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miR-335 and miR-34a are two microRNAs (miRNAs) usually downregulated in gastric cancer (GC). But, their exact regulative roles were not fully elucidated. In this study, we studied the association between miR-335 and/or miR-34a expression and overall survival of GC patients and explored the regulative role of miR-335 and -34a over survivin expression and GC cell growth and invasion. Fifty patients with GC were regularly followed up from 2011 to 2015. miRNA microarray was used to examine the expression trend of miRNAs in eight tumor tissue samples and adjacent normal tissue samples. The possible binding site between miR-335 and survivin messenger RNA (mRNA) was predicted using online database and verified using qRT-PCR, Western blot, and dual luciferase assay. The regulative role of miR-335 and miR-34a over GC cell growth, apoptosis, and invasion was studied using Cell Counting Kit-8 (CCK-8) assay, flow cytometry, and transwell assay, respectively. Among the GC patients, low miR-335 or miR-34a expression is associated with higher clinical stage and lymph node metastasis. Patients with low miR-335 or miR-34a had poor overall survival, while those with combined low miR-335 and miR-34a expression had even poorer overall survival. miR-335 can directly regulate survivin expression through binding to the 3'UTR, while miR-34a has indirect modulating effect. Both miR-335 and miR-34a could inhibit cell proliferation and invasion and enhance cell apoptosis. But, these effects are largely abrogated by overexpression of survivin without 3'UTR. Therefore, besides the targets identified in previous studies, miR-335 and miR-34a can also regulate GC cell growth, apoptosis, and invasion at least partly through survivin.

Study Design Animal and cellular models of spinal cord injury (SCI) were used to explore the role of miR-335 in regulating cell viability and apoptosis. Objective. To investigate the role and the target of miR-335 in SCI. Summary of Background. Based on analysis of the GSE19890 data set, miR-335 was identified as a downregulated microRNA (miRNAs) following SCI. Thus, this study investigated whether downregulation of miR-335 is important in the pathological process of SCI. Materials and Methods. The GSE19890 data set investigating the expression profiles of miRNAs after SCI was downloaded from the GEO database. GSE45006 and GSE4550 data sets were used to identify differentially expressed genes between normal samples and SCI samples. The targets of rno-miR-335 were predicted using the TargetScan database. An experimental model of SCI was established, and agomir-miR-335 was intrathecally injected into rats with SCI. Functional recovery was evaluated by assessment of Basso-Beattie-Bresnahan scores and spinal cord water content and performing hematoxylin-eosin staining. Apoptosis was estimated by TUNEL staining. The H2O2-treated PC12 cells were used as in vitro models of SCI. Cell viability and apoptosis were examined by cell counting kit-8 and flow cytometry. Caspase-3 expression was evaluated by immunofluorescence staining. Levels of miRNAs and mRNAs were measured by reverse transcriptase quantitative polymerase chain reaction. Western blotting was performed to measure Bcl-2, Bax, cleaved caspase-3, and specificity protein 1 (SP1) protein levels. Results. For in vivo studies, miR-335 was downregulated following SCI, and agomir-miR-335 delivery improved functional recovery through suppressing neuronal apoptosis by inactivating the SP1-Bax/Bcl-2/caspase-3 signaling. During in vitro analysis, miR-335 protected PC12 cells against H2O2-induced damage by negatively regulating the SP1-Bax/Bcl-2/caspase-3 signaling axis. Moreover, upregulation of SP1 abolished the apoptosis suppressive effects of miR-335 upregulation. Conclusion. MiR-335 ameliorates locomotor impairment in rats with SCI through the suppression of neuronal apoptosis by inactivating SP1-Bax/Bcl-2/caspase-3 signaling. [ABSTRACT FROM AUTHOR]

