Expression and Clinical Significance of Exosome Component 4 in Newly Diagnosed Patients with Diffuse Large B-Cell Lymphoma / 中国实验血液学杂志

OBJECTIVE@#To explore the expression of Exosome Component 4（EXOSC4） in the tissues of newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) and its clinical significance.@*METHODS@#The expression of EXOSC4 protein in the tissues of 181 newly diagnosed DLBCL patients was analyzed by immunohistochemical staining. Clinical data were collected. The correlation between EXOSC4 protein expression in the tissues of newly diagnosed DLBCL patients and clinical features were analyzed and its prognostic significance.@*RESULTS@#The positive rate of EXOSC4 protein expression was 68.51% in the tissues of 181 newly diagnosed DLBCL patients. These patients were divided into two groups, with 44 cases in high expression group and 137 cases in low expression group. There were no significant differences in age, gender, B symptoms, serum lactate dehydrogenase (LDH) level, Eastern Cooperative Oncology Group (ECOG) score, Ann Arbor stage, extranodal disease, International Prognostic Index (IPI) score, National Comprehensive Cancer Network IPI (NCCN-IPI) score, and cell origin between the two groups (P>0.05). Cox multivariate regression analysis showed that high EXOSC4 protein expression in tissues was an independent poor prognostic factor for OS and PFS in newly diagnosed DLBCL patients (all P<0.05). K-M survival analysis showed that newly diagnosed DLBCL patients with high EXOSC4 protein expression had significantly shorter overall survival (OS) and progression free survival (PFS) than those patients with low EXOSC4 protein expression (all P<0.05).@*CONCLUSION@#High EXOSC4 protein expression in tissues of newly diagnosed DLBCL patients is an independent poor prognostic factor for survival.

Research Advances on Abnormal Secretion and Function Abnormality of Exosomes Derived from Lymphoma Cells Caused by Latent EB Virus--Review / 中国实验血液学杂志

Abstract　　The Latent infection cansed by Epstein-Barr virus (EBV) closely relates with the occurrence and development of several kinds of lymphoma. Exosome (EXO) is functional bilayer membrane structural corpuscles which are secreted by cells contain proteins, lipids and nucleic acids. In recent years, researches showed that EXO play an important role in the occurrence and development of tumors. Therefore, the resenrches which compare the differences in quantity and contents of EXO secreted by cells between EBV negative lymphoma and EBV positive lymphoma and the clarify the influence of EXO on biological behaviors of lymphoma cells and immune cells have the important, significance for understanding the mechanisms related with effect of latent EBV on the occurrence and development of lymphoma by exosome pathway. This review focuses on research progress about the effect of latent EBV on amounts, contents and functions of EXO secreted by lymphoma cells.

Arginase Level in Apheresis Leukocyte-Reduced Platelets Stored for Different Time / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect of storage time on arginase level and possible source of arginase in apheresis leukocyte-reduced platelets(ALR-Plt).</p><p><b>METHODS</b>The arginase level and myeloperoxidase(MPO) levels in ALR-Plt and control plasma were detected by ELISA. The relationship between arginase level and MPO level in ALR-Plt was analyzed by correlation analysis.</p><p><b>RESULTS</b>There was no significant difference of arginase level between ALR-Plt stored less than 3 days and control plasma. However, arginase level in ALR-Plt stored over 3 days was significantly higher than that in ALR-Plt stored less than 3 days and control plasma(P<0.05). There was no significant difference of MPO level in ALR-Plt stored for different times, but the MPO level in ALR-Plt stored for different time was lower than that in control plasma. Correlation analysis showed that arginase level positively correlated with MPO level in ALR-Plt of different storage time (r=0.58).</p><p><b>CONCLUSION</b>The arginase level in ALR-Plt stored over 3 days increase significantly. The main possible source of arginase in ALR-Plt is the residual white blood cells, especially neutrophils.</p>

