Effects of high-dose dexamethasone on regulating interleukin-22 production and correcting Th1 and Th22 polarization in immune thrombocytopenia.

BACKGROUND: T-cell dysregulation and T-cell-related cytokine abnormalities are involved in the pathogenesis of immune thrombocytopenia (ITP). One of our previous studies showed that elevated IL-22 correlated to Th1 and Th22 cells plays an important role in the immunopathogenesis of ITP. In this study, we aimed to investigate the effects of high-dose dexamethasone(HD-DXM) on IL-22 production and on the IL-22-producing T-cell subsets in ITP patients. METHODS: IL-22 plasma levels and the percentages of Th1, Th17, and Th22 cells were determined by enzyme-linked immunosorbent assay and flow cytometry in 25 ITP patients receiving DXM 40 mg/day for 4 consecutive days. RESULTS: Plasma IL-22 concentrations and the percentages of Th1 and Th22 cells were significantly increased in pretherapy patients relative to controls (P<0.05), but the percentage of Th17 cells was not. HD-DXM administration reduced IL-22 production and corrected the imbalance between Th1 and Th22 subsets. IL-22 levels were positively correlated with Th1 and Th22 cells in ITP patients before and after HD-DXM treatment. CONCLUSION: These results suggest that HD-DXM may regulate the production of IL-22 in ITP, possibly by correcting Th1 and Th22 polarization.

The Regulatory Function of ADAR1-mediated RNA Editing in Hematological Malignancies / 生物化学与生物物理进展

RNA editing, an essential post-transcriptional reaction occurring in double-stranded RNA (dsRNA), generates informational diversity in the transcriptome and proteome. In mammals, the main type of RNA editing is the conversion of adenosine to inosine (A-to-I), processed by adenosine deaminases acting on the RNAs (ADARs) family, and interpreted as guanosine during nucleotide base-pairing. It has been reported that millions of nucleotide sites in human transcriptome undergo A-to-I editing events, catalyzed by the primarily responsible enzyme, ADAR1. In hematological malignancies including myeloid/lymphocytic leukemia and multiple myeloma, dysregulation of ADAR1 directly impacts the A-to-I editing states occurring in coding regions, non-coding regions, and immature miRNA precursors. Subsequently, aberrant A-to-I editing states result in altered molecular events, such as protein-coding sequence changes, intron retention, alternative splicing, and miRNA biogenesis inhibition. As a vital factor of the generation and stemness maintenance in leukemia stem cells (LSCs), disordered RNA editing drives the chaos of molecular regulatory network and ultimately promotes the cell proliferation, apoptosis inhibition and drug resistance. At present, novel drugs designed to target RNA editing(e.g., rebecsinib) are under development and have achieved outstanding results in animal experiments. Compared with traditional antitumor drugs, epigenetic antitumor drugs are expected to overcome the shackle of drug resistance and recurrence in hematological malignancies, and provide new treatment options for patients. This review summarized the recent advances in the regulation mechanism of ADAR1-mediated RNA editing events in hematologic malignancies, and further discussed the medical potential and clinical application of ADAR1.

The effect of platelet infusion on the repair of bone marrow hematopoietic niche damage in mice induced by (60)Co radiation and hematopoietic reconstruction after bone marrow transplantation / 中华血液学杂志

