ABSTRACT
Objective To investigate the effects of microRNA-134 (miR-134) on the proliferation and apoptosis of non-small cell lung cancer (NSCLC) and its potential molecular mechanism.Methods Quantitative real-time fluorescent polymerase chain reaction (qRT-PCR) was used to detect the differences of miR-134 expression between 10 cases of lung cancer tissues and normal lung tissues,and between normal human lung epithelial cell line BEAS-2B and lung adenocarcinoma cell line A549.miR-NC and miR-134 mimic were transfected into A549 cells.The effect of miR-134 on proliferation of A549 cells was detected by methyl thiazolyl tetrazolium (MTT) and colony form experiment.Flow cytometry was used to determine the effect of miR-134 on A549 cells apoptosis.The effect of miR-134 on the expression of P53 protein was detected by Western blotting.Results The relative expressions of miR-134 in NSCLC tumor tissues and adjacent tissues were 0.429 ± 0.126 and 0.971 ±0.183 respectively,and the difference was statistically significant (t =7.742,P ＜0.001).The relative expressions of miR-134 in BEAS-2B cells and A549 cells were 1.013 ± 0.095 and 0.371 ± 0.068 respectively,and the difference was statistically significant (t =17.377,P ＜ 0.001).The absorbance (A) values of A549 cells transfected with miR-mimic were 0.451 ±0.051 and 0.518 ±0.074 on the third and forth day respectively,and those of A549 cells transfected with miR-NC were 0.683 ± 0.041 and 0.815 ± 0.065 respectively.The proliferation ability of miR-mimic group was significantly lower than that of miR-NC group (t =12.965,P ＜ 0.001;t =9.535,P ＜ 0.001).The colony forming rates of A549 cells transfected with miR-NC and miR-134 mimic were 91.2％ ± 8.3％ and 38.6％ ±4.5％ respectively,and the colony forming rate of A549 cells in miR-134 mimic group was significantly decreased (t =17.617,P ＜0.001).The apoptosis rates of miR-134 mimic group and miR-NC group were 93.5％ ± 3.7％ and 85.4％ ± 2.0％ respectively,and the difference was significant difference (t =6.119,P ＜ 0.001).The relative expressions of P53 protein in miR-134 mimic group and miR-NC group were 1.816 ±0.173 and 0.992 ± 0.096 respectively,and the difference was statistically significant (t =19.308,P ＜ 0.001).Conclusion miR-134 can be an effective target for the treatment of NSCLC by increasing the protein expression of P53,inhibiting the viability and proliferation of tumor cells,and promoting the apoptosis of tumor cells.
ABSTRACT
Objective: To To investigate the changes of MicroRNA-134, CREB and p-CREB expression in epileptic rat brains in order to elucidate the molecular mechanisms of epilepsy, providing new ideas for clinical treatment. Methods: Sixty-four Spraque-Dawley (SD) rats were divided into groups randomly, including control group, six hours after seizure group, 24-hour group, three-day group, one-week group, two-week group, four-week group, and eight-week group. All groups were placed under a pilocarpine-induced epilepsy model except the control group, and all rats were decapitated in different points of time. Brain specimens were taken for quantitative PCR experiments, immunohistochemistry and Western blot experiments. The results of the epilepsy model groups and the control group were compared. Results: There were no significant differences between the six hours after seizure group, the 24-hour group and the control group about the MicroRNA-134 levels. MicroRNA-134 in the hippocampus tissue of the three-day group significantly reduced compared with the control group; same result was observed with the one-week, two-week, four-week and eight-week groups. The CREB and p-CREB levels in the three-day group's rat hippocampus significantly increased compared with the control group; and the high levels of CREB and p-CREB were constantly maintained in the one-week, two-week, four-week and eight-week groups. Conclusions: The MicroRNA-134 level of the epileptic rat hippocampus is significantly lower than normal after three days, and continues to maintain a low level; while CREB and p-CREB levels are rsignificantly increased after three days, and continue to remain at a high level. MicroRNA-134 plays a role in inhibiting synaptic plasticity by inhibiting CREB and p-CREB expressions.
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OBJECTIVE@#To To investigate the changes of MicroRNA-134, CREB and p-CREB expression in epileptic rat brains in order to elucidate the molecular mechanisms of epilepsy, providing new ideas for clinical treatment.@*METHODS@#Sixty-four Spraque-Dawley (SD) rats were divided into groups randomly, including control group, six hours after seizure group, 24-hour group, three-day group, one-week group, two-week group, four-week group, and eight-week group. All groups were placed under a pilocarpine-induced epilepsy model except the control group, and all rats were decapitated in different points of time. Brain specimens were taken for quantitative PCR experiments, immunohistochemistry and Western blot experiments. The results of the epilepsy model groups and the control group were compared.@*RESULTS@#There were no significant differences between the six hours after seizure group, the 24-hour group and the control group about the MicroRNA-134 levels. MicroRNA-134 in the hippocampus tissue of the three-day group significantly reduced compared with the control group; same result was observed with the one-week, two-week, four-week and eight-week groups. The CREB and p-CREB levels in the three-day group's rat hippocampus significantly increased compared with the control group; and the high levels of CREB and p-CREB were constantly maintained in the one-week, two-week, four-week and eight-week groups.@*CONCLUSIONS@#The MicroRNA-134 level of the epileptic rat hippocampus is significantly lower than normal after three days, and continues to maintain a low level; while CREB and p-CREB levels are rsignificantly increased after three days, and continue to remain at a high level. MicroRNA-134 plays a role in inhibiting synaptic plasticity by inhibiting CREB and p-CREB expressions.
