Dysregulation of miR-124-1 predicts favorable prognosis in acute myeloid leukemia

LncRNA MAFG-AS1-induced acute myeloid leukemia development via modulating miR-147b/HOXA9

Recent references discovered that lncRNAs acted roles in malignant cancer development. However, the role of MAFG-AS1 in acute myeloid leukemia (AML) development remains unknown. MAFG-AS1 and miR-147b were determined in AML cells and specimens using qRT-PCR assay. Cell proliferation was detected by CCK-8 analysis and flow cytometry was carried out to measure cell cycle. Luciferase reporter analysis was done to determine the mechanism of MAFG-AS1 and miR-147b. We noted that MAFG-AS1 was overexpressed in AML cells and in serum and bone narrow from AML compared with normal controls specimen. Elevated expression of MAFG-AS1 increased cell growth, cycle and EMT in AML cell HL-60 cell. MAFG-AS1 sponged miR-147b expression in HL-60 cell. Moreover, miR-147b was downregulated in AML cells and in serum and bone narrow from AML compared with normal control specimen. miR-147b was negatively correlated with MAFG-AS1 in the serum and bone narrow of AML cases. We illustrated that HOXA9 was one target of miR-147b and ectopic expression of MAFG-AS1 enhanced HOXA9 expression HL-60 cell. Forced expression of MAFG-AS1 induced cell growth, cycle, and EMT via promoting HOXA9. These data illustrated that MAFG-AS1 acted as one oncogenic gene and accelerated AML progression via modulating miR-147b/HOXA9 axis.

Distinct association of RUNX family expression with genetic alterations and clinical outcome in acute myeloid leukemia

BACKGROUND

The runt-related transcription factor family (RUNXs) including RUNX1, RUNX2, and RUNX3 are key transcriptional regulators in normal hematopoiesis. RUNXs dysregulations caused by aberrant expression or mutation are frequently seen in various human cancers especially in acute myeloid leukemia (AML).

OBJECTIVE

We systemically analyzed the expression of RUNXs and their relationship with clinic-pathological features and prognosis in AML patients.

METHODS

Expression of RUNXs was analyzed between AML patients and normal controls from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) projects. Correlations between RUNXs expression and clinical features together with survival were further analyzed.

RESULTS

All RUNXs expression in AML patients was significantly increased as compared with controls. RUNXs expression was found to be significantly associated with genetic abnormalities such as RUNX1 mutation, t(8;21) and inv(16)/t(16;16). By Kaplan-Meier analysis, only RUNX3 overexpression was associated with shorter overall survival (OS) and disease-free survival (DFS) among non-M3 AML patients. Notably, in high RUNX3 expression groups, patients received hematopoietic stem cell transplantation (HSCT) had markedly better OS and DFS than patients without HSCT among both all AML and non-M3 AML. In low RUNX3 expression groups, there were no significant differences in OS and DFS between HSCT and non-HSCT groups among both all AML and non-M3 AML. In addition, a total of 835 differentially expressed genes and 69 differentially expressed microRNAs were identified to be correlated with RUNX3 expression in AML.

CONCLUSION

RUNXs overexpression was a frequent event in AML, and was closely associated with diverse genetic alterations. Moreover, RUNX3 expression may be associated with clinical outcome, and helpful for guiding treatment choice between HSCT and chemotherapy in AML.

The Role of MiR-124 in Bladder Cancer – A Review of the Literature

MicroRNAs (miRNAs) are a group of non-coding RNA molecules that have an important role in modulating the expression of genes involved in regulating cellular functions. A growing number of studies suggest the abnormal expression of microRNAs in different types of cancer cells. MiRNA-124 is a microRNA that is down-regulated in many types of cancer cells, including bladder cancer. Our objective is to provide a review of the key publications that studied the effect of miR-124 on bladder cancer. This review focus on the targets and different pathways of miR-124 that were identified in various studies and differences between their expressions in normal urothelium and tumor tissues. We also include data regarding urinary methylations levels of miR-124 and their role in bladder cancer diagnosis and prognosis. Subsequently, we establish future perspectives of miR-124 research and its promising role in bladder cancer.

