Molecular mechanism of miR-1246 enhancing radiosensitivity of cervical cancer cells

AIM: To investigate the molecular mechanism of microRNA-1246(miR-1246) enhancing radiosensitivity of cervical cancer cells. METHODS: Cervical cancer lines HeLa, CaSki, C33A and SiHa were transfected with miR-1246 mimic and negative control mimic (NC-mimic) using Lipofectamine 2000 kit, and the expression level of miR-1246 in cervical cancer tissue, normal tissue, cervical cancer cell lines and endometrial epithelium cell line ESC was detected by real-time PCR. The transfected cells were exposed to X-ray radiation. The cell viability and migration rate were measured respectively by MTT assay and Transwell method. The protein levels of γH2AX, ATM, p-ATM and p-p53 were monitored by immunofluorescence and Western blot. RESUITS: Higher miR-1246 level was found in normal tissue and ESC cells, while lower miR-1246 level was found in HeLa, SiHa, C33A and Caski cells and cervical cancer tissues. The expression level of miR-1246 in the cells transfected with miR-1246 mimic was significantly higher than that in the cells transfected with NC-mimic (P<0.05). The cell viability and migration rate of the cervical cancer cells with miR-1246 over-expression were notably lower than those of the cells transfected with NC-mimic (P<0.05) under the same conditions. The results of immunofluorescence indicated that the protein expression level of γH2AX significantly increased in the cervical cancer cells with miR-1246 over-expression exposed to radiation compared with the negative control (P<0.05). The protein expression level of γH2AX was significantly increased in the cervical cancer cells with miR-1246 over-expression, while the protein levels of p-ATM and p-p53 were significantly decreased as compared with the negative control group (P<0.05). CONCLUSION: miR-1246 is highly expressed in normal tissue and normal endometrial epithelial cells, while is low expressed in the cervical cancer tissues or cells. miR-1246 over-expression inhibits growth and migration, and significantly enhances radiosensitivity of cervical cancer cells. The molecular mechanism is possibly related to inhibiting ATM pathway and DNA damage repair.     

Changes of miR-155-5p in serum of cervical cancer patients and effects of miR-155-5p on cervical cancer cells

AIM:To detect the serum level of miR-155-5p in the patients with different cervical diseases, and to analyze its effects on the proliferation, cell cycle and apoptosis of cervical cancer cells. METHODS:SYBR Green I real-time quantitative PCR was used to detect the level of miR-155-5p in the serum of the patients with different cervical diseases. miR-155-5p mimic or inhibitor was used to increase or decrease the expression of miR-155-5p in cervical cancer cells. The proliferation, cell cycle and apoptosis were measured by CCK-8 assay and flow cytometry. RESULTS:The serum level of miR-155-5p in cervical cancer group was higher than that in cervicitis group and healthy group. No statistical difference of the serum miR-155-5p level between cervical intraepithelial neoplasia group and cervical cancer group was observed. Compared with blank group, liposome group and negative control group, the proportion of S-phase cells increased and apoptotic cells decreased in SiHa cells transfected with 100 nmol/L and 200 nmol/L miR-155-5p mimic. The proportion of G2/M-phase cells increased significantly in SiHa cells transfected with 100 nmol/L and 200 nmol/L miR-155-5p inhibitor. CONCLUSION: Compared with healthy controls, the serum level of miR-155-5p in the cervical cancer patients increases, and may act as a novel tumor molecular marker for diagnosis of cervical cancer. miR-155-5p has no significant effect on the proliferation, cell cycle and apoptosis of HeLa cell. miR-155-5p may promote SiHa cells to enter S phase and inhibit the apoptosis of SiHa cells.     

