevents relapse. Donor lymphoblastic infusion (DLI) is the main established approach to treat B-ALL with MRD after allo-HSCT. However, about one-third of patients with MRD are non-responsive to DLI and their prognosis worsens. Although donor-derived cluster of differentiation (CD)19-directed chimeric antigen receptor-modified (CAR) T cells (CART19s) can potentially cure leukemia, the efficiency and safety of infusions with these cells have not yet been investigated in patients with MRD after HSCT. Between September 2014 and February 2018, six patients each received one or more infusions of CART19s from HSCT donors. Five (83.33%) achieved MRD-negative remission, and one case was not responsive to the administration of CAR T cells. Three of the six patients are currently alive without leukemia. No patient developed acute graft-versus-host disease (aGVHD), and no patient died of cytokine release syndrome. Donor-derived CAR T cell infusions seem to be an effective and safe intervention for patients with MRD in B-ALL after allo-HSCT and for those who were not responsive to DLI.

Decitabine for Relapsed Acute Lymphoblastic Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation

Relapse after allogeneic hematopoietic stem cell transplantation（allo-HSCT） remains a main question on treatment failure. Current strategies for management that usually include salvage chemotherapy, donor lymphocytic infusion and second transplantation. Our study assessed the efficacy of decitabine（DAC） for treating patients with acute lymphoblastic leukemia（ALL） who relapsed after allogeneic hematopoietic stem cell transplantation（allo-HSCT）. We retrospectively analyzed the outcomes of 12 patients with relapsed ALL after allo-HSCT who received DAC therapy. Nine patients received DAC combined with chemotherapy and donor stem cell infusion, and 3 patients received single-agent DAC. Ten of the 12 patients achieved complete remission（CR）, 1 achieved a partial remission（PR）, and 1 had no response（NR） after treatment at the latest follow-up（LFU）, the median survival was 11.2 months（range, 3.8–34, 7 months）. The 1-and 2-year overall survival（OS） rates were 50%（6/12） and 25%（3/12）, respectively. Five patients were still alive; 4 had maintained CR and 1 was alive with disease. Patients with Philadelphia chromosome-positive ALL had higher survival rate than patients with Philadelphia chromosome-negative ALL（57.1% vs. 20%）. No aggravated flares of graft-versus-host disease（GVHD） were observed during DAC treatment. Therefore, DAC may be a promising therapeutic agent for ALL recurrence after allo-HSCT.

Philadelphia chromosome-positive leukemia stem cells in acute lymphoblastic leukemia and tyrosine kinase inhibitor therapy

Leukemia stem cells(LSCs),which constitute a minority of the tumor bulk,are functionally defined on the basis of their ability to transfer leukemia into an immunodeficient recipient animal.The presence of LSCs has been demonstrated in acute lymphoblastic leukemia(ALL),of which ALL with Philadelphia chromosome-positive(Ph+).The use of imatinib,a tyrosine kinase inhibitor(TKI),as part of front-line treatment and in combination with cytotoxic agents,has greatly improved the proportions of complete response and molecular remission and the overall outcome in adults with newly diagnosed Ph+ ALL.New challenges have emerged with respect to induction of resistance to imatinib via Abelson tyrosine kinase mutations.An important recent addition to the arsenal against Ph+ leukemias in general was the development of novel TKIs,such as nilotinib and dasatinib.However,in vitro experiments have suggested that TKIs have an antiproliferative but not an antiapoptotic or cytotoxic effect on the most primitive ALL stem cells.None of the TKIs in clinical use target the LSC.Second generation TKI dasatinib has been shown to have a more profound effect on the stem cell compartment but the drug was still unable to kill the most primitive LSCs.Allogeneic stem cell transplantation(SCT) remains the only curative treatment available for these patients.Several mechanisms were proposed to explain the resistance of LSCs to TKIs in addition to mutations.Hence,TKIs may be used as a bridge to SCT rather than monotherapy or combination with standard chemotherapy.Better understanding the biology of Ph+ ALL will open new avenues for effective management.In this review,we highlight recent findings relating to the question of LSCs in Ph+ ALL.

