Effects of resveratrol on viability,invasion and autophagy of osteosarcoma MG-63 cells by up-regulating miR-34a

AIM: To investigate the effects of resveratrol on the viability, invasion and autophagy of osteosarcoma MG-63 cells and the regulatory effect of microRNA-34a (miR-34a). METHODS: MG-63 cells were divided into 6 groups:control group and resveratrol treatment groups at doses of 10, 20, 40, 60 and 80 μmol/L. MTT assay, Transwell chamber method and Western blot were used to detect the effects of resveratrol on the viability, invasion ability and expression of autophagy-related proteins in the osteosarcoma cells. The effect of resveratrol at different concentrations on the expression of miR-34a in the osteosarcoma cells was detected by RT-qPCR. The effects of miR-34a mimic and miR-34a mimic negative control (miR-34a NC) transfection on the viability and invasion ability of osteosarcoma cells after treated with resveratrol at different concentrations were analyzed. The effects of miR-34a mimic transfection on autophagy-related proteins LC3-I, LC3-Ⅱ and beclin-1 were determined by Western blot. RESULTS: Compared with control group, resveratrol inhibited the viability and invasion ability of the MG-63 cells and promoted autophagy (P<0.05). Resveratrol up-regulated the expression of miR-34a in the MG-63 cells in a dose-dependent manner (P<0.05). In addition, the ratio of LC3-Ⅱ/LC3-I was increased, and beclin-1 was up-regulated (P<0.05). Co-treatment with miR-34a mimic and resveratrol increased inhibitory effects of resveratrol on the viability and invasion ability and invasion of the MG-63 cells and also promoted autophagy. CONCLUSION: Resveratrol inhibits the viability and invasion of osteosarcoma MG-63 cells and promotes auto-phagy by up-regulating miR-34a expression.     

miR-204 inhibits proliferation of Hodgkin lymphoma cells by targeting Sirt1/p53 signaling pathway

AIM: To investigate the effect of microRNA-204 (miR-204) on the proliferation of Hodgkin lymphoma cells and the underlying mechanism. METHODS: The expression of miR-204 and Sirt1 mRNA in Hodgkin lymphoma tissues was detected by RT-qPCR. After transfection with miR-204 mimic, Sirt1 siRNA and miR-204 mimic+pcDNA3.1-Sirt1 into the L428 cells, the cell viability and BrdU incorporation were measured by CCK-8 assay and BrdU assay, respectively. The protein levels of Sirt1 and acetylated p53 (ac-p53) were determined by Western blot.The targeting relationship between miR-204 and Sirt1 was verified by double luciferase reporter assay. RESULTS: The low expression of miR-204 and the high mRNA expression of Sirt1 were found in the Hodgkin lymphoma tissues. Compared with control group, the cell viability, BrdU incorporation and the protein levels of Sirt1 and ac-p53 were significantly decreased after L428 cells were transfected with miR-204 mimic or Sirt1 siRNA (P<0.05). Compared with miR-204 mimic alone group, the cell viability, BrdU incorporation and the protein levels of Sirt1 and ac-p53 were increased after L428 cells were co-transfected with miR-204 mimic and pcDNA3.1-Sirt1 (P<0.05). The results of double luciferase reporter assay confiermed that Sirt1 was the target gene of miR-204. CONCLUSION: The inhibitory effect of miR-204 on the proliferation of L428 cells may be achieved by inhibiting the expression of Sirt1 and promoting the up-regulation of ac-p53.     

miR-15a-5p inhibits proliferation and migration of human hepatocellular carcinoma SMMC-7721 cells

