Effect of SMAC Gene on Sensitivity of Lung Adenocarcinoma Cells to Paclitaxel and Cell Viability Based on caspase-3/Bcl-2/Bax Signaling Pathway / 肿瘤防治研究

Objective To investigate the effect of the SMAC gene on paclitaxel sensitivity and cellular activity in lung adenocarcinoma cells based on the caspase-3/Bcl-2/Bax signaling pathway. Methods A paclitaxel-resistant cell line A549/Taxol was established for lung adenocarcinoma, and the cells were divided into four following groups: pcDNA-NC (transfected with pcDNA-NC blank vector), pcDNA-SMAC (transfected with pcDNA-SMAC vector), siRNA-NC (transfected with siRNA-NC empty virus vector), and siRNA-SMAC groups (transfected with siRNA-SMAC lentiviral vector). The SMAC mRNA expression in cells was detected by qRT-PCR; cell sensitivity was detected by MTT; cell proliferation ability was detected by cloning assay; cell invasion ability was detected by Transwell; apoptosis ability was detected by flow cytometry assay; and caspase-3, Bcl-2 and Bax protein expression in cells were detected by Western blot analysis. Results The SMAC mRNA expression was significantly lower in A549 cells compared with BEAS-2B cells (P < 0.05). The SMAC mRNA expression was significantly higher in the pcDNA-SMAC group than that in the pcDNA-NC group cells (P < 0.05). The SMAC mRNA expression was significantly lower in the cells of the siRNA-SMAC group (P < 0.05) than that in the siRNA-NC group. The SMAC mRNA expression was significantly lower in the cells of the siRNA-SMAC group (P < 0.05) than in the siRNA-NC group. Compared with the pcDNA-NC group, the cell IC50, cell clone number, cell invasion ability, and Bcl-2 protein and Bcl-2/Bax ratio were significantly lower in the pcDNA-SMAC group, the cell resistance index reversal was 2.51-fold, and the apoptosis ability and caspase-3, as well as Bax protein expression, were significantly higher (P < 0.05). Compared with the siRNA-NC group, cell IC50, cell clone number, cell invasion ability, and Bcl-2 protein and Bcl-2/Bax ratio were significantly higher in the siRNA-SMAC group, and apoptosis ability and caspase-3 and Bax protein expression were significantly lower (P < 0.05). Conclusion High expression of SMAC increases paclitaxel sensitivity, inhibits cell growth and invasion, promotes apoptosis in lung adenocarcinoma cells, and has a regulatory effect on the caspase-3/Bcl-2/Bax signaling pathway.

Anti-hepatoma effects of Smac analogue Birinapant and its related molecular mechanism / 中国应用生理学杂志

OBJECTIVE@#To investigate the effects of Birinapant on hepatocellular carcinoma cells and its related molecular mechanisms.@*METHODS@#Human hepatocellular carcinoma cells QGY-7701 were treated with 0, 1, 5, 25 and 125 nmol/L Birinapant for 24, 48 and 72 hours respectively, each experiment 3 wells.The proliferation activity of cells, the apoptosis levels, the cells nuclear type, the mitochondrial membrane potential, the transcription and expression levels of genes and the cytotoxicity of Birinapant were analyzed.At the same time, 4-week-old male BALB/C mice were randomly divided into 5 groups, with 20 mice in each group.The mice were inguinal injected with QGY-7701 cells, and then subcutaneous injected with Birinapant (concentrations ranging from 0, 1, 5, 25, 125 μg/kg) in each group after two days, once every other day.On 18 day since first Birinapant injection, 10 mice were killed in each group to weigh tumor tissue and survival time was recorded from the remaining 10 mice.The effects of Birinapant on the growth of the tumor and the survival time of tumor-bearing mice were observed.@*RESULTS@#Compared with the negative control (NC) group, the proliferation activity of QGY-7701 was inhibited significantly after Birinapant treatment and the apoptosis levels were increased significantly (<0.01).The cell mitochondrial membrane potential was decreased and the karyotype was changed (<0.01).At the same time, the transcription and expression levels of genes cellular inhibitor of apoptosis protein 1(cIAP-1), cellular inhibitor of apoptosis protein 2(cIAP-2), ras, raf, mek and erk were significantly decreased (<0.01), while the expression levels of caspase-3 and caspase-9 genes were up-regulated (<0.01).Compared with the model group (MG), the growth of the tumor was inhibited significantly and the survival time of the tumor-bearing mice was prolonged after Birinapant treatment (<0.01).@*CONCLUSIONS@#Birinapant can inhibit the expression of cIAP-1, cIAP-2 and the proteins of Ras-Raf-MEK-ERK signal pathways, so as to activate the mitochondria mediated endogenous apoptosis pathway.Birinapant shows a certain inhibitory effect on liver cancer.

