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Purpose To explore the expression,significance and relationship of apoptosis related gene Apollon and Caspase 9 in gastric carcinoma. Methods The SP immunohistochemical method was used to detect the expression of Apollon and Caspase 9 in 105 cases of gastric carcinoma,38 adjacent tissues and 29 normal tissues,and the expression of Apollon and Caspase 9 was analyzed with relation to clinicopathologic factors. Results The numbers of positive expression of Apollon gene in gastric carcinoma tissues,adjacent tissues and normal tissues were 82(78. 10％) ,8(21. 05％) and 2(6. 90％) respectively, there was significant difference between gastric carcinoma tissues, adjacent tissues and normal tissues (P < 0. 01) . The expression of Apollon in gastric carcinoma was positively correlated with degree of tumor differentiation,TNM staging and lymph node metastasis (P < 0. 05) ,but not with other clinicopathologic factors (P > 0. 05) . The numbers of positive expression of Caspase 9 gene in gastric carcinoma tissues,adjacent tissues and normal tissues were 21 (20. 00％) ,23 (60. 53％) and 21 (72. 41％) ,respectively,and there was significant difference between gastric carcinoma tissues,adjacent tissues and normal tissues (P < 0. 01) . The expression of Caspase 9 in gastric carcinoma was positively correlated with degree of tumor differentiation, TNM staging and lymph node metastasis (P < 0. 01) ,but not with other clinicopathologic factors (P > 0. 05) . The expression of Apollon was negatively correlated to Caspase 9 in gastric carcinoma with statistical significance (r = - 0. 541 1,P < 0. 01) . Conclusions The interaction of Apollon and Caspase 9 may be involved in the gastric carcinogenesis and progression. Apollon is closely related with invasion and metastasis of gastric carcinoma,and it may be a potential treatment target.
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Cervical cancer is the second common cause of cancer deaths in women worldwide. Radioresistancy of cancer is a principal cause of treatment impairing. Inhibitor of apoptosis proteins (IAPs) widely block apoptosis against apoptotic stimuli, including current chemo- and radiation therapies. Apollon, a membrane of IAP, can support cells against apoptosis and is over expressed in some treatment-resistant cancer cells. The aim of this study was to evaluate the effects of apollon knockdown on induction of apoptosis and also its potential for enhancement of radiosensitvity on hela cells. plasmid encoding shRNA which has been confirmed its effect against apollon, transfected into hela cells. Consequent effects on the level of P53 , Bax and BAK analyzed by real time PCR. Apoptotic phenotype of transfected cells was monitored by Tunnel assay. Viability of hela cells after radiotherapy was analyzed by MTT assay. shRNA1 effectively increased transcription of p53, Bax and BAK and induced apoptosis phenotype of treated hela cells. Radiosensitivity of transfected cell was increased after knock-down of apollon obviously. Apollon knockdown induces apoptosis in hela cell . Also it can be as new molecular target for radio-sensitizing strategies in these cells. So, apollon can be a potentially considerable therapeutic object for cervical cancer.
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Objective To study the effect of small interfering RNA targeted on Apollon for proliferation on pancreatic cancer cells and its possible acting mechanism.Methods The small interfering RNA targeted on apollon in our previous study was transfected to the cells using LipofectamineTM 2000,after 48 hours transtection.The inhibitory effects of small interfering RNA targeted on Apollon (Apollon siRNA)on cell proliferation were detected by WST-8.Their inhibition rate and IC50 were calculated.The percentage of apoptosis cells were determined by flow cytometry.The expression of Apollon mRNA was analyzed by real time fluorescent quantitative reverse transcription polymerase chain reaction.The Apollon protein ex-pression levels were detected by western blotting.Results Apollon siRNA could effectively inhibit the proliferation of pan-creatic cancer cell.The amount of apoptotic cells increased significantly.The early apoptotic rate was 37.1%,and the RT-PCR results showed that the relative expression levels of Apollon mRNA were down-regulate,and shows a dose-effective-ness relations.The protein expression levels were decreased by Apollon siRNA.Conclusion Apollon siRNA can effectively inhibit the proliferation of pancreatic cancer cell.The mechanism may be work together to promote pancreative cancer cell early apoptosis and decreased the expression levels of gene and protein,which provides a novel potential approach for treat-ment of target therapy of pancreatic cancer.