AIM: To observe the influence of high expression of miR-15a-5p on the proliferation and migration of human hepatocellular carcinoma SMMC-7721 cells.METHODS: The miR-15a-5p oligonucleotide, which was reconstructed with additional restriction sites of EcoR Ⅰ and Hind Ⅲ, was chemically synthesized and confirmed by sequencing. The miR-15a-5p eukaryotic expression system was constructed by pcDNA6.2-GW/Em-GFP-pre-miR-15a-5p plasmid. The miR-15a-5p was transfected into the SMMC-7721 cells transiently by plasmid, and quantified by quantitative real-time PCR at the mRNA level. The cell viability was measured by CCK-8 assay, and the living cell counting was performed by the method of Trypan blue exclusion. The migration ability of the SMMC-7721 cells with high expression of miR-15a-5p was detected by wound healing test.RESULTS: The sequence of miR-15a-5p oligonucleotide 100% matched the designed sequence. Compared with control group, the miR-15a-5p expression was increased significantly (P<0.05). The viability, the living cell number and the migration ability of the SMMC-7721 cells were decreased in high expression of miR-15a-5p group with statistically significant difference (P<0.05).CONCLUSION: The abilities of proliferation and migration in human hepatocellular carcinoma SMMC-7721 cells are decreased by high expression of miR-15a-5p.     

Induction of apoptosis by c-myc antisense oligonucleotide in osteosarcoma cell MG-63

AIM: To study the induction of apoptosis by c-myc antisense oligonucleotide in osteosarcoma cell (MG-63).METHODS: The designed c-myc antisense oligonucleotide fragment was transfected into human osteosarcoma MG-63 cells. The cell growth and apoptosis were measured by the methods of MTT, FCM, HE staining and transmission electron microscopy.RESULTS: The results showed that the proliferation of human osteosarcoma MG-63 cells was inhibited and apoptotic rate was 37.92% when treated with c-myc antisense oligonucleotide at the does of 10.0 μmol/L for 48 h. c-myc antisense oligonucleotide (10.0 μmol/L) also inhibited the expression of c-myc protein.CONCLUSION: c-myc antisense oligonucleotide is able to induce apoptosis in human osteosarcoma MG-63 cells.     

Long noncoding RNA ZFAS1/miR-150/ROCK1 axis regulates proliferation and migration of vascular smooth muscle cells

AIM: To investigate whether long noncoding RNA ZNFX1 (zinc finger NFX1-type containing 1) antisense RNA 1 (ZFAS1) promotes the proliferation and migration of vascular smooth muscle cells (VSMCs) by regulating microRNA-150 (miR-150)/ROCK1, and the involving mechanism of atherosclerosis. METHODS: Platelet-derived growth factor-BB (PDGF-BB) was used to induce proliferation and migration of VSMCs. Real-time PCR was used to detect the content of ZFAS1 in the VSMCs. After further down-regulating the expression of ZFAS1 by siRNA, the viability of VSMCs was detected by MTT assay, and the proliferation was measured by EdU staining. The migration ability of VSMCs was detected by Transwell method. The expression levels of miR-150 and ROCK1 were detected by RT-qPCR, and the protein level of ROCK1 was determined by Western blot. Luciferase reporter assay was used to confirm that ROCK1 was the target gene of miR-150. Finally, miR-150 expression was inhibited, and the proliferation and migration ability of VSMCs and expression of ROCK1 after down-regulation of ZFAS1 expression were examined. RESULTS: PDGF-BB up-regulated the expression of ZFAS1 in the VSMCs. After down-regulating the expression of ZFAS1, the proliferation and migration abilities of VSMCs were inhibited (P<0.05), the expression level of miR-150 was increased (P<0.05), and the expression level of ROCK1 was decreased (P<0.05). The results of luciferase reporter assay showed that miR-150 directly targeted ROCK1. Inhibition of miR-150 expression attenuated the inhibition of proliferation and migration of VSMCs by ZFAS1 expression knock-down (P<0.05) and up-regulated the expression level of ROCK1 (P<0.05). CONCLUSION: ZFAS1 promotes the proliferation and migration of VSMCs induced by PDGF-BB by regulating miR-150/ROCK1.     

