Significance of Peripheral Blood Lymphatic to Monocyte Ratio in the Progress of PGI-DLBCL / 中国实验血液学杂志

OBJECTIVE@#To explore the significance of lymphocyte to monocyte ratio (LMR) in the disease progress of primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL).@*METHODS@#The clinical data of 43 patients diagnosed as PGI-DLBCL in our hospital from January 2011 to December 2015 were collected, and the disease progress was followed up.@*RESULTS@#According to the ROC curve, the threshold value of LMR for 2 years PFS (%) of PGI-DLBCL patients was 2.6. Unvariate analysis showed that LMR (P＜0.05), large enclosed mass lesion (P＜0.01) and IPI (P＜0.05) were prognostic factors affecting PFS, the COX regression model multivariate analysis showed that LMR＜2.6 [ (risk ratio (RR)=3.083, 95%CI 1.828-8.313, P＜0.01], and large enclosed mass lesions (RR=2.718, 95%CI 1.339-6.424, P＜0.05) were the independent adverse prognostic factor for two years PFS.@*CONCLUSION@#Both LMR＜2.6 and large enclosed mass lesions relate with the progress of PGI-DLBCL.

Effect of OCT4A Gene on the Biological Characteristics of K562 Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To evaluate biological effects of OCT4A gene on K562 cells and explore the molecular mechanism of K562 cell apoptosis.</p><p><b>METHODS</b>Two recombinant lentiviral vectors were constructed, which could stablely up- regulate and down- regulate OCT4A protein. Recombinant lentivirus was generated by co-transfection of three-plasmids and transfec-ted into K562 cells. The experiments were divided into 5 groups: normal, pLVX-OCT4A-ZsGreen1, pLVX vector control, PLB-OCT4A shRNA and non-specific shRNA groups. Western blot was applied to detect the expression of OCT4A protein, the cell counting kit-8 was applied to evaluate the effect of OCT4A on proliferation of K562 cells. The apoptosis and differentiation of K562 cells were detected by flow cytometry with AnnexinV/7-AAD double staining. The mRNA expressions of caspase-3,BIM,BCL-xL,BAX in K562 cells were determined by real time PCR.</p><p><b>RESULTS</b>The OCT4A fragment was amplified by reverse transcription polymerase chain reaction(RT-PCR), the 2 lentiviral vectors were successfully constructed. In comparson with those in the control group, the expression of OCT4A protein of pLVX-OCT4A-ZsGreen1 group was significantly increased, but decreased in PLB-OCT4A shRNA group. CCK-8 assay showed that the higher the content of OCT4A protein, the faster the cell proliferation. The apoptosis rate was (3.48±0.52)% of pLVX-OCT4A-ZsGreen1 group, which was lower than that of control group, while the apoptosis rate PLB-OCT4A shRNA group was (7.25±0.57)%, which was higher than that of control group (P<0.05), however, the K562 cells differentiation was not influenced(P>0.05). Compared with control group, the gene expression of Caspase-3,BIM and BAX was down-regulated(P>0.05), but a significant up-regulation of BCL-xL gene expression was observed(P<0.05).</p><p><b>CONCLUSION</b>Two lentiviral vectors have been successfully constructed, which can stably up- and down- regulate the expression of OCT4A in K562 cells respectively. OCT4A can promote the K562 cell proliferation and inhibit the apoptosis, the mechanism may be related with up-regulation of BCL-xl expression.</p>

Establishment and Identification of Mouse Model of Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To establish a mouse model of Phacute lymphoblastic leukemia (ALL) for providing a valuable tool to facilitate the researches on PhALL.</p><p><b>METHODS</b>CML-like mice were generated by transfection to bone marrow cells of BABL/c with Mig190 retrovirus. The PhALL mouse model was established by infusion of sorted CML like mouse-derived BCR-ABLB cells into the mice of same linege. Immonophenotypes, BCR-ABL transcription and expression of these leukemic cells were detected by flow cytometry, RT-PCR and Western blot respectively.</p><p><b>RESULTS</b>CML-like presentation appeared in the mice after Mig190 virus transfection. After infusion with sorted BCR-ABLB cells, all the receipted mice eventually presented the clinical signs of acute leukemia. Flow cytometry analysis showed that these leukemic cells were positive for CD19; both RT-PCR and Western blot indicated that this mouse model is consistent with PhALL phenotypecally and molecalarlly.</p><p><b>CONCLUSION</b>A novel method to establish PhALL mouse model has been developed successfully, and this model can provide useful tool for the study of PhALL.</p>

