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.

ANALYSIS OF APOPTOSIS BY DNA END LABELING METHOD (TDT) IN LEUKEMIA CELL LINES HL-60 AND U937

Antitumor-drug-indnced apoptosis in leukemia cell lines HL-60 and U937 was quantitatively analyzed with TDT (terminal deoxynuleotidyl transferase-mediated nick-end labeling) approach, which allows to labal the ends of DNA broken strands in apoptotic cells by biotinlated dUTP which to avidin-FITC. In this way the apoptotic cells show nuorescent when the labeling cells were emitted by UV light microscope or laser-activated now cell sorting at r=480. In our study, HL-6o and U937 cell lines were cocultured respectively with cisdiaminodicaicroplatinum (CDDP), hydroxycamptothecinum (HCT) and vindesini sulfa (VCR) for 18 hours.By calculating percentages of apoptotic cells with TDT mothod, we were able to show that the two cell lines gave different sensitivity to the drugs. HL-60 showed high sensitivity to CDDP but U937 cells were more sensitive to other two drugs, HCT and VCR. Meanwhile we compared the results of obtained by DNA gel electrophoresis with that by TDT. We found that gel electrophoresis is not sensitive enough to reveal apoptosis since there was no ladder structure, a typical electrophoresis pattern for apoptosis, appeared until the apoptotic cells reached or over 13%. And we report in this paper as first time that three forms of apoptotic cells could be detected under fluorescent microscope, which we called as spot form and crescent form and assembling form in terms of distribution of light spots within cell nuclei. It seemed that the spot form was at an early stage of apoptosis and the crescent form rcprtscntcd a later stage of apoptosis.

INDUCTION OF APOPTOSIS OF HUMAN LEUKEMIA CELLS BY α-ANORDRIN

The apoptosis-inducing effect of a-anordrin (ANO)was investigated in this study. ANO 10-50 AM inhibited the growth of both human leukemia HL-60 and K562cells by 19-52%. Electron microscopy showed that ANO-treated cells exhibited the drastic changes including cell shrinkage, chromatin condensation, nuclear fragmentation, typical of apoptosis. Gel electrophoresis of DNA extracted farm botlt HL-60 and K562 cells treated with ANO revealed characteristic 'ladder' pattern.ANO 50 μM for 48 h caused approximately 50-70%apoptosis. Cycloheximide (CHX) and actinomycin D (Act D) did not prevent ANO-induced apoptosis in K562cells, however, apoptosis of HL-60 cells in the presence of ANO was partially blocked by these two agents.Moreover, it was found that tamoxifen synergically potcntiated and cstradiol partially antagonized ANOinduccd apoptosis in HL-60 cells. Results demonstrated that ANO could induce tumor cell apoptosis, which might contribute to its anticancer action.

OPTIMIZATIONS FOR 5-AMINOLEVULINIC ACID BASED PHOTODYNAMIC THERAPY IN PURGING LEUKEMIA CELL HL60

Objective To optimize experimental parameters for the photosensitization of 5-aminolevulinic acid (ALA) in promyelocytic leukemia cell HL60 and compare them with normal human peripheral blood mononuclear cell (PBMC). Methods ALA incubation time, wavelength applied to irradiate, concentration of ALA incubated, irradiation fluence may modulate the effect of 5-aminolevulinic acid based Photodynamic Therapy (ALA-PDT).The high-pressure mercury lamps of 400W served as light source, the interference filter of 410nm, 432nm, 545nm, 577nm were used to select the specific wavelength. Fluorescence microscope was used to detect the fluorescence intensity and location of protoporphyrin IX (PpIX) endogenously produced by ALA. MTT assay was used to measure the survival of cell. Flow cytometry with ANNEXIN V FITC kit (contains annexin V FITC, binding buffer and PI) was used to detect the mode of cell death. Results ① 1mmol/L ALA incubated 1×105/mL HL60 cell line for 4 hours, the maximum fluorescence of ALA induced PpIX was detected in cytomembrane. ② Irradiated with 410nm for 14.4J/cm2 can result in the minimum survivability of HL60 cell. ③ The main mode of HL60 cell death caused by ALA-PDT is necrosis. Conclusion ALA for 1mmol/L, 4 hours for dark incubation time, 410nm for irradiation wavelength, 14.4J/cm2 for irradiation fluence were the optimal parameters to selectively eliminate promyelocytic leukemia cell HL60 by ALA based PDT. The photosensitization of ALA based PDT caused the necrosis of HL60 cell, so it could be used for inactivation of certain leukemia cells.

