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Objective: To detect the relative expression of IGLL1 (immunoglobulin lambda-like polypeptide 1) mRNA in bone marrow of children with T-cell acute lymphoblastic leukemia (T-ALL), and analyze its correlation with the clinical characteristics and prognosis of the patients, so as to clarify the clinical significance of IGLL1 in pediatric T-ALL patients., Methods: A total of 56 pediatric T-ALL patients hospitalized in Children's Hospital of Soochow University from June 2012 to December 2017 and treated with CCLG-ALL 2008 regimen were selected. Transcriptome sequencing technology was used to detect the transcription level of IGLL1 gene in children with T-ALL. According to 25% of the IGLL1 transcription level (cutoff value:448), the enrolled children were divided into IGLL1 low expression group (17 cases) and IGLL1 high expression group (39 cases). Combined with clinical data, the correlation between the expression level of IGLL1 and prognosis of the patients was analyzed., Results: The comparative analysis showed that the transcription level of IGLL1 was not correlated with the clinical characteristics of the patients, such as sex, age, bone marrow blast, white blood cell (WBC) count at initial diagnosis. The 5-year OS rate of patients with high IGLL1 expression was significantly higher than that of patients with low IGLL1 expression (76.9%±6.7% vs 47.1%±12.1%, P =0.018). Further comparison of relapse-free survival (RFS) rate between the two groups showed that the 5-year RFS rate of patients with high IGLL1 expression was higher than that of patients with low IGLL1 expression, but the difference between the two groups was not statistically significant ( P =0.095). Multivariate COX analysis was conducted on common clinical prognostic factors (age, sex, WBC count at diagnosis, prednisone response on the 7th day, bone marrow response on the 15th day after treatment) and IGLL1 expression level, and the results showed that IGLL1 expression ( P =0.012) and prednisone response ( P =0.017) were independent risk factors for overall survival in pediatric T-ALL patients., Conclusion: In pediatric T-ALL, the OS rate of children with high expression of IGLL1 gene was significantly higher than that of children with low expression of IGLL1 gene, and the expression level of IGLL1 gene was an independent factor affecting the survival of children with T-ALL, which suggests that IGLL1 is a marker of good clinical prognosis of children with T-ALL.

Objective: To analyze the effect of clinical features, routine laboratory examination and related gene mutation on the OS of patients with myelodysplastic syndrome (MDS) after hematopoietic stem cell transplantation (HSCT)., Methods: 121 patients diagnosed as MDS and underwent hematopoietic stem cell transplantation in the First Affiliated Hospital of Soochow University from October 2013 to August 2018 were selected. Basic information of the patients was collected, and blood cells, bone marrow blasts at initial diagnosis, chromosomal karyotypes and gene mutations of the patients were detected.The effect of different factors on overall survival (OS) was analyzed by statistical method., Results: Kaplan-Meier univariate analysis shows that OS was significanly different among different age groups. The 3-year OS rate of patients aged 0-29 years was (83.3±7.7) %, the 3-year OS rate in patients aged 30-49 years was (58.1±7.7 %), and the 3-year OS rate of patients aged 50-69 years was (31.0±22.6) %, which was statistically different (P＜0.05) between different groups. There were also significant differences in OS among patients with different transplantation types. 3-year OS rate: HLA-matched sibling HSCT＞unrelated HLA-matched HSCT＞haploidentical HSCT＞micro HSCT. The OS rate of patients with bone marrow blasts≥10% seems lower than blasts＜10%, but there was no statistical difference.The 3-year OS rate of patients with chromosomal karyotype complex abnormality was (47.7±11.5) %, and that of patients without complex abnormality was (80±4.2) % which was statistical difference (P＜0.05). Patients with DNMT3A, NRAS, TP53 and GATA2 mutations had shorter OS time compared with patients without mutation of these genes, which shows statistically significant (P＜0.05). COX multivariate analysis showed that age, chromosome karyotype, DNMT3A, TET2, GATA2 and NRAS were the independent factors influencing OS of patients after HSCT, with statistically significant difference., Conclusion: age of patients, donor selection of HSCT, chromosome karyotype, DNMT3A, NRAS, TP53, GATA2 and TET2 gene mutations are all independent factors affecting the OS of patients after HSCT. Therefore, the assessment of the OS of MDS patients with transplantation requires comprehensive consideration.

Objective: To investigate the gene mutation types and gene carrying rate of common thalassemia in patients with thalassemia in Quanzhou, and to analyze its molecular epidemiological characteristics in Quanzhou., Methods: 546 patients with thalassemia diagnosed at the first hospital of Quanzhou from January 2017 to October 2018 were collected and retrospectively analyzed for their types of mutations and carrier rates., Results: Among the 4226 samples submitted, 546 positive samples were detected, the total carrying rate of the thalassaemia genes was 12.92%; the carrier rate of α-thalassemia was 8.16%; the carrier rate of β-thalassemia was 4.76%; There were more α-thalassemia missing patients than non-deleted patients. The Southeast Asian deletion type (-- SEA /αα) was the most common one, with a composition ratio of 68.98%, which was followed by 22.61% (-α 3.7 /αα), 2.61% (α WS α/αα), and 2.32% (αα CS /αα), 2.32% (α QS α/αα), 1.16% (-α 4.2 /αα); 9 types of β-thalassemia gene mutations were detected. The most common three mutations were IVSII-654 (C→T, 42.29%), CD41-42 (-TTCT, 33.83%), CD17 (A→T, 12.94%). 2 cases of -- THAI /αα , 1 case of αα/ααα anti3.7 and 1 case of HKαα were detected., Conclusion: This study shows that the gene carrying rate of thalassemia in Quanzhou is high and has diversity, which can provide some reference for the prevention and control of thalassemia in Quanzhou.

