Evaluation of the expression level of microRNA-21, microRNA-15a, microRNA-372 in human follicular fluid stem cells-derived oocyte-like cells (OLCs).

OBJECTIVE: Today, researchers have succeeded in achieving oocyte-like cells through the in vitro differentiation of stem cells. MicroRNAs are key regulators of oocyte development. In this study we decided to evaluate the expression pattern of microRNA-21, microRNA-15a, and microRNA-372 in oocyte-like cells, to determine the maturation stage of oocyte-like cells. METHODS: Human follicular fluid samples were collected and centrifuged, and their cells were divided into 3 groups; day 7 as control group, days 14 and 21. During this period, the cells were evaluated for their morphological appearance and viability by inverted microscopy. RNA isolation was performed and cDNA was reversely transcribed by specific stem-loop RT primers. Real-time RT-PCR was used to detect microRNA expression. RESULTS: The relative expression of microRNA-21 and microRNA-15a on day 21 was significantly down-regulated compared to the control group (day 7), but microRNA-372 did not show a significant difference. Also, on day 14 compared to the control group (day 7), microRNA-21 did not show a significant difference; but microRNA-15a and microRNA-372 were significantly down-regulated. MicroRNA-21 and microRNA-15a on day 21 compared to day 14 revealed down-regulated levels, but microRNA-372 revealed up-regulated levels. CONCLUSIONS: Our results showed significant decreases in the expression of microRNA-21 and microRNA-15a in oocyte-like cells, as well as in oocytes, which may lead to cytoplasmic maturation, germinal vesicle break down and the completion of meiosis І. In addition, down-regulation expression of microRNA-372 maybe a confirmation that mesenchymal stem cells have differentiated into germ cells, and these cells were differentiated into oocyte-like cells.

[Retracted] MicroRNA­15a­5p­targeting oncogene YAP1 inhibits cell viability and induces cell apoptosis in cervical cancer cells.

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that certain of the Transwell invasion assay data shown in Fig. 3A and B on p. 1306 were strikingly similar to data appearing in different form in a paper by different authors at a different research institute that had already been submitted for publication. Owing to the fact that the contentious data in the above article had already been submitted for publication prior to its submission to International Journal of Molecular Medicine, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they accepted the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [International Journal of Molecular Medicine 46: 1301­1310, 2020; DOI: 10.3892/ijmm.2020.4704].

Research progress in effects of microRNA-15a and microRNA-16 on fibrotic diseases. / å¾®RNA-15a和微RNA-16åœ¨çº¤ç»´åŒ–ç–¾ç— ä¸­ä½œç”¨çš„ç ”ç©¶è¿›å±•.

MicroRNA (miR) is a class of highly conserved non-coding single-stranded RNA widely existing in mammals, which can negatively regulate the expression of targeting genes after transcription. As a key regulator, miR negatively regulates the expression of the targeting genes and disrupts important molecular signaling pathways, leading to the imbalance of multiple pathways such as tissue repair and inflammation involved in the fibrotic process. Among them, miR-15a/16 can participate in regulating and controlling the fibrotic process of various organs, including liver, lung, heart, kidney and other fibrotic diseases by acting on cell proliferation and transformation, extracellular matrix proteins production and degradation, inflammation and other important cell functions. It has potential diagnostic and therapeutic value. Clarifying the biological function of miR-15a/16 and its mechanism for action and therapeutic application prospects in various fibrotic lesions are of great significance for the molecular targeted treatment of fibrotic diseases.

MicroRNA-15a/ß1,4-GalT-I axis contributes to cartilage degeneration via NF-κB signaling in osteoarthritis.

