Downregulation Of miR-21 Expression Research Articles

LncRNA AFAP1-AS1 mediates breast cancer cell proliferation and migration through the miR-21/PTEN axis.

LncRNAs play various effects, mostly by sponging with miRNAs. Based on public databases integrating bioinformatics analyses and further validation in breast cancer(BC) tissue and cell lines, the effect of lncRNA AFAP1-AS1 on breast cancer cell proliferation and migration was verified. It might work via the miR-21/PTEN axis. The expression of AFAP1-AS1, which was significantly upregulated in BC tissues and cell lines, was correlated with old age and lymph node metastasis of patients with BC. Knockdown of AFAP1-AS1 inhibited the proliferation and migration of BC cells in vitro and in vivo. And downregulated miR-21 expression and upregulated PTEN expression additionally. Mechanistically, the knockdown of lncRNA AFAP1-AS1 upregulated PTEN expression and consequently attenuated miR-21-mediated enhanced BC cell proliferation and migration. LncRNA AFAP1-AS1 is a potential prognostic biomarker for BC patients.

Graphene Quantum Dot‐PEI‐Cyclodextrin Nanocarrier for Simultaneous miR21a Delivery and Cell Imaging in Cancer Therapy

AbstractOver‐expression of miR21 plays an important role in several cancers by promoting cancer cell proliferation, migration, invasion, and metastasis. Here, we attempted to prepare a beta cyclodextrin‐polyethyleneimine‐graphene quantum dot (βCD‐PEI‐GQD) nanocarrier for cellular delivery of miR21a. For this purpose, tosylated‐βCD and GQD were conjugated to branched PEI. The product was characterized by FTIR, 1H‐NMR, and fluorescence spectroscopy. The morphology, particle size distribution, and ζ‐potential of miR21a were examined by TEM and DLS following overnight incubation with βCD‐PEI‐GQD in aqueous media. The miR21 silencing was measured by stem‐loop RT‐PCR in HepG2 human hepatoma cell line. Cellular uptake and cell toxicity assays were determined by fluorescence microscopy and Trypan blue staining method, respectively. The formation of miR21a/CD‐PEI‐GQD Nanoplex with a decreased average size of 114 nm and a ζ‐potential (+36.1 mV) lower than CD‐PEI‐GQD nanocarrier by adding miR21a was confirmed at optimum C/P ratio =8.7. RT‐PCR revealed that miR21a/βCD‐PEI‐GQD Nanoplex significantly downregulated miR21 expression levels effectively. Overall, miR21a delivery using CD‐PEI‐GQD is presented as a novel trackable nanocarrier for cancer therapy.

Diosmin Mitigates Gentamicin-Induced Nephrotoxicity in Rats: Insights on miR-21 and -155 Expression, Nrf2/HO-1 and p38-MAPK/NF-κB Pathways.

Gentamicin (GNT) is the most frequently used aminoglycoside. However, its therapeutic efficacy is limited due to nephrotoxicity. Thus, the potential anticipatory effect of Diosmin (DIOS) against GNT-prompted kidney damage in rats together with the putative nephroprotective pathways were scrutinized. Four groups of rats were used: (1) control; (2) GNT only; (3) GNT plus DIOS; and (4) DIOS only. Nephrotoxicity was elucidated, and the microRNA-21 (miR-21) and microRNA-155 (miR-155) expression and Nrf2/HO-1 and p38-MAPK/NF-κB pathways were assessed. GNT provoked an upsurge in the relative kidney weight and serum level of urea, creatinine, and KIM-1. The MDA level was markedly boosted, with a decline in the level of TAC, SOD, HO-1, and Nrf2 expression in the renal tissue. Additionally, GNT exhibited a notable amplification in TNF-α, IL-1β, NF-κB p65, and p38-MAPK kidney levels. Moreover, caspase-3 and BAX expression were elevated, whereas the Bcl-2 level was reduced. Furthermore, GNT resulted in the down-regulation of miR-21 expression along with an up-regulation of the miR-155 expression. Histological examination revealed inflammation, degradation, and necrosis. GNT-provoked pathological abnormalities were reversed by DIOS treatment, which restored normal kidney architecture. Hence, regulating miR-21 and -155 expression and modulating Nrf2/HO-1 and p38-MAPK/NF-κB pathways could take a vital part in mediating the reno-protective effect of DIOS.

