Selenoprotein S (SelS) is widely expressed in diverse tissues where it localizes in the plasma membrane and endoplasmic reticulum. We studied the potential function of SelS in erythrocyte differentiation using K562 cells stably overexpressing SelS wild-type (WT) or one of two SelS point mutants, U188S or U188C. We found that in the K562 cells treated with 1 microM Ara-C, SelS gradually declined over five days of treatment. On day 4, intracellular ROS levels were higher in cells expressing SelS-WT than in those expressing a SelS mutant. Moreover, the cell cycle patterns in cells expressing SelS-WT or U188C were similar to the controls. The expression and activation of SIRT1 were also reduced during K562 differentiation. Cells expressing SelS-WT showed elevated SIRT1 expression and activation (phosphorylation), as well as higher levels of FoxO3a expression. SIRT1 activation was diminished slightly in cells expressing SelS-WT after treatment with the ROS scavenger NAC (12mM), but not in those expressing a SelS mutant. After four days of Ara-C treatment, SelS-WT-expressing cells showed elevated transcription of beta-globin, gamma-globin, epsilon-globin, GATA-1 and zfpm-1, whereas cells expressing a SelS mutant did not. These results suggest that the suppression of SelS acts as a trigger for proerythrocyte differentiation via the ROS-mediated downregulation of SIRT1.
beta-Globins ; Cell Cycle ; Cell Membrane ; Cytarabine ; Down-Regulation ; Endoplasmic Reticulum ; epsilon-Globins ; Erythrocytes ; gamma-Globins ; K562 Cells ; Selenoproteins

β-thalassemia is a chronic hemolytic anemia characterized by the reduction or absence of synthesis of β-globin chains because of the β-globin gene mutations. β-thalassemia belongs to the inherited hemoglobin disease, and occurs in some provinces of China, such as in Guangdong, Guangxi, Fujian, its prevalence is about 2%. The treatment of this disease include transfusion, iron chelating agent, hematopoietic stem cell transplantation, splenectomy, induced expression of Fetal Hemoglobin (HbF) and gene therapies. However, the mortality rate of this disease is still higher, thus some new treatments are urgently needed. In recent years, the study was mainly concentrated in 2 aspects: the normal β-globin gene transfer and endogenous γ-globin re-activation. Some studies showed that the expression of miRNAs was dysregulated in β-thalassemia. Some miRNAs could regulate γ-globin at posttranscriptional level, thus, the clarification of relationship between miRNAs and β-thalassemia is expected to provide experimental bases to β-thalassemia therapy. In this review, the induced therapy of γ-globin for β-thalassemia and its relationship with the miRNA are summarized.
China ; Fetal Hemoglobin ; metabolism ; Genetic Therapy ; Humans ; MicroRNAs ; metabolism ; beta-Globins ; genetics ; beta-Thalassemia ; therapy ; gamma-Globins ; therapeutic use

OBJECTIVETo study the effect of liposomal transfection of antisense oligonucleotide (ASON) on the erythroid cell alpha-globin gene in the patients with severe beta-thalassemia, and provide a new idea for beta-thalassemia gene therapy.

METHODSA highly effective ASON targeting alpha-globin gene was transfected into severe beta-thalassemic erythroid cells cultured in vitro by liposomal at an optimal concentration. The expression level of alpha, beta, gamma-globin gene, the level of hemoglobin, and the excess alpha-globin chains precipitates in ASON group and control group were carefully analyzed by quantitative real-time PCR(Q-RT-PCR), high performance liquid chromatography (HPLC), and electron microscope, respectively.

RESULTSThe mRNA expression of alpha-globin gene was significantly lower in ASON group (9.04 +/- 0.29) than in control group (24.23 +/- 0.29) (P<0.01). Simultaneously, the disequilibrium between alpha- and beta-, gamma-globin gene expression was partly modified by ASON, the ratios of ASON group and control group being 0.79 +/- 0.02 and 2.26 +/- 0.06 respectively (P<0.01). HPLC demonstrated that the levels of HbA2 and HbF increased with downregulation of alpha-globin gene in beta-thalassemic erythroid cells, particularly HbF. The precipitates of alpha-globin chains in ASON group were lessened under electron microscope, particularly in early erythroblast while no change in the control group.

CONCLUSIONThe high effective ASON contributes to inhibit the alpha-globin gene expression of severe beta-thalassemic erythroid cells, partly modify the disequilibrium between alpha-, beta- and gamma-globin gene expression and obviously reduce the precipitates of alpha-globin chains in erythroid cells. It might provide a new idea for gene therapy of beta-thalassemia.

Cells, Cultured ; Child ; Genetic Therapy ; Humans ; Liposomes ; Oligonucleotides, Antisense ; genetics ; Transfection ; alpha-Globins ; genetics ; metabolism ; beta-Globins ; metabolism ; beta-Thalassemia ; genetics ; metabolism ; therapy ; gamma-Globins ; metabolism

OBJECTIVETo detect rare types of thalassemia mutations among southern Chinese population.