The rostral ventrolateral medulla (RVLM) is known as the vasomotor center that plays a crucial role in mediating the development of stress‐induced hypertension (SIH). MicroRNAs (miRNAs) are involved in many different biological processes and diseases. However, studies that evaluated the roles of miRNAs in the RVLM during SIH do not exist. Here, we performed RNA sequencing to explore the genome‐wide miRNA profiles in RVLM in an SIH rat model established by administering electric foot‐shocks and noises. The function of miRNAs in blood pressure regulation was determined in vivo via the intra‐RVLM microinjection of the agomir or antagomir. Furthermore, the underlying mechanisms of miRNAs on SIH were investigated through in vitro and in vivo experiments, like gain‐of‐function. We discovered 786 miRNA transcripts among which 4 were differentially expressed. The over‐expression of miR‐335 and miR‐674‐3p in RVLM dramatically increased the heart rate (HR), arterial blood pressure (ABP), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) levels of normotensive rats, whereas the knockdown of miR‐335 and miR‐674‐3p in RVLM markedly reduced the HR, ABP, SBP, DBP, and MAP levels of SIH rats. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation revealed that miR‐335 and miR‐674‐3p participated in regulating the development of SIH from different aspects, like apoptosis‐multiple species pathway. Sphk1, whose expression was markedly decreased in SIH, was identified as a novel target of miR‐335. MiR‐335 over‐expression substantially reduced the expression of Sphk1 and promoted neural apoptosis, and its inhibition had opposite effects. Re‐introduction of Sphk1 dramatically abrogated the apoptosis induced by miR‐335. This study provides the first systematic dissection of the RVLM miRNA landscape in SIH. MiR‐335 and miR‐674‐3p act as SIH promoters, and the identified miR‐335/Sphk1/apoptosis axis represents one of the possible mechanisms. These miRNAs can be exploited as potential targets for the molecular‐based therapy of SIH. [ABSTRACT FROM AUTHOR]

Recent development of integrative therapy against melanoma combines surgery, radiotherapy, targeted therapy, and immunotherapy; however, the clinical outcomes of advanced stage and recurrent melanoma are poor. As a skin cancer, melanoma is generally resistant to radiotherapy. Hence, there is an urgent need for evaluation of the mechanisms of radioresistance. The present study identified miR-335 as one of the differential expression of miRNAs in recurrent melanoma biopsies post-radiotherapy. The expression of miR-335 declined in melanoma tissues compared to the adjacent tissues. Moreover, miR-335 expression correlated with advanced stages of melanoma negatively. Consistent with the prediction of STARBASE and miRDB database, miR-335 targeted ROCK1 via binding with 3′-UTR of ROCK1 directly, resulting in attenuation of proliferation, migration, and radioresistance of melanoma cells. The authors validated that overexpression of miR-335 enhanced X-ray-induced tumor regression by B16 mouse models. Briefly, the present findings gained insights into miR-335/ROCK1-mediated radiosensitivity and provided a promising therapeutic strategy for improving radiotherapy against melanoma.

The modification of methyltransferase-like (METTL) enzymes plays important roles in various cellular responses by regulating microRNA expression. However, how m6A modification is involved in stress granule (SG) formation in the early stage of acute ischemic stroke by affecting the biogenesis processing of microRNAs remains unclear. Here, we established a middle cerebral artery occlusion (MCAO) model in rats and an oxygen-glucose deprivation/reperfusion (OGD/R) model in primary cortical neurons and PC12 cells to explore the potential mechanism between m6A modification and SG formation. The in vivo results showed that the level of infarction and apoptosis increased while SG formation decreased significantly within the ischemic cortex with improved reperfusion time after 2 h of ischemia. Consistent with the in vivo data, an inverse association between the apoptosis level and SG formation was observed in PC12 cells during the reperfusion period after 6 h of OGD stimulation. Both in vivo and in vitro results showed that the expression of METTL3 protein, m6A and miR-335 was significantly decreased with the reperfusion period. Overexpression of the METTL3 and METTL3 gene-knockdown in PC12 cells were achieved via plasmid transfection and CRISPR-Cas9 technology, respectively. Overexpression or knockdown of METTL3 in oxygen-glucose deprivation of PC12 cells resulted in functional maturation of miR-335, SG formation and apoptosis levels. In addition, we found that miR-335 enhanced SG formation through degradation of the mRNA of the eukaryotic translation termination factor (Erf1). In conclusion, we found that METTL3-mediated m6A methylation increases the maturation of miR-335, which promotes SG formation and reduces the apoptosis level of injury neurons and cells, and provides a potential therapeutic strategy for AIS. [ABSTRACT FROM AUTHOR]

