Effect of the interaction between MiR‐200b‐3p and DNMT3A on cartilage cells of osteoarthritis patients

The aim of this research is to explore the effect of miR‐200b‐3p targeting DNMT3A on the proliferation and apoptosis of osteoarthritis (OA) cartilage cells. Quantitative RT‐PCR was performed to analyse the expression of miR‐200b‐3p, DNMT3A, MMP1, MMP3, MMP9, MMP13 and COL II in normal and OA cartilage tissues. The dual‐luciferase reporter assay and Western blot assay were conducted to confirm the targeting relationship between miR‐200b‐3p and DNMT3A. We also constructed eukaryotic expression vector to overexpress miR‐200b‐3p and DNMT3A. We detected the expression level of MMPs and COL II in stable transfected cartilage cells using RT‐PCR and Western blot. Cell proliferation and apoptosis were evaluated using the MTS, pellet culture and Hoechst 33342 staining method. Finally, we explored the effect of miR‐200b‐3p targeting DNMT3A on the proliferation and apoptosis of OA cartilage cells. The results of RT‐PCR indicated that both miR‐200b‐3p and COL II were down‐regulated in OA cartilage tissues, while the expression of DNMT3A and MMPs was up‐regulated in OA cartilage tissues. The expressions of DNMT3A, MMPs and COL II detected by Western blot showed the same trend of the results of RT‐PCR. The dual‐luciferase reporter assay and Western blot assay confirmed the targeting relationship between miR‐200b‐3p and DNMT3A. In overexpressed miR‐200b‐3p cartilage cells, DNMT3A and MMPs were significantly down‐regulated, COL II was significantly up‐regulated, cell viability was enhanced and apoptosis rate was decreased (P < 0.05). In overexpressed DNM3T cartilage cells, MMPs were significantly up‐regulated, COL II was significantly down‐regulated, cell viability was weakened and apoptosis rate was increased (P < 0.05). MiR‐200b‐3p inhibited the secretion of MMPs, promoted the synthesis of COL II and enhanced the growth and proliferation of OA cartilage cells through inhibiting the expression of DNMT3A.     

MicroRNA‐30a ameliorates hepatic fibrosis by inhibiting Beclin1‐mediated autophagy

We explored the role of microRNA‐30a (miR‐30a) and the mechanism involved in hepatic fibrosis. MiR‐30a overexpression was achieved by miR‐30a mimics transfection in hepatic stellate cells (HSCs) (HSC‐T6, LX‐2), and miR‐30a agomir (ago‐miR‐30a) treatment in mice. MiR‐30a levels were measured using TaqMan miRNA assay system, and the localization of miR‐30a was detected by fluorescence in situ hybridization (FISH). The interaction of miR‐30a and Beclin1 was confirmed by dual‐luciferase reporter assay. Autophagic flux was analysed using tandem mRFP‐GFP‐LC3 fluorescence microscopy, electron microscopy and Western blot of LC3‐II/I ratio. MiR‐30a was notably down‐regulated in activated HSCs and LX‐2‐exosomes induced by TGF‐β1; overexpression of miR‐30a down‐regulated extracellular matrix (ECM), such as α‐SMA, TIMP‐1, and Collagen I expression, and suppressed cell viability in HSCs. MiR‐30a was significantly down‐regulated in hepatic fibrosis mice and overexpression of miR‐30a prevented BDL‐induced fibrogenesis, concomitant with the down‐regulation of ECM. MiR‐30a inhibited HSCs autophagy and increased lipid accumulation in HSCs and in mice fibrotic hepatic tissues. MiR‐30a inhibited its downstream effector of Beclin1 by direct targeting its 3′‐UTR region. Moreover, Knock‐down of Beclin1 by small interfering RNA (siRNA) inhibited HSC autophagy and activation in LX‐2 cells. In conclusion, miR‐30a is down‐regulated in hepatic fibrosis models and its overexpression prevents liver fibrogenesis by directly suppressing Beclin1‐mediated autophagy; therefore, miR‐30a may be a new potential therapeutic target for controlling hepatic fibrosis.     