Objective: To investigate the gene prevalence and spectrum of thalassemia in the women of childbearing age in quanzhou area., Methods: Venous blood of the women were collected for study, all subjects were registered in each county of quanzhou area by using cluster sampling. Both the mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were used for screening thalassemia．Genotyping of the screened positive samples was performed by gap single polymerase chain reaction (gap-PCR) and reverse dot blot (RDB) hybridization．Unknown positive samples were analyzed with DNA sequencing., Results: Out of all 7 082 samples, Three hundred and eighty four were identified as thalassemia gene carriers with a carrying rate of 5.42 %. The α and β thalassemia were 3.21% and 2.15% respectively. -- SEA /αα was the most common genotype with 68.72 % in mutation types of α thalassemia, In addition gene, 2 cases of -- THAI /αα and 1 case of αα/ααα anti3.7 were also detected. IVS-Ⅱ-654/N and CD41-42/N were the most common gentypes with 75.00 % in mutation types of β thalassemia gene, 5 cases were found to be α β compogite thalassemia., Conclusion: The carrying rate of thalassemia gene in quanzhou area is higher, and with the most common gentypes including -- SEA /αα、IVSⅡ-654(C→T)/N and CD41-42(-TTCT)/N. The study results are beneficial for the screening of thalassemia in the genetic consultation and the prenatal gene diagnosis.

Objective: To investigate the effect of transcriptional regulation of aberrant transcription factor AML1-ETO on p14 ARF ., Methods: P14 ARF expression both in AML1-ETO-expressing cells or U937 nonexpressing cells and in leukemia cells of AML patients with or without t(8;21) was assessed by quantitative PCR. Methylation-specific polymerase chain reaction (MSP) was used to analyze the methylation status of p14 ARF promoter. The chromatin immunoprecipitation (ChIP)-based PCR was used to investigate the direct interaction between the AML1-ETO and p14 ARF promoter in AML1-ETO positive leukemia cell line. And the p14 ARF mRNA expression level was detected by qRT-PCR after treatment with 5-Aza., Results: AML1-ETO-expressing cell subclone displayed low level of p14 ARF mRNA in comparison with the non-transfected U937. In primary bone marrow cells of acute myeloid leukemia containing AML1-ETO, level of p14 ARF mRNA was markedly lower when compared with other acute myeloid leukemias lacking this translocation. P14 ARF gene promoter was non-methylated in control group and primary leukemia cells of AML patients without t(8;21) and was hyper-methylated in U937-A/E1-4 and primary leukemia cells of AML patients with t(8;21). The enriched regions in transfected cells were located within p14 ARF promoter. 5-Aza could increase the expression of p14 ARF ., Conclusion: P14 ARF is a possible target gene of AML1-ETO. The p14 ARF silencing induced by hyper-methlylation may be an important factor for occurrence and development of the M 2b subtype of acute myeloid leukemia.

Objective: To explore the differentiation-inducing potentiality of Pulsatilla saponin A on K562 cells., Methods: Pulsatilla saponin A of different concentrations was used to treat K562 cells; the benzidine staining and the hemoglobinometry were applied to measure the change of hemoglobin content; the flow cytometry (FCM) was used to detect the expression of CD71 and GPA on K562 cells., Results: K562 cells treated with 4 µg/ml pulsatilla saponin A differentiated into the erythroid lineage. With the treatment of pulsatilla saponin A, the hemoglobin content in K562 cells increased significantly; CD71 and GPA expression on the K562 cell surface were up-regulated., Conclusion: Pulsatilla saponin A can induce K562 cells to differentiate into erythroid lineage.

Objective: To explore the autophagy activity of CD34+ cells in bone marrow of MDS patients and its clinical significance., Methods: The activity of autophagy in bone marrow CD34+ cells from 20 MDS patients, 20 non-malignant anemia patients and 5 AML patients admitted in our hospital from October 2012 to March 2014 was detected by flow cytometry (FCM)., Results: The autophagy activity in low risk MDS patients and non-malignant anemia patients were both significantly higher than that in both high risk MDS and AML patients (P<0.05), and more interestingly, the autophagy activity in MDS negatively correlated with World Health Organization classification-based prognostic system (WPSS) score (r=-0.877) ., Conclusion: The autophagy activity CD34+ cells in the patients with MDS is higher than that in AML patients, and negatively correlated with WPSS scores, indicating that the decrease of autophagy activity maybe accelerate the genesis and development of MDS and relate with the prognosis of MDS patients.

Most Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) patients often show rapid recurrence and development of ABL kinase domain (KD) mutation after tyrosine kinase inhibitor (TKI) treatment. To further investigate the mechanism of Ph(+) ALL fast relapse after TKI treatment, ABL KD mutation in 35 Chinese Ph(+) ALL with TKI resistance was detected by direct sequencing. The results showed that 77.1% (27/35) Ph(+) ALL patients with TKI resistance had ABL KD mutation and 55.6% (15/27) Ph(+) ALL patients with ABL KD mutation had T315I. Interestingly, 77.8% (21/27) Ph(+)ALL showed ABL mutation G: C→A:T, including T315I, E255K and E459K. Furthermore, all the Ph(+) ALL patients with two or more ABL KD mutations collaborated with complex chromosome abnormality and all the TKI-resistant Ph(+) ALL patients, whose karyotype progressed from simple t (9;22) into complex, developed ABL KD mutation. Moreover, the expression level of uracil-DNA glycosylase UNG2, which inhibits G:C→A:T transition in genomic DNA, decreased in Ph(+) ALL with TKI-resistance compared to that in newly diagnosis Ph(+) ALL. It is concluded that there is a high frequent ABL KD G:C→A:T mutation and a high genomic instability in Chinese TKI-resistant Ph(+) ALL. In addition, the decreased UNG2 expression in TKI-resistant Ph(+) ALL probably contributes to their high rate of ABL KD G:C→A:T mutation.