Effects of the Survivin shRNA-APC double-gene on the expressions of survivin,Cytc,Smac and Caspase-9 in the colon cancer mitochondrial apoptosis pathway / 医学研究生学报

Objective Little is known about the effect of RNAi on mitochondrial apoptotic pathways. This study aims to explore the effects of the Survivin shRNA-APC double-gene on colon cancer mitochondrial apoptosis pathway-related factors survivin,cytochrome C (Cytc),second mitochondria-derived activator of caspases (Smac),and cysteine aspartic acid specific protease 9 (Caspase-9) as well as on the apoptosis of colon cancer transplanted tumor (CCTT) cells. Methods Thirty nude mice were randomly divided into five groups of equal number,Survivin shRNA-APC double-gene,survivin shRNA,APC,empty vector and blank transfection. The CCTT model was established in the nude mice by subcutaneous injection of the colon cancer cell strains stably transfected with the Survivin shRNA-APC double-gene,survivin shRNA,APC,an empty vector and HT-29,respectively,into the mid-posterior part of the left armpit of the nude mice. The rate of tumor growth inhibition was calculated by measuring the volume and weight of the CCTTs in the nude mice. The mRNA and protein expressions of survivin,Cytc,Smac and Caspase-9 in the tumor tissue were detected by real time PCR and immunohistochemistry,respectively,and the apoptosis rate of the CCTT cells was detected by TUNEL. Results The model of CCTT was successfully established in the nude mice. Com-pared with the empty vector and blank transfection groups,the mice in the double-gene,survivin shRNA and APC groups showed sig-nificantly decreased average volume and weight of the tumor tissue (P<0.05) but increased inhibition rate of its volume and weight (P<0.05). In comparison with the survivin shRNA and APC groups,the double-gene group exhibited remarkably decreased average volume and weight of the tumor tissue (P<0.05) but increased inhibition rate of its volume and weight (P<0.05). The mRNA and pro-tein expressions of survivin were significantly lower while those of Cytc,Smac and Caspase-9 markedly higher in the double-gene,sur-vivin shRNA and APC groups than in the empty vector and blank transfection groups (P<0.05),the former even lower (P<0.05) and the latter even higher in the double-gene than in the survivin shRNA and APC groups (P<0.05). The apoptosis rate of the CCTT cells was significantly increased in the double-gene ([56.78±3.04]%),survivin shRNA ([33.61±2.02]%) and APC groups ([30.16± 1.72]%) as compared with the empty vector ([10.05±0.42]%) and blank transfection groups ([9.87±0.30])% (P<0.05),even higher in the double-gene group than in the survivin shRNA and APC groups (P<0.05). Conclusion The Survivin shRNA-APC double-gene may induce apoptosis of colon cancer transplanted tumor cells by down-regulating the expression of the apoptosis inhibitor survivin,upregulating the expressions of Cytc,Smac and Caspase-9,and suppressing the growth of the colon transplanted tumor,with more significant abilities than a single gene in regulating apoptosis-related factors,inducing cell apoptosis and inhibiting the growth of the transplanted tumor.

Effect of α-Asarone on Esophageal Eca-109 Cell Mitochondrial Apoptosis Pathway / 医药导报

Objective To discuss the effect of α-asarone on the expression level of Cyt-c,Smac,Caspase3 mRNA and protein in human esophageal carcinoma Eca-109 cell mitochondria. Methods The Eca-109 cells were cultured in vitro,and divided into the negative control group and the α-asarone treatment groups(final concentration:25,50,100 μg·mL-1).After 48 h,the morphological changes of Eca-109 cells were observed by fluorescence inversion microscope.The total RNA of cells were extracted by TRIzol method,the expressions of Cyt-c、Smac and Caspase3 were measured by RT-PCR and Western blotting. Results After Eca-109 cells were treated with different concentrations of α-asarone for 48 h,and obvious changes in the morphology were observed,the expressions of Cyt-c,Smac and Caspase3 genes and protein were increased significantly compared to the negative control group( P<0.05). Conclusion α-asarone can induce the human Eca-109 cells apoptosis by regulating expressions of mitochondrial apoptosis pathway correlation genes such as Cyt-c,Smac and Caspase3.

Progress of the anti-tumor mechanisms of Smac mimics / 国际生物医学工程杂志

The tolerance of tumor cells to treatment factors is the main reason to limit the therapeutic effect.The high expression of inhibitor of apoptosis proteins (IAPs) is an important factor in the development of therapeutic resistance in tumor cells.As an effective pro-apoptotic protein,the second mitochondria-derived activator of caspase (Smac) can significantly enhance the sensitivity of tumor cells to chemoradiotherapy and promote the apoptosis of tumor cells.However,exogenous Smac protein and its active groups can not enter the tumor cells and play their functions.Therefore,the researches on Smac mimics and their functional mechanism have become the focus of attention of researchers.In this paper,the research progress of Smac mimics and their anti-tumor mechanisms were reviewed.

