Current status of diagnosis and treatment of chronic lymphocytic leukemia in China: A national multicenter survey research / 中华血液学杂志

Objective: To understand the current status of diagnosis and treatment of chronic lymphocytic leukemia (CLL) /small lymphocytic lymphoma (SLL) among hematologists, oncologists, and lymphoma physicians from hospitals of different levels in China. Methods: This multicenter questionnaire survey was conducted from March 2021 to July 2021 and included 1,000 eligible physicians. A combination of face-to-face interviews and online questionnaire surveys was used. A standardized questionnaire regarding the composition of patients treated for CLL/SLL, disease diagnosis and prognosis evaluation, concomitant diseases, organ function evaluation, treatment selection, and Bruton tyrosine kinase (BTK) inhibitor was used. Results: ①The interviewed physicians stated that the proportion of male patients treated for CLL/SLL is higher than that of females, and the age is mainly concentrated in 61-70 years old. ②Most of the interviewed physicians conducted tests, such as bone marrow biopsies and immunohistochemistry, for patient diagnosis, in addition to the blood test. ③Only 13.7% of the interviewed physicians fully grasped the initial treatment indications recommended by the existing guidelines. ④In terms of cognition of high-risk prognostic factors, physicians' knowledge of unmutated immunoglobulin heavy-chain variable and 11q- is far inferior to that of TP53 mutation and complex karyotype, which are two high-risk prognostic factors, and only 17.1% of the interviewed physicians fully mastered CLL International Prognostic Index scoring system. ⑤Among the first-line treatment strategy, BTK inhibitors are used for different types of patients, and physicians have formed a certain understanding that BTK inhibitors should be preferentially used in patients with high-risk factors and elderly patients, but the actual use of BTK inhibitors in different types of patients is not high (31.6%-46.0%). ⑥BTK inhibitors at a reduced dose in actual clinical treatment were used by 69.0% of the physicians, and 66.8% of the physicians had interrupted the BTK inhibitor for >12 days in actual clinical treatment. The use of BTK inhibitors is reduced or interrupted mainly because of adverse reactions, such as atrial fibrillation, severe bone marrow suppression, hemorrhage, and pulmonary infection, as well as patients' payment capacity and effective disease progression control. ⑦Some differences were found in the perceptions and behaviors of hematologists and oncologists regarding the prognostic assessment of CLL/SLL, the choice of treatment options, the clinical use of BTK inhibitors, etc. Conclusion: At present, a gap remains between the diagnosis and treatment of CLL/SLL among Chinese physicians compared with the recommendations in the guidelines regarding the diagnostic criteria, treatment indications, prognosis assessment, accompanying disease assessment, treatment strategy selection, and rational BTK inhibitor use, especially the proportion of dose reduction or BTK inhibitor discontinuation due to high adverse events.

Expression of MiR-296-5p in Diffuse Large B-Cell Lymphoma and Its Influence on Biological Behavior of Tumor Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To detect the expression of miRNA-296-5p in diffuse large B cell lymphoma (DLBCL) cells and study the proliferation, migration and apoptosis of DLBCL cells after interfering the expression of miRNA-296-5p.</p><p><b>METHODS</b>The expression of miRNA-296-5p in DLBCL cells line DB cells was detected by real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The possible roles of miRNA-296-5p in the biological and behavioral properties of DLBCL-DB cells were explored by transfection of miRNA-296-5p inhibitor for miRNA-296-5p knockdown, and detected by using CCK-8 method, Transwell method and Annexin V-FITC/PI.</p><p><b>RESULTS</b>miRNA-296-5p was highly expressed in DLBCL-DB cells, and the inhibition of miRNA-296-5p could induce suppression of cell proliferation and migration, but the cell apoptosis was not changed significantly.</p><p><b>CONCLUSION</b>The high expression of miRNA-296-5p may relate with the occurence and development of DLBCL, which may be a new therapeutic target for DLBCL.</p>