Growth Inhibition of Multiple Myeloma Cells Caused by MicroRNA-15a and Its Mechanisms / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect and possible mechanisms of miR-15a on growth of multiple myeloma(MM) cells.</p><p><b>METHODS</b>MM cell lines (U266 and RPMI8226) were transfected by lentiviral particles. MM stable cell lines were selected and collected by flow cytometry (FCM). Proliferation of MM cells before and after miR-15a high expression was detected by CCK-8 method. Apoptosis of MM cells before and after miR-15a high expression was detected by AO/EB dying, Hoechst 33258 dying and FCM, respectively. Cell cycle of MM cells before and after miR-15a high expression was detected by FCM. The expressions of miR-15a, BMI-1 and BCL-2 mRNA of MM cells before and after miR-15a high expression were detected by real-time PCR. The expressions of BMI-1 protein of MM cells before and after miR-15a high expression were detected by Western blot.</p><p><b>RESULTS</b>MM stable cell lines with miR-15a high expression was acquired. CCK-8 result showed that high expression of miR-15a could inhibit growth of MM cells (U266 and RPMI8226). AO/EB dying, Hoechst 33258 dying and FCM testing results showed that high expression of miR-15a could significantly induce apoptosis of MM cells (U266 and RPMI8226). The apoptosis rates of U266 and RPMI8226 cells in high expression group and control group were 90.52% vs 37.08% and 59.40% vs 44.17%, respectively. Meanwhile, FCM testing results showed that high expression of miR-15a could induce G1 arrest of MM cells (U266 and RPMI8226), which proportion of G1 phase were 41.50%±0.64%, 45.31%±0.77%, respectively. Real-time PCR results showed that during the growth inhibition process of MM cells caused by miR-15a high expression, the expression of BCL-2 mRNA decreased, but there was no significant changes in the expression of BMI-1 mRNA, while the expression of BMI-1 protein decreased significantly.</p><p><b>CONCLUSION</b>High expression of miR-15a can induce cell cycle arrest and apoptosis of MM cells, then inhibit their growth. The mechanisms may be related with the negative regulation of BMI-1 and BCL-2 genes in post-transcription level caused by miR-15a.</p>

Expression and Clinical Significance of Bmi-1 and P14 in Extranodal NK/T-cell Lymphoma / 中国实验血液学杂志

<p><b>OBJECTIVE</b>This study was aimed to investigate the expression and clinical significance of Bmi-1 and P14 in extranodal NK/T-cell lymphoma (ENKTCL) tissue.</p><p><b>METHODS</b>Maxvision immunohistochemistry technique was used to detect the expression level of Bmi-1 and P14 in the tissues of 21 patients with ENKTCL and 11 normal lymph nodes. The correlation of Bmi-1 or P14 expression with the clinical features and the correlation between Bmi-1 and P14 expression were analyzed.</p><p><b>RESULTS</b>The expression of Bmi-1 protein was higher in tissues of ENKTCL than that in tissues of lymph nodes, and the Bmi-1 expression levels did not correlate with patients' sex, age, lactate dehydrogenase (LDH), International Prognostic Index (IPI) scores and B symptoms (P > 0.05), except for clinical stage (P < 0.05). The P14 protein expression level was lower in ENKTCL tissues than in normal lymph node tissues, which did not correlate with age, sex, LDH, IPI scores, clinical stage and B symptoms. Correlation test showed a negative correlation between Bmi-1 and P14 (r = -0.472, P = 0.031).</p><p><b>CONCLUSION</b>Bmi-1 protein over-expresses in ENKTCL tissues that may display a negative-regulation effect on P14 in the genesis and progress of ENKTCL.</p>

Arginase Level in Suspended Red Blood Cells Storaged for Different Time / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect of storage time on arginase level, and the possible source of arginase in suspended red blood cells (RBC).</p><p><b>METHODS</b>The arginase and myeloperoxidase (MPO) levels in suspended RBC and control plasma were detected by ELISA. The free hemoglobin level in suspended RBC and control plasma were detected by colorimetric method. The relationship between arginase level, MPO level and free hemoglobin level in suspended RBC was analyzed by the related methods.</p><p><b>RESULTS</b>The arginase and free hemoglobin levels in suspended RBC were higher than those in control plasma. Otherwise, MPO level was not significantly different between suspended RBC and control plasma. All of them did not increase along with prolonging of storage time. There was not a significant correlation between arginase level and free hemoglobin level in suspended RBC of different storage time (r = 0.03), but arginase level positively correlated with MPO level in the suspended RBC of different storage time (r = 0.76).</p><p><b>CONCLUSION</b>The arginase level in suspended RBC storaged for different time increases significantly, but not along with prolonging of storage time. The main possible source of arginase in the suspended RBC is the residual white blood cell, especially neutrophils.</p>

