Microglia are important cells involved in the regulation of neuropathic pain (NPP) and morphine tolerance. Information on their plasticity and polarity has been elucidated after determining their physiological structure, but there is still much to learn about the role of this type of cell in NPP and morphine tolerance. Microglia mediate multiple functions in health and disease by controlling damage in the central nervous system (CNS) and endogenous immune responses to disease. Microglial activation can result in altered opioid system activity, and NPP is characterized by resistance to morphine. Here we investigate the regulatory mechanisms of microglia and review the potential of microglial inhibitors for modulating NPP and morphine tolerance. Targeted inhibition of glial activation is a clinically promising approach to the treatment of NPP and the prevention of morphine tolerance. Finally, we suggest directions for future research on microglial inhibitors.
Humans ; Calcitonin Gene-Related Peptide/antagonists & inhibitors* ; Drug Tolerance ; Hypoglycemic Agents/pharmacology* ; Microglia/physiology* ; MicroRNAs/physiology* ; Minocycline/pharmacology* ; Morphine/pharmacology* ; Neuralgia/etiology* ; Plant Extracts/pharmacology* ; Signal Transduction/physiology*

OBJECTIVE: To investigate the effect of sodium valproate (VPA) on activation of miR-34c-5p/ATG4B signaling pathway and autophagy in SH-SY5Y cells. METHODS: Routinely cultured SH-SY5Y cells were treated with VPA at different doses for 24 h, and the changes in the mRNA levels of ATG4B and miR-34c-5p and the protein expression of ATG4B were assessed using qRTPCR and immunoblotting, respectively. The effect of transfection with a plasmid containing ATG4B promoter on the promoter activity of ATG4B in VPA-treated SH-SY5Y cells was assessed using the reporter gene assay. The stability of ATG4B mRNA was analyzed with qPCR in SH-SY5Y cells treated with VPA alone or with VPA combined with the transcription inhibitor actinomycin D. The expression level of miR-34c-5p was detected using qPCR in SH-SY5Y cells treated with VPA alone or with VPA combined with miR-34c-5p mimics or antagonist, and the role of miR-34c-5p in VPA-induced ATG4B down-regulation was evaluated. The changes in the level of autophagy were evaluated by detecting LC3-Ⅱ expression in the cells after treatment with VPA or VPA combined with miR-34c-5p antagonist. RESULTS: VPA dose-dependently down-regulated the expression of ATG4B at both the mRNA and protein levels in SH-SY5Y cells. VPA treatment did not significantly affect the promoter activity of ATG4B, but obviously lowered the mRNA stability of ATG4B in SH-SY5Y cells. VPA treatment up-regulated the expression of miR-34c-5p, and the miR-34c-5p antagonist reversed VPA-induced down-regulation of ATG4B in SH-SY5Y cells. VPA also down-regulated the expression level of LC3-Ⅱ in SH-SY5Y cells. CONCLUSIONS VPA suppresses autophagy in SH-SY5Y cells possibly via activating miR-34c-5p/ATG4B signaling pathway.
Autophagy ; drug effects ; Autophagy-Related Proteins ; genetics ; metabolism ; Cell Line ; Cysteine Endopeptidases ; genetics ; metabolism ; Dactinomycin ; pharmacology ; Down-Regulation ; Genes, Reporter ; Humans ; MicroRNAs ; antagonists & inhibitors ; metabolism ; Microtubule-Associated Proteins ; metabolism ; RNA, Messenger ; metabolism ; Signal Transduction ; drug effects ; Transfection ; Valproic Acid ; administration & dosage ; antagonists & inhibitors ; pharmacology

