OBJECTIVE: To assess the impacts of electroacupuncture (EA) on the gait, oxidative stress, inflammatory reaction, and protein degradation in the rats of denervated skeletal muscle atrophy, and explore the potential mechanism of EA for alleviating denervated skeletal muscle atrophy. METHODS: Forty male SD rats, 8 weeks old, were randomly assigned to a sham-surgery group, a model group, an EA group, and a p38 MAPK inhibitor group, with 10 rats in each group. The right sciatic nerve was transected to establish a rat model of denervated skeletal muscle atrophy in the model group, the EA group and the p38 MAPK inhibitor group. In the sham-surgery group, the nerve was exposed without transection. One day after successful modeling, the rats in the EA group received EA at "Huantiao" (GB30) and "Zusanli" (ST36) on the right side, using a continuous wave with a frequency of 2 Hz and current intensity of 1 mA, for 15 min in each session, EA was delivered once a day, 6 times a week. In the p38 MAPK inhibitor group, the rats received the intraperitoneal injection with SB203580 (5 mg/kg), once a day, 6 times a week. The intervention was composed of 3 weeks in each group. After the intervention completion, the CatWalk XT 10.6 animal gait analysis system was used to record the gait parameters of rats. The wet weight ratio of the gastrocnemius muscle was calculated after the sample collected. Using HE staining, the fiber morphology and cross-sectional area of the gastrocnemius muscle were observed; ELISA was employed to measure the content of interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α in the gastrocnemius muscle; the biochemical hydroxyamine method was adopted to detect the content of superoxide dismutase (SOD) and malondialdehyde (MDA) in the gastrocnemius muscle; with immunohistochemistry and Western blot used, the expression of p38 mitogen-activated protein kinase (p38 MAPK), phosphorylated (p)-p38 MAPK, muscle atrophy F-box gene (Atrogin-1), muscle RING finger 1 (Murf-1), nuclear factor E2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) was detected in the gastrocnemius muscle. RESULTS: Compared to the sham-surgery group, in the model group, the standing duration, the swing time and the step cycle were increased (P<0.001), the footprint area of the maximum contact time, the print area, the average intensity of the maximum contact time, the average intensity, the swing speed, and the step length were decreased (P<0.001); the wet weight ratio of gastrocnemius muscle and fiber cross-sectional area were reduced (P<0.001); the content of IL-6, IL-1β, TNF-α and MDA in gastrocnemius muscle elevated (P<0.001), and that of SOD reduced (P<0.001); the positive and protein expression of p-p38 MAPK, Atrogin-1 and Murf-1 elevated (P<0.001) and that of Nrf2 and HO-1 dropped (P<0.001). When compared with the model group, in the EA group and the p38 MAPK inhibitor group, the standing duration, the swing time and the step cycle decreased (P<0.01), the footprint area of the maximum contact time, the print area, the average intensity of the maximum contact time, the average intensity, the swing speed, and the step length increased (P<0.01); the wet weight ratio of gastrocnemius muscle and fiber cross-sectional area were improved (P<0.01, P<0.05); the content of IL-6, IL-1β, TNF-α and MDA in gastrocnemius muscle dropped (P<0.05, P<0.01), and that of SOD elevated (P<0.01, P<0.05); the positive and protein expression of p-p38 MAPK, Atrogin-1 and Murf-1 dropped (P<0.01, P<0.05) and that of Nrf2 and HO-1 increased (P<0.01, P<0.05). CONCLUSION Electroacupuncture may alleviate skeletal muscle atrophy in denervated skeletal muscle atrophy rats by mediating the p38 MAPK activity, thereby suppressing oxidative stress, inflammatory reaction, and protein degradation.