MiR‐19a Affects Hepatocyte Autophagy via Regulating lncRNA NBR2 and AMPK/PPARα in D‐GalN/Lipopolysaccharide‐Stimulated Hepatocytes

This study aims to evaluate the potential involvement and regulatory mechanism of miR‐19a in hepatocytes autophagy of acute liver failure (ALF). The in vitro hepatocytes injury model of primary hepatocyte and hepatocytes line HL‐7702 was established by D‐galactosamine (D‐GalN) and lipopolysaccharide (LPS) co‐treatment. Relative expression level of miR‐19a and NBR2 was determined by qRT‐PCR. Protein expression of AMPK/PPARα and autophagy‐related gene was determined by Western blot. In hepatic tissue of 20 ALF patients and D‐GalN/LPS‐stimulated hepatocytes, miR‐19a was upregulated and NBR2 was downregulated. D‐GalN/LPS stimulation caused the inactivation of AMPK/PPARα signaling and the decrease of autophagy‐related LC3‐II/LC3‐I ratio and beclin‐1 expression in hepatocytes. The expression of both AMPK/PPARα and NBR2 were negatively controlled by miR‐19a overexpression or knockdown. Moreover, both NBR2 and PPARα were targeted regulated by miR‐19a according to luciferase reporter assay. In D‐GalN/LPS‐stimulated hepatocytes, AMPK activation promoted PPARα expression. AMPK inactivation inhibited the pro‐autophagy effect of miR‐19a and caused the decrease of LC3‐II/LC3‐I ratio and beclin‐1 expression. PPARα activation abrogated the anti‐autophagy effect of miR‐19a mimic and caused the increase of LC3‐II/LC3‐I ratio and beclin‐1 expression. NBR2 knockdown reversed the anti‐autophagy impact of miR‐19a inhibitor and caused the decrease of LC3‐II/LC3‐I ratio and beclin‐1 expression. In summary, our data suggested that miR‐19a negatively controlled the autophagy of hepatocytes attenuated in D‐GalN/LPS‐stimulated hepatocytes via regulating NBR2 and AMPK/PPARα signaling. J. Cell. Biochem. 119: 358–365, 2018. © 2017 Wiley Periodicals, Inc.     

miRNA‐182/Deptor/mTOR axis regulates autophagy to reduce intestinal ischaemia/reperfusion injury

It had been reported miR‐182 was down‐regulated after intestinal ischaemia/reperfusion (I/R) damage. However, its role and potential mechanisms are still unknown. This study was aimed to elucidate the function of miR‐182 in intestinal I/R injury and the underlying mechanisms. The model of intestinal injury was constructed in wild‐type and Deptor knockout (KO) mice. Haematoxylin‐eosin staining, Chiu's score and diamine oxidase were utilized to detect intestinal damage. RT‐qPCR assay was used to detected miR‐182 expression. Electronic microscopy was used to detect autophagosome. Western blot was applied to detect the expression of Deptor, S6/pS6, LC3‐II/LC3‐I and p62. Dual‐luciferase reporter assay was used to verify the relationship between miR‐182 and Deptor. The results showed miR‐182 was down‐regulated following intestinal I/R. Up‐regulation of miR‐182 reduced intestinal damage, autophagy, Deptor expression and enhanced mTOR activity following intestinal I/R. Moreover, suppression of autophagy reduced intestinal damage and inhibition of mTOR by rapamycin aggravated intestinal damage following intestinal I/R. Besides, damage of intestine was reduced and mTOR activity was enhanced in Deptor KO mice. In addition, Deptor was the target gene of miR‐182 and was indispensable for the protection of miR‐182 on intestine under I/R condition. Together, our research implicated up‐regulation of miR‐182 inhibited autophagy to alleviate intestinal I/R injury via mTOR by targeting Deptor.     

