Yi Qi Jie Du Formula and Salinomycin Combination Treatment Mediates Nasopharyngeal Carcinoma Stem Cell Proliferation,Migration and Apoptosis via CD44/Ras Signaling Pathway

Objective To assess the effects of Yi Qi Jie Du Formula(YQJDF)combined with salinomycin(SAL)on nasopharyngeal carcinoma stem cells(NPC-SCs)and investigate the underlying molecular mechanisms.Methods Cell counting methods,the CCK-8 assay,transwell migration assay and JC-1 staining,were used to observe the effects of the combination on the proliferation,migration and apoptosis of NPC stem cells,respectively.Western blot was used to detect the levels of protein in NPC-SCs.Results YQJDF combined with SAL had a synergistic effect on the inhibition of proliferation and migration and induction of NPCSC apoptosis.Mechanistically,YQJDF combined with SAL synergistically upregulated the levels of apoptotic proteins,including cleaved Caspase-3,cleaved Caspase-7 and cleaved Caspase-9.Moreover,YQJDF combined with SAL synergistically decreased the levels of CD44,p-c-Src,Ras,p-PKCδ,p-MEK,p-c-Raf,p-ERK1/2 and p-AKT proteins.Conclusions The combination of YQJDF and SAL has a synergistic effect on the inhibition of NPC-SC proliferation and migration and induction of apoptosis,which may be closely related to the downregulation of the CD44/Ras signaling pathway.

Upregulated Ras/Raf/ERK1/2 signaling pathway:a new hope in the repair of spinal cord injury

An increasing number of studies report that the Ras/Raf/extracellular signal-regulated kinase 1/2 （ERK1/2） signaling pathway has a death-promoting apoptotic function in neural cells. We hypothesized that the Ras/Raf/ERK1/2 signaling pathway may be abnormally regulated in rat injured spinal cord models. The weight drop method was used to establish rat spinal cord injury at T9. Western blot analysis and immunohistochemical staining revealed Ras expression was dramatically elevated, and the phosphorylations of A-Raf, B-Raf and C-Raf were all upregulated in the injured spinal cord. Both mitogen-activated protein kinase kinase 1/2 and ERK1/2, which belong to the Ras/Raf signaling kinases, were upregulated. These results indicate that Ras/Raf/ ERK1/2 signaling may be upregulated in injured spinal cord and are involved in recovery after spinal cord injury.

VEGFR2 mediated RAS/MAPK signaling pathway to explore the mechanism of Bushen Antai Granule in the treatment of recurrent abortion

Objective:To investigate the effect of Bushen Antai Granule on the mRNA and protein expression of Ras protein/mitogen activated protein kinase mediated by vascular endothelial growth factor receptor 2 with small interference RNA interference.Methods:Method to construct the placenta microvascular endothelial cells,and the preparation of kidney fetus granule drug-containing serum,select the best drug-containing serum concentration,it can be divided into normal group,the serum siRNA-NC normal serum group,drug serum,siRNA normal serum group,siRNA drug serum group,using real-time fluorescent quantitative PCR,Western blotting,immunofluorescence test respectively the RAS/MAPK mRNA and protein expression.Results:Results there was no significant difference in Ras and MAPK mRNA and protein expression between the normal group and the negative control group(P>0.05).The mRNA and protein expressions of Ras and MAPK in the drug serum group were significantly higher than those in the normal serum group(P<0.01).Ras and MAPK mRNA and protein expression were significantly decreased in siRNA1 normal serum group compared with normal serum group(P<0.01).Ras,MAPK mRNA and protein expression in siRNA1 drug serum group were significantly different from that in siRNA1 normal serum group(P<0.01).Conclusion:Conclusion The therapeutic effect of Bushen Antai Granule on recurrent abortion may be realized by upregulation of RAS/MAPK mRNA and protein expression.

Longan Aril Reverses H2O2 Cytotoxicity in PC12 Cells via RAS/MEK/ERK Signaling Pathway

[Objectives]To explore the neuroprotective effects and mechanism of Longan Aril(LA)effective parts on PC12 cells injured by H2O2.[Methods]The neuroprotective effects of LA were evaluated by the cell viability,SOD and MDA content,apoptosis assay and relative protein expression of Aβand p-Tau.The neuroprotective mechanism of LA was studied by using metabolomics and network pharmacology,and the expressions of RAS/MEK/ERK signaling pathway-related proteins were detected by western blotting.[Results]LA could improve the cell survival rate and SOD content,and reduce apoptosis and expression of Aβand p-tau.Inhibition of RAS/MEK/ERK signaling pathway is a possible mechanism of LA neuroprotective effects.[Conclusions]LA has a neuroprotective effects in vitro and be likely to inhibit the process of AD by inhibition of RAS/MEK/ERK signalling pathway.

