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

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

Establishment of a rat silicosis model via non-exposed tracheal instillation in combination with a ventilator / 中国职业医学

@#Objective - To establish a new non exposed intratracheal instillation method for establishing a rat silicosis model. Methods ， The specific pathogen free SD rats were randomly divided into control group and experimental group with ten rats in ， each group. Rats in the control group were given 1.0 mL of 0.9% sodium chloride solution and rats in the experimental group - were given 1.0 mL of silica suspension with a mass concentration of 50 g/L adopting to the one time intratracheal instillation ， - ， method and then followed by ventilator assisted ventilation immediately. When the tidal volume stabilized at 2.0 mL the ventilator was removed and the tracheal intubation was pulled out. Five rats in each group were sacrificed after two and four ， - Results weeks after modeling and hematoxylin eosin staining and Masson staining of lung tissue were performed. There was ， ， no death in the two groups of rats during the experiment. After two and four weeks the control group had normal lung structure ， ， ， normal alveolar cavity size no inflammatory cell infiltration thin alveolar wall only a small amount of collagen distribution ， around the lung interstitium and bronchus. At the second week of modeling the alveolar wall of the rats in the experimental ， ， ， group was slightly thickened interstitial lymphocytes and macrophages were infiltrated slight hyperplasia was found and a ， small amount of fibroblasts were visible. At the 4th week of modeling the alveolar wall of the rats in the experimental group was ， ， ， ， significantly thickened fibrous nodules were formed and fibroblasts fibrocytes collagen fibers were significantly increased. Conclusion - The combination of ventilator and non exposed intratracheal instillation method can be used to successfully ， ， . establish a rat silicosis model which is simple safe and effective

Retrospective analysis and discussion on 74 cases of adverse reactions of traditional Chinese medicine injection / 中国中药杂志

As a modern dosage form drug with rapid effect, traditional Chinese medicine (TCM) injection has been more and more used in clinical practice. Meanwhile the safety of TCM injection has attracted more and more attention. The retrospective analysis on 74 cases of adverse reaction of TCM injections collected from 2007 to 2016 in the Third Affiliated Hospital of Beijing University of Chinese Medicine showed that the proportion of men and women with adverse reactions was 0.54:1; the average age was 62.5 years old; 21 kinds of TCM injections were involved. Among them, the most reported were blood-regulating agents. The top four kinds of TCM injections with highest adverse drug reactions (ADRs) were Tanreqing injection, Danhong Injection, Shuxuening Injection and Xuesaitong for injection. The top three clinical manifestations of adverse reactions were lesions of skin and its appendages, damage of circulatory system and damage of nervous system. The potential causes of the adverse reactions of TCM injections were analyzed, and it was believed that individual difference, medicine, pharmaceutical excipients, solvent and TCM syndrome differentiation may be the main five causes for the adverse reactions of TCM injections. In order to reduce the adverse reactions of TCM injections, it is suggested that the clinical pharmacists should participate in the application management of TCM injections in the hospital; the production enterprises shall strengthen the whole life cycle management of the drugs; and at the same time, the drug control and administration authorities should improve the drug management methods constantly and encourage the development of TCM injections to the high quality level.