This study was aimed to investigate the effect of AML1-ETO fusion protein on the anti-apoptotic gene BCL-2 in leukemic cells and to explore its role in leukemogenesis. The apoptotic levels of U937-WT, U937-Mock and U937-A/E1-4 cells were examined by flow cytometry. And cleaved caspase-3 protein expression was detected by Western blot. BCL-2 gene expression both in AML1-ETO-expressing cells or U937 nonexpressing cells and in leukemia cells of AML patients with or without t(8;21) was assessed by quantitative PCR. The chromatin immunoprecipitation (ChIP)-based PCR was used to investigate the direct interaction between the AML1-ETO and BCL-2 promoter in AML1-ETO positive leukemia cell line. The results indicated that in U937-A/E cells but not in U937-WT or U937-Mock cells, apoptotic cells statistically significantly increased, and AML1-ETO expression also significantly enhanced activation of caspase-3. AML1-ETO-expressing cell subclones displayed significantly low levels of BCL-2 mRNA in comparison with the non-transfected U937. In primary bone marrow cells of acute myeloid leukemia containing AML1-ETO, levels of BCL-2 mRNA were markedly lower as compared with other acute myeloid leukemias lacking this translocation. The enriched regions in transfected cells were located within BCL-2 promoter. It is concluded that BCL-2 is the direct target gene of AML1-ETO. AML1-ETO can down-regulate the expression of BCL-2.

This study was aimed to explore the contribution of autophagy associated gene Beclin1 in the prognosis of myelodysplastic syndrome (MDS) by detecting the expression level of Beclin1 in bone marrow mononuclear cells (BMNC) from 40 MDS patients, 14 non-malignant anemia patients and 25 AML patients. The expression of Beclin1 mRNA was detected by real-time quantitative polymerase chain reaction (qRT-PCR). At the same time, the Western blot was used to analyze the expression of Beclin1 proteins. The results showed that the expression of Beclin1 in low risk MDS patients and non-malignant anemia patients was both significantly higher than that in acute myeloid leukemia patients (P < 0.01). And more interestingly, the Beclin1 mRNA expression in MDS group was negatively correlated with World Health Organization classification-based prognostic system (WPSS) score (r = -0.495). It is concluded that the expression of Beclin1 in the patients with MDS is higher than that in AML patients, and negatively correlated with WPSS scores. Beclin1 is a potential biomarker for predicting prognosis of the patients with MDS.

In order to study the potential of Venus, lentiviral vector, applied to acute myeloid leukemia, the recombinant vector Venus-C3aR was transfected into 293T packing cells by DNA-calcium phosphate coprecipitation. All virus stocks were collected and transfected into HL-60, the GFP expression in HL-60 cells was measured by flow cytometry. The expression level of C3aR1 in transfected HL-60 cells was identified by RT-PCR and flow cytometry. The lentiviral toxicity on HL-60 was measured by using CCK-8 method and the ability of cell differentiation was observed. The results indicated that the transfection efficacy of lentiviral vector on HL-60 cells was more than 95%, which meets the needs for further study. C3aR1 expression on HL-60 cells increased after being transfected with recombinant lentiviral vector. Before and after transfection, the proliferation and differentiation of cells were not changed much. It is concluded that the lentiviral vector showed a high efficacy to transfect AML cells and can be integrated in genome of HL-60 cells to realize the stable expression of interest gene. Meanwhile, lentiviral vector can not affect HL-60 cell ability to proliferate and differentiate.

This study was purpose to explore whether the dysplasia of myelodysplastic syndromes (MDS) is unspecific feature or results of the abnormal clone, and to provide the evaluation of abnormal clone changes in bone marrow cells of MDS patients. The dysplasia cells in bone marrow smears was analyzed by morphologic observation, the clonal origin and development in 16 cases of MDS with abnormality of chromosome karyotypes were investigated by FISH combined with morphologic observation. The results found that both the dysplastic and nondysplastic bone cells displayed abnormal clones in the erythroid and granulocytic cells. The dysplastic bone marrow cells displayed more abnormal clones than the nondysplastic bone marrow cells in most of the patients, and the abnormal clones displayed more dysplastic cells than the normal clones. Most of the dysplastic and nondysplastic megakaryocytes were derived from abnormal clones. The abnormal clone showed a decreasing trend from the primitive stage to the terminal stage of cell differentiation. It is concluded that there is a correlation between the dysplastic cells and the abnormal clones in MDS, but the dysplasia of bone marrow cells is not a specific feature. The abnormal clones can differentiate into mature granulocytes and erythrocytes, and can be in coexistence with cells originated from the normal clones.

To investigate the effects of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor simvastatin (SV) on proliferation, apoptosis and the PI3K/AKT signaling pathway in human acute monocytic leukemia cell line SHI-1. SHI-1 cells were incubated with different concentrations of SV (5, 10, 15 µmol/L). Otherwise, SHI-1 cells without any treatment were used as control. Cells in different groups were collected at 24, 48 and 72 h after incubation for further detection. MTT method was used to assay the growth inhibition rate and flow cytometry was used to detect the early stage apoptosis ratio. The human PI3K-AKT Signaling Pathway RT(2) Profiler(TM) PCR Array was used to detect the expression of 84 genes involved in PI3K-AKT signaling. The results indicated that the SV inhibited the proliferation and inducted the apoptosis of SHI-1 cells in time- and dose-dependent manners significantly. The growth inhibition rates of SHI-1 cells treated with 15 µmol/L SV for 24, 48 and 72 h were 26.82, 47.09 and 63.92, respectively; and their early stage apoptosis ratios were 5.75, 13.25 and 15.59, respectively. Compared with the control group, expression levels of 39 genes were changed in the group of 15 µmol/L SV at 48 h, among them 26 genes were down-regulated and 13 genes were up-regulated. It is concluded that the SV can inhibit proliferation and induce apoptosis of SHI-1 cells, and the mechanism may be associated with the changes of gene expression level in PI3K-AKT signaling pathway regulated by SV.

