Double Luciferase Reporter Gene Assay Research Articles

CircRNA ACAP2 induces myocardial apoptosis after myocardial infarction by sponging miR-29.

The aim of this study was to investigate the effect of circular RNA circ ACAP2 on apoptotic phenotype of rat cardiomyocytes and its molecular mechanism. Left anterior descending ligation was used to establish a rat myocardial infarction (MI) model, and real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of circ ACAP2 in apoptotic rat cardiomyocytes. The stability of circ ACAP2 was tested by actinomycin D and RNase R. H9C2 cells were infected by recombinant circ ACAP2 adenovirus (rAd-circ ACAP2), and the expression of apoptotic related genes Bax and BCL-2 in H9C2 was detected. Double luciferase reporter gene experiment, RNA antisense purification experiment and RNA Pull-Down experiments verified the binding effect of circ ACAP2 and miR-29. RT-qPCR results showed that the expression of circ ACAP2 was increased in cardiomyocytes of MI rats. Actinomycin D and RNase R experiment confirmed that circ ACAP2 had better stability and resistance to RNase R degradation than its host gene ACAP2 mRNA. Overexpression of circ ACAP2 promotes apoptosis. The double luciferase reporter gene assay, RNA antisense purification assay and RNA Pulldown assay consistently confirmed the specific binding effect between circ ACAP2 and miR-29, and circ ACAP2 promoted the apoptotic phenotype in rats. The expression of circ ACAP2 increased in cardiomyocytes after MI and promoted apoptosis by binding to miR-29.

MicroRNA-23a knockdown attenuates angiotensin Ⅱ induced hypertrophy in rat H9c2 cells via activating PTEN and AMPK pathway

Objective: To investigate if microRNA (miR) -23a knockdown could attenuate angiotensin Ⅱ(AngⅡ) induced cardiac hypertrophy by activating phosphatase and tensin homolog deleted on chromosome ten(PTEN) and AMP-activated protein kinase(AMPK) pathway. Methods: Rat H9c2 cells were cultured in DMEM high glucose medium and put in 5% CO(2) incubator at 37 ℃(normal group). After 48 hours of culture, H9c2 cells were stimulated with 10 nmol/L AngⅡ to establish cell hypertrophy model (AngⅡgroup). The H9c2 cells were inoculated in a 6-well cell culture plate and cultured in an incubator at 37 ℃. When the confluence degree of cell growth was about 70%, the cells were transfected with different reagents, and 24 hours after transfection, 10 nmol/L AngⅡ was used to interfere with the cells. The H9c2 cells were divided into different groups according to the reagents, namely AngⅡ+anti-miR group(transfected with miR-23a inhibitor), Ang Ⅱ+NC group(transfected with miR-23a inhibitor negative control), Ang Ⅱ+anti-miR+si-PTEN group(cotransfected with miR-23a inhibitor and PTEN small interference RNA(siRNA)), and AngⅡ+anti-miR+si-NC group(cotransfected with miR-23a inhibitor and PTEN siRNA negative control). The surface area of single cell was measured by Image J software.The mRNA expression levels of α-actin 1 (ACTA1) and β-myosin heavy chain (β-MHC) and miR-23a were detected by quantitative real-time PCR(qRT-PCR). The expression levels of PTEN and AMPK signal pathway related proteins were detected by Western blot. In order to verify whether miR-23a targets PTEN gene, double luciferase reporter gene experiment was performed. The luciferase reporter gene vector recombinant plasmids of wild type pGL-WT-PTEN and mutant pGL-MUT-PTEN were constructed and prepared after normal sequencing. H9c2 cells was inoculated into 24-well cell culture plate and cultured overnight in 37 ℃ incubator. The cells were co-transfected with miR-23a mimic or miR-23a mimic negative control and wild type or mutant reporter gene recombinant plasmid. Forty-eight hours after transfection, firefly luciferase activity and sea kidney luciferase activity were measured, and the ratio of them was recorded as relative luciferase activity. Results: Compared with the normal group, the cell surface area, the mRNA expression levels of ACTA1, β-MHC and miR-23a were significantly higher, while the protein expression levels of PTEN and p-AMPK were significantly lower in the Ang Ⅱ group(all P<0.05). The results of double luciferase reporter gene assay showed that the relative luciferase activity of cells co-transfected with miR-23a mimic and wild-type reporter gene recombinant plasmid was lower than that of miR-23a mimic negative control (P<0.05), and PTEN served as the target gene of miR-23a. In AngⅡ+anti-miR group the mRNA expression levels of miR-23a, ACTA1 and β-MHC were lower, and the cell surface area was smaller, while the protein expression levels of PTEN and p-AMPK were higher than that in AngⅡ group and AngⅡ+NC group(all P<0.05). Compared with AngⅡ+anti-miR group, the cell surface area was bigger, the expression of ACTA1 and β-MHC mRNA was up-regulated, and the protein expression levels of PTEN and p-AMPK were down-regulated in Ang Ⅱ+anti-miR+si-PTEN group(all P<0.05). Conclusion: Inhibition of miR-23a can attenuate Ang Ⅱ-induced hypertrophy in H9c2 cells through targeting PTEN and activating AMPK signaling pathway.