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

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

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

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

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

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

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

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

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

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

Gene mutations and clinical manifestations in children with glycogen storage disease type Ib / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Glycogen storage disease type Ib (GSDIb) is caused by a deficiency of glucose-6-phosphate translocase (G6PT) activity due to SLC37A4 gene mutations. Most GSDIb patients have recurrent infections and inflammatory bowel disease, with poor prognosis. Detection of SLC37A4 gene mutations is of great significance for the diagnosis, subtyping and outcome prediction of GSD patients. This study aims to analyze SLC37A4 gene mutations in Chinese GSDIb patients and to investigate the relationship between its genotypes and clinical manifestations.</p><p><b>METHODS</b>All exons and their flanking introns of SLC37A4 gene in 28 Chinese children with a primary diagnosis of GSDIb were screened by PCR combined with direct DNA sequencing to detect SLC37A4 gene mutations.</p><p><b>RESULTS</b>Five SLC37A4 gene mutations were detected in 7 (25%) of the 28 children, i.e., p.Gly149Glu (9/13, 69%), p.Gly115Arg (1/13, 8%), p.Pro191Leu (1/13, 8%), c.959-960 insT (1/13, 8%) and c.870+5G>A (1/13, 8%).</p><p><b>CONCLUSIONS</b>In this study, c.959-960 insT is a novel mutation and p.Gly149Glu is the most common mutation. p.Gly149Glu may be associated with severe infections in children with GSDIb.</p>

Enzymatic diagnosis and clinical characteristics of 52 children with mucopolysaccharidosis / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore the incidence of various types of mucopolysaccharidosis (MPS) and their clinical characteristics.</p><p><b>METHODS</b>A total of 75 children highly suspected as having MPS underwent quantitative and electrophoretic analysis of urinary glycosaminoglycans (GAGs) and enzymatic analysis of seven types of MPS from January 2009 to December 2011. Fluorescence assay was used to measure the activities of α-L-iduronidase, iduronate-2-sulfatase, α-N-acetylglucosaminidase, galactosamine-6-sulfatase, β-galactosidase, arylsulfatase B and β-glucuronidase in the white blood cells.</p><p><b>RESULTS</b>A total of 52 cases were confirmed with MPS based on clinical, radiological, and enzymatic examinations. The 52 cases, with a mean age of 4.0 ± 2.2 years, included 5 cases of MPS I (10%), 20 cases of MPS II (38%), 20 cases of MPS IVA (38%), 6 cases of MPS VI (12%) and 1 case of MPS VII (2%). No MPS IV B cases or MPS IIIB cases were found. Compared with healthy children of the same age, the GAG/Cr ratio was significantly elevated in 50 confirmed cases of MPS (two MPS IVA cases having no increased ratio). All children with increased urinary GAGs had a confirmed diagnosis of MPS. The age of onset was between 1 and 2 years after birth in most cases, and often complicated by hernia and valvular heart disease. Children with MPS I, MPS II, and MPS VI presented with ugly and unsmooth face, short stature, joint stiffness, and limitation of motion, while children with MPS IVA presented with short stature, skeletal dysplasia, and joint laxity.</p><p><b>CONCLUSIONS</b>Type IVA and type II are the most common in MPS cases, followed by type VI and type I. MPS children are characterized by special appearances including ugly and unsmooth facial appearance, short stature and skeletal dysplasia. Quantitative analysis of urinary GAG, as a simple, rapid, and reliable method, is recommended for screening of MPS.</p>

Fut1 gene mutation for para-bombay blood type individual in Fujian Province of China / 中国实验血液学杂志

This study was aimed to investigate the molecular mechanisms for para-Bombay blood type individual in Fujian Province of China. The para-Bombay blood type of this individual was identified by routine serological techniques. The full coding region of alpha (1,2) fucosyltransferase (FUT1) gene of this individual was amplified by polymerase chain reaction (PCR), then the PCR product was cloned into T vector. The mutation in coding region of fut1 gene was identified by TA cloning, so as to explore the molecular mechanisms for para-Bombay blood type individual. The results indicated that the full coding region of fut1 gene was successfully amplified by PCR. AG deletion at position 547-552 on 2 homologous chromosomes was detected by TA cloning method, leading to a reading frame shift and a premature stop codon. It is concluded that genetic mutation of fut1 gene in this para-bombay blood type individual was h1h1 homozygotic type.

