SMAC exhibits anti-tumor effects in ECA109 cells by regulating expression of inhibitor of apoptosis protein family

BACKGROUND The poor prognosis and rising incidence of esophageal cancer highlight the need for improved therapeutics that are essential prior to treatment.LCL161 is an SMAC(second mitochondrial activator of caspases)mimic and inhibitor of apoptosis protein(IAP)antagonist which exhibits anti-tumor effects and improves the chemical sensitivity of many cancers.AIM To ascertain the effects and mechanisms of the SMAC analog LCL161 on esophageal cancer cells.METHODS MTT assay and TUNEL assay were used to detect cell proliferation and apoptosis,respectively.Western blot analysis was used to study the molecular mechanisms of LCL161-induced death of ECA109 cells.RESULTS LCL161 decreased ECA109 cell proliferation in dose-and time-dependent manner and induced apoptosis of ECA109 cells in a dose-dependent manner.Also,LCL161 induced a significant decrease in the expression of the XIAP and significant increase in the expression of Caspase-3.In addition,Bax increased significantly with increasing concentrations of LCL161,and the relative expression of Bax was significantly different between groups.CONCLUSION These findings support the hypothesis that LCL161 can inhibit proliferation and induce apoptosis in esophageal cancer cells by regulating the expression of IAP family members,suggesting that it has potential to be an effective treatment for esophageal squamous cell carcinoma.

Human antigen R mediated post-transcriptional regulation of inhibitors of apoptosis proteins in pancreatic cancer

AIM To determine the association of human antigen R(HuR) and inhibitors of apoptosis proteins(IAP1, IAP2) and prognosis in pancreatic cancer.METHODS Protein and mRNA expression levels of IAP1, IAP2 and HuR in pancreatic ductal adenocarcinoma(PDAC) were compared with normal pancreatic tissue. The correlations among IAP1/IAP2 and HuR as well as their respective correlations with clinicopathological parameters were analyzed. The Kaplan-Meier method and log-rank tests were used for survival analysis. Immunoprecipitation assay was performed to demonstrate HuR binding to IAP1, IAP2 mRNA. PANC1 cells were transfected with either anti-HuR siRNA or control siRNA for 72 h and quantitative reverse transcription polymerase chain reaction(RT-PCR), western blot analysis was carried out.RESULTS RT-PCR analysis revealed that HuR, IAP1, IAP2 mRNA expression were accordingly 3.3-fold, 5.5-fold and 8.4 higher in the PDAC when compared to normal pancreas(P < 0.05). Expression of IAP1 was positively strongly correlated with HuR expression(P < 0.05, r = 0.783). Western blot analysis confirmed RTPCR results. High IAP1 expression, tumor resection status, T stage, lymph-node metastases, tumor differentiation grade, perineural and lymphatic invasion were identified as significant factors for shorter survival in PDAC patients(P < 0.05).Immunohistological analysis showed that HuR was mainly expressed in the ductal cancer cell's nucleus and less so in cytoplasm. RNA immunoprecipitation analysis confirmed IAP1 and IAP2 post-transcriptional regulation by HuR protein. Following siHuR transfection, IAP1 mRNA and protein levels were decreased, however IAP2 expression levels were increased.CONCLUSION HuR mediated overexpression of IAP1 significantly correlates with poor outcomes and early progression of pancreatic cancer. Further studies are needed to assess the underlying mechanisms.

Expression of second mitochondria-derived activator of caspases, X-linked inhibitor of apoptosis protein, and caspase-3 in pituitary adenomas

Studies concerning correlations between pituitary adenomas and cell apoptosis have mainly focused on upstream apoptosis signaling, but seldom on downstream mediators. In the present study, second mitochondria-derived activator of caspases （Smac）, X-linked inhibitor of apoptosis protein （XIAP）, and caspase-3 protein were qualitatively analyzed using immunohistochemistry, and quantified by western blot. Smac, XIAP, and caspase-3 mRNA expressions were detected by reverse transcription-PCR. Results showed that XIAP protein and mRNA expressions were greater in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. However, Smac and caspase-3 protein and mRNA expressions were lower in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. In the invasive pituitary adenomas, Smac expression was positively correlated with caspase-3 protein and mRNA expression （Protein： r = 0.55, P 0.01; mRNA： r = 0.50, P 0.01）. Smac and caspase-3 expressions were negatively correlated with XIAP protein and mRNA expression （Protein： r = -0.56, -0.64, P 0.01; mRNA： r = -0.69, -0.67, P 0.01）. However, no significant differences in correlation among Smac, XIAP, and caspase-3 were detectable in noninvasive pituitary adenomas. These data indicated that high expression of XIAP and low expression of Smac and caspase-3 suppressed cell apoptosis and led to enhanced invasiveness of pituitary adenomas. Thus, Smac, XIAP, and caspase-3 may be useful markers in determining the invasive behavior of pituitary adenomas.