Effect of miR-181b on cell proliferation and expression of Bcl-2 and SP1 in HepG2 cells

AIM: To investigate the role of miR-181b in the expression of Bcl-2 and SP1 at mRNA and protein levels in the human hepatoma G2 cells (HepG2), and to explore the effect of miR-181b on the regulation of HepG2 cell proliferation. METHODS: The synthetic double-strand complementary DNA based on the sequence of miR-181b was inserted into the vector of miRNASelect^TM pEGP-miR. The microRNA high-expression plasmid was cloned, and the sequences were identified. The miR-181b plasmid was transfected into HepG2 cells with liposomes. The stable cell line was screened by puromycin. The mRNA and protein levels of Bcl-2 and SP1 were measured by RT-PCR and Western blotting, respectively. Methyl thiazolyl tetrazolium (MTT) method was used to analyze the proliferation of HepG2 cells. RESULTS: The Western blotting results showed that miR-181b inhibited the protein expression of Bcl-2 and SP1. The result of RT-PCR also indicated that the mRNA expression of Bcl-2 and SP1 was suppressed. Compared with the control, the growth rate of HepG2 with high expression of miR-181b was significantly decreased.CONCLUSION: miR-181b inhibits the proliferation of HepG2, which may be related to the down-regulation of Bcl-2 and SP1.     

miR-542-5p down-regulates IEC-6 cell proliferation induced by sphingosine-1-phosphate

AIM:To observe the effects of miR-542-5p on the proliferation of rat small intestine crypt epithe-lial IEC-6 cells induced by sphingosine-1-phosphate (S1P).METHODS:Two IEC-6 cell lines (SphK1-IEC-C1 and SphK1-IEC-C2) were established,which expressed sphingosine kinase-1(SphK1) stably.Radioactive tracer was used to detect SphK1 activity and S1P secretion.The cell proliferation was observed by cell counting and described by drawing growth curve,and the cell cycle analysis was carried out by flow cytometry.The level of miR-542-5p was evaluated by RT-qPCR.RESULTS:Compared with control vector cells without SphK1 cDNA,both SphK1-IEC-C1 and SphK1-IEC-C2 cell lines showed that Sphk1 was elevated,both intracellular and extracellular S1P increased dramatically,the rate of cell growth was faster,the percentage of the cells in S phase increased,and miR-542-5p expression decreased.S1P (0.5~10 μmol/L) led to the decrease in miR-542-5p expression.On the contrary,SphK1 silencing resulted in the increase in miR-542-5p expression in the IEC-6 cells.The miR-542-5p was elevated in SphK1-IEC-C1 cells and SphK1-IEC-C2 cells,which caused the decrease in the percentage of the cells in S phase.The cell growth rate in the above-mentioned 2 cell lines decreased compared with negative control group.CONCLUSION:In IEC-6 cells,S1P promotes proliferation by inhibiting miR-542-5p expression,which induces the cell cycle transferring from G₁ phase to S phase.     

Role of miRNA-24 in regulation of endothelial nitric oxide synthase expression and vascular endothelial cell proliferation

AIM：To investigate whether miRNA-24 is involved in the regulation of endothelial nitric oxide synthase (eNOS) expression and vascular endothelial cell proliferation. METHODS：A plasmid that highly expressed miRNA-24 was constructed, and was transfected into the human umbilical vein endothelial cells (HUVECs) by liposome. The cell proliferation was detected by MTT assay. The expression of eNOS and Sp1 at mRNA and protein levels was exa-mined by real-time PCR, immunohistochemistry and Western blotting.RESULTS：Compared with control group, the proliferation of endothelial cells in miRNA-24 group was significantly decreased by 41.97 % (0.47±0.04 vs 0.81±0.03, P<0.01), and the expression of eNOS at mRNA and protein levels was decreased by 44.8% (0.48±0.01 vs 0.87±0.03, P<0.05) and 71.92% (0.16±0.06 vs 0.57±0.08, P<0.05), respectively. Meanwhile, the mRNA and protein levels of Sp1 were significantly decreased by 53.00% (0.45±0.02 vs 0.93±0.01, P<0.05) and by 62.31% (0.13±0.07 vs 0.31±0.09, P<0.05), respectively. In miRNA-24 inhibitor group, the above indexes were decreased compared with control group, but significantly increased compared with miRNA-24 group. CONCLUSION：miRNA-24 significantly inhibits the proliferation of HUVECs and the eNOS expression. Sp1 possibly acts as one of the important factors in the regulation of eNOS expression by miRNA-24.     