Comparison of stroke volume variation with pulse pressure variation as a diagnostic indicator of fluid responsiveness in mechanically ventilated critically ill patients

To compare the diagnostic accuracy of stroke volume variation [SVV] and pulse pressure variation [PPV] in studies that examined both parameters in the same patient population. Literature search was conducted in PubMed, EMBASE, CINAHL, and Google Scholar. Receiver operator characteristic [ROC] curves were examined, and summary ROC curves were plotted. The study was conducted from January to July 2013 in The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China. The meta-analysis of 19 studies published during the years 2005 and 2013 revealed a high degree of diagnostic accuracy of both SVV and PPV in predicting fluid responsiveness. The sensitivity and specificity of both the parameters were observed above 80% in a heterogeneous group of over 850 patients of which 55% responded to fluid challenge. The following values along with 95% confidence interval were noticed: SVV - sensitivity 82 [59-93%] and specificity 84 [62-95%], PPV - sensitivity 84 [62-95%] and specificity 83 [58-94%]. Area under the curve values obtained in the pooled analysis were 0.84 [0.79-0.89] for SVV, and 0.88 [0.84-0.92] for PPV. Both SVV and PPV exhibit a high degree of diagnostic accuracy in predicting the success or failure of a fluid challenge in hemodynamically unstable critically ill patients under controlled mechanical ventilation

Analysis of the efficiency and influence factors of PBSC collection with AutoPBSC and MNC procedure of cell separator / 中国实验血液学杂志

This study was aimed to analyze the efficiency and influence factors of PBSC collection by an automatic (AutoPBSC procedure) and a semiautomatic apheresis procedure ( MNC procedure) of COBE Spectra cell separators. According to the different objects, A total of 109 apheresis cases were divided into autologous cohort (patient) and allogeneic cohort (donor). The quantity and quality of the collections and the characteristics of apheresis procedure were compared, the yields and influence factors of two cohorts with two kinds of procedures were analyzed respectively. The results showed that the collections of two procedure in patients and donors which processed the similar blood volumes were insignificantly different in MNC%, CD34⁺ %, CD34⁺ cell counts and Hb concentration (P > 0.05) ; the collections by AutoPBSC procedure had got fewer platelets, less product volumes whereas more ACD-A used, longer apheresis time in comparison with MNC procedure (P < 0.05). Correlation analysis indicated that MNC (r = 0.314,P = 0.015) , CD34⁺ cell counts (r = 0.922, P = 0.000) in collections were positively correlated with preahperesis in the autologus cohort by two procedures, CD34⁺ cell counts were correlated with WBC (r = 0.369, P = 0.004) and MNC (r = 0.495,P = 0.000) in collections; MNC (r = 0.896, P = 0.000) was positive correlated with preahperesis by AutoPBSC procedures and CD34⁺ cell counts also (r = 0.666,P = 0.000) by MNC procedure in the allogeneic cohort. Male had got more MNC and CD34⁺ cell counts than female (P < 0.05), age ≤ 40 had got more MNC and CD34⁺ cell counts than age>40 (P < 0.05) in patients by AutoPBSC procedure; age > 40 had got more CD34⁺ cell counts than age ≤ 40 by MNC procedure(P < 0.05). Only male had got more MNC and CD34⁺ cell counts than female (P < 0.05) by MNC procedure in donors. It is concluded that with same amount of blood processing, the PBSC collections from autologous patients and allogeneic donors had got a high degree of uniformly in purity of MNC and purity and concentration of CD34(+) cell counts by two procedure, whereas sex and age imposed more influence on PBSC collection in autologous.