Recent development of integrative therapy against melanoma combines surgery, radiotherapy, targeted therapy, and immunotherapy; however, the clinical outcomes of advanced stage and recurrent melanoma are poor. As a skin cancer, melanoma is generally resistant to radiotherapy. Hence, there is an urgent need for evaluation of the mechanisms of radioresistance. The present study identified miR-335 as one of the differential expression of miRNAs in recurrent melanoma biopsies post-radiotherapy. The expression of miR-335 declined in melanoma tissues compared to the adjacent tissues. Moreover, miR-335 expression correlated with advanced stages of melanoma negatively. Consistent with the prediction of STARBASE and miRDB database, miR-335 targeted ROCK1 via binding with 3′-UTR of ROCK1 directly, resulting in attenuation of proliferation, migration, and radioresistance of melanoma cells. The authors validated that overexpression of miR-335 enhanced X-ray-induced tumor regression by B16 mouse models. Briefly, the present findings gained insights into miR-335/ROCK1-mediated radiosensitivity and provided a promising therapeutic strategy for improving radiotherapy against melanoma. [ABSTRACT FROM AUTHOR]

Background: Cervical cancer (CC) ranks as the second most common malignancy in women, accounting for more two 2 million deaths every year in the world. Recently, circular RNAs (circRNAs) have been reported to regulate the progression of multiple human tumors; however, whether it involves in CC remains largely elusive. Materials and Methods: Two GEO circRNA expression profiles (GSE102686, GSE113696) were downloaded to analyze the differentially expressed circRNAs using bioinformatics methods. Expression of circ_103973, miR-335 and PPP6C in CC tissues and cell lines were examined by qRT-PCR. Cell apoptosis was assessed with PI/Annexin-V double staining followed by the analysis of flow cytometry. Cell proliferation was evaluated by MTT and colony formation assays. Interaction between circ_103973 and miR-335, as well as miR-335 and PPP6C, were verified by dual-luciferase reporter assay. Results: Circ_103973 was found to be highly expressed in both GSE102686 and GSE113696 datasets as well as in CC tissue samples and cell lines. Higher levels of circ_103973 were correlated to a worse outcome of CC patients. Knockdown of circ_103973 significantly promoted CC cell apoptosis and inhibited CC cell proliferation in vitro. Mechanistically, we demonstrated that circ_103973 served as a sponge of miR-335, which directly targeted PPP6C in CC cells. miR-335 was found to be decreased in CC, while PPP6C was found to be increased in CC. Moreover, anti-miR-335 could reverse the inhibitory effects of circ_103973 knockdown on CC cell proliferation, and this phenomenon could be blocked by si-PPP6C. Conclusion: Circ_103973 promoted CC cell proliferation in vitro by physically binding miR-335, which further targeted and regulated PPP6C. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Previous studies have shown that miR-335 plays an anti-tumor role in several types of cancer. However, whether it is able to regulate the tumorigenesis of osteosarcoma (OS) has not been fully investigated. The present study was designed to study its potential role in regulating apoptosis of OS cells. MATERIALS AND METHODS: The expression of miR-335 in a total of 18 paired OS tumor tissues and adjacent non-cancerous tissues was measured by Real-time PCR, and its different expression in OS cell lines was also measured. The effect of miR-335 on apoptosis was measured by MTT assay, caspase-3 activity assay and TUNEL assay. The effect of survivin inhibition on apoptosis of OS cells was determined by MTT assay and western blot. Luciferase reporter assay and western blot were conducted to confirm the relationship between miR-335 and the 3’UTR of survivin mRNA. RESULTS: MiR-335 expression was found to be significantly downregulated in OS tumor tissues and OS cell lines. Overexpression of miR- 335 led to decreased cell viability and increased apoptosis. MiR-335 directly targeted the 3’UTR of survivin mRNA and suppressed survivin gene expression, and inhibition of survivin exhibited similar effects to miR-335 overexpression. CONCLUSIONS: MiR-335 might function as a tumor suppressor in OS, and downregulation of miR-335 in OS cells contributes to the decreased apoptotic potential of OS cells through derepression of survivin. [ABSTRACT FROM AUTHOR]

MicroRNAs are small non-coding RNAs that may also function as oncogenes and tumor-suppressor genes, as the abnormal expression of microRNAs is associated with various human tumors. However, the effect of miR-335 on the lung cancer cells remains unclear. The aim of the paper was to study the expression of miR335 in non-small cell lung cancer (NSCLC) and miR335's relation to the metastasis, invasion, and apoptosis in lung cancer cells A549 and H1299. qRT-PCR was used to identify the miR-335 expression. The effects of miR-335 on cell proliferation, apoptosis, and invasion were further analyzed. Luciferase reporter assay and Western blot were to verify Bcl-w and SP1 as potential major target genes of miR-335. Finally, the effect of Bcl-w on miR-335-induced cell survival was determined. Our results showed that miR-335 expression was significantly lower in NSCLC tissue, which was significantly associated with lymph node metastasis. In contrast to cells in blank and negative control groups, incidence of apoptosis was significantly higher ( P < 0.05) and the number of cells migrating through matrigel was significantly lower ( P < 0.05) in miR-335 mimics transfected group. Western blot and luciferase reporter assay demonstrated that miR-335 could bind to the putative binding sites in Bcl-w (or SP1) mRNA 3′-untranslated region to visibly lower the expression of Bcl-w (or SP1). The introduction of Bcl-w cDNA without 3′-untranslated region abrogated miR-335-induced cell survival. These results indicated that upregulation of miR-335 can simultaneously suppress the invasiveness and promote apoptosis of lung cancer cell A549 and H1299 by targeting Bcl-w and SP1. Therefore, miR-335 may be a potential therapeutic target in NSCLC treatment. [ABSTRACT FROM AUTHOR]