Effect and mechanism of all-trans retinoic acid on cyclosporin-induced proliferation and apoptosis of glomerular mesangial cells / 器官移植

Objective To investigate the effect and mechanism of all-trans retinoic acid (ATRA) on the cyclosporin (CsA)-induced proliferation and apoptosis of glomerular mesangial cells in rat models. Methods The glomerular mesangial cells induced by different doses of CsA were treated with different doses of ATRA. MTT assay was carried out to detect cell proliferation. Hoechst 33258 fluorescent staining was adopted to observe the morphology of the apoptotic cells. Flow cytometry was conducted to detect the cellular apoptosis rate. Immunofluorescent staining was employed to quantitatively measure the expression level of mitochondria-derived pro-apoptotic Smac protein. Results Compared with the control group, administration of CsA at a dose of 0.5 μg/mL and above could suppress cellular proliferation, and use of CsA at a dose of 1.0 μg/mL and above could induce cellular apoptosis. The expression level of Smac protein was significantly up-regulated by CsA administration with a dose and time dependence (all P<0.05).Compared with the CsA group, combined administration of CsA and ATRA exerted a more significant inhibitory effect on cellular proliferation. Supplement of ATRA could significantly inhibit glomerular mesangial cellular apoptosis induced by CsA and down-regulate the expression of Smac protein with a dose dependence (both P<0.05). Conclusions CsA can inhibit cellular proliferation, induce cellular apoptosis and up-regulate the expression of Smac protein of glomerular mesangial cells. ATRA is capable of suppressing glomerular mesangial cellular apoptosis induced by CsA, which is probably mediated by the Smac signaling pathway.

The proliferative inhibition and apoptosis promotion of Smac on human lens epithelial cells / 中华实验眼科杂志

Background Posterior capsular opacification (PCO) is a primary complication after extracapsular cataract extraction.The mechanism of PCO is associated with proliferation,migration and epithelialmesenchymal transition (EMT) of human lens epithelial cells (LECs).To explore the target treatment of PCO is very important.Objective This study was to investigate the biological effects of second mitochondria-derived activator of caspases (Smac) on the proliferation and apoptosis of LECs.Methods Human LECs line (HLE-B3) and Smac-overexpressed LECs line were cultured,and the cells were transfected using small interfering RNA (siRNA)-Smac3 plasmid with green fluorescent protein (GFP) for 24 hours.Different concentration of transforming growth factor-β2 (TGF-β2) (5,10,20 and 50 μg/ml) or 200 μmol/L H2O2 were added respectively into the culture medium to establish PCO model and oxidative stress model.Cell counting kit-8 (CCK-8) assay was used to compare the cell proliferative activity among PBS group,TGF-β2 group and Smac-hyperexpression +TGF-β2 group.Flow cytometry was used to evaluate the apoptotic rate of the PBS group,H2 O2 group and siRNA-Smac+H2 O2 group.The expressions of Smac,caspase-3 and proliferating cell nuclear antigen (PCNA) mRNA and their proteins in the cells were detected by real-time quantitative PCR (RT-PCR) and Western blot.Results The GFP+ cells were≥ 80％ 12 hours after siRNA-Smac3 transfection,with the optimal plasmid of siRNA-Smac3.GFP+ cell rate was (72.32 ± 2.31)％ in the siRNA-Smac3 transfection group,which was significantly higher than that in the blank plasmid group ([4.91 ±0.24] ％) (t=116.342,P＜0.001).The relevant expression levels of Smac was 35.21 ±4.11 in the Smachyperexpression group,and that in the blank plasmid group was 15.24±2.48,with a significant difference between them (t =215.47,P＜0.05).The cell viability of 20 ng/ml TGF-β2 affected PBS group,TGF-β2 group and Smachyperepression+TGF-β2 group was (98.4 ± 1.7) ％,(98.9 ± 0.1) ％ and (64.2 ± 3.1) ％,and the cell viability of Smac-hyperepression+TGF-β2 group was significantly lower in the Smac-hyperepression+TGF-β2 group than that in the TGF-β2 group (P＜0.05).The apoptotic rate in the PBS group,H2 O2 group and siRNA-Smac+H2 O2 group were (2.9 ± 1.2) ％,(45.1 ±4.5) ％ and (27.5 ± 1.8) ％,and the apoptotic rate was evidently lower in the siRNA-Smac +H2O2 group than that in the H2O2 group (P＜0.05).RT-PCR results showed that the expression levels of caspase-3 mRNA in PBS group,H2 O2 group and siRNA-Smac + H2 O2 group were 0.321 ± 0.103,0.715 ± 0.112 and 0.479 ±0.209,respectively.Compared with the H2 O2 group,the relative expression level of caspase-3 mRNA in siRNA-Smac+ H2O2 group was significantly decreased,the difference was statistically significant (P＜ 0.05).The PCNA mRNA expression levels in PBS group,TGF-β2 group and Smac-hyperepression+TGF-β2 group were 0.299±0.013,0.645± 0.102 and 0.490±0.209,respectively.Western blot results showed that the relative expression of caspase-3 protein in siRNA-Smac+H2O2 group and H2O2 group was 0.712±0.012 and 0.973±0.051,with significant difference between the two groups (t =132.52,P＜0.05).The relative expression of PCNA protein in Smac-hyperepression+TGF-β2 group was 0.782±0.212,which was lower than 1.126±0.251 in the TGF-β2 group (P＜0.05).Conclusions Smac may prevent and treat PCO by inhibiting the proliferation and promoting apoptosis of human LECs.