The aim of this study was to construct venus vector carrying the gene encoding insulin-like growth factor binding protein 7 (IGFBP7), which provides an effective platform for exploring the function of this gene in leukemia. After digestion by restriction endonuclease, the IGFBP7 gene was recombined with the transfer plasmid. The venus particles were packaged using 293T cells to transfect K562 cells, and identification was performed by means of flow cytometry, RT-PCR and Western blot. The results showed that the sequence of cloned IGFBP7 gene was the same as that in GenBank. The size of product restricted by BamHI was same as the predicted one. GFP expression was observed in 293T and K562 cells with the fluorescent microscopy and flow cytometry. The expression level of mRNA and protein of IGFBP7 was confirmed by RT-PCR and Western blotting in K562 cells. It is concluded that venus vector carrying IGFBP7 gene has been successfully constructed and provides basis for exploring function of IGFBP7 in K562 cells.

Chronic myeloid leukemia (CML) is a malignant clonal disease derived from hematopoietic stem cells. CML stem cells were thought to be the root which could lead disease development and ultimately rapid change. However, a stable animal model for studying the characteristics of CML stem cells is currently lacking. This study was aimed to establish a transplanted human CML nude-mice model to further explore the biological behavior of CML stem cells in vivo, and to enrich CML stem cells in nude mice by series transplantation. The 4 - 6 weeks old BALB/c nude mice pretreated by splenectomy (S), cytoxan intraperitoneal injection (C) and sublethal irradiation (I) were transplanted intravenously with (5 - 7) × 10(7) of bone marrow mononuclear cells from CML patients in chronic phase. Alternatively, 4 - 6 weeks old BALB/c nude mice pretreated by lethal irradiation were transplanted intravenously with 5 × 10(6) homologous bone marrow cells of BALB/c nude mice together with (5 - 7) × 10(7) of bone marrow mononuclear cells from CML patients in chronic phase simultaneously. The leukemic cells engrafted and infiltrated in organs and bone marrow of the mice were tracked by reverse transcription-polymerase chain reaction (RT-PCR), plastic-embedded biopsy and flow cytometry. The results of these two methods were compared. The results showed that human CML cells engrafted and infiltrating into the bone marrow of two nude mice pretreated with SCI could be detected. In spite of the low successful rate, results suggested the feasibility of this method by using BALB/c nude mice as a human CML animal model. In contrast, in nude mice pretreated by the lethal dose irradiation, CML cells in the bone marrow could not be found. It is concluded that human bone marrow CML cells can results in leukemia in nude mice pretreated by SCI. Thus this study provides a new strategy for establishment of CML animal models which deserves further elaboration.

This study was purposed to investigate the expression of the growth-factor independence 1 (GFI1) in patients with leukemia and its clinical significance. Bone marrow mononuclear cells were obtained from 65 newly diagnosed leukemia patients including 24 acute myeloid leukemia (AML), 18 chronic myelogenous leukemia (CML), 6 acute lymphoblastic leukemia (ALL), 17 blast crisis of chronic myelogenous leukemia and 13 patients with iron deficiency anemia (IDA) were used as controls. The relative expression of gene gfi1 was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and taqman quantitative real-time reverse transcription polymerase chain reaction (QRT-PCR). The results showed that gene expression of gene gfi1 in leukemia patients was obviously higher than that in controls and the difference was statistically significant (p < 0.01), in which the expression of gene gfi1 in newly diagnosed CML patients was higher than that in newly diagnosed AML, newly diagnosed ALL, CML-BCP patients and the difference was significant (p < 0.01). Expression of gene gfi1 in lymphocytic blast crisis of CML was higher than that in nonlymphocytic blast crisis of CML, and the difference was significant. It is concluded that gene gfi1 may play an important role in leukemia, especially in CML incidence and progression. The high level expression of gene gfi1 may be participate in the development of lymphoma.

The aim of this study was to investigate the apoptosis-inducing effect of anti-CD44 monoclonal antibody IM7 on chronic myeloid leukemia (CML) stem/progenitor cells in vitro and to explore its possible mechanism. Leukemic stem/progenitor cells (LSPCs) expressing CD34(+), CD38(-) and CD123(+) were isolated from bone marrow (BM) cells of 20 patients with newly-diagnosed chronic myeloid leukemia by using EasySep(TM) magnetic beads. The percentage of apoptotic CML-LSPCs was assayed by Annexin-V/PI staining; the expression changes of c-myc and NF-kappaB mRNA were detected by real-time quantitative PCR (RQ-PCR) and RT-PCR; the NF-kappaB activity was detected by NF-kappaB Activation Nuclear Translocation Assay Kit; the BCL-2 protein expression was determined in the Western blot method. The results showed that the IM7 effectively induced apoptosis of CML-LSPCs; the mean percentage of early apoptotic cells significantly increased, as compared with the untreated control CML-LSPCs cells 12.58 +/- 2.84% vs 5.42 +/- 1.84% (p < 0.05). The c-myc, NF-kappaB mRNA expressions were down-regulated as compared with the control group (0.65 +/- 0.10 vs 1.00, 0.42 +/- 0.21 vs 1.00, respectively) (p < 0.01) by RQ-PCR and (0.49 +/- 0.09 vs 0.60 +/- 0.12, 0.47 +/- 0.11 vs 0.67 +/- 0.08, respectively)(p < 0.01) by RT-PCR. The BCL-2 protein level in CML-LSPCs treated with IM7 also decreased as compared with the control group (p < 0.01). In addition, the depression of NF-kappaB activity was observed through fluorescence microscope. It is concluded that the anti-CD44 monoclonal antibody IM7 effectively induces apoptosis of CML-LSPCs through down-regulating c-myc and bcl-2 mRNA expression, and decreasing NF-kappaB activity in CML-LSPCs.