Objective: To observe the effect of platelets on hematopoietic stem cell (HSCs) implantation in mice with radiation-induced bone marrow injury and bone marrow transplantation models. Methods: ①Male C57BL/6 mice were divided into a single irradiation group and a radiation infusion group after receiving (60)Co semimyeloablative irradiation for 18-10 weeks. The irradiation infusion group received 1×10(8) platelets expressing GFP fluorescent protein. ② The allogeneic bone marrow transplantation model was established. The experimental groups included the simple transplantation group (BMT) and the transplantation infusion group (BMT+PLT). The BMT group was infused through the tail vein only 5 × 10(6) bone marrow cells, the BMT+PLT group needs to be infused with bone marrow cells at the same time 1× 10(8) platelets. ③ Test indicators included peripheral blood cell and bone marrow cell counts, flow cytometry to detect the proportion of hematopoietic stem cell (HSC) and hematopoietic progenitor cells, bone marrow cell proliferation and apoptosis, and pathological observation of vascular niche damage and repair. Results: ①On the 3rd, 7th, 14(th), and 21st days after irradiation, the bone marrow cell count of the infusion group was higher than that in the single irradiation group (P<0.05), and the peripheral blood cell count was also higher. A statistically significant difference was found between the white blood cell count on the 21st day and the platelet count on the 7th day (P<0.05). In the observation cycle, the percentage of bone marrow cell proliferation in the infusion group was higher, while the percentage of apoptosis was lower. ② The results of bone tissue immunofluorescence after irradiation showed that the continuity of hematopoietic niche with red fluorescence was better in the irradiation infusion group. ③The chimerism percentage in the BMT+PLT group was always higher than that in the BMT group after transplantation.④ The BMT+PLT group had higher bone marrow cell count and percentage of bone marrow cell proliferation on the 7th and 28th day after transplantation than that in the BMT group, and the percentage of bone marrow cell apoptosis on the 14th day was lower than that in the BMT group (P<0.05). After the 14th day, the percentage of stem progenitor cells in the bone marrow cells of mice was higher than that in the BMT group (P<0.05). ⑤The immunohistochemical results of bone marrow tissue showed that the continuity of vascular endothelium in the BMT+PLT group was better than that in the BMT group. Conclusion: Platelet transfusion can alleviate the injury of vascular niche, promotes HSC homing, and is beneficial to hematopoietic reconstruction.

Effects of Combined Infusion of Mesenchymal Stem Cells and Endothelial Progenitor Cells on Lung Injury after Hematopoietic Stem Cell Transplantation / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of combined infusion of mesenchymal stem cells (MSC) and endothelial progenitor cells (EPC) on lung injury after hematopoietic stem cell transplantation (HSCT).@*METHODS@#The experiment was divided into normal control group, irradiation group, bone marrow cell transplantation group (BMT group), BMT+EPC group, BMT+MSC group and BMT+EPC+MSC group. The model of HSCT was established, on the 30th day after transplantation, the mice were sacrificed. Then lung tissue was taken for testing. The mRNA expression levels of VEGF, IL-18, IL-12b were detected by RT-PCR, and protein expression level of NLRP3 was detected by Western blot. The expression of MPO and CD146 was observed by immunohistochemistry assay.@*RESULTS@#The expression level of VEGF gene in BMT+EPC+MSC group was significantly higher than that in other groups (P＜0.01). The expression level of IL-18 and IL-12b gene was the highest in BMT group and the lowest in BMT+EPC+MSC group, and the difference was statistically significant (P＜0.05). HSCT could increase the expression of NLRP3 protein, and the BMT+EPC+MSC could significantly reduce the level of NLRP3 protein in lung cells, tending to normal. Compared with normal tissues, the BMT+EPC+MSC could improve the lung tissue structure more effectively, the expression of MPO positive cells was lower, and the expression of VEGF positive cells was higher.@*CONCLUSIONS@#The combined infusion of MSC and EPC can promote capillary regeneration, alleviate inflammation and promote lung repair after HSCT, which is superior to single EPC or MSC infusion.

Role of Ca-NFAT Signaling Pathway in Ph ALL Drug-resistance Mediated by Bone Marrow Stromal Cells / 中国实验血液学杂志