Expression and Clinical Prognostical Significance of RIP2 in Diffuse Large B Cell Lymphoma / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression and prognosis significance of receptor interacting protein 2 (RIP2) in diffuse large B-cell lymphoma (DLBCL).</p><p><b>METHODS</b>The expression of RIP2 in DLBCL GCB and non-GCB type was detected by immunohistochemistry, at same time the expressions of BCL-2 and C-MYC were detected. Then, the role of RIP2 in development of DLBCL was analyzed by related clinical and pathological parameters.</p><p><b>RESULTS</b>The expression of RIP2 was related with middle-high risk group by IPI score, the An Arbor stage III+IV and intranodal lesions, and the differences were statistically significant (P<0.05). Besides, the single factor survival analysis suggested that GCB-type DLBCL showed a higher survival rate than that in non-GCB type(P<0.05). Patients with RIP2showed a lower survival rate as compared with patients with PIP2(P<0.05), among which the patients receiving R-CHOP had a higher survival rate than that of those receiving CHOP (P<0.01). The expression of RIP2 in DLBCL cell lines was higher than that in peripheral mononuclear cells of normal subjects (P<0.01) and expressed differently in DLBCL of GCB and non-GCB type (P<0.01).</p><p><b>CONCLUSION</b>The expression of RIP2 may relate with the poor prognosis and specific subtype of DLBCL.</p>

Distribution of Pathogenic Bacteria and Its Influence on Expression of BCL-2 and BAX Protein after HSCT in the Patients with Hematological Malignancies / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the distribution of pathogenic bacteria in the patients with hematologic malignancies received hematopoietic stem cell transplantation (HSCT) and its influence on the expression of BCL-2 and BAX proteins.</p><p><b>METHODS</b>The clinical data of 64 patients with malignant lymphoma (ML) received auto-HSCT from January 2011 to December 2015 in our hospital were analyzed. On basis of post-treansplant infection, the patients were divided into infection group (36 cases) and non-infection group (28 cases). The distribution of pathogenic bacteria in 2 groups was identified, the T lymphocyte subsets of peripheral blood, expression level of apoptotic proteins and C-reaction protein (CRP) in 2 group were detected.</p><p><b>RESULTS</b>Thirty-six strains of pathogenic bacteria were isolated from 36 case of hematological malignancy after HSCT, including 24 strains of Gram-negative bacteria (66.67%) with predominamce of klebsiella pneumoniae (19.44%). The periperal blood CD4+ (t=2.637, P<0.01), CD4+/CD8+ ratio (t=8.223, P<0.01), BCL-2 protein (t=5.852, P<0.05), BCL-2/BAX ratio (t=14.56, P<0.01) in infection group were significantly lower than those in non-infection group, while CD8+ (t=2.285, P=<0.01), CRP (t=39.71, P<0.01), BAX level in infection group were higher than those in non-infection group. The pearson correcation analysis showed that the CD4+/CD8+ ratio in infection group positively correlated with BCL-2/BAX ratio (t=0.341, P<0.05), while serum CRP level in infection group negatively correlated with BCL-2/BAX ratio (t=-0.362, P<0.05).</p><p><b>CONCLUSION</b>The pathogenic bacteria infecting ML patients after HSCT were mainly Gram-negative bacteria. The post-transplant infection can promote the expression up-regulation of related inflammatory factors and apoptotic proteins. The pathogens may be involved in cell apoptisis that provides a new strategy to treat the hematologic malignancies.</p>

Expression and Clinical Pathological Significance of EBER, PTEN and VEGF in Angioimmunoblastic T-Cell Lymphoma / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression and clinical pathological significance of EB virus (Epstein-Barr virus, EBV), PTEN and VEGF in angioimmunoblastic T -cell lymphoma (AITL).</p><p><b>METHODS</b>The EBV -encoded small RNA (EBER) expression in 21 cases of AITL was detected by in situ hybridization. The expressions of PTEN and VEGF were detected in 21 cases of AITL and 20 cases of lymph node reactive hyperplasia by immunohistochemical EnVision two-steps method. The expression and clinicopathological significance of EBV, PTEN and VEGF in AITL were analyzed.</p><p><b>RESULTS</b>The positive expression rate of EBER in 21 cases of AITL was 61.9%; the expressions of PTEN and VEGF in AITL and lymph node reactive hyperplasia were significantly different (P<0.05). The expressions of EBER and PTEN negatively correlated (P<0.05). The EBER positive expression rates of male patients in AITL group and the progressed group was 80% and 78.6% respectively, which were significantly higher than that in female patients and patients in non- advanced group (P<0.05); the PTEN expression rates in the AITL group accompanying B symptoms and progressed group were 31.3% and 21.4%, respectively, which were significantly lower than those in patients without B symptoms and non-progressed group (P<0.05). Survival analysis showed that the PTEN expression negatively correlated with the overall survival rate of patients (P<0.05).</p><p><b>CONCLUSION</b>EBV infection and low expression of PTEN may indicate the deterioration of angioimmunoblastic T-cell lymphoma. Whether the EBV involved in the ocurring of T-cell angioimmunoblastic lymphoma by down-regulating PTEN expression is unclear, further research is needed.</p>