Is there something else besides the proapoptotic AVPI-segment in the Smac/DIABLO protein? / ¿Existe algo adicional al segmento pro-apoptótico AVPI de la proteína Smac/DIABLO?

Abstract: In mammals, apoptosis is the main mechanism to eliminate unwanted cells, securing tissue homeostasis and consequently maintaining the health in the organism. Classically, apoptosis culminates with the activation of caspases, which are enzymes that display cysteine protease activity to degrade specific substrates implied in essential cellular processes. This process is highly regulated. A key regulation mechanism is mediated by the Inhibitor of Apoptosis Proteins (IAPs) family members, which inhibit the activated forms of caspases through physical interaction with them. Smac/DIABLO, a mitochondrial protein that is translocated to the cytoplasm in apoptotic conditions, derepresses the IAP-mediated caspase inhibition through physical interaction with IAPs. The first four amino acids (AVPI) of Smac/DIABLO mediate the interaction with IAPs and subsequent apoptosis induction. This interaction has lead to the creation of small molecules mimicking the AVPI segment for potential anticancer therapy. Nevertheless, several studies have pointed out the existence of AVPI-independent functions of Smac/DIABLO. The aim of this review was to provide a landscape of these underestimated AVPI-independent biological functions that have been observed using different approaches, such as the study of endogenous splice variant isoforms and truncated and mutated artificial proteins.

Resumen: La apoptosis es uno de los principales mecanismos en los mamíferos para eliminar células no deseadas, asegurando la homeostasis de los tejidos y, consecuentemente, la salud de los mismos. De forma clásica, la apoptosis finaliza con la activación de las caspasas, enzimas que despliegan actividad de proteasas de cisteína, involucradas en la degradación de sustratos específicos implicados en procesos celulares esenciales. El proceso apoptótico se encuentra altamente regulado. Un mecanismo de regulación es el mediado por los miembros de la familia de las Proteínas Inhibidoras de la Apoptosis (PIA), las cuales inhiben a las formas activas de las caspasas a través de la interacción física con estas. Smac/DIABLO, proteína mitocondrial que es translocada al citoplasma en condiciones apoptóticas, antagoniza la inhibición de las caspasas mediante su interacción física con las PIA. Los cuatro primeros aminoácidos (AVPI) de Smac/DIABLO intervienen en su asociación con las PIA y la subsecuente inducción apoptótica. Esto ha guiado a la generación de pequeñas moléculas miméticas del segmento AVPI para el uso potencial como una terapia anti-cancerígena. Sin embargo, varios estudios han indicado la presencia de funciones en Smac/DIABLO independientes del AVPI. El objetivo de esta revisión fue proporcionar un panorama de estas funciones biológicas desestimadas —independientes al AVPI— las cuales se han observado utilizando diferentes aproximaciones, como el estudio de las isoformas generadas por el procesamiento alternativo del gen y la síntesis de proteínas artificialmente mutadas.

Anti-tumor research targeting IAPs / 中国药理学通报

Apoptosis inhibitors ( inhibitor of apoptosis proteins, IAPs) are a class of highly conserved apoptotic endogenous anti-cytokine family, primarily by inhibiting caspase activity and par-ticipation in regulation of nuclear factor NF-κB inhibition of ap-optosis. caspases cascade of protease activation is a central part of the apoptotic process, Bcl-2 family proteins and IAPs family proteins are the main controlling factors. In recent years, we found that abnormal expression of some IAPs members is closely associated with the tumor, a potential target for cancer therapy. Therefore, this paper reviews the major protein associated with IAPs family and anti-tumor research targeting IAPs.