Animals ; Electroacupuncture ; Male ; Rats ; p38 Mitogen-Activated Protein Kinases/genetics* ; Rats, Sprague-Dawley ; Muscular Atrophy/metabolism* ; Muscle, Skeletal/metabolism* ; Humans ; Signal Transduction ; Superoxide Dismutase/genetics* ; Tumor Necrosis Factor-alpha/genetics* ; Oxidative Stress ; MAP Kinase Signaling System ; Acupuncture Points

BACKGROUND: Arsenic trioxide (ATO) is indicated as a broad-spectrum medicine for a variety of diseases, including cancer and cardiac disease. While the role of ATO in hepatic ischemia/reperfusion injury (HIRI) has not been reported. Thus, the purpose of this study was to identify the effects of ATO on HIRI. METHODS: In the present study, we established a 70% hepatic warm I/R injury and partial hepatectomy (30% resection) animal models in vivo and hepatocytes anoxia/reoxygenation (A/R) models in vitro with ATO pretreatment and further assessed liver function by histopathologic changes, enzyme-linked immunosorbent assay, cell counting kit-8, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Small interfering RNA (siRNA) for extracellular signal-regulated kinase (ERK) 1/2 was transfected to evaluate the role of ERK1/2 pathway during HIRI, followed by ATO pretreatment. The dynamic process of autophagic flux and numbers of autophagosomes were detected by green fluorescent protein-monomeric red fluorescent protein-LC3 (GFP-mRFP-LC3) staining and transmission electron microscopy. RESULTS: A low dose of ATO (0.75 μmol/L in vitro and 1 mg/kg in vivo ) significantly reduced tissue necrosis, inflammatory infiltration, and hepatocyte apoptosis during the process of hepatic I/R. Meanwhile, ATO obviously promoted the ability of cell proliferation and liver regeneration. Mechanistically, in vitro  studies have shown that nontoxic concentrations of ATO can activate both ERK and phosphoinositide 3-kinase-serine/threonine kinase (PI3K-AKT) pathways and further induce autophagy. The hepatoprotective mechanism of ATO, at least in part, relies on the effects of ATO on the activation of autophagy, which is ERK-dependent. CONCLUSION Low, non-toxic doses of ATO can activate ERK/PI3K-AKT pathways and induce ERK-dependent autophagy in hepatocytes, protecting liver against I/R injury and accelerating hepatocyte regeneration after partial hepatectomy.
Animals ; Arsenic Trioxide ; Autophagy/physiology* ; Reperfusion Injury/prevention & control* ; Mice ; Male ; Proto-Oncogene Proteins c-akt/physiology* ; Arsenicals/therapeutic use* ; Oxides/therapeutic use* ; Liver/metabolism* ; Extracellular Signal-Regulated MAP Kinases/metabolism* ; Mice, Inbred C57BL

This study aimed to investigate the effect and mechanism of Buyang Huanwu Decoction in regulating endoplasmic reticulum stress via the inositol-requiring enzyme 1α(IRE1α)/apoptosis signal-regulating kinase 1(ASK1)/c-Jun N-terminal kinase(JNK) pathway to improve neurological function in rats with cerebral ischemia/reperfusion injury(CIRI). SPF-grade male sprague-dawley(SD) rats were randomly divided into Sham group, model group, Buyang Huanwu Decoction group, and edaravone group. Except for the Sham group, the other groups were subjected to the modified suture method to establish a middle cerebral artery occlusion/reperfusion(MCAO/R) model. After treatment, neurological function was assessed using the Zea Longa scoring system. Gait analysis was used to detect the motor function. Detection of relative infarct area in brain tissue using 2,3,5-triphenyltetrazolium chloride(TTC) staining. Nissl staining was used to observe the structure of neuronal cells. Western blot and real-time fluorescence quantitative PCR(RT-qPCR) were used to detect IRE1α, ASK1, JNK, B cell lymphoma-2(Bcl-2), Bcl-2 related X protein(Bax), and Caspase-3 in the brain tissue. Immunohistochemistry was used to detect the positive expression of IRE1α, ASK1, and JNK. Immunofluorescence was used to detect the fluorescence expression levels of Bax, Bcl-2, and Caspase-3. The results showed that compared with the Sham group, the model group exhibited increased neurological scores(P<0.01), increased ratio of ground contact area and strength in both forelimbs(P<0.01), enlarged relative infarct area of brain tissue(P<0.05), and a reduced number of Nissl staining-positive cells(P<0.01). The protein and mRNA expression levels of IRE1α, ASK1, JNK, Bax, and Caspase-3 in brain tissue were significantly elevated, while those of Bcl-2 were decreased(P<0.05). Compared with the model group, both the Buyang Huanwu Decoction group and edaravone group showed reduced neurological scores(P<0.05), decreased ratio of ground contact area and strength in both forelimbs(P<0.05), smaller relative infarct area(P<0.05), alleviated neuronal damage, and increased number of Nissl staining-positive cells(P<0.05). The expression levels of IRE1α, ASK1, JNK, Bax, and Caspase-3 protein and mRNA in brain tissue were significantly reduced, while those of Bcl-2 were significantly increased(P<0.05). The results indicated that Buyang Huanwu Decoction can effectively improve brain injury in CIRI rats, and its mechanism of action may be related to regulating the endoplasmic reticulum stress IRE1α/ASK1/JNK signaling pathway.