ABSTRACT
Objective: To To investigate the changes of MicroRNA-134, CREB and p-CREB expression in epileptic rat brains in order to elucidate the molecular mechanisms of epilepsy, providing new ideas for clinical treatment. Methods: Sixty-four Spraque-Dawley (SD) rats were divided into groups randomly, including control group, six hours after seizure group, 24-hour group, three-day group, one-week group, two-week group, four-week group, and eight-week group. All groups were placed under a pilocarpine-induced epilepsy model except the control group, and all rats were decapitated in different points of time. Brain specimens were taken for quantitative PCR experiments, immunohistochemistry and Western blot experiments. The results of the epilepsy model groups and the control group were compared. Results: There were no significant differences between the six hours after seizure group, the 24-hour group and the control group about the MicroRNA-134 levels. MicroRNA-134 in the hippocampus tissue of the three-day group significantly reduced compared with the control group; same result was observed with the one-week, two-week, four-week and eight-week groups. The CREB and p-CREB levels in the three-day group’s rat hippocampus significantly increased compared with the control group; and the high levels of CREB and p-CREB were constantly maintained in the one-week, two-week, four-week and eight-week groups. Conclusions: The MicroRNA-134 level of the epileptic rat hippocampus is significantly lower than normal after three days, and continues to maintain a low level; while CREB and p-CREB levels are rsignificantly increased after three days, and continue to remain at a high level. MicroRNA-134 plays a role in inhibiting synaptic plasticity by inhibiting CREB and p-CREB expressions.
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AIM:To investigate the roles of microRNA-134 (miR-134) in the cisplatin resistance of lung ade-nocarcinoma cells.METHODS:miRNA microarray was applied to compare the miRNA expression profile between A549/CDDP and A549 cells.Real-time PCR was used to confirm the expression of miR-134.miR-134 mimics and inhibitors were transfected into A549/CDDP and A549 cells, respectively.MTT assay was used to detect the sensitivity of lung cancer cells to cisplatin.Western blot was applied to test whether miR-134 regulated forkhead box protein M1 ( FOXM1 ) and multi-drug-associated protein 1 ( MRP1 ) expression.RESULTS: Based on the data of miRNA microarray, 13 miRNAs were found to be differentially expressed in A549/CDDP cells compared with A549 cells, among which miR-134 was the most significantly down-regulated one.Compared with control group, A549/CDDP cells transfected with miR-134 mimics showed greatly enhanced sensitivity to cisplatin as indicated by IC50 values (P<0.01).In contrast, suppression of the miR-134 level in the A549 cells resulted in a decreased sensitivity to cisplatin (P<0.01).FOXM1 siRNA down-regulated the pro-tein levels of FOXM1.A549/CDDP cells transfected with si-FOXM1 showed enhanced sensitivity to cisplatin (P<0.01). In addition, the result of Western blot showed that miR-134 repressed MRP1 protein expression.CONCLUSION: miR-134 effectively increases the sensitivity of lung adenocarcinoma cells to cisplatin, and this effect of miR-134 may be partly due to its regulation of FOXM1 and MRP1 expression.
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ObjectiveTo investigate the effects of sleep deprivation on expressions of Mir-132,mir-134 in the different regions of rat brain.MethodsAll the male SD rats were divided into control group ( normal sleep group),sleep deprivation (SD).The modified multiple platform method (MMPM) was used to establish sleep deprivation model.Mir-132,mir-134 level was detected by real time PCR.ResultsMir-132 were significantly increased in SD groups in hippocampus compared with the control groups ( 51.87 ± 8.13 vs 67.25 ± 7.59 ) (P ＜0.01 ).Mir-134 were significantly decreased in SD groups compared with the control groups( 1.82 ±0.15 vs 1.45± 0.12 )(P ＜ 0.01 ).There were no statistically significant differences in cortex and thalamus (P ＞ 0.05 ).Cortex mir-132 level in SD group and control group was 1.57 ±0.10,1.48 ±0.11 respectively,and it was 1.37 ±0.09,1.36 ±0.11 in thalamus;Cortex mir-134 level in SD group and control group was 98.26 ± 5.17,100.80 ±4.15respectively,and it was 97.56 ± 6.28,91.01 ± 4.07 in thalamus.ConclusionThe upregulation of mir-132 and downregulation of mir-134 implies that two miRNAs did opposite actions in the processes of sleep deprivation.This findings indicate that hippocampus mir-132,mir-134 levels in the SD rat may reflect associated depressive patho-physiological processes.