OBJECTIVE@#To explore the role of Ca-NFAT signaling pathway in Ph-ALL drug resistance mediated by bone marrow stromal cells.@*METHODS@#The transcription level of NFAT mRNA in Sup-B15 cells and Ph ALL primary cells was detected by polymerase chain reaction. The expression of P-glycoprotein in Sup-B15 cells was detected by flow cytometry. The change of NFAT protein in Sup-B15 cells was detected by Western blot. AnnexinV/7-AAD was used to label cells. Flow cytometry was used to detect cell apoptosis; Fluo 3-AM dye was used to label cells, and flow cytometry used to detect changes of Ca concentration in leukemia cells.@*RESULTS@#NFAT expression could be detected in both Sup-B15 and Ph ALL primary cells; P-glycoprotein could not be detected by flow cytometry; CAS could significantly inhibit NFAT protein expression in clinically applied drug concentrations (2.5, 5 μmol/L); Clinically applied concentration of CAS (2.5, 5 μmol / L) has no significant effect on the apoptosis of Sup-B15 cells, while higher concentration of CAS (10 μmol / L) could induce apoptosis of Sup-B15 cells. Bone marrow stromal cells OP9 could, decrease the sensitivity of Sup-B15 cells and Ph ALL primary cells to imatinib (IM); After co-culture with bone were marrow stromal cells, the Ca concentration in Sup-B15 cells was enhanced, the levels of NFAT protein and nullear protein in sup-B15 cells also were enhanced. The addition of CAS in co-culture system could inlibit the Ca-NFAT signaling pathway, reduce the protective effect of OP9 on Sup-B15 cells.Conclution:The Ca-NFAT sigualing pathway, contributes to the survival of Ph ALL cells. Bone marrow stromal cells can mediate the resistance of Ph ALL cells to IM by activating Ca-NFAT signaling pathway.

Effect of Stably Down-regulating FMI Expression of K562 Cells on Sensitivity of K562 cells to Imatinib Mesylate / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of stably down-regulating the FMI expression of K562 cells on the sensitivity of K562 cells to Imatinib (IM) and its possible mechanism.@*METHODS@#Western-blot was used to detect the expression of FMI protein in K562 cells and peripheral blood mononuclear cells from the patients with chronic myelogenous leukemia, chronic myeloid blast crisis and healthy volunteers. The specific interference sequences targeting at the human FMI gene were designed and ligated into the lentiviral vector LV3; the three plasmid system-packaged lentivirus particles were used to transfect K562 cells to screen K562 cells that stably down-regulated FMI. CCK-8 assay and flow cytometry were used to determine effect of IM on cell proliferation and apoptosis. The transcription level of FMI and Fz8 in leukemia cells was detected by fluorescent quantitative PCR. The protein expression levels of FMI, Fz8, NFAT1, BCR-ABL and β-catenin in leukemia cells were detected by Western-blot.@*RESULTS@#The expression of FMI protein could be detected in peripheral blood mononuclear cells of the patients with CML-BC and K562 cells, the FMI expression could not be detected in all the patients with CML-CP and healthy volunteers. The recombinant lentiviral vector LV3/FMI had been successfully constructed the lentivirus was packaged, and the K562 cells stably down-regulating the FMI protein were screened. After stable down-regulation of FMI expression in K562 cells, the proliferation rate of leukemia cells decreased and the apoptosis rate was increased under the same drug concentration. Both the transcription and protein expression levels of Fz8 decreased. The NFAT1 total protein level increased, as well as the nuclear translocation of protein was enhanced. There was no significant change in the expression level of BCR-ABL fusion protein. The expression level of β-catenin protein decreased.@*CONCLUSION@#After the stable down-regulation of FMI expression, the sensitivity of K562 cells to IM and apoptosis of cells increase, which are performed possibly by inhibiting the FMI-Fz8 signaling pathway and activating the Ca-NFAT and Wnt/β-catenin signaling pathway.