Exosomal miR-182 regulates the effect of RECK on gallbladder cancer.

BACKGROUNDAs the most common biliary malignancy, gallbladder cancer (GC) is an elderly-biased disease. Although extensive studies have elucidated the molecular mechanism of microRNA 182 (miR-182) and reversion-inducing-cysteine-rich protein with kazal motifs (RECK) in various cancers, the specific role of exosomal miR-182 and RECK in GC remains poorly understood.AIMTo explore the relationship between exosomal miR-182/RECK and metastasis of GC.METHODSPaired GC and adjacent normal tissues were collected from 78 patients. Quantitative polymerase chain reaction was employed to detect miR-182 and exosomal miR-182 expression, and Western blotting was conducted to determine RECK expression. In addition, the effects of exosomal miR-182/RECK on the biological function of human GC cells were observed. Moreover, the double luciferase reporter gene assay was applied to validate the targeting relationship between miR-182 and RECK.RESULTSCompared with normal gallbladder epithelial cells, miR-182 was highly expressed in GC cells, while RECK had low expression. Exosomal miR-182 could be absorbed and transferred by cells. Exosomal miR-182 inhibited RECK expression and promoted the migration and invasion of GC cells.CONCLUSIONExosomal miR-182 can significantly promote the migration and invasion of GC cells by inhibiting RECK; thus miR-182 can be used as a therapeutic target for GC.

Study on adsorption of microRNA-124 by long chain non-coding RNA MALAT1 regulates osteogenic differentiation of mesenchymal stem cells

To investigate the regulatory effect of long chain non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) adsorbing microRNA-124 (miR-124) on osteogenic differentiation of mesenchymal stem cells (MSCs). C3H10T1/2 cells derived from mouse embryos were cultured in vitro, then randomly divided into control group (group A), lncRNA MALAT1 no-load plasmid group (group B), lncRNA MALAT1 overexpression plasmid group (group C), lncRNA MALAT1 small interfering RNA (siRNA) group (group D), and lncRNA MALAT1 siRNA negative control group (group E). The cells were transfected into plasmids and siRNA, then induced to differentiate into osteoblasts. Alkaline phosphatase (ALP) and alizarin red staining were used to detect the osteogenic differentiation of cells in each group, real-time fluorescence quantitative (qRT-PCR) analysis was used to detect the expressions of lncRNA MALAT, miR-124, and osteogenesis-related genes such as Runt-related transcription factor 2 (Runx2), osteopontin (OPN), and osteocalcin (OCN) in each group. Double luciferase reporter gene was used to detect the targeting regulation of lncRNA MALAT1 to miR-124. The relative contents of ALP positive cells, mineralized nodule, and the relative mRNA expressions of lncRNA MALAT1, Runx2, OPN, and OCN in group C were significantly higher than those in other groups ( P<0.05), while in group D significantly lower than in other groups ( P<0.05); the relative expression of miR-124 in group C was significantly lower than that in other groups( P<0.05), while in group D significantly higher than in other groups ( P<0.05). There was no significant difference in these indexes between groups A, B, and E ( P>0.05). The results of double luciferase reporter gene assay showed that lncRNA MALAT1 targeting down-regulated the expression of miR-124. LncRNA MALAT1 can targeting down-regulate the expression of miR-124 and promote the osteogenic differentiation of MSCs.