Rapamycin Sensitizes Glucocorticoid Resistant Acute Lymphoblastic Leukemia CEM-C1 Cells to Dexamethasone Induced Apoptosis through both mTOR Suppression and Up-Regulation and Activation of Glucocorticoid Receptor

Objective To explore the role of glucocorticoid （GC） receptor （GR） in rapamycin＇s reversion of GC resistance in humanGC-resistant T-acute lymphoblastic leukemia （ALL） CEM-C1 cells. Methods CEM-C1 cells were cultured in vitro and treated with rapamycin at different concentrations with or without 1 μmol/L dexamethasone （Dex）. 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） test was performed to assess cell proliferation. The cell cycle and cell apoptosis were analyzed by flow cytometry. The expression of GRα mRNA was determined by real-time quantitative RT-PCR. The expression of GR, p-70S6K, Mcl-1, and Bim proteins was detected by Western blot. Results When incubated with rapamycin at different concentrations, CEM-C1 cells showed significant growth inhibition in a time- and concentration-dependent manner. The growth inhibition was synergistically increased when CEM-C1 cells were treated with rapamycin plus 1 μmol/L Dex. CEM-C1 cells treated with rapamycin alone showed no apparent apoptosis, and were arrested at G0/G1 phase. After the treatment with Dex plus rapamycin, CEM-C1 cells demonstrated apparent apoptosis and increased the cell cycle arrested at G0/G1 phase. Rapamycin combined with Dex up-regulated GRα, phosphorylated GR（p-GR）, and pro-apoptotic protein Bim-EL in CEM-C1 cells, but inhibited the expression of p-p70S6K, a downstream target protein ofmTOR （mammalian target of rapamycin）. Conclusion After the treatment with rapamycin plus Dex, Dex resistant CEM-C1 cells induce growth inhibition and apoptosis. The underlying mechanism may involve inhibition of the mTOR signaling pathway and also be associated with up-regulation of GR expression and activation of GC-GR signaling pathway.

Individualized leukemia cell-population profiles in common B-cell acute lymphoblastic leukemia patients

Immunophenotype is critical for diagnosing common B-cell acute lymphoblastic leukemia (common ALL) and detecting minimal residual disease. We developed a protocol to explore the immunophenotypic profiles of common ALL based on the expression levels of the antigens associated with B lymphoid development, including IL-7Rα (CD127), cytoplasmic CD79a (cCD79a), CD19, VpreB (CD179a), and sIgM, which are successive and essential for progression of B cells along their developmental pathway. Analysis of the immunophenotypes of 48 common ALL cases showed that the immunophenotypic patterns were highly heterogeneous, with the leukemic cell population differing from case to case. Through the comprehensive analysis of immunophenotypic patterns, the profiles of patient-specific composite leukemia cell populations could provide detailed information helpful for the diagnosis, therapeutic monitoring, and individualized therapies for common ALL.

DNA repair gene XRCC1 polymorphisms and susceptibility to childhood acute lymphoblastic leukemia: a meta-analysis

Objective： To estimate the relationship between genetic polymorphisms of X-ray repair cross- complementing group 1 （XRCC1） and the susceptibility to childhood acute lymphoblastic leukemia （ALL）. Methods： Relevant case-control studies were enrolled in the meta-analysis. We applied Rev Man 4.2 software to pool raw data and test studies＇ heterogeneity and to calculate the incorporated odds ratio （OR） and 95% confidence interval （95% CI）. Results： Our data showed that the OR for the Gln allele of the Arg399Gln polymorphism, compared with the Arg allele, was 1.35 （95% CI, 1.16-1.57; P〈0.0001） for childhood ALL patients. Similarly, the homozygous genotype Gln/Gln and heterozygous genotype Arg/Gln both significantly increased the risk of childhood ALL compared with the wild genotype Arg/Arg （OR =1.58; 95% CI, 1.13-2.21; P=0.008; OR =1.51; 95% CI, 1.21-1.87; P=0.0002）. The dominant model of Arg399Gln was associated with childhood ALL risk （OR =1.54; 95% CI, 1.25-1.89; P〈0.0001）. The ethnic subgroup analysis demonstrated that the Gln allele in all five ethnic groups was prone to be a risk factor for childhood ALL just with different degrees of correlation while Arg194Trp SNP showed a protective or risk factor or irrelevant thing in different races. Conclusions： XRCC1 399 polymorphism may increase the risk of childhood ALL. Different ethnic groups with some gene polymorphism have different disease risks.