OBJECTIVE: To investigate the expression profile of miR-122-5p in melanoma tissues and the effect of miR-122-5p on the proliferation, cell cycle and apoptosis of human melanoma cell lines SK-MEL-110 and A375. METHODS: The expression profiles of miR-122-5p in melanoma and pigmented nevus tissues were detected using real-time fluorescence quantitative PCR (qRT-PCR). SK-MEL-110 and A375 cells transfected with miR-122-5p inhibitor or negative control inhibitor (NC) I were examined for miR-122- 5p expression using qRT-PCR and changes in cell proliferation, cell cycle and apoptosis using MTT assay or flow cytometry. NOP14 mRNA and protein expressions in the cells were detected using qRT- PCR and Western blotting, respectively. Luciferase reporter assay was used to confirm the identity of NOP14 as the direct target of miR-122-5p. RESULTS: The relative expression of miR-122-5p in human pigmented nevus tissues and melanoma tissues was 1.23±0.270 and 7.65 ± 1.37, respectively. The relative expression of miR-122-5p in SK-MEL-110 and A375 cells transfected with miR-122-5p inhibitor was 0.21 ± 0.08 and 0.17 ± 0.05, respectively. miR-122-5p inhibitor obviously inhibited the cell proliferation and increased the percentage of cells in G1 stage in both SK-MEL-110 and A-375 cells, but did not cause obvious changes in the apoptosis of the two cells. miR-122-5p inhibitor did not significantly affect the expression level of NOP14 mRNA, but obviously increased the expression level of NOP14 protein. Luciferase reporter assay revealed a significantly lower luciferase activity in cells co-transfected with miR-122-5p mimics and wild-type psi-CHECK2-3'UTR plasmid than in the cells cotransfected with NC and wild-type psi-CHECK2-3'UTR plasmid (0.21 ± 0.14 0.56 ± 0.1, < 0.01). CONCLUSIONS miR-122-5p expression is upregulated in melanoma tissues, indicating its involvement in the development of melanoma. miR-122-5p inhibits the proliferation of SK-MEL-110 and A-375 cells possibly by affecting the cycle through NOP14.
Apoptosis ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Luciferases ; metabolism ; Melanoma ; etiology ; metabolism ; pathology ; MicroRNAs ; antagonists & inhibitors ; metabolism ; Neoplasm Proteins ; metabolism ; Nevus, Pigmented ; etiology ; metabolism ; pathology ; Nuclear Proteins ; metabolism ; Skin Neoplasms ; etiology ; metabolism ; pathology ; Up-Regulation

OBJECTIVETo study the effect of a microRNA-132 antagonist on lithium-pilocarpine-induced status epilepticus (SE) in young Sprague-Dawley (SD) rats.

METHODSForty-five 3-week-old SD rats were randomly and equally divided into epilepticus model group, microRNA-132 antagonist group, and microRNA-132 antagonist negative control group. The young SD rat model of SE was established using lithium-pilocarpine. For the microRNA-132 antagonist group and the negative control group, pretreatment was performed 24 hours before the model establishment. Behavioral observation was performed to assess the latency of SE and success rate of induction of SE. The scale of Lado was used to evaluate the seizure severity. Electroencephalography (EEG) was used to assess the frequency and amplitude of epileptiform discharges. The mortality rate was calculated in each group.

RESULTSThere was no significant difference in the success rate of induction of SE between the three groups (P>0.05). Compared with the microRNA-132 negative control group and the epilepticus model group, the microRNA-132 antagonist group had significantly prolonged SE latency after model establishment (P<0.05), a significantly lower Lado score of seizure (P<0.05), significantly lower frequency and amplitude of epileptiform discharges on EEG (P<0.05), and a slightly reduced mortality rate.

CONCLUSIONSThe treatment with the microRNA-132 antagonist shows an inhibitory effect on the development and progression of lithium-pilocarpine-induced SE in young SD rats. The inhibition of microRNA-132 is likely to be a potential target or direction for drug treatment of SE.

Animals ; Electroencephalography ; Male ; MicroRNAs ; antagonists & inhibitors ; Pilocarpine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Status Epilepticus ; chemically induced ; drug therapy

To investigate the function and regulation mechanism of ATP-binding cassette, subfamily G, member 2 (ABCG2) in retinoblastoma cancer stem cells (RCSCs), a long-term culture of RCSCs from WERI-Rb1 cell line was successfully established based on the high expression level of ABCG2 on the surface of RCSCs. To further explore the molecular mechanism of ABCG2 on RCSCs, a microRNA that specifically targets ABCG2 was predicted. Subsequently, miR-3163 was selected and confirmed as the ABCG2-regulating microRNA. Overexpression of miR-3163 led to a significant decrease in ABCG2 expression. Additionally, ABCG2 loss-of-function induced anti-proliferation and apoptosis-promoting functions in RCSCs, and multidrug resistance to cisplatin, carboplatin, vincristine, doxorubicin, and etoposide was greatly improved in these cells. Our data suggest that miR-3163 has a significant impact on ABCG2 expression and can influence proliferation, apoptosis, and drug resistance in RCSCs. This work may provide new therapeutic targets for retinoblastoma.
3' Untranslated Regions ; ATP Binding Cassette Transporter, Sub-Family G, Member 2/antagonists & inhibitors/genetics/*metabolism ; Antagomirs/metabolism ; Antineoplastic Agents/toxicity ; Apoptosis/drug effects ; Base Sequence ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Drug Resistance, Neoplasm/drug effects ; Gene Silencing ; Humans ; MicroRNAs/antagonists & inhibitors/genetics/*metabolism ; Neoplasm Proteins/antagonists & inhibitors/genetics/*metabolism ; Neoplastic Stem Cells/*metabolism ; Retinoblastoma/metabolism/pathology ; Sequence Alignment ; Transfection