Maackiain inhibits proliferation and promotes apoptosis of nasopharyngeal carcinoma cells by inhibiting the MAPK/Ras signaling pathway

Nasopharyngeal carcinoma(NPC)is the third most common malignancy with a high recurrence and metastasis rate in South China.Natural compounds extracted from traditional Chinese herbal medicines have been developed and utilized for the treatment of a variety of cancers with modest properties and slight side effects.Maackiain(MA)is a type of flavonoid that was first isolated from leguminous plants,and it has been reported to relieve various nervous system disorders and exert anti-allergic as well as antiinflammatory effects.In this study,we demonstrated that MA inhibited proliferation,arrested cell cycle and induced apoptosis in nasopharyngeal carcinoma CNE1 and CNE2 cells in vitro and in vivo.The expression of the related proteins associated with these processes were consistent with the above effects.Moreover,transcriptome sequencing and subsequent Western blot experiments revealed that inhibition of the MAPK/Ras pathway may be responsible to the anti-tumor effect of MA on NPC cells.Therefore,the effects of MA and an activator of this pathway,tertiary butylhydroquinone(TBHQ),alone or combination,were investigated.The results showed TBHQ neutralized the inhibitory effects of MA.These data suggest that MA exerts its anti-tumor effect by inhibiting the MAPK/Ras signaling pathway and it has the potential to become a treatment for patients with NPC.

Spaceflight and simulated microgravity suppresses macrophage development via altered RAS/ERK/NFκB and metabolic pathways

Spaceflight-associated immune system weakening ultimately limits the ability of humans to expand their presence beyond the earth's orbit. A mechanistic study of microgravity-regulated immune cell function is necessary to overcome this challenge. Here, we demonstrate that both spaceflight (real) and simulated microgravity significantly reduce macrophage differentiation, decrease macrophage quantity and functional polarization, and lead to metabolic reprogramming, as demonstrated by changes in gene expression profiles. Moreover, we identified RAS/ERK/NFκB as a major microgravity-regulated pathway. Exogenous ERK and NFκB activators significantly counteracted the effect of microgravity on macrophage differentiation. In addition, microgravity also affects the p53 pathway, which we verified by RT-qPCR and Western blot. Collectively, our data reveal a new mechanism for the effects of microgravity on macrophage development and provide potential molecular targets for the prevention or treatment of macrophage differentiation deficiency in spaceflight.

C-X-C chemokine receptor type 7 antibody enhances neural plasticity after ischemic stroke

Stromal cell-derived factor-1 and its receptor C-X-C chemokine receptor 4(CXCR4) have been shown to regulate neural regeneration after stroke.Howeve r,whether stromal cell-derived factor-1 receptor CXCR7,which is widely distributed in the develo ping and adult central nervous system,participates in neural regeneration remains poorly unde rstood.In this study,we established rat models of focal cerebral ischemia by injecting endothelin-1 into the cerebral co rtex and striatum.Starting on day 7 after injury,CXCR7-neutralizing antibody was injected into the lateral ventricle using a micro drug delivery system for 6 consecutive days.Our results showed that CXCR7-neutralizing antibody increased the total length and number of sprouting co rticospinal tra ct fibers in rats with cerebral ischemia,increased the expression of vesicular glutamate transporter 1 and growth-related protein 43,marke rs of the denervated spinal cord synapses,and promoted the differentiation and maturation of oligodendrocyte progenitor cells in the striatum.In addition,CXCR7 antibody increased the expression of CXCR4 in the striatum,increased the protein expression of RAS and ERK1/2 associated with the RAS/ERK signaling pathway,and im proved rat motor function.These findings suggest that CXCR7 improved neural functional recovery after ischemic stroke by promoting axonal regeneration,synaptogenesis,and myelin regeneration,which may be achieved by activation of CXCR4 and the RAS/ERK1/2 signaling pathway.

Apoptosis in glioma-bearing rats after neural stem cell transplantation

Abnormal activation of the Ras/Raf/Mek/Erk signaling cascade plays an important role in glioma. Inhibition of this aberrant activity could effectively hinder glioma cell proliferation and promote cell apoptosis. To investigate the mechanism of gJioblastoma treatment by neural stem ceiJ trans- plantation with respect to the Ras/Raf/Mek/Erk pathway, C6 glioma cells were prepared in sus- pension and then infused into the rat brain to establish a glioblastoma model. Neural stem cells isolated from fetal rats were then injected into the brain of this glioblastoma model. Results showed that Raf-1, Erk and Bcl-2 protein expression significantly increased, while Caspase-3 protein expression decreased. After transplantation of neural stem cells, Raf-1, Erk and Bcl-2 protein expression significantly decreased, while Caspase-3 protein expression significantly in-creased. Our findings indicate that transplantation of neural stem cells may promote apoptosis of glioma cells by inhibiting Ras/Raf/Mek/Erk signaling, and thus may represent a novel treatment approach for glioblastoma.