Inhibition of miR-9 expression suppresses proliferation,invasion and migration of nasopharyngeal carcinoma cells

AIM: To investigate the effects of down-regulated miR-9 expression on the proliferation, invasion and migration of nasopharyngeal carcinoma (NPC) cells. METHODS: Human NPC CNE1 and CNE2 cells were transfected with the inhibitor of miR-9 by Lipofectamine to down-regulate the expression of miR-9, and the cells transfected with an inhibitor control were also set up. The cell proliferation and cell cycle were evaluated by CCK-8 assay and flow cytometry. The cell invasion and migration abilities were detected by Transwell invasion and wound-healing assays. Immunoblotting was applied to analyze the levels of the proteins. RESULTS: Compared with control group, inhibition of miR-9 expression in the NPC cells by transfection of the miR-9 inhibitor significantly decreased the proliferation ability (P<0.05). The percentages of the cells in G0/G1 phase ［CNE2: (57.96±1.39)% vs (47.93±1.76)%, P<0.05; CNE1: (51.24±0.88)% vs (48.29±0.39)%, P<0.05］ were significantly increased. The migration distances ［CNE2: (186.50±7.94)μm vs (247.56±15.56)μm, P<0.05; CNE1: (139.06±16.73)μm vs (230.66±14.27)μm, P<0.01］ and the invasion ability of the CNE2 cells (43.00±3.17 vs 65.80±5.20, P<0.01) were also significantly inhibited. Moreover, the tumor cells transfected with the inhibitors produced lower β-catenin. CONCLUSION: Inhibition of miR-9 expression suppresses the proliferation, invasion and migration of nasopharyngeal carcinoma cells.     

Effect of SMYD3 over-expression on miR-124 expression and proliferation ability in human intrahepatic cholangiocarcinoma cells

AIM：To explore the effect of SET and MYND domain-containing protein 3 (SMYD3) over-expression on miR-124 expression and proliferation ability of human intrahepatic cholangiocarcinoma cells. METHODS：Transient transfection of SMYD3 eukaryotic expression plasmid into human intrahepatic cholangiocarcinoma cell line HCCC-9810 were performed. The expression of SMYD3 at mRNA and protein levels was measured by qRT-PCR and Western blotting, respectively. The expression of miR-124 was detected by qRT-PCR, and the methylation status of miR-124 gene was determined by methylation-specific PCR. Cell proliferation was examined by CCK-8 assay and colony formation experiment. RESULTS：After transfected with SMYD3 eukaryotic expression plasmid, the over-expression of SMYD3 in HCCC-9810 cells was observed. Compared with the blank cells, the expression level of miR-124 was significantly decreased and miR-124 gene promoter methylation was significantly increased. In addition, SMYD3 over-expression significantly promoted the proliferation of HCCC-9810 cells. CONCLUSION：The transient transfection of SMYD3 plasmid increases the methylation of miR-124 gene promoter and induces under-expression of miR-124. Over-expression of SMYD3 promotes the proliferation of cholangiocarcinoma cells.     

miR-556-3p regulates viability,migration and invasion of endometrial cancer cells by targeting SASH1