Significance of regulatory B cells in nosogenesis of immune thrombocytopenia / 中国实验血液学杂志

This study was aimed to investigate the role of regulatory B cells (Breg) in pathogenesis of immune thrombocytopenia (ITP) and its clinical significance. A total of 35 ITP patients and 20 normal controls were enrolled in this study. The expression of CD19(+)CD24(hi)CD38(hi) B cells was detected by flow cytometry and the expression of IL-10 mRNA and TGF-β1 mRNA was assayed by RT-PCR. The results indicated that the expression level of CD19(+)CD24(hi)CD38(hi) B cells in peripheral blood of newly diagnosed ITP patients was obviously lower than that in normal controls (P < 0.05); the expression level of CD19(+)CD24(hi)CD38(hi) B cells in ITP patients with increased platelet count after treatment was higher than that before treatment (P < 0.05); the expression level of IL-10 mRNA in newly diagnosed ITP patients was significantly lower than that the in normal controls (P < 0.05), the expression level of TGF-β1 mRNA in newly diagnosed ITP patients increases as compared with normal controls (P < 0.05), after treatment with DXM the expression of IL-10 mRNA was enhanced, the expression of TGF-β1 mRNA was reduced as compared with expression level before treatment (P < 0.05). It is concluded that the Breg cells may play an important role in the pathogenesis of ITP via humoral immunity and its regulation of T lymphocytes.

Expression of c/ebpα gene in MDS and its clinical significance / 中国实验血液学杂志

This study was aimed to investigate the expression of CCAAT/enhancer binding protein alpha gene (c/ebpα) in patients with myelodysplastic syndromes (MDS) and to explore the significance of c/ebpα in pathogenesis and progression of MDS. Real time quantitative reverse transcriptase polymerase chain reaction (RQ-PCR) method was used to detect the expression level of c/ebpα mRNA in bone marrow mononuclear cells (BMMNC) of 33 patients with MDS and 14 normal controls. The results showed that the expression level of c/ebpα mRNA in low-risk and high-risk MDS was significantly lower than that of normal controls (p < 0.01, p < 0.001, respectively), moreover, high-risk MDS showed lower c/ebpα mRNA expression compared with low-risk MDS (p < 0.05). c/ebpα mRNA expression level in MDS was not correlated with sex, age and peripheral blood cell amount, while the ratio of blast cells in bone marrow was in the c/ebpα mRNA low expression group significantly higher than that in the high expression group (p < 0.01). It is concluded that down-regulation of c/ebpα mRNA expression level has closely associated with the pathogenesis of MDS, the c/ebpα may be an important molecular biological marker of MDS; the degree of down-regulated c/ebpα has closely related to the progression of MDS.

Comparison of curative efficacy after G-CSF-mobilized sibling HLA-matched peripheral blood hematopoietic stem cell transplantation versus that combined with BMT for patients with hematologic malignancies in a single center / 中国实验血液学杂志