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

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

Effect of triptolide on reversing hypermethylation of apc gene in Jurkat cells and its possible mechanisms / 中国实验血液学杂志

This study was aimed to investigate the effect of traditional Chinese medicine, Triptolide (TPL) on reversing hypermethylation of antioncogene (apc gene) in acute lymphoblastic leukemia cell line Jurkat in vitro and to explore its mechanisms. The effects of TPL on cell growth, proliferation and cell cycle were detected by growth curve, MTT assay, colony formation test and flow cytometry, respectively. The effect of TPL on apc gene methylation of Jurkat cells was analyzed by nested methylation specific PCR; the expressions of apc gene, dnnt3a, dnmt3b mRNA were measured by RT-PCR; the protein expression of apc gene was detected by Western blot. The results showed that as compared with untreated control cells, the TPL of different concentrations could significantly inhibit growth and proliferation of Jurkat cells in dose-and time-dependent manners with IC₅₀ 19.7 ng/ml at 48 hours. All cytosines in CpG dinucleotides in untreated Jurkat cells had no changed, while all cytosines in Jurkat cells treated with TPL had been converted to thymidine suggesting the methylation of apc gene in Jurkat cells. The TPL could reverse hypermethylation of apc gene and induced the mRNA and protein expression of apc gene in dose-dependent manner. It is concluded that the small dose of TPL can obviously suppress the proliferation of Jurkat cells, activate and up-regulate the expression of apc gene through demethylation of apc gene resulting from DNMT and/or direct action, thereby inhibit the proliferation rate of Jurkat cells.

Expression of Maf-b mRNA in de novo leukemia patients and its clinical significance / 中国实验血液学杂志

This study was aimed to quantitatively detect the level of maf-b mRNA in leukemia patients and evaluate its clinical significance. Real-time fluorescence quantitative PCR was used to detect the relative expression level of maf-b mRNA. The expression change of maf-b mRNA in various types of leukemia was analyzed. Then, the relationship of maf-b mRNA expression with laboratory index and the response to chemotherapy was analyzed. The results showed that maf-b mRNA expression level in acute myeloid leukemia (AML) patients was lower than that in normal group (p<0.01) and positively correlated with white blood cell count (p<0.01) and the expression of CD34 (p<0.01). There was no correlation between maf-b mRNA expression level and chemotherapy response in AML patients except for acute promyelocytic leukemia (APL). Maf-b mRNA expression levels in acute lymphoid leukemia (ALL) and chronic myeloid leukemia (CML) patients were also lower than that in normal group (p<0.01). It is concluded that there is low expression of maf-b gene in AML patients. Abnormal expression of maf-b correlates with abnormal proliferation of AML cells, which may be a new prognostic factor for AML.

Effect of epigallocatechin-3-galate on human acute monocytic leukemia cell line U937 and its relevant mechanism / 中国实验血液学杂志

The purpose of this study was to explore the effect of epigallocatechin-3-galate (EGCG) on acute monocytic leukemia cell line U937 and its relevant mechanism. The viability of U937 cells were assayed by SRB method. The cell cycle of U937 cells was analyzed by flow cytometry. The mRNA and protein expression of p16 gene were detected by RT-PCR and Western blot, respectively. Methylation level of U937 cells was analyzed by n-MSP. The mRNA expression of DNA methyltransferase 1 (DNMT1), DNMT3A and DNMT3B genes were analyzed by RT-PCR. The results showed that EGCG could inhibit the growth of U937 cells significantly in dose-and time-dependent manners (r=0.71), and induce the G0/G1 arrest of U937 cells in dose-dependent manner. EGCG could up-regulate the mRNA and protein expression of P16 gene in U937 cells in dose-dependent manner. EGCG could down-regulate the methylation level of p16 gene in U937 cells in dose-dependent manner. EGCG could down-regulate the mRNA expression of DNMT3A, DNMT3B genes, while did not influence the mRNA expression of DNMT1 gene. It is concluded that EGCG can up-regulate the mRNA and protein expression of p16 gene by demethylation or/and by inhibiting DNMT3A and DNMT3B genes, leading, in turn, to G0/G1 arrest and growth inhibition of U937 cells.

