MicroRNAs as Potential Markers Involved in Erythroid Differentiation: A Systematic Literature Review

: As a family of small non-coding RNAs, microRNAs (miRNAs) negatively modulate gene expression via directly targeting mRNAs in a sequence-specific pattern. Accumulated evidences have indicated that miRNAs involved in erythroid differentiation. Some experimental systems used for study the association of miRNAs with erythroid differentiation: 1) embryonic stem cells (hESCs) forced to erythropoiesis, 2) hematopoietic progenitor cells and erythroid-like cell lines induced to erythropoiesis by hypoxia and chemical substances, 3) and in vivo mice, zebrafish embryo systems. Based on the literatures, miR-451, miR-144, miR-486, miR-126-3p, miR-107, miR-199b-5p, miR-362, miR-188, miR-210, miR-125a, miR-146b, miR-22, miR-23a / miR-27a / miR-24, miR-16-2, miR-34a exhibit promotion role in erythropoiesis, while, miR-218, miR-320a, miR-221 / 222, miR-433, miR-200a, miR-223, miR-150, miR-34a-5p, miR-124, miR-Let-7d, miR-376a, miR-155, miR-126 / 126*, miR-103, miR-15a, miR-30a-5p, miR-26a-5p, miR-669m, miR-9 show suppression role in erythropoiesis. Nonetheless, the clear functional role of miR-24 is controversial in erythropoiesis. This article summarized the relationships between miRNAs and erythroid differentiation as well as potential target genes and action mechanisms. These discovered erythroid associated miRNAs stand for the starting point to develop novel approaches for miRNA treatment, miRNAs to be used as novel potential biomarker and target for diagnosis, therapeutics, prognosis of certain blood diseases, leading to promising prospects in blood diseases therapeutics.


Introduction
microRNAs (miRNAs) are about 22 nucleotides endogenous small non-coding RNAs that negatively modulate gene expression by directly inhibiting protein translation or degrading mRNA via directly binding to the 3′-UTR of targeted mRNAs [1,2]. A miRNA can bind to one or more mRNAs, about 30% of protein coding genes are known widely modulated by miRNAs. Its involved in cell differentiation, development, progression, apoptosis, proliferation, metastasis, chemoresistance and metabolism of crucial biological processes [3]. Specially, miRNAs are also functioning as tumor inhibitor or promoter in tumorigenesis [4,5]. Meanwhile, miRNAs play critical roles in accurate modulation regulation of stem cells start differentiating process which is vital for prevention and therapy of hematologic disorders [6]. Increasing evidences demonstrated miRNAs can modulate hematopoiesis and a number of miRNAs are specific for hematopoietic lineages. miRNA can potentially be clinical diagnostic and therapy biomarker because it has a high stability to describe biological change [7].
Hematopoiesis is a highly and precisely regulated multistage process which erythroid cells, lymphocytes and myeloid cells are originated from pluripotent stem cell [8]. Normal erythropoiesis produces about 10 11 new red blood cells (RBCs) in adult human every day through the commitment of hematopoietic stem cells into erythroid progenitors, subsequently differentiate into mature RBCs, RBCs are responsible for providing oxygen to the growing fetal, embryonic, adult tissues, maintaining blood viscosity and offering the shear stress which required for vascular remodeling and development [9]. The individual is in danger for serious pathological states containing thrombocytopenia and anemia when this normal erythropoiesis process is destroyed. On account of this rapid turnover in circulating blood cells, the hematopoietic system is poised to continuously supplement these lineages via differentiation, proliferation and maturation of immature progenitor populations.
Erythropoiesis is a multi-step cellular process by which a primitive multipotent hematopoietic stem cell (HSC) experiences a series of differentiations resulting in production of erythroid lineage, undergoing erythroid progenitors (colony-forming unit erythroid [CFU-E] and burst-forming unit erythroid [BFU-E]), normoblasts, proerythroblasts, early basophilic erythroblasts, late basophilic erythroblasts, polychromatic erythroblasts, orthochromatic erythroblasts, reticulocytes, ultimately differentiating to mature erythrocytes. The dynamic process is mediated by the balance of intrinsic and extrinsic factors, containing transcription factors, growth factors and miRNAs [10]. miRNAs are greatly associated with erythroid differentiation, regulating maturation of erythroid cells and transcription of globin genes [11].
A variety of testing systems can be applied to study the association of miRNAs with erythropoiesis, containing human embryonic stem cells (hESCs) forced to erythropoiesis, erythroid-like cell lines K562, TF-1, HEL, MEL, UT-7, KCL-22, MDS-L cells induced to erythropoiesis by hypoxia and chemical substances, erythropoietin (EPO)-induced CD34+ cells, CD133+ undergo erythroid differentiation which from hematological disease patients or normal healthy subjects, and in vivo systems, for example mice, zebrafish embryo.
The primary-miRNA (pri-miRNA) is synthesised in nucleus by RNA polymerase II, DiGeorge syndrome critical region 8 (DGCRB) and Drosha to cleave the pri-miRNAs, releasing precursor miRNA (pre-miRNA), which is carried to cytoplasm by GTP-bound Ran (RanGTP) and exportin-5 [12]. Following dicer cleaved pre-miRNA into about 22 nucleotide functional mature miRNA, then mature miRNA assembled into the Argonaute2 (Ago2) to form RISC [13]. Subsequently, the miRNA regulated erythroid differentiation by inhibiting translation via directly binding to the 3′-UTR of targeted mRNA ( Figure 1). To date, dozens of miRNAs have been identified to be associated with erythroid differentiation, these discovered erythroid associated-miRNAs on behalf of the starting point to develop novel approaches for miRNA treatment, based on miRNA silencing or miRNA replacement. This article summarized the relationships between miRNAs and erythroid differentiation, as well as potential action mechanisms in recent years. The study obtained on it has led to a new interest in underlying role and mechanism of miRNAs dysexpression in erythroid differentiation, which might potentially offer new insight of miRNAs deregulation in erythroid differentiation study. We believe that understanding the roles of miRNAs involved in erythroid differentiation would offer new viewpoint for developing novel diagnostic markers and treatment reagents and of certain blood diseases. Figure 1. The biosynthesis of miRNA and its regulatory mechanism on erythroid differentiation. The pri-miRNA is synthesised in nucleus by RNA polymerase II, then pri-miRNAs are cleaved by Drosha and DGCRB, and releasing pre-miRNA, which is carried to cytoplasm by exportin-5 and RanGTP. Once the pre-miRNA reaches the cytoplasm, Dicer cleaves it into nearly a 22 nucleotide long functional mature double-stranded miRNA, which then assembles into the Ago2 protein to form RISC. Following the miRNA regulates erythroid differentiation by suppressing protein translation via binding to the 3′-UTR of targeted mRNA.