Establishment of Reproducible Xenotransplantation Model of T Cell Acute Lymphoblastic Leukemia in NOD/SCID Mice

T cell acute lymphoblastic leukemia(T-ALL) is an aggressive leukemia.However the poor prognosis and low morbidity restrict further analysis of the disease.Therefore there is an increasing demand to develop animal models for identifying novel therapeutic approaches.In this study,we inoculated the anti-mouse CD122 monoclonal antibody conditioned NOD/SCID mice with the leukemia cells from 9 T-ALL patients and 1 cell line via the tail vein.Four of the 9 patients and the cell line were successfully engrafted.Flow cytometry detected high percentage of human CD45 + cells in recipient mice.Immunohistochemistry showed infiltration of human CD45 + cells in different organs.Serial transplantation was also achieved.In vivo drug treatment showed that dexamethasone could extend survival,which was consistent with clinical observation.These results demonstrated that we successfully established 5 xenotransplantation models of T-ALL in anti-mCD122 mAb conditioned NOD/SCID mice,which recapitulated the characteristics of original disease.

ATP binding cassette C1 (ABCC1/MRP1)-mediated drug efflux contributes to disease progression in T-lineage acute lymphoblastic leukemia

Purpose: In acute lymphoblastic leukemia (ALL), multidrug resistance is often mediated by AT- Pase Binding Cassette (ABC) proteins, which principally involve ABCC1 (multidrug resistance protein 1, MRP1) and ABCB1 (multidrug resistance 1, MDR1). However, direct comparisons between the differential effects of ABCC1 and ABCB1 have been difficult, since identical cell lines with differential expression of these transporters have not been developed. Experimental Design: In this study, we developed and compared the biological profiles of Jurkat cell lines that selectively over-expressed ABCC1 and ABCB1. Vincristine (VCR) plays an important role in the treatment of T-lineage ALL (T-ALL), and is often the first drug given to newly-diagnosed patients. Because of its importance in treatment, we provide descalating, sub-lethal doses of VCR to Jurkat cells, and extended our observations to expression profiling of newly diagnosed patients with T-ALL. Results: We found that VCR-resistant cells over-expressed ABCC1 nearly 30-fold. The calcein AM assay confirmed that VCR-resistant cells actively extruded VCR, and that ABCC1-mediated drug resistance conferred a different spectrum of multidrug resistance than other T-ALL induction agents. siRNA experiments that blocked ABCC1 export confirmed that VCR resistance could be reversed in vitro. Analyses of T-lymphoblasts obtained from 100 newly diagnosed T-ALL patients treated on Children’s Oncology Group Phase III studies 9404 and AALL0434 that induction failure could be could be partially explained by the over-expression of ABCC1 and ABCB1. Conclusions: Taken together, these results suggest that over-expression of ABC transporters plays a contributing role in mediating treatment failure in T-ALL, and underscore the need to employ alternate treatment approaches in patients for whom induction failed or for those with relapsed disease.

Pneumomediastinum after acute lymphoblastic leukemia and chemotherapy?

Pneumomediastinum,pneumorachis and subcutaneous emphysema are frequently benign and most commonly result from air escaping from the upper respiratory tract,intrathoracic airways,or gastrointestinal tract.Gas can also be generated by certain infections or reach the mediastinal space from outside air after trauma or surgery.In the article presented by Showkat et al a 14-year-old male patient with acute lymphoblastic leukemia(ALL) under chemotherapy developed pneumomediastinum,pneumorachis and subcutaneous emphysema.In the author's opinion,these complications were caused by ALL or chemotherapy that progressed to severe respiratory failure until the patient finally died in the intensive care unit.I would like to underline some important points,which have been raised following a paper published in the October issue of World Journal of Clinical Cases.