Rap1 is a small G protein belonging to the RAS superfamily. Rap1 signalling has effects on cell growth, cell proliferation and involves in regulation of the mitogen activated protein (MAP) kinase or ERK (extracellular signal regulated kinase) cascade. Rap1 will directly activate ERK through B-Raf. B-Raf is a member of Raf family, and presents in neuronal and hematopoietic cells. Oncogenic mutations of gene RAS are most frequent and detected in 20% - 30% of human leukemias and 10% - 15% of MDS cases. The review summarizes the regulatory function of Rap1 in development of hematopoietic cells and effect of Rap1 in hematologic malignancies.

Previous study on the gene expression profile of human MDS by using microarray discovered that transcription of RAP1GAP was up-regulated, which was confirmed by quantitative RT-PCR in expanding cohort of MDS patients. This study was pourposed to investigate the expression of RAP1GAP in human MDS and its clinical relevance. The expression of RAP1GAP in bone marrow cells of 19 MDS patients was detected by flow cytometry and was compared with that in patients with non-malignant blood diseases and acute leukemias, meanwhile the relevance between expression level of RAP1GAP and hemoglobin, leukocytes, platelets, blasts percentage in bone marrow cells and IPSS score was analyzed. The results indicated that the expression level of RAP1GAp in MDS patients significantly increased as compared with patients with non-malignant blood diseases or AML (8.42 +/- 8.37% vs 2.97 +/- 4.75% or 2.26 +/- 4.24%). Among MDS patients, the expression level of RAP1GAP in MDS-RA was significantly higher than that in MDS-RAEB (11.64 +/- 9.07% vs 4.37 +/- 4.65%). However, no definitive correlation of expression level with above-mentioned clinical parameters was found in detected patients with DMS. In conclusion, the expression of RAP1GAP in MDS patients obviously increases, the relationship between expression level of RAP1GAP and laboratory hematological parameter and IPSS score does not be confirmed. The role played by RAP1GAP expression in the pathogenesis of MDS and its clinical significance during progression of MDS towards AML deserves further studies.

This study was aimed to investigate the expressions of human telomerase reverse transcriptase (hTERT) and survivin gene in patients with myelodysplastic syndrome (MDS), and to explore their relationship. The expression of hTERT mRNA in bone marrow mononuclear cells (BMMNCs) of 56 patients with MDS and 27 patients with iron deficiency anemia were detected by RT-PCR, the expressions of survivin gene in BMMNCs of 55 patients with MDS and 12 patients with iron deficiency anemia were detected by real-time RT-PCR. The results showed that the expression of hTERT significantly elevated in RA and RAEB patients, as compared with controls (p<0.005). With the disease alleviated, the expression of hTERT decreased and had no significant difference from the controls (p>0.25). There was no significant difference in expression of hTERT between low+int-1 risk group and int-2+high-risk group by IPSS (p>0.50). The expression of survivin gene significantly increased in RA and RAEB patients, as compared with controls (p<0.02, p<0.05). The expression of survivin gene in low+int-1 risk group by IPSS was significantly higher than that in the controls (p<0.02), and there was no significant difference in expression of survivin gene between int-2+high-risk group patients and the controls (p>0.10). It is concluded that the expressions of hTERT and survivin may play a critical role in escaping malignant clone of MDS from apoptosis and acquiring the ability to divide unlimitedly.

This study was aimed to investigate the biological characteristics of osteoblasts and their hematopoietic supportive function by using human fetal osteoblastic cell line 1.19 (hFOBs) as a model. The pluripotency markers (Oct-4, Rex-1, hTERT) of hFOBs were analyzed by RT-PCR, the multilineage differentiation experiments were conducted in vitro. Flow cytometry (FCM) was used to identify the surface markers of hFOBs, and RT-PCR was used to analyze their hematopoietic cytokine expression in comparison with bone marrow mesenchymal stem cell (BM-MSC). The results showed that hFOBs expressed several ESC pluripotency markers including Oct-4 and Rex-1, except hTERT. Moreover, hFOBs could also undergo multilineage differentiation into the mesodermal lineages of adipocytic cell types in addition to its predetermined pathway, the mature osteoblast. Both hFOBs and BM-MSC expressed CD44, CD73 (SH3), CD105 (SH2) and CD90 (Thy1), and lack expression of CD34, CD45, or HLA-DR surface molecules. In addition, both hFOBs and BM-MSC expressed SCF, IL-6, and SDF-1alpha mRNA, but only hFOBs could express GM-CSF and G-CSF. It is concluded that human fetal osteoblastic cell line 1.19 may provide a good model to study the osteoblastic regulation role in hematopoiesis in vitro.

This study was aimed to investigate the biological characteristics of osteoblasts from patients with myelodysplastic syndrome (MDS) and their supportive capacity for hematopoiesis in vitro. A two-dimensional culture system was constructed by using osteoblasts derived from human marrow mesenchymal stem cells (MSC); MSCs were isolated from bone marrow of MDS patients and normal individuals and were cultured; the third passage of MSCs were induced into osteoblasts which were treated with mitomycin C and confluenced into a feeder layer. Ficolled bone marrow mononuclear cells were obtained from normal individuals and seeded into the two-dimensional culture system to culture in vitro without exogenous cytokines. By using colony-forming assay, the ability of the two-dimensional system to culture HPCs was observed. The cytokine expression of osteoblasts from MDS patient bone marrows in mRNA level was detected by RT-PCR and was compared with human osteoblast cell line hFOB1.19. The results showed that the osteoblasts from MDS patients could support short-term survival of GM-CFC in condition without exogenous cytokines, that is, osteoblasts played a crucial role in regulation of HPC growth. The results of RT-PCR clearly demonstrated that the osteoblast cell line hFOB1.19 expressed SCF, IL-6, SDF-1alpha, G-CSF and GM-CSF. The same expression patterns of above cytokines were also seen in osteoblasts derived from BM-MSCs of MDS patients and normal individuals, but these cells did not express GM-CSF. It is concluded that the biological characteristics of osteoblasts from bone marrow of MDS patients are generally not different from those of osteoblasts from normal bone marrow. Both of them can support GM -CFC to form colonies in vitro, it may be associated with expressing important related cytokines by osteoblasts.