Mechanism of miR-30c over-expression inhibiting malignant phenotypes of cervical cancer cells

AIM:To investigate the molecule mechanism of microRNA (miR)-30c over-expression inhibiting malignant phenotypes of cervical cancer cells. METHODS:Cervical cancer cell lines C33A, HeLa, SiHa and CaSki were transfected with pGenesil-1-miR-30c plasmid using Lipofectamine 2000 kit, and the expression of miR-30c was determined by TaqMan real-time PCR. The cell viability inhibition rate, colony formation ability, migration rate and apoptotic rate were measured by MTT assay, colony formation assay, Transwell experiment, and flow cytometry with Annexin V-FITC staining. The protein expression of Bax, Bcl-2, matrix metalloproteinase (MMP)-9, MMP-13 and tissue inhibitor of metalloprotei-nase-1 (TIMP-1) was detected by Western blot. RESULTS:The expression levels of miRNA-30c in the cervical cancer cell lines transfected with pGenesil-1-miR-30c plasmid were significantly higher than those in negative control groups (cell lines transfected with pGenesil-1 plasmid) (P<0.01). Significantly increased cell viability inhibition rate, and decreased colony formation ability and migration rate were found in the cervical cancer cell lines over-expressing miR-30c as compared with negative control groups (P<0.05). The apoptotic rate in the cervical cancer cell lines over-expressing miR-30c was dramatically higher than that in control groups (P<0.05). Over-expression of miR-30c in cervical cancer cells promoted the protein expression of Bax and TIMP-1, and decreased the protein expression of Bcl-2 and MMP-13 (P<0.05 or P<0.01). CONCLUSION:Over-expression of miR-30c significantly inhibits the viability and migration, and induces apoptosis of cervical cancer cells. The mechanism may be related to activating apoptosis pathway and inhibiting MMP-13 protein expression.     

miR-125a-5p reverses cisplatin resistance of non-small-cell lung cancer A549/DDP cells by targeting LIMK1

AIM:To explore the effect of microRNA-125a-5p (miR-125a-5p) on cisplatin (DDP) resistance of non-small-cell lung cancer A549/DDP cells and its related mechanisms. METHODS:The expression levels of miR-125a-5p and LIM kinase 1 (LIMK1) in non-small-cell lung cancer tissues, A549 cells and A549/DDP cells were detected by RT-qPCR. The A549/DDP cell viability, apoptotic rate and expression of drug resistance-related proteins after over-expression or knockdown of miR-125a-5p and/or LIMK1 expression were detected by MTT assay, flow cytometry and Western blot, respectively. The targeting relationship between miR-125a-5p and LIMK1 was verified by TargetScan online prediction and dual-luciferase reporter system. The cell viability, apoptotic rate and expression of drug resistance-related proteins after co-expression of miR-125a-5p and LIMK1 were also determined. RESULTS:The expression level of miR-125a-5p was down-regulated and LIMK1 expression was up-regulated in non-small-cell lung cancer tissues and cell lines (P<0.05). The results of dual-luciferase assay indicated that miR-125a-5p negatively regulated the expression of LIMK1. The expression of drug resistance-related proteins and the viability of A549/DDP cells were inhibited after over-expression of miR-125a-5p or knockdown of LIMK1, while the apoptosis was enhanced. Over-expression of LIMK1 attenuated the inhibitory effect of miR-125a-5p on A549/DDP cell viability and drug resistance-related protein expression (P<0.05). CONCLUSION:miR-125a-5p reverses the resistance of A549/DDP cells to DDP by inhibiting the expression of LIMK1 and drug resistance-related proteins.     

Expression and significance of miR-193b in cervical cancer

AIM: To investigate the expression of microRNA-193b(miR-193b) in the cervical tissues, and further to explore the effect of silencing miR-193b on diamminedichloroplatinum(DDP)-treated HeLa cell viability. METHODS: The expression levels of miR-193b in different cervical tissues were examined by qPCR. After transfection of miR-193b-inhibitor, the cell migration was determined by Transwell assay, the sensitivity of HeLa cells to DDP was measured by MTT assay, the protein levels of phosphate and tension homology deleted on chromsome ten(PTEN), protein kinase B(Akt), p-Akt and p-glycoprotein(P-gp) were determined by Western blot. RESULTS: The mRNA level of miR-193b was significantly increased in the cervical cancer tissues compared with normal cervical tissues(P<0.05). Knockdown of miR-193b obviously inhibited migration and enhanced sensitivity to DDP of HeLa cells(P<0.05). Additionally, after transfection of miR-193b-inhibitor, the expression of PTEN was increased, whereas the protein levels of p-Akt and P-gp were decreased(P<0.05). CONCLUSION: miR-193b is highly expressed in the cervical cancer tissues. Inhibition of miR-193b augments the sensitivity to DDP of HeLa cells, at least in part, through PTEN-PI3K/Akt signaling pathway.     