Arsenic trioxide reverses hypermethylation of p16 and activates its transcription in malignant lymphoma cell line CA46 / 中国实验血液学杂志

This study was aimed to investigate the reversing effect of arsenic trioxide (As2O3) on methylation status and the regulatory effect on transcription of malignant lymphoma cell line CA46 p16 gene as well as their possibe mechanisms. The hypermethylated malignant lymphoma cell line CA46 was used as a subject of experiment for studying relation of gene methylation with expression. The effect of As2O3 on the proliferation and viability of CA46 was detected by SRB method, the change of p16 methylation status after exposure to As2O3 was determined by nMSP, the expressions of p16, DNMT1, DNMT3A, DNMT3B mRNA were assayed by RT-PCR, the influence of As2O3 on CA46 cell cycle was analyzed by flow cytometry using analytical method for DNA ploidy. The results showed that the methylation level of p16 gene was obviously reduced after treatment with As2O3 for 72 hours and the hypermethylation of p16 gene was successfully reversed; the expression of p16 gene in untreated (control) group was low while it was enhanced in treated groups; the gray scale ratios of p16 gene to beta-actin in groups treated with As2O3 of concentration 0.5, 1.0 and 2.0 micromol/L were 0.33+/-0.10, 0.57+/-0.11 and 0.67+/-0.09 respectively, exhibiting a significant difference in comparison with 0.73+/-0.13 of positive control (p<0.01); as compared with the untreated group, the expression of DNMT3A and DNMT3B in treated groups was obviously down-regulated in a concentration-dependent manner, while expression of DNMT1 was nearly unchanged; as compared with control, all the 3 different concentrations of As2O3 could inhibit the proliferation of CA46 cells and increase the cell number in G0/G1 phase. It is concluded that the As2O3 may up-regulate the expression of p16 gene, recover the activity of p16 gene, thereby promote the regulatory function on cell cycle resul-ting in arrest of cells in G0/G1 phase and inhibit growth of tumor cells through depressing the expression of DNMT3A and DNMT3B and/or directly reversing the methylation status of p16 gene.

Detection of APC gene promoter methylation in hematological malignant cell lines by nested-methylation specific polymerase chain reaction / 中国实验血液学杂志

This study was aimed to investigate the efficiency of nested methylation specific polymerase chain reaction (nMS-PCR) for detecting the APC gene promoter methylation and to clarify the roles of methylation in genesis and development of hematologic malignancies, as well as to screen the hematologic malignant cell lines with hypermethylation of APC gene promoter to use as an ideal cell model for exploring the relationship between gen methylation and gene expression. The genome DNA of 10 cell lines modified with bisulfide was amplified and the methylation status of APC gene promoter was detected by using nMS-PCR. The results showed that the methylation of APC gene promoter was detected in Jurkat cells, while could not be detected in CA46, U266, Molt4, K562, HL-60, CEM, AKR, U937 and Raji cell lines. In conclusion, APC gene methylation in hematological malignant cell lines can be accurately detected by nMS-PCP method, which is simple method for detecting methylation status of various hematological malignant cell lines.

Demethylation and transcription of p16 gene in malignant lymphoma cell line CA46 induced by EGCG / 中国实验血液学杂志