MicroRNAs Associated With a Good Prognosis of Acute Myeloid Leukemia and Their Effect on Macrophage Polarization

Acute myeloid leukemia (AML) is an aggressive myeloid malignancy with poor outcomes despite very intensive therapeutic approaches. For the majority of patients which are unfit and treated less intensively, the prognosis is even worse. There has been unspectacular progress in outcome improvement over the last decades and the development of new approaches is of tremendous interest. The tumor microenvironment is credited with an important role in supporting cancer growth, including leukemogenesis. Macrophages are part of the tumor microenvironment and their contribution in this setting is increasingly being deciphered, these cells being credited with a tumor supporting role. Data on macrophage role and polarization in leukemia is scarce. MicroRNAs (miRNAs) have a role in the post-transcriptional regulation of gene expression, by impending translation and promoting degradation of messenger RNAs. They are important modulators of cellular pathways, playing major roles in normal hematopoietic differentiation. miRNA expression is significantly correlated with the prognosis of hematopoietic malignancies, including AML. Oncogenic miRNAs correlate with poor prognosis, while tumor suppressor miRNAs, which inhibit the expression of proto-oncogenes, are correlated with a favorable prognosis. miRNAs are proposed as biomarkers for diagnosis and prognosis and are regarded as therapeutic approaches in many cancers, including AML. miRNAs with epigenetic or modulatory activity, as well as with synergistic activity with chemotherapeutic agents, proved to be promising therapeutic targets in experimental, pre-clinical approaches. The clinical availability of emerging compounds with mimicking or suppressor activity provides the opportunity for future therapeutic targeting of miRNAs. The present paper is focusing on miRNAs which, according to current knowledge, favorably impact on AML outcomes, being regarded as tumor suppressors, and reviews their role in macrophage polarization. We are focusing on miRNA expression in the setting of AML, but data on correlations between miRNA expression and macrophage polarization is mostly coming from studies involving normal tissue.

Identification of Early Recurrence Factors in Childhood and Adolescent B-Cell Acute Lymphoblastic Leukemia Based on Integrated Bioinformatics Analysis

Over the past 50 years, great progress has been made in the diagnosis and treatment of acute lymphoblastic leukemia (ALL), especially in pediatric patients. However, early recurrence is still an important threat to the survival of patients. In this study, we used integrated bioinformatics analysis to look for biomarkers of early recurrence of B-cell ALL (B-ALL) in childhood and adolescent patients. Firstly, we obtained gene expression profiles from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database and the Gene Expression Omnibus (GEO) database. Then, we identified differentially expressed genes (DEGs) based on whether the disease relapsed early. LASSO and Cox regression analysis were applied to identify a subset of four genes: HOXA7, S100A11, S100A10, and IFI44L. A genetic risk score model was constructed based on these four optimal prognostic genes. Time-dependent receiver operating characteristic (ROC) curves were used to evaluate the predictive value of this prognostic model (3-, 5-, and 10-year AUC values >0.7). The risk model was significantly associated with overall survival (OS) and event-free survival in B-ALL (all p < 0.0001). In addition, a high risk score was an independent poor prognostic risk factor for OS (p < 0.001; HR = 3.396; 95% CI: 2.387-4.832). Finally, the genetic risk model was successfully tested in B-ALL using an external validation set. The results suggested that this model could be a novel predictive tool for early recurrence and prognosis of B-ALL.

LINC00963 facilitates acute myeloid leukemia development by modulating miR-608/MMP-15

Despite continuous improvements of AML therapy, the prognosis of AML patients remains unsatisfactory. Recently, lncRNAs have been reported to participate in the development of AML. Our data demonstrated that MMP15 and LINC00963 were upregulated and miR-608 was decreased in AML cells (THP-1, HL-60, HEL and MOLM-13) compared to HS-5 cells. RT-qPCR results showed that LINC00963 levels were higher in the serum and bone marrow of AML cases than in controls. Moreover, overexpression of LINC00963 promoted AML cell growth and EMT progression in both THP-1 and HL-60 cells. Furthermore, miR-608 levels were downregulated in the serum and bone marrow of AML cases compared with controls, and Pearson's correlation analysis indicated that LINC00963 was negatively correlated with miR-608 in the serum and bone marrow of AML samples. In addition, we demonstrated that LINC00963 sponged miR-608 expression and that MMP-15 was a target of miR-608 in AML cells. Finally, rescue experiments indicated that ectopic expression of LINC00963 accelerated cell growth and EMT development by modulating MMP-15. These data demonstrated that LINC00963 acted as an oncogene and may be a potential target for AML treatment.