Molecular mechanism of miR-29a inhibiting malignant phenotypes in prostate cancer cells

AIM:To investigate the biological functions of microRNA-29a (miR-29a) in prostate cancer and the molecular mechanism of miR-29a over-expression inhibiting malignant phenotypes of prostate cancer cells. METHODS:The levels of miR-29a expression in the prostate cancer tissues and cells were detected and analyzed using gene microarray and bioinformatics. The expression levels of miR-29a and lysine (K)-specific demethylase 4B (KDM4B) mRNA in prostate cancer tissues, paracarcinomatous tissues, 4 prostate cancer cell lines (PC3, DU145, LNCaP and ArCaP) and normal prostate epithelial cell line (RWPE-1) were measured by real-time PCR. PC3, DU145, LNCaP and ArCaP cells were transfected with pGenesil-1-miR-29a plasmid using transient transfection. The cell viability, colony formation rate and apoptotic rate were analyzed by MTT assay, colony formation assay and flow cytometry with Annexin V-FITC/PI staining, respectively. The protein expression of KDM4B was determined by Western blot. RESULTS:The results of gene microarray and bioinformatic analysis indicated that differential expression of miR-29a was found in the prostate cancer tissues and the paracarcinomatous tissues. The levels of miR-29a in the prostate cancer tissues and prostate cancer cells were significantly decreased, while the mRNA levels of KDM4B were notably increased compared with the paracarcinomatous tissues and RWPE-1 cells, respectively (P<0.05). Compared with negative control (pGenesil-1) group, the cell viability and colony formation rate were significantly decreased, the apoptotic rate was significantly increased, and the protein expression of KDM4B was notably inhibited in the prostate cancer cells with miR-29a over-expression (P<0.05). The cell viability was significantly enhanced, and the apoptosis was significantly inhibited in the prostate cancer cells with KDM4B over-expression (P<0.05). CONCLUSION:Low expression of miR-29a was found in the prostate cancer tissues and cells. miR-29a over-expression inhibits the growth of prostate cancer cells and induces apoptosis. The mechanism may be associated with inhibiting the protein expression of KDM4B.     

Pulsatilla saponin A affects proliferation and radiosensitivity of breast cancer cells by regulating miR-24-3p/RNF2 expression

AIMTo investigate the effect of Pulsatilla saponin A on proliferation and radiosensitivity of breast cancer cells and its mechanism. METHODSHuman breast cancer MCF-7 cells were treated with Pulsatilla saponin A at concentrations of 0, 5, 10, 15 and 20 mg/L and transfected with microRNA-24-3p (miR-24-3p) over-expression vector or inhibitory expression vector. The proliferation and radiosensitivity of the MCF-7 cells were measured by MTT assay and colony formation assay. The miR-24-3p expression and ring finger protein 2 （RNF2） mRNA level were detected by RT-qPCR. The protein expression of RNF2 was determined by Western blot. The luciferase reporter assay was used to detect the targeting relationship between miR-24-3p and RNF2. RESULTSCompared with control group (0 mg/L), the proliferation inhibitory rate of the MCF-7 cells was significantly increased in 5, 10, 15 and 20 mg/L Pulsatilla saponin A groups (P<0.05). The survival score of the MCF-7 cells treated with Pulsatilla saponin A was significantly decreased after irradiation, and the expression of RNF2 was significantly decreased (P<0.05). miR-24-3p targeted RNF2 and negatively regulated its expression. When the MCF-7 cells were simultaneously treated with Pulsatilla saponin A and miR-24-3p, the cell survival curve significantly shifted down. Inhibition of miR-24-3p expression reversed the proliferation-inhibiting and radiation-sensitizing effects of Pulsatilla saponin A on the MCF-7 cells. CONCLUSION Pulsatilla saponin A may affect the proliferation and radiosensitivity of breast cancer cells through miR-24-3p/RNF2 signaling pathway.     