Pomegranate juice and punicalagin-mediated chemoprevention of hepatocellular carcinogenesis via regulating miR-21 and NF-κB-p65 in a rat model

BackgroundHepatocellular carcinoma (HCC) is the most common neoplasm among primary liver malignancies, accounting for 70%–85% of total liver cancer cases worldwide. It is also the second-leading cause of cancer-related death worldwide. Recent research has investigated naturally occurring products high in polyphenolic compounds in the regression and prevention of HCC. This study investigated the chemoprevention effects of pomegranate juice (PJ) and punicalagin (PCG) against diethylnitrosamine (DENA)-induced hepatocarcinogenesis in male albino rats.MethodsAnimals were randomized into six groups and treated for 11 weeks as follows: group 1 was a negative control group, group 2 was treated orally with 10 mL PJ per kilogram body weight (kg bw), group 3 was treated orally with 18.5 mg PCG/kg bw, and groups 4–6 were injected with an intraperitoneal dose of DENA (50 mg/kg bw) weekly beginning in the third week. Group 4 was a HCC control (DENA-treated group), group 5 was HCC + PJ, and group 6 was HCC + PCG.ResultsPJ antagonized DENA-induced elevations of ALAT, TNF-α, NF-κB-p65, GST, MDA, and NO and restored total protein, IL-10, SOD, and CAT levels. Moreover, PJ resulted in downregulation of miR-21, Bcl-2, and Bcl-XL and an upregulation of caspase-3 and Bax mRNA expressions. These chemoprevention effects of PJ also alleviated the hepatic preneoplastic lesions induced by DENA. Although PCG treatment induced some modulation in DENA-treated rats, it did not show potent chemoprevention activity and induced some side effects.ConclusionBoth of PJ and PCG downregulated miR-21 expression and triggered apoptosis. However, PJ was more effective than pure PCG in alleviating the hepatic antioxidant defense state and the inflammatory status. So, PJ was superior in prevention of DENA-induced hepatocellular carcinogenesis in rats than pure PCG.Graphical

Construction of a Stimuli-Responsive DNAzyme-Braked DNA Nanomachine for the Amplified Imaging of miRNAs in Living Cells and Mice

Construction of a Stimuli-Responsive DNAzyme-Braked DNA Nanomachine for the Amplified Imaging of miRNAs in Living Cells and Mice

Atorvastatin Restores PPARα Inhibition of Lipid Metabolism Disorders by Downregulating miR-21 Expression to Improve Mitochondrial Function and Alleviate Diabetic Nephropathy Progression.

Atorvastatin is a classical lipid-lowering drug. It has been reported to have renoprotective effects, such as reducing urinary protein excretion and extracellular matrix aggregation. The present study aimed to investigate the specific mechanism of action of Atorvastatin in type 1 diabetic mice (T1DM) in inhibiting renal tubular epithelial cell injury following treatment with high glucose and high fat. The anti-injury mechanism of Atorvastatin involved the inhibition of miR-21 expression and the upregulation of the transcription and expression of its downstream gene Peroxisome proliferator-activated receptors-α(PPARα). An increase in blood glucose and lipid levels was noted in the T1DM model, which was associated with renal fibrosis and inflammation. These changes were accompanied by increased miR-21 levels, downregulation of PPARα and Mfn1 expressions, and upregulation of Drp1 and IL6 expressions in renal tissues. These phenomena were reversed following the administration of Atorvastatin. miR-21 targeted PPARα by inhibiting its mRNA translation. Inhibition of miR-21 expression or Fenofibrate (PPARα agonist) administration prevented the decrease of PPARα in renal tubular epithelial cells under high glucose (HG) and high fat (Palmitic acid, PA) conditions, alleviating lipid metabolism disorders and reducing mitochondrial dynamics and inflammation. Consistent with the in vivo results, the in vitro findings also demonstrated that mRTECs administered with Atorvastatin in HG + PA increased PPARα expression and restored the normal expression of Mfn1 and Drp1, and effectively increasing the number of biologically active mitochondria and ATP content, reducing ROS production, and restoring mitochondrial membrane potential following Atorvastatin intervention. In addition, these effects were noted to the inhibition of FN expression and tubular cell inflammatory response; however, in the presence of miR-21mimics, the aforementioned effects of Atorvastatin were significantly diminished. Based on these observations, we conclude that Atorvastatin inhibits tubular epithelial cell injury in T1DM with concomitant induction of lipid metabolism disorders by a mechanism involving inhibition of miR-21 expression and consequent upregulation of PPARα expression. Moreover, Atorvastatin regulated lipid metabolism homeostasis and PPARα to restore mitochondrial function. The results emphasize the potential of Atorvastatin to exhibit lipid-regulating functions and non-lipid effects that balance mitochondrial dynamics.