MicroRNA in leukemia: Tumor suppressors and oncogenes with prognostic potential

Leukemia is known as a progressive malignant disease, which destroys the blood-forming organs and results in adverse effects on the proliferation and development of leukocytes and their precursors in the blood and bone marrow. There are four main classes of leukemia including acute leukemia, chronic leukemia, myelogenous leukemia, and lymphocytic leukemia. Given that a variety of internal and external factors could be associated with the initiation and progression of different types of leukemia. One of the important factors is epigenetic regulators such as microRNAs (miRNAs) and long noncoding RNAs (ncRNA). MiRNAs are short ncRNAs which act as tumor suppressor (i.e., miR-15, miR-16, let-7, and miR-127) or oncogene (i.e., miR-155, miR-17-92, miR-21, miR-125b, miR-93, miR-143-p3, miR-196b, and miR-223) in leukemia. It has been shown that deregulation of these molecules are associated with the initiation and progression of leukemia. Hence, miRNAs could be used as potential therapeutic candidates in the treatment of patients with leukemia. Moreover, increasing evidence revealed that miRNAs could be used as diagnostic and prognostic biomarkers in monitoring patients in early stages of disease or after received chemotherapy regimen. It seems that identification and development of new miRNAs could pave to the way to the development new therapeutic platforms for patients with leukemia. Here, we summarized various miRNAs as tumor suppressor and oncogene which could be introduced as therapeutic targets in treatment of leukemia.

Abnormal microRNA expression in the course of hematological malignancies

Research on the carcinogenesis process is currently focused primarily on understanding its genetic basis and molecular abnormalities that may be predictive factors and therapeutic targets. It was clearly confirmed recently that microRNAs are involved in the mechanisms of leukocyte development, differentiation, and apoptosis, as well as in the pathogenesis of proliferative diseases of the hematopoietic system. Currently, research strategies allow determination of the deregulation of microRNA profiles in relation to other cytogenetic aberrations, as well as prognostic factors and primary end points. The problem of the possibility of their use as therapeutic targets is also increasingly discussed. In this article, we analyze literature data on abnormalities in microRNA expression in proliferative diseases of the hematopoietic system in the context of classic cytogenetic and molecular aberrations.

The interplay between critical transcription factors and microRNAs in the control of normal and malignant myelopoiesis

Myelopoiesis is a complex process driven by essential transcription factors, including C/EBPα, PU.1, RUNX1, KLF4 and IRF8. Together, these factors are critical for the control of myeloid progenitor cell expansion and lineage determination in the development of granulocytes and monocytes/macrophages. MicroRNAs (miRNAs) are expressed in a cell type and lineage specific manner. There is increasing evidence that miRNAs fine-tune the expression of hematopoietic lineage-specific transcription factors and drive the lineage decisions of hematopoietic progenitor cells. In this review, we discuss recently discovered self-activating and feed-back mechanisms in which transcription factors and miRNAs interact during myeloid cell development. Furthermore, we delineate how some of these mechanisms are affected in acute myeloid leukemia (AML) and how disrupted transcription factor-miRNA interplays contribute to leukemogenesis.

miRNAs in acute myeloid leukemia

MicroRNAs (miRNAs) are small, non-coding RNAs found throughout the eukaryotes that control the expression of a number of genes involved in commitment and differentiation of hematopoietic stem cells and tumorigenesis. Widespread dysregulation of miRNAs have been found in hematological malignancies, including human acute myeloid leukemia (AML). A comprehensive understanding of the role of miRNAs within the complex regulatory networks that are disrupted in malignant AML cells is a prerequisite for the development of therapeutic strategies employing miRNA modulators. Herein, we review the roles of emerging miRNAs and the miRNAs regulatory networks in AML pathogenesis, prognosis, and miRNA-directed therapies.

MicroRNAs as New Biomarkers for Diagnosis and Prognosis, and as Potential Therapeutic Targets in Acute Myeloid Leukemia

Acute myeloid leukemias (AML) are clonal disorders of hematopoietic progenitor cells which are characterized by relevant heterogeneity in terms of phenotypic, genotypic, and clinical features. Among the genetic aberrations that control disease development there are microRNAs (miRNAs). miRNAs are small non-coding RNAs that regulate, at post-transcriptional level, translation and stability of mRNAs. It is now established that deregulated miRNA expression is a prominent feature in AML. Functional studies have shown that miRNAs play an important role in AML pathogenesis and miRNA expression signatures are associated with chemotherapy response and clinical outcome. In this review we summarized miRNA signature in AML with different cytogenetic, molecular and clinical characteristics. Moreover, we reviewed the miRNA regulatory network in AML pathogenesis and we discussed the potential use of cellular and circulating miRNAs as biomarkers for diagnosis and prognosis and as therapeutic targets.