Effect of miR-513a-3p targeting MDM2 on proliferation, migration and invasion of gastric cancer cells

Objective: To investigate the effects of miR-513a-3p on proliferation, migration and invasion of gastric cancer cells and its mechanism. Methods: The miR-NC (miR-negative control mimics), miR-513a-3p (miR-513a-3p mimics), anti-miR-NC, anti-miR-513a-3p, si-NC, si-MDM2 (murine double minute 2), miR-513a-3p+ pcDNA3.1 (co-transfected with miR-513a-3p and pcDNA3.1), miR-513a-3p+ pcDNA3.1-MDM2 (co-transfected with miR-513a-3p and pcDNA3.1-MDM2) were transfected into BGC-823 cells, respectively. The expression of miR-513a-3p was detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), and the protein expressions of cyclin D1, MMP-2, p21, E-cadherin, MDM2 were detected by western blot. The viability of BGC-823 cells of each group was detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The migration and invasion of each group were detected by Transwell, the targeting relationship between miR-513a-3p and MDM2 was detected by double luciferase reporter gene assay. Results: The expression of miR-513a-3p in gastric epithelial cells GES-1 was 0.76±0.08, significantly higher than 0.21±0.02 in gastric cancer cells BGC-823 and 0.34±0.03 in MGC-803, respectively (P<0.05). The cell viabilities of the miR-NC group at 24 h, 48 h and 72 h were 0.57±0.05, 1.03±0.10, 1.43±0.14, respectively, while those of the miR-513a-3p group were 0.36±0.03, 0.48±0.05, and 0.63±0.06, respectively. The migration and invasion numbers of miR-NC group were 130±11.80 and 117±10.60, respectively, those of miR-513a-3p group were 58±5.64 and 50±5.13, respectively, and the differences were statistically significant (P<0.05). The cell viabilities of the si-NC group at 24 h, 48 h and 72 h were 0.53±0.05, 0.95±0.10, 1.36±0.14, respectively. Those of the si-MDM2 group were 0.39±0.04, 0.57±0.06, and 0.80±0.08, respectively. The cell migration and invasion of the si-NC group were 141±12.02 and 109±10.60, respectively, while those of the MDM2 group were 66±6.67 and 61±6.18, respectively, and the differences were statistically significant (P<0.05). The cell viabilities of the miR-513a-3p+ pcDNA3.1 group at 24 h, 48 h and 72 h were 0.34±0.03, 0.46±0.05, and 0.61±0.06, respectively. Those of miR-513a-3p+ pcDNA3.1-MDM2 group were 0.48±0.05, 0.82±0.08, 1.17±0.12, respectively. The migration and invasion of miR-513a-3p+ pcDNA3.1 group were 56±5.71 and 51±5.16, respectively, while those of miR-513a-3p+ pcDNA3.1-MDM2 group were 113±10.28 and 104±10.02, respectively, and the differences were statistically significant (P<0.05). Conclusion: miR-513a-3p may inhibit the proliferation, migration and invasion of gastric cancer cells through targeting regulation of MDM2, which will provide new targets for the prevention and treatment of gastric cancer.

Diterpenoids as PPARγ agonists from Siegesbeckia pubescens and their anti-inflammatory effects in vitro

This study aims to investigate the PPARγ agonists isolated from the aqueous extract of Siegesbeckia pubescens( SPA) and their anti-inflammatory activities in vitro. The 293 T cells transfected transiently with PPARγ recombinant plasmid were used as a screening model to guide the isolation of PPARγ activitating components,and then PPARγ activities were measured by double luciferase reporter gene assay. The chemical structures were identified by chromatography or spectroscopic techniques. Furthermore,a UC inflammatory model in vitro was established on HT-29 cells by stimulating with TNF-α． The mRNA levels and secretion of proinflammatory cytokines on HT-29 cells,such as IL-1β,TNF-α,IL-8,were detected by RT-PCR and ELISA. The results showed that five diterpenoids were obtained from the fraction D_(50) with the strongest PPARγ activity among others in SPA,and determined as kirenol( 1),darutigenol( 2),enantiomeric-2-ketone-15,16,19-three hydroxypinomane-8( 14)-ene-19-O-β-D-glucoside( 3),darutoside( 4),enantiomeric-2-β,15,16,19-four hydroxypinomane-8( 14)-ene-19-O-β-D-glucoside( 5),respectively. All the compounds exhibited active effects on PPARγ in a concentration-dependent manner( P&lt;0. 01). In addition,compound 1 significantly inhibited the expression of IL-1β mRNA and secretion of IL-8 on HT-29 cells inflammation model( P&lt;0. 001); both compounds 2 and 3 effectively inhibited the expression of IL-1β,TNF-α,IL-8 mRNA and secretion of IL-8( P&lt;0. 01 or P&lt;0. 001),although at different extent; compound 4 significantly inhibited the expression of IL-1β and TNF-α mRNA( P&lt;0. 01 or P&lt;0. 001),while compound 5 inhibited the expression of IL-1β mRNA obviously( P&lt;0. 001). In conclusion,the diterpenoids 1-5 isolated from S. pubescens have the PPARγ activation activities and potential effects of anti-UC in vitro.