Abstract: Activation and migration of resident stellate cells (HSCs) within the hepatic space of Disse play an important role in hepatic fibrosis, which accounts for the increased numbers of activated HSCs in areas of inflammation during hepatic fibrosis. Currently, microRNAs have been found to play essential roles in HSC differentiation, proliferation, apoptosis, fat accumulation and collagen production. However, little is known about microRNA mediated HSC activation and migration. In this study, the miRNA expression profiles of quiescent HSCs, partially activated HSCs and fully activated HSCs were compared in pairs. Gene ontology (GO) and GO-Map network analysis indicated that the activation of HSCs was regulated by microRNAs. Among them miR-335 was confirmed to be significantly reduced during HSC activation by qRT-PCR, and restoring expression of miR-335 inhibited HSC migration and reduced α-SMA and collagen type I. Previous study revealed that tenascin-C (TNC), an extracellular matrix glycoprotein involved in cell migration, might be a target of miR-335. Therefore, we further studied the TNC expression in miR-335 over-expressed HSCs. Our data showed that exogenous TNC could enhance HSC migration in vitro and miR-335 restoration resulted in a significant inhibition of TNC expression. These results demonstrated that miR-335 restoration inhibited HSC migration, at least in part, via downregulating the TNC expression. [Copyright &y& Elsevier]

The fetal brain is sensitive to a variety of teratogens, including ethanol. We showed previously that ethanol induced mitosis and stem cell maturation, but not death, in fetal cerebral cortex-derived progenitors. We tested the hypothesis that micro-RNAs (miRNAs) could mediate the teratogenic effects of ethanol in a fetal mouse cerebral cortex-derived neurosphere culture model. Ethanol, at a level attained by alcoholics, significantly suppressed the expression of four miRNAs, miR-21, -335, -9, and -153, whereas a lower ethanol concentration, attainable during social drinking, induced miR-335 expression. A GABAA receptor-dependent mechanism mediated miR-21, but not miR-335 suppression, suggesting that divergent mechanisms regulate ethanol-sensitive miRNAs. Antisense-mediated suppression of miR-21 expression resulted in apoptosis, suggesting that miR-21 is an antiapoptotic factor. miR-335 knockdown promoted cell proliferation and prevented death induced by concurrently suppressing miR-21, indicating that miR-335 is a proapoptotic, antimitogenic factor whose actions are antagonistic to miR-21. Computational analyses identified two genes, Jagged-1, a Notch-receptor ligand, and embryonic-lethal abnormal vision, Drosophila-like 2 (ELAVL2), a brain-specific regulator of RNA stability, as presumptive targets of three of four ethanol-sensitive micro-RNAs. Combined knockdown of miR-335, -21, and -153 significantly increased Jagged-1 mRNA. Furthermore, ethanol induced both Jagged-1 and ELAVL2 mRNA. The collective suppression of micro-RNAs is consistent with ethanol induction of cell cycle and neuroepithelial maturation in the absence of apoptosis. These data identify a role for micro-RNAs as epigenetic intermediaries, which permit teratogens to shape complex, divergent developmental processes, and additionally demonstrate that coordinately regulated miRNAs exhibit both functional synergy and antagonism toward each other. [ABSTRACT FROM AUTHOR]

Keywords: melanoma; ionizing radiation; resistance; apoptosis; miR-335; ROCK1 EN melanoma ionizing radiation resistance apoptosis miR-335 ROCK1 N.PAG N.PAG 1 02/08/21 20210204 NES 210204 In the published article, there was an error regarding the affiliations for Peng Shen. Melanoma, ionizing radiation, resistance, apoptosis, miR-335, ROCK1. [Extracted from the article]