MiR-124 contributes to glucocorticoid resistance in acute lymphoblastic leukemia by promoting proliferation, inhibiting apoptosis and targeting the glucocorticoid receptor

Acute lymphoblastic leukemia (ALL) is characterized by the accumulation of abnormal lymphoblasts in the bone marrow and blood. Though great progress has been made for improvement in clinical treatment during the past decades, some children with ALL still relapsed. Glucocorticoid (GC) resistance is an important clinical problem for ALL treatment failure. Therefore, further understanding of the mechanism of GC resistance and exploring novel therapeutic strategies are crucial for improving treatment outcome. The reported involvement of microRNAs (miRNAs) in drug resistance implied that deregulated miRNA expression might contribute to GC treatment response of ALL. However, individual miRNAs and their functional mechanisms potentially involved in the GC response are still largely unknown. In the present study, we found that miR-124 was up-regulated in prednisone insensitive human ALL cell line and prednisone-poor response ALL patients. Furthermore, it was found that miR-124 might contribute to GC resistance by promoting proliferation and inhibiting apoptosis of ALL cells. Importantly, we validated that miR-124, targeted and decreased the expression of glucocorticoid receptor (NR3C1), prevented the inhibitory effect of GC in ALL. These findings strongly suggest that miR-124 is critical in poor GC response and may serve as a potential therapeutic target in ALL with poor GC resistance.

MicroRNA: an important regulator in acute myeloid leukemia

MicroRNAs (miRNAs) are a general class of endogenous non-coding RNAs with a length of 22 nucleotides, widely existing in diverse species and playing important roles in malignancies initiation and progression. MiRNAs are essential to many in vivo biological processes such as cell proliferation, apoptosis, immune response, and tumorigenesis. Significant progress till date has been made in understanding the roles of microRNAs in normal hematopoiesis and hematopoietic malignant diseases. In this review, we summarize the particular signatures of microRNAs in acute myeloid leukemia (AML) patients with specific karyotype and the clinical significance of microRNAs in early diagnosis and treatment. MicroRNAs hypermethylation was also proved to correlate with the pathogenesis of AML. However, the target genes and exact pathways of microRNAs participating in these processes are still unknown and more efforts need to be made in the near future.

MicroRNAs as prognostic biomarker and relapse indicator in leukemia

Despite significant progress in the treatment of different types of leukemia, relapse remains a challenging clinical problem that is observed in a number of patients who are often resistant to chemotherapy and exhibit multi-drug resistance. Identification of new functional biomarkers, including microRNAs, is essential to determine prognosis and relapse at the time of diagnosis. The aim of this study was to detect the specific microRNAs involved in predicting relapse or progression in acute and chronic leukemias, as well as their relationship with overall survival (OS) and relapse-free survival (RFS). The relevant literature was identified through a PubMed and Scholar search (2008-2016) of English-language papers using the terms Leukemia, microRNAs, survival and relapse. Different leukemia types and subtypes show specific microRNA expression profile and different changes, which can be useful in the differentiation between leukemias and evaluation of relapse at the time of diagnosis. Altered microRNA expression profiles can turn these molecules into oncogenes or tumor suppressors, which affect the expression of relapse-related genes. Therefore, monitoring of specific microRNA expression profiles from diagnosis and during follow-up of patients can contribute to the assessment of outcome and determination of relapse and prognosis of leukemic patients.