OBJECTIVE: Osteoarthritis is a condition characterized by articular cartilage degradation. The increased expression of ß1,4-Galactosyltransferase-I (ß1,4-GalT-I) in the articular cartilage of osteoarthritis patients was related to an inflammatory response. The aim of this study was to elucidate the role of ß1,4-GalT-I in osteoarthritis. This study aimed to determine the function of 1,4-GalT-I in osteoarthritis. METHODS: The osteoarthritis mouse model with the destabilization of the medial meniscus was established by microsurgical technique. Pathological changes in articular cartilage were observed by hematoxylin and eosin staining and safranin O-fast green staining. Quantitative real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assays were used to observe mRNA and protein expression, respectively. RNA interactions were verified by a luciferase reporter assay. SA-ß-Gal staining was used to assess chondrocyte senescence. Immunofluorescence staining was conducted to observe the localization of Nuclear Factor-kappaB (NF-κB). RESULTS: ß1,4-GalT-I and microRNA-15a (miR-15a) show high and low expression in the articular cartilage of osteoarthritis, respectively. MiR-15a inhibits the mRNA translation of ß1,4-GalT-I. ß1,4-GalT-I promotes extracellular matrix degradation, senescence, and NF-κB activation in IL-1ß-stimulated chondrocytes, which can be reversed by overexpression of miR-15a. Intra-articular injection of microRNA-15a ameliorates cartilage degeneration by inhibiting ß1,4-GalT-I and phosphorylation of NF-κB in vivo. CONCLUSION: The authors clarified that the miR-15a/ß1,4-GalT-I axis inhibits the phosphorylation of NF-κB thereby inhibiting extracellular matrix degradation and senescence in chondrocytes to alleviate cartilage degeneration in osteoarthritis. MiR-15a and ß1,4-GalT-I may serve as potentially effective targets for the future treatment of osteoarthritis.

Scutellarin inhibits glioma cell proliferation by up-regulating miR-15a expression.

OBJECTIVE: To investigate the effect of scutellarin on the proliferation of glioma cells through microRNA (miR)-15a. METHODS: Human glioma cell line T98G was cultured in vitro and divided into control group (without treatment), scutellarin group (with 10, 20, 40, 80, 160 µg/mL scutellarin, respectively), miR-15a negative control group (transfected with negative control-miR-15a + 80 µg/mL scutellarin) and miR-15a inhibitor group (transfected with miR-15a siRNA + 80 µg/mL scutellarin). The proliferation of T98G cells was detected by cell counting kit-8 (CCK-8), and the expression of miR-15a in T98G cells was detected by real-time fluorescence quantitative PCR (qRT-PCR). The apoptosis of T98G cells was assessed by flow cytometry, and the invasion of T98G cells was compared by Transwell method. The levels of proliferating cell nuclear antigen (PCNA), Bcl-2 related X protein (Bax) and matrix metalloproteinase 9 (MMP-9) in T98G cells were detected by Western blot (WB). RESULTS: Compared with that in the control group, the OD value of T98G cells in scutellarin group was significantly lower (P<0.05), with the increase of scutellarin concentration, the OD value of T98G cells decreased in turn, and 80 µg/mL was used as the optimal concentration of scutellarin to treat T98G cells for subsequent experiments. Compared with those in the control group, the miR-15a expression, apoptosis rate and Bax protein expression in T98G cells of scutellarin group were higher (P<0.05), and the OD value, number of invasive cells, PCNA and MMP-9 protein levels were lower (P<0.05). Compared with scutellarin group and miR-15a negative control group, the miR-15a expression, apoptosis rate and Bax protein expression in T98G cells of miR-15a inhibitor group were lower (P<0.05), and the OD value, number of invasive cells, PCNA and MMP-9 protein levels were higher (P<0.05). CONCLUSIONS: Scutellarin can inhibit the proliferation, invasion and induce the apoptosis of glioma cells, which may be mediated by up-regulating the expression of miR-15a.

Generation of miR-15a/16-1 cluster-deficient human induced pluripotent stem cell line (DMBi001-A-2) using CRISPR/Cas9 gene editing.

miR-15a/16-1 cluster, composed of MIR15A and MIR16-1 genes located in close proximity on chromosome 13 was described to regulate post-natal cell cycle withdrawal of cardiomyocytes in mice. In humans, on the other hand, the level of miR-15a-5p and miR-16-p was negatively associated with the severity of cardiac hypertrophy. Therefore, to better understand the role of these microRNAs in human cardiomyocytes in regard to their proliferative potential and hypertrophic growth, we generated hiPSC line with complete deletion of miR-15a/16-1 cluster using CRISPR/Cas9 gene editing. Obtained cells demonstrate expression of pluripotency markers, differentiation capacity into all three germ layers and normal karyotype.