NUCLEAR MATRIX PROTEIN IN LEUKEMIA CELLS

Objective: To compare the composition of nuclear matrix proteins (NMP) between leukemia cells and normal bone marrow cells. Methods: NMP was isolated by high-salt extraction and identified in acute and chronic myelogenous leukemia cells as well as in the blast phase of chronic leukemia. On SDS-PAGE, NMPs with molecular myelogenous ferment from what were seen in normal bone marrow cells were present in both acute and chronic myelogenous leukemia. Conclusion: Marked changes of NMP, not only in contents but also in compositions, exist in leukemic cells compared with normal bone marrow cells. NMP may serve as a target of chemotherapeutic drug against leukemia.

IN VIVO COMPARATIVE OBSERVATION ON THE INVASIVENESS OF VARIOUS ORGANS BY DIFFERENT LEUKEMIA CELLS

Using patho-morphological method and transplantation bio-assay, the in vivo invasiveness of leukemia cells is three transplantable mouse T cell leukemia models was comparatively studied. The results showed that the invasion to the liver was consistent, but that to other organs was obviously different. L615 and L7212 leukemia cells preferred to the bone marrow and spleen than to the peritoneum while L7811 leukemia cells were just the opposite. Transplantation bio-assay demonstrated that leukemia cells were present in the bone marrow of L615 mice as early as 6 hours after leukemic cell inoculation, but no leukemia cells was detected in bone marrow of L7811 mice 2 days after inoculation. In the terminal phase, L615 mice bone marrow became filled with leukemia cells, but L7811 mice bone marrow contained only a few leukemia cells. The difference of invasiveness of leukemia cells among organs is probably related to "homing" receptor. The same type of leukemia cells may possess multiple "homing" receptor.

ADVANCES IN THE STUDY ON LEUKEMIA STRAINS AND LEUKEMIA CELL LINES IN CHINA

The study and establishment of leukemia strains and leukemia cell lines have made great achievement in China.It has been extended from mice to rat model and related to explore human leukemia cell line and heterotransplantable tumor strains. The cellular types of leukemia strain have included Iymphocytic,tmyelocytic,ecythroleukmia and megakaryoblastic cell strain.

NF-κB promotes the stem-like properties of leukemia cells by activation of LIN28B

AIM To examine whether nuclear factor kappa B(NF-κB) activity regulates LIN28 B expression and their roles in leukemia stem cell(LSC)-like properties. METHODS We used pharmacological inhibitor and cell viability assays to examine the relation between NF-κB and LIN28 B. Western blot and q RT-PCR was employed to determine their protein and m RNA levels. Luciferase reporter was constructed and applied to explore the transcriptional regulation of LIN28 B. We manipulated LIN28 B level in acute myeloid leukemia(AML) cells and investigated LSC-like properties with colony forming and serial replating assays. RESULTS This study revealed the relationship between NF-κB and LIN28 B in AML cells through drug inhibition and overexpression experiments. Notably,inhibition of NF-κB by pharmacological inhibitors reduced LIN28 B expression and decreased cell proliferation. We demonstrated that NF-κB binds to the-819 to-811 region of LIN28 B promoter,and transcriptionally regulates LIN28 B expression. LIN28 B protein was significantly elevated in NFκB1 transfected cells compared to vector control. Importantly,ectopic expression of LIN28 B partially rescued the self-renewal capacity impaired by pharmacological inhibition of NF-κB activity. CONCLUSION These results uncover a regulatory signaling,NF-κB/LIN28 B,which plays a pivotal role in leukemia stem cell-like properties and it could serve as a promising intervening target for effective treatment of AML disease.