AIM To investigate whether microRNA-556-3p （miR-556-3p） regulates the viability, migration and invasion of endometrial cancer cells by targeting SASH1 gene. METHODS The expression of miR-556-3p, and the mRNA and protein levels of SASH1 in endometrial cancer tissues were detected by RT-qPCR and Western blot. Anti-miR-556-3p or pcDNA-SASH1 was transfected into endometrial cancer Ishikawa cells. The cell viability was detected by MTT assay, the migration and invasion abilities of the cells were detected by Transwell chamber method, and the protein expression levels of cyclin D1, p21, matrix metalloproteinase-2 （MMP-2） and MMP-9 were detected by Western blot. StarBase prediction and dual-luciferase reporter experiments were used to analyze the targeting relationship between miR-556-3p and SASH1. Anti-miR-556-3p and si-SASH1 were co-transfected into the Ishikawa cells, and their effects on cell viability, migration and invasion were examined by the methods described above. RESULTS Compared with adjacent tissues, the expression of miR-556-3p in endometrial cancer tissues was increased significantly, and the expression of SASH1 at mRNA and protein levels was decreased significantly （P<0.05）. Inhibition of miR-556-3p expression or induction of SASH1 over-expression obviously reduced the viability of Ishikawa cells, the number of migratory cells, the number of invasive cells and the protein levels of cyclin D1, MMP-2 and MMP-9, and dramatically increased the protein level of p21 （P<0.05）. miR-556-3p targeted SASH1 and negatively regulated its expression. Knock-down of SASH1 expression reversed the inhibitory effect of miR-556-3p expression inhibition on the viability, migration and invasion of Ishikawa cells. CONCLUSION Inhibition of miR-556-3p expression suppresses the viability, migration and invasion of endometrial cancer cells. The mechanism is related to the regulation of its target gene SASH1.     

Nisin induces apoptosis of human osteosarcoma MG63 cells via oxidative stress

AIM To investigate the effect of nisin on apoptosis of human osteosarcoma MG63 cells and its related oxidative stress mechanism. METHODS The MG63 cells were cultured in the medium containing different concentrations of nisin with or without antioxidant N-acetyl-L-cysteine （NAC）. The cell viability was measured by CCK-8 assay. Apoptosis was analyzed by flow cytometry with annexin-V/PI staining. The production of intracellular reactive oxygen species （ROS） was detected by redox-sensitive dye 2',7'-dichlorofluorescein diacetate （DCFH-DA）. The 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl benzimidazolyl carbocyanine iodide （JC-1） was used to detect the changes of mitochondrial membrane potential （MMP）. The protein levels of apoptosis-associated molecules Bax, Bcl-2 and cleaved caspase-3 were determined by Western blot. RESULTS Nisin decreased the viability of MG63 cells and promoted the apoptosis in a dose-dependent manner. It also up-regulated the protein level of cleaved caspase-3, increased the protein expression ratio of Bax/Bcl-2, triggered a large amount of intracellular ROS generation and reduced the MMP （P<0.05）. Moreover, antioxidant NAC significantly inhibited nisin-induced apoptosis of MG63 cells, down-regulated the protein level of cleaved caspase-3, decreased Bax/Bcl-2 ratio, reduced intracellular ROS level, and restored the MMP （P<0.05）. CONCLUSION Nisin may promote oxidative stress in human osteosarcoma cells, activate mitochondrial apoptosis pathway, and eventually induce apoptosis.     

miR-339 suppresses proliferation of pulmonary arterial smooth muscle cells via regulating IGF2BP1