MicroRNA-15a/β1,4-GalT-I axis contributes to cartilage degeneration via NF-κB signaling in osteoarthritis

Abstract Objective Osteoarthritis is a condition characterized by articular cartilage degradation. The increased expression of β1,4-Galactosyltransferase-I (β1,4-GalT-I) in the articular cartilage of osteoarthritis patients was related to an inflammatory response. The aim of this study was to elucidate the role of β1,4-GalT-I in osteoarthritis. This study aimed to determine the function of 1,4-GalT-I in osteoarthritis. Methods The osteoarthritis mouse model with the destabilization of the medial meniscus was established by microsurgical technique. Pathological changes in articular cartilage were observed by hematoxylin and eosin staining and safranin O-fast green staining. Quantitative real-time polymerase chain reaction, western blot, and enzyme-linked immunosorbent assays were used to observe mRNA and protein expression, respectively. RNA interactions were verified by a luciferase reporter assay. SA-β-Gal staining was used to assess chondrocyte senescence. Immunofluorescence staining was conducted to observe the localization of Nuclear Factor-kappaB (NF-κB). Results β1,4-GalT-I and microRNA-15a (miR-15a) show high and low expression in the articular cartilage of osteoarthritis, respectively. MiR-15a inhibits the mRNA translation of β1,4-GalT-I. β1,4-GalT-I promotes extracellular matrix degradation, senescence, and NF-κB activation in IL-1β-stimulated chondrocytes, which can be reversed by overexpression of miR-15a. Intra-articular injection of microRNA-15a ameliorates cartilage degeneration by inhibiting β1,4-GalT-I and phosphorylation of NF-κB in vivo. Conclusion The authors clarified that the miR-15a/β1,4-GalT-I axis inhibits the phosphorylation of NF-κB thereby inhibiting extracellular matrix degradation and senescence in chondrocytes to alleviate cartilage degeneration in osteoarthritis. MiR-15a and β1,4-GalT-I may serve as potentially effective targets for the future treatment of osteoarthritis.

Research progress in effects of microRNA -15a and microRNA -16 on fibrotic diseases / 中南大学学报(医学版)

MicroRNA (miR) is a class of highly conserved non-coding single-stranded RNA widely existing in mammals, which can negatively regulate the expression of targeting genes after transcription. As a key regulator, miR negatively regulates the expression of the targeting genes and disrupts important molecular signaling pathways, leading to the imbalance of multiple pathways such as tissue repair and inflammation involved in the fibrotic process. Among them, miR-15a/16 can participate in regulating and controlling the fibrotic process of various organs, including liver, lung, heart, kidney and other fibrotic diseases by acting on cell proliferation and transformation, extracellular matrix proteins production and degradation, inflammation and other important cell functions. It has potential diagnostic and therapeutic value. Clarifying the biological function of miR-15a/16 and its mechanism for action and therapeutic application prospects in various fibrotic lesions are of great significance for the molecular targeted treatment of fibrotic diseases.

Bone marrow mesenchymal stem cell-derived exosomes carrying long noncoding RNA ZFAS1 alleviate oxidative stress and inflammation in ischemic stroke by inhibiting microRNA-15a-5p.

BACKGROUND/AIM: Bone marrow mesenchymal stem cell (BMSC)-derived exosomes can prevent oxidative stress and inflammation in cerebral ischemia-reperfusion injury. This study intended to assess influences of BMSC-released exosomes on oxidative stress and inflammation following ischemic stroke. METHODS: In vitro and in vivo models were developed using oxygen-glucose deprivation/reperfusion (OGD/R) and middle cerebral artery occlusion (MCAO), respectively. After exosome isolation, co-culture experiments of BMSCs or BMSC-derived exosomes and OGD/R-treated BV-2 cells were implemented to evaluate the impacts of BMSCs or BMSC-secreted exosomes on proliferation, inflammation, oxidative stress, and apoptosis. The gain-of-function experiments of ZFAS1 or microRNA (miR)-15a-5p were conducted to investigate the associated mechanisms. Besides, MCAO mice were injected with exosomes from BMSCs overexpressing ZFAS1 for in vivo verification. The binding of ZFAS1 to miR-15a-5p was assessed through dual-luciferase reporter gene assay. RESULTS: Co-culture with BMSCs accelerated proliferation and downregulated IL-1ß, IL-6, and TNF-α in OGD/R-exposed BV-2 cells, accompanied by increased SOD level and decreased MDA level and apoptosis, all of which were nullified by inhibiting exosome secretion. Mechanistically, ZFAS1 bound to miR-15a-5p to negatively orchestrate its expression. In addition, BMSC-released exosomes or BMSC-secreted exosomal ZFAS1 augmented proliferation but reduced oxidative stress, apoptosis, and inflammation in OGD/R-exposed BV-2 cells, whereas these impacts of BMSC-released exosomal ZFAS1 were nullified by overexpressing miR-15a-5p. Moreover, BMSC-derived exosomal ZFAS1 diminished MCAO-induced oxidative stress, cerebral infarction, and inflammation in mice. CONCLUSIONS: Conclusively, BMSC-released exosomes might carry long noncoding RNA ZFAS1 to curb oxidative stress and inflammation related to ischemic stroke, which was possibly realized through miR-15a-5p inhibition.