miR-144 / miR-451
miR-144 / miR-451 are co-transcribed miRNAs, many literatures reported miR-144 / 451 were closely related with erythroid differentiation. miR-451 was upregulated 270-fold during erythropoiesis of purified normal human erythroid progenitors, and the expression level of miR-451 in red blood cells was approximately 10000-fold higher than in granulocytes, suggesting miR-451 was key molecule for normal erythropoiesis [14]. Meanwhile, miR-451 was also increased during thalassemic peripheral blood CD34+ cell erythroid differentiation of erythroid progenitors [15]. In contrast, miR-451 showed no transient up-regulation in erythroid cells derived from extravascular hemolytic anemia, hereditary spherocytosis patients [15]. The results indicating there are existed a dysexpressed miR-451 expression pattern in early erythroid progenitors of β-thalassemia, and analysis the differential expression of miRNAs is a significative method to confirm the abnormity of erythroid differentiation. This method may be used as a novel tactics of gene therapy for hemoglobinopathies, for example sickle cell anemia and β-thalassemias. miR-144 / 451 is necessary for erythroid homeostasis which were highly expressed during erythrocyte development. Mice with miR-144 / 451 ablation deletion exhibit a cell autonomous impairment of late erythroblast maturation, resulting in splenomegaly, erythroid hyperplasia and mild anemia [16]. Mice with miR-144 / 451 deletion also caused erythrocyte instability and increased sensibility to injure after exposure to oxidant drugs. The phenotype was profoundly conserved, as miR-451 knockdown cooperates with oxidant stress lead to significant anemia in zebrafish embryos [17]. miR-451 could directly suppress 14-3-3ζ expression, which inhibited nuclear aggregation of FoxO3 (a positive modulator of erythroid anti-oxidant genes). Hence, the accumulation of14-3-3ζ caused partial relocalization of FoxO3 from cell nucleus to cytoplasm by inhibiting its transcriptional process in erythroblasts with miR-144 / 451 -/ -. Meanwhile, 14-3-3ζ overexpression inhibited cell nuclear localization and activity of FoxO3 in erythroid cells and fibroblasts. Furthermore, 14-3-3ζ knockdown protected miR-144 / 451 -/erythrocytes from peroxide-caused damage and restored catalase activity. The results demonstrated that miR-144 / 451 protects erythrocytes from oxidant stress via inhibiting 14-3-3ζ [17].
This study found a new miRNA-mediated network that protects erythrocytes from oxidant stress which might be regarded as new therapeutic methods directed at decreasing oxidative stress, a main issue in sickle cell anemia and thalassemia.
As a target of both miR-144 and miR-451, RAB14 negatively modulated human erythropoiesis, RAB14 overexpression counteracted the inhibitory action of miR-144 and miR-451 knockdown on erythropoiesis of TF1 cells, meanwhile, its knockdown rescued the inhibitory action of miR-144 and miR-451 depletion on erythropoiesis of TF1 cells. The results indicated that miR-144 / miR-451 via directly binding to RAB14 to regulate erythroid differentiation [18]. Furthermore, the leukemogenic RUNX1 / ETO (Runt Related Transcription Factor 1 / Myeloid translocation gene on chromosome 16) fusion protein emerged as a critical modulator of miRNA network, promoting differentiation at erythroid / megakaryocytic junction point, which could transcriptionally repress miR144 / 451 expression [23]. Moreover, miR-451 played an important role in facilitating erythroid maturation of zebrafish partially by directly targeting GATA2 (globin transcription factor 2) [24].