AIM: The present study aimed to investigate the role of microRNA-339 miR-339 in the proliferation of pulmonary artery smooth muscle cells (PASMCs). METHODS: After treating with angiotensin Ⅱ of different concentrations for 48 h, miR-339 mimic and miR-339 inhibitor were transfected into PASMCs, respectively. CCK-8 assay and viable cell counting were performed to determine cell proliferation. The expression levels of miR-339 and PCNA mRNA were measured by RT-qPCR. The protein levels were detected by Western blot. The interaction between miR-339 and insulin-like growth factor 2 mRNA-binding protein 1(IGF2BP1) was confirmed by luciferase reporter assay. RESULTS: Angiotensin Ⅱ concentration-dependently increased cell proliferation and mRNA expression of PCNA, and decreased miR-339 expression in the PASMCs. Over-expression of miR-339 inhibited cell proliferation and mRNA expression of PCNA in the PASMCs, while mutation of miR-339 promoted cell proliferation and mRNA expression of PCNA in the PASMCs. In addition, miR-339 inhibited cell proliferation in angiotensin Ⅱ-treated PASMCs. Bioinformatics analysis showed that miR-339 targeted the IGF2BP1 3'-UTR, which was confirmed by luciferase reporter assay, and miR-339 negatively regulated the expression of IGF2BP1 in the PASMCs. More importantly, over-expression of IGF2BP1 attenuated the inhibitory effects of miR-339 on cell proliferation and mRNA expression of PCNA in the PASMCs. miR-399 over-expression suppressed phosphorylated p38 protein level but not p38 protein level. CONCLUSION: miR-339 suppresses anti-proliferative effects in PASMCs partly via regulating IGF2BP1 and p38 MAPK signaling pathway.     

Effect of inhibiting lncRNA LINC01503 on viability,migration and invasion of lung cancer cells by targeted regulation of miR-335-5p

AIM To investigate the effects of long non-coding RNA (lncRNA) LINC01503 on the viability, migration and invasion of lung cancer cells and its mechanism. METHODS Human lung carcinoma H1299 cells were divided into si-NC group (transfected with si-NC), si-LINC01503 group (transfected with si-LINC01503), pcDNA group (transfected with pcDNA), pcDNA-LINC01503 group (transfected with pcDNA-LINC01503), miR-NC group (transfected with miR-NC), miR-335-5p group (transfected with miR-335-5p mimics), si-LINC01503+anti-miR-NC group (co-transfected with si-LINC01503 and anti-miR-NC), si-LINC01503+anti-miR-335-5p group (co-transfected with si-LINC01503 and anti-miR-335-5p), miR-NC+WT-LINC01503 group (co-transfected with miR-NC and WT-LINC01503), miR-NC+MUT-LINC01503 group (co-transfected with miR-NC and MUT-LINC01503), miR-335-5p+WT-LINC01503 group (co-transfected with miR-335-5p and WT-LINC01503) and miR-335-5p+MUT-LINC01503 group (co-transfected with miR-335-5p and MUT-LINC01503). The expression of miR-335-5p and LINC01503 was detected by RT-qPCR. Western blot was used to detect protein expression. MTT assay was used to detect cell viability. Transwell assay was used to detect the migration and invasion abilities. Dual-luciferase reporter assay was used to confirm the targeted relationship between LINC01503 and miR-335-5p. RESULTS Compared with normal tissues, the expression of LINC01503 was significantly increased in the lung cancer tissues, and the expression of miR-335-5p was significantly decreased (P<0.05). Compared with stage I/II , the expression level of LINC01503 in the lung cancer tissues of stage III/IV was significantly increased, and the expression of miR-335-5p was significantly decreased (P<0.05). The patients with high expression of LINC01503 had lower short-term survival rates than those with low expression of LINC01503 (P<0.05). Compared with normal human bronchial epithelial cell line BEAS-2B, the expression of miR-335-5p in lung cancer cell lines H1299, A549 and SPC-A-1 were significantly decreased, and the expression of LINC01503 was significantly increased (P<0.05). Over-expression of miR-335-5p and inhibition of LINC01503 expression inhibited the viability, migration and invasion of H1299 cells, and inhibited the protein expression of cyclin D1, matrix metalloproteinase-2 （MMP-2） and MMP-9 (P<0.05). LINC01503 targeted and regulated miR-335-5p expression, and interfering with miR-335-5p expression reversed the inhibitory effect of inhibiting LINC01503 expression on the viability, migration and invasion of H1299 cells. CONCLUSION Inhibition of lncRNA LINC01503 inhibits the viability, migration and invasion of lung cancer cells. The mechanism may be related to the targeted regulation of miR-335-5p.     