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.

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.

High frequency of CD34+CD38-/low immature leukemia cells is correlated with unfavorable prognosis in acute myeloid leukemia

AIM To evaluate the importance of the CD34+CD38-cell population when compared to the CD34+CD38+/low and CD34+CD38+/high leukemic cell sub-populations and to determine its correlations with leukemia characteristics and known prognostic factors, as well as with response to therapy and survival.METHODS Two hundred bone marrow samples were obtained at diagnosis from 200 consecutive patients with newly diagnosed acute myeloid leukemia(AML) were studied between September 2008 and December 2010 at our Institution(Hematology Department, Lyon, France). The CD34/CD38 cell profile was analyzed by multiparameter flowcytometry approach using 8 C panels and FACS CANTO and Diva software(BD Bioscience).RESULTS We analyzed CD34 and CD38 expression in bone marrow samples of 200 AML patients at diagnosis, and investigated the prognostic value of the most immature CD34+CD38-population. Using a cut-off value of 1% of CD34+CD38-from total "bulk leukemic cells" we found that a high(> 1%) level of CD34+CD38-blasts at diagnosis was correlated with advanced age, adverse cytogenetics as well as with a lower rate of complete response after induction and shorter disease-free survival. In a multivariate analysis considering age, leukocytosis, the % of CD34+ blasts cells and the standardized cytogenetic and molecular risk subgroups, a percentage of CD34+CD38-leukemic cells > 1% was an independent predictor of DFS [HR = 2.8(1.02-7.73), P = 0.04] and OS [HR = 2.65(1.09-6.43), P = 0.03].CONCLUSION Taken together, these results show that a CD34/CD38 "backbone" for leukemic cell analysis by multicolour flowcytometry at diagnosis provides useful prognostic information.

Study on Taxol in Inhibiting Human Leukemia Cell Proliferation andInducing Apoptosis

Objective: To explore the effects of Taxol in inhibiting human leukemia k562 cell proliferation and inducing apoptosis in vitro. Methods: Human leukemia K562 cells were treated with Taxol of different concentrations for 12-72 hrs. Cell proliferation was evaluated by MTT assay and morphological changes of apoptosis were examined by microscopy. Cell apoptosis was determined by flow cytometry (FCM) and DNA gel electrophoresis. Results: Growth of K562 cells was inhibited by Taxol with an IC50 value of 0. 84μg/ml. Typical nuclear condensation and apoptosis bodies were observed as early as 24 hrs after a 0.5μg/ml Taxol treatment; Apoptotic rate of the Taxol-treated K562 cells increased from 3.7% to 24.0% in 24 hrs. No DNA ladder was observed by DNA gel electrophoresis. Conclusion: Taxol could inhibit K562 cell growth and induce apoptosis in vitro.

EFFECTS OF PML AND PML/RMRα ANTISENCE OLIGO-NUCLEOTIDE ON PROMYELOCYTIC LEUKEMIA CELL NB4

Objective: To investigate the effects of anti-PML (promyelocytic leukemia) or anti-PML/RAR( (promyelocytic leukemia/retionic acid receptor() antisense oligonucleotides on cell growth, expression of PML-RAR( mRNA and PML-RAR(/PML protein location of NB4 cell lines. Methods: RT-PCR was used for detecting PML-RAR( mRNA expression, trypan blue exclusion for cell count, methylcellose assay for leukemic colony forming unit detection, immuno- fluorescence for PML-RAR(/PML protein location. Results: Both anti-PML start codon region antisence (STAS) and anti-PML-RAR( fusion region antisence (FUAS) could inhibit cell growth and the formation of acute myelocytic colony forming unit of cells(AML-CFU). Cells become partial differentiated at days 5, being more obvious in FUAS-treated cells than in STAS ones. Down regulation of PML-RAR( mRNA expression occurred at 24 hours in STAS and FUAS-treated cells and maintained for up to 72 hours. Immuno-fluorescence analysis with anti-PML monoclonal antibody showed a remarkable decrease even complete disappearance of microgranules. The residual granules became enlarged as discrete dots (<10 per cell), similar to normal POD structure in some STAS-treated cells at 24 hours. At 72 hours, nearly all the granules disappeared. Similar changes were observed in FUAS-treated cells. Conclusion: Both PML and PML-RAR( antisence oligonucleotides can specially block the expression of PML-RAR( at mRNA and protein levels. PML protein is implicated in the regulations of cell differentiation.

