Tm Induce Apoptosis Mediated By Endocytoplasmic Reticulum Stress In Gastric Cancer Cell

Objective:Endoplasmic reticulum(ER) is the site of synthesis and folding of secretory proteins.Unfolded or misfolded proteins are harmful to cells in that ceil survival can be threatened.Perturbation of ER homeostasis affect protein folding and cause ER stress.ER can sense the stress and respond to it through translational attenuation,up regulation of the genes for ER chaperones and related proteins,and degradation of unfolded proteins by a quality-control system.However,when the ER function is severely impaired,the organelle elicits apoptotic signals.However,they are impaired under various physiological and pathological conditions,collectively called "ER stress",Endoplasmic reticulum stress has an important role in determining the outcome of cells such as stress resistance, adaptation,injury or apoptosis.Endoplasmic reticulum proteins,one of the most important are glucose-regulated protein GRP family GRP78/BIP,protective effect on cells,restore the correct protein conformation;At the same time,transcription factor ATF6 and PEKR transmembrane protein kinase activation can induce a series of endoplasmic reticulum stress transcription of target gene expression.One of GADD153/CHOP gene encoding protein can reduce the expression of Bcl-2,so that the skin cells Valley GSH depletion caused by apoptosis,resulting in growth cessation and cell death play a role. Endoplasmic reticulum stress response time is too long or strong,but also activation of the endoplasmic reticulum located in the skin of semi-aspartyl enzyme -12 and then the skin caused by semi-aspartyl enzyme cascade,resulting in apoptosis.CHOP is a 27 kDa protein with 169(human) or 168(rodents) amino-acid residues.CHOP protein was first identified to be a member of the CCAAT/enhancer binding proteins(C/EBPs) that serves as a dominant negative inhibitor of C/EBPs.CHOP is also known as growth arrest- and DNA damage inducible gene 153 (GADD153).There are three distinct three genes,but there is no similarity among them.C/EBPs form a family of transcription factors that regulate a variety of genes involved in a broad range of physiological processes,including immune functions as well as cell differentiation and proliferation.CHOP is ubiquitously expressed at very low levels.However,it is robustly expressed by perturbation that induce stress in a wide variety of cells.CHOP is present in the cytosol under nonstressed conditions,and stress leads to induction of CHOP and its accumulation in the nucleus.CHOP is a golden standard in ER stress.Research proves that TM at the nervous system,pancreatic cells,such as in ER stress mediated apoptosis,But have not yet seen in the gastric cancer cell ER stress mediated apoptosis-related reports. TM with 10μg/ml was at different times of gastric cancer cells BGC823,From the gene level and protein expression level of TM-induced gastric cancer BGC823 cell detect endoplasmic reticulum stress-mediated apoptosis,TM may induce apoptosis mediated by ERS in gastric cancer cell BGC823.Methods:(1) Gastric cancer cell BGC823 were cultured in vitro,and was treated with 10μg/mlTM for Oh,24h,36 h and 48 hrespectively in the logarithmic phase of cells.(2) The culture state of Gastric cancer cell BGC823 was observed in living cells, Endoplasmic reticulum stress was observed by Annexin V-PI staining.(3) RT-PCR was used to detect the effect ofTM on CHOP gene expression at Oh,24h,36h,48h respectively.(4) Western blot technology was used to detect the expression level of CHOP protein before and after treated withTM.So TM induce apoptosis mediated by endocytoplasmic reticulum stress in gastric cancer celll.(5) SPSS 10.0 software was applied for the data statistics.(?)±s was used to compare these data.α=0.05 was considered significant.Results:(1) From the culture state,Gastric cancer cell BGC823 changed the status of a cell density and the level of aggregation decreased.There were most of the disparity between the cell size difference,and the cell debris multed after treated with TM. Membrane budding off into different sizes,such as apoptotic bodies change.(2) Gastric cancer cell BGC823 were treated with 10μg/ml of TM for Oh,24h,36h and 48h respectively.Apoptosis was evaluated by using Annexin V-PI staining. Under fluorescence microscope showing green fluorescent cells for apoptotic cells, red fluorescent cells as dead cells.(3) TM-induced gastric cancer cells BGC823 endoplasmic reticulum stress-mediated apoptosis have emerged in the course of CHOP expression,and CHOP-mRNA expression level of time-dependent existence.Must have at conditions, with the processing time for growth,expression levels also increased.(4) Western-blot results showed that TM-induced gastric cancer cells BGC823 endoplasmic reticulum stress-mediated apoptosis have emerged in the course of CHOP expression,and the expression of CHOP protein levels in time-dependent existence.Must have at conditions,with the processing time for growth,expression levels also increased.Conclusions:TM can induce gastric cancer cells BGC823 endoplasmic reticulum stress-mediated apoptosis...