LncRNA GAS5-promoted apoptosis in triple-negative breast cancer by targeting miR-378a-5p/SUFU signaling.

Long-chain noncoding RNAs (lncRNAs) are involved in regulating the sensitivity of cancer cells to chemotherapeutic drugs, but the specific mechanism of action is not well understood. The aim of this study was to investigate the effect of lncRNA growth-stasis specific transcript 5 (GAS5) on triple-negative breast cancer (TNBC). Quantitative real-time polymerase chain reaction and flow cytometry were used to screen lncRNA associated with tumor resistance. Double luciferase reporter gene assay, flow cytometry, and Western blot assay were used to determine whether miRNA 378a-5p and SUFU were involved in tumor cell apoptosis induced by lncRNA GAS5. A mouse model of subcutaneous xenografts was established to investigate the relationship between lncRNA GAS5 and tumor resistance in vivo. In this study, the expression of lncRNA GAS5 was significantly downregulated in cells treated with paclitaxel (PTX) or cisplatin (CIS). Furthermore, TNBC cells with low expression of lncRNA GAS5 had a lower percentage of apoptosis under stress conditions, especially in serum-free medium. More interestingly, the expression level of lncRNA GAS5 in TNBC patients was associated with tumor resistance to PTX and CIS. In addition, RNA immunoprecipitation experiments confirmed that lncRNA GAS5 and miR-378 could directly bind to each other. Moreover, the miR-378a-5p target of SUFU could promote lncRNA GAS5-induced apoptosis of TNBC cells. Finally, lncRNA GAS5 overexpressed MDA-231R could enhance the sensitivity of TNBC to PTX. The above results confirmed that lncRNA GAS5 could induce apoptosis in TNBC cells by targeting miR-378a-5p/SUFU signaling.

Receptor-Interacting Protein Kinase 1 Promotes Cholangiocarcinoma Proliferation And Lymphangiogenesis Through The Activation Protein 1 Pathway.

PurposeReceptor-interacting protein kinase 1 (RIPK1) is an important upstream regulator of multiple cell signaling pathways including inflammatory signals. RIPK1 is reported to be closely associated with the prognostic implications of cancer, especially epithelial tumors. But its role in proliferation and lymphangiogenesis in cholangiocarcinoma (CCA) remains unclear and requires further investigation.Patients and methodsExpression of RIPK1 in human CCA tissues and CCA cell lines (QBC939, HUH28 and CCPL-1) was measured using qPCR, immunoblotting and immunohistochemistry. Silencing of RIPK1 was achieved by transduction of CCA cells via lentiviral plasmids (LV3-H1/GFP&Puro) encapsulating RIPK1 shRNA (LV-shRIPK1) or negative control shRNA (LV-shNC), and puromycin was used to select stable colonies. Proliferation and lymphangiogenesis were assessed in vitro by CCK-8 and matrigel-based tube formation assays, respectively. Activity of the activation protein-1 (AP-1) was evaluated by double-luciferase reporter gene assay. Protein expression of JNK, P38MAPK, ERK1/2, AP-1, P-AP-1, E-cadherin, N-cadherin and vascular endothelial growth factor-C (VEGF-C) was measured by immunoblotting or ELISA. An orthotopic CCA model in null mice was generated by transplanting QBC939 LV-shRIPK1, LV-shNC and control cells to further evaluate the role of RIPK1 on lymphangiogenesis in vivo. Immunohistochemistry was utilized to evaluate the expression of RIPK1 and VEGF-C, and tumor lymphatic vessels in the CCA model mice.ResultsUpregulated expression of RIPK1 in CCA tissues was closely related to tumor size, lymph node metastasis and poor prognosis. RIPK1 promoted proliferation and lymphangiogenesis in CCA cells, and regulated the activation of JNK and P38MAPK-mediated AP-1/VEGF-C pathway. Finally, in vivo animal experiments in the orthotopic CCA mouse model further confirmed the function of RIPK1 in lymphangiogenesis.ConclusionThis is the first report demonstrating the role of RIPK1 in proliferation and lymphangiogenesis through the MAPK (JNK and P38MAPK)- AP-1 pathway in CCA.