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Objective To screen siRNAs that can effectively inhibit Apollon gene expression and determine the cellular functions of those siRNAs.Methods A chemical synthesis method was used to synthesize 3 siRNA sequences against different sites of Apollon.They were transfected into the human breast cancer MCF-7 cells by using Lipofectamine 2000.mRNA level of Apollon was determined by reverse transcription-polymerase chain reaction (RT-PCR).Cellular immunity fluorescence quantitative analysis combined with confocal laser technology was used to determine the protein level of Apollon.Methyl thiazolyl tetrazolium bromide (MTT) assay and flow cytometry were used to determine the effects of siRNA targeting Apollon on proliferation and apoptosis of MCF-7 cells,respectively.Results Three pairs of siRNA could significantly inhibit Apollon mRNA expression,at the inhibition rates of (36.201±11.629) ％,(67.308±7.686) ％and (47.123±12.000) ％,respectively (P ＜ 0.05).After tranfection by siRNA2,Apollon protein fluorescence intensity was (14.97±2.08) ％ compared with control cells.The cell proliferation MCF-7 was inhibited by (73.361±2.118) ％and apoptosis was increased by (28.793±0.743) ％.Conclusions Screened siRNA2 effectively silences Apollon gene expression,effectively inhibits the proliferation and increases the apoptosis of MCF-7 cells.This provids the foundation for its clinical application in cancer therapy.
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Background and purpose:Apollon gene is highly expressed in leukemia and other tumors. The study aimed to discuss whether RNAi technology can reverse multidrug resistance of chronic myeloid leukemia cell line K562 through constructing a eukaryotic vector of short hairpin RNA (shRNA) targeting at Apollon gene. Methods:The eukaryotic vector pGPHI-GFP-Neo-Apollon with shRNA targeting at Apollon gene was constructed and then transfected into K562 cells by LipofectamineTM2000, and G418 pressure selection. Reverse transcription-polymerase chain reaction (RT-PCR) and immunolfuorescence were used to detect the expression of Apollon mRNA and protein after Apollon was transfected stably in K562 cells. The changes of sensitivity of K562 cells to leurocristine (VCR) and etoposide (VP16) after transfection with shRNA-Apollon were detected by MTT method, and the apoptosis rate was detected by flow cytometry. Results: pGPHI-GFP-Neo-Apollon carrier was constructed successfully and expressed stably in K562 cells, and after G418 screening, it silenced Apollon mRNA and protein expression effectively. According to the result of MTT, the sensitivity of K562 cells to VCR and VP16 increased significantly in the group of gene interference, with half of its inhibition concentration (half-inhibitory, IC50) value signiifcantly lower than the control group (P0.05). Conclusion:pGPHI-GFP-Neo-Apollon carrier can enhance the abilities of VCR and VP16 to induce the apoptosis of K562 cells, namely an increase of sensitivity to these chemotherapeutics in K562 cells, it is hinted that RNA interference targeting Apollon gene may reverse the multidrug resistance of leukemia cells in some degree.
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Objective To investigate the effects of Apollon antisense oligonucleotide (ASODN) on proliferation,apoptosis and drug resistance of human leukemia(K562) cells.Methods Specific phosphorothioate ASODN and missense oligonucleotide (MSODN) of Apollon mRNA were synthesized and transfected into K562 cells following cationic liposome.The proliferation inhibition of K562 cells was assessed by MTT.The apoptosis rate was detected by Annexin V-FITC.The sensitivity of K562 cells to etoposide and vincristine was detected by MTT.Results Apollon antisense oligonucleotide inhibition of K562 cells with the concentration and time increased.ASODN at a final concentration of 600 nmol/L could significantly inhibit the K562 cell proliferation.The apoptosis rate was apparently increased (P ＜ 0.01).Conclusions Apollon ASODN may decrease Apollon gene expression,suppress K562 cells proliferation effectively,and induce significant apoptosis of K562 cells.Apollon ASODN is able to reverse the drug resistance via inhibition of Apollon expression and inducement of apoptosis.
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Apollon is a member of inhibitor of apoptosis proteins. It can inhibit apoptosis through inter-action with Smac, HtrA2 and caspase. Apollon is highly expressed in a variety of tumors, such as leukemia, breast cancer, brain cancer, carcinoma of mouth and carcinoma of stomach. Apollon may relate with genesis and prognosis of tumor . It also may lead to drug resistance of certain tumors.