A novel mouse model of adult T-cell leukemia cell invasion into the spinal cord

Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg-Prkdc~ (scid) Il2 rg ^(tm1Wjl)/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly(I.M.) at 5 weeks of age, 8(80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously(S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV-1-specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV-1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement.

Acute myeloid leukemia cells inhibit the differentiation and maturation of dendritic cells and induce the generation of regulatory T cells

Objective:To investigate the effects of soluble factors secreted by acute myeloid leukemia(AML) cells on the phenotypical and functional properties of DCs derived from normal mononuclear cells. Methods:Mononuclear cells were cul-tured with interleukin-4(IL-4) and granulocyte-macrophage colony-stimulating factor(GM-CSF),in the presence or absence of 24 h culture supernatants from fresh primary AML cells,to generate immature DCs. The maturation of DCs was induced by cytokines IL-1beta,IL-6,tumor necrosis factor-alpha(TNF-alpha),and prostaglandin-2(PGE-2). The phenotypic alterations of DCs and DCs-primed CD4+ T cells were evaluated using flow cytometry. Precursor frequency(PF) was calculated to monitor the allostimulatory effects of DCs on CD4+ and CD8+ T cells. Results:AML cell supernatant-treated DCs showed significantly lower expression of co-stimulatory molecules CD80 and CD86,and reduced response to cytokines IL-1beta,IL-6,TNF-alpha,and PGE-2. The allostimulatory effects of AML cell supernatant-treated DCs on CD4+ and CD8+ T cells were significantly lower than those of normal mature DCs [PF:(1.8 ± 0.5)% vs.(5.2 ± 1.6)% for CD4+ T cells,(2.1 ± 0.6)% vs.(6.5 ± 2.0)% for CD8+ T cells,P < 0.01]. These AML supernatant-induced DCs could also induce allogeneic CD4+ T cells to differentiate into CD4+CD25high T cells,which had immunophenotyping characteristics of regulatory T cells,i.e. they expressed Foxp3 but not active maker CD69. Conclusion:This study demonstrates that soluble factors secreted by AML cells can inhibit development and functions of DCs. In addition,AML supernatant-induced DCs can induce the generation of CD4+CD25high T cells from CD4+ T cells,which may be a mechanism of increased prevalence of CD4+CD25high regulatory T cells and immune dysfunction in AML patients.

Inhibitory Effect of Histone Deacetylase Inhibitor on the Proliferation of Leukemia Cells and Its Anti-Tumor Pharmacology

The aim of this study was to explore the inhibitory effect of histone deacetylase inhibitor (HDACI) on the proliferation of leukemia cells. The two kinds of leukemia cells (human promyelocytic leukemia cell (HL-60) and human acute myelogenous leukemia cell (KG-1)) were selected for in vitro research. Besides, Chidamide, a kind of benzamide HDACI, was applied to induce and culture the HL-60 and KG-1 cells, and the anti-tumor cell proliferation activity of Chidamide on HL-60 and KG-1 was detected by the methyl thiazolyl tetrazolium (MTT) assay, which was 5.6 and 6.1 in turn. The cell scratch experiment verified that Chidamide had the metastasis inhibitory effect on HL-60 and KG-1 cells. Flow cytometry was employed to measure the percentage of apoptotic cells, and it was found that the percentage of apoptotic cells was 55.6% ± 1% and 48.6% ± 1% in sequence after HL-60 and KG-1 cells were treated with Chidamide for 36 hours. The number of auto-phagosomes was determined by transmission electron microscopy showing that the number of auto-phagosomes in HL-60 and KG-1 cells was 12 ± 1 and 10 ± 1, respectively after the induction process of Chidamide. The phosphorylated histone H2AX protein (γ-H2AX) recognition antibody immunofluorescence method was adopted to determine the deoxyribonucleic acid (DNA) damage, and the positive rates of HL-60 and KG-1 cells reached 28.41% and 26.35%, respectively after Chidamide treatment. Therefore, Chidamide, as a kind of HDACI, could effectively inhibit the proliferation of leukemia cells, so that the results of this experiment had a good guiding meaning for the clinical diagnosis and treatment of leukemia.