Animals ; Male ; Rats, Sprague-Dawley ; Protein Serine-Threonine Kinases/genetics* ; Drugs, Chinese Herbal/administration & dosage* ; Rats ; MAP Kinase Kinase Kinase 5/genetics* ; Ischemic Stroke/physiopathology* ; Humans ; MAP Kinase Signaling System/drug effects* ; Apoptosis/drug effects* ; Endoribonucleases/genetics* ; JNK Mitogen-Activated Protein Kinases/genetics* ; Endoplasmic Reticulum Stress/drug effects* ; Multienzyme Complexes

This study aims to explore the effects and potential mechanisms of Modified Shuyu Pills in ameliorating depressive behaviors in the mouse model of vascular dementia(VaD). Seventy-two three-month-old male C57BL/6 mice were assigned into six groups: sham, model, low-, medium-, and high-dose Modified Shuyu Pills, and fluoxetine. The other five groups except the sham group underwent bilateral common carotid artery stenosis combined with chronic unpredictable stress. Depressive behaviors were assessed by the sucrose preference test and tail suspension test. Cerebral blood flow was measured by laser speckle imaging. Protein levels of low density lipoprotein receptor(LDLR), mitogen-activated protein kinase kinase(MEK), phosphorylated(p)-MEK, extracellular signal-regulated kinase(ERK), and p-ERK in the ventral tegmental area(VTA) and nucleus accumbens(NAc) were determined by Western blot. The fluorescence intensity of myelin basic protein(MBP) in the VTA and NAc were measured by immunofluorescence. Myelin sheath morphology in the VTA and NAc was observed by luxol fast blue staining, and the ultrastructure of myelin sheath in the VTA and NAc was examined by transmission electron microscopy. In the tail suspension test, the immobility time of the model group was longer than that of the sham group(P<0.01). In the sucrose preference test, the sucrose preference rate of the model group was lower than that of the sham group(P<0.01). After intervention with Modified Shuyu Pills, the immobility time in the tail suspension test was shortened(P<0.01), and the sucrose preference rate increased(P<0.01). Laser speckle imaging results showed that compared with the sham group, the model group showed reduced cerebral blood flow(P<0.01), and the reduction was reversed by medium-and high-dose Modified Shuyu Pills(P<0.01). Western blot results indicated that the relative expression levels of LDLR, p-MEK/MEK, and p-ERK/ERK in the VTA and NAc of the model group were lower than those in the sham group(P<0.01). Medium-and high-dose Modified Shuyu Pills reversed this trend(P<0.01). Immunofluorescence results showed that the fluorescence intensity of MBP in the VTA and NAc of the model group was lower than that of the sham group(P<0.01). The medium-and high-dose Modified Shuyu Pills groups showed increased fluorescence intensity of MBP in the VTA compared with the model group(P<0.01). In the NAc, the fluorescence intensity of MBP in all the groups of Modified Shuyu Pills increased to varying degrees compared with that in the model group(P<0.01). Luxol fast blue staining results showed that the model group presented lighter staining intensity and looser arrangement of myelin fibers than the sham group, indicating significant demyelination in the model group. However, after intervention with medium-and high-dose Modified Shuyu Pills, the staining intensity and myelin sheath structure in the VTA and NAc were improved. Transmission electron microscopy results revealed that the myelin sheath in the VTA and NAc of the sham group was intact and dense, while the model group exhibited extensive myelin loss, with myelin sheath degeneration and disintegration. After intervention with Modified Shuyu Pills, the myelin sheath loss in the VTA and NAc of mice was reduced, and the proportion of myelinated tissue increased. In summary, Modified Shuyu Pills may promote myelination via the VTA-NAc circuit by upregulating the LDLR/MEK/ERK signaling pathway, thereby ameliorating depressive-like behaviors in VaD mice.