Unusual presentation of Erdheim-Chester disease in a child with acute lymphoblastic leukemia

Erdheim-Chester disease(ECD) is an uncommon, nonfamilial, non-Langerhans cell histiocytosis, which involves skeletal system and soft tissue usually in middle aged and elderly patients. The characteristic radiologic features include bilateral, symmetric cortical osteosclerosis of the diaphyseal and metaphyseal parts of the long bones, or bilateral symmetrically abnormal intense 99 mTechnetium labelling of the metaphyseal-diaphyseal region of the long bones, and computed tomography scan findings of "coated aorta" or "hairy kidneys". ECD in childhood with osteolytic lesion is extremely rare. We describe an unusual case with an expansile lytic bone lesion at presentation in a case of acute lymphoblastic leukemia.

Arsenic Trioxide Induces Apoptosis of Glucocorticoid-Resistant Acute Lymphoblastic Leukemia CEM-C1 Cells

Objective： To explore the effects of arsenic trioxide （ATO） on the apoptosis of glucocorticoid （GC）-resistant T-acute lymphoblastic leukemia （ALL） CEM-C1 cells and its possible mechanisms. Methods： Different concentrations of ATO （0.25 μmol/L-5 μmol/L） were used to induce the apoptosis of CEM-C1 cells. The inhibition rate of cell proliferation and apoptosis were detected by MTT test, Annexin V-FITC/PI flow cytometry and optical microscopy, respectively. RT-PCR was applied to semi-quantitatively analyze the mRNA expression of pro-apoptotic proteins （Bad and PDCD4） and anti-apoptotic proteins （XIAP and MCL-1） induced by different concentrations of ATO at different time points. Results： ATO could inhibit proliferation and induce apoptosis of CEM-C1 cells at a concentration and time dependent manner. Low-dose ATO mildly inhibited the proliferation of CEM-C1 cells while higher concentrations （1 μmol/L and 5 μmol/L） had strong anti-tumor effect with the inhibiting rates of 40.07±7.98% and 88.67±2.88%, respectively. Annexin V-FITC/PI flow cytometry showed that the apoptotic rates of CEM-C1 ceils were significantly increased after 48 hours treatment of different concentrations of ATO. RT-PCR demonstrated up-regulated mRNA expression of pro-apoptotic protein Bad and PDCD4 but down-regulated mRNA expression of anti-apoptotic protein XIAP when CEM-C1 cells were treated with different concentrations of ATO at different time points. The MCL-1 mRNA expression was down-regulated only after the treatment of 5 μmol/L ATO. Conclusion： ATO can inhibit cell proliferation and induce cell apoptosis in GC-resistant CEM-C1 cells. The molecular mechanisms might involve the increased mRNA expression of pro-apoptotic protein Bad and PDCD-4, and rapid down-regulation of XIAP mRNA expression.

A facile,branched DNA assay to quantitatively measure glucocorticoid receptor auto-regulation in T-cell acute lymphoblastic leukemia

Glucocorticoid(GC) steroid hormones are used to treat acute lymphoblastic leukemia(ALL) because of their pro-apoptotic effects in hematopoietic cells.However,not all leukemia cells are sensitive to GC,and no assay to stratify patients is available.In the GC-sensitive T-cell ALL cell line CEM-C7,auto-up-regulation of RNA transcripts for the glucocorticoid receptor(GR) correlates with increased apoptotic response.This study aimed to determine if a facile assay of GR transcript levels might be promising for stratifying ALL patients into hormone-sensitive and hormone-resistant populations.The GR transcript profiles of various lymphoid cell lines and 4 bone marrow samples from patients with T-cell ALL were analyzed using both an optimized branched DNA(bDNA) assay and a real-time quantitative reverse transcription-polymerase chain reaction assay.There were significant correlations between both assay platforms when measuring total GR(exon 5/6) transcripts in various cell lines and patient samples,but not for a probe set that detects a specific,low abundance GR transcript(exon 1A3).Our results suggest that the bDNA platform is reproducible and precise when measuring total GR transcripts and,with further development,may ultimately offer a simple clinical assay to aid in the prediction of GC-sensitivity in ALL patients.