Treatment refractory mast cell leukemia with dominant gastrointestinal manifestation and concomitant skin symptoms:A case report

BACKGROUND Mast cell leukemia(MCL),a subtype of systemic mastocytosis(SM),is an extremely rare clinical entity characterized by a very poor prognosis.Chemotherapy,tyrosine kinase inhibitors,and allogeneic hematopoietic cell transplantation are the only treatment options,but they cannot provide the desired outcomes in most cases of MCL.However,other types of SM can be successfully treated.The disease has no specific manifestation,but gastroenterological symptoms are present in most cases.CASE SUMMARY The authors,hereby,report a case of a 46-year-old female patient diagnosed with MCL-the rarest subtype of SM.The patient presented to the gastroenterology clinic with multiple,various,and unspecific gastroenterological symptoms.Concomitance of skin lesions significantly contributed to a relatively prompt diagnosis.The serum tryptase level was extremely high and bone the marrow aspirate showed an infiltration of atypical mast cells.The disease was rapidly progressive and primary refractory to chemotherapy and the patient succumbed to the illness about a month after the initiation of treatment.CONCLUSION Despite its“hematological nature”,MCL,in most cases presents dominantly with unspecific gastroenterological symptoms.Thus,a high disease awareness among physicians other than hematologists is necessary to improve treatment outcomes.Serum tryptase level,due to its non-invasive nature and easy access,may serve as an initial step to estimate the probability of mastocytosis.

Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction

BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

Bortezomib-Induced Bilateral Eye Swelling and Cutaneous Adverse Reaction in a Patient with Plasma Cell Leukemia—A Case Report

Bortezomib, a proteasome inhibitor, is an established therapy against plasma cell leukemia—a variant of plasma cell dyscrasias. Its most frequent side effects have been listed as peripheral neuropathy, neuropathic pain, thrombocytopenia, and gastrointestinal problems. Allergic skin reaction is a rarely documented side effect in patients receiving bortezomib-based chemotherapy. A combination therapy consisting of intravenous bortezomib, oral Revlimid tablets, and oral dexamethasone tablets has been prescribed for the patient after his recent diagnosis of plasma cell leukemia. While receiving his third treatment cycle, he developed an allergic reaction (skin rash) involving the neck, and wrists, and mild bilateral eye swelling. The infusion was stopped immediately and then ciprofloxacin ophthalmic solution and oral diphenhydramine 25 mg were prescribed to the patient with significant improvement in his clinical condition. He was temporarily taken off bortezomib. At a follow-up visit a week later, a significant improvement was noticed in his condition. Rash had reduced on neck and wrists, and eye swelling had reduced as well. As of the time of writing this case report, he has been temporarily taken off bortezomib, but other medications in the treatment regimen were continued as prescribed.

From Myeloma to Plasma Cell Leukemia, Persistent Inequalities

Multiple myeloma (MM) is both a complex and heterogeneous disease. Cytogenetic and molecular abnormalities lead to resistance to treatment and transformation to plasma cell leukemia, which is defined by the presence in circulating blood of plasma cells over 2 G/L, or more than 20% of leukocytes. It is an uncommon hematological malignancy with a poor prognosis. Against this backdrop, we report an observation of multiple myeloma transformed into plasma cell leukemia diagnosed at the Hôpital Principal de Dakar (HPD) that occurred on a 64-year-old man with a history of thyroidectomy followed for multiple myeloma presenting with Salmon et Durie stage IIIA and ISS stage I. Despite a marked improvement in management strategy, myeloma remains an almost invariably incurable disease. However, the development of genetic and molecular biomarkers is necessary to improve its prognosis.