Animals ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Mice ; Ventral Tegmental Area/metabolism* ; Mice, Inbred C57BL ; Disease Models, Animal ; Depression/genetics* ; Receptors, LDL/genetics* ; Dementia, Vascular/psychology* ; MAP Kinase Signaling System/drug effects* ; Nucleus Accumbens/metabolism* ; Behavior, Animal/drug effects* ; Humans ; Myelin Sheath/drug effects* ; Extracellular Signal-Regulated MAP Kinases/genetics*

OBJECTIVE: To explore mechanisms of acid-sensing ion channel 1 (ASIC1) mediated lumbar nucleus pulposus cell apoptosis through extracellular-signalregulated protein kinase 5 (ERK5) signaling pathway and mitochondrial dysfunction pathway. METHODS: Totally 34 patients with degenerative lumbar disc herniation (LDH) admitted from January 2020 to December 2022 were collected as research objects, including 21 males and 13 females;aged from 29 to 52 years old with an average of (37.43±4.75) years old;22 patients with grade Ⅱ and 12 patients with grade Ⅳ, according to Pfirrmann grading criteria;15 patients with L_4,5 and 19 patients with L₅S₁. The expression of ASIC1 in nucleus pulposus of LDH patients was measured by immunohistochemical staining. Nucleus pulposus cells were cultured by primary culture method, identified by toluidine blue staining and immunohistochemical staining, and the expression of ASIC1 protein was located by immunofluorescence staining. According to the addition of siRNA-ASIC1, ASIC1 overexpression plasmid, and ERK5 inhibitors, the nucleus pulpocyte was divided into three groups, named as SIRNA-silenced group, overexpression group, and inhibitor group, with 3 patients in each group. Cells of each group were collected at 72 h after intervention, expression of ASIC1, ERK5, BCL-xL/BCL-2-associated Death promoter (Bad), B-cell lymphoma-2 associated X (Bax) and B-cell lymphoblast-2 gene (Bcl-2) were detected by reverse transcription-polymerase chain reaction (RT-PCR);intracellular calcium ion levels were detected by calcium ion kit, mitochondrial membrane potential was detected by JC-1 kit, and apoptosis was observed by AV-PI kit. RESULTS: In LDH patients with grade Ⅳ, nucleus pulposus tissue removed during operation revealed poor elasticity, white color and poor ductility, and immunohistochemical results showed increased ASIC1 expression. There was no significant difference in mRNA relative expression of ASIC1 between siRNA silencing group (0.31±0.03) and inhibitor group (0.39±0.05) (P>0.05). The mRNA relative expression level of ERK5 in siRNA silencing group(0.32±0.05) was significantly higher than that in inhibitor group (0.15±0.04)(P<0.05), which suggested ERK5 was the downstream molecule of ASIC1. The mRNA relative expression levels of apoptosis promoting factor Bad and Bax in siRNA silencing group and inhibitor group were lower than those in overexpression group(P<0.05), the relative expression level of anti-apoptosis factor Bcl-2 mRNA was significantly increased (P<0.05). The calcium content in overexpression group was higher than that in siRNA silencing and inhibitor groups (P<0.05), the normal proportion of mitochondrial membrane potential in overexpression group was lower than that in siRNA silencing and inhibitor group (P<0.05), and the apoptosis rate in overexpression group was higher than that in siRNA silencing and inhibitor group (P<0.05). CONCLUSION After the activation of ASIC1 channel protein, calcium ions could enter the cells and act as a second messenger molecule to regulate apoptosis of nucleus pulposus cells by ERK5 signaling pathway and mitochondrial disorder pathway.