The objective of study was to investigate tissue-specific transcriptional activity of WT1 (Wilms' tumor gene) promoter and enhancer in cell lines with diverse tissue origin for leukemic gene therapy depending on WT1 transcriptional regulation elements. WT1 promoter and enhancer were ligated into pEGFP-1 to construct a recombinant vectors with EGFP gene as a reporter. By using electroporation or lipofectamine, the resultant constructs were transfected into 13 cell lines including WT1-expressing hematopoietic cell lines (K562, NB4, THP-1 and SHI-1), WT1-nonexpressing hematopoietic cell lines (U937 and Jurkat), WT1-expressing nonhematopoietic cell lines (MCF-7, T47D and 293) and WT1-nonexpressing nonhematopoietic cell lines (ECV304, SMMC7721, HT-29 and SHG44). The mean fluorescence intensity (MFI) of EGFP representing the transcriptional activities of promoter and/or enhancer was analyzed by using flow cytometry in the transfected cells which stably expressed EGFP. The results indicated that the vectors, pEWP containing WT1 promoter and pEWPA containing both WT1 enhancer and promoter, were constructed by recombinant DNA technique. Among nonhematopoietic cell lines, pEWP induced the highest EGFP expression in ECV304 (16.54 +/- 2.45 times as high as pEGFP-1), mildly higher in MCF-7 and SHG44 (9.46 +/- 1.10 and 7.29 +/- 0.73 times of pEGFP-1 level), and lowest in HT-29 (0.99 +/- 0.02 times as much as pEGFP-1) respectively. Among hematopoietic cell lines, EGFP expression was highest in K562 cell line (2.93 +/- 0.27 times of pEGFP-1), which was statistically higher than those in Jurkat and SHI-1 cell lines (0.74 +/- 0.03 and 0.84 +/- 0.09 times of pEGFP-1 level) respectively. pEWPA, with WT1 enhancer inserted at Afl II site near SV40 polyA, increased basal transcription levels of the WT1 promoter in HT-29, SHI-1 and K562 cells by 4.81, 3.06 and 1.01-fold respectively. It is concluded that the transcriptional activities of WT1 promoter in the recombinant vector seem unrelated to the constitutional expression level of endogenous WT1 gene. The WT1 enhancer promotes the transcriptional activities of WT1 promoter in some of the cell lines regardless of the hematopoietic tissue origin.

The study was aimed to investigate the immunophenotypic and cytogenetic features of chronic lymphocytic leukemia (CLL) in order to provide an evidence for diagnosis and therapy. Immunophenotypic analysis was performed by using a panel of monoclonal antibodies and three-color immunofluorescence staining methods of flow cytometry in 51 patients with CLL, and the cytogenetic features were analyzed by R-banding technique. The results indicated that among 51 CLL cases, the positive rate of CD19 and CD23 was 96.1%, followed by CD15 (94.1%), CD20 (82.4%) and CD22 (78.4%). The positive rate of CD38 was 23.5%. Forty-six patients expressed both CD5 and CD19. Seven main clonal chromosomal abnormalities were detected by conventional cytogenetics (CC) in eighteen cases (35.3%), with three cases of +12, two cases of 13q(-), other chromosomal abnormalities included +14, 6q(-), t (11; 14), t (14; 18) and t (2; 7). Expression of the antigens had no relationship with chromosomal abnormalities. It is concluded that typical CLL express CD5, CD19 and CD23, and the positive rate detected by CC in CLL is low. Immunophenotyping in combination with cytogenetic technique plays an important role in the diagnosis and prognosis of CLL.

In order to investigate the feasibility of using EGFP as a reporter gene in WT1 transcriptional regulation study. WT1 promoter and enhancer were ligated into the vector pEGFP-1 by recombinant DNA technique and confirmed by restriction enzymes digestion. The resultant constructs were transfected into K562 cell line by DMRIE-C reagent and the function of these WT1 gene elements was detected by using a fluorescent microscope after transfection for 48 hours. The results indicated that the recombinant vectors, pEWP containing WT1 promoter, and pEWPE, pEWPA and pEWPD harboring both WT1 enhancer and promoter, had been successfully constructed. Fluorescence was observed in K562 cells transfected by pEWP, pEWPE, pEWPA and pEWPD, while no fluorescence could be detected in cells transfected by pEGFP-1. It is concluded that EGFP gene as a reporter gene can be applied to the WT1 transcriptional regulation study, which provides the basis for gene therapy.

In order to study the potential effects of exogenous WT1 gene isoform on apoptosis in leukemia cell line NB4 and its possible molecular mechanisms, the eukaryotic expression recombinant vector (pCB6(+)/WTA) containing full-length human WT1 isoform (WTA: -17aa/-KTS) cDNA and the vacant vector-alone were introduced into the leukemia cell line NB4 respectively by electroporation. The WTA mRNA and protein in cells were detected by RT-PCR and Western blot. Binding of Annexin V were tested by flow cytometry and agarose gel electrophoresis to verify whether exogenous WTA could induce apoptosis of NB4 cells. Expressions of p21, p53, bcl-2, bcl-XL and c-myc genes were determined by semi-quantitative RT-PCR after introducing recombinant vectors into the NB4 cells. The results showed that in exposure to As(2)O(3) at 0.8 micromol/L for 48 hours, the NB4/WTA cells exhibited the morphological hallmarks of apoptosis, the marked DNA ladder shown by gel electrophoresis, and the enhanced apoptosis rate marked by Annexin V. RT-PCR showed an increase in p21 and c-myc genes expression, a decrease in bcl-2 and a relative constant expression of p53, bcl-XL in NB4/WTA cells. It is concluded that the introduction and expression of exogenous WTA gene can lead to apoptosis of NB4/WTA cells by down-regulating the Bcl-2 gene expression and up-regulating the p21 and c-myc genes expression.