Clinical significance of STMN1 expression in cervical cancer and effect of inhibition of its expression on viability and apoptosis of cervical cancer SiHa cells

AIM: To investigate the clinical significance of stathmin 1 (STMN1) expression in cervical cancer and the influence of its expression on the viability and apoptosis of cervical cancer cells. METHODS: Western blot was used to detect the protein expression of STMN1 in cervical cancer tissues, and the relationship between the expression and clinical characteristics of cervical cancer was analyzed. STMN1-siRNA was transfected into cervical squamous-cell carcinoma SiHa cells. The protein levels of STMN1, STAT3, p-STAT3 and survivin were determined by Western blot after transfection for 48 h. The cell viability was measured by MTT assay. The apoptosis was analyzed by flow cytometry. DCFH-DA probe was used to detect the level of reactive oxygen species (ROS). RESULTS: The protein expression of STMN1 in cervical cancer tissues was significantly higher than that in paracancerous tissues (P<0.01). The STMN1 protein expression level was not correlated with age and histological types of cervical cancer patients, but was related to clinical stage, histological differentiation and lymph node metastasis (P<0.01). Transfection with STMN1-siRNA significantly reduced the expression of STMN1 in SiHa cells. Compared with control group, the cell viability in STMN1-siRNA group was significantly decreased, the apoptotic rate and ROS content were increased, and the protein levels of p-STAT3 and survivin were down-regulated (P<0.01). However, no significant difference of the STAT3 protein level was observed between STMN1-siRNA group and control group. CONCLUSION: STMN1 is highly expressed in cervical cancer, and its expression is related to clinical stage, histological differentiation and lymph node metastasis. Inhibition of STMN1 expression reduces the viability and promotes apoptosis of cancer cells by down-regulating STAT3 signaling pathway.     

miR-24-3p targeting KLF6 gene affects viability and apoptosis of esophageal cancer cells via IL-6/STAT3 signaling pathway

AIM: To investigate the effect of microRNA-24-3p (miR-24-3p) on the viability and apoptosis of esophageal cancer cells. METHODS: The expression of miR-24-3p and KLF6 mRNA in the esophageal cancer cells TE11, Eca109 and EC9706 were detected by RT-qPCR. The protein expression of KLF6 was determined by Western blot. EC9706 cells were transfected with anti-miR-24-3p and KLF6 siRNA. The cell viability was measured by MTT assay, the apoptotic rate was analyzed by flow cytometry, and the proliferation, apoptosis and IL-6/STAT3 signaling pathways related proteins were determined by Western blot. The level of IL-6 was measured by ELISA. The dual luciferase reporter gene assay was used to verify the relationship between miR-24-3p and KLF6. RESULTS: The levels of miR-24-3p were up-regulated in the esophageal cancer cells TE11, Eca109 and EC9706 (P < 0.05), and the expression of KLF6 at mRNA and protein levels was down-regulated (P < 0.05). Knock-down of miR-24-3p expression inhibited the cell viability, induced apoptosis, and inhibited the protein levels of CDK4, cyclin D1, CDC25A, p-STAT3, Bcl-2 and IL-6, and promoted the protein expression of caspase-3 and Bax in EC9706 cells. CONCLUSION: miR-24-3p targets KLF6 gene to affect the viability and apoptosis of esophageal cancer cells by regulating IL-6/STAT3 signaling pathway.     

MicroRNA-126 enhances radiosensitivity of SGC-7901 cells via targeting inhibition of EZH2

AIM: To investigate the molecular biological mechanisms by which microRNA-126 (miR-126) enhances the radiosensitivity of gastric cancer cells. METHODS: SGC-7901 cells were cultured in vitro. In order to over-express miR-126 in SGC-7901 cells, miR-126 mimic was transfected. The mRNA and protein levels of enhancer of zeste ho-molog 2 (EZH2) were detected by RT-qPCR and Western blot, respectively. The targeting relationship between miR-126 and EZH2 was determined by dual-luciferase reporter assay. To estimate the effect of EZH2 on miR-126-enhanced radiosensitivity of the SGC-7901 cells, the pcDNA3.1-EZH2 vector was also co-transfected with miR-126 mimic, and then CCK-8 assay and flow cytometry were used to detect the viability and apoptotic rate of the cells after radiation. RESULTS: Over-expression of miR-126 significantly inhibited the expression of EZH2 in SGC-7901 cells both at protein and mRNA levels (P<0.05). A direct targeting relationship between miR-126 and EZH2 was confirmed by dual-luciferase reporter assay. Compared with the cells only transfected with miR-126 mimic, co-transfection of pcDNA3.1-EZH2 with miR-126 mimic increased the viability but reduced the apoptosis of the cells treated by radiation (P<0.05). CONCLUSION: Targeting inhibition of EZH2 may be one of the mechanisms by which miR-126 enhances the radiosensitivity of gastric cancer cells.     