Expressions of pro-apoptotic protein Smac and HtrA2 in children with acute leukemia and its clinical significance / 中华实用儿科临床杂志

Objective To investigate the expression and clinical significance of Smac and HtrA2 in children with acute leukemia(AL).Methods Bone marrow samples were obtained from 77 children with AL (including 32 newly diagnosed children,33 complete remission children and 12 relapsed children)and the control group of 15 children without malignant blood disease.The expressions of Smac and HtrA2 protein were measured by streptavidin/peroxidase immunoperoxidase technique(SP) in all children.SPSS 13.0 software was applied to analyze the statistical data.Results Protein Smac was detected only in some samples,but HtrA2 was detected in all samples.The levels of Smac and HtrA2 protein in newly diagnosed AL children were both higher than those of the complete remission children (x2 =17.38,F =2.36,all P ＜ 0.05) and normal controls (x2 =12.89,F =5.26,all P ＜ 0.05),there was a statistical significance,but compared with those in the relapsed children,the difference had no statistical significance (x2 =1.18,F =1.57,all P ＞ 0.05).The levels of Smac and HtrA2 protein in complete remission children were both higher than those of the normal controls,and the difference had no statistical sigmficance(x2 =1.20,F =2.23,all P ＞ 0.05).In the newly diagnosed children,the levels of Smac and HtrA2 protein in children with acute lymphocytic leukemia(ALL) were higher than those of the acute myeloid leukemia(AML),but the differences had no statistical significance(x2 =0.113,t =1.024,all P ＞ 0.05).In newly diagnosed AL children,the complete remission(CR) rate of the negative expression of Smac(Smac-,90.9％) and the low expression of HtrA2(HtrA2low,84.6％) in the level of protein were higher than those of the positive expression of Smac(Smac +,47.6％) and the high expression of HtrA2 (HtrA2high,47.4％),and there was statistical significance respectively(x2 =5.772,4.596,all P ＜ 0.05).The CR rate of Smac-HtrA2low group (100％) was higher than that of Smac+ HtrA2high group(30.8％)in the children with AL,and the statistical data were of great significance(x =9.692,P ＜0.01).The protein level of Smac in newly diagnosed AL children was correlatedwith HtrA2 (r =0.979,P ＜ 0.001).Conclusions Pro-apoptotic protein Smac and HtrA2 may be involved in and af-fected each other in the pathogenesis and progression in AL,but levels of Smac and HtrA2 protein may be not correlatedwith the types of AL.In newly diagnosed AL children,the high expression of protein Smac and HtrA2 predicts poorprognosis.

Research progress of ovarian cancer apoptosis related factor-Survivin and Smac / 国际肿瘤学杂志

Survivin is the strongest member of the inhibitor of apoptosis protein(IAP)family. Smac is the second mitochondria-derived activator of cysteine proteases,which can promote apoptosis by combining with IAP. Abnormal expression of them is closely related with occurrence,development,treatment tolerance and prognosis of ovarian cancer. It is prompted that Survivin and Smac are expected to play important roles in the early diagnosis and targeted therapy of ovarian cancer.

Smac playing vital role in enhancing the sensitivity of cyclophosphamide and doxorubicin in breast cancer MCF-7 cell line / 国际肿瘤学杂志

Objective To investigate the influence of Smac to the chemosensitivity of cyclophosphamide (CTX) and doxorubicin (DOX) in MCF-7 cells.Methods MCF-7 cells were exposed to CTX,DOX and the combination of both.3-(4,5-dimethyl-2-thiazoly)-2,5-diphenyl-2 H-tetrazolium bromide (MTT) assay was used to estimate the cell viability.Apoptosis was measured by acridine orange staining and Ho.33342/PI dou-ble staining.The mRNA and protein expressions of Smac were determined by RT-PCR and Western blotting.The study also analyzed the changes of pro-apoptotic proteins active caspase-3 and active caspase-9.Results CTX,DOX and the combination of both drugs reduced the cell survival rates in a concentration-dependent manner.The cell viability after being treated with 4.0 μg/ml CTX or 0.2 μg/ml DOX or 2.0 μg/ml CTX and 0.1 μg/ml DOX for 48 hours was (52.90 ± 8.78) ％,(53.35 ± 6.29) ％ and (34.19 ± 5.43) ％,respectively.The drug combination developed a stronger inhibitory effect compared to the single drugs (t =9.051,P=0.014;t =9.074,P =0.014).The Smac mRNA and protein levels in 2.0 μg/ml CTX and 0.1 μg/ml DOX group were 7.47 ± 0.82 and 4.13 ± 0.36,which were higher than those in 4.0 μg/ml CTX group (3.27 ± 0.40 and 2.28 ± 0.27;t =-50.120,P =0.000;t =-42.588,P =0.000) and 0.2 μg/ml DOXgroup (3.34±0.62and2.45±0.40;t=-46.233,P=0.000;t=-39.541,P=0.000).Furthermore,pro-apoptotic proteins active caspase-3 and active caspase-9 increased activity was confirmed by Western blotting.Conclusion Smac plays a vital role in enhancing the sensitivity of chemotherapeutic drugs CTX and DOX in MCF-7 cell line.