Relationship between NLRP1 and Liver Dysfunction Following Allogeneic Hematopoietic Stem Cell Transplantation / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect of NLRP1 on the liver dysfunction following allogeneic hematopoietic stem cell transplantation(allo-HSCT).</p><p><b>METHODS</b>The mouse model of allo-HSCT was established by using C57BL/6 and NLRP mice were used as the recipients: BABL/c mice were used as donors). The chimera rates of donor's bone marrow cells were assayed by flow cytometry. ALT and AST levels were measured by automatic biochemical analyzer. Western blot was used to detect the expressions of NLRP1, the precursor of Caspase-1 and its active segment p20,IL-1β,IL-18 and MPO in livers.</p><p><b>RESULTS</b>The chimera rate was over 96% on the day 14 after allo-HSCT, and showed that the hematopoietic stem cells of donors had been transplanted into recipients. ALT and AST levels were increased from (173.9±12.39)U/L and (283.7±28.00)U/L on day 7 to (3902±1745)U/L and (5316±924)U/L on the day 14 and decreased to (3153±564.4) U/L and (4350±957.7) U/L on the day 28, respectively. Western blot showed that the expression of NLRP1 was increased after allo-HSCT, which displayed a similar trend with the changes of ALT and AST. When knocking out NLRP1, the contents of ALT and AST in the knocked group were significantly decreased in comparison with the group without knocking out. And the expression levels of NLRP1 related inflammatory proteins, precursor of Caspase-1,p20,Mature-IL-1β,Mature-IL-18 and MPO were lower than those in groups without knocking out NLRP1 gene.</p><p><b>CONCLUSION</b>Allo-HSCT can cause the damage of liver function and increase the expression of NLRP1, while knocking out NLRP1 can reduce the damage of liver function, so NLRP1 may be one of the important factors leading to liver dysfunction.</p>

Effect of Steadily Down-regulating VE-Cadherin Expression on Susceptibitity of K562 Cells to Chemotherapy / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of steadily down-regulating the expression of VE-cadherin on the chemotheraputic sensitivity of K562 cells, and explore its possible mechanism.</p><p><b>METHODS</b>Specifically targeting interference sequences carrying human VE-cadherin were designed, the recombinant lentiviral vector containing the IRES-GFP and NEO segment was constructed; recombinant lentivirus was generated by three-plasmids packing system, and transfected into K562 cells, then the cells steadily down-regulated were sorted. CCK-8 assay was performed to evaluate the VE-cadherin of chemotherapeutic (Imatinib) sensitivity of K562 cells. The apoptosis was analyzed by flow cytometry with Annexin V/7-AAD double labeling. The expressions of CD133 and ALDH1 mRNA were determined by real time PCR. The protein expressions of VE-cadherin, BCR-ABL and β-catenin were analyzed by Western blot.</p><p><b>RESULTS</b>The recombinant lentiviral vector pLB-shVEC-NEO-IRES-GFP was successfully constructed, packed into the lentivirus, then the K562 cells steadily down-regulating VE-cadherin expression was obtained. When VE-cadherin was down-rengulated in K562 cells, the proliferation rate was reduced while the the apoptosis rate was increased; the mRNA levels of CD133 and ALDH1 also were reduced; BCR-ABL fusion protein was not obviously changed; the total β-catenin protein, as well as the nuclear β-catenin protein were decreased in the K562/shVEC cells. Conclution: K562 cells are more susceptible to chemotherapy when VE-cadherin is down-regulated, that may be realized via reducing the stability and the nuclear transfer of β-catenin protein.</p>

Relationship between BCR-ABL and Prognosis and Affecting Factors for Prognosis in CML Patients Treated with TKI for 12 Months / 中国实验血液学杂志

@#<p><b>OBJECTIVE</b>To evaluate the long-term prognosis of CML patients whose BCR-ABL transcript level was warning and best response at 12 months of treatment with tyrosine kinase inhititor (TKI), and to investigate the factors affecting therapeutic efficacy and prognosis.</p><p><b>METHODS</b>The clinical data of patients with newly diagnosed CML were analyzed retrospectively. According to BCR-ABL transcript level, the 80 patients were divided into group A and group B, the patients with BCR-ABL >0.1% and ≤ 1% (warning response) were entolled in group A, and the patients with BCR-ABL ≤ 0.1% (best response) were enrolled in group B as control. The ratio of patients with main molecular response (MMR) and deep molecular response (DMR), as well as aquistation rate and cummulative rate of MR (DMR) at specified fine points in 2 groups were compared, the independent risk factors affecting the therapeutic efficacy and prognosis were analyzed.</p><p><b>RESULTS</b>The MMR and MR of the B group at 15, 18 and 24 months after TKI treatment were significantly higher than those of the A group, and the patients in the B group reached MR faster. In the 3 months, 6 months and 12 months after the demarcation point (TKI 12 months), the A group was much less easy to obtain MR (P<0.05) than the B group. Through survival analysis, there were more patients in the B group than the A group at different time points to reach MR, and the difference was statistically significant (P<0.01). The single factor analysis showed that the splenomegaly (below rib edge)> 10cm (P<0.01) and lactate dehydrogenase > 400 U/L (P<0.05) were the long-term warning factors for patients. Multivariate analysis showed that the size of the spleen was an independent factor (P<0.01) to affect the prognosis of the patients who had been warned for 12 months.</p><p><b>CONCLUSION</b>Patients at 12 months warning effect are slower and less easier to get DMR, which has a poor long-term prognosis. The size of the spleen in the patient at warning for 12 months of treatment effect can predict the relatively poor long-term prognosis. For a patient with a 12 months response to the warning, an early replacement therapy is available on the basis of combining other factors..</p>