Humans ; Acid Sensing Ion Channels/physiology* ; Male ; Female ; Apoptosis ; Middle Aged ; Adult ; Signal Transduction ; Mitogen-Activated Protein Kinase 7/physiology* ; Mitochondrial Diseases/genetics* ; Nucleus Pulposus/metabolism* ; Intervertebral Disc Degeneration/metabolism* ; Mitochondria/metabolism* ; Intervertebral Disc Displacement/genetics*

OBJECTIVE: To analyze the influences of dihydromyricetin on the proliferation and apoptosis of chondrocytes in osteoarthritis induced by hydrogen peroxide (H₂O₂) through reactive oxygen species (ROS)/p38 mitogen activated protein kinase (p38-MAPK) pathway. METHODS: Five C57BL/6J mice were euthanized by cervical dislocation after anesthesia. Chondrocytes were extracted and cultured.After passage, the chondrocytes were divided into control group, H2O2 group (0.8 μmol·L^-1 H₂O₂), dihydromyricetin low concentration group (0.8 μmol·L^-1 H₂O₂+20 μmol·L^-1 dihydromyricetin), dihydromyricetin high concentration group (0.8 μmol·L^-1 H₂O₂+80 μmol·L^-1 dihydromyricetin), and ROS inhibitor N-acetylcysteine (NAC) group (0.8 μmol·L^-1 H₂O₂+5 mmol·L^-1 NAC). The activity of chondrocytes was measured by methyl thiazolyl tetrazolium (MTT) assay. The apoptosis rate of chondrocytes was measured by Hoechst 33342 method. The level of ROS in chondrocytes was measured by 2, 7-dichlorofluorescein diacetate (DCFH-DA) fluorescence probe.The level of Type II collagen α1 (Col2α1) mRNA was measured by qRT-PCR.And the expression of Col2α1, p-p38-MAPK/p38-MAPK, B cell lymphoma gene-2 (Bcl-2) and Bcl-2 associated X protein (Bax) proteins was detected by Western blot. RESULTS: The chondrocytes showed swirling fibrous mass, and the expression of COL2α was positive. Compared with the control group, the chondrocyte viability, apoptosis rate, ROS fluorescence intensity, p-p38-MAPK/p38-MAPK, and the expression of Bax protein in H2O22 group increased, the level of Col2α1 mRNA, and the expression of Col2α1 and Bcl-2 proteins decreased (P<0.05). Compared with H₂O₂ group, the chondrocyte viability, apoptosis rate, ROS fluorescence intensity, p-p38-MAPK/p38-MAPK, and the expression of Bax protein in dihydromyricetin low concentration group, dihydromyricetin high concentration group, and NAC group decreased, the level of Col2α1 mRNA, and the expression of Col2α1 and Bcl-2 proteins increased (P<0.05). CONCLUSION Dihydromyricetin may inhibit chondrocyte apoptosis, inflammatory reaction and oxidative stress by inhibiting ROS/p38-MAPK pathway. Dihydromyricetin may be a potential drug for treating osteoarthritis.
Animals ; Chondrocytes/metabolism* ; Apoptosis/drug effects* ; Hydrogen Peroxide/toxicity* ; Osteoarthritis/physiopathology* ; Mice, Inbred C57BL ; Reactive Oxygen Species/metabolism* ; Mice ; Flavonols/pharmacology* ; p38 Mitogen-Activated Protein Kinases/genetics* ; Cell Proliferation/drug effects* ; Male ; Signal Transduction/drug effects* ; MAP Kinase Signaling System/drug effects* ; Cells, Cultured

Objective The aim of this study was to investigate the effect of p38 on stem cell maintenance of pancreatic cancer. Methods Human pancreatic cancer cells PANC-1 were treated with different concentrations of 5-fluorouracil(5-FU)(0.5×IC₅₀, IC₅₀, and 2×IC₅₀) for 24 hours, and VX-702 (p38 phosphorylation inhibitor) was added, and the cells were inoculated in 6-well culture dishes with ultra-low adhesion to observe the changes of sphere tumors. The expression levels of cyclin-dependent kinase 2(CDK2), cyclin B1 and D1, Octamer-binding transcription factor 4(OCT4), SRY-box transcription factor 2(SOX2), Nanog and p38 were measured by Western blot. The mRNA expression levels of p38, OCT4, Nanog and SOX2 were tested by RT-PCR. Cell cycle, apoptosis, and the proportion of CD44⁺CD133⁺PANC-1 cells were evaluated by flow cytometry. Results The results showed that 5-FU inhibited the formation of tumor spheres in PANC-1 cells, increased CD44⁺CD133⁺cell fragments, down-regulated the expression of OCT4, Nanog and SOX2, and inhibited the stemness maintenance of PANC-1 tumor stem cells. Phosphorylation of PANC-1 cells was inhibited by a highly selective p38 MAPK inhibitor, VX-702(p38 mitogen-activated protein kinase inhibitor), which had the same effect as 5-FU treatment. When VX-702 combined with 5-FU was used to treat PANC-1 cells, the therapeutic effect was enhanced. Conclusion p38 inhibitors decreased PANC-1 cell activity and increased cell apoptosis. p38 inhibitors inhibit the stemness maintenance of pancreatic cancer stem cells.