MicroRNA-21 protects against sepsis-induced acute lung injury by targeting phosphatase and tensin homolog in mice

Introduction: Sepsis can cause acute lung injury (ALI), one of the leading causes of death in critically ill patients. The underlying mechanisms of sepsis-induced acute lung injury include excessive inflammation, oxidative stress, cell apoptosis, pulmonary edema, and lung tissue dysfunction. Recent studies have shown that miRNA-21 (miR-21) plays a vital role in sepsis-induced acute kidney injury. Relatively few studies have focused on the protective effects of ALI. This study aimed to determine the potential role of miR-21 in sepsis-induced ALI. Methods: We performed quantitative real-time polymerase chain reaction in a septic mouse model induced by cecal ligation and puncture (CLP) and found that miR-21 expression was upregulated. We then transfected the miR-21 precursor to upregulate miR-21 expression and miR-21 inhibitor to downregulate miR-21 expression. The sham group was exposed only to the cecum. ALI was induced by CLP, and the pre-miR-21+ALI and anti-miR-21+ALI groups were treated with miR-21 precursor or miR-21 inhibitor in the caudal vein before CLP. Pre-miR-21+ALI+PTEN inhibition (Pre-miR-21+ALI+PI) and anti-miR-21+ALI+PTEN inhibition (Anti-miR-21+ALI+PI) groups were treated with PTEN inhibition into the caudal vein after miR-21 transfection. Inflammatory cytokines, oxidative stress indicators, lung tissue cell apoptosis, oxygenation index (OI), lung wet/dry weight ratio, and lung pathological changes in the lung were observed in each group. Results: Compared with ALI mice, inflammatory response, oxidative stress indicators, lung tissue cell apoptosis, and the degree of lung injury were remarkably alleviated in Pre-miR-21+ALI mice and aggravated in Anti-miR-21+ALI mice. Western blot analysis showed that phosphatase and tensin homolog (PTEN) protein expression was decreased in CLP-treated mics. PTEN protein expression was decreased in the Pre-miR-21+ALI group but increased in the Anti-miR-21+ALI group. Moreover, the effect of miR-21 on anti-inflammatory, anti-oxidative stress, and anti-apoptosis enhanced after PTEN inhibition. Conclusion: This study revealed that miR-21 has a protective effect in sepsis-induced ALI by regulating PTEN in mice.

Quercetin attenuates lipopolysaccharide-mediated inflammatory injury in human nasal epithelial cells via regulating miR-21/DMBT1/NF-κB axis

Background Quercetin (Qu) belongs to a flavonoid polyphenolic compound present in fruits and vegetables which has been confirmed to exert anti-inflammatory properties. Our study aimed to explore the impacts of quercetin on lipopolysaccharide (LPS)-induced inflammatory injury and signal transduction of miR-21/DMBT1/NF-κB axis in human nasal epithelial cells (HNEpC). Methods HNEpCs were cultured and treated with 1 μg/mL of LPS and a gradient concentration (10, 100, and 200 μM) of quercetin for 24 h. Cell viability, apoptosis, and cytokines were detected to assess the inflammatory injury in LPS-exposed HNEpCs. The expressions of miR-21, DMBT1, and NF-κB mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The levels of DMBT1 and NF-κB protein were measured by western blotting. Results LPS treatment reduced cell viability, promoted cell apoptosis and inflammatory response, down-regulated miR-21 expression and up-regulated DMBT1, and NF-κB in HNEpC cells. Quercetin exerted the opposite effects to attenuate LPS-induced inflammatory injury in HNEpC cells at a concentration-dependent way. Additionally, miR-21 directly targeted DMBT1 to reduce its expression and further inducing cell viability via inhibiting cell apoptosis and inflammatory response. MiR-21 inhibition or DMBT1 over-expression weakened the protective effects of quercetin against LPS-induced inflammatory injury in HNEpC cells. Conclusions Quercetin could protect HNEpC cells against LPS-induced inflammatory injury via inducing miR-21/DMBT1/NF-κB axis. Therefore, quercetin could be utilized as a potential compound to treat for allergic rhinitis.

The effects of gastric cancer interstitial fluid on tumors based on traditional Chinese medicine 'phlegm' theory and the investigation on the mechanism through microRNA-21 regulation.