This study was aimed to retrospectively analyze and compare the clinical curative efficacy of patients with hematologic malignancies after G-CSF-mobilized sibling HLA-matched (sm) peripheral blood hematopoietic stem cell transplantation (sm-allo-PBHSCT) and sm-allo-PBHSCT combined with bone marrow transplantation (BMT). 100 patients received sm-allo-HSCT in a single center from October 2001 to October to 2010, included 38 patients received sm-allo-PBHSCT and 62 patients received sm-allo-PBHSCT combined with BMT. The myeloablative or reduced intensity conditioning regimens were chosen according to the condition of patients. All patients received standard cyclosporine (CsA) and mycophenolate mofetil (MMF) as prophylaxis for GVHD. The results showed that the rapid hematopoietic reconstitution was observed in all patients. The median time of ANC ≥ 0.5 × 10(9)/L in both groups were 12 days, the median time of platelet count ≥ 20 × 10(9)/L was 15 days in sm-allo-PBHSCT group and 16 days in sm-allo-PBHSCT + BMT group. The incidence of acute GVHD, acute GVHD of III-IV grade and chronic GVHD in sm-allo-PBHSCT and sm-allo-PBHSCT + BMT groups were 37.1% and 34.2%, 7.89% and 8.06%, 36.11% and 41.38% respectively, there were no statistical differences. The relapse rates were similar in two groups (sm-allo-PBHSCT 13.16% vs sm-allo-PBHSCT + BMT 12.9%). The 3-year disease-free survivals in sm-allo-PBHSC and sm-allo-PBHSCT + BMT groups were 57.1 ± 8.7% and 61.3 ± 6.4% respectively (p = 0.852). The 2-year overall survival of high-risk patients was 41.4 ± 12.8% in sm-allo-PBHSCT group, while 60.9 ± 9.6% in sm-allo-PBHSCT + BMT group (p = 0.071). It is concluded that the rhG-CSF mobilized sibling matched allo-PBHSCT + BMT is superior to the rhG-CSF mobilized sibling matched allo-PBHSCT in increasing the overall survival of high-risk hematologic malignancies.

Detection of Th17/treg cell-associated cytokines in peripheral blood of patients with graft-versus-host disease and its clinical significance / 中国实验血液学杂志

To investigate the peripheral levels and clinical significance of Th17/Treg cell-associated cytokines in patients with acute graft versus host disease (aGVHD) or chronic GVHD (cGVHD), blood samples were collected from 39 hematopoietic stem-cell transplantation patients and 20 healthy donors. The patients included 10 patients with aGVHD, 13 patients with cGVHD and 16 patients without evidence of GVHD. Th17/Treg cell-associated cytokines such as IFNγ, IL-4, IL-6, IL-10, TGF-β(1), IL-17 and IL-23 were detected by ELISA. The results showed that the plasma levels of IFN-γ, IL-4, IL-6, IL-17 and IL-23 significantly increased in patients with aGVHD or cGVHD, compared with the patients without clinical signs of GVHD and the healthy donors (p < 0.05), while IL-10 and TGF-β(1) were obviously lower than that of them (p < 0.05). After aGVHD and cGVHD patients were treated effectively, the plasma levels of IL-6, IL-17 and IL-23 were significantly decreased, and IL-10, TGF-β(1) were significantly increased, while the levels of IFN-γ and IL-4 did not markedly change. The TGF-β(1) level were negatively correlated with IL-6 (r = -0.36, p < 0.05), IL-17 (r = -0.51, p < 0.05) and IL-23 (r = -0.44, p < 0.05) respectively, while there were positive correlations between IL-6 and IL-17 (r = 0.62, p < 0.05), IL-6 and IL-23 (r = 0.71, p < 0.05), IL-17 and IL-23 (r = 0.93, p < 0.05). It is concluded that Th17/Treg cell-associated cytokines may play an important role in the development of a/cGVHD, which helps to find novel targets for developing new strategies of GVHD treatment.

Influence of TLR2 and TLR4 agonists on migration of cord blood CD34(+) cells / 中国实验血液学杂志

This study was aimed to investigate the influence of TLR2 and TLR4 agonists on the migration and adhesion activity of umbilical cord blood (UCB) CD34(+) cells and to explore the underlying mechanism. The expression of TLR2 and TLR4 on UCB CD34(+) cells was detected with flow cytometry. The effect of TLR2 agonist (PAM3CSK4) and TLR2 agonist (LPS) on the migration and adhesion ability of UCB CD34(+) cells was evaluated with chemotaxis and adhesion assays. The results indicated that expression levels of TLR2 and TLR4 were (14.2 ± 3.8)%, (19.6 ± 4.1)% respectively. Compared with the control group, the migration activity of UCB CD34(+) cells toward SDF-1 decreased significantly in LPS group (p < 0.01). The adhesion activity was not altered significantly in LPS group. However, both the migration activity towards SDF-1 and the adhesion activity of UCB CD34(+) cells were not changed significantly in PAM3CSK4 group. Further study found that LPS did not affect the expression level of CXCR4 on CD34(+) cells, but could inhibit the spontaneous migration ability of CD34(+) cells. It is concluded that TLR4 activation can decrease the chemotaxis function of CD34(+) cells towards SDF-1, which may associate with the decreased spontaneous migration ability of CD34(+) cells.

