MiR-15b regulates cell differentiation and survival by targeting CCNE1 in APL cell lines

Role of MicroRNAs in Acute Myeloid Leukemia

MicroRNA (miRNA), a significant class of regulatory non-coding RNA (ncRNA), can regulate the expression of numerous protein-coding messenger RNAs (mRNAs). miRNA plays an important part in shaping the human transcriptome. So far, in the human genome, about 2500 miRNAs have been found. Acute myeloid leukemia (AML) belongs to a malignant clonal disorder of hematopoietic stem cells and is characterized by the uncontrolled clonal proliferation of abnormal progenitor cells in the bone marrow and blood. For the past several years, significant scientific attention has been attracted to the role of miRNAs in AML, since alterations in the expression levels of miRNAs may contribute to AML development. This review describes the main functions of non-coding RNA classes and presents miRNA biogenesis. This study aims to review recent reports about altered microRNA expression and their influence on AML cell survival, cell cycle, and apoptotic potential. Additionally, it summarizes the correlations between miRNAs and their target mRNAs in AML and outlines the role of particular miRNAs in AML subtypes according to ELN recommendations.

Clinical Value of Serum miRNA in Patients with Acute Promyelocytic Leukemia

Objective

To explore the clinical value of specific miRNA in patients with acute promyelocytic leukemia.

Methods

129 patients with acute promyelocytic leukemia diagnosed in our hospital from January 2015 to January 2020 were selected as the observation group. At the same time, 74 patients with nonacute promyelocytic leukemia who underwent bone marrow aspiration were included as the control group. The expression levels of miR-126-5p and miR-13, different characteristic parameters, and prognosis were compared between the two groups, and the clinical significance of miR-126-5p and miR-13 in acute promyelocytic leukemia was analyzed.

Results

The expression of miR-126-5p (12.31 ± 2.25 versus 17.30 ± 3.28) and miR-13 (16.05 ± 3.47 versus 21.66 ± 2.18) in the observation group was significantly lower than that in the control group (P < 0.05). The expression level of miR-126-5p was significantly correlated with lactate dehydrogenase level, HGB level, NPM1 mutant type, and complete remission (P < 0.05). The expression level of miR-13 was significantly correlated with HGB level, NPM1 mutant type, and complete remission (P < 0.05). Both expression levels of miR-126-5p and miR-13 were not correlated with sex, age, WBC, PLT, proportion of bone marrow primordial cells, hepatomegaly, splenomegaly, lymph node enlargement, and FLT3-ITD (P > 0.05). Cox multivariate regression analysis showed that peripheral blood WBC, bone marrow blast cell count, and miR-126-5p and miR-13 were prognostic factors in patients with acute promyelocytic leukemia (P < 0.05). The sensitivity, specificity, accuracy, and AUC of serum miR-126-5p prediction were 75.83%, 84.56%, 82.17%, and 0.729, respectively. The sensitivity, specificity, accuracy, and AUC of serum miR-13 prediction were 78.64%, 88.49%, 86.20% and 0.882, respectively.

Conclusion

Serum miR-126-5p and miR-13 are closely related to the prognosis of patients with acute promyelocytic leukemia. Serum miR-126-5p and miR-13 can be used as reliable indexes to predict the prognosis of patients.

LncRNA MAGI2-As3 Suppresses the Proliferation and Invasion of Cervical Cancer by Sponging MiR-15b

BACKGROUND

Cervical cancer is the leading cause of cancer deaths among women, and more than 85% of cervical cancer deaths occur in low and middle-income countries. The purpose of this study is to investigate the functions of MAGI2-AS3 and miR-15b in cervical cancer.

MATERIALS AND METHODS

The mRNA levels of MAGI2-AS3, miR-15b, and CCNE1 were evaluated using RT-qPCR assay. Dual-luciferase reporter gene assay was used to confirm whether miR-15b binds to CCNE1.

RESULTS

LncRNA MAGI2-AS3 was downregulated, while miR-15b was upregulated in cervical cancer. Cervical cancer patients with low expression of MAGI2-AS3 have a poor prognosis. Upregulation of MAGI2-AS3 inhibited proliferative and invasive abilities of HeLa cells via regulating the expression of miRNA-15b. MiR-15b inhibitor suppressed cell proliferation and invasion. CCNE1 was a direct target gene of miR-15b, which binds to the 3'-UTR of its mRNA. MiR-15b partially reversed the inhibitory effect of overexpression of MAGI2-AS3 on the proliferation and invasion of HeLa cells. MAGI2-AS3 mediated the expression of CCNE1 in HeLa cells.