Effects and mechanism of microRNA-1973 on proliferation of hepatocellular carcinoma cells

Objective To investigate the effect of microRNA (miRNA, miR)-1973 expression on the proliferation of hepatocellular carcinoma (HCC) and its underling mechanism. Methods The expression of miR-1973 was detected in hepatoma tissues and matching non-tumor tissues by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). Then the relationship between miR-1973 expressions and the prognosis of liver cancer patients was analyzed. Followed cell transfection targeted regulation the expression of miR-1973, cell counting kit-8 (CCK-8) was used to analyze its effect on the proliferation of HCC cells. Meanwhile, RT-qPCR and Western blotting were employed to detect the changes of suppressor of cytokine signaling 2 (SOCS2). Double luciferase reporter gene assay was applied to examine the fluorescence intensity changes in the 3’ non-coding region of SOCS2. Results The expression of miR-1973 in liver cancer tissues was significantly higher than that in adjacent tissues (t=4.216, P 0.05). Conclusion miR-1973 was over-expression in HCC tissues, and inhibited the proliferation of cancer cells through SOCS2. miR-1973 may be a new target for the treatment of HCC. Key words: MicroRNA-1973; Hepatocellular carcinoma; Proliferation; Suppressor of cytokine signaling 2

LncRNA HULC promots HCC growth by downregulating miR-29

Objective: To explore the effects of lncRNA HULC on hepatocellular carcinoma (HCC) growth by down-regulating miR-29. Methods: The expression levels of HULC and miR-29 in HCC tissues and cells were detected by real-time quantitative PCR (RT-qPCR), and the correlation analysis was performed. After HCC cells were transfected with HULC overexpressed plasmid or siRNA, the expressions of miR-29 and its target gene SETDB1 were determinate by RT-qPCR. According to the bioinformatic prediction of the miR-29 binding site in the HULC sequence, the report gene plasmids were constructed. The HCC cells were co-transfected with miR-29 mimics or miR-29 inhibitor, and the HULC targeted regulation of miR-29 was verified by dual luciferase reporter assay. The effect of miR-29 on the HULC-mediated proliferation in HCC cells was detected by cell count kit 8 (CCK-8) experiment. Expression of tumor proliferation antigen Ki-67 was detected by RT-qPCR.The Hep3B cells were inoculated in mice and miR-29 mimics and miR-29 negative control (NC) further injected into the lesions. The tumor volume was observed, and the expressions of tumor proliferation antigen ki-67 in tumor tissues were detected by immunohistochemical staining. Results: The expression of HULC was significantly up-regulated while the expression of miR-29 was significantly down-regulated in HCC tissues and cells (P<0.01). The level of HULC was negatively correlated with miR-29 in tumor tissues (r=-0.754, P<0.01) and HCC cells (r=-0.865, P<0.05). The in vitro experiments showed that, compared with the blank control group, the expression of miR-29 in HULC overexpressed Huh7 cells was significantly reduced, while the mRNA level of miR-29 target gene SETDB1 was increased (P<0.01). The expression of miR-29 was significantly increased in HULC deleted Hep3B cells, while the mRNA expression of SETDB1 was decreased (P<0.01). Double luciferase reporter gene assay showed that miR-29 mimics significantly inhibited the luciferase activity of Hep3B cells transfected with HULC wide type (psi-HULC-WT) plasmid but had no effect on Hep3B cells transfected with mutant plasmid (psi-HULC-Mut). However, the miR-29 inhibitor antagonized the inhibitory effect of miR-29 mimics on luciferase activity of psi-HULC-WT (P<0.01). Cell proliferation experiments showed that, compared with the control group, the proliferation ability of miR-29 mimics overexpressed Huh7 cells was significantly reduced.After 24, 48 and 72 hours of treatment, the proliferation rates of Huh7 cells in the HULC overexpressed group were (43.87±3.82)%, (83.45±7.46)% and (123.34±8.67)%, respectively, significantly higher than (13.45±1.77)%, (23.54±1.37)% and (38.21±2.09)% of control group (P<0.05). After treatment for 48 and 72 hours, the proliferation rates of miR-29 mimics transfected Huh7 cells were (57.10±1.94)% and (73.76±3.46)%, respectively, significantly lower than (83.45±7.46)% and (123.34±8.67)% of control group (P<0.05). After treatment for 48 and 72 hours, the proliferation rates of Huh7 cells transfected with miR-29 mimics and miR-29 inhibitor group were (76.45±3.24)% and (89.37±4.37)%, respectively, significant higher than (57.10%±1.94)% and (73.76±3.46)% of the control group (P<0.05). After 48 h transfection, the expression of Ki-67 in Huh7 transfected with miR-29 mimics was significantly inhibited compared with the control group (P<0.01). However, the expression of Ki-67 mRNA was increased in Huh7 cells transfected with miR-29 inhibitor (P<0.01). The results of in vivo experiments showed that the tumor volumes of the control group, miR-29 mimics group and miR-29 mimics + miR-29 inhibitors group were (504.0±19.6) mm(3), (310.0±24.3) mm(3) and (483.7±21.2) mm(3), respectively. Injection of miR-29 mimics reduced while miR-29 inhibitor promoted tumorigenesis ability of Huh7 in nude mice (P<0.01). The immunohistochemical staining showed that the average optical density values of Ki-67 protein in tumor tissues of the control group, miR-29 mimics group and miR-29 analogue+ miR-29 inhibitor group were 0.65±0.08, 0.36±0.07 and 0.56±0.06, respectively. The expression level of Ki-67 protein in miR-29 mimics group was significantly reduced (P<0.01) while increased in the miR-29 mimics+ miR-29 inhibitor group (P<0.01). Conclusion: LncRNA HULC promotes HCC growth by down-regulating miR-29.