Caspase1 Inhibitor Ac-YVAD-CMK Prevents and Treats the Acute Graft Versus Host Disease in Mice / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect of Caspase 1 inhibitor Ac-YVAD-CMK on acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation(allo-HSCT) and its mechanism.</p><p><b>METHODS</b>Experiments were divided randomly into 3 groups: allogeneic hematopoietic stem cell transplantation combined with splenic cell infusion group (TS group, n=12), allogeneic hematopoietic stem cell transplantation combined with splenic cell infusion plus injection of low dose Caspase 1 inhibitor group (TS+low dose of C group, n=16) and plus high dose Caspase1 inhibitor (TS+high dose of C group, n=19). The body weight of mice in each group was dynamically detected, and the clinical manifestation of GVHD and score of aGVHD were determined, and the chimerism rate of mice was detected after transplantation for 14 days. Th1, Th2 and Th17 cells in peripheral blood were examined by flow cytometry. Peripheral proinflammatory cytokines IL-1β, IFN-γ, IL-1α and IL-18 were examined by enzyme-linked immunosorbent assay(ELISA). The tissues sections of GVHD target organs (liver, lung, colon and skin) were stained with HE for histopathologic examination and histopathologic score.</p><p><b>RESULTS</b>Ac-YVAD-CMK could alleviate murine aGVHD and pathological injury, decreare the incidence and severity of aGVHD in recipient mice. The detection of Th cell subsets in peripheral blood by flow cytometry showed that compared with TS group, the Th1 cell ratio in TS+low dose of C and TS+high dose of C groups was significantly reduced (P<0.05), while the Th2 and Th17 cell ratio was significantly enhanced (P<0.05) in TS+low dose of high dose of C groups. The detection of peripheral inflamematory cytokines by ELISA demonstrated that the inflammatory cytokines including IL-1β,IFN-γ,IL-18 and IL-1α were reduced significantly (P<0.05).</p><p><b>CONCLUSION</b>Ac-YVAD-CMK can improve aGVHD by inhibiting Caspase 1 and reducing the release of some inflammatory cytokines, thereby alleviated the aGVHD pathological damage.</p>

Research Progress on Endothelial-Cell Injury in the Acute Graft-Versus-Host Disease / 中国实验血液学杂志

Recently there are increasing evidence of the existence of an immune-mediated endothelial-cell injury in the acute graft-versus-host disease (aGVHD). Endothelial cells are an important target in the process of GVHD immune attacking, and vascular end thelial injure is an early event of tissue injury caused by aGVHD after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Biomarkers for endothelial damage were consisted with endothelia injury, which may be considered a valuable marker to confirm GVHD diagnosis. The endothelial cell phenotype differs between organs, which results in organ-dependent differences for the involved organs when GVHD occurring. Although the endothelial cells play an impartant tole in process of aGVHD occurence, a further research to better characterize its role in allo-HSCT is needed. This review focusses on the research progress of aGVHD after allo-HSCT and endothelial-cell injury, as well as is markers so as to provide corresponding strategies and targets for the prevent and treatment of a GVHD.

