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.

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.

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.

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.