Treatment time influences the effects of a low-frequency pulsed electric field on synthesis of tyrosine hydroxylase and dopamine in PC12 cells

BACKGROUND： Electromagnetic radiation can influence dopamine （DA） synthesis in brain tissues or ceils, but electromagnetic frequencies, intensities, and radiation time can produce different effects. In addition, the signal pathway by which electromagnetic radiation influences DA synthesis remains controversial. OBJECTIVE： To determine tyrosine hydroxylase （TH） expression in PC12 cells and DA levels in cell culture media after different periods of low-frequency pulsed electric field （LF-PEF） stimulation, and to determine how LF-PEF signaling stimulates TH synthesis using inhibitors. DESIGN, TIME AND SETTING： A parallel, controlled, cell experiment was performed at the Laboratory of Cell Biology, School of Life Science, East China Normal University, between January and October 2006. MATERIALS： PC12 cells were purchased from the Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, China. Nerve growth factor was purchased from PeproTech, USA. The protein kinase A inhibitor, H-89, and mitogen-activated protein kinase kinase inhibitor, U0126, were purchased from Sigma, USA. METHODS： （1） Following routine culture in Dulbecco＇s modified eagle medium, primary PC12 cells were stimulated under LF-PEF （pulse frequency 50.Hz, pulse width 20 μs, peak field strength 1 V/m） for 5, 10, 15, 20, and 30 minutes. （2） Inhibitors （H-89 or U0126, 1 μmol/L） were added 30 minutes before LF-PEF stimulation for 10 minutes. MAIN OUTCOME MEASURES： （1） TH expression was determined by Western blot in PC12 cells at 0.5, 1,2, 3, and 4 days after LF-PEF stimulation. Similarly, DA was measured by high-performance liquid chromatography in media at 2, 3, 4, or 5 days after LF-PEE （2） TH expression was detected 1 day after H-89 or U0126 treatment and LF-PEE RESULTS： （1） Short-term LF-PEF stimulation （5 and 10 minutes） increased TH expression and media DA levels after short-term culture （2 days） （P 〈 0.01）, but both parameters decreased with longer culture （3 4 days） （P 〈 0.01）. Long-term LF-PEF stimulation （15, 20, or 30 minutes） decreased TH and DA synthesis, followed by a rapid increase （P 〈 0.01）. （2） H89 could completely inhibit TH expression in PC12 cells stimulated by LF-PEF for 10 minutes, while the inhibition rate of U0126 was 53.2%. CONCLUSION： Short-term LF-PEF first promotes then inhibits, while long-term LF-PEF first inhibits then promotes, TH and DA synthesis. LF-PEF stimulation regulates TH expression primarily by activating protein kinase A to regulate DA synthesis.

Oncogenic Ras/PI3K/Her2 share a common pathway in promoting cancer metastasis via inhibiting expression of p53-related ΔNp63α

Subject Code:H16With the support by the National Natural Science Foundation of China,a collaborative study by the research groups led by Prof.Xiao Zhixiong(肖智雄)from the College of Life Science,Sichuan University demonstrates thatΔNp63αis a common inhibitory target in oncogenic PI3K/Ras/Her2-induced

Daily exposure to low concentrations Tetrabromobisphenol A interferes with the thyroid hormone pathway in HepG2 cells

Tetrabromobisphenol A(TBBPA)is a flame retardant that adversely affects the environment and human health.The present study exposed HepG2 cells to low concentrations of TBBPA daily to investigate the changes in gene regulation,mainly related to pathways associated with the endocrine system.The quantitative polymerase chain reaction(qPCR)confirmed that prolonged exposure gradually activated the thyroid hormone and parathyroid hormone signaling pathways.The expression levels of genes related to the thyroid hormone signaling pathway were upregulated(1.15-8.54 times)after five generations of exposure to 1 and 81 nM TBBPA.Furthermore,co-exposure to 81 nM TBBPA and 0.5 nM thyroid hormone receptor antagonist for five generations significantly reduced the expression of thyroid hormone and parathyroid hormone receptors.Meanwhile,81 nM TBBPA inhibited the activation of the Ras pathway and downregulated Ras gene expression level(3.7 times),indicating the association between the toxic effect and thyroid hormone receptors.Additionally,our experiments revealed that the thyroid hormone pathway regulated the induction of the Ras signaling pathway by TBBPA.The study thus proves that daily exposure to TBBPA interferes with the thyroid hormone signaling pathway and subsequently the endocrine system.

NSUN2-mediated mRNA m^(5)C Modification Regulates the Progression of Hepatocellular Carcinoma

RNA modifications affect many biological processes and physiological diseases.The 5-methylcytosine(m^(5)C)modification regulates the progression of multiple tumors.However,its characteristics and functions in hepatocellular carcinoma(HCC)remain largely unknown.Here,we found that HCC tissues had a higher m^(5)C methylation level than the adjacent normal tissues.Transcriptome analysis revealed that the hypermethylated genes mainly participated in the phosphokinase signaling pathways,such as the Ras and PI3K-Akt pathways.The m^(5)C methyltransferase NSUN2 was highly expressed in HCC tissues.Interestingly,the expression of many genes was positively correlated with the expression of NSUN2,including GRB2,RNF115,AATF,ADAM15,RTN3,and HDGF.Real-time PCR assays further revealed that the expression of the mRNAs of GRB2,RNF115,and AATF decreased significantly with the down-regulation of NSUN2 expression in HCC cells.Furthermore,NSUN2 could regulate the cellular sensitivity of HCC cells to sorafenib via modulating the Ras signaling pathway.Moreover,knocking down NSUN2 caused cell cycle arrest.Taken together,our study demonstrates the vital role of NSUN2 in the progression of HCC.