Cholinergic Machinery as Relevant Target in Acute Lymphoblastic T Leukemia

Various types of non-neuronal cells, including tumors, are able to produce acetylcholine (ACh), which acts as an autocrine/paracrine growth factor. T lymphocytes represent a key component of the non-neuronal cholinergic system. T cells-derived ACh is involved in a stimulation of their activation and proliferation, and acts as a regulator of immune response. The aim of the present work was to summarize the data about components of cholinergic machinery in T lymphocytes, with an emphasis on the comparison of healthy and leukemic T cells. Cell lines derived from acute lymphoblastic leukemias of T lineage (T-ALL) were found to produce a considerably higher amount of ACh than healthy T lymphocytes. Additionally, ACh produced by T-ALL is not efficiently hydrolyzed, because acetylcholinesterase (AChE) activity is drastically decreased in these cells. Up-regulation of muscarinic ACh receptors was also demonstrated at expression and functional level, whereas nicotinic ACh receptors seem to play a less important role and not form functional channels in cells derived from T-ALL. We hypothesized that ACh over-produced in T-ALL may act as an autocrine growth factor and play an important role in leukemic clonal expansion through shaping of intracellular Ca²⁺ signals. We suggest that cholinergic machinery may be attractive targets for new drugs against T-ALL. Specifically, testing of high affinity antagonists of muscarinic ACh receptors as well as antagomiRs, which interfere with miRNAs involved in the suppression of AChE expression, may be the first choice options.

Clinical significance of microRNAs in chronic and acute human leukemia

Small non-coding microRNAs (miRNAs) are epigenetic regulators that target specific cellular mRNA to modulate gene expression patterns and cellular signaling pathways. miRNAs are involved in a wide range of biological processes and are frequently deregulated in human cancers. Numerous miRNAs promote tumorigenesis and cancer progression by enhancing tumor growth, angiogenesis, invasion and immune evasion, while others have tumor suppressive effects (Hayes, et al., Trends Mol Med 20(8): 460-9, 2014; Stahlhut and Slack, Genome Med 5 (12): 111, 2013). The expression profile of cancer miRNAs can be used to predict patient prognosis and clinical response to treatment (Bouchie, Nat Biotechnol 31(7): 577, 2013). The majority of miRNAs are intracellular localized, however circulating miRNAs have been detected in various body fluids and represent new biomarkers of solid and hematologic cancers (Fabris and Calin, Mol Oncol 10(3):503-8, 2016; Allegra, et al., Int J Oncol 41(6): 1897-912, 2012). This review describes the clinical relevance of miRNAs, lncRNAs and snoRNAs in the diagnosis, prognosis and treatment response in patients with chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML) and acute adult T-cell leukemia (ATL).

The diagnosis, prognosis, and therapeutic application of MicroRNAs in haematological malignancies

OBJECTIVE

MicroRNAs (miRNAs) are small noncoding RNA molecules that participate in vital cell processes such as proliferation, apoptosis, and differentiation. In recent years, they have been proven to play vital roles in haematological malignancies. In this review we briefly introduce some basic knowledge of microRNAs and summarize their ectopic expression in haematological malignancies, especially in leukaemia. We will also discuss the potential of microRNAs in the diagnosis of leukaemia, in the determination of the clinical prognosis of diverse subtypes, and in targeted therapy.

DISCUSSION

Despite current adoption of novel biological agents combining traditional chemotherapy regimens, leukaemia remains to have undesirable clinical outcomes due to inaccurate diagnosis, invasiveness of the disease, and patients' intolerance to chemotherapy, thus brand new therapeutic directions are urgently needed. MiRNAs regulate gene expression by means of binding to the 3'-untranslated regions of corresponding mRNAs, leading to the degradation of targeted mRNA or the inhibition of translation. It has been confirmed that they can either function as tumour inhibitors, or may trigger tumourigenesis in certain situations, this specific dual characteristic undoubtedly attract scientists to explore their roles in haematological malignancies. It is of great necessity to summarize the roles of miRNAs in haematological malignancies diagnosis, prognosis evaluation, and clinical treatment.

CONCLUSIONS

Future studies may take full advantage of miRNAs detection in diagnosing, in choosing targeted biological therapy, and in avoiding predictable side effect, thus the overall survival rate and cure efficiency of leukaemia should improve.

Overexpression of miR-210 is Associated with Poor Prognosis of Acute Myeloid Leukemia

Background

MicroRNAs play important roles in regulation of the initiation and progression of AML. MiR-210 is closely related with cancer development; however, whether miR-210 expression level correlates with clinical correlation in AML is unknown. Thus, the aim of this study was to investigate the potential relationship between miR-210 expression and AML prognosis.

Material/Methods

Real-time quantitative PCR was carried out to examine the expression level of miR-210 in bone marrow and serum obtained from AML patients and healthy controls. Then the correlation between miR-210 expression and a variety of important clinical parameters (such as overall survival, relapse-free survival, and prognostic value) were further studied.