Effect of Metformin on Proliferation, Differentiation and Apoptosis of THP-1 Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of metformin on proliferation, differentiation and apoptosis of THP-1 cells and explore its possible mechanism.</p><p><b>MEHODS</b>THP-1 cells were cultured with different concentrations of metformin for 24 h and 48 h. The cell proliferation was evaluated by CCK-8, the cell apoptosis was analyzed by Annexin V/7-AAD double labeling, the expression of CD14 and CD11b (surface differentiation antigens on THP-1 cells) was evaluated by flow cytometry, the BCL-XL, BAX, BIM and caspase-3 mRNA expressions of THP-1 cells were detected by real time quantitative PCR.</p><p><b>RESULTS</b>Metformin could significantly inhibit the growth of THP-1 cells in a time- and dose- dependent manner. After treated with 20 mmol/L metformin for 24 h, the expressions of CD14 and CD11b in THP-1 cells didn't change much (P>0.05), the early apoptosis rates in exprimental and control groups were (2.02±0.85)% and (4.46±1.33)% respectively, the late apoptosis rates in experimental and control groups were (1.43±0.83)% and (3.31±0.59)% respectively. In process of inducing effect of 20 mmol/L metformin on THP-1 cells, the expressions of BCL-XL and BIM did not significantly changed, while the expressions of BAX and caspase-3 significantly increased (P<0.01).</p><p><b>CONCLUSION</b>Metformin can effectively inhibit proliferation and induce apoptosis of THP-1 cells. However, it has no significant effect on differentiation of THP-1 cells, its mechanism inducing apoptosis maybe related with up-regulating BAX and caspase-3.</p>

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.

Establishment of a high efficient human coagulation factor VIII eukaryotic expression system using lentiviral vector / 中华血液学杂志

<p><b>OBJECTIVE</b>To establish a high efficient human coagulation factor VIII (FVIII) eukaryotic stable expression system using lentiviral vector, and determine its biosafety.</p><p><b>METHODS</b>Lentiviral transfer plasmid carrying human B-domain-deleted FVIII(BDDhFVIII)-IRES-GFP(BDDhFVIII/pXZ9)or IRES-GFP(pXZ9) was constructed. Lentivirus particles were produced by transiently co-transfected 3-plasmids into 293FT cells and further concentrated via ultracentrifugation. CHO cells were infected, 72h later, the FVIII antigen (FVIII:Ag) concentration in the medium was examined by ELISA, the activity was detected via one stage coagulation,and the transcription of FVIII in the infected CHO cells was determined by RT-PCR.Virus infection ability in the medium and the gag gene in CHO cells were determined to evaluate the model's biosafety.</p><p><b>RESULTS</b>Lentiviral transfer plasmid BDDhFVIII-IRES-GFP(BDDhFVIII/pXZ9)carrying human B-domain-deleted FVIII or IRES-GFP (pXZ9) was successfully constructed, and high titer lentiviruses has been prepared. The lentivirus could infect CHO cells efficiently, after an additional 72 h, the FVIII:Ag concentration had up to (1724.9±283.7) mU/ml, the FVIII:C level increased to (10.58±1.55)%, and transcripts of BDDhFVIII mRNA could be measured by RT-PCR. Neither the gag gene nor the virus in the supernatant was detected.</p><p><b>CONCLUSION</b>Lentivirus-mediated human coagulation factor VIII could be expressed efficiently in CHO cells. The system couldn't produce offspring virus, proving a good biosafety.</p>

Construction of shRNA expression vector targeting AATF and establishment of stably transfected U937 cells / 中国实验血液学杂志

This study was aimed to construct the targeting AATF shRNA eukaryotic expression vector and establish the stably transfected U937 cell lines. The sequence of AATF mRNA was obtained from GenBank. After excluding homology, three plasmid expression vectors coding shRNA targeting 228 ∼ 249, 303 ∼ 324 and 443 ∼ 464 of AATF gene sequence were synthesized. Two terminals of shRNA carried BamHI and HindIII restriction sites. The selected nucleotides were cloned into the plasmid pSilencer 3.1-H1 neo respectively, and the resultant recombinant plasmids were named as pSA-1, pSA-2, pSA-3. The sequences of the recombinant plasmids were identified by DNA sequencing. The recombinant plasmids were transfected into the cell line U937 by electroporation with Neon(TM) Transfection System. The transfected cells were persistently screened under G418 (500 mg/L), and isolated with a limited dilution for 8 weeks. The inhibition of AATF mRNA and protein expression was respectively detected by RT-PCR and Western blot. The results indicated that RNAi eukaryotic expression vectors targeting AATF had correct reading frame and nucleotide sequence. Real-time PCR revealed that AATF shRNA effectively silenced mRNA expression of AATF. Western blot analysis found that AATF shRNA obviously suppressed protein expression of AATF (P < 0.05). It is concluded that the shRNA eukaryotic expression vector has been successfully constructed which can inhibit the expression of AATF, and the establishment of stably transfected U937 cell lines provide a original route for exploring the mechanism of AATF in human Leukemia further.