miR-105 inhibits cell proliferation,migration and invasion abilities in non-small-cell lung cancer cells by targeting and negative regulation of KIFC1

AIM:To study the effects of microRNA-105(miR-105) on the cell proliferation, migration and invasion abilities of non-small-cell lung cancer (NSCLC) H460 cells, and further to explore its mechanism. METHODS:The expression of miR-105 and kinesin family member C1 (KIFC1) mRNA in the NSCLC tissues and adjacent tissues and cells was detected by RT-qPCR. The protein expression of KIFC1 in the NSCLC tissues, adjacent normal tissues and cells was determined by Western blot. The H460 cells were divided into miR-105 group (transfection with miR-105 mimics), miR-negative control (NC) group (transfection with miR-NC), inhibitor-NC group (transfection with NC of inhibitor), inhibitor-miR-105 group (transfection with miR-105 inhibitor), si-NC group (transfection with NC siRNA), si-KIFC1 group (transfection with KIFC1 siRNA), miR-105+vector group (miR-105 mimics and pcDNA 3.1 co-transfection) and miR-105+KIFC1 group (miR-105 mimics and pcDNA 3.1-KIFC1 co-transfection). The cell proliferation was measured by MTT assay and colony formation assay. The migration and invasion abilities were detected by Transwell methods. The relative luciferase acitivity was evaluated by double luciferase reporter assay. RESULTS:Compared with the adjacent tissues, the expression of miR-105 was significantly decreased and the expression of KIFC1 was significantly increased in NSCLC tissues (P<0.05). Compared with human normal embryonic lung fibroblasts MRC-5, the expression of miR-105 in the H460 cells was significantly decreased, and the expression of KIFC1 was significantly increased (P<0.05). miR-105 inhibited the relative luciferase activity of H460 cells with wild-type KIFC1 and negatively regulated the protein expression of KIFC1. Over-expression of miR-105 and knockdown of KIFC1 expression significantly inhibited the proliferation, migration and invasion abilities of H460 cells. Over-expression of KIFC1 reversed the inhibitory effect of miR-105 on the cell proliferation, migration and invasion abilities of H460 cells. CONCLUSION:miR-105 inhibits the proliferation, migration and invasion abilities of NSCLC cells. The mechanism may be related to targeting and negatively regulating expression of KIFC1.     

miR-193 regulates proliferation of rat marrow mesenchymal stem cells by cell cycle-related proteins

AIM: To investigate the effects of microRNA-193 (miR-193) on the proliferation and apoptosis of rat bone marrow mesenchymal stem cells (MSCs). METHODS: Cultured rat MSCs were transfected with pre-miR-193 or anti-miR-193 to regulate the expression of miR-193. The proliferation of the MSCs after transfection was evaluated by MTS assay, colorimetric BrdU cell proliferation assay and Ki-67 immunostaining. Cell apoptosis was analyzed by flow cytometry with Annexin V/PI staining. The effect of miR-193 on the expression of cell cycle-related proteins was evaluated by qRT-PCR. RESULTS: Transfection of pre-miR-193 or anti-miR-193 regulated the expression of miR-193 in MSCs effectively. Over-expression of miR-193 significantly promoted the proliferation of MSCs (P<0.05), and inhibition of miR-193 reduced the proliferation of MSCs (P<0.05). miR-193 had no significant effect on the apoptosis of MSCs (P>0.05). The result of qRT-PCR indicated miR-193 promoted the expression of cyclin-dependent kinase 2 (CDK2) significantly (P<0.01). CONCLUSION: miR-193 promotes the proliferation of MSCs possibly through the CDK2 pathway.     