Regulatory Effects of X-linked Inhibitor of Apoptosis Protein and Pro-apoptotic Protein Smac on Apoptosis Resistance to Chemotherapy in Pancreatic Cancer Cells~*

Objective： To investigate the relation of X-linked inhibitor of apoptosis （XIAP） and second mitochondria-derived activator of caspase （Smac） signaling pathway to chemoresistance in human pancreatic cancer Panc-1 and BXPC-3 cells. Methods： Apoptosis and the changes of XIAP expression in permeabilized cells induced by cisplatin and 5-fluorouracil （FU） were measured by flow cytometry. The cytosolic expression of XIAP, Smac and caspase-3 was detected by Western blot. A recombinant plasmid vector pEGFP-N1/Smac was constructed and transfected into of Pancol cells. The effect of cytosolic overexpression of Smac on apoptosis of Panc-1 cells was evaluated by flow cytometry. Results： Panc-1 was more resistant to cisplatin or 5-FU induced apoptosis than BXPC-3. Western blot revealed that chemoresistant Panc-1 highly expressed XIAP, and increased cytosolic expression of Smac might be responsible for the marked down-regulation of XIAP in chemo-sensitive BXPC-3 cells after exposure to cisplatin or 5-FU. Furthermore, cytosolic overexpression of Smac could significantly down-regulate the levels of XIAP and promote the activity of caspase-3, as well as sensitize Panc-1 cells to anticancer drug-induced apoptosis. Conclusion： Anticancer drug-induced apoptosis requires mitochondrial release of Smac and downregulation of XIAP, which may be an important determinant of chemo-sensitivity in pancreatic cancer cells. Up-regulation of cytosolic expression of Smac may act as an effective modifying signal to overcome apoptosis resistance to chemotherapy in pancreatic cancer cells.

Targeting X-linked inhibitor of apoptosis protein inhibits pancreatic cancer cell growth through p-Akt depletion

AIM: To determine whether lentivirus-mediated shRNA targeting the X-linked inhibitor of apoptosis protein (XIAP) gene could be exploited in the treatment of pancreatic cancer. METHODS: Human pancreatic cancer cells Panc-1, Mia-paca2, Bxpc-3 and SW1990, infected with lentivirus, were analyzed by real-time polymerase chain reaction (PCR). Western blotting was used to examine XIAP protein levels, survivin and p-Akt to confirm the result of real-time PCR and determine the possible mechanism. The 3-(4,5-cimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay was used to measure IC50 to determine chemosensitivity to the chemotherapeutic drugs 5-fluorouracil (5-FU) and gemcitabine. A colony assay, MTT assay and a tumorigenicity experiment were used to study cell proliferation in vitro and in vivo . Caspase-3/7 activity, 4',6-diamidino-2-phenylindole-staining and flow cytometric measurements were used to study apoptosis in SW1990 cells. RESULTS: XIAP proteins were found to be differen- tially expressed among pancreatic cancer cell lines Panc-1, Mia-paca2, Bxpc-3 and SW1990. Data of real-time PCR and Western blotting showed that XIAP was reduced persistently and markedly by lentivirus-mediated shRNA. Downregulation of XIAP by transfection with XIAP shRNA resulted in decreased p-Akt expression. XIAP shRNA also inhibited the growth of pancreatic cancer cells in vitro and in vivo , enhanced drug-induced apoptosis and increased chemosensitivity to 5-FU and gemcitabine. Results also suggest that inhibition of XIAP and subsequent p-Akt depletion may have an anti-tumor effect through attenuating the ability of cancer cells to survive. CONCLUSION: Lentivirus-mediated gene therapy is an attractive strategy in the treatment of pancreatic cancer and justifies the use of lentivirus in pancreatic cancer gene therapy studies.