Exosomal AFAP1-AS1 binds to microRNA-15a-5p to promote the proliferation, migration, and invasion of ectopic endometrial stromal cells in endometriosis.

BACKGROUND: Endometriosis (EMS) remains a major challenge to reproductive health due to multifactorial etiology, disease heterogeneity, and the lack of appropriate diagnostic markers and treatment. Eexosome (Exo) has become a major factor in progression of a variety of diseases. However, the mechanisms directing their role in the pathophysiology of EMS are ill-defined. Here, we aimed to investigate the clinical implications of actin filament associated protein 1-Antisense RNA 1 (AFAP1-AS1) in EMS. METHODS: Bioinformatics analysis was used to predict the expression and interaction of AFAP1-AS1, miR-15a-5p and BCL9 in EMS, and dual luciferase reporter assay was used to verify the targeted relationship of AFAP1-AS1, miR-15a-5p, and BCL9. The Exo from endometrial stromal cells (ESCs) was isolated and characterized by transmission electron microscopy (TEM) and Nanoparticle tracking analysis (NTA). Exosome uptake studies were performed. For in vitro assay, ectopic ESCs (EcESCs) proliferation, migration, and invasion were assessed by CCK-8 and Transwell assays. In vivo assay was performed by establishment of EMS mice to validate the result derived from in vitro assay. RESULTS: The Exo was successfully isolated from ESCs and we observed high expression of AFAP1-AS1 and BCL9 but low expression of miR-15a-5p in EMS. Moreover, Exo derived from EcESCs could deliver AFAP1-AS1 to EcESCs and thus promoting proliferation, migration, and invasion of ESCs. AFAP1-AS1 bound to BCL9, which was targeted by miR-15a-5p in EMS. In vivo experiments in nude mice revealed that inhibition of Exosomal AFAP1-AS1 suppressed migration and invasion of EcESCs through miR-15a-5p/BCL9. CONCLUSIONS: Collectively, these findings suggested that ESCs-derived Exo carrying AFAP1-AS1 contributed to EMS pathogenesis. This study might help us realize the etiology of EMS and improve the treatment of the related complications.

Human umbilical cord-mesenchymal stem cells-derived exosomes carrying microRNA-15a-5p possess therapeutic effects on Wilms tumor via regulating septin 2.

The exact mechanism of miR-15a-5p shuttled by human umbilical cord-mesenchymal stem cell-derived exosomes (hUC-MSCs-Exo) in Wilms tumor (WT) was estimated. WT tissues were collected clinically. miR-15a-5p and septin 2 (SEPT2) expression levels were examined in tissues . hUC-MSCs-Exo were transfected with miR-15a-5p-related oligonucleotides and co-cultured with WT cells (G-401). In addition, SEPT2 loss-of-function was performed in G-401 cells. The biological functions of G-401 cells after treatments were evaluated. Moreover, tumor formation tests further assessed the role of exosomal miR-15a-5p in WT. The miR-15a-5p level was lower and the SEPT2 level was higher in WT. hUC-MSCs-Exo impaired the biological functions of G-401 cells. hUC-MSCs-Exo carried upregulated miR-15a-5p into G-401 cells, thereby lessening the tumorigenic properties of G-401 cells. Inhibition of SEPT2 suppressed the biological function of WT cells and upregulated SEPT2 reversed hUC-MSCs-Exo-mediated inhibition of G-401 cell growth. The tumorigenicity of G-401 cells in mice was impaired by hUC-MSCs-Exo overexpressing miR-15a-5p. The data prove that miR-15a-5p shuttled by hUC-MSCs-Exo negatively regulates SEPT2 expression, and disrupts WT cell growth in vivo and in vitro.