Effect of VE-cadherin on sensitivity to Imatinib in Sup-B15 Philadelphia chromosome positive acute lymphoblastic leukemia cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the sensitivity of imatinib mesylate (IM) on Sup-B15 Ph⁺ acute lymphoblastic leukemia (ALL) cells knockdown of VE-cadherin (CD144), and to further explore its mechanism.</p><p><b>METHODS</b>CD144 in Sup-B15 leukemia cells was stably knock downed via lentivirus-mediated RNA interference (named as Sup-B15/shVEC). The inhibitory effects of IM on Sup-B15/shVEC and Sup-B15 leukemia cells were measured by CCK-8 test, and the apoptosis of those cells was determined by AnnexinV/7-AAD dyeing using flow cytometry, the percentage of CD34⁺CD38⁻ leukemia cells also by flow cytometry. ALDH1 mRNA levels were detected by real-time RT-PCR, and protein levels of CD144, CD133, Bcr-abl and β-catenin by Western blot.</p><p><b>RESULTS</b>IM treatment presented inhibitory effects on Sup-B15/shVEC and Sup-B15 leukemia cells at multiple concentrations of IM. The IC50 of IM on Sup-B15/shVEC and Sup-B15 leukemia cells were 25.1μmol/L and 18.7μmol/L, respectively (P<0.05). After 48h of 20 μmol/L IM treatment, the percentages of apoptosis cell in Sup-B15/shVEC cells and Sup-B15 cell were (13.52±2.06)% and (3.03±0.72) %, respectively (P<0.05). The percentage of CD34⁺CD38⁻ cells in Sup-B15 cells was significantly higher than in Sup-B15/shVEC cells [(2.39±0.28)% vs (0.96±0.07)%, P<0.05). As compared to Sup-B15 cells, the transcription of ALDH1 in Sup-B15/shVEC was remarkably downregulated, and the CD133 protein level was also downregulated in Sup-B15/shVEC cells. Both cytoplasmic and nucleic β-catenin protein levels (but not for Bcr-abl levels) decreased in Sup-B15/shVEC cells as compare to Sup-B15 cells.</p><p><b>CONCLUSION</b>Knockdown of CD144 sensitized Sup-B15 Ph+ ALL cells to IM. The possible mechanisms underlying this phenomenon might be via inhibiting β-catenin nucleic translocation and facilitating β-catenin degradation.</p>

Propagation of prdm1 gene knockout mouse and its genotype identification / 中国实验血液学杂志

This study was aimed to propagate and identify the prdm1 gene-knockout mice, so as to lay the foundation for studying Blimp-1 protein. Two kinds of transgenic homozygous mice with B6.prdm1(flox/flox) and B6.Lck-Cre were feed and propagated; after successful propagating, the first passage mice were obtained; after the first passage mice were copulated once again, the genotypes were obtained as follows: B6. prdm1(wild/wild). Lck-Cre, B6. prdm1(wild/wild), B6.prdm1(flox/flox). Lck-Cre, B6.prdm1(flox/wild). Lck-Cre, B6.prdm1(flox/flox), B6. prdm1(flox/wild). The genomic DNA of second passage mice was extracted, the Cre and loxp gene fragments were amplified by PCR, then the size of Cre and loxp genomic DNA were detected by agarose gel electrophoresis. The mice with B6.prdm1(flow/flox). Lek-Cre were used as conditionally prdm1-knockout mice, B6.prdm1(flox/wild). Lck-Cre mice, B6.prdm1(flox/flox) and B6 mice were used as controls. The spleen T lymphocytes and B lymphocytes were sorted by using magnetic beads, the blimp-1 target protein was identified by Western blot. The results showed that the two transgenic homozygous mice had the ability to reproduce, and the separation ratio of second passage mice generated from propagation of their offspring cach other meet Mendelian laws, and the prdm1 gene-knockout mice also could successfully obtained. It is concluded that the application of Cre-loxp system may successfully obtain plentiful prdm1 gene-knockout mice.