Up‐regulation of miR‐10b‐3p promotes the progression of hepatocellular carcinoma cells via targeting CMTM5

In this study, we investigated how miR‐10b‐3p regulated the proliferation, migration, invasion in hepatocellular carcinoma (HCC) at both in vitro and in vivo levels. CMTM5 was among the differentially expressed genes (data from TCGA). The expression of miR‐10b‐3p and CMTM5 was detected by qRT‐PCR and Western blot (WB). TargetScan was used to acquire the binding sites. Dual‐luciferase reporter gene assay was used to verify the direct target relationship between miR‐10b‐3p and CMTM5. WB analysis proved that miR‐10b‐3p suppressed CMTM5 expression. Furthermore, proliferation, invasion and migration of HCC cells were measured by MTT assay, colony formation assay, transwell assay and wound‐healing assay, respectively. Kaplan‐Meier plotter valued the overall survival of CMTM5. Finally, xenograft assay was also conducted to verify the effects of miR‐10b‐3p/CMTM5 axis in vivo. Up‐regulation of miR‐10b‐3p and down‐regulation of CMTM5 were detected in HCC tissues and cell lines. CMTM5 was verified as a target gene of miR‐10b‐3p. The overexpression of CMTM5 contributed to the suppression of the proliferative, migratory and invasive abilities of HCC cells. Moreover, the up‐regulation of miR‐10b‐3p and down‐regulation of CMTM5 were observed to be associated with worse overall survival. Lastly, we have confirmed the carcinogenesis‐related roles of miR‐10b‐3p and CMTM5 in vivo. We concluded that the up‐regulation of miR‐10b‐3p promoted the progression of HCC cells via targeting CMTM5.     

LncRNA MEG3 inhibits the progression of prostate cancer by modulating miR‐9‐5p/QKI‐5 axis

This study was designed to detecting the influences of lncRNA MEG3 in prostate cancer. Aberrant lncRNAs expression profiles of prostate cancer were screened by microarray analysis. The qRT‐PCR and Western blot were employed to investigating the expression levels of lncRNA MEG3, miR‐9‐5p and QKI‐5. The luciferase reporter assay was utilized to testifying the interactions relationship among these molecules. Applying CCK‐8 assay, wound healing assay, transwell assay and flow cytometry in turn, the cell proliferation, migration and invasion abilities as well as apoptosis were measured respectively. LncRNA MEG3 was a down‐regulated lncRNA in prostate cancer tissues and cells and could inhibit the expression of miR‐9‐5p, whereas miR‐9‐5p down‐regulated QKI‐5 expression. Overexpressed MEG3 and QKI‐5 could decrease the abilities of proliferation, migration and invasion in prostate cancer cells effectively and increased the apoptosis rate. On the contrary, miR‐9‐5p mimics presented an opposite tendency in prostate cancer cells. Furthermore, MEG3 inhibited tumour growth and up‐regulated expression of QKI‐5 in vivo. LncRNA MEG3 was a down‐regulated lncRNA in prostate cancer and impacted the abilities of cell proliferation, migration and invasion, and cell apoptosis rate, this regulation relied on regulating miR‐9‐5p and its targeting gene QKI‐5.     

miR‐203 inhibits proliferation of HCC cells by targeting survivin

To validate whether down‐regulation of microRNA‐203 (miR‐203) in hepatocellular carcinoma (HCC) is involved in HCC progression by targeting survivin. MiR‐203 mimics was transfected into HepG2 cells to enhance miR‐203 expression, and miR‐203 inhibitor was transfected into HepG2 cells to inhibit miR‐203 expression. The effect of up‐regulation and down‐regulation of miR‐203 on survivin expression of HepG2 cells was evaluated using Western blot assay. The effect of miR‐203 or survivin expression on the proliferation of HepG2 cells was detected using the CKK‐8 assay. Over‐expression of miR‐203 significantly inhibited the expression of survivin in HepG2 cells (p < 0·05), and down‐expression of miR‐203 significantly promoted the expression of survivin in HepG2 cells (p < 0·05). Both over‐expression of miR‐203 and down‐regulation of survivin suppressed proliferation of HepG2 cells significantly compared with negative control. Low expression of miR‐203 contributes to the progression of HCC via targeting survivin. Copyright © 2012 John Wiley & Sons, Ltd.     