This study aimed to investigate the effects of gastric cancer interstitial fluid (GCIF) on tumors and explore the possible mechanism of Xiaotan Sanjie decoction (XTSJ) on treatment of gastric cancer from the view of regulating microRNA-21 (miR-21) expression. The GCIF was extracted and identified by measuring the levels of interleukin-8 (IL-8), intercellular adhesion molecule 1 (ICAM-1) and miR-21. The effects of GCIF on the proliferation of SGC-7901 cells and tumor growing were assessed by cell counting kit-8 (CCK-8) assay and subcutaneously transplanted tumor-bearing nude mice model, respectively. Additionally, inhibition effect of XTSJ decoction on proliferation of SGC-7901 cells intervened by GCIF were assessed in vitro and anti-cancer effect of it was further assessed using orthotopic transplanted tumor-bearing nude mice model. The concentration of SGC-7901 gastric cancer cells were dependent on the concentration of the added GCIF. After 72 hours of continuous culture, the interstitial fluid had an obvious proliferative effect on the SGC-7901 tumor cells, which was the most significant in the high concentration group. XTSJ decoction could inhibit the growth-promoting effect (P < 0.01) of GCIF on gastric cancer cells. Intervention of the GCIF might promote the growth (P < 0.05) of the subcutaneously transplanted tumors in nude mice and decrease the net weight of the tumor-bearing nude mice (P < 0.05) after tumor removal. The GCIF was able to up-regulate the expression (P < 0.001) of miR-21 in the subcutaneously transplanted tumors. XTSJ decoction could downregulate the expression (P < 0.05) of miR-21 in SGC-7901 orthotopically transplanted tumors. XTSJ decoction can inhibit the multiplicative effect of GCIF on gastric cancer cells, growth of gastric tumor and promotion effect of GCIF on tumors, probably due to the down-regulating miR-21 expression in tumor tissues.

Curcumin Inhibits Hepatocellular Carcinoma via Regulating miR-21/TIMP3 Axis.

Background/Aim Curcumin exhibits anticancer effects against various types of cancer including hepatocellular carcinoma (HCC). miR-21 has been reported to be involved in the malignant biological properties of HCC. However, whether miR-21 plays a role in curcumin-mediated treatment of HCC is unknown. The purpose of this study was to identify the potential functions and mechanisms of miR-21 in curcumin-mediated treatment of HCC. Methods The anticancer effects of curcumin were assessed in vivo and in vitro. The underlying mechanism of miR-21 in curcumin-mediated treatment of HCC was assessed by quantitative real-time PCR (RT-qPCR), western blot, and Dual-Luciferase Reporter assays. Results The present study revealed that curcumin suppressed HCC growth in vivo and inhibited HCC cell proliferation and induced cell apoptosis in a dose-dependent manner in vitro. Meanwhile, the curcumin treatment can downregulate miR-21 expression, upregulate TIMP3 expression, and inhibit the TGF-β1/smad3 signaling pathway. miR-21 inhibition enhanced the effect of curcumin on cell proliferation inhibition, apoptosis, and TGF-β1/smad3 signaling pathway inhibition in HepG2 and HCCLM3 cells. It demonstrated that TIMP3 was a direct target gene of miR-21. Interestingly, the effect of miR-21 inhibition on cell proliferation, apoptosis, and TGF-β1/smad3 signaling pathway in HepG2 and HCCLM3 cells exposed to curcumin was attenuated by TIMP3 silencing. Conclusion Taken together, the present study suggests that miR-21 is involved in the anticancer activities of curcumin through targeting TIMP3, and the mechanism possibly refers to the inhibition of TGF-β1/smad3 signaling pathway.

Therapeutic potential of miR-21 regulation by human peripheral blood derived-small extracellular vesicles in myocardial infarction.

Small extracellular vesicles (sEVs) as natural membranous vesicles are on the frontiers of nanomedical research, due to their ability to deliver therapeutic molecules such as microRNAs (miRNAs). The miRNA-21 (miR-21) is thought to be involved in the initiation and development of myocardial infarction (MI). Here, we examined whether miR-21 regulation using human peripheral blood-derived sEVs (PB-sEVs) could serve as a potential therapeutic strategy for MI. First, we examined miR-21 levels in hypoxic conditions and validated the ability of PB-sEVs to serve as a potential delivery system for miRNAs. Further, bioinformatics analysis and luciferase assay were performed to identify target genes of miR-21 mechanistically. Among numerous target pathways, we focused on nitrogen metabolism, which remains relatively unexplored compared with other possible miR-21-mediated pathways; hence, we aimed to determine novel target genes of miR-21 related to nitrogen metabolism. In hypoxic conditions, the expression of miR-21 was significantly up-regulated and correlated with nitric oxide synthase 3 (NOS3) levels, which in turn influences cardiac function. The down-regulation of miR-21 expression by PB-sEVs loaded with anti-miR-21 significantly improved survival rates, consistent with the augmentation of cardiac function. However, the up-regulation of miR-21 expression by PB-sEVs loaded with miR-21 reversed these effects. Mechanistically, miR-21 targeted and down-regulated the mRNA and protein expression of striatin (STRN), which could regulate NOS3 expression. In conclusion, we identified a novel therapeutic strategy to improve cardiac function by regulating the expression of miR-21 with PB-sEVs as an miR-21 or anti-miR-21 delivery vehicle and confirmed the miR-21-associated nitrogen metabolic disorders in MI.