Humans ; Phosphorylation/drug effects* ; Cell Line, Tumor ; p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors* ; Neoplastic Stem Cells/metabolism* ; Drug Resistance, Neoplasm/drug effects* ; Fluorouracil/pharmacology* ; Pancreatic Neoplasms/pathology* ; Apoptosis/drug effects* ; SOXB1 Transcription Factors/genetics* ; Octamer Transcription Factor-3/genetics*

OBJECTIVES: To investigate the effect of interferon-λ1 (IFN-λ1) on glucocorticoid (GC) resistance in human bronchial epithelial cells (HBECs) stimulated by respiratory syncytial virus (RSV). METHODS: HBECs were divided into five groups: control, dexamethasone, IFN-λ1, RSV, and RSV+IFN-λ1. CCK-8 assay was used to measure the effect of different concentrations of IFN-λ1 on the viability of HBECs, and the sensitivity of HBECs to dexamethasone was measured in each group. Quantitative real-time PCR was used to measure the mRNA expression levels of p38 mitogen-activated protein kinase (p38 MAPK), glucocorticoid receptor (GR), and MAPK phosphatase-1 (MKP-1). Western blot was used to measure the protein expression level of GR in cell nucleus and cytoplasm, and the nuclear/cytoplasmic ratio of GR was calculated. RESULTS: At 24 and 72 hours, the proliferation activity of HBECs increased with the increase in IFN-λ1 concentration in a dose- and time-dependent manner (P˂0.05). Compared with the RSV group, the RSV+IFN-λ1 group had significant reductions in the half-maximal inhibitory concentration of dexamethasone and the mRNA expression level of p38 MAPK (P<0.05), as well as significant increases in the mRNA expression levels of GR and MKP-1, the level of GR in cell nucleus and cytoplasm, and the nuclear/cytoplasmic GR ratio (P<0.05). CONCLUSIONS IFN-λ1 can inhibit the p38 MAPK pathway by upregulating MKP-1, promote the nuclear translocation of GR, and thus ameliorate GC resistance in HBECs.
Humans ; p38 Mitogen-Activated Protein Kinases/genetics* ; Glucocorticoids/pharmacology* ; Receptors, Glucocorticoid/analysis* ; Dual Specificity Phosphatase 1/physiology* ; Dexamethasone/pharmacology* ; Drug Resistance/drug effects* ; Respiratory Syncytial Viruses ; Interferons/pharmacology* ; MAP Kinase Signaling System/drug effects* ; Epithelial Cells/drug effects* ; Signal Transduction/drug effects* ; Cells, Cultured

BACKGROUND: Double-stranded RNA-specific adenosine deaminase 1 (ADAR1) binds to double-stranded RNA and catalyzes the deamination of adenosine (A) to inosine (I). The functional mechanism of ADAR1 in non-small cell lung cancer (NSCLC) remains incompletely understood. This study aimed to investigate the prognostic significance of ADAR1 in NSCLC and to elucidate its potential role in regulating tumor cell proliferation and migration. METHODS: Data from The Cancer Genome Atlas (TCGA) and cBioPortal were analyzed to assess the correlation between high ADAR1 expression and clinicopathological features as well as prognosis in lung cancer. We performed Western blot (WB), cell proliferation assays, Transwell invasion/migration assays, and nude mouse xenograft modeling to examine the phenotypic changes and molecular mechanisms induced by ADAR1 knockdown. Furthermore, the ADAR1 p150 overexpression model was utilized to validate the proposed mechanism. RESULTS: ADAR1 expression was significantly elevated in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) tissues compared with adjacent non-tumor tissues (LUAD: P=3.70×10-15, LUSC: P=0.016). High ADAR1 expression was associated with poor prognosis (LUAD: P=2.03×10-2, LUSC: P=2.81×10-2) and distant metastasis (P=0.003). Gene Set Enrichment Analysis (GSEA) indicated that elevated ADAR1 was associated with mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway activation, matrix metalloproteinase-9 (MMP-9) expression, and cell adhesion. ADAR1 and MMP-9 levels showed a strongly positive correlation (P=6.45×10-34) in 10 lung cancer cell lines, highest in H1581. Knockdown of ADAR1 in H1581 cells induced a rounded cellular morphology with reduced pseudopodia. Concomitantly, it suppressed cell proliferation, invasion, migration, and in vivo tumorigenesis. It also suppressed ERK phosphorylation and downregulated cellular Finkel-Biskis-Jinkins murine osteosarcoma viral oncogene homolog (c-FOS), MMP-9, N-cadherin, and Vimentin. Conversely, ADAR1 p150 overexpression in PC9 cells enhanced ERK phosphorylation and increased c-FOS and MMP-9 expression. CONCLUSIONS High ADAR1 expression is closely associated with poor prognosis and distant metastasis in NSCLC patients. Mechanistically, ADAR1 may promote proliferation, invasion, migration, and tumorigenesis in lung cancer cells via the ERK/c-FOS/MMP-9 axis.