Derepression of c‐Fos caused by MicroRNA‐139 down‐regulation contributes to the metastasis of human hepatocellular carcinoma

This study investigates whether the anti‐metastasis effect of microRNA‐139 (miR‐139) on hepatocellular carcinoma (HCC) is mediated through regulating c‐fos expression. The expression levels of miR‐139 and c‐fos in human HCC cell sublines with high (MHCC97H) and low (MHCC97L) spontaneous metastatic potentials were quantified using QPCR or Western blot. miR‐139 mimics was transfected into MHCC97H cells to overexpress miR‐139, and miR‐139 inhibitor was transfected into MHCC97L cells to down‐express miR‐139. The effect of overexpression or down‐expression of miR‐139 on c‐fos expression of MHCC97H and MHCC97L cells was evaluated using QPCR and Western blot. The 3′ untranslated region segments of FOS containing the miR‐139 binding sites were amplified by PCR, and the luciferase activity in the transfected cells was assayed. In comparison with the expression level of miR‐139 in MHCC97L cells, the expression level in MHCC97H cells was significantly decreased, whereas c‐Fos was significantly up‐regulated in MHCC97H. The overexpression of miR‐139 significantly inhibited the expression of c‐fos in MHCC97H cells, and the down‐expression of miR‐139 significantly promoted the expression of c‐fos in MHCC97L cells. miR‐139 suppressed the luciferase activity of the pGL‐FOS by approximately 40% compared with the negative control. In vitro cell migration analysis demonstrated that depletion of c‐fos or overexpression of miR‐139 in MHCC97H cells reduced cell migration, whereas overexpression of c‐fos or depletion of miR‐139 in MHCC97L cells increased cell migration. Thus, we got the conclusion that miR‐139 expression is down‐regulated in human HCC cell sublines with high spontaneous metastatic potentials (MHCC97H). Derepression of c‐Fos caused by miR‐139 down‐regulation contributes to the metastasis of HCC. Copyright © 2012 John Wiley & Sons, Ltd.     

Atractylenolide II reverses the influence of lncRNA XIST/miR‐30a‐5p/ROR1 axis on chemo‐resistance of colorectal cancer cells

This investigation was conducted to elucidate whether atractylenolide II could reverse the role of lncRNA XIST/miR‐30a‐5p/ROR1 axis in modulating chemosensitivity of colorectal cancer cells. We totally collected 294 pairs of colorectal cancer tissues and adjacent normal tissues and also purchased colorectal cancer cell lines and human embryonic kidney cell line. 5‐fluorouracil, cisplatin, mitomycin and adriamycin were designated as the chemotherapies for colorectal cell lines, and atractylenolides were arranged as the Chinese drug. The expressions of XIST, miR‐30a‐5p and ROR1 were quantified with aid of qRT‐PCR or Western blot, and luciferase reporter gene assay was implemented to determine the relationships among XIST, miR‐30a‐5p and ROR1. Our results demonstrated that XIST and ROR1 expressions were dramatically up‐regulated, yet miR‐30a‐5p expression was down‐regulated within colorectal cancer tissues (P < 0.05). The overexpressed XIST and ROR1, as well as under‐expressed miR‐30a‐5p, were inclined to promote viability and proliferation of colorectal cells under the influence of chemo drugs (P < 0.05). In addition, XIST could directly target miR‐30a‐5p, and ROR1 acted as the targeted molecule of miR‐30a‐5p. Interestingly, atractylenolides not only switched the expressions of XIST, miR‐30a‐5p and ROR1 within colorectal cancer cells but also significantly intensified the chemosensitivity of colorectal cancer cells (P < 0.05). Finally, atractylenolide II was discovered to slow down the viability and proliferation of colorectal cancer cells (P < 0.05). In conclusion, the XIST/miR‐30a‐5p/ROR1 axis could be deemed as pivotal markers underlying colorectal cancer, and administration of atractylenolide II might improve the chemotherapeutic efficacy for colorectal cancer.     