Effects of bradykinin on proliferation of porcine pulmonary artery smooth muscle cells induced by TGF-β1

AIM: To investigate the effects of bradykinin (BK) on the proliferation of pulmonary artery smooth muscle cells (PASMCs) induced by transforming growth factor beta 1 (TGF-β1) and its possible mechanisms. METHODS: Primary porcine PASMCs were isolated, cultured and identified, and the cells at passages 2~6 were used in this study. The viability of PASMCs was determined by Cell Counting Kit-8 assay. The protein expression of phosphatidylinositol 3-kinase (PI3K), phosphorylated Akt (p-Akt) and phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) was detected by Western blotting. RESULTS: TGF-β1 promoted the proliferation of PASMCs in a dose-dependent manner (P<005). BK significantly inhibited the proliferation of PASMCs induced by TGF-β1 (P<005), and attenuated the elevated expression of PI3K, p-Akt and p-ERK1/2 proteins (P<005). HOE-140, a BK type 2 receptor (B2R) inhibitor, reversed the effects of BK (P<005). CONCLUSION: BK inhibits TGF-β1-induced proliferation of PASMCs, which may be associated with inactivation of PI3K/Akt and ERK1/2 signaling pathways.     

lncRNA-MALAT1 targets and downregulates miR-570-3p expression to promote proliferation of gastric cancer cells

AIM:To investigate whether long non-coding RNA MALAT1 (lncRNA-MALAT1) targets and down-regulates microRNA-570-3p (miR-570-3p) expression to further promote the proliferation of gastric cancer cells. METHODS:Gastric cancer cell line SGC7901 was cultured in vitro and divided into 3 groups:blank control, si-MALAT1 and si-MALAT1 NC. The si-MALAT1 and si-MALAT1 NC groups were transfected with MALAT1 siRNA and its negative control, respectively. The cell proliferation was evaluated by MTS assay. The expression of miR-570-3p was detected at different time points in the pure SGC7901 gastric cancer cell line, and the expression of lncRNA-MALAT1 and miR-570-3p in different groups was detected by RT-qPCR. The potential complementary binding sites of lncRNA-MALAT1 and miR-570-3p were predicted by RegRNA. The MALAT1 gene and its mutant fragment were cloned into luciferase reporter vector psiCHECK-2. Restriction enzyme analysis and sequencing were used to identify whether the recombinant plasmids carrying MALAT1 or MALAT1-Mut were successfully constructed. miR-570-3p mimic, miR-570-3p inhibitor, miR-570-3p mimic negative control and miR-570-3p inhibitor negative control were co-transfected into the 293T cells with the luciferase repor-ters containing MALAT1 or MALAT1-Mut. Dual-luciferase reporter assay was performed to detect luciferase activity in different groups in order to verify the relationship between lncRNA-MALAT1 and miR-570-3p. RESULTS:Compared with blank control group and si-MALAT1 NC group, the A₄₉₀ value in si-MALAT1 group was significantly decreased (P<0.01). The expression of miR-570-3p presented an obvious declining trend over time. The expression of lncRNA-MALAT1 in si-MALAT1 group was remarkably decreased, whereas the expression of miR-570-3p was obviously increased. The dual-luciferase reporter assay indicated that the MALAT1 reporter luciferase activity decreased significantly in miR-570-3p mimic group compared with mimic negative control (P<0.01), and the luciferase activity of MALAT1 reporter was obviously up-regulated in miR-570-3p inhibitor group compared with miR-570-3p mimic group (P<0.01). However, miR-570-3p mi-mic, miR-570-3p inhibitor, miR-570-3p mimic negative control and miR-570-3p inhibitor negative control showed no effect on the luciferase activity of MALAT1-Mut reporter. CONCLUSION:lncRNA-MALAT1 targets and down-regulates miR-570-3p expression to further promote the proliferation of gastric cancer cells.