Promoting effect of miR-15a on high glucose-induced oxidative stress in human lens epithelial cells and its mechanism / 中华实验眼科杂志

Objective:To investigate the effect of microRNA-15a (miR-15a) on the anti-oxidative stress ability of human lens epithelial cells (LECs) induced by high glucose and its possible mechanism.Methods:The anterior lens capsule specimens from patients with diabetic cataract (DC) and healthy donors were collected.The expressions of miR-15a and silent information regulator 1 (SIRT1) in the specimens were detected by real-time quantitative PCR (RT-qPCR) and Western blot, respectively.The human lens epithelial cell line HLEB-3 cells were cultured with 0, 10, 20, or 50 mmol/L glucose for 24 hours.The expression of miR-15a in the cells was detected by RT-qPCR.The expressions of SIRT1, forkhead transcription factor 3a (FOXO3a), and p53 proteins in the cells were determined by Western blot.The cell apoptosis was assayed by flow cytometry.The endogenous reactive oxygen species (ROS) content in the cells was measured by 2, 7-dichlorodihydrofluorescein diacetate (DCFH-DA). The total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, and malondialdehyde (MDA) activities in the cells were identified.HLEB-3 cells were transfected with miR-15a control or miR-15a inhibitor, then incubated with 50 mmol/L glucose for 24 hours.Cell apoptosis of the transfected cells was detected by flow cytometry.The endogenous ROS expression in the transfected cells was determined by DCFH-DA.The T-AOC, SOD, and GSH-Px activities as well as MDA concentration were measured.The relationship between miR-15a and SIRT1 was verified by dual-luciferase reporter assay.The SIRT1, FOXO3a, and p53 protein expressions in the transfected cells were detected by Western blot.This study was approved by an Ethics Committee of the Second Affiliated Hospital of Zhengzhou University (No.ZDEFY201803160023). Written informed consent was obtained from each subject.Results:The relative expression of miR-15a in normal lens anterior capsule tissue was 0.21±0.02, which was lower than 0.96±0.10 in lens anterior capsule tissue of DC patients, and the difference was statistically significant ( t=12.231, P<0.001). The relative expression of SIRT1 in the anterior lens capsule tissue was 0.89±0.09, which was higher than 0.31±0.05 in the anterior lens capsule tissue of DC patients, showing a statistically significant difference ( t=8.964, P<0.001). With the increase of glucose concentration, the relative expression of miR-15a, FOXO3a, and p53 in cells increased, and the relative expression of SIRT1 decreased; the apoptosis rate of cells increased; the ROS content and MDA concentration increased; the activities of T-AOC, SOD and GSH-Px decreased, and the differences were statistically significant (all at P<0.05). The apoptosis rate, ROS content, and MDA concentrations were higher in miR-15a control group than miR-15a inhibitor group, and the activities of T-AOC, SOD, and GSH-Px were lower in miR-15a control group than miR-15a inhibitor group, with statistically significant differences (all at P<0.05). The luciferase activity of the SIRT1-3'-untranslated region (UTR)-wild type (WT) reporter gene in miR-15a control group was significantly lower than that in miR-15a inhibitor group, and the difference was statistically significant ( t=5.978, P=0.004). No significant difference was found in the luciferase activity of the SIRT1-3'-UTR-mutant type (MUT) reporter gene ( t=0.432, P=0.688). The relative expressions of FOXO3a and p53 proteins were significantly higher in miR-15a control group than miR-15a inhibitor group, and the relative expression of SIRT1 protein was significantly lower in miR-15a control group than miR-15a inhibitor group, showing statistically significant differences (all at P<0.05). Conclusions:miR-15a can inhibit the anti-oxidative stress damage ability of LECs induced by high glucose, which may be achieved by inhibiting the expression of SIRT1 to up-regulate the activities of FOXO3a and p53, and aggravating apoptosis.