Smac Involved in Promoting TGF-β1 Treated Mesangial Cells Apoptosis Induced by Triptolide / 天津医药

Objective To investigate the effects of Triptolide on apoptosis of cultured rat mesangial cells treated by TGF-β1 and the role of Smac in this process. Methods The mesangial cells were pre-treated with different concentrations of Triptolide for 24 hours, then stimulated with TGF-β1 for 24 hours. Apoptotic cells were detected by TUNEL assay. Smac transcription level was determined by Real time-PCR analyses. Smac expression level was assessed using Western blot anal-yses. Localization of Smac was shown by confocal fluorescence microscopy. Results Compared with control group, TGF-β1 inhibited apoptosis and Smac transcription and expression in rat mesangial cells. By contrast, Triptolide promoted mesangial cells apoptosis. In Triptolide groups, Smac mRNA and protein levels were up-regulated. Additionally, in normal and TGF-β1 groups Smac protein was mainly localized in mitochondriawhile in Triptolide groupit was mainly localized in cytoplasm and nucleus with increased fluorescence intensity. Conclusion Triptolide could promote the effect that TGF-β1 inhibited apop-tosis of mesangial cells, through both up-regulation the expression of Smac and stimulating it translocation from mitochon-dria to cytoplasm and nucleus.

Expression of XIAP and Smac in human non-small-cell lung carcinoma(NSCLC)and the relationship with clinical significance and prognosis / 中国肿瘤临床

Objective:To investigate the expression of XIAP and Smac in human non-small-cell lung carcinoma (NSCLC) and the relationship with clinical significance and prognosis. Methods:Immunohistochemical staining was performed to determine the ex-pression of X-linked inhibitor of apoptosis protein (XIAP) and second mitochondria-derived activator of caspase (Smac) in 70 cases of NSCLC and 70 cases of non-cancerous adjacent lung tissues. Results:XIAP is mostly present (59/70) in tumor tissues with 16 high ex-pressions, whereas only five high expressions in non-cancerous adjacent lung tissues are observed (52/70). The statistical difference of these two sets of data is significant (Z=-5.484, P0.05). The Kaplan-Meier analysis results show that survival by XIAP and Smac protein in NSCLC has no significant effect (P>0.05). Conclusion:XIAP and Smac are expressed in NSCLC and noncancerous adjacent lung tissues, and the differences in their expression levels is significant. The deterioration of NSCLC results in apoptosis/anti-apoptotic synchronized with tumor cell proliferation. The expression levels of XIAP and Smac in NSCLC are not related with the prognosis.

Inhibitory effect of pshuttle-Egr-1-hSmac plasmid combined with X-ray irradiation on proliferation of breast cancer MDA-MB-435 cells / 吉林大学学报(医学版)

Objective To construct the pshuttle-Egr-1-hSmac plasmid and transfect human breast cancer MDA-MB-435 cells,and to observe its radiotherapy enhancing effect on tumor cells.Methods The empty vector pshuttle and pshuttle-Egr-1-hSmac plasmid were transfected into MDA-MB-435 cells by liposomal.At different time(4,8,12,24 and 48 h)after irradiation with 2.0 Gy X-ray and 24 h after irradiation with 0.5 -5.0 Gy,the total RNA and protein were collected and extracted from these cells to analyze the Smac mRNA and protein expression levels with RT-PCR and Western blotting methods. The cells were divided into control, pshuttle, pshuttle-Egr-1-hSmac,2.0 Gy irradiation group, pshuttle + 2.0 Gy irradiation and pshuttle-Egr-1-hSmac+2.0 Gy irradiation groups.MTT method was used to evaluate cell proliferation,and the cell survival ability was measured with clone formation assay;Annexin Ⅴ/PI double staining and PI single staining were used to examine the apoptosis and cell cycle of MDA-MB-435 cells. Results There was no Smac mRNA expression in MDA-MB-435 cells in control and pshuttle groups,but the Smac mRNA expression levels in MDA-MB-435 cells in pshuttle-Egr-1-hSmac plasmid group were gradually increased with the time prolongation, and reached the maximum at 24 and 48 h;the Smac mRNA expression levels in MDA-MB-435 cells were increased gradually 24 h after irradiation of 0.5 - 5.0 Gy X-ray with the increasing of irradiation doses, and reached the maximum after 2.0 and 5.0 Gy irradiation. The Smac protein expression levels in pshuttle-Egr-1-hSmac plasmid group were increased gradually with the time prolongation,and reached the maximum at 24 h.The Smac protein expression lervels were increased 24 h afer irradiation of 0,0.5,1.0,2.0 and 5.0 Gy X-ray,especially in 5.0 Gy group. The MTT results showed that the A490 values in 2.0 Gy,pshuttle+2.0 Gy and pshuttle-Egr-1-hSmac groups 24, 48,and 72 h after irradiation were lower than those in control group(P<0.01);the A490 values of MDA-MB-435 cells in pshuttle-Egr-1-hSmac group after 1.0-5.0 Gy X-ray irradiation were lower than those in 0 Gy group (P<0.05 or P<0.01);the survival fraction(SF)in pshuttle-Egr-1-hSmac group was lower than those in control group (P<0.01).The percentages of the cells at G0/G1 and S phase in pshuttle-Egr-1-hSmac group were lower than those in 2.0 Gy group(P<0.01),the percentage of the cells at G2/M phase was higher than that in 2.0 Gy group (P<0.01);the apoptotic rate of the cells in pshuttle-Egr-1-hSmac group was higher than that in 2.0 Gy group (P<0.01).Conclusion X-ray irradiation can significantly increase the Smac mRNA and protein expression levels in MDA-MB-435 cells transfected with pshuttle-Egr-1-hSmac plasmid,inhibit the cell survival rate,and induce G2/M arrest and apoptotic increasing;Smac gene combined with radiotherapy could significantly increase the radiosensitivity of breast cancer cells.