Toll‐like receptor signalling cross‐activates the autophagic pathway to restrict Salmonella Typhimurium growth in macrophages

It has been long recognised that activation of toll‐like receptors (TLRs) induces autophagy to restrict intracellular bacterial growth. However, the mechanisms of TLR‐induced autophagy are incompletely understood. Salmonella Typhimurium is an intracellular pathogen that causes food poisoning and gastroenteritis in humans. Whether TLR activation contributes to S. Typhimurium‐induced autophagy has not been investigated. Here, we report that S. Typhimurium and TLRs shared a common pathway to induce autophagy in macrophages. We first showed that S. Typhimurium‐induced autophagy in a RAW264.7 murine macrophage cell line was mediated by the AMP‐activated protein kinase (AMPK) through activation of the TGF‐β‐activated kinase (TAK1), a kinase activated by multiple TLRs. AMPK activation led to increased phosphorylation of Unc‐51‐like autophagy activating kinase (ULK1) at S317 and S555. ULK1 phosphorylation at these two sites in S. Typhimurium‐infected macrophages overrode the inhibitory effect of mTOR on ULK1 activity due to mTOR‐mediated ULK1 phosphorylation at S757. Lipopolysaccharide (LPS), flagellin, and CpG oligodeoxynucleotide, which activate TLR4, TLR5, and TLR9, respectively, increased TAK1 and AMPK phosphorylation and induced autophagy in RAW264.7 cells and in bone marrow‐derived macrophages. However, LPS was unable to induce TAK1 and AMPK phosphorylation and autophagy in TLR4‐deficient macrophages. TAK1 and AMPK‐specific inhibitors blocked S. Typhimurium‐induced autophagy and xenophagy and increased the bacterial growth in RAW264.7 cells. These observations collectively suggest that activation of the TAK1–AMPK axis through TLRs is essential for S. Typhimurium‐induced autophagy and that TLR signalling cross‐activates the autophagic pathway to clear intracellular bacteria.     

Down‐regulation of miR‐10a‐5p in synoviocytes contributes to TBX5‐controlled joint inflammation

MicroRNAs are considered to play critical roles in the pathogenesis of human inflammatory arthritis, including rheumatoid arthritis (RA). The purpose of this study was to determine the relationship between miR‐10a‐5p and TBX5 in synoviocytes and evaluate their contribution to joint inflammation. The expression of miR‐10a‐5p and TBX5 in the synovium of RA and human synovial sarcoma cell line SW982 stimulated by IL‐1β was determined by RT‐qPCR and Western blotting. The direct interaction between miR‐10a‐5p and TBX5 3′UTR was determined by dual‐luciferase reporter assay in HeLa cells. Mimics and inhibitors of miR‐10a‐5p were transfected into SW982 cells. TBX5 was overexpressed by plasmid transfection or knocked down by RNAi. Proinflammatory cytokines and TLR3 and MMP13 expressions were determined by RT‐qPCR and Western blotting. Down‐regulated expression of miR‐10a‐5p and up‐regulation of TBX5 in human patients with RA were found compared to patients with OA. IL‐1β could reduce miR‐10a‐5p and increase TBX5 expression in SW982 cells in vitro. The direct target relationship between miR‐10a‐5p and 3′UTR of TBX5 was confirmed by luciferase reporter assay. Alterations of miR‐10‐5p after transfection with its mimic and inhibitor caused the related depression and re‐expression of TBX5 and inflammatory factors in SW982 cells. Overexpression of TBX5 after pCMV3‐TBX5 plasmid transfection significantly promoted the production of TLR3, MMP13 and various inflammatory cytokines, while this effect was rescued after knocking down of TBX5 with its specific siRNA. We conclude that miR‐10a‐5p in a relation with TBX5 regulates joint inflammation in arthritis, which would serve as a diagnostic and therapeutic target for RA treatment.     