To explore the feasibility of real-time quantitative PCR (QRT-PCR) for selecting cell strains which overexpress a certain transgene, expression level of RbAp46 was detected in transfected cell strains by using optimal real-time PCR with SYBR Green I. Meanwhile, semi-quantitative RT-PCR and Western blot were performed to compare with the QRT-PCR. The results showed that values of RbAp46(N) were 2064.42 +/- 253.47, 860.94 +/- 291.07, 234.456 +/- 31.08, 18.17 +/- 5.14 and 1.46 +/- 0.54 in K562/RbAp46, K562/CMV, SHG44/RbAp46 monoclone, SHG44/RbAp46 multiclone and SHG44/CMV, respectively. The results were consistent with that determined by semi-quantitative RT-PCR and Western blot. It is concluded that QRT-PCR provides a highly efficient and reproducible method for selection of transfected cell subclones at different level of transgene expression.

To elucidate the possible mechanism of differentiation and/or apoptosis in NB4, K562 cells induced by tributyrin (TB), a histone deacetylase inhibitor (HDACi), the level of acetylated histone H3 was detected by Western blot, p21(WAF1) expression was detected by semi-quantitative RT-PCR. The results showed that histone H3 hyperacetylation was detected in NB4 (or K562) cells after treatment with TB 0.1 mmol/L (or TB 0.5 mmol/L) for 16 hours in a dose-dependent manner. p21(WAF1) dose-dependently increased at RNA level in these two cell lines treated by TB 0.1 mmol/L. The level of p21(WAF1) mRNA increased at 2 hours after TB treatment, reaching peak at 16 hours, and maintaining for 48 hours. In conclusion, the mechanism of differentiation and apoptosis in NB4, K562 cells induced by tributyrin may associate with its up-regulation of acetylated histone and p21(WAF1) mRNA level.

cDNA microarray, recently applied to analyze gene expression profile of cancers, was difficult to be utilized in myelodysplastic syndrome (MDS) for a special need of excessive mRNA hardly provided by ordinary bone marrow aspiration in MDS patients. The aim of this study was to investigate the feasibility of exploring the molecular events underlying MDS by using cDNA microarray and mixing mRNA from multiple patients. A commercially purchased BioStar H141 cDNA microarray containing 14,110 clones of cDNA or EST was employed to analyze the gene expression profile of bone marrow mononuclear cells from two cases of MDS. Equal amount of total RNA from each patient was mixed, reversely transcribed to cDNA and labeled with Cy5. Mixture of Cy5-labeled cDNA and Cy3-labeled cDNA from normal bone marrow cells was concomitantly hybridized to H141 microarray in duplicate. In H141 chips, 1,064 cDNAs were spotted at least twice targeting different fragments of a single gene cDNA. The results showed that among these 1,064 cDNA clones, the expression level of 625 (58.7%) and 630 (59.2%) ones was consistent within these two chips, respectively, 297 (27.9%) and 191 (18.0%) inconsistent, 21 (2.0%) and 11 (1.0%) in opposite. Among 411 duplicately spotted cDNAs with complete data, expression levels of 400 (97.3%) was consistent between two chips. 488 genes with known function were identified as differentially expressed in MDS, among which 101 genes were involved in hematopoiesis regulation, including those encoding transcription factors, cell cycle-regulating proteins, metabolism-relating enzymes, and adhesive molecules. It is concluded that cDNA microarray can be used for profiling gene expression of mixed MDS samples and replication shall be necessary for reducing the data bias caused by experimental operation.

To establish leukemic cell lines stably transfected by RbAp46 gene, electroporation was performed after optimizing the transfection condition for suspended cells. Under conditions of low voltage and high capacitance, RbAp46 was transfected into U937 by electroporation. Individual clones selected with G418 for 3 weeks were isolated. The integration and the protein levels of the exogenous RbAp46 in transfectants were determined by PCR and Western blot analysis, respectively. The subclone expressing high level of RbAp46 was then established. Viability of transfected cells was assayed by trypan blue exclusion. Cell number was counted daily to determine the growth rate. The results showed that growth rate of U937 cell lines expressing exogenous RbAp46 was about 50% lower than that in control. It is concluded that leukemic cell lines stably expressing exogenous RbAp46 were established and overexpression of RbAp46 inhibits the growth of U937 leukemic cells.

TNF-related apoptosis-inducing ligand (TRAIL) is a newly identified member of the tumor necrosis factor (TNF) family. TRAIL induces apoptosis by activating caspase cascades, stimulating a loss of mitochondrial membrane potential (Delta Psim) and cytochrome C release in the FADD/caspase-8 dependent pathway. However, TRAIL can also trigger transcriptional activations of the pro-oncogene of c-fos, JNK, and NF-kappaB by other signaling pathways downstream of FADD/caspase-8. MAPK/ERK activation has a dominant protecting effect over apoptotic signaling from the death receptors. The functional expression of TRAIL by leukemic cells may be involved in tumor cells evasion of immunosurveillance. Somatic mutations of TRAIL-R1 and TRAIL-R2 genes may play a role in the pathogenesis of some tumors. TRAIL can induce apoptosis on various continuous transformed cell lines and primary tumor cells, including several of hematopoietic origin, displaying minimal toxic effects on normal tissues. Because of the abilities of induction of both cytotoxic (apoptosis) and cytostatic (cell cycle perturbation) effects on the leukemic cells, TRAIL is currently considered as a potential(co) therapeutic drug against tumors.