Effect of vascular endothelial growth factor-C on the cell growth and angiogenesis in NB4 cell xenograft tumor / 中华血液学杂志

<p><b>OBJECTIVE</b>To establish NB4/VEGF-C cells xenograft in nude mice model, and explore the effect of VEGF-C on hematological malignancies</p><p><b>METHODS</b>NB4/VEGF-C or NB4/pcDNA3.1 cell lines were established by transfecting the recombinant pcDNA3.1-VEGF-C plasmid and the vacant pcDNA3.1 vector into NB4 cells. The recombinant VEGF-C was identified by RT-PCR and Western blotting. Eighteen male BALB/c nude mice aged 4 - 5 weeks were equally divided into two groups. Mice irradiated by 4 Gy ⁶⁰Co were subcutaneously injected with 1 × 10⁷NB4/VEGF-C or NB4/pcDNA3.1 cells into one side of axilla. The volumes of xenograft tumor was evaluated according to L × t² × 0.52. Microvessel density (MVD) on the xenograft tumor section was detected by IHC with VWF antibody.</p><p><b>RESULTS</b>NB4 cell xenograft tumors were developed in all mice of both the two groups. The growth of NB4/VEGF-C cells in nude mice was faster than in controls. There were statistically significant differences in the volume and weight of xenograft tumor between NB4/VEGF-C and NB4/pcDNA3.1 cell groups \[(631.44 ± 114.42) mm³ vs (491.22 ± 70.05) mm³\] (P = 0.006) and \[(321.78 ± 27.84) mg vs (288.57 ± 40.12) mg\] (P = 0.031), respectively. MVD in xenograft tumor of NB4/VEGF-C cells \[(50.8 ± 11.7)/mm²\] was higher than that in controls \[(18.9 ± 7.0)/mm²\] (P = 0.021). The Bcl-2 protein level in NB4/VEGF-C cells xenografts was higher than that in controls.</p><p><b>CONCLUSION</b>VEGF-C could promote proliferation of NB4 cells by inducing angiogenesis and inhibit cells apoptosis by upregulating antiapoptotic Bcl-2 protein expression in NB4 cells xenograft tumor.</p>

Correlative study between JAK2 mutation and thrombosis in patients with myeloproliferative neoplasm / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the frequency and clinical implication of JAK2 mutation in patients with myeloproliferative neoplasm(MPN)and the correlation between the mutation and thrombosis.</p><p><b>METHODS</b>The clinical and laboratory data of 107 MPN patients was retrospectively analyzed. JAK2 mutation were detected with allele-specific polymerase chain reaction (AS-PCR) and sequencing. The significance of the mutation in disease diagnosis and molecular pathogenesis and the correlation between the mutation and thrombosis was analysed.</p><p><b>RESULTS</b>JAK2 mutation was detected in 71 (66.4%) and thrombosis in 34 (31.8%) of the 107 MPN patients. Thrombosis occurred in 34.8% (16/46) of polycythemia vera (PV), 32.6% (14/43) of essential thrombocythemia (ET), and 22.2% (4/18) of primany myelofibrosis (PMF) patients. The difference among the 3 groups was not significant (χ(2) = 0.96, P > 0.05). The frequency of thrombosis in JAK2(+) MPN patients (82.4%, 28/34) was higher than that in JAK2(-) MPN patients (17.6%, 6/34) (χ(2) = 5.71, P < 0.05). The frequency of thrombosis in MPN patients > 60 years was higher (41.5%, 27/65) than that in patients < 60 years (16.7%, 7/42) (χ(2) = 7.28, P < 0.01).</p><p><b>CONCLUSION</b>JAK2 V617F mutation occurs in significant percentage of Chinese patients with MPN. Patients with JAK2 mutation and older age are more succeptible to thrombosis. JAK2 mutation screening in patients with unknown thrombosis is helpful to reveal the underlying latent-MPN.</p>