Humans ; Lung Neoplasms/physiopathology* ; Adenosine Deaminase/genetics* ; Matrix Metalloproteinase 9/genetics* ; Cell Proliferation ; Carcinoma, Non-Small-Cell Lung/physiopathology* ; Cell Movement ; Animals ; Mice ; RNA-Binding Proteins/genetics* ; Female ; Male ; Cell Line, Tumor ; Proto-Oncogene Proteins c-fos/genetics* ; Middle Aged ; MAP Kinase Signaling System ; Gene Expression Regulation, Neoplastic ; Mice, Nude ; Extracellular Signal-Regulated MAP Kinases/genetics*

OBJECTIVE: To examine the mechanism of action of tanshinone II A (Tan II A) in promoting chemosensitization of osteosarcoma cells to cisplatin (DDP). METHODS: The effects of different concentrations of Tan II A (0-80 µ mol/L) and DDP (0-2 µ mol/L) on the proliferation of osteosarcoma cell lines (U2R, U2OS, 143B, and HOS) at different times were examined using the cell counting kit-8 and colony formation assays. Migration and invasion of U2R and U2OS cells were detected after 24 h treatment with 30 µ mol/L Tan II A, 0.5 µ mol/L DDP alone, and a combination of 10 µ mol/L Tan II A and 0.25 µ mol/L DDP using the transwell assay. After 48 h of treatment of U2R and U2OS cells with predetermined concentrations of each group of drugs, the cell cycle was analyzed using a cell cycle detection kit and flow cytometry. After 48 h treatment, apoptosis of U2R and U2OS cells was detected using annexin V-FITC apoptosis detection kit and flow cytometry. U2R cells were inoculated into the unilateral axilla of nude mice and then the mice were randomly divided into 4 groups of 6 nude mice each. The 4 groups were treated with equal volume of Tan II A (15 mg/kg), DDP (3 mg/kg), Tan II A (7.5 mg/kg) + DDP (1.5 mg/kg), and normal saline, respectively. The body weight of the nude mice was weighed, and the tumor volume and weight were measured. Cell-related gene and signaling pathway expression were detected by RNA sequencing and Kyoto Encyclopedia of Genes and Genomes pathway analysis. p38 MAPK signaling pathway proteins and apoptotic protein expressions were detected by Western blot. RESULTS: In vitro studies have shown that Tan II A, DDP and the combination of Tan II A and DDP inhibit the proliferation, migration and invasion of osteosarcoma cells. The inhibitory effect was more pronounced in the Tan II A and DDP combined treatment group (P<0.05 or P<0.01). Osteosarcoma cells underwent significantly cell-cycle arrest and cell apoptosis by Tan II A-DDP combination treatment (P<0.05 or P<0.01). In vivo studies demonstrated that the Tan II A-DD combination treatment group significantly inhibited tumor growth compared to the Tan II A and DDP single drug group (P<0.01). Additionally, we found that the combination of Tan II A and DDP treatment enhanced the p38 MAPK signaling pathway. Western blot assays showed higher p-p38, cleaved caspase-3, and Bax and lower caspase-3, and Bcl-2 expressions with the combination of Tan II A and DDP treatment compared to the single drug treatment (P<0.01). CONCLUSION Tan II A synergizes with DDP by activating the p38/MAPK pathway to upregulate cleaved caspase-3 and Bax pro-apoptotic gene expressions, and downregulate caspase-3 and Bcl-2 inhibitory apoptotic gene expressions, thereby enhancing the chemosensitivity of osteosarcoma cells to DDP.
Abietanes/therapeutic use* ; Osteosarcoma/enzymology* ; Cisplatin/therapeutic use* ; Humans ; Cell Line, Tumor ; Animals ; Apoptosis/drug effects* ; Mice, Nude ; Cell Proliferation/drug effects* ; Cell Movement/drug effects* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; MAP Kinase Signaling System/drug effects* ; Bone Neoplasms/enzymology* ; Cell Cycle/drug effects* ; Xenograft Model Antitumor Assays ; Mice ; Drug Resistance, Neoplasm/drug effects* ; Neoplasm Invasiveness ; Mice, Inbred BALB C