Curcumin reinforces MSC‐derived exosomes in attenuating osteoarthritis via modulating the miR‐124/NF‐kB and miR‐143/ROCK1/TLR9 signalling pathways

Curcumin treatment was reported to delay the progression of OA, but its underlying mechanism remains unclear. In this study, we aimed to investigate the molecular mechanism underlying the role of curcumin in OA treatment. Accordingly, by conducting MTT and flow cytometry assays, we found that the exosomes derived from curcumin‐treated MSCs helped to maintain the viability while inhibiting the apoptosis of model OA cells. Additionally, quantitative real‐time PCR and Western blot assays showed that the exosomes derived from curcumin‐treated MSCs significantly restored the down‐regulated miR‐143 and miR‐124 expression as well as up‐regulated NF‐kB and ROCK1 expression in OA cells. Mechanistically, curcumin treatment decreased the DNA methylation of miR‐143 and miR‐124 promoters. In addition, the 3’ UTRs of NF‐kB and ROCK1 were proven to contain the binding sites for miR‐143 and miR‐124, respectively. Therefore, the up‐regulation of miR‐143 and miR‐124 in cellular and mouse OA models treated with exosomes remarkably restored the normal expression of NF‐kB and ROCK1. Consequently, the progression of OA was attenuated by the exosomes. Our results clarified the molecular mechanism underlying the therapeutic role of MSC‐derived exosomes in OA treatment.     

ACE2‐EPC‐EXs protect ageing ECs against hypoxia/reoxygenation‐induced injury through the miR‐18a/Nox2/ROS pathway

Oxidative stress is one of the mechanisms of ageing‐associated vascular dysfunction. Angiotensin‐converting enzyme 2 (ACE2) and microRNA (miR)‐18a have shown to be down‐regulated in ageing cells. Our previous study has shown that ACE2‐primed endothelial progenitor cells (ACE2‐EPCs) have protective effects on endothelial cells (ECs), which might be due to their released exosomes (EXs). Here, we aimed to investigate whether ACE2‐EPC‐EXs could attenuate hypoxia/reoxygenation (H/R)‐induced injury in ageing ECs through their carried miR‐18a. Young and angiotensin II‐induced ageing ECs were subjected to H/R and co‐cultured with vehicle (medium), EPC‐EXs, ACE2‐EPCs‐EXs, ACE2‐EPCs‐EXs + DX600 or ACE2‐EPCs‐EXs with miR‐18a deficiency (ACE2‐EPCs‐EXs^{anti‐miR‐18a}). Results showed (1) ageing ECs displayed increased senescence, apoptosis and ROS production, but decreased ACE2 and miR‐18a expressions and tube formation ability; (2) under H/R condition, ageing ECs showed higher rate of apoptosis, ROS overproduction and nitric oxide reduction, up‐regulation of Nox2, down‐regulation of ACE2, miR‐18a and eNOS, and compromised tube formation ability; (3) compared with EPC‐EXs, ACE2‐EPC‐EXs had better efficiencies on protecting ECs from H/R‐induced changes; (4) The protective effects were less seen in ACE2‐EPCs‐EXs + DX600 and ACE2‐EPCs‐EXs^{anti‐miR‐18a} groups. These data suggest that ACE‐EPCs‐EXs have better protective effects on H/R injury in ageing ECs which could be through their carried miR‐18a and subsequently down‐regulating the Nox2/ROS pathway.     

人参根提取物增强巨噬细胞RAW264.7的自噬水平并提高其增殖和吞噬能力

研究人参根提取物对巨噬细胞RAW264.7的增殖能力、吞噬能力和自噬水平的影响以及其相关性.用细胞计数试剂(CCK-8)检测不同浓度的人参根以及加入对巨噬细胞RAW264.7增殖的影响;采用中性红吞噬实验检测人参根提取物对巨噬细胞吞噬活性的影响;采用吖啶橙染色法(AO染色法)检测自噬体的形成;采用免疫印迹法(Weste...     