Engineered exosomes for targeted co-delivery of miR-21 inhibitor and chemotherapeutics to reverse drug resistance in colon cancer

Background5-Fluorouracil (5-FU) has been commonly prescribed for patients with colorectal cancer (CRC), but resistance to 5-FU is one of the main reasons for failure in CRC. Recently, microRNAs (miRNAs) have been established as a means of reversing the dilemma by regulating signaling pathways involved in initiation and progression of CRC. However, how to safely and effectively deliver miRNA to target cells becomes a main challenge.ResultsIn this study, Engineered exosomes were exploited to simultaneously deliver an anticancer drug 5-FU and miR-21 inhibitor oligonucleotide (miR-21i) to Her2 expressing cancer cells. Purified engineered exosomes from the donor cells loaded with 5-FU and miR-21i via electroporation to introduce into 5-FU-resistant colorectal cancer cell line HCT-1165FR. Furthermore, systematic administration of 5-FU and miR-21i loaded exosomes in tumor bearing mice indicated a significantly anti-tumor effect. The results showed that the engineered exosome-based 5-FU and miR-21i co-delivery system could efficiently facilitate cellular uptake and significantly down-regulate miR-21 expression in 5-FU resistant HCT-1165FR cell lines. Consequently, the down-regulation of miR-21 induced cell cycle arrest, reduced tumor proliferation, increased apoptosis and rescued PTEN and hMSH2 expressions, regulatory targets of miR-21. Of particular importance was the significant reduction in tumor growth in a mouse model of colon cancer with systematic administration of the targeting miR-21i. More excitedly, the combinational delivery of miR-21i and 5-FU with the engineered exosomes effectively reverse drug resistance and significantly enhanced the cytotoxicity in 5-FU-resistant colon cancer cells, compared with the single treatment with either miR-21i or 5-FU.ConclusionThe strategy for co-delivering the functional small RNA and anticancer drug by exosomes foreshadows a potential approach to reverse the drug resistance in CRC and thus to enhance the efficacy of the cancer treatment.

The Long Noncoding RNA, Growth Arrest-Specific 5, Suppresses Gastric Cancer by Downregulating miR-21 Expression

Background: Gastric cancer has become the second major cause of cancer death. The aim of the present study was to explore the relationship between miR-21 and the long noncoding RNA growth arrest-specific 5 (GAS5) in gastric cancer and the effect on gastric cancer cells. Methods: The expression of miR-21 and GAS5 mRNA was analyzed by quantitative real-time-PCR. Overexpression of GAS5 was used to investigate the biological functions of GAS5 in cells. The cell proliferation was detected by cell counting kit-8 assay and the cell migration and invasion were detected by Transwell. Cell apoptosis was evaluated by Annexin V-FITC/PI staining and apoptosis-related proteins were detected by western blot. The mechanism of GAS5 in vivo was evaluated by the tumorigenesis of nude mice, and dual luciferase reporter was used to determine if miR-21 is a GAS5 target. The inhibition of miR-21 and the simultaneous overexpression of GAS5 and miR-21 were further performed, and the above indicators were detected again. Results: GAS5 was low expression and miR-21 was high expression in gastric cancer tissues and cells. GAS5 overexpression reduced the proliferation, migration, and invasion of gastric cancer cells and increased the apoptosis of gastric cancer cells. The growth rate of GAS5 group slowed down and the volume of tumor decreased. miR-21 is a GAS5 target and GAS5 inhibits the proliferation of gastric cancer cells by targeting miR-21. Conclusion: Our research shown that overexpression of GAS5 can significantly inhibit the proliferation, migration, invasion and tumor formation of gastric cancer cells, and promote the apoptosis of gastric cancer cells, which may be related to the targeting inhibition of miR-21 expression by GAS5.

Potential Therapeutic Effects of Exosomes Packed With a miR-21-Sponge Construct in a Rat Model of Glioblastoma.