MicroRNA-193b expression in newly diagnosed leukemia patients and its significance / 中国实验血液学杂志

This study was aimed to quantitatively detect the levels of microRNA-193b (miR-193b) in leukemia patients and explore its significance. Real time fluorescent quantitative PCR was used to detect the relative expression level of miR-193b. The expression changes of miR-193b in various types of leukemia were analyzed. Then the relationship among miR-193b expression, parts of laboratory index and the response to chemotherapy was analyzed as well. The results showed that miR-193b expression level in acute promyelocytic leukemia (APL) and chronic myeloid leukemia (CML) patients was not lower than that in normal group (P > 0.05). Except for APL, miR-193b expression level in acute myeloid leukemia (AML) patients was lower than that in normal group (P < 0.05). In AML (except for APL) patients, there was no correlation between white blood cell count (P > 0.05), the expression of CD34 (P > 0.05) and miR-193b expression level, but there was negative correlation between chemotherapy response and miR-193b expression level (P < 0.05). It is concluded that miR-193b expression level may be correlated with susceptibility of cells to chemotherapy in AML (except for APL) patients. miR-193b maybe become a new target in AML (except for APL) therapy.

Expression of MCL-1 and microRNA-29a in extranodal NK/T-cell lymphoma tissue / 中国实验血液学杂志

This study was aimed to explore the expression level and correlation of MCL-1 and miR-29a in extranodal NK/T-cell lymphoma (ENKTCL) tissue. Maxvision immunohistochemistry technique and real time fluorescent quantitative PCR were used to detect the expression level of MCL-1 and miR-29a in tissue of 20 patients with ENKTCL and 10 patients with proliferative lymphadenitis, respectively. The results showed that the expression of MCL-1 protein were higher in patients with ENKTCL than that in patients with proliferative lymphadenitis, but there were no significant correlation between MCL-1 overexpression and age, sex, Ann Arbor stage and International Prognostic Index (IPI), respectively. Correlation analysis indicated that there was significant negative correlation between miR-29a expression and MCL-1 expression (r = -0.59, P = 0.016). It is concluded that miR-29a may target MCL-1 gene, regulate its expression, then participate in tumorigenesis and development of ENKTCL.

Mechanism associated to enhancing the sensitivity of myeloma cells U266 to bortezomib by 2-methoxyestradiol / 中国实验血液学杂志

This study was aimed to explore the synergistic effect of 2-methoxyestradiol (2-ME2) and bortezomib (Bor) on the proliferative inhibition and apoptosis of U266 cell line and its possible mechanism. The cells were treated with 2-ME2, Bor alone and 2-ME2 combined with Bor, respectively. The cell viability and proliferative curve were detected by CCK8, the cell apoptosis was detected by caspase 3/7 activity test, cell cycle status was analyzed by flow cytometry, and real-time PCR was used to detect the mRNA expression of P21, BAX and BCL-2. The results showed that compared with cells treated with 2-ME2 or Bor alone, the proliferative potential of cells in combination group was significantly inhibited (p < 0.05), and apoptosis rate markedly increased (p < 0.05), cell cycle was arrested at G(1)-S phase, the mRNA expressive level of P21 and BAX increased, while the expression of BCL-2 decreased. It is concluded that 2-ME2 combined with Bor synergistically inhibits cell proliferation and induces apoptosis in U266 cell line. The possible mechanism may be associated with its effect of up-regulating P21 and BAX expressions.

april mRNA expression in newly diagnosed leukemia patients / 中国实验血液学杂志

This study was aimed to quantitatively detect the levels of april mRNA expression in leukemia patients so as to provide theoretical basis for the target therapy directing at april in leukemia. Real time fluorescent quantitative PCR was used to detect the relative expression level of april mRNA in newly diagnosed leukemia patients and to analyze the changes of its expression level in various type of leukemia. The results showed that the april mRNA expression level in acute leukemia (AL) patients was significantly higher than that in normal controls, there was statistical difference between them (p < 0.05); april mRNA expression level in acute myeloid leukemia (AML) patients was significantly higher than that in normal controls (p < 0.05) and positively correlated with white blood cell count ≥ 20.0 × 10(9)/L (p < 0.05), but not related with extramedullary infiltration and the expression of CD34. Except for acute promyelocytic leukemia (APL), april mRNA expression level was negatively correlated with sensitivity of patients to chemotherapy. april mRNA expression levels in acute lymphoid leukemia (ALL) and chronic myeloid leukemia (CML) patients were not higher than that in normal controls, there was no statistical difference between them (p > 0.05). It is concluded that april gene overexpression exits in AML patients. APRIL protein produced by AML cells probably plays an important role in abnormal proliferation and drug-resistance of AML cells.

