[Expression of MiR-144/451 in Different Types of Anemia].

OBJECTIVE: To investigate the expression level and clinical correlation of microRNA-144/451 gene cluster (miR-144/451) in different types of anemia. METHODS: The peripheral blood of patients with aplastic anemia (AA), myelodysplastic syndrome (MDS) and diffuse large B-cell lymphoma (DLBCL) who had been diagnosed with anemia for the first time and after chemotherapy were collected. The expression levels of miR-144 and miR-451 were measured by RT-qPCR, and the correlation between the expression levels of miR-144 and miR-451 and routine laboratory indexes was analyzed by Spearman correlation analysis. RESULTS: The expression levels of miR-144 and miR-451 in the peripheral blood of AA and MDS patients were significantly lower than those in normal controls (all P < 0.01). No statistical differences were observed in the expression level of miR-144 in three subgroups of DLBCL patients (P >0.05), while the expression level of miR-451 in peripheral blood of three subgroups of DLBCL patients were significantly higher than those in normal controls (all P < 0.05). Correlation analysis showed that the expression levels of miR-144 and miR-451 in AA patients were positively correlated with red blood cell distribution width-coefficient of variation (RDW-CV) (r =0.629, 0.574). There were no significant correlations between the expression levels of miR-144 and miR-451 and laboratory parameters in MDS and DLBCL patients. CONCLUSION: Different types of anemia disorders have varying levels of miR-144 and miR-451 expression, which is anticipated to develop into a secondary diagnostic and differential diagnostic indicator for clinical anemia diseases.

[Dynamic Changes of ROS and Nrf2-Related Factors During Erythroid Development].

OBJECTIVE: To investigate the changes and roles of reactive oxygen species (ROS) and nuclear factor erythroid 2-related factor 2 (Nrf2) related antioxidases during erythroid development. METHODS: Flow cytometry was used to detect the sensibility of peripheral red blood cells of wild-type mice to a strong oxidant hydrogen peroxide (H2O2). Erythroid cells from different developmental stages in bone marrow (BM) were obtained using fluorescence-activated cell sorter and the ROS levels were detected by flow cytometry. RT-qPCR was used to detect the changes of expression levels of Nrf2 and related antioxidases in erythroid cells from different developmental stages in BM. The ROS levels of the peripheral blood and BM nucleated erythrocytes in Nrf2 knockout mice were further examined. The expression level of Nrf2 in erythroid precursors isolated from 14.5 d embryonic liver of wild-type mice during differentiation and culture in vitro was detected. RESULTS: In the peripheral blood of wild-type mice, the ROS level of reticulocytes and mature erythrocytes treated with H2O2 increased about 4 times and 7 times, respectively (P<0.01). In BM erythrocytes, the ROS level gradually decreased as the cells matured (r=0.85), while the expression level of Nrf2 and its related anti-oxidative genes increased (r=0.99). The ROS levels in peripheral blood erythrocytes and BM nucleated erythrocytes of Nrf2 knockout mice were significantly increased compared with wild-type mice (P<0.01). The expression of Nrf2 increased during the early erythroid development after embryonic liver cell sorting (P<0.01). CONCLUSION: The expression levels of Nrf2 and its related factors vary during erythropoiesis. Nrf2 at physiological level plays an important antioxidant role during the erythroid development.

[Expression Levels of MiR-451 in Erythroid Differentiation and Its Correlation with Hematological Diseases].

OBJECTIVE: To investigate the expression of miR-451 during erythroid differentiation and its correlation with hematological diseases. METHODS: The expression of miR-451 in erythroid differentiation of mouse hematopoietic stem cells (derived from fetal liver) was analyzed by cell culture, flow cytometry, magnetic bead sorting and qRT-PCR. The expression of miR-451 during erythroid differentiation of mouse erythroid leukemia cells (MEL) was analyzed by cell culture and qRT-PCR. The expression of miR-451 in peripheral blood of mice was detected by qRT-PCR, and the expression of miR-451 in fetal liver (14.5 days) was analyzed by microarray. The nucleated erythroid cells from bone marrow of wild type (WT) mice and ß-thalassemia (ß-thal) mice were sorted by flow cytometry, and the levels of miR-451 and erythroid genes were detected by qRT-PCR. The expression of miR-451 in peripheral blood of patients with clinical hematological diseases was detected by qRT-PCR. RESULTS: During the differentiation of mouse hematopoietic stem cells (derived from fetal liver) and MEL cells, the expression levels of miR-451 increased gradually. Compared with WT mice, the expression levels of miR-451 in peripheral blood, 14.5-day fetal liver cells and nucleated erythroid cells (sorted from bone marrow) of ß-thal mice were significantly increased(P<0.05). Many erythroid differentiation genes in nucleated erythroid cells (sorted from bone marrow) of ß-thal mice decreased. Compared with healthy controls, the expression levels of miR-451 was increased in peripheral blood of patients with ß-thalassemia and iron deficiency anemia, while the expression levels of miR-451 was decreased in patients with aplastic anemia and myelodysplastic syndrome. CONCLUSION: During erythroid differentiation, the expression levels of miR-451 increases gradually. In hematological diseases, the expression levels of miR-451 is different from that of normal controls, which is expected to become an auxiliary diagnostic index for clinical hematological diseases.