MicroRNA-98 suppresses viability and invasion ability of colorectal can-cer cells by targeting EZH2

AIM: To study the target relationship between microRNA-98 (miR-98) and enhancer of Zeste homolog 2 (EZH2), and the effect of miR-98 on the viability and invasion ability of colorectal cancer cells.METHODS: The target relationship between EZH2 and miR-98 was predicted by TargetScan software and confirmed by dual-luciferase reporter assay. The miR-98 mimic and miR-98 inhibitor were transfected into human colorectal cancer SW480 cells and SW620 cells. The protein expression level of EZH2 was determined by Western blot. The cell viability was measured by MTT assay, and the invasion ability was detected by Transwell assay. EZH2 over-expression vector was transfected into the colorectal cancer cells, and the cell viability and invasion ability were measured.RESULTS: miR-98 targeted EZH2 and down-regulated EZH2 protein expression in the SW480 cells and SW620 cells. miR-98 over-expression significantly decreased, while miR-98 knockdown dramatically increased the viability and invasion ability of SW480 cells and SW620 cells. Additionally, EZH2 over-expression enhanced the viability and invasion ability of SW480 cells and SW620 cells.CONCLUSION: miR-98 inhibits the viability and invasion ability of SW480 cells and SW620 cells by targeting EZH2, which may provide new therapeutic target and method for colorectal cancer treatment.     

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.     

Effect of ARMCX1 on proliferation and apoptosis of cervical cancer SiHa cells

AIM: To observe the effect of Armadillo repeat-containing X-linked protein 1 (ARMCX1) on the proliferation and apoptosis of human cervical cancer SiHa cells by knock-down of ARMCX1 expression with small interfering RNA. METHODS: After knock-down of ARMCX1 expression, the cell cycle distribution and apoptosis of SiHa cells were detected by flow cytometry. The proliferation of SiHa cells was observed by plate colony formation assay after knock-down of ARMCX1 for 10 d. The protein levels of cell proliferation-and apoptosis-related molecules were determined by Western blot. RESULTS: After knock-down of ARMCX1 expression in the SiHa cells, the cell colony formation ability was significantly inhibited (P < 0.05), the cell cycle was arrested in S phase, and the protein levels of cyclin E and cell division cycle 25A (Cdc25A) in the SiHa cells were decreased. Meanwhile, knock-down of ARMCX1 expression promoted the apoptosis of SiHa cells, significantly reduced the protein expression of Bcl-2, and significantly increased the protein levels of Bax and active caspase-3 (P < 0.05). CONCLUSION: Knock-down of ARMCX1 expression inhibits the proliferation of SiHa cells and induces apoptosis.     

Down-regulation of miR-153-3p attenuates H2O2-induced H9C2 cell injury by promoting Nrf2 expression

AIM To study the effect of microRNA-153-3p (miR-153-3p) knock-down on oxidative injury of H9C2 cells induced by H₂O₂ and its specific mechanism. METHODS The oxidative stress injury of H9C2 cell model was induced by H₂O₂, and then the cell viability and the expression of miR-153-3p were detected by MTT assay and RT-qPCR, respectively. The effects of miR-153-3p knock-down on the H9C2 cell injury under oxidative stress were studied by RNA interference technology. The targets of miR-153-3p were identified by Western blot and dual-luciferase reporter assay. RESULTS MTT assay showed that the viability of H9C2 cells was decreased with the increase in H₂O₂ concentration (P<0.05). The results of RT-qPCR showed that the expression of miR-153-3p was increased with the increase in H₂O₂ concentration (P<0.05). Knock-down of miR-153-3p increased the viability of H9C2 cells under oxidative stress, decreased the cell apoptosis and the content of malondialdehyde (MDA), and increased the activity of superoxide dismutase (SOD). The expression of nuclear factor E2-related factor 2（Nrf2） and antioxidant response element（ARE） activity were increased with the increase in H₂O₂ concentration (P<0.01). TargetScan analysis and dual-luciferase reporter assay showed that Nrf2 was one of the potential target genes of miR-153-3p. The results of Western blot further showed that over-expression of miR-153-3p inhibited the expression of Nrf2 (P<0.01), while down-regulation of miR-153-3p increased the expression of Nrf2 (P<0.01). Dual interference with Nrf2 and miR-153-3p significantly reduced H9C2 cell viability, promoted the apoptosis, increased MDA content, and decreased SOD activity in the presence of H₂O₂ (P<0.01). CONCLUSION Inhibition of miR-153-3p expression attenuates the injury of H9C2 cells induced by H₂O₂ through up-regulating Nrf2/ARE signaling pathway.     