To elucidate the effect of established primary bone marrow stromal layers on the gene transduction of human hematopoietic stem/progenitor cells (HSC/HPC), mononuclear cells (MNC) from adult bone marrow were isolated by centrifugation on Ficoll-Hypaque gradients and plated in stromal culture medium. The cells were incubated until passage 4 to establish primary stromal layers. The HSC/HPC prestimulated by cytokines were transduced by retroviral supernatant containing mdr1 gene in presence of irradiated stroma-contact support. Transduced cells were plated in a colony-forming unit assay with and without vincristine (VCR) to assess the efficiency of transduction. Individual colonies were also analyzed by polymerase chain reaction (PCR) for the presence of provirus. The results showed that the mixed adherent cell layers were formed when adult bone marrow stromal cells were incubated for four to six weeks, mainly being composed of fibroblasts. In the presence of stroma-contact support, the average of gene transduction efficiency in marrow-derived progenitors increased 2.1 to 3.3 folds measured by colony-forming assay and/or PCR, significantly higher than those without support of stroma. It is concluded that the presence of bone marrow stroma support in combination with cytokine facilitates augmenting the extent of retroviral-mediated gene transduction.

WT1 gene encodes a zinc finger transcription factor that regulates transcription of its downstream genes. Some of target genes for WT1 are involved in regulating both cell cycle and cellular proliferation and differentiation. However, WT1 itself is regulated by its upstream genes such as NF-kappaB and GATA-1. Thus there exists a pathway of transcriptional regulation mediated by WT1, which controls development of hematopoietic system. Leukemia results from disrupting the homeostasis among hematopoietic proliferation, differentiation and apoptosis, which is often the consequence of an inappropriate expression of transcription factors and subsequent disruption of the normal gene expression pattern. This article reviews the relationship between the WT1-mediated pathway of transcriptional regulation and leukemia.

The identification of genes inducing resistance to anticancer chemotherapeutic agents and their introduction into hematopoietic cells represents a promising approach to overcome bone marrow toxicity, the limiting factor for most high-dose chemotherapy regimens. Because resistance to cyclophosphamide has been correlated with increased levels of expression of the aldehyde-dehydrogenase (ALDH1) gene in tumor cells lines in vitro, this study tested whether ALDH1 overexpression could directly induce cyclophosphamide resistance. Results showed that a retroviral vector was used to transduce full-length human ALDH1 cDNA into human hematopoietic cell line K562 that was then tested for resistance to 4-hydroxycyclophosphamide (4-HC), an active analogue of cyclophosphamide. Overexpression of the ALDH1 gene resulted in a significant increases in cyclophosphamide resistance in transduced K562 cells (50% inhibition concentration, IC50 = 10 micro mol/L). These findings indicate that ALDH1 overexpression is sufficient to induce cyclophosphamide resistance in vitro and provide a basis for testing the efficacy of ALDH1 gene transduction to protect bone marrow cells from high-dose cyclophosphamide in vivo.

To study the telomerase activity in the bone marrow MNCs from patients with myelodysplastic syndromes in comparison with that in normal individuals and acute leukemia patients. The intracellular telomerase activity was semi-quantitatively examined by PCR-ELISA assay in the marrow cells of 20 normal individuals, 21 cases of myelodysplastic syndromes (MDS) and 32 cases of acute leukemia. Telomerase activity in normal marrow cells was 0 - 0.30 U, with a mean level of (0.11 +/- 0.08) U, in which 3 cases were considered positive according to the standard set by the Kit. In 32 acute leukemia patients, the mean level of telomerase activity was (0.42 +/- 0.26) U (ranged 0 - 0.96 U) with a positive rate of 78.1%, showing a significantly higher activity in acute leukemia (P < 0.01). Moderate telomerase activity was detected in 21 cases of MDS, with a mean level of (0.27 +/- 0.19) U (0 - 0.97 U) from which the positive rate was 66.7%. This value was significantly higher than that in the normal BM (P < 0.05). Moreover, a significantly higher telomerase activity was shown in the high-risk group of MDS (P < 0.05). Based on the international scoring system evaluating the prognosis of MDS (IPPS), telomerase activity in HIGH subgroup was significantly higher than that in INT-1 and INT-2 subgroup (P < 0.05). The level of telomerase activity was not correlated to the chromosome aberrations. These results show that a borderline telomerase activity could be found in normal bone marrow cells. Telomerase activity was markedly higher in acute leukemia. BM of MDS patients demonstrated a moderate telomerase activity. Higher telomerase activity could be found in high-risk group and correlated with poor prognosis.

In order to study the relation between WT1 gene expression and differentiation of NB4 leukemic cells, a competitive RT-PCR method was established by using recombinant DNA technique to detect the expression of WT1 gene quantitatively during differentiation of NB4 leukemic cells induced by retinoic acid. The expression of CD11b was simultaneously determined by an indirect immunofluorescence staining technique and flow cytometry. Our results showed that WT1 gene expression rapidly decreased during the differentiation of NB4 cells. The molecular number of WT1 gene in 1 micro g total RNA was 4 x 10(6), 1.56 x 10(6) and 0.4 x 10(6), respectively, prior to and at 12 or 24 hours after exposure to retinoic acid, and it was in accordance with the change of CD11b. These data suggest that the abnormally high expression of WT1 gene in leukemic cells was associated with the block of cell differentiation. The detection of WT1 expression with competitive RT-PCR combined with measure of CD antigens will contribute to study on the differentiation induction of leukemic cells.