Results

The expression level of miR-210 was significantly higher in the bone marrow and serum of AML patients than that of healthy controls (p<0.001). Moreover, miR-210 expression was associated with various AML clinicopathological parameters, including FAB classification and cytogenetics. The serum miR-210 expression level was reduced significantly when the patients achieved complete remission (p=0.02). The high miR-210 expression group had both poorer relapse-free survival (p=0.015) and worse overall survival (p=0.008). In the multivariate analysis model, miR-210 was identified as an independent prognostic marker.

Conclusions

MiR-210 up-regulation was associated with poor prognosis in AML and it might be useful as a marker for predicting the clinical outcome of AML patients.

Low expression of circulating microRNA-328 is associated with poor prognosis in patients with acute myeloid leukemia

BACKGROUND

Dysregulation of circulating miR-328 has been identified in several tumors and is associated with prognosis of patients. However, the expression pattern of miR-328 and the impact on prognosis has not yet been studied in acute myeloid leukemia (AML). The purpose of this study is to investigate the expression status of miR-328 and its clinical significance in AML patients.

METHODS

RNA was extracted from plasma of 176 patients with newly diagnosed AML and 70 healthy volunteers. The miR-328 expression was examined by Realtime quantitative PCR. The association of circulating miR-328 expression with clinicopathological factors and prognosis of AML patients was statistically analyzed.

RESULTS

The expression of miR-328 was significantly downregulated in AML patients (median value 22.99, range: 3.63-242.0) compared with those of healthy controls (median value 89.17, range: 12.05-397.7; P < 0.001), and miR-328 expression was markedly increased in patients after treatment than before (23.40 ± 1.76 vs. 46.61 ± 3.83, P < 0.001). Moreover, low levels of miR-328 were associated with a higher white blood cell count and BM blast count (P = 0.026 and P = 0.003, respectively), and lower hemoglobin and platelet count (P = 0.004 and P = 0.022, respectively). Patients with low miR-328 expression had a relatively poor overall survival (P = 0.022) and shorter relapse-free survival (P = 0.008) than those with high miR-328 expression. In addition, low miR-328 expression was an independent prognostic factors for both OS (P = 0.017) and RFS (P = 0.023).

CONCLUSIONS

Circulating miR-328 downregulation is a common event and is associated with poor clinical outcome in AML patients.

STAT3 is involved in miR-124-mediated suppressive effects on esophageal cancer cells

Background

Esophageal cancer (EC) is one of the most common cancers worldwide. The cancer-related inflammation pathway- signal transducer and activator of transition 3 (STAT3) signaling pathway has been reported to play critical role in its initiation and progression, while the way mediated its hyperactivation remains elusive so far. Accumulating studies reported the important role of microRNAs (miRNAs) in the regulation of gene expression, among of which, the miR-124/STAT3 interaction has been widely reported in various cancers, while its role in EC has not been investigated yet.

Methods

Firstly, we identified the target role of STAT3 in esophageal cancers using Dual-luciferase reporter assays. Next, we explored the expression of miR-124 in EC tissues. To further investigate its effects on the malignant phenotype of EC cells, we completed a series of experiments. Through transfection with miR-124 mimic, the expression of miR-124 in esophageal cancer cell lines, Eca109 and TE-1, were restored. Next, we detected the effects of ectopic miR-124 expression on the proliferation, cell cycle distribution, apoptosis, migration and invasion of EC cells in vitro, and the tumor growth in vivo.

Results

Dual-luciferase assays identified that STAT3 is a target gene of miR-124 in esophageal cancer cells. Over-expression of miR-124 significantly down-regulated the mRNA and protein levels of STAT3. Moreover, we found that the expression of miR-124 was consistently suppressed in esophageal cancer tissues and cell lines. Next, functional experiments showed that ectopic expression of miR-124 in EC cells induced a complex phenotype, namely an inhibition of cell proliferation, block of G1/S phase transition, induction of cell apoptosis, and suppression of cell invasion in vitro, as well as inhibition of tumor growth in vivo. Moreover, restored the expression of STAT3 in esophageal cancer cells transfected with miR-124 before, could partially abolished the suppressive effects of miR-124 on the proliferation and invasion of Eca109 cells.

Conclusion

Collectively, these data suggest that miR-124 functions as a tumor suppressor in esophageal cancer through, at least partially, targeting STAT3 signaling pathway.