Research Progress on Roles of Platelets in Tissue Repair -Review / 中国实验血液学杂志

Platelets are known to play a critical role in thrombosis and hemostasis. However, recent studies demonstrated that beyond their role in thrombosis and hemostasis, platelets are also involved in the regulation of tissue repair and regeneration. Increasing number of studies on the roles of platelets in tissue repair showed that various growth factors, chemokines as well as cytokines secreted from activated platelets regulate injured tissue repair and regeneration with the main mechanisms being through regulation of cell migration, proliferation, and angiogenesis, cell apoptosis and survival. Deeply understanding the molecular mechanism of tissue repair induced by platelets might promote their application in clinic. This review discusses the structure and function of platelets, the mechanism of platelet-induced tissue repair as well as clinical application of platelets.

Effect of has-miR-150 on proliferation and apoptosis of Jurkat cells and its mechanism / 中国实验血液学杂志

<p><b>OBJECTIVE</b>This study was to investigate the effect of has-miR-150 on the proliferation and apoptosis in human acute T lymphocytic leukemia (T-ALL) cell line Jurkat, and explore its mechanism.</p><p><b>METHODS</b>Lentivirus-has-miR-150 was constructed and transfected to Jurkat cells. The expression of miR-150 was detected by real time PCR; the cell proliferation and apoptosis were detected by CCK-8 method and Annexin V/7-AAD labeling, respectively; the cell-related protein expressions of phosphatidylinositol-3-kinase(PI3K)/serine/ threonine kinase (Akt) signaling pathway were detected by Western blot.</p><p><b>RESULTS</b>The expression of miR-150 in infected Jurkat cells was significantly upregulated by constructing lentivirus-has-miR-150. Compared to negative control (transfected with empty-vector lentivirus), the cell proliferation after LV-miR-150 transfection was significantly inhibited and cell apoptosis was remarkably induced. Phosphorylation levels of P13K/Akt/NF-κB signaling pathway protein p-Akt and p-p65 decreased,whereas no obvious change was found in the expression of Akt.</p><p><b>CONCLUSION</b>miR-150 may be a putative oncoprotein in T-ALL cells. Overexpression of miR-150 has noticeable effects on the proliferation inhibition and apoptosis induction of Jurkat cells, which may be mediated by the negative regulation of PI3K/Akt /NF-κB signaling pathway.</p>

Significance of Th1/Th17 Imbalance in Mice with Acute Graft-versus-Host Disease / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effects of Th1/Th17 cell imbalance on the pathogenesis of acute graft-versus-host disease (GVHD) in mice.</p><p><b>METHODS</b>In a murine GVHD model of C57BL/6 (H-2(b)), a low dose of halofuginone (HF) was applied for treating the recipients in order to result in Th1/Th17 imbalance. Rechipient mice were divided into GVHD group (without HF intervention) and GVHD plus HF group (treated by HF). The recipients were monitored for survival rate, clinical scores of acute GVHD, contents of circulatory Th1 and Th17 cells, Th1/Th17 ratio and serum level of IFN-γ and IL-17A. Expression levels of IFN-γ and IL-17A in target organs were analyzed by using real-time PCR, and the target organs were delivered for histological examinations.</p><p><b>RESULTS</b>Recipients treated with HF showed that all the mortality, circulatory Th1/Th17 ratio and clinical score were higher than those in the mice without HF intervention (P < 0.05). Circulatory Th1/Th17 ratio positively correlates with clinical score (P < 0.001). HF administration reduces the expression level of intestinal IL-17A and increases intrahepatic and intestinal IFN-γ level (P < 0.05), HF treatment aggravates GVHD in liver and small intestine with augmented hepatic and intestinal inflammation.</p><p><b>CONCLUSION</b>Th1/Th17 imbalance contributes to the pathogenesis of acute GVHD.</p>