Correlation of serum microRNA-15a-5p level with prognosis and neoadjuvant chemotherapy response in patients with locally advanced gastric cancer / 中国医师进修杂志

Objective:To investigate the correlation between serum microRNA (miR)-15a-5p and prognosis, neoadjuvant chemotherapy (NAC) response in patients with locally advanced gastric cancer (LAGC).Methods:The clinical data of 122 patients with LAGC who underwent surgery after NAC in Eastern Theater Air Force Hospital of the Chinese People′s Liberation Army from May 2016 to April 2020 were analyzed retrospectively. The general clinical data and laboratory examination results of the patients were recorded. The expression level of serum miR-15a-5p was detected by real-time fluorescence quantitative polymerase chain reaction, and the relationship between the expression of miR-15a-5p and different clinical characteristics in patients with LAGC was analyzed. The pathological response was evaluated by Becker tumor regression grading, in which patients with grade 1a, 1b and 2 were sensitive group and patients with grade 3 were resistant group.Results:The patients with LAGC were divided into high expression (>1.038) and low expression (≤1.038) according to the median miR-15a-5p of 1.038 with 61 cases each. The expression level of serum miR-15a-5p was related to the preference for spicy food, endoscopic ultrasonography (EUS)-T stage and EUS-N stage ( P<0.01 or <0.05). According to the evaluation result of pathological reaction, there were 47 cases in resistance group and 74 cases in sensitive group. The serum miR-15a-5p in resistance group was significantly higher than that in sensitive group: 1.69 (1.39, 1.97) vs. 0.99 (0.96, 1.02), and there was statistical difference ( Z =-8.55, P<0.01). The receiver operating characteristic curve analysis result showed that the area under the curve of serum miR-15a-5p predicting NAC response was 0.959 (95% CI 0.929 to 0.990), the optimal cut-off value was 1.049, the sensitivity was 100.0%, and the specificity was 85.1%. Multivariate Logistic regression analysis result showed that miR-15a-5p was an independent risk factor for NAC response in patients with LAGC ( HR = 1 880.840, 95% CI 123.510 to 28 641.846, P<0.01). Kaplan-Meier survival curve analysis result showed that the median overall survival time and median progression free survival time in patients with high expression of miR-15a-5p were significantly shorter than those in patients with low expression of miR-15a-5p (19 months vs. 62 months and 12 months vs. 51 months), and there were statistical differences (log-rank χ2 = 41.99 and 61.97, P<0.01); the 10-year overall survival rate and 10-year progression free survival rate in patients with high expression of miR-15a-5p were significantly lower than those in patients with low expression of miR-15a-5p (4.9% vs. 52.5% and 24.6% vs. 85.2%), and there were statistical differences (log-rank χ2 = 33.70 and 45.32, P<0.01). Multivariate Cox regression analysis result showed that R 0 resection and miR-15a-5p were the independent risk factors affecting the overall survival time and progression free survival time in patients with LAGC (overall survival time: HR = 1.945 and 3.487, 95% CI 1.033 to 3.660 and 2.112 to 5.759, P<0.05 or <0.01; progression free survival time: HR = 2.427 and 6.335, 95% CI 1.069 to 5.510 and 3.341 to 12.013, P<0.05 or <0.01). Conclusions:The increase of serum miR-15a-5p level is related to NAC response and poor prognosis in patients with LAGC. It can be used as a reliable biomarker to predict the prognosis and NAC response of LAGC.

Exosomal microRNA-15a from ACHN cells aggravates clear cell renal cell carcinoma via the BTG2/PI3K/AKT axis.

Accumulating studies have indicated that exosomal microRNAs (miRNAs/miRs) can mediate clear cell renal cell carcinoma (ccRCC) at the early stage, but the mechanisms remain to be specified. Here, we investigated the mechanism of exosomal miR-15a in ccRCC. After successful isolation of exosomes from RCC cells, we found that miR-15a was upregulated in ccRCC cells. Moreover, upregulation of miR-15a by pre-miR-15a promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition of ccRCC cells. A luciferase assay revealed that B-cell translocation gene 2 (BTG2) was a target gene of miR-15a and negatively correlated with miR-15a expression. BTG2 was poorly expressed in ccRCC, which reduced the proliferation of ccRCC cells. In addition, overexpression of BTG2 could reverse the promotive effects of miR-15a on ccRCC. Furthermore, BTG2 reduced PI3K/AKT pathway activity. Our results collectively indicated that exosomal miR-15a from RCC cells accelerated cell viability by downregulating BTG2 and promoting the activity of the PI3K/AKT signaling pathway. We demonstrated a novel mechanism by which exosomal miR-15a exerted pro-proliferatory effects on ccRCC, highlighting the potential of exosomal miR-15a as a target for ccRCC prognosis.

hsa­miR­15a­5p inhibits colon cell carcinoma via targeting CCND1.