Intron 1 and 22 inversions in factor VIII gene in patients with haemophilia A / 中华血液学杂志

<p><b>OBJECTIVE</b>To analyze intron 1 and 22 inversions in factor VIII (FVIII) gene in hemophilia A (HA) patients and and their families and to investigate the correlation between intron inversion and FVIII antibody.</p><p><b>METHODS</b>All patients were detected FVIII: C and FVIII antibody. In addition, 81 unrelated HA patients were directly detected by multiplex PCR and long-distance PCR for intron 1 and 22 inversions in FVIII gene. Pedigree investigation for some patients were conducted.</p><p><b>RESULTS</b>In 81 unrelated HA patients, 3 severe cases were found intron 1 inversion which accounted for 4.6% of total 65 severe cases. Of the 3 cases, one was FVIII antibody positive. Two female family members of a intron 1 inversion patient were identified as one carrier and one non-carrier. Twenty five of 65 (38.5%) severe cases were found intron 22 inversion. Of the 25 cases 1 was FVIII antibody positive. Nine female members in 5 HA families which had patients with intron 22 inversion were identified as 7 carries and 2 non-carriers.</p><p><b>CONCLUSION</b>Besides intron 22 inversion, intron 1 inversion was another important molecular defect in resulting in severe HA. Intron inversion analysis can also be used for deviation rectification of experiment grouping in HA patients. Intron 1 and 22 inversions may be one of the higher risk factors for resulting in FVIII antibodies.</p>

Clinical significance of anticoagulant proteins detection in patients with thrombotic events / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence and the risk of natural anticoagulants such as plasma protein C (PC), protein S (PS) and antithrombin (AT) deficiency in thromboembolic patients with no evident acquired factors.</p><p><b>METHODS</b>Clotting assays on French STAGO autoanalyzer were used to detect the activity of plasma PC, PS and AT in 85 patients with thrombotic disease and 50 sex and age matched healthy controls.</p><p><b>RESULTS</b>Among the 85 enrolled patients (18 arterial and 67 venous thromboembolism), male to female ratio was 1.4 and the median age was 42 years (17-69). The activity of plasma PC, PS and AT in the pre-therapy thrombotic disease group, the thrombo-recurrence group, and the age < or = 45 years group were significantly lower than that is the healthy control group, the first thrombotic episodes group and the age > 45 years group respectively (P < 0.001, P < 0.01, P < 0.01). The overall deficiency rate of these three natural anticoagulants was 30.6%, PS deficiency was the commonest (10.6%), the second was PC deficiency (8.2%), AT deficiency and combined deficiency each accounted for 5.9%.</p><p><b>CONCLUSION</b>The PC, PS and AT protein deficiencies are frequent in Chinese thromboembolic patients, they are the independent risk factors for the thrombotic events and recurrence.</p>

Identification of a novel mutation of F (13) A gene in a pedigree with factor XIII deficiency / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore F (13) A gene mutation in a pedigree with hereditary coagulation factor XIII (FXIII) deficiency.</p><p><b>METHODS</b>The FXIII deficiency was diagnosed by clot solubility test and other standard laboratory clotting tests. All exons, exon-intron boundary sequences of F(13) A gene were amplified by PCR and the products were sequenced directly. Any mutation identified by direct sequencing was confirmed by reverse sequencing. The mutation identified in the proband was screened in the family members.</p><p><b>RESULTS</b>The assays of PT, Qiulan, fibrinogen leveling, platelet counts, bleeding time were normal and the clot solubility test was positive in the proband. The homozygous deletion of 33 nucleotides (127067de133) in exon 10 of F(13) A gene which resulted in deletion of 11 amino acids in FXIIII A protein with 720aa residues was identified in the proband. Family studies showed that the mutation was inherited from the parents both of whom carried the heterozygous deletion mutation.</p><p><b>CONCLUSION</b>The homozygous 127067de133 mutation of F(13) A gene is responsible for the disorder of the pedigree.</p>