Effects of pterostilbene on cervical cancer cell autophagy and SIRT1-FoxO signaling pathway

AIM To study the effect of pterostilbene (PTE) on autophagy and SIRT1-FoxO signaling pathway in cervical cancer cells. METHODS Human cervical cancer HeLa cells were used as the study objects. CCK-8 assay and flow cytometry were used to determine the effects of PTE at different concentrations on the viability and apoptotic rate of HeLa cells. The mRNA expression of SIRT1 and FoxO in the cells was detected by qPCR. The number of autophagosomes in the cells was observed under transmission electron microscope.The protein levels of SIRT1, FoxO, LC3-Ⅰ,LC3-Ⅱ, p62, Bax and Bcl-2 in the cells were determined by Western blot. RESULTS After treatment with PTE for 24 and 48 h, the viability inhibitory rate of the HeLa cells was increased with increasing PTE concentration. Compared with 0 μmol/L PTE, after 15, 30 and 60 μmol/L PTE treatment, the apoptotic rate of the HeLa cells, the number of autophagosomes in the cells, and the protein levels of Bax, LC3-Ⅱ/LC3-Ⅰ, SIRT1 and FoxO were increased (P<0.05), while the protein levels of Bcl-2 and p62 were decreased (P<0.05) in a concentration-dependent manner. CONCLUSION PTE may induce autophagy and apoptosis of HeLa cells by activating SIRT1-FoxO signaling pathway, and inhibit HeLa cell viability.     

Effect of miR-23b-3p on viability and apoptosis of rheumatoid arthritis synovial fibroblasts by targeting XIAP

AIM:To investigate the effect of microRNA-23b-3p (miR-23b-3p) on the viability and apoptosis of rheumatoid arthritis synovial fibroblasts by targeting X-linked inhibitor of apoptosis protein (XIAP). METHODS:The expression of miR-23b-3p and XIAP was detected by RT-qPCR. The TargetScan was used to predict the targeting regulatory relation between miR-23b-3p and XIAP, and then the regulatory relation was confirmed by dual-luciferase reporter assay. After the miR-23b-3p mimic and inhibitor were transfected into the cells, the expression of miR-23b-3p and XIAP was detect by RT-qPCR. The effect of miR-23b-3p on the viability and apoptosis was measured by CCK-8 assay and flow cytometry. The protein expression levels of Ki67 and Bcl-2 were determined by Western blot. RESULTS:The expression level of miR-23b-3p was down-regulated significantly (P<0.05), and XIAP was up-regulated significantly in rheumatoid arthritis synovial fibroblasts (P<0.05). The miR-23b-3p mimic significantly inhibited XIAP expression and the cell viability, promoted the apoptosis, and down-regulated the expression of Ki67 and Bcl-2 (P<0.05). The effects of miR-23b-3p inhibitor were the opposite. CONCLUSION:miR-23b-3p inhibits the viability and promotes apoptosis of rheumatoid arthritis synovial fibroblasts by targeting XIAP.     

Role of miR-486-5p in apoptosis of human bone marrow mesenchymal stem cells induced by hydrogen peroxide