Construction of specific interference vector and lentiviral packaging for SMAC gene in mice / 临床肝胆病杂志

Objective To construct and identify the specific interference vector for second mitochondria -derived activator of caspase (SMAC)gene in mice and perform lentiviral packaging.Methods According to the SMAC gene sequences in mice,three small interfering RNAs (siRNAs)(siRNA1,siRNA2,and siRNA3)and one negative control sequence (siRNAn)were designed and synthesized,and mouse hepatocytes were transfected with the above siRNAs using Lipofectamine 2000.The inhibitory effects of these siRNAs on SMAC mR-NA expression were evaluated by real-time PCR,and the optimal siRNA was screened out accordingly.Oligo DNA was synthesized based on the optimal siRNA and then connected to GV1 15 vector to obtain recombinant interference plasmid.The candidate clones were identified by PCR and sequenced.The recombinant interference plasmid,as well as pHelper 1.0 and pHelper 2.0,was used to transfect 293T cells for lentivirus packaging.Then,cell supernatants were collected and concentrated,and the lentiviral titer was determined by gradient dilution. Comparison between groups was made by analysis of variance,and multiple comparisons were made by SNK-q test.Results The three siRNAs had different inhibitory effects on SMAC mRNA expression in hepatocytes;siRNA1 showed the strongest inhibitory effect,with an inhibition efficiency of 70.3%.Based on siRNA1 ,the oligo DNA was successfully synthesized and correctly connected to the lentiviral vec-tor,as proved by sequencing.The lentiviral titer was 6 ×108 TU/ml,as determined by gradient dilution.Conclusion The recombinant lentivirus that inhibits SMAC expression in mice has been constructed successfully,laying the foundation for further studies on the role of SMAC gene in liver failure.

NF-κB silencing combined with matrine-induced apoptosis in hepatocellular carcinoma cells and expression of related molecules / 第二军医大学学报

Objective: To investigate the apoptosis in hepatocellular carcinoma cells induced by NF-κB silencing combined with matrine (MT) and the expression of related molecules. Methods: The recombinant eukaaryotic expression plasmid NF-κB/ P65 siRNA was constructed and transfected into HepG2 cells. RT-PCR was used to detect the efficiency of the constructed RNAi in silencing NF-κB/P65, and the steadily transfected clones of NF-κB/P65 RNAi were selected. The cultured HepG2 cells was randomly divided into four groups: control group, MT group (1.5 g/L), steadily transfected group and combination group(steadily transfected cells+MT). The apoptosis of carcinoma cells was analyzed by flow cytometry; expression of NF-κB/P65, CD95(Fas), Smac, and Survivin mRNA and protein in carcinoma cells was examined by RT-PCR and Western blotting analysis. Results: The expression of NF-κB/P65, CD95(Fas), Smac, and Survivin mRNA and protein in MT group was significantly increased compared with that in the control group (P<0.05). The expression of CD95 and Smac in the steadily transfected group was significantly higher than that in the control group (P<0.05), and the expression of NF-κB/P65 and Survivin was significantly suppressed compared with the control group and the MT group(P<0.05). The expression of CD95 and Smac in the combination group was significantly increased compared with that in the other three groups(P<0. 05), and the expression of NF-κB/P65 and Survivin was significantly lower than that in the MT group(P<0. 05). The apoptosis rates of the HepG2 cells in the control group, MT group, steadily transfected group, and combination group were 3. 21%, 6.25%, 11. 82%, and 21. 06%, respectively, with significant difference found between different groups(P<0. 05). Conclusion: The apoptosis in hepatocellular carcinoma cells induced by NF-κB RNAi combined with matrine may be related to increased CD95 and Smac expression and decreased NF-κB/P65 and Survivin expression.