Glioblastoma multiforme (GBM) is a grade 4 and the most aggressive form of glioma, with a poor response to current treatments. The expression of microRNAs (miRNAs) is widely dysregulated in various cancers, including GBM. One of the overexpressed miRNAs in GBM is miR-21 which promotes proliferation, invasion and metastatic behaviors of tumor cells. With a size of 30–100 nm, the extracellular vesicles “exosomes” have emerged as a novel and powerful drug delivering systems. Recently, exosomal transfer of miRNAs or anti-miRNAs to tumor cells has introduced a new approach for therapeutic application of miRNAs to combat cancer. Here, we have tried to down-regulate miR-21 expression in glioma cell lines, U87-MG, and C6, by using engineered exosomes, packed with a miR-21-sponge construct. Our data revealed that the engineered exosomes have the potential to suppress miR-21 and consequently to upregulate miR-21 target genes, PDCD4 and RECK. Interestingly, in cells treated with miR-21-sponge exosomes we observed a decline in proliferation and also an elevation in apoptotic rates. Finally, in a rat model of glioblastoma, administrating exosomes loaded with a miR-21-sponge construct leads to a significant reduction in the volume of the tumors. In brief, our findings suggest a new therapeutic strategy to use engineered exosomes to deliver a miR-21-sponge construct to GBM cells, in order to block its malignant behavior.

RETRACTED: Skullcapflavone I suppresses proliferation of human lung cancer cells via down-regulating microRNA-21

Lung cancer is the most leading cause of cancer-related deaths worldwide. Skullcapflavone I is a flavone compound extracted from Scutellaria baicalensis Georgi (Wogon). The present study investigated the effects of skullcapflavone I on human lung cancer cell proliferation, as well as underlying possible mechanism. Cell proliferation was detected using Trypan blue assay. Cell viability was measured using cell counting kit 8 (CCK-8) assay. Quantitative reverse transcription PCR (qRT-PCR) was performed to assess microRNA-21 (miR-21) expression. Cell transfection was conducted to enhance the levels of miR-21 and protein phosphatase 2A (PP2A). Western blotting was used to evaluate the expressions of proliferation cell nuclear antigen (PCNA), Cyclin D1, PP2A, phosphatidylinositol 3-kinase (PI3K), protein kinase 3 (AKT), mechanistic target of rapamycin (mTOR) and p70S6K. Skullcapflavone I significantly suppressed the viability and proliferation of A549 and H1975 cells. The expressions of miR-21 in A549 and H1975 cells were drastically decreased after skullcapflavone I treatment. Overexpression of miR-21 remarkably reversed the skullcapflavone I-induced A549 cell viability inhibition. Moreover, skullcapflavone I enhanced the expression of PP2A in A549 cells. Skullcapflavone I inactivated PI3K/AKT/mTOR signaling pathway in A549 cells via up-regulating PP2A. Besides, skullcapflavone I treatment had no significant influence on human normal bronchial epithelial 16HBE cell viability, proliferation and apoptosis. Skullcapflavone I exerted anti-cancer effect on lung cancer cells by down-regulating miR-21 expression, up-regulating PP2A expression and then inactivating PI3K/AKT/mTOR signaling pathway.

Budesonide up-regulates vitamin D receptor expression in human bronchial fibroblasts and enhances the inhibitory effect of calcitriol on airway remodeling

Introduction and objectivesTransforming growth factor β1 (TGFβ1) and dysregulated microRNA-21 (miR-21) expression is associated with TGFβ/Smad signaling pathway activation and fibrosis. While calcitriol has been shown to improve airway remodeling in asthmatic mice, its mechanism remains unknown. In this study, the effect of calcitriol on the TGFβ/Smad signaling pathway and miR-21 expression in human bronchial fibroblasts was investigated to explore the mechanism of action of calcitriol and the inhaled glucocorticoid, budesonide, in airway remodeling. Materials and methodsHuman bronchial fibroblasts were pretreated with budesonide, calcitriol, or budesonide plus calcitriol, and stimulated with TGFβ1 for 48h. Quantitative real-time PCR was used to determine the expression of miR-21. Western blot was used to determine airway remodeling-related proteins, TGFβ/Smad signaling pathway-related proteins, glucocorticoid receptor, and vitamin D receptor (VDR) expression. ResultsBoth budesonide and calcitriol down-regulated miR-21 expression in human bronchial fibroblasts, up-regulated Smad7 expression, and inhibited the expression of airway remodeling-related proteins. Both budesonide and calcitriol up-regulated the low expression of VDR induced by TGFβ1 in human bronchial fibroblasts. The expression of VDR in the combined treatment group (budesonide plus calcitriol) was significantly higher than that in the calcitriol treatment group. The expression of collagen type I in the combined treatment group was significantly lower than that in the calcitriol treatment group. ConclusionsCalcitriol can up-regulate the expression of VDR in human bronchial fibroblasts and exert an anti-airway remodeling effect. Budesonide can up-regulate the expression of VDR in human bronchial fibroblasts and enhance the inhibitory effect of calcitriol on airway remodeling.