AIM: To investigate the role of microRNA-486-5p (miR-486-5p) in the apoptosis of human bone marrow mesenchymal stem cells (hMSCs) induced by hydrogen peroxide (H₂O₂). METHODS: The hMSCs were cultured in vitro and exposed to serum-free medium and H₂O₂ (10 mmol/L). The changes of miR-486-5p expression in oxidative stress-related apoptosis of hMSCs were measured by real-time PCR. The hMSCs were transfected with miR-486-5p mimic or inhibitor at concentration of 30 nmol/L by Lipofectamine RNAiMAX. The effect of miR-486-5p on H₂O₂-induced decrease in cell viability was evaluated by MTT assay. Hoechst 33342 staining and flow cytometry were applied to determine the role of miR-486-5p in the apoptosis of hMSCs. The protein expression was evaluated by Western blotting. Caspase-3 activity was determined using a caspase-3 activity kit. RESULTS: Compared with control group, the expression of miR-486-5p significantly decreased after treated with H₂O₂ (P<0.05). In addition, over-expression of miR-486-5p in the hMSCs reduced the cell viability, accelerated apoptosis, down-regulated Bcl-2/Bax ratio, caspase-3 enzyme precursor content and phosphorylation of Akt, and activated caspase-3 activity. Conversely, down-regulation of miR-486-5p significantly inhibited H₂O₂-induced cell apoptosis and the caspase-3 activity, increased cell viability and up-regulated Bcl-2/Bax ratio and phosphorylation level of Akt. CONCLUSION: Over-expression of miR-486-5p promotes H₂O₂-induced hMSCs apoptosis, and repression of miR-486-5p protects hMSCs from H₂O₂-induced cellular apoptosis, which may be mediated by regulating Akt signaling pathway.     

miR-485-5p inhibits viability and migration and invasion abilities of hepatocellular carcinoma Hep3B cells by targeting SOX5

AIM: To investigate the effects of microRNA-485-5p (miR-485-5p) on the viability, migration and invasion abilities of hepatocellular carcinoma cells and the underlying mechanism. METHODS: The expression levels of sex determining region Y-box 5 (SOX5) mRNA and miR-485-5p in the hepatocellular carcinoma Hep3B cells were detected by RT-qPCR with normal hepatocyte THLE-3 as control. Western blot was used to measure the expression levels of SOX5, proliferating cell nuclear antigen (PCNA), Ki67, cyclin D1 and matrix metalloproteinase-2 (MMP-2). The viability of Hep3B cells was measured by MTT assay. The migration and invasion abilities of the Hep3B cells were detected by Transwell assay. Dual-luciferase reporter assay system was applied to verify the relationship between miR-485-5p and SOX5. RESULTS: Compared with the control cells, the expression level of miR-485-5p was decreased in hepatocellular carcinoma cells Hep3B, Huh7 and HCCLM3 (P<0.05), while the expression of SOX5 at mRNA and protein levels were significantly increased (P<0.05). Over-expression of miR-485-5p inhibited the viability, migration and invasion of Hep3B cells. miR-485-5p targeted the 3′-UTR of SOX5 and negatively regulated the expression of SOX5. Knocking-down of SOX5 expression inhibited the viability, migration and invasion of Hep3B cells. Over-expression of SOX5 partially reversed the inhibitory effect of miR-485-5p over-expression on the viability, migration and invasion of Hep3B cells. CONCLUSION: miR-485-5p inhibits the viability, migration and invasion of Hep3B cells by targeting SOX5 gene. miR-485-5p is a potential molecular target for hepatocellular carcinoma.     

Mechanism of microRNA-138-5p inhibiting proliferation,migration and invasion of lung cancer cells

AIM: To investigate the mechanism of microRNA-138-5p (miR-138-5p) inhibiting the proliferation, migration and invasion abilities of lung cancer cells.METHODS: The lung cancer A549 and H460 cells were transfected with miR-NC (control group) or miR-138-5p (experimental group). The bioinformatic analysis was performed to predict the target genes of miR-138-5p.The expression levels of miR-138-5p, forkhead box protein C1 (FOXC1) mRNA and vimentin mRNA were detected by RT-qPCR. The protein expression of FOXC1, vimentin, E-cadherin, N-cadherin and β-catenin was determined by Western blot. MTS method and colony formation assay were used to detect cell viability and proliferation ability. Wound healing assay and Transwell assay were used to detect cell migration and invasion ability.RESULTS: Over-expression of miR-138-5p significantly reduced the expression of FOXC1 and vimentin at mRNA and protein levels (P<0.05). The expression of E-cadherin and β-catenin were up-regulated and the expression of N-cadherin was down-regulated. The proliferation, migration and invasion abilities of the lung cancer cells were inhibited by the over-expression of miR-138-5p.CONCLUSION: miR-138-5p inhibits the proliferation, migration and invasion abilities of lung cancer cells by targeting FOXC1 and vimentin. It may be a potential target for lung cancer gene therapy.