miR-486, miR-126-3p
Hydroquinone (HQ) could inhibit erythropoiesis in a dose-dependent fashion. The expression levels of miR-486 and miR-126-3p were markedly decreased in CD34+ cells after treatment with HQ compared to untreated CD34+ cells by miRNA microarray analysis. miR-486 overexpression promoted erythroid differentiation of K562 cells and weaked the inhibitory effects on HQ-treated K562 cells erythroid differentiation. In addition, miR-486-5p expression level was negatively associated with the concentration of benzene inhalation on erythroid cell toxicity of C57BL / 6J mice. Especially, miR-486 downregulation occurred in male patients of chronic benzene poisoning [21]. The inhibition of miR-486 might be related with benzene-caused perturbation of erythropoiesis.
Further research found that miR-486 was markedly overexpressed in chronic myeloid leukemia (CML) than in CD34+ cells, especially in erythroid-megakaryocyte progenitor population and its expression was the highest in peripheral blood cells, meanwhile, miR-486 was increased during EPO-or GM-induced CD34+ cells erythroid differentiation [25,26]. The overexpression / inhibition of miR-486 promoted / inhibited erythropoiesis and proliferation of CD34+ cells [25]. Meanwhile, the expression level of miR-486 rapidly increased in hypoxia-induced TF-1 cells, its overexpression / inhibition promoted / suppressed TF-1 cells erythroid differentiation and proliferation. Furthermore, Sirt1 was a target gene of miR-486 which could modulate hypoxia-induced erythroid differentiation. Mechanically, miR-486 could regulate the TF-1 cells erythropoiesis and proliferation abilities by directly targeting Sirt1 [27]. The results unveiled a novel biological regulation mechanism for miRNA-regulated gene transcription in connecting hypoxia to erythropoiesis of hematopoietic cells.