CONCLUSION

LncRNA MAGI2-AS3 inhibits the proliferation and invasion of cervical cancer cells via the miRNA-15/CCNE1 axis. Our results illustrates that MAGI2-AS3 can be used as a useful clinical predictor for early diagnosis and prognosis assessment of cervical cancer.

MicroRNA-218 aggravates H2O2-induced damage in PC12 cells via spred2-mediated autophagy

The current study aimed to investigate the effects and underlying mechanism of miR-218 in H₂O₂-induced neuronal injury. The impacts of miR-218 knockdown on cell viability, apoptosis and autophagy-associated proteins were detected by Cell Counting Kit-8 assay, flow cytometry and western blotting in H₂O₂-injured PC12 cells, respectively. Reverse transcription-quantitative PCR (RT-qPCR) and western blotting was executed to explore the expression level of miR-218 and sprouty-related EVH1 domainprotein2 (spred2) in H₂O₂-stimulated cells. Besides, the regulatory association between miR-218 and spred2 was explored through bioinformatics and luciferase reporter assay. Following knockdown of miR-218 and spred2, the functions of miR-218 and spred2 in H₂O₂-injured cells were further studied. High expression level of miR-218 was observed in H₂O₂-disposed PC12 cells, while spred2 expression level was downregulated. Knockdown of miR-218 expression alleviated H₂O₂-induced PC12 cell injury by increasing cell proliferation, and decreasing apoptosis and autophagy. Furthermore, spred2 was identified as a direct target of miR-218 and was negatively regulated by miR-218. Moreover, suppression of spred2 abrogated the protective effects of miR-218 inhibition on H₂O₂-injured PC12 cells. Depletion of miR-218 protected PC12 cells against H₂O₂-induced cell injury via the upregulation of spred2, which provided a promising therapeutic strategy for spinal cord injury.

CircDENND2A Promotes Non-small Cell Lung Cancer Progression via Regulating MiR-34a/CCNE1 Signaling

The mechanism regulating non-small cell lung cancers (NSCLCs) is unclear. In this study, we aimed to determine the roles of DENN domain containing 2A (circDENND2A) in the progression of NSCLC. Circular RNAs (circRNAs) are composited by “head to tail” splicing of coding or non-coding RNAs (ncRNAs), whose crucial roles in human cancers had been revealed. CircDENND2A, a new circRNA, was revealed to induce cell proliferation and migration. Our data indicated that circDENND2A was a probable oncogene in human cancers. However, the roles of circDENND2A in NSCLC remained unknown. Here, we demonstrated that circDENND2A was down-regulated in NSCLC samples. Loss-of-function assays showed circDENND2A knockdown suppressed cell growth via inducing cell cycle arrest and apoptosis and inhibited cell migration and invasion. Bioinformatics analysis and competing endogenous RNA (ceRNA) network analysis revealed that circDENND2A was involved in regulating cell cycle and tumor protein p53 (TP53) signaling via miR-34a/CCNE1 (cyclin E1). Further validation showed that circDENND2A could directly bind to miR-34a, promoting CCNE1 expression in NSCLC. In addition, rescue assays demonstrated that restoration of CCNE1 significantly impaired the suppressive effects of circDENND2A silencing in terms of NSCLC growth, migration, and invasion. We thought this study indicated that circDENND2A/miR-34a/CCNE1 may be a potential therapeutic target for NSCLC.

Long Noncoding RNA RAET1K Enhances CCNE1 Expression and Cell Cycle Arrest of Lung Adenocarcinoma Cell by Sponging miRNA-135a-5p

Molecular dysregulation is believed to participate in the onset and progression of lung adenocarcinoma (LUAD). This study aimed to identify and evaluate the potential key long noncoding RNAs (lncRNAs) involved in the significant dysfunctional process of LUAD. We found that lncRNA retinoic acid early transcript 1K (RAET1K) was upregulated in tumor tissues and were correlated with a poor prognosis of patients with LUAD; further, for the first time, we detected the biological roles of RAET1K. Weighted gene correlation network and gene set enrichment analysis revealed that high RAET1K expression is related to cell cycle dysfunction through upregulated cyclin E1 (CCNE1) by targeting miR-135. The dual-luciferase reporter gene assay was performed to clarify the binding relationship between RAET1K and miR-135a-5p in transgenic A549 and H1299 cells. Real-time PCR and Western blot analyses showed that RAET1K overexpression and miR-135a-5p inhibition exerted a strong synergistic effect on CCNE1 expression, and cell cycle flow cytometry analysis was used to confirm the arrest of A549 and H1299 cells at the G1/S phase. The lncRNA RAET1K/miR-135a-5p axis might participate in the regulation of LUAD progression by influencing CCNE1 expression and the accumulation of cells arrested at the G1/S phase boundary.