The effect of on VEGF-C cDNA transfection on NB4 cell proliferation, differentiation and resistance to apoptosis / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the biological effect on NB4 cells proliferation, all-trans retinoic acid (ATRA) inducing differentiation and resistance to apoptosis by vascular endothelial growth factor (VEGF)-C cDNA transfection.</p><p><b>METHODS</b>The recombinant eukaryotic expression plasmid pcDNA3.1-VEGF-C and the vacant pcDNA3.1 vector were introduced separately into NB4 cells by lipofectamine mediation. The positive clones were screened by G418 and identified by reverse transcriptase-PCR (RT-PCR) and Western blotting. The proliferation capacity of NB4/VEGF-C cells was analysed by MTT assay and colony forming assay in vitro. After NB4/VEGF-C cells were induced by ATRA, the expression level of C/EBPalpha gene, CD11b on cells surface and morphological alteration were analysed by real-time quantitative PCR (RQ-PCR), flow cytometry (FCM), and Wright-Giemsa staining, respectively. FCM Annexin V-FITC/PI dual labeling technique was performed to investigate the etoposide (Vp16) induced NB4/VEGF-C cells apoptosis and bcl-2 gene expression level in these cells was analysed by RQ-PCR. The NB4/pcDNA3.1 cells was used as control in the above experiments.</p><p><b>RESULTS</b>A stable NB4 cell line that secrets VEGF-C and its control lines were established. The proliferation capacity of the former was stronger than that of the latter. The expression level of C/EBPalpha gene of NB4/VEGF-C cells on ATRA treatment was only 1/32 that of NB4/pcDNA3.1 cells. The CD11b level and the degree of differentiation of NB4/VEGF-C were weaker than that of NB4/pcDNA3.1 cells. The percentage of apoptotic NB4/VEGF-C cells induced by Vp16 [(7.20 +/- 2.52)%] was significantly lower than that of NB4/pcDNA3.1 cells [(16.07 +/- 3.58)%] (P = 0.005), but the bcl-2 gene expression level of NB4/VEGF-C cells is 2.28-fold that of NB4/pcDNA3.1 cells.</p><p><b>CONCLUSION</b>The VEGF-C via VEGFR-3 signaling pathway could promote the proliferation of leukemic cells by autocrine pathway and inhibit the cell differentiation mediated by ATRA and chemotherapy-induced apoptosis. VEGF-C/VEGFR-3 signaling loops might play an important role in disease progression and be potential therapeutic target for the treatment of leukemias.</p>

Quantitative analysis of gene expression for vascular endothelial growth factor and its application / 中国实验血液学杂志

Vascular endothelial growth factor (VEGF), a central mediator of angiogenesis, not only plays an important role in the pathogenesis of leukemia, but also is an independent prognostic factor in patients with hematologic malignancies, like those in solid tumors. However, the importance of VEGF during differentiation or apoptosis of leukemia cells remains to be elucidated. In order to assess the alternation of VEGF gene expression in the process of all-trans retinoic acid (ATRA)-induced differentiation of NB4 acute promyelocytic leukemia cell line, and a competitor DNA fragment, VEGF gene competative template (T-VEGFDelta) was constructed by using gene recombinant technologies, and a competitive quantitative reverse transcriptase-polymerase chain reaction (cQRT-PCR) method was developed. A standard curve was obtained by co-amplification of serial dilutions of the target nulecules with constant amount of competitive template and this curve was used to detect molecular number of target gene in measuring sample. The surface expression of CD11b antigen and nitroblue tetrazolium (NBT) reduction rate of NB4 cells were also assayed at different time points. The results showed that cQRT-PCR was a sensitive, reliable tool for analysis of VEGF gene expression with a detectable range from 1 x 10(4) to 2 x 10(5) molecules. The number of VEGF gene transcripts detected by means of cQRT-PCR assay was 42.3 x 10(5), 12.6 x 10(5), 3.6 x 10(5), and less than 1.0 x 10(5)/microg total RNA at 0, 12, 24 and 48 hours after ATRA treatment, respectively. This rapid down-regulation of VEGF gene expression, during ATRA-induced NB4 cell differentiation, was accompanied by the up-regulation of CD11b expression and an increased NBT reduction rate. In conclusion, cQRT-PCR method was successtully constructed, confirming that ATRA efficiently repressed VEGF, at the same time, the ATRA might exert an antileukemic effect, other than induction of differentiation via inhibition of angiogenesis.