Lysophosphatidic acid acyltransferase β gene expression in newly diagnosed leukemia patients / 中国实验血液学杂志

This study was aimed to quantitatively detect the expression level of lysophosphatide acid acyltransferase β (lpaat β) mRNA in leukemia patients so as to provide theoretical basis for the target therapy of lpaat β in leukemia. Real-time fluorescently quantitative PCR was used to detect the relative expression level of lpaat β mRNA to analyze its expression change in various type of leukemia. The results showed that the lpaat β mRNA expression level in acute leukemia (AL) patients was significantly higher than that in normal controls (p < 0.05); lpaat β mRNA expression level in acute myeloid leukemia (AML) patients was significantly higher than that in normal controls (p < 0.05) and was positively correlated with white blood cell count (≥ 20.0 × 10(9)/L) (p < 0.05) and CD34 expression level of leukemia, but was not related with extramedullary infiltration. Except for acute promyelocytic leukemia (APL), the lpaat β mRNA expression level was negatively correlated with chemotherapy sensitivity in chronic myeloid leukemia (AML) patients. lpaat β mRNA expression level in chronic myeloid leukemia (CML) patients was significantly higher than that in normal controls (p < 0.05). lpaat β mRNA expression level in acute lymphoid leukemia (ALL) patients was not higher than that in normal controls (p > 0.05). It is concluded that the lpaat β gene overexpression exists in both AML and CML patients. lpaat β produced by AML cells probably plays an important role in abnormal proliferation and drug-resistance of AML cells.

Gfi-1 expression in leukemia patients and inhibitory effects of lentiviral vector mediated silence of Gfi-1 gene on proliferation in K562 cells / 中国实验血液学杂志

This study was aimed to quantitatively detect the expression levels of gfi-1 gene in leukemia patients, and to investigate the effect of gfi-1 gene silenced by short hairpin RNA (shRNA) on proliferation of leukemia cell line K562. Quantitative real-time PCR and Western blot were used to detect the mRNA and protein expression levels of GFI-1 in newly diagnosed patients with leukemia. One pair of oligonucleotide sequences targeted at human gfi-1 mRNA were designed and synthesized. The annealed oligonucleotide fragments were subcloned into pLVTHM vector. Virus particles were collected when the control and shRNA vectors had been co-transfected with the psPAX2 packaging plasmid and the envelope plasmid pMD2 G into HEK-293T cells using Lipofectamine 2000. The K562 cells were transfused with 1 x 10⁶ recombinant lentivirus-transfusing units plus 6 microg/ml of polybrene. Rea-time PCR and Western blot were used to detect the expressions of gfi-1 and bax mRNA after lentivirus transfusion. CCK-8 assays was used to evaluate the proliferation potential of cells. The results showed that the gfi-1 expression level in all leukemia patients was significantly higher than that in normal group (p < 0.05); the gfi-1 mRNA expression in chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) or acute lymphoid leukemia (ALL) patients was significantly higher than that in normal group (p < 0.05); but the difference of gfi-1 mRNA expression between AL and CML or ALL and AML was not significant. Notably, the gfi-1 mRNA expression level had a positive correlation with high white blood cell count of > 20.0 x 10⁹/L (p < 0.05). As was expected, the mRNA and protein level of gfi-1 was reduced significantly in K562 cells after lentivirus transfusion, whereas the mRNA and protein level of bax was upregulated. And CCK-8 assay showed that gfi-1 gene silencing can inhibit K562 proliferation. It is concluded that gfi-1 expression is upregulated in leukemia patients and may contribute to leukemogenesis. The gfi-1 specific shRNA mediated by lentivirus can effectively down-regulate the expression of gfi-1 and inhibit the proliferation of K562 cells, which lay a basis for further research on gene therapy in leukemia.