miR-362, miR-210 and miR-188
miR-362, miR-210 and miR-188 play crucial role in erythropoiesis. miR-362, miR-210 and miR-188 were lowly expressed in GM-CSF-dependent UT-7 / GM cells compared to EPO-dependent UT-7 / EPO cells, moreover, the expression levels of miR-362, miR-210 and miR-188 were increased in EPO-treated UT-7 cells compared with GM-CSF-treated UT-7 cells [28]. miR-210 expression was 2-fold lower in TER-119-negative cells (TER-119 is an erythroid-specific antigen) than in TER-119-positive cells, and miR-210 expression level was significantly increased during erythroid saturation [28,29]. miR-210 exhibiting different expression levels in erythroid precursor cells from one normal and two thalassemic patients expressing different levels of fetal hemoglobin, and miR-210 was highly expressed in erythroid precursor cells derived from hereditary persistence of fetal hemoglobin (HPFH) patients. Moreover, the expression level of miR-210 was increased in a dose-and time-dependent manner during erythroid differentiation of mithramycin (MTH)-induced K562 cells and EPO-induced erythroid precursor cells, and suppression of miR-210 significantly inhibited MTH-induced K562 cells erythroid differentiation [30]. PLCβ1 is a critical molecule in nuclear inositide signaling, which associates with cell cycle progression, differentiation and proliferation, PLCβ1 could regulate erythroid differentiation via miR-210. PLCβ1 overexpression resulted in decrease of miR-210 expression in K562 cells after treatment with MTH, vice versa, PLCβ1 knockdown increased the expression level of miR-210, suggesting PLCβ1 inhibited MTH-induced K562 cell erythropoiesis by inhibiting miR-210 expression [31]. Furthermore, miR-210 was also overexpressed in hypoxia-induced K562 and CD34+ cells erythroid differentiation, meanwhile, miR-210 silencing inhibited globin gene expression and retarded maturation of CD34+ and K562 cells [32], suggesting miR-210 promoted hypoxia-induced erythropoiesis and the process was partially regulated by miR-210.

miR-107, miR-181a
miR-107 exhibited low expression in KCL-22 and K562 cells, the overexpression of miR-107 promoted sodium butyrate-induced erythroid differentiation of KCL-22 and K562 cells, while no effect on KCL-22 and K562 cells proliferation. Meanwhile, miR-107 promoted erythroid differentiation of KCL-22 and K562 cells by directly targeting Cacna2d1 [33], offering potential therapeutic methods for CML patients. miR-181a expression was also markedly downregulated in CML patients and K562 cells. Furthermore, miR-181a could promote the hemin-treated erythroid differentiation of K562 cells [34]. However, the potential mechanism of miR-181a on erythropoiesis is uncover.

miR-125a
miR-125a was overexpressed in bone marrow (BM) CD34+ cells of myelodysplastic syndromes (MDS) patients compared to BM CD34+ cells from healthy donors, the expression level of miR-125a negatively correlated with MDS patient survival, meanwhile, miR-125a overexpression inhibited erythropoiesis of Ara-C-induced K562 and MyD88-induced MDS-L cells [36]. miR-125a might use as a potential therapeutic target and prognostic biomarker in MDS.

miR-22
miR-22 could control the balance of megakaryocyte and erythroid differentiation from their common precursor. Megakaryopoiesis was promoted in miR-22 knockout mices after infection with lymphochoriomeningitis (LCMV) virus, whereas erythropoiesis was destroyed [38]. The result provided in vivo evidence that miR-22 played a crucial role in modulating erythropoiesis during infectious stress.
Additional, miR-23a / miR-27a also positively regulated the expression of β-like globin gene by directly binding to KLF3 (krupple like factor 3) and SP1 (stimulatory protein 1) in K562 and CD34+ cells. Interestingly, miR-23a / miR-27a enhanced the transcription of β-like globin gene by inhibiting KLF3 and SP1 binding to the gene locus of β-like globin during erythropoiesis. Furthermore, KLF3 could suppress the expression of miR-23a27a24-2 cluster (named as miR-23a cluster) by binding to the CACCC sites in the promoter of miR-23a cluster, miR-23a cluster and KLF3 formed a positive feedback loop to promote β-like globin expression during erythropoiesis [40]. Meanwhile, miR-27a promotes hemin-induced erythroid differentiation of K562 cells by targeting CDC25B [41].

miR-218
miR-218 targeted and inhibited ALAS2 (delta-aminolevulinate synthase 2) expression through directly targeting to its 3′-UTR. miR-218 overexpression significantly changed iron metabolism and suppressed hemin-induced erythroid differentiation of K562 cells, which consistent with the effect of ALAS2 silencing in K562 cells [45]. Taken together, miR-218 changed iron metabolism and suppressed inhibited erythropoiesis via directly targeting ALAS2. Akap7 and Xk are possibly responsible for the miR-669m-induced erythropoiesis impairment [62] miR-9 G1ER, fetal liver-derived erythroblasts, mice miR-9 was highly expressed in mature myeloid cells but at relatively low levels in erythroid cells; miR-9 overexpression inhibited differentiation with an increase in reactive oxygen species (ROS) production in vitro and in vivo.