Baculoviral inhibitor of apoptosis protein repeatcontaining protein 3 delays early Wallerian degeneration after sciatic nerve injury

Wallerian degeneration is a complex biological process that occurs after nerve injury,and involves nerve degeneration and regeneration.Schwann cells play a crucial role in the cellular and molecular events of Wallerian degeneration of the peripheral nervous system.However,Wallerian degeneration regulating nerve injury and repair remains largely unknown,especially the early response.We have previously reported some key regulators of Wallerian degeneration after sciatic nerve injury.Baculoviral inhibitor of apoptosis protein repeat-containing protein 3(BIRC3)is an important factor that regulates apoptosis-inhibiting protein.In this study,we established rat models of right sciatic nerve injury.In vitro Schwann cell models were also established and subjected to gene transfection to inhibit and overexpress BIRC3.The data indicated that BIRC3 expression was significantly up-regulated after sciatic nerve injury.Both BIRC3 upregulation and downregulation affected the migration,proliferation and apoptosis of Schwan cells and affected the expression of related factors through activating c-fos and ERK signal pathway.Inhibition of BIRC3 delayed early Wallerian degeneration through inhibiting the apoptosis of Schwann cells after sciatic nerve injury.These findings suggest that BIRC3 plays an important role in peripheral nerve injury repair and regeneration.The study was approved by the Institutional Animal Care and Use Committee of Nantong University,China(approval No.2019-nsfc004)on March 1,2019.

Expression of X-linked Inhibitor of Apoptosis Protein and Its Effect on Chemotherapeutic Sensitivity of Bladder Carcinoma

The expression of X-linked inhibitor of apoptosis protein (XIAP) gene and its effect on chemotherapeutic sensitivity in bladder carcinoma was explored. By using immunohistochemistry, the expression of XIAP was detected in 47 bladder carcinomas and 5 normal bladder tissues. The XIAP gene was transfected into bladder cancer cell line T24 by liposome and the positive clone was screened by G418. Cellular XIAP mRNA level was detected by RT-PCR. Low-dose mitocycin C was administered to induce the apoptosis of T24 cells. The in vitro growth of bladder carcinoma cells was analyzed by MTT colorimetry, and the apoptosis rate was assayed by TUNEL methods. It was found XIAP was moderately expressed in bladder carcinomas with the the positive rate being 78.73% (37/47), but the positive rate was not correlated with carcinoma stages and grades (P<0.05). XIAP mRNA level in transfected T24 cells was significantly increased by 3.8 times as compared with that in the cells not transfected with XIAP. After treatment with low-dose mitomycin C (0.005 and 0.05 mg/mL), the growth rate in XIAP no-transfected control group was increased by (11.60±0.25)% and (16.51±0.87)% (P<0.05), and the apoptosis rate was decreased by (10.1±0.2)% and (11.9±0.2%) (P<0.05) respectively as compared with XIAP transfected group. It was concluded that XIAP was expressed in most of bladder carcimoma samples. Overexpression of XIAP in T24 could significantly reduce the MMC-induced apoptosis of bladder carcinoma, suggesting its effect on the chemothera- peutic sensitivity of T24 cells.

肝外胆管癌ANXA1和XIAP表达的临床病理研究

目的探讨膜联蛋白A1(ANXA1)和X连锁凋亡抑制蛋白(XIAP)表达与肝外胆管癌临床病理特征及预后的关系。方法58例肝外胆管癌手术切除标本及30例癌旁胆管组织,应用EliVision^(TM)plus免疫组织化学染色二步法检测ANXA1和XIAP在癌组织及癌旁胆管组织中的表达,分析ANXA1和XIAP与肝外胆管癌患者性别、年龄、癌灶大小、分化等级、TNM分期、浸润转移及3年生存率7项临床病理特征的相关性。结果癌组织ANXA1和XIAP阳性率分别为84.5%(49/58)和81.0%(47/58),癌旁胆管组织分别为30.0%(9/30)和26.7%(8/30),差异有统计学意义(均P<0.05)。ANXA1表达与性别、年龄、分化等级无关(均P>0.05),在癌灶>1.5 cm、TNM(Ⅲ+Ⅳ)期、有浸润转移和3年内死亡患者中,其阳性率显著高于癌灶≤1.5 cm、TNM(Ⅰ+Ⅱ)期、无浸润转移和3年内生存患者(均P<0.05);XIAP表达与性别、年龄无关(均P>0.05),在癌灶>1.5 cm、低分化、TNM(Ⅲ+Ⅳ)期、有浸润转移和3年内死亡患者中,其阳性率显著高于癌灶≤1.5 cm、(高+中)分化、TNM(Ⅰ+Ⅱ)期、无浸润转移和3年内生存患者(均P<0.05)。ANXA1和XIAP表达呈正相关性(r=0.54)。结论ANXA1和XIAP与肝外胆管癌发生发展显著相关,两者表达上调预示癌灶大、分期晚、易浸润转移、生存期短。