Effect of bortezomib on lymphoma cell line CA46 and its relative mechanisms / 中国实验血液学杂志

The objective of this study was to explore the effect of bortezomib (BZM) on lymphoma cell line CA46 and its relative mechanisms in vitro. The effects of BZM on the proliferation and apoptosis of CA46 cells were assayed by MTT method and flow cytometry respectively. The effect of BZM on the expression levels of procaspase-3 and BCL-2 protein were detected by Western blot. The results indicated that the BZM could inhibit the growth of CA46 cells significantly and the concentration of 50% growth inhibition (IC₅₀) at 24 and 48 hours were 53.19 and 19.68 nmol/L respectively. After treatment with 20, 40, 80 nmol/L BZM for 24, 48 and 72 hours, a dose- and time-dependent apoptosis of CA46 cells could be observed. After treatment with 20 nmol/L BZM at different time point, a time-dependent reduction of procaspase-3 and BCL-2 protein expression in CA46 cells was found. It is concluded that the BZM can inhibit the proliferation and induce the apoptosis of CA46 cells, which relative mechanism may involve the reduction of BCL-2 and the activation of caspase 3.

Effect of bcl-2 siRNA on apoptosis of Burkitt's lymphoma cell line CA46 / 中国实验血液学杂志

The aim of this study was to investigate the effect of bcl-2 siRNA on bcl-2 gene expression and apoptosis of lymphoma cell line CA46. A siRNA was designed and synthesized. Then siRNA was transfected into CA46 cells by cationic liposome. At 48 hours after transfection, apoptosis and mitochondria transmembrane potential of CA46 cells were detected by flow cytometry, the expression of bcl-2 mRNA and BCL-2 protein in CA46 cells were detected by RT-PCR and flow cytometry respectively. The results showed that at 48 hours after transfection, apoptosis of CA46 cells occurred, mitochondria transmembrane potential changed. The expression of bcl-2 mRNA and BCL-2 protein in CA46 cells decreased significantly. In conclusion, bcl-2 siRNA depresses the expression of bcl-2 gene in CA46 cells specifically, then changes the mitochondria transmembrane potential, resulting in apoptosis of CA46 cells.

Mechanism underlying 2-methoxyestradiol inducing apoptosis of K562 cells / 中国实验血液学杂志

The aim of this study was to investigate apoptotic effect of 2-methoxyestradiol (2-ME2) on K562 cells and its mechanism. K562 cells were treated with different concentrations of 2-ME2. MTT assay was used to examine the effect inducing growth inhibition. DNA fragmentation assay and Annexin V-FITC/PI staining were used to detect the effect of apoptosis. The change of mitochondrial transmembrane potential was analyzed by flow cytometry. The expressions of related gene mRNA and/or proteins were detected by RT-PCR and Western blot respectively. The results indicated that the 2-ME2 inhibited proliferation of K562 cells in a time- and dose-dependent manners and the concentration of 50% growth inhibition (IC(50)) was 2 micromol/L at 48 hours. 2-ME2 induced DNA ladder and significantly increased apoptosis in K562 cells when exposed to 2 micromol/L of 2-ME2 for 24, 48 and 72 hours, the result of Annexin-V/PI staining showed that rates of the apoptotic cells were 13.78%, 22.32% and 29.43% respectively, which was remarkably higher than that of control (1.78%) (p < 0.05). The FCM analysis showed that the mitochondrial transmembrane potential in K562 cells lowered after exposed to 1, 2 and 4 micromol/L of 2-ME2 for 24 hours. 2-ME2 down-regulated the expression of bcr/abl and bcl-2, up-regulated the expression of bax mRNA, and down-regulated protein expressions of bcl-2, procaspase-3, procaspase-9, PARP (116 kD) and p-Akt, and up-regulated expression of cytoplasmic Cyto-C and PARP 85 kD apoptosis-related cleavage fragment protein, but had no effect on total Akt protein in K562 cells after treated with 2 micromol/L of 2-ME2 for 24, 48 and 72 hours. It is concluded that the 2-ME2 can induce the apoptosis and inhibit the proliferation of K562 cells by increasing the ratio of bax/bcl-2, reducing the mitochondrial transmembrane potential, releasing cytochrome C to cytoplasm, initiating the mitochondrial apoptosis pathway and leading in turn to caspase-3 activation. These findings suggest that interfere PI3K/Akt signal pathway via down-regulating the expression of bcr/abl mRNA is implicated in the effect of 2-ME2 on K562 cells.