MiR‐133a‐3p Inhibits Oral Squamous Cell Carcinoma (OSCC) Proliferation and Invasion by Suppressing COL1A1

The aim of our study was to investigate the effects of miR‐133a‐3p on human oral squamous cell carcinoma (OSCC) cells by regulating gene COL1A1. OSCC tissues, adjacent tongue epithelial tissues, the immortalized oral epithelial cell line HIOEC, and OSCC cell lines (CAL‐27, TCA‐8113, SCC‐4, SCC‐9, and SCC‐15) were used in this research. Quantitative real‐time PCR (RT‐qPCR) was employed to determine the expression of miR‐133a‐3p and COL1A1. Dual luciferase reporter gene assay and Western blot were applied to verify the binding relationship between miR‐133a‐3p and COL1A1. Functional assays were also conducted in this study, including CCK‐8 assay, colony formation assay, flow cytometry analysis as well as Transwell assay. MiR‐133a‐3p was found low‐expressed both in OSCC tissues and cells lines compared with normal tissues and cell line, respectively, whereas COL1A1 was just the opposite. The over‐expression of miR‐133a‐3p or the down‐regulation of COL1A1 suppressed the proliferation, invasion, and mitosis of OSCC cells, whereas simultaneous down‐regulation of miR‐133a‐3p and up‐regulation of COL1A1 led to no significant alteration of cell activities. MiR‐133a‐3p could inhibit the proliferation and migration of OSCC cells through directly targeting COL1A1 and reducing its expression. J. Cell. Biochem. 119: 338–346, 2018. © 2017 Wiley Periodicals, Inc.     

MiR‐139‐5p,miR‐940 and miR‐193a‐5p inhibit the growth of hepatocellular carcinoma by targeting SPOCK1

The study was aimed to screen out miRNAs with differential expression in hepatocellular carcinoma (HCC), and to explore the influence of the expressions of these miRNAs and their target gene on HCC cell proliferation, invasion and apoptosis. MiRNAs with differential expression in HCC were screened out by microarray analysis. The common target gene of these miRNAs (miR‐139‐5p, miR‐940 and miR‐193a‐5p) was screened out by analysing the target genes profile (acquired from Targetscan) of the three miRNAs. Expression levels of miRNAs and SPOCK1 were determined by quantitative real time polymerase chain reaction (qRT‐PCR). The target relationships were verified by dual luciferase reporter gene assay and RNA pull‐down assay. Through 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2‐H‐tetrazolium bromide,thiazolyl blue tetrazolium bromide (MTT) and transwell assays and flow cytometry, HCC cell viability, invasion and apoptosis were determined. In vivo experiment was conducted in nude mice to investigate the influence of three miRNAs on tumour growth. Down‐regulation of miR‐139‐5p, miR‐940 and miR‐193a‐5p was found in HCC. Overexpression of these miRNAs suppressed HCC cell viability and invasion, promoted apoptosis and inhibited tumour growth. SPOCK1, the common target gene of miR‐139‐5p, miR‐940 and miR‐193a‐5p, was overexpressed in HCC. SPOCK1 overexpression promoted proliferation and invasion, and restrained apoptosis of HCC cells. MiR‐139‐5p, miR‐940 and miR‐193a‐5p inhibited HCC development through targeting SPOCK1.     

MiR‐139‐5p inhibits the tumorigenesis and progression of oral squamous carcinoma cells by targeting HOXA9

Our study sought to clarify the effects of microRNA‐139‐5p (miR‐139‐5p) in the tumorigenesis and progression of oral squamous cell carcinoma (OSCC) by regulating HOXA9. MiR‐139‐5p and HOXA9 expression in OSCC tissues, tumour adjacent tissues, OSCC cells and normal cells were tested by qRT‐PCR. SAS and CAL‐27 cell lines were selected in among four OSCC cell lines and then transfected with miR‐139‐5p mimics, pEGFP‐HOXA9 and cotransfected with miR‐139‐5p mimics + pEGFP‐HOXA9. We used MTT, colony formation, transwell and wound healing assays to analyse cell viability, proliferation, invasion and migration. The target relationship between miR‐139‐5p and HOXA9 was verified by luciferase reporter assay and Western blot, respectively. MiR‐139‐5p was down‐regulated, whereas HOXA9 was up‐regulated in OSCC tissues and cells. The proliferation, invasion and migration ability of SAS and CAL‐27 cells in miR‐139‐5p mimics group were significantly weaker than those in the control group and the miR‐NC group (P < 0.01). MiR‐139‐5p can negatively regulate HOXA9. The proliferation, invasion and migration of SAS and CAL‐27 cells in the miR‐139‐5p mimics + pEGFP‐HOXA9 group were not significantly different from those in the blank control and negative control groups (P > 0.05). Our results indicated that miR‐139‐5p could directly inhibit HOXA9, which might be a potential mechanism in inhibiting the proliferation, invasiveness and migration of OSCC cells.     