[New Advane of Reaserch on Relationship between Long Noncoding RNA and Acute Myeloid Leukemia--Review].

Acute myeloid leukemia（AML）is a myelopoietic stem/progenitor malignant disease. The exact etiology of this leukemia remains unclear, thus it is important to explore the pathogenesis of AML and to discover the new diagnostic markers and therapeutic targets. The long non coding RNA (lnc RNA) is a class of RNA molecules with transcripts over 200 nucleotides in eukaryotic cells which almost don't possess the ability to code proteins, but can regulate the expression of other genes at transcriptional and post-transcriptional levels, thereby participate in occurrence and development of varied tumors. Of late years, along with the deepening of study, the lncRNA roles played in the AML have been reported and confirmed. In this review, the relationships between the IncRNA (UCA1, ANRIL, H19, HOTAIR, CCAT1, ZFAS1, LINC00152, HOXA-A52, NEAT1, TUG1, IRAIN1, PANDAR, LINC00899, SNHG5, and KCNQ1OT1) and AML is summarized briefly, so as to provide the potential basis for the clinical diagnosis and therapy of AML.

[Research on Ralation of Long Non-coding RNA with Diffuse Large B-cell Lymphomas -Review].

Diffuse large B-cell lymphoma (DLBCL) accounts for approximately 30% of the non-Hodgkin's lymphoma patients. The underlying molecular mechanism of its pathogenesis is not well defined and the survival rate of DLBCL patients is very low. Moreover, the annual incidence and mortality of DLBCL is still rising. Accordingly, identification and characterization of new molecular pathways of DLBCL will lead to the development of novel diagnostic markers and molecular therapeutic targets. Long non-coding RNAs (LncRNA) are non-coding RNAs with a length greater than 200 bp in eukaryotic cells, which can regulate the expression of their target genes at the transcriptional and post transcriptional levels. The function of LncRNAs is involved in the initiation, progression, invasion and metastasis of many cancers. Recently, the role of LncRNAs in DLBCL has been identified and intensely studied. This review summarizes the recent discoveries in the expression and function of LncRNAs including HULC,PEG10,LincRNA-p21,HOTAIR,LUNAR1,MALAT1 and SubSigLnc-17 in DLBCL, so as to find potential diagnostic biomarkers and therapeutic targets for DLBCL.

[Transcription Factor Pax5 Promotes B-lymphomagenesis in a Promoter-Independent Manner].

OBJECTIVE: To determine whether B lymphocyte-specific transcription factor Pax5 regulates B-lympho-magenesis without direct binding to promoter. METHODS: Mouse B-lymphoma cell line myc3 and 38B9 were infected with GFP- tagged retrovirus that encodes wide type or various mutant pax5 genes. After viral infection for 48 hours, the percentage of GFP positive lymphoma cells was determined by flow cytomety. The percentage of GFP positive tumor cells was further monitored every 3 days in vitro or once the tumor was formed in vivo. Both cell cycle and apoptic cell number of GFP positive lymphoma cells were analyzed using flow cytometry. RESULTS: Similar to the infection with wild type Pax5 retrovirus, infection with Pax5 mt 1-357 and Pax5 mt 304-358 that lacks of DNA binding motif can strongly increase the percentage of GFP+ B-lymphoma cells both in vitro and in vivo (P<0.01), while infection with empty viral vector migR-GFP and Pax5 mt 1-143 containing only DNA binding motif failed to increase the percentage of GFP positive tumor cells (P>0.05). Moreover, the analysis of flow cytometry demonstrated that more B-lymphoma cells infected with wild type Pax5, Pax5 mt 1-357 and Pax5 mt 304-358 retroviruses entered S and G2/M phases in comparison with those infected with empty viral vector migR-GFP and Pax5 mt 1-143. Apoptotic rates among different groups were not significantly changed. CONCLUSION: Pax5 can promote B-lymphoma cell growth both in vitro and in vivo in a promoter-independent manner. This is mainly due to the accelerating of cell cycle rather than decreasing apoptosis. Our studies provide potential theory for restraing B-lymphomagenesis by targeting the specific Pax5 domains.

[γ-Globin Inductive Therapy of ß-thalassemia and Its Relationship with MicroRNA].

ß-thalassemia is a chronic hemolytic anemia characterized by the reduction or absence of synthesis of ß-globin chains because of the ß-globin gene mutations. ß-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 ß-globin gene transfer and endogenous γ-globin re-activation. Some studies showed that the expression of miRNAs was dysregulated in ß-thalassemia. Some miRNAs could regulate γ-globin at posttranscriptional level, thus, the clarification of relationship between miRNAs and ß-thalassemia is expected to provide experimental bases to ß-thalassemia therapy. In this review, the induced therapy of γ-globin for ß-thalassemia and its relationship with the miRNA are summarized.