Analysis of Immunophenotypes in 329 Patients with B-ALL at Different Ages / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the immunophenotypes of B cell acute lymphoblastic leukemia (B-ALL) in patients at different age and to explore its clinical application in prognosis prediction and individualized treatment.</p><p><b>METHOD</b>The immunophenotyping in 329 patients with B-ALL at different ages was performed by CD45/SSC gate four-color fluorescence flow cytometry.</p><p><b>RESULTS</b>In all patients detected the highest incidence of lymphoid-associated antigens was CD19, HLA-DR, CyCD79a and cTdT, followed by CD10, CD22, CD34, CD38, CD20 and CyIg. B-ALL showed a higher concomitant expression rate of myeloid antigens CD13 and CD33; the CD11b, CD15, CD117 and T antigens (CD4, CD7 and CD56) were rarely expressed. CD10⁻ pro-B acute lymphoblastic leukemia (Pro - B-ALL) was predo-minant in infantile group (60%) with CD117 higher expression (40%). Subtype Pro-B-ALL was rarely expressed in childhood and adolescent group, but the incidence of disease increased as the age increase, the incidence of youth group (22.7%) and middle-aged' group (14.8%) were significantly higher than childhood group (4.4%). The influence of age on immunophenotypic characteristics of the adult B-ALL was not significant, the heterogeneity of antigen expression was less in the adult patients at different ages. The expression of CD10 and CD38 was lower, while expression of CD34, CD13 and CD33 were higher in adult patients than those in children patients. There was no significant difference in incidence of precursor-B-ALL (Pre-B-ALL) among different age groups (P > 0.05), but its incidence increased along with age increasing, and the expression of CD20 was higher in Pre - B-ALL than that in Pro - B-ALL and common B-ALL.</p><p><b>CONCLUSION</b>The immunophenotype characteristics of B-ALL in the patients at different ages is of great value in prediction for disease prognosis and guidence of individualized treatment.</p>

Investigation on the mechanisms of p15INK4B gene demethylation by valproate in Molt-4 cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the antitumour effects of sodium valproate (VPA) on the proliferation, differentiation and cell cycle of Molt-4 cell and to investigate its demethylation mechanisms.</p><p><b>METHODS</b>After Molt-4 cells trated with VPA at different concentrations, cell viability and growth curve were assessed by MTT assay. Cell cycle changes were analyzed by flow cytometry. The expression level of p15, DNA methyltransferase 1 (DNMT-1), DNMT3A and 3B mRNA were detected by RT-PCR and the methylation level was detected by hn-MSPCR.</p><p><b>RESULTS</b>VPA significantly inhibited the proliferation of Molt-4 cells. After 48 h culture with 5.0 mmol/L VPA, the percentages of Molt-4 cells in G(0)/G(1) phase was (66.87 ± 3.31)% and in S phase was (8.47 ± 2.56)%, while in control group, the cells in G(0)/G(1) phase increased and in S phase decreased significantly. The p15 gene in Molt-4 cells failed to express due to its hypermethylation. The expression level of p15 gene mRNA increased significantly after exposure to VPA for 48 h. As compared with control group, the expression of DNMT-1 was down-regulated in a dose-dependent manner. The expression level of DNMT3B decreased at 10.0 mmol/L concentration.</p><p><b>CONCLUSION</b>VPA has a demethylation effect on p15 INK4B gene by inhibiting the DNMT-1 and DNMT3B gene activities to recover p15 gene activity, which arrests Molt-4 cell in G(0)/G(1) phase.</p>