Effect of Alantolactone on Proliferation of RPMI-8226 Cells and Its Possible Mechnism / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of alantolactone on perliferation and apoptosis of multiple myeloma (MM) RPMI-8226 cells, and to explore its possible mechism in vitro and in vivo.</p><p><b>METHODS</b>The RPMI-8226 cells were treated with alantolactone (1, 2.5, 5, 7.5 and 10 µmol/L) for 48 h, cell viability was detected by CCK-8 assay and the value of IC50 was calculated; The RPMI-8226 cells were treated with alantolactone (2.5, 5 and 7.5 µmol/L) for 48 h, the apoptotic rate was detected by flow cytmetry with Annexin V/PI staining; the expression level of cleaved caspase-3 and phosphorylation of ERK were measured by Western blot; the nude mice was used to further confirm the proapoptotic effect of alantolactone on MM cells in vivo.</p><p><b>RESULTS</b>The alantolactone inhibited RPMI-8226 cell viability remarkably with a dose-dependent manner; the IC50 value of RPMI-8226 cells at 48 h was 4.32 ± 0.15 µmol/L; the apoptotic rate increased observably with a dose-dependent manner; the levels of cleaved-caspase-3 increased and the phosphorylation of ERK decreased significantly; as compared to control, the volum of tumor was much smaller, the expression levels of Ki67 and p-ERK decreased.</p><p><b>CONCLUSION</b>The alantolactone can efficiently inhibit the proliferation and induce the apoptosis of multiple myeloma RPMI-8226 cells in vitro and in vivo through inhibiting the activation of ERK signal pathway.</p>

Effect of ADAM10 Inhibitor GI254023X on Proliferation and Apoptosis of Acute T-Lymphoblastic Leukemia Jurkat Cells In Vitro and Its Possible Mechanisms / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of ADAM10 inhibitor GI254023X on the proliferation and apoptosis of acute T-lymphoblastic leukemia Jurkat cells and its mechanisms.</p><p><b>METHODS</b>Jurkat cells were treated with different concentrations of GI254023X, the proliferation-inhibition curve was assayed and plotted by CCK-8 method, the cell viability and apoptosis was detected by flow cytometry with Annexin V and 7-AAD staining, the cleavage of Notch1 protein was determined by Western blot, the transcripts of anti-apoptotic genes BCL-2, MCL-1, BCL-xl and Notch1 target gene Hes-1 were detected by real-time PCR.</p><p><b>RESULTS</b>The GI254023X obviously inhibited the proliferation of Jurkat cells in concentration-dependent manner. As compared with the control group, the apoptosis of cells increased along with increment of GI254023X concentration. Compared with control group, the expression of Cleaved Notch1 was down-regulated while the expression of Notch1 was up-regulated in a time-dependent manner after the treatment with GI254023X. The levels of MCL-1 and Hes-1 mRNA transcripts in Jurkat cells were reduced in GI254023X treated group, but did not show obvious effect on the level of BCL-2 and BCL-xl mRNA transcripts.</p><p><b>CONCLUSION</b>GI254023X can remarkably inhibit proliferation and induce apoptosis of Jurkat cells. The inhibition of Notch1 activation and the down-regulation of apoptosis-related gene MCL-1 may be involved in the process of apoptosis.</p>

Roles of NLRP1 in blood diseases / 中国实验血液学杂志

The inflammasome is a group of multiprotein complexes in the cytoplasm, which can activate caspase-1 that mediates the maturation and release of IL-1β, IL-18, IL-33 and other pro-inflammatory cytokines.NALP1 (NACHT leucine-rich-repeat protein 1), also known as NLRP1, is the first one of the identified complex inflammasomes with definite ligands mainly involved in the activation of inflammasome assembly and the formation of apoptotic bodies. Moreover, it was also found that NLRP1 plays an important biological role in the development of acute leukemia, the bone marrow hematopoietic stem cell apoptosis and other blood diseases. This review briefly summarizes the structure, activation mechanism, regulation and the role of NLRP1 in the hematopoietic system.