Colon carcinoma is one of the most common cancers worldwide. Epidemiological studies have revealed that colon cancer is the third leading cause of cancer­related deaths, which is due to the increased incidence and mortality rates. However, the treatment strategies for colon cancer remain unsatisfactory for patients, especially for those with advanced or recurrent colon cancer. Dysregulated microRNAs (miRNAs) are considered to influence tumor development and metastasis. However, the molecular mechanism through which miRNAs affect cancer progression is not yet completely understood. The aim of the present study was to investigate the expression levels of has­miR­15a­5p and its molecular mechanism in colon cell carcinoma. In the present study, the expression levels of hsa­miR­15a­5p were found to be decreased in colon tumor tissues and cancer cell lines. Hsa­miR­15a­5p overexpression inhibited colon cell proliferation and migration. Mechanistically, the G1/S­specific cyclin­D1 (CCND1) gene was predicted as a target of hsa­miR­15a­5p, as evidenced by bioinformatics and dual­luciferase reporter assay analyses. CCND1 overexpression significantly increased the progression of colon cancer. Furthermore, CCND1 was demonstrated to mediate the effects of hsa­miR­15a­5p on colon cancer cells. The present study demonstrated that hsa­miR­15a­5p alleviated the proliferation, migration and invasion of colon cancer by targeting the CCND1 gene, which represents a potential molecular target for the diagnosis and treatment of colon cancer.

Circular RNA SLC26A4 regulates the maturation of microRNA-15a in non-small cell lung cancer cells.

To the best of our knowledge, the oncogenic role of circular RNA solute carrier family 26 member 4 (circSLC26A4) has only been reported in cervical cancer, while its role in non-small cell lung cancer (NSCLC) is unknown. The present study explored the involvement of circSLC26A4 in NSCLC. NSCLC tissues and paired adjacent non-tumor tissues were collected from 64 patients with NSCLC. The expression levels of circSLC26A4, mature microRNA-15a (miR-15a) and miR-15a precursor in these tissues were determined by reverse transcription-quantitative PCR (RT-qPCR). NSCLC cells were transfected with pcDNA3.1-circSLC26A4 vector to overexpress circSLC26A4, followed by the measurement of the expression levels of mature miR-15a and miR-15a precursor using RT-qPCR. Cell proliferation was analyzed using a Cell Counting Kit-8 assay. circSLC26A4 expression was upregulated in NSCLC tissues, and its high expression was significantly associated with poor survival of patients with NSCLC. The expression levels of circSLC26A4 were correlated with the expression levels of mature miR-15a, but not the expression levels of miR-15a precursor in NSCLC tissues. In NSCLC cells, overexpression of circSLC26A4 was associated with downregulation of mature miR-15a expression, but not miR-15a precursor expression. A cell proliferation assay revealed that overexpression of circSLC26A4 reduced the inhibitory effects of overexpression of miR-15a on cell proliferation. Therefore, circSLC26A4 may suppress the maturation of miR-15a in NSCLC to inhibit cancer cell proliferation.

Exosomal DLX6-AS1 from hepatocellular carcinoma cells induces M2 macrophage polarization to promote migration and invasion in hepatocellular carcinoma through microRNA-15a-5p/CXCL17 axis.

BACKGROUND: Hepatocellular carcinoma (HCC) cells-secreted exosomes (exo) could stimulate M2 macrophage polarization and promote HCC progression, but the related mechanism of long non-coding RNA distal-less homeobox 6 antisense 1 (DLX6-AS1) with HCC-exo-mediated M2 macrophage polarization is largely ambiguous. Thereafter, this research was started to unearth the role of DLX6-AS1 in HCC-exo in HCC through M2 macrophage polarization and microRNA (miR)-15a-5p/C-X-C motif chemokine ligand 17 (CXCL17) axis. METHODS: DLX6-AS1, miR-15a-5p and CXCL17 expression in HCC tissues and cells were tested. Exosomes were isolated from HCC cells with overexpressed DLX6-AS1 and co-cultured with M2 macrophages. MiR-15a-5p/CXCL17 down-regulation assays were performed in macrophages. The treated M2 macrophages were co-cultured with HCC cells, after which cell migration, invasion and epithelial mesenchymal transition were examined. The targeting relationships between DLX6-AS1 and miR-15a-5p, and between miR-15a-5p and CXCL17 were explored. In vivo experiment was conducted to detect the effect of exosomal DLX6-AS1-induced M2 macrophage polarization on HCC metastasis. RESULTS: Promoted DLX6-AS1 and CXCL17 and reduced miR-15a-5p exhibited in HCC. HCC-exo induced M2 macrophage polarization to accelerate migration, invasion and epithelial mesenchymal transition in HCC, which was further enhanced by up-regulated DLX6-AS1 but impaired by silenced DLX6-AS1. Inhibition of miR-15a-5p promoted M2 macrophage polarization to stimulate the invasion and metastasis of HCC while that of CXCL17 had the opposite effects. DLX6-AS1 mediated miR-15a-5p to target CXCL17. DLX6-AS1 from HCC-exo promoted metastasis in the lung by inducing M2 macrophage polarization in vivo. CONCLUSION: DLX6-AS1 from HCC-exo regulates CXCL17 by competitively binding to miR-15a-5p to induce M2 macrophage polarization, thus promoting HCC migration, invasion and EMT.