Effect of long chain non-coding RNA H19 on the migration and invasion of oral cancer cells and its molecular mechanism

To investigate the effect of the long chain non-coding RNA H19 (lncRNA H19) on the invasion and migration of oral cancer cells and its related molecular mechanism. The expression levels of lncRNA H19, miR-107, and cyclin-dependent kinase 6 (CDK6) in the immortalized oral epithelial cell line HIOEC and the oral cancer cell line CAL27 were detected by real-time quantitative polymerase chain reaction. CAL27 cells were transfected with siRNA H19, miR-107 mimics, pcDNA H19, or anti-miR-107, and the effects of H19 and miR-107 on the invasion and migration of cells were examined via Transwell assay. The TargetScan database predicted the targeting of H19, miR-107, and CDK6. Double luciferase reporter gene assay was performed to detect interactions among H19, miR-107, and CDK6. Western blot analysis was conducted to examine the effects of H19 and miR-107 on the protein level of the target gene CDK6. Compared with that in HIOEC cells, the expression of H19 was significantly increased in CAL27 cells (P<0.05). After transfection with siRNA H19, the expression of H19 decreased, and the invasion and migration ability of CAL27 cells were inhibited (P<0.05). H19 could bind specifically to the 3'-UTR of miR-107 to modulate the expression of miR-107. Compared with that in HIOEC cells, the expression of miR-107 significantly decreased in CAL27 cells (P<0.05). The expression of miR-107 increased after transfection with siRNA H19, and anti-mir-107 co-transfection could promote the invasion and migration ability of siRNA H19 in CAL27 cells (P<0.05). Compared with that in HIOEC cells, CDK6 expression significantly increased in CAL27 cells (P<0.05), and the expression level of the gene was coregulated by H19 and miR-107 (P<0.05). lncRNA H19 plays an important role in the development of oral cancer. It can regulate the invasion and migration of oral cancer cells by targeting the miR-107/CDK6 signaling axis.