The study was purposed to investigate the possible mechanism of epigallocatechin-3-gallate (EGCG) induced p16 gene demethylation and transcription regulation in the malignant lymphoma cell line-CA46. The induced growth inhibition of CA46 cells was assayed by growth curve and MTT; the DNA content of CA46 cells was analyzed by flow cytometry after being exposed to EGCG; the methylation status of the p16 gene in CA46 cell line before and after treatment with EGCG was detected by the nested-methylation specific PCR and DNA sequencing; the mRNA of p16 and DNA methyltransferases (DNMT3A and DNMT3B) gene were determined by RT-PCR. The results showed that in comparison with the control, all the 3 different concentration of EGCG were able to inhibit the growth of malignancy cell lines and increase the cell number in G(0)/G(1) phase. After treatment with EGCG for 48 hours, the methylation level was apparently attenuated in a concentration-dependent manner. Expression of p16 gene in untreated group was mild while in the treated groups it had been greatly strengthened, as compared with untreated group, the gray scale ratio of p16 to beta-actin 1 treated with EGCG (6, 12, 24) microg/ml was increased from (0.05 +/- 0. 01) to (0.19 +/- 0.03), (0.39 +/- 0.10), (0.85 +/- 0.09) respectively, exhibiting a significant difference (p < 0.05); as compared with the untreated group, after treatment with EGCG for 48 hours, the expressions of DNMT3A and DNMT3B were obviously down-regulated. It is concluded that EGCG can activate and up-regulate the expression of p16 gene mRNA which inhibits the proliferation of CA46 cell through inducing the G(0)/G(1) arrest by demethylation and/or by inhibiting DNMT3A and DNMT3B gene.

Synergistic effects of VPA and As2O3 on Molt-4 cells in vitro and its possible mechanisms / 中国实验血液学杂志

This study was purposed to investigate the synergistic effects of sodium valproate (VPA) and As2O3 on the proliferation of Molt-4 cells in vitro and its possible mechanisms. Cell viability and growth curve were assessed by the MTT assay. The synergistic activity in combination of 2 drugs was determined by the Q format. The expression levels of p15, DNA methyltransferase 1 (DNMT-1), DNMT3A and DNMT 3B mRNA were detected by RT-PCR and the methylation level was detected by hn-MSPCR. The results indicated that the VPA and As2O3 both inhibited proliferation of Molt-4 cells. The combination of two drugs showed an additive effect (values of Q were>or=0.85). The inhibitory rate in combination of 5 mmol/L of VPA with 10 micromol/L of As2O3 was (70.31+/-2.54)%. The p15 gene in Molt-4 cell line failed to express due to its hypermethylation. The level of p15 gene mRNA expression increased significantly after exposure to VPA in combination with As2O3 for 48 h. As compared with control group, the expression of DNMT-1 was down-regulated in a dose-dependent manner, whereas DNMT3A had no significant differences from the control. The level of expression of DNMT3B seemed to decrease at 10 mmol/L concentration. There were significant differences between the combination of the two drugs and the control group. The gray value of methylated bands decreased after the treatment of VPA alone and in combination with As2O3 in a dose-dependent manner. It is concluded that VPA induces demethylation of p15 INK4B gene by inhibiting the DNMT-1 and DNMT3B gene activities, which up-regulates the p15 gene, recovers its activity. The combination of VPA with As2O3 has the synergistic additive effect on the inhibition of cell viability, so that VPA can reduce the side effect of As2O3 on liver function, which would be verified in the clinical practice.

Detection of p16 gene methylation status in adult patients with acute leukemia by using n-MSP / 中国实验血液学杂志

The study was aimed to explore the relationship between patterns of methylation or deletion and the development of acute leukemia, and further to clarify the possible mechanism in the development of adult acute leukemia. Nested methylation-specific polymerase chain reaction (n-MSP) was adopted to analyze p16 gene methylation or deletion patterns in 82 adult acute leukemia patients with different subtypes and stages. The results indicated that rate of p16 gene methylation was 39.0% in 82 adult acute leukemia patients, among them, 41.4% in acute myelogenous leukemia (AML) and 33.3% in acute lymphoblastic leukemia (ALL). It were found that 36.6% of de novo AL patients and 54.5% of relapsed AL patients developed the hypermethylation of p16 gene. Out of the 82 patients, 6 seemed to have deletion of p16 gene, including 1 AML (1.7%) and 5 ALL (20.8%). There were no hypermethylation or deletion of p16 gene in the 16 controls. It is concluded that methylation of p16 gene may play a more important role than homozygous deletion of p16 gene in the leukemogenesis and progression of adult acute leukemia.