METHODSPeripheral blood samples from 327 patients from various regions of southern China were collected. The patients were suspected as rare-type thalassemia for their inconsistency between hematological phenotypes and results of routine mutation screening. The samples were further analyzed with GAP-PCR and DNA sequencing.

RESULTSOne hundred and eight cases were diagnosed as rare types of thalassemia. Among whom 10 rare α-globin gene mutations including --THAI, HKα, αααanti3.7, αααanti4.2, -α2.8, -α27.6, CD74 GAC>CAC (Hb Q-Thailand), CD30 (-GAG), CD31 AGG>AAG and CD118 (+TCA), and 12 rare &beta;-globin gene mutations including CD37 TGG>TAG, CD39 CAG>TAG/CD39 CAG>TAG, &beta; II-2 (-T), -90(C>T), -31(A>C), -88(C>T), CD7(-A), CD138(+T), CD89-93 (--AGTGAGCTGCACTG), CD54-58 (-TATGGGCAACCCT), Chinese G &gamma; +(A &gamma;&delta;&beta;)0 and Vietnamese HPFH (HPFH-6) were identified. -88(C>T) (HBB: c.-138C>T) and CD39 CAG>TAG (HBB: c.118C>T) were discovered for the first time in Chinese population. CD7(-A) (HBB: c.23delA) and CD138(+T) (HBB: c.416_417insT) were new types of &beta;-globin gene mutations.

CONCLUSIONThe present study have enriched the mutation spectrum of thalassemia in southern China, which has provided necessary information for its diagnosis.

Humans ; Mutation ; Thalassemia ; genetics ; alpha-Globins ; genetics ; beta-Globins ; genetics

OBJECTIVETo investigate the relationship of beta-thalassemia mutations and the single nucleotide polymorphism(SNP) at position -158 of (G)Gamma-globin gene to the altered levels of fetal hemoglobin(Hb F) of beta-thalassemia heterozygotes.

METHODSHb F was quantitated by alkali denaturation; beta-thalassemia mutations were determined by PCR-allelic specific oligonucleotide(PCR-ASO). The SNP at -158 was analyzed by amplification of (G)Gamma gene promoter fragments from the DNA, followed by Xmn I restriction enzyme digestion.

RESULTSAmong 63 cases with beta-thalassemia trait, 15 had Hb F levels above 2% (2.06%-10.44%). Six beta-thalassemia mutations were observed in this study, namely CD41/42(-TTCT), CD17(A-->T), nt28 (A-->G), CD71/72(+A), IVS-II-654(C-->T) and IVS-I-1(G-->T). There was no difference in the incidence of beta-thalassemia heterozygotes of CD41/42, CD17, CD71/72 and IVS-II-654 between 15 cases with Hb F>/=2% and 48 cases with Hb F<2%. Ten (15.9%) heterozygotes of (G)Gamma-158(C-->T)were detected among 63 cases, and 8 of them (53.33%) belonged to the group of Hb F>/=2% while the remaining 2 cases (4.17%) were in the group of Hb F<2%.

CONCLUSIONbeta-thalassemia mutations of CD41/42, CD17, CD71/72, IVS-II-654 had no influence on Hb F levels, but (G)Gamma-158(C-->T) had a strong association with moderately increased Hb F levels in beta-thalassemia heterozygotes in the Guangxi area of China.

Adult ; Female ; Fetal Hemoglobin ; genetics ; Heterozygote ; Humans ; Male ; Mutation ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide ; Pregnancy ; beta-Thalassemia ; genetics ; gamma-Globins ; genetics

This study was aimed to detect and identify the promoter CpG island methylation of &gamma;-globin gene in peripheral blood mononuclear cells from patients with &beta;-thalassemia major and healthy adult in Guangxi province, as well as to analyze the difference of promoter methylation rate of each CpG sites between them, and then to screen the promoter CpG island main methylation sites which maybe influence &gamma;-globin expression. The template DNA was modified by bisulfite genomic sequencing PCR; the promoter sequences of &gamma;-globin gene were amplified by technique Touchdown PCR, and then the PCR products were cloned and sequenced for obtaining methylation status of each CpG sites in target fragments, and then the accurate methylation sites and levels were detected quantitatively. The results indicated that the 4 CpG methylation sites locating at 28, 122, 231 and 234 bp in sequences were hypermethylated. As compared with healthy adults, the DNA methylation rate of 122 and 231 bp CpG sites in patients with &beta;-thalassemia major was obviously lower, however, methylation rates of 28 and 234 bp sites were not significantly different between patients and healthy adults. It is concluded that the methylation sites 28, 122, 231 and 234 bp of &gamma;-globin gene promoter are found both in patients with &beta;-thalassemia major and healthy adults. The 122 and 231 bp sites are identified preliminarily to be involved in the regulation of &gamma;-globin expression. This study provides the experimental evidence for alleviating the clinical symptoms of &beta;-thalassemia major and targeting gene treatment through the regulation of &gamma;-globin.
Adolescent ; Adult ; Case-Control Studies ; Child ; CpG Islands ; DNA Methylation ; Female ; Humans ; Male ; Promoter Regions, Genetic ; Young Adult ; beta-Thalassemia ; genetics ; gamma-Globins ; genetics