Effects of miR-144 on proliferation, apoptosis and cisplatin resistance by targeting MYCN in pediatric neuroblastoma

Objective: To investigate the effects and mechanisms of miR-144 on proliferation, apoptosis and cisplatin (DDP) resistance of neuroblastoma cells. Methods: Real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the mRNA expressions of miR-144 and MYCN in neuroblastoma cell lines, including SH-SY5Y and SK-N-SH, and human umbilical vein endothelial cells HUVEC. The miR-negative control, miR-144 mimics, si-negative control, si-MYCN, miR-144 mimics and pcDNA, miR-144 mimics and pcDNA-MYCN co-transfected SH-SY5Y cells were described as miR-NC, miR-144, si-NC, si-MYCN, miR-144+ pcDNA and miR-144+ pcDNA-MYCN group, respectively. The half maximal inhibitory concentration (IC(50)) and cell proliferation were detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay. The protein expressions of MYCN, p21, cyclin D1, Bax, Bcl-2 were analyzed by western blot. Cell apoptosis was detected by flow cytometry. The cell fluorescence activity was detected by double luciferase reporter gene assay. Results: Compared with HUVEC cells, the expressions of miR-144 in neuroblastoma cells SH-SY5Y and SK-N-SH significantly decreased, while the mRNA and protein expression of MYCN significantly increased. The IC(50) of DDP was 9.16 μg/ml in SH-SY5Y cells. The absorbance value in 490nm (A(490) value) of miR-144 group was 0.30±0.03, significantly lower than 0.46±0.03 of miR-NC group. The cell apoptotic rate of miR-144 group was 26.94%±2.01%, significantly higher than 9.68%±0.52% of miR-NC group. The IC(50) value of DDP in miR-144 group was 2.95±0.26, significantly lower than 9.23±0.61 of miR-NC group. The expressions of p21, cyclin D1, Bax, Bcl-2 in miR-NC and miR-144 group were 2.67±0.19, 0.41±0.04, 2.12±0.21, 0.18±0.01 and 1.01±0.07, 1.00±0.06, 1.00±0.05, 1.00±0.06, respectively, with statistical significance (all P<0.05). Knockdown of MYCN showed the similar effects with those of miR-144 overexpression in SH-SYSY cells. MiR-144 significantly inhibited the fluorescence activity of ectopic MYCN expressing cells and negatively regulated the expression of MYCN. Overexpression of MYCN can reverse the effects of miR-144 on proliferation inhibition, apoptosis promotion and sensitization of SH-SY5Y cells to DDP. Conclusion: MiR-144 inhibits proliferation, promotes apoptosis and enhances the sensitivity of neuroblastoma cells to DDP through targeting MYCN, which provides a potential treatment for neuroblastoma.

Mechanism of lnc-AC079612.1.1-1∶1 in hepatic metastasis of colon cancer

Objective To investigate the mechanism of lnc-AC079612.1-1∶1 in the metastasis of colorectal cancer by regulating miR-1915 expression and provide a theoretical basis for new therapeutic targets of colon cancer. Methods Continuously harvested 3 pairs of primary tumor and hepatic metastases of patients with synchronous colon cancer with liver metastasis. LncRNA+ mRNA Human Gene Expression Microarray V4.0 and 4×180K Expression Microarray were used to detect the Expression profile of LncRNA in primary colon cancer and matched liver metastases. The detection of expression profile chip was used to find some lncRNAs that may be closely associated with colon cancer liver metastasis, and through the literature retrieval, the author preliminarily analyzed the co-expression encoding genes of lncRNAs, in order to find lncRNAs that may play key roles in the process of colon cancer liver metastasis. The effect of lnc-AC079612.1.1-1∶1 on the proliferation capacity of colon cancer cell lines was detected in SW480 cell lines and SW620 cell lines of colon cancer through CCK-8 experiment. Effects of lnc-AC079612.1.1-1∶1 on the migration and invasion of colon cancer cells were examined by Transwell cell invasion assay. Through TargetScan, Miranda, LNCipedia and other web tools, miRNAs that may bind to lncRNA and o-6-methylguanine-DNA methyl transferase (MGMT) were predicted. Double luciferase reporter gene assay was used to detect the interaction between miR-1915 andlnc-AC079612.1.1-1∶1. SPSS 22.0 statistical software was used to analyze the data. The measurement data were expressed as (±s). T test was compared between the two groups, and multiple groups were compared with F test. Results The expression of lnc-AC079612.1-1∶1 was 3.94 times higher in the liver metastases than in the primary tumor, and expression of MGMT was 3.74 times higher in the liver metastases than in the primary tumor. The results showed that there was a significant co-expression relationship between the lncRNA and o-6-methylguanine DNA transferase (MGMT) gene, and the co-expression correlation coefficient was 0.994(P<0.001). The over expression of lnc-ac079612.1.1-1∶1 could significantly enhance the proliferation capacity of SW480 and SW620 cell lines of colon cancer through the CCK-8 experiment. The over expression of lnc-ac079612.1.1-1∶1 could promote the invasion and metastasis of SW480 and SW620 cell lines of colon cancer through Transwell cell invasion experiment. MirR-1915-3p was the only miRNA that predicted to be combined with lnc-ac079612.1-1∶1 and MGMT through TargetScan, Miranda, LNCipedia and other web tools. Lnc-ac079612.1.1-1∶1 was found to bind to miR-1915 by double luciferase assay. Conclusion Lnc-ac079612.1.1-1∶1may participate in the liver metastasis process of colon cancer by regulating MGMT, and may play a role in the liver metastasis of colon cancer through the action of mir-1915 on MGMT. Key words: Colonic neoplasms; Micro RNAs; Neoplasm invasiveness; Liver metastasis; IncRNA