LncRNA SNHG1 functions as a ceRNA to antagonize the effect of miR‐145a‐5p on the down‐regulation of NUAK1 in nasopharyngeal carcinoma cell

How lncRNA SNHG1 influences the aggressiveness of nasopharyngeal carcinoma cells as well as the underlying mechanism was studied. The lncRNA differences were analysed by GSE12452 gene microarray. The expression of SNHG1, MiR‐145‐5p and NUAK1 was identified by qRT‐PCR and western blot. Transfection was conducted to construct nasopharyngeal carcinoma cells with different expressions of SNHG1, miR‐145‐5p and NUAK1. Dual‐luciferase reporter assay was performed to explore the relationship between SNHG1, miR‐145‐5p and NUAK1. Wound‐healing assay and transwell invasion experiments were employed to study changes in cell migration capacity and cell invasion, respectively. Tumour xenografts were performed to observe lung metastasis of nude mice inoculated with transfected CNE cells. SNHG1 is highly expressed in nasopharyngeal carcinoma tissues and in cell lines. Down‐regulation of SNHG1 facilitated the expression of miR‐145‐5p and further suppressed the level of NAUK1 in CNE and HNE‐1 cells. Silencing of SNHG1, up‐regulation of miR‐145‐5p and inhibition of NAUK1 by relative transfection all attenuated the aggressiveness of CNE and HNE‐1 cells both in vivo and in vitro. Moreover, the impaired cell migration and invasion by SNHG1 siRNA could be rescued by cotransfection of miR‐145‐5p in CNE and HNE‐1 cells. LncRNA SNHG1 promoted the expression of NUAK1 by down‐regulating miR‐145‐5p and thus promoted the aggressiveness of nasopharyngeal carcinoma cells through AKT signalling pathway and induced epithelial‐mesenchymal transition (EMT).     

KITLG is a novel target of miR‐34c that is associated with the inhibition of growth and invasion in colorectal cancer cells

MiR‐34c is considered a potent tumour suppressor because of its negative regulation of multiple target mRNAs that are critically associated with tumorigenesis and metastasis. In the present study, we demonstrated a novel target of miR‐34c, KITLG, which has been implicated in colorectal cancer (CRC). First, we found a significant negative relationship between miR‐34c and KITLG mRNA expression levels in CRC cell lines, including HT‐29, HCT‐116, SW480 and SW620 CRC cell lines. In silico analysis predicted putative binding sites for miR‐34c in the 3′ untranslated region (3′UTR) of KITLG mRNA. A dual‐luciferase reporter assay further confirmed that KITLG is a direct target of miR‐34c. Then, the cell lines were infected with lentiviruses expressing miR‐34c or a miR‐34c specific inhibitor. Restoration of miR‐34c dramatically reduced the expression of KITLG mRNA and protein, while silencing of endogenous miR‐34c increased the expression of KITLG protein. The miR‐34c‐mediated down‐regulation of KITLG was associated with the suppression on proliferation, cellular transformation, migration and invasion of CRC cells, as well as the promotion on apoptosis. Knockdown of KITLG by its specific siRNA confirmed a critical role of KITLG down‐regulation for the tumour‐suppressive effects of miR‐34c in CRC cells. In conclusion, our results demonstrated that miR‐34c might interfere with KITLG‐related CRC and could be a novel molecular target for CRC patients.