β-thalassaemias are inherited hemoglobin disorders caused by defects in the β-globin gene. In recent years, researches have re-mentioned the therapeutic significance of drug-induced fetal hemoglobin (HbF), which can reduce the imbalance of α and β chains and improve the severity of anemia by increasing the expression of γ chain. Drug trials, such as hydroxyurea, thalidomide and desitabine have shown elevated hemoglobin, decreased blood transfusion dependence, and reduced symptoms other than anemia after treatment. In addition, in vitro experiments suggested that HbF can also induce by other drugs, which providing important clues for safe and effective HbF inducers. Therefore, this article reviews the current research progress so as to expect beneficial to clinical treatment.
Blood Transfusion ; Fetal Hemoglobin ; Humans ; Hydroxyurea ; beta-Globins ; beta-Thalassemia

OBJECTIVETo evaluate the practical values of PCR detectable T-cell receptor (TCR) gene rearrangement in paraffin embedded tissue samples in the diagnosis of T-cell malignancies using BIOMED-2 PCR multiplex tubes TCRgamma(A+B).

METHODSTraditional phenol-chloroform method was used to extract DNA from 55 cases of archival paraffin embedded tissues samples of T-cell malignancies and the DNA quality was evaluated by PCR-based amplification of housekeeping gene beta-globin. The selected BIOMED-2 PCR multiplex tubes TCRgamma(A+B) were used to detect TCR gene rearrangement and comparison with the results of universal TCR primers (T(VG)/T(JX)) was performed.

RESULTSPositive detection rates by the BIOMED-2 multiplex tubes TCRgamma(A+B) and the universal primers (T(VG)/T(JX)) were 76.4% and 60.0%, respectively. There were not statistical difference between the methods (P > 0.05).

CONCLUSIONBIOMED-2 multiplex tubes TCRgamma(A+B) is suitable for detection of clonal rearrangements of TCR genes in current archival paraffin embedded tissue samples of T-cell malignancies.

DNA Primers ; DNA, Neoplasm ; analysis ; Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor ; Humans ; Lymphoma, T-Cell ; genetics ; metabolism ; pathology ; Paraffin Embedding ; Polymerase Chain Reaction ; methods ; beta-Globins ; metabolism

OBJECTIVES: Peripheral blood-buffy coat fractions (N = 14, 956) have been stored at -70degrees C in the headquarter of the Korean Multicenter Cancer Cohort (KMCC), since 1993. To study the future molecular etiology of cancers using specimens of the cohort, properly stored specimens are necessary. Therefore, the DNA-viability of the buffy coat samples was investigated. METHODS: Buffy coat fraction samples were randomly selected from various collection areas and years (N = 100). The DNA viability was evaluate from the UV-absorbent ratios at 260/280nm and the PCR for beta-globin was performed with genomic DNA isolated from the buffy coat. RESULTS: PCR products were obtained from 85 and 98% of the C and H area-samples, respectively, using 50 or 100mul of the buffy coat. There were significant differences in the yields of the PCR-amplifications from the C and H areas (p < 0.05), which was due to differences in the homogenization of the buffy coat fractions available as aliquots. The PCR-products were obtained from all of the samples (N = 7) stored at the C area-local center, but the other aliquots stored at the headquarter were not PCR-amplified. Therefore, the PCR products in almost all the samples, even including the DNA-degraded samples, were obtained. In addition, an improvement in the DNA isolation, i.e. approx. 1.6 fold, was found after using extra RBC lysis buffer. CONCLUSIONS: PCR products for beta-globin were obtained from nearly all of the samples. The regional differences in the PCR amplifications were thought to have originated from the different sample-preparation and homogenization performance. Therefore, the long term-stored buffy coat species at the KMCC can be used for future molecular studies.
beta-Globins ; Cohort Studies* ; DNA* ; Polymerase Chain Reaction

Globin gene induction therapy is a new treatment under study for &beta;-thalassemia. This review summarizes the research progress on the mechanisms of globin gene induction therapy for &beta;-thalassemia and current &gamma;-globin gene induction medicines.
Animals ; Genetic Therapy ; Globins ; genetics ; Humans ; beta-Thalassemia ; therapy