Effect of Smac on TRAIL-induced Apoptosis of Prostate Cancer Cell Line PC-3 and the Molecular Mechanism / 华中科技大学学报（医学）（英德文版）

The effect of Smac gene on the TRAIL-induced apoptosis of the prostate cancer cell line PC-3 and the molecular mechanism were investigated.The Smac gene was transfected into PC-3 cells under the induction of liposome.The intrinsic Smac gene expression was detected by Western blotting.After treatment with TRAIL as an apoptosis inducer,in vitro cell growth activity was assayed by MTT colorimetry.The apoptosis rate of PC-3 cells was determined by annexin V -FITC and propidium iodide staining flow cytometry.The expression of cellular XIAP and caspase-3 genes was examined by Western blotting.Smac-transfected cells (PC-3/Smac group) had significantly increased Smac protein level as compared with PC-3 controls (P＜0.01).After induction with 100-200 ng/mL TRAIL for 12-36 h,cellular proliferation rate in PC-3/Smac group was significantly lower than in PC-3 controls (P＜0.05).After induction with 100 ng/mL TRAIL for 24 h,the apoptosis rate in PC-3/Smac group was significantly enhanced as compared with that of PC-3 controls (P＜0.05).Accordingly,the XIAP expression level was down-regulated significantly (P＜0.05) and caspase-3 subunit P20 was up-regulated significantly (P＜0.05).It is suggested that the over-expression of cellular Smac can inhibit inhibitor of apoptosis proteins (IAPs),enhance caspases activity and the apoptosis rate of PC-3 cells induced by TRAIL,which may provide a useful experimental basis for prostate cancer therapy.

Expression and clinical significance of Livin and Smac protein in pancreatic carcinoma / 中华胰腺病杂志

Objective To investigate the expression and clinical significance of apoptosis inhibitory protein, Livin and Smac,in pancreatic carcinoma. Methods The expressions of Livin and Smac protein in 46 cases of pancreatic carcinoma tissues and 15 cases of insulinoma tissues and 14 cases of normal pancreatic tissues were examined by using immunohistochemical SP staining, and its relationship with clinicopathological parameters was analyzed. Results The positive expression rates of Llivin protein were 73.9％ ( 34/46),73.3％ (11/15) and 14.3％ (2/14) in pancreatic carcinoma, insulinoma and normal pancreatic tissue. Livin was highly expressed in pancreatic carcinoma and insulinoma, but there was no significant difference between the two groups, however, both were significantly higher than that in normal pancreatic tissues group ( P ＜ 0.05 ). The expression of Livin was significantly correlated with lymph node metastasis, histopathological grading and clinical staging (P ＜ 0.05 or P ＜0.01 ). The positive expression rates of Smac protein were 39.1％ (18/46), 100％ ( 15/15 ) and 92.9％ (13/14) in pancreatic carcinoma, insulinoma and normal pancreatic tissue. Smac was highly expressed in normal pancreatic tissues and insulinoma, but there was no significant difference between the two groups, however, both were significantly higher than that in pancreatic cancer group (P ＜ 0.05 ). The expression rote of Smac protein was significantly correlated with lymph node metastasis, histopathological grading, chnical staging and patients' age (P ＜0.05 or P ＜0.01 ).Conclusions Livin protein may play an important role in genesis and development of pancreatic carcinoma,but Smac protein may play a role in preventing the development of pancreatic carcinoma.

The expression and clinical significance of Livin and Smac in patients with non-Hodgkin lymphoma / 白血病·淋巴瘤

Objective To study the expression and clinical significance of Livin ( anti-apoptosis protein) and Smac (promoting apoptosis factor) in patients with the non-Hodgkin lymphoma (NHL).Methods The expression of Livin and Smac were detected by immunohistochemical staining(SP) assay in 31 patients with NHL, and the relationship between Livin/Smac and clinical staging, IPI and prognosis were analyzed. Results The patients with positive expression of Livin had B symptom, high risk IPI, late clinical staging (Ⅲ/Ⅳ stage) and short survival time, while the ones with positive expression of Smac had no B symptom, early clinical staging( Ⅰ /Ⅱ stage), low risk IPI and good prognosis. The expressions of both Livin and Smac were not related to gender and age. Expression of Livin was not correlated to that of Smac (r =0.003,P ＞0.05). Conclusion For patients with NHL, the expression of Livin protein was related to poor prognosis and adverse clinical features, whereas the expression of Smac protein was related to good prognosis and clinical feature.