Relationship between lysophosphatide acid acyltransferase beta and tumor - review / 中国实验血液学杂志

Phosphatide acid (PA) is a kind of multifunctional bioactive phospholipid. It has been proved that PA produced by lysophosphatide acid acyltransferase (LPAATbeta) was involved in several signalling pathways in tumor cells, leading to the proliferation, apoptosis, migration, invasion, respiratory burst, expression and release of cytokine form tumor cells. The fact that expression of LPAATbeta was higher in tumor tissues than in their homologous normal tissues, and that antitumor effect of inhibitng LPAATbeta on solid tumor and hematological malignancy suggested that the targeting LPAATbeta would be a promising method of antitumor treatment. In this paper, the relevant basic and preclinical researches of LPAATbeta on antitumor treatment were summarized.

Effect of VEGF antisense RNA on inducing apoptosis of myeloma cells and inhibition of angiogenesis in endothelial cells in vitro / 中国实验血液学杂志

This study was aimed to investigate the effect of VEGF antisense RNA on proliferation and apoptosis in myeloma cell line U266 as well as on angiogenesis in endothelial cell ECV304, and to explore the feasibility of gene therapy for multiple myeloma using VEGF antisense RNA. The VEGF121 cDNA was inserted into multiple clone site of eukaryotic expression vector pIRES2-EGFP to construct the recombinant plasmid AS-VEGF. Restriction endonuclease analysis and DNA sequencing were used to confirm the reverse orientation of the VEGF cDNA. The recombinant plasmid was transfected into human myeloma cell line U266 and the positive clone was screened by G418. The VEGF mRNA and protein expressions of the positive clone were detected by RT-PCR and Western blot respectively. The viability and apoptosis of U266 cells were observed by MTT assay, flow cytometry. Angiogenesis was tested by network formation of endothelial cells on matrigel. The results indicated that the recombinant plasmid AS-VEGF expressing VEGF antisense RNA were constructed successfully. VEGF expression in U266 cells was blocked partially by VEGF antisense RNA. Expression of VEGF mRNA and protein decreased more significantly in U266 cells transfected by AS-VEGF than that in control group. Then increasing of apoptosis and inhibition of proliferation in U266 cells transfected by AS-VEGF were observed. Vasoformation on matrigel in the supernatants of U266 culture group transfected by AS-VEGF decreased more significantly than that in control group. It is concluded that VEGF antisense RNA can inhibit the expression of VEGF gene in U266 cells, thereby inhibits the proliferation of U266 cells; increases the apoptosis of U266 cells; and inhibits angiogenesis in vitro.

Mechanisms underlying the effect of arsenic trioxide on proliferation inhibition and apoptosis induction in myeloma cell line u266 / 中国实验血液学杂志

The aim of this study was to explore the mechanisms underlying effect of arsenic trioxide (As2O3) on myeloma cell line U266 in vitro. The viability and apoptosis of U266 cells were observed by MTT assay, flow cytometry and DNA agarose gel electrophoresis. The expression of hTERT mRNA was assessed by RT-PCR analysis. The variation of procaspase-3, bcl-2 and hTERT protein expression were detected by Western blot. The results indicated that the As2O3 could inhibit the growth of U266 cells significantly and the concentration of 50% growth inhibition (IC50) was 2 micromol/L. After treatment with 2.5 micromol/L As2O3 at 24, 48 and 72 hours, a dose- and time-dependent apoptosis of U266 cells could be observed. After treating U266 cells with 2 micromol/L As2O3 at different time points, a time-dependent reduction of procaspase-3, hTERT mRNA and protein was found without any change of bcl-2 expression. It is concluded that the As2O3 can change the mitochondrial transmembrane potential, initiating the mitochondial apoptosis pathway, leading in turn to caspase-3 activation, and inducing the apoptosis of U266 cells. These findings suggest that the reduction of hTERT plays a critical role in the apoptosis of U266 cells induced by As2O3.