Effect of AZD8330 on proliferation and apoptosis of multiple myeloma cells / 中国实验血液学杂志

This study was aimed to investigate the effect of MEK inhibitor AZD8330 on proliferation and apoptosis of multiple myeloma IM9 and NCI-H929 cell lines and its possible mechanism. These two cell line cells were exposed to different concentrations of AZD8330 for 48 h. The CCK-8 assay was used to detect cell viability and the IC50 value at 48 h. These above-mentioned IM9 and NCI-H929 cells were treated with 5,10 and 100 nmol/L of AZD8330, then the change of cell cycle was analysed by flow cytometry with PI staining. The Wester blot was used to detect the expression levels of cyclin D and cyclin E, and multiple myeloma cells were treated with 10, 100, 1000 and 2000 nmol/L of AZD8330, the AnnexinV/7-AAD double staining was used to analyse cell apoptosis and the Western blot was used to detect the expression level of caspase-3. The results showed that AZD8330 could significantly inhibit the cell viability of IM9 and NCI-H929 cell lines in a time-and dose-dependent manner, the IC50 value (48 h) of IM9 and NCI-H929 were 19.88 ± 2.7 nmol/L and 29.3 ± 2.03 nmol/L respectively, these two cell lines were arrested on G1 phase of cell cycle, the apoptosis cells increased along with enhancement of AZD8330 concentration, and the expression level of cleaved caspase-3 protein was up-regulated. It is concluded that AZD8330 can efficiently inhibit the proliferation of NCI-H929 and IM9 cell lines, and induce apoptosis, suggesting that the AZD8330 may be a potential chemotherapeutic candidate for multiple myeloma therapy.

Effect of BRD4 inhibitor GSK525762A on proliferation and apoptosis of KU812 leukemic cells and its mechanism / 中国实验血液学杂志

This study was purposed to investigate the effect of bromodomain-containing protein 4 (BRD4) inhibitor GSK525762A on the proliferation and apoptosis of chronic myeloid leukemia blast crisis KU812 cells and its mechanism. KU812 cells were treated with different concentrations of GSK525762A (100, 250, 500, 1 000, 2 500 and 5000 nmol/L) and the inhibitory effects of drug on KU812 cell proliferation after 48 and 72 hours were detected by using CCK-8 assay. KU812 cells were treated with 3 different concentrations of GSK525762A (1.0, 2.5 and 5 µmol/L) and the cell apoptosis after 72 hours were assayed by using flow cytometry. KU812 cells were treated with DMSO and 2.5 µmol/L GSK525762A, and the mRNA levels of C-MYC, BCL-2, CDK6, BCL-xL, BAK and BAX were determined by using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The results showed that GSK525762A could significantly inhibit the proliferation of KU812 cells and the inhibitory effect on KU812 cell proliferation was dependent on the dose-course and time-course of GSK525762A treatment. GSK525762A treatment could induce apoptosis of KU812 cells in a dose-dependent manner. After GSK525762A treatment, the mRNA levels of proliferation-promoting genes ( C-MYC and CDK6) and pro-survival genes ( BCL-2 and BCL-xL) decreased, while the transcription level of pro-apoptosis genes BAK and BAX increased, as compared to that of the control group. It is concluded that GSK525762A can inhibit the proliferation of KU812 cells and induce cell apoptosis possibly through depressing the transcription of C-MYC, BCL-2, CDK6 and BCL-xL gene, and down-regulating BAK and BAX transcription.

Administration of high dose dexamethasone impairs the function of thymus cells / 中国实验血液学杂志

This study was purposed to investigate the effects of high-dose dexamethasone on structure and function of thymic epithelial cells (TEC). Male C57BL/6 mice aged 6 to 8 weeks were used as experimental animals. The mice were injected intraperitoneally with dexamethasone (20 mg/kg), and the other mice treated with saline were used as controls. Thymus was harvested at day 5 after treatment. The histological changes of the treated thymus were monitored by HE staining and in situ immunofluorescence staining. The ratio of each subset in the thymus were analyzed by using flow cytometry, and quantitative PCR was applied to detect the expression levels of IL-22 and Foxn1, which represent the regenerative function of thymus. The results showed that compared with control mice, the structure of TEC in mice treated with high-dose dexamethasone was damaged and the thymic cell number was declined dramatically (P < 0.05); the ratios of thymus cell subsets were changed, the number of double positive (DP) thymus cells among these subsets declined sharply (P < 0.05); the expression levels of Foxn1 and IL-22 increased by 34 and 8 folds respectively. It is concluded that the use of high-dose dexamethasone can lead to damage of the structure and function of TEC, and induce up-regulation of the expression of genes related to thymus repair.