miR-223
miR-223 was down-regulated in CD34+ cells, whereas LMO2 (LIM domain only 2), a crucial molecule for erythropoiesis, was overexpressed. miR-223 overexpression reduced the expression level of LMO2 by binding to 3'-UTR-LMO2, and impaired the EPO-induced erythroid differentiation and erythroid colony formation of CD34+ cells [52]. Accordingly, knockdown of LMO2 mimics the action of miR-223 overexpression [52]. Meanwhile, miR-223 expression was decreased during erythroid differentiation of hemin-induced K562 cells, miR-223 overexpression significantly decreased γ-globin expression and benzidine-positive K562 cells, further indicating an inhibitory role of miR-223 on erythropoiesis [53]. Mechanically, miR-223 negatively regulated erythropoiesis of K562 cells through downregulating LMO2 expression, and miR-223 downregulation was necessary for erythroid progenitor recruitment and commitment that results in extension of erythroblast cells at least partially regulated by promoting LMO2 expression.

miR-124, miR-Let-7d
miR-124 was decreased during cells erythroid differentiation of EPO-induced CD34+ and hemin-induced K562, and miR-124 inhibited erythropoiesis via directly targeting c-MYB and TAL1. Meanwhile, miR-124 also inversely regulated erythroid differentiation in xenograft mice. miRNA biosynthesis is precisely controlled by post-transcriptional mediators, containing RBPs, QKI5 (quaking 5), an RBP, could activate the primary miR-124-1 biosynthesis processing during erythroid differentiation. QKI5 recognized a distal QKI response element and interacted with DGCR8 to recruit microprocessor, then the recruited microprocessor was taken to primary miR-124-1 stem loops by a spatial RNA-RNA interaction. As erythropoiesis proceeds, the accompanying reduce of QKI5 released microprocessor from primary miR-124-1 and reduced mature miR-124 expression to accelerate maturation of erythrocytes [56]. The results demonstrated the crucial effect of QKI5 in miRNA biosynthesis processing during erythroid differentiation.

miR-9
miR-9 was overexpressed in acute leukemia, and it was highly expressed in mature myeloid cells but at relatively lower level in erythroid cells. Meanwhile, miR-9 overexpression inhibited erythroid differentiation of G1ER cells and fetal liver-derived erythroblasts in vitro. Furthermore, miR-9 overexpression blocked erythroid differentiation in vivo. Interestingly, miR-9 overexpression significantly blocks erythroid progenitor cells differentiation with an increase in reactive oxygen species (ROS) production. Mechanistically, miR-9 blocks erythropoiesis by deregulating FoxO3-mediated pathways, which may contribute to the ineffective erythropoiesis observed in patients with hematological malignancies [64].

Paradoxical Roles of miR-24 in Erythroid Differentiation
miR-24 is the second miRNA whose function involved in erythropoiesis was illuminated, however, the potential exact role of miR-24 is controversial, as summarized in Table 3. miR-24 directly interfered with activin signaling by directly targeting ALK4-3′-UTR (anaplastic lymphoma kinase 4, activin type I receptor) and decreasing the expression of ALK4, thus weaken activin-induced erythroid differentiation of CD34+ and K562 cells. Meanwhile, miR-24 expression was negatively associated with ALK4 during erythroid differentiation, this finding demonstrated a modulation style of miR-24 on erythroid differentiation via inhibiting ALK4 expression. The data indicated miR-24 negatively modulates erythroid differentiation through regulating the activin signaling pathway [65].
However, far from the inhibition role of miR-24 in erythroid differentiation, one research presented exactly opposite data and perspectives, the expression of miR-24 increased during erythropoiesis of EPO-induced CD34+ and hemin-induced K562 cells, furthermore, miR-24 promoted erythroid differentiation by directly targeting Sp1 via increasing the expression of γ-globin and ε-globin [66]. We think the conflict results might come from the different inducer. The exact functional role of miR-24 involved in erythropoiesis need further confirmation and the in vivo function still need to investigated to better comprehend the biological significance of miR-24.