Propofol inhibits proliferation and epithelial-mesenchymal transition of MCF-7 cells by suppressing miR-21 expression

Breast cancer is a common malignant tumor with a high incidence of recurrence and metastasis. It has been reported that propofol has certain anti-breast cancer effects, but the intrinsic molecular mechanism remains unclear. This study investigated the effect of propofol on breast cancer MCF-7 cells and its possible regulatory mechanisms. MCF-7 cells were treated by propofol, and then the effects of propofol on cell growth and epithelial-mesenchymal transition (EMT) were studied. We subsequently testified whether miR-21 was a downstream effector of propofol. As a result, propofol repressed the proliferation and migration of MCF-7 cells, but significantly induced apoptosis. Meanwhile, miR-21 expression and EMT were inhibited by propofol stimulation. The effects of propofol on MCF-7 cells proliferation, apoptosis and EMT were all attenuated when miR-21 was overexpressed. Besides this, the activation of PI3K/AKT and Wnt3a/β-catenin pathways was reduced by propofol stimulation in a miR-21-depedent manner. In conclusion, propofol can inhibit the proliferation and EMT of MCF-7 cells by down-regulating miR-21 expression. Moreover, miR-21 can further regulate PI3K/AKT and Wnt/β-catenin pathways.

Lidocaine alleviates cytotoxicity-resistance in lung cancer A549/DDP cells via down-regulation of miR-21.

Lidocaine (Lido) is a commonly used local anesthetic, which has been reported in various types of cells. However, the effects of Lido on lung cancer cells remain not understood. The study aimed to investigate the underlying mechanisms of Lido in the cisplatin resistance of A549/DDP cells. Different concentrations of cisplatin (0-320µM) were used to stimulate A549 and A549/DDP cells, and cell viability and apoptosis were examined. To investigate the effect of Lido on A549/DDP cells, the optimum concentration of Lido was selected to treat A549/DDP cells, and cell viability, apoptosis, migration and invasion were then detected. The relative expression of miR-21 in A549/DDP cells or in Lido-treated A549/DDP cells was analyzed by RT-qPCR. MiR-21 mimic, inhibitor and its control were transfected into A549/DDP cells to explore the regulatory effect of miR-21 on the cisplatin resistance in A549 or A549/DDP cells. The effects of miR-21 on PTEN/PI3K/AKT and PDCD4/JNK pathways were detected by western blot. The cisplatin resistance of A549/DDP cells was higher than that of A549 cells. Lido significantly suppressed cell viability, induced apoptosis, and inhibited cell migration and invasion in A549/DDP cells. Additionally, miR-21 expression in A549/DDP was higher than that in A549 cells, and Lido significantly down-regulated miR-21 expression in A549/DDP cells. MmiR-21 inhibition exhibited the same effects as Lido on the cisplatin resistance of A549/DDP cells. Further, miR-21 suppression regulated PTEN/PI3K/AKT and PDCD4/JNK pathways in A549/DDP cells. These findings indicated that Lido alleviated the cytotoxicity resistance of A549/DDP cells via down-regulation of miR-21.

Compound Astragalus and Salvia miltiorrhiza extract inhibits hepatocellular carcinoma progression via miR-145/miR-21 mediated Smad3 phosphorylation