Assessment of MicroRNA-15a and MicroRNA-16-1 Salivary Level in Oral Squamous Cell Carcinoma Patients.

BACKGROUND: Squamous Cell Carcinoma (SCC) includes more than 90% of malignancies of the oral cavity. Early diagnosis could effectively improve patients' quality of life and treatment outcomes of oral cancers. MicroRNAs as non-encoding genes have great potential to initiate or suppress cancer progression. Recent studies have shown that disruption of micro-RNA regulation is a common occurrence in cancers. OBJECTIVE: This study set out to evaluate the expression of microRNA-15a (miR-15a) and microRNA- 16-1 (miR-16-1) in the saliva of Oral Squamous Cell Carcinoma (OSCC) patients in comparison with a healthy control group. METHODS: This case-control study was performed on fifteen patients with OSCC and fifteen healthy volunteers as the control group. A 5 ml of non-stimulating whole saliva was collected by spitting method from patients and controls and stored at -70°C. The expression of miR-15a and miR-16-1 was investigated using quantitative Reverse-Transcription Polymerase Chain Reaction (RT-qPCR). RESULTS: MiR-15a and miR-16-1 were downregulated in OSCC patients compared with the control group (p<0.001). The sensitivity of miR-15a and miR-16-1 in differentiating OSCC patients from healthy individuals was 93.3% and 86.67%, respectively, and their specificity was 86.67% and 92.33%, respectively. The diagnostic accuracy of miR-15a was 90%, and miR-16-1 was 93.3%. CONCLUSION: The present study showed a decrease in the relative expression of miR-15a and miR-16-1 in OSCC patients compared with healthy individuals. It is probable to introduce salivary values of miR-15a and miR-16-1 as a non-invasive tool for early detection of OSCC. Decreased expression of miR-15a and miR-16-1 in OSCC indicates the possible effective role of these genes in OSCC etiopathogenesis.

MicroRNA-15a-5p inhibits endometrial carcinoma proliferation, invasion and migration via downregulation of VEGFA and inhibition of the Wnt/ß-catenin signaling pathway.

Endometrial carcinoma (EC) is one of the most common malignant gynecological tumors. Dysregulation of microRNAs (miRNAs/miRs) is frequently identified in human tumors, playing key regulatory roles in tumor growth and metastasis. The present study aimed to explore the functions and potential mechanisms of miR-15a-5p in EC progression. RT-qPCR was used to detect the expression levels of miR-15a-5p and vascular endothelial growth factor A (VEGFA) mRNA. Western blot analysis was performed to examine the expression of related proteins. Functional assays, including proliferation and Transwell assays were performed to determine the roles of miR-15a-5p in EC progression. TargetScan and luciferase reporter assays were used to explore the potential target genes of miR-15a-5p. The results revealed that miR-15a-5p was underexpressed in EC tissue samples in comparison with that in matched normal tissue samples. The expression level of miR-15a-5p was associated with the clinicopathologic characteristics of EC patients. Notably, both in vitro and in vivo assays revealed that miR-15a-5p upregulation significantly inhibited EC growth and metastasis. Furthermore, bioinformatics analysis and dual luciferase reporter assay indicated that VEGFA was a candidate target of miR-15a-5p. Mechanistic investigation revealed that miR-15a-5p inhibited EC development via regulation of Wnt/ß-catenin pathway and targeting of VEGFA. In summary, the present results demonstrated that miR-15a-5p could inhibit EC development and may serve as a promising therapeutic biomarker in EC.