Conclusions
Hematopoiesis is a accurately regulated multi-step process including HSCs self-renew and hematopoietic stem / progenitor cells differentiation. How HSCs undergo linage commitment and evolve into a variety of mature blood cells has been a hotspot for many years [7][8][9]. There are now strong evidences that miRNAs are important regulators of hematopoiesis, which could regulate hematopoietic commitment, differentiation, apoptosis and proliferation of hematopoietic cells. miRNAs represent a family of non-coding small RNAs, which are capable of causing mRNA degradation, inhibiting protein translation and modulating various crucial cellular processes, containing cell differentiation, metastasis, proliferation, chemoresistance [1,2]. About 3000 recognized miRNAs exist in species ranging from humans to plants, indicating a common evolutionary mechanism of mediation gene expression. According to our summary and analysis, the targets and integrated underlying mechanisms of miRNAs involved in erythroid differentiation were hypothesized and illustrated in Figure 2 and Figure 3.  miRNAs considered as potential targets for cancer and blood diseases therapy. Gain-and loss-of function experiments will provide a better thought about the clinical application of miRNAs. The find of miRNAs which involved in blood disorders has two vital significances: the first is the development of novel diagnostic and prognostic tools, the second is the development of new therapies. miRNA-based therapies bring a goodly prospect, particularly in the area of oncology research, in vivo to inhibit miRNA function provide new exciting opportunities for treatment. There are two ways about miRNA-based therapies: miRNA replacement and miRNA silencing. In miRNA silencing therapy, single-stranded locked nucleic acid (anti-miRNA) bind to miRNA complementarily, preventing the miRNA from binding to target mRNAs [3,6]. In miRNA replacement therapy, miRNA is reintroduced using a miRNA mimic, these double-stranded miRNA mimics can either be packaged in nanoparticles to enhance their stability or modified on the complementary strand [3,6]. The transportation of miRNA mimics and anti-miRNA can be boosted with nanoparticles conjugated to antibodies or cancer-specific ligands [3,6]. Although miRNA antagonists and mimics are capable of imitating and silencing, these mimics or antagomirs have not yet been used to therapy certain blood diseases in clinical trials. The intriguing method is expected to bring crucial creative tactics in blood disorders. With respect to miRNA-based clinical experiments, only NCT01108159 was used in the field of hematological to discover changed mRNA / miRNA expression which involved in the development, progression and therapeutic response of hematological diseases. In spite of there are remain a variety of challenges to conquer before miRNA therapeutics can be used clinically, it is predicted that in the near future, miRNA-based therapeutics may offer significant progress in hematologic disorders. Further researches are needed to find more target molecules of miRNA and obtain a better comprehending of the underlying action mechanisms of miRNA involved in erythroid differentiation.
Taken together, the study on the function role of miRNAs in erythropoiesis has significant underlying value not only for comprehending blood diseases development and progression, but also for searching new diagnostic and therapeutic methods. Although we have learned more about the function of miRNAs in production of erythrocytes, the physiological and biological function role of these miRNAs still immensely mysterious, because of a variety of studies were investigated in passage cells instead of primary cells. Even though passage cells are readily obtainable and can be easily operated, there are a lot of examples where phenotypes observed in vitro contrast with those observed when molecules are mutated in vivo. In view of this, more researches should to be concentrated on the animal models for the coincident and dependable results which will enable us to thoroughly understand the pathobiology of erythropoiesis in the future. A better understanding of important regulator miRNAs of erythroid differentiation may provide novel choices for developing more effective therapeutic method for human blood diseases. We hope the current work will offer an up-to-date references for the most recent progresses in erythroid differentiation study of miRNA.

Summary and Perspective
An in-depth understanding the molecular mechanisms of erythropoiesis is exceedingly crucial for not only generating abundant amounts of erythroid cells in vitro or ex vivo for transplantation and therapeutics (which will possibly overcome present obstacles in the fields of bulk RBC production due to the lack of blood donor resources and high costs), but also for offering the chance to mediate the pathological dyserythropoiesis. During the last decade, efficient technology to produce RBC ex vivo using primary HSCs, embryonic stem cells or induced pluripotent stem cells, have become an increasing. Certain miRNAs are related with the erythropoiesis. The correlation of miRNAs related to erythropoiesis as well as its detailed underlying molecular mechanism, need to be explored. We expect some miRNAs to be used as underlying biomarkers and targets for diagnosis and therapy of some blood diseases, leading to promising prospects in blood diseases therapy.