Osteosarcoma is the most common primary sarcoma of bone, and it is a leading cause of cancer death among adolescents and young adults. However, the molecular mechanism underlying osteosarcoma carcinogenesis remains poorly understood. Recently, cyclin-dependent kinase 6 (CDK6) was identified as an important oncogene. We found that CDK6 protein level, rather than CDK6 mRNA level, is much higher in osteosarcoma tissues than in normal adjacent tissues, which indicates a post-transcriptional mechanism involved in CDK6 regulation in osteosarcoma. MiRNAs are small non-coding RNAs that repress gene expression at the post-transcriptional level and have widely been shown to play important roles in many human cancers. In this study, we investigated the role of miR-29b as a novel regulator of CDK6 using bioinformatics methods. We demonstrated that CDK6 can be downregulated by miR-29b via binding to the 3'-UTR region in osteosarcoma cells. Furthermore, we identified an inverse correlation between miR-29b and CDK6 protein levels in osteosarcoma tissues. Finally, we examined the function of miR-29b-driven repression of CDK6 expression in osteosarcoma cells. The results revealed that miR-29b acts as a tumor suppressor of osteosarcoma by targeting CDK6 in the proliferation and migration processes. Taken together, our results highlight an important role for miR-29b in the regulation of CDK6 in osteosarcoma and may open new avenues for future osteosarcoma therapies.
3' Untranslated Regions ; Animals ; Base Sequence ; Bone Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cyclin-Dependent Kinase 6 ; antagonists & inhibitors ; genetics ; metabolism ; Humans ; Mice ; MicroRNAs ; metabolism ; Osteosarcoma ; metabolism ; pathology ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; metabolism ; Rats ; Sequence Alignment ; Up-Regulation

3' Untranslated Regions ; Animals ; Antagomirs ; metabolism ; Base Sequence ; Binding Sites ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Humans ; Mice ; MicroRNAs ; antagonists & inhibitors ; genetics ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; metabolism ; Rats ; Sequence Alignment ; Snail Family Transcription Factors ; antagonists & inhibitors ; genetics ; metabolism ; Stomach Neoplasms ; genetics ; pathology

OBJECTIVETo investigate the role of miR-181c in glycolysis of cancer-associated fibroblasts (CAFs) and explore the mechanism.

METHODSHuman lung CAFs and normal fibroblasts (NFs), isolated from fresh human lung adenocarcinoma tissue specimens by primary culture of tissue explants, were transfected with a miR -181c mimics, a miR-181c inhibitor, a siRNA siRNA-HK2 or the vector HK2-vector via Lipofectamine(TM) 2000. Quantitative real-time PCR was used to analyze the changes in miR-125b expression in the transfected cells; hexokinase-2 (HK2) protein expression in the cells was detected using Western blotting, and the cellular glucose uptake was assessed with 2-NBDG. Lactate production in the cells was examined and expression of HK2 mRNA was detected with dual luciferase reporter gene assay.

RESULTSNo obvious difference was found in the cell morphology between CAFs and NFs. Compared with the NFs, the CAFs showed obviously increased glucose uptake, lactate production and HK2 protein expression with decreased expressions of the miR-181 family (P<0.05). Transfection with the miR-181 inhibito- rsignificantly increased glucose uptake, lactate production and HK2 protein expression in the NFs. In CAFs, transfection with the miR-181 mimics caused significantly lowered glucose uptake, lactate production and HK2 protein expression of. Knockdown of endogenous HK2 by siRNA abolished miR-181 mimics-mediated decrease of glucose uptake and lactate production in CAFs, while transfection with miR-181 mimics suppressed HK2 overexpression-induced enhancement of glucose uptake and lactate production in NFs.