Ethnopharmacological relevanceCompound Astragalus and Salvia miltiorrhiza extract (CASE), containing astragalosides, astragalus polysaccharide extracted from Astragalus membranaceus (Fisch.) Bge. and salvianolic acids from Salvia miltiorhiza Bge., has been found to inhibit hepatocarcinogenesis via mediating transforming growth factor-β (TGF-β)/Smad signaling, especially Smad3 phosphorylation. The crucial interaction between microRNA-145/microRNA-21 (miR-145/miR-21) and Smad3 phosphorylation is implicated in the pathogenesis and progression of hepatocellular carcinoma (HCC). However, effects of CASE on HCC progression involved in the expression of miR-145/miR-21 and their interaction with Smad3 phosphorylation downstream of TGF-β/MAPK/Smad pathway remain unclear. This study addressed above questions using in vitro (HepG2 cells) and in vivo (Xenografts of nude mice) models of HCC. Materials and methodsIn vivo [Diethylnitrosamine (DEN)-induced HCC in rats] and in vitro [TGF-β1-stimulated HepG2 cells] models of HCC were established and co-administrated using graded doses/concentrations CASE (60, 120, 240 mg/kg used in rats; 20, 40, 80 µg/ml used in HepG2 cells), miR-145 and miR-21 were measured. HepG2 cells were transfected with miR-145 antagomir, miR-21 agomir and Smad3C/L plasmids (Smad3 EPSM, Smad3 3S-A and Smad3 WT related to up-regulated expression of pSmad3C, pSmad3L and pSmad3C/3L respectively) and then treated by CASE (80 µg/ml). Similarly, HepG2 cell xenografted nude mice were administered with miR-145 antagomir, miR-21 agomir and CASE (310 mg/kg); Smad3 WT, Smad3 EPSM and Smad3 3S-A plasmids stably transfected HepG2 cell lines were constructed respectively and their xenografted nude mice were established, and then treated by CASE (310 mg/kg). Cell proliferation, migration, apoptosis, tumor growth and histopathologic characteristics of xenografts were assessed; also, domain-specific Smad3 phosphorylation isoforms (pSmad3C/pSmad3L), activated MAPKs (pERK1/2, pJNK1/2, pp38) and miR-145, miR-21 were measured. ResultsCASE up-regulated miR-145 while down-regulated miR-21 expression in both rats with DEN-induced HCC and TGF-β1-stimulated HepG2 cells; CASE inhibited cell migration, proliferation and tumor growth while facilitated cell apoptosis in TGF-β1-stimulated HepG2 cells and xenografts of nude mice with miR-145 antagomir/miR-21 agomir treatment via increasing miR-145 and facilitating miR-145 modulated pSmad3L→pSmad3C signaling switch while decreasing miR-21 and inhibiting miR-21 modulated MAPK-dependent Smad3L phosphorylation. Also, up-regulated pSmad3C enhanced inhibited effect of CASE on tumor growth and facilitated effect of CASE on cell apoptosis involved in increased miR-145 while decreased miR-21 expression, however, inverse phenomena were observed when up-regulated pSmad3L. ConclusionOur results suggest that CASE inhibits HCC progression via mediating the interaction of miR-145/miR-21 and Smad3 phosphorylation, especially miR-145/miR-21 mediated Smad3 phosphorylation, which maybe provides an important theoretical foundation for CASE's anti-HCC therapy used for patients in a near future.

甘草次酸对银屑病患者角质形成细胞增殖、凋亡及miR-21表达的影响

Objective To preliminarily evaluate the effect of glycyrrhetinic acid on the proliferation and apoptosis of keratinocytes in patients with psoriasis, and to explore its possible mechanisms. Methods Keratinocytes were isolated from patients with psoriasis, and subjected to a primary culture in vitro. After 2-3 passages, the keratinocytes were divided into several groups to be treated with glycyrrhetinic acid at final concentrations of 0 (control group) , 1, 2, 4, 8 and 10 mg/L (glycyrrhetinic acid groups) , respectively. After 24-72 hours of treatment, MTS assay was performed to evaluate the effect of glycyrrhetinic acid on the proliferation of keratinocytes, and flow cytometry was conducted to detect the apoptosis of keratinocytes after 24-hour treatment with glycyrrhetinic acid at different concentrations. Real-time fluorescence-based PCR was performed to determine the expression of miR-21 in keratinocytes. Results After 24-72 hours of treatment with 1-10 mg/L glycyrrhetinic acid, the proliferation activity of keratinocytes significantly decreased along with the increase in the treatment duration and concentrations of glycyrrhizinic acid. After 24-hour treatment with 1, 2, 4, 8, 10 mg/L glycyrrhetinic acid, the apoptosis rates of keratinocytes increased to (9.64 ± 0.86) %, (25.24 ± 2.93) %, (27.68 ± 3.70) %, (35.55 ± 4.23) % and (38.89 ± 2.31) % respectively. As LSD-t test showed, the apoptosis rates of keratinocytes were significantly higher in all the glycyrrhetinic acid groups than in the control group (10.09% ± 0.69%, all P < 0.01) , except the 1 mg/L glycyrrhetinic acid group. After 24-hour treatment with 1, 2 and 4 mg/L glycyrrhetinic acid, the miR-21 expression (2-ΔΔCt) significantly decreased (0.24 ± 0.04, 0.22 ± 0.07, 0.17 ± 0.05, respectively) compared with the control group (0.92 ± 0.12, F= 213.10, P < 0.05) . After 18-, 24-and 48-hour treatment with 2 mg/L glycyrrhetinic acid, the miR-21 expression significantly decreased (0.55 ± 0.02, 0.22 ± 0.06 and 0.15 ± 0.06 respectively) compared with the control group (0.98 ± 0.02, F= 238.10, P < 0.05) . Conclusion Glycyrrhetinic acid can inhibit the proliferation of keratinocytes from psoriatic patients, but promote the apoptosis, likely by down-regulation of miR-21 expression. Key words: Psoriasis; Glycyrrhetinic acid; Keratinocytes; Cell proliferation; Apoptosis; MicroRNAs; miR-21