MicroRNA‑125 inhibits RKO colorectal cancer cell growth by targeting VEGF.

Colorectal cancer (CRC) is one of the major types of cancer and causes of mortality worldwide, and it remains the third most common cause of cancer‑associated mortality worldwide. MicroRNAs (miRNAs) are a class of small RNAs, which have been shown to be associated with CRC. In the present study, an MTT assay and proliferating cell nuclear antigen(PCNA) protein examination assay were performed to detect RKO cell viability. Hoechst staining, and caspase‑3 activity and BrdU incorporation assays were performed to detect RKO cell apoptosis, respectively. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blot analyses were used to analyze the expression of cyclooxygenase‑2 (COX‑2). Western blot analysis was also used to analyze the expression of vascular endothelial growth factor(VEGF) and mitogen‑activated protein kinase(MAPK) signal molecules, including extracellular signal‑regulated kinase(ERK), p38 and c‑Jun N‑terminal kinase (JNK). The target genes of miR-125 were predicted using a double luciferase reporter gene assay. The results of the MTT assay showed that RKO cell viability was decreased by an miRNA-125 mimic and increased by the miRNA-125 inhibitor. The RKO cell viability was significantly correlated with the expression of PCNA. The migration of RKO cells was significantly downregulated in the miR-125 mimics‑transfected cells and upregulated in the miRNA-125 inhibitor‑transfected cells. The results of Hoechst staining and the caspase‑3 activity and BrdU incorporation assays showed that RKO cell apoptosis was increased following miRNA-125 mimic transfection and decreased following miRNA-125 inhibitor transfection. The results of the RT‑qPCR and western blot analysis showed that the expression of COX‑2 was increased in the miR-125 mimic‑transfected cells and decreased in the miR-125 inhibitor‑transfected cells. Using an online miRNA target prediction database, the double luciferase reporter gene assay showed that miR‑125 targeted and inhibited the expression of VEGF through target sites located in the 3'untranslated region of VEGF mRNA. In conclusion, the abnormal expression of miR‑125 was found to be closely associated with CRC. Therefore, miR‑125 may be a novel therapeutic target for CRC.

Interaction of heat shock protein 60 (HSP60) with microRNA in Chinese mitten crab during Spiroplasma eriocheiris infection

Heat shock protein 60 from the Chinese mitten crab Eriocheir sinensis (EsHSP60) was previously identified in relation to Spiroplasma eriocheiris infection by isobaric tags for relative and absolute quantitation labelling followed by liquid chromatography-tandem mass spectrometry. In the present study, to validate the immune function of this protein, the cDNA of the EsHSP60 gene was cloned. Various crab tissues were assessed using real-time PCR, which showed that EsHSP60 transcription occurred in all tissues examined. The expression profiles of EsHSP60 in haemolymph at transcription and protein levels when infected with S. eriocheiris were investigated by real-time PCR and Western blot analysis, respectively. A significant increase of EsHSP60 transcription and protein expression appeared post-injection in response to S. eriocheiris infection when compared to the control group. The double-luciferase reporter gene assay showed that the microRNA PC-533-3p interacted with the 3'-untranslated region of EsHSP60 and inhibited the translation of EsHSP60. The expression profiles of PC-533-3p during S. eriocheiris infection were also investigated by real-time PCR. However, the change tendency of PC-533-3p was opposite to that of the EsHSP60 after S. eriocheiris challenge. These data indicate that the EsHSP60 proteins may play an important role in mediating the immune responses of E. sinensis to an S. eriocheiris challenge.