CONCLUSIONTransfection with miR-181 mimics can suppress glycolysis in CAFs by inhibiting HK2 expression.

4-Chloro-7-nitrobenzofurazan ; analogs & derivatives ; Adenocarcinoma ; pathology ; Deoxyglucose ; analogs & derivatives ; Fibroblasts ; drug effects ; Glycolysis ; Hexokinase ; antagonists & inhibitors ; Humans ; Lung Neoplasms ; pathology ; MicroRNAs ; pharmacology ; RNA, Messenger ; RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; Transfection ; Tumor Cells, Cultured

OBJECTIVETo investigate the effect of anti-miR-145 on human airway smooth muscle cell (HASMC) proliferation and osteopontin systhesis in vitro and explore the mechanisms.

METHODSHASMCs were treated with 10-100 nmol/L anti-miR-145, and the cell proliferation and apoptosis were investigated using a CCK-8 assay and flow cytometry, respectively. The changes in osteopontin synthesis after the treatment was quantified with Western blotting.

RESULTSTreatment with 10 and 50 nmol/L anti-miR-145 significantly promoted the proliferation and osteopontin synthesis in HASMCs (P<0.05 or <0.01), and 50 nmol/L anti-miR-145 obviously inhibited the cell apoptosis (P<0.01).

CONCLUSIONAnti-miR-145 promotes HASMC proliferation and osteopontin synthesis and inhibits HASMC apoptosis in vitro, indicating the important role of anti-miR-145 in the pathogenesis of airway remodeling.

Airway Remodeling ; Apoptosis ; Cell Proliferation ; Cells, Cultured ; Humans ; MicroRNAs ; antagonists & inhibitors ; Myocytes, Smooth Muscle ; drug effects ; Osteopontin ; biosynthesis ; Respiratory System ; cytology

Although methyltransferase has been recognized as a major element that governs the epigenetic regulation of the genome during temozolomide (TMZ) chemotherapy in glioblastoma multiforme (GBM) patients, its regulatory effect on glioblastoma chemoresistance has not been well defined. This study investigated whether DNA methyltransferase (DNMT) expression was associated with TMZ sensitivity in glioma cells and elucidated the underlying mechanism. DNMT expression was analyzed by western blotting. miR-20a promoter methylation was evaluated by methylation-specific PCR. Cell viability and apoptosis were assessed using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and TdT-mediated dUTP-biotin nick end labeling assays, respectively. The results showed that compared with parental U251 cells, DNMT1 expression was downregulated, miR-20a promoter methylation was attenuated and miR-20a levels were elevated in TMZ-resistant U251 cells. Methyltransferase inhibition by 5-aza-2\'-deoxycytidine treatment reduced TMZ sensitivity in U251 cells. In U251/TM cells, DNMT1 expression was negatively correlated with miR-20a expression and positively correlated with TMZ sensitivity and leucine-rich repeats and immunoglobulin-like domains 1 expression; these effects were reversed by changes in miR-20a expression. DNMT1 overexpression induced an increase in U251/TM cell apoptosis that was inhibited by the miR-20a mimic, whereas DNMT1 silencing attenuated U251/TM cell apoptosis in a manner that was abrogated by miR-20a inhibitor treatment. Tumor growth of the U251/TM xenograft was inhibited by pcDNA-DNMT1 pretreatment and boosted by DNMT1-small hairpin RNA pretreatment. In summary, DNMT1 mediated chemosensitivity by reducing methylation of the microRNA-20a promoter in glioma cells.
Animals ; Antineoplastic Agents, Alkylating/*pharmacology/therapeutic use ; Apoptosis/drug effects ; Brain/drug effects/metabolism/pathology ; Brain Neoplasms/drug therapy/*genetics/pathology ; DNA (Cytosine-5-)-Methyltransferase/antagonists & inhibitors/*genetics/metabolism ; DNA Methylation ; Dacarbazine/*analogs & derivatives/pharmacology/therapeutic use ; Drug Resistance, Neoplasm ; Female ; Gene Expression Regulation, Neoplastic ; Glioma/drug therapy/*genetics/pathology ; Humans ; Mice, Inbred C57BL ; MicroRNAs/*genetics ; Promoter Regions, Genetic