抑制miR-130a表达对SACC-83顺铂化疗敏感性及XIAP MDR1蛋白表达的影响

目的研究抑制miR-130a表达对人涎腺腺样囊性癌细胞株(SACC-83)顺铂(DDP)化疗敏感性及X染色体连锁凋亡抑制蛋白(XIAP)、多药耐药基因(MDR1)表达的影响。方法构建人涎腺腺样囊性癌DDP耐药细胞株(SACC-83/DDP),采用实时荧光定量(qRT-PCR)检测SACC-83、SACC-83/DDP细胞中miR-130a表达水平;将SACC-83/DDP细胞随机分为对照组、mir-130a inhibitor组(转染mir-130a inhibitor)、DDP+mir-130a inhibitor阴性对照组(30μmol/L DDP+转染mir-130a inhibitor阴性对照)及DDP+mir-130a inhibitor组(30μmol/L DDP+转染mir-130a inhibitor),采用CCK-8法测定各组细胞生存率以及对DDP的耐药性,流式细胞术检测细胞凋亡率,TUNEL染色检测细胞凋亡指数;qRT-PCR检测细胞miR-130a、XIAP、MDR1、PTEN mRNA水平,免疫印记法检测细胞XIAP、MDR1、PTEN蛋白表达。结果与SACC-83细胞相比,miR-130a在SACC-83/DDP细胞中高表达(P<0.05);与对照组和mir-130a inhibitor组相比,DDP+mir-130a inhibitor组细胞生存率降低,凋亡率和凋亡指数升高(P<0.05);与mir-130a inhibitor组相比,DDP+mir-130a inhibitor组细胞生存率降低,凋亡率和凋亡指数升高(P<0.05);与对照组相比,mir-130a inhibitor组、DDP+mir-130a inhibitor组细胞miR-130a水平、XIAP mRNA及蛋白、MDR1 mRNA及蛋白表达降低(P<0.05),凋亡率、凋亡指数和PTEN蛋白表达升高(P<0.05);与DPP+mir-130a inhibitor组相比,DDP+mir-130a inhibitor阴性对照组细胞miR-130a水平、XIAP mRNA及蛋白、MDR1 mRNA及蛋白表达升高(P<0.05),凋亡率、凋亡指数和PTEN蛋白表达下降(P<0.05);SACC-83/DDP细胞对DDP的耐药性明显高于SACC-83细胞,抑制miR-130a表达逆转了SACC-83/DDP细胞的DDP耐药性。结论抑制miR-130a表达,可能下调XIAP表达,增强人涎腺腺样囊性癌细胞株对顺铂化疗的敏感性。

Effect of Nimesulide on proliferation and apoptosis of human hepatoma SMMC-7721 cells

AIM: Cyclooxygenase-2 (COX-2) has been suggested to be associated with carcinogenesis. We sought to investigate the effect of the selective COX-2 inhibitor, Nimesulide on proliferation and apoptosis of SMMC-7721 human hepatoma cells.METHODS: This study was carried out on the culture of hepatic carcinoma SMMC-7721 cell line. Various concentrations of Nimesulide (0, 200 micromol/L, 300 micromol/L, 400 micromol/L) were added and incubated. Cell proliferation was detected with MTT colorimetric assay, cell apoptosis by electron microscopy, flow cytometry and TUNEL.RESULTS: Nimesulide could significantly inhibit SMMC-7721 cells proliferation dose-dependent and in a dependent manner compared with that of the control group. The duration lowest inhibition rate produced by Nimesulide in SMMC-7721 cells was 19.06%, the highest inhibition rate was 58.49%. After incubation with Nimesulide for 72 h, the most highest apoptosis rate and apoptosis index of SMMC-7721 cells comparing with those of the control were 21.20%+/-1.62% vs 2.24%+/-0.26% and 21.23+/-1.78 vs 2.01+/-0.23 (P【0.05). CONCLUSION:The selective COX-2 inhibitor, Nimesulide can inhibit the proliferation of SMMC-7721 cells and increase apoptosis rate and apoptosis index of SMMC-7721 cells. The apoptosis rate and the apoptosis index are dose-dependent. Under electron microscope SMMC-7721 cells incubated with 300 micromol and 400 micromol Nimesulide show apoptotic characteristics. With the clarification of the mechanism of selective COX-2 inhibitors, These COX-2 selective inhibitors can become the choice of prevention and treatment of cancers.

JTE-522-induced apoptosis in human gastric adenocarinoma cell line AGS cells by caspase activation accompanying cytochrome C release,membrane translocation of Bax and loss of mitochondrial membrane potential

AIM: To investigate the role of the mitochondrial pathway in JTE-522-induced apoptosis and to investigate the relationship between cytochrome C release, caspase activity and loss of mitochondrial membrane potential (Deltapsim). METHODS: Cell culture, cell counting, ELISA assay, TUNEL, flow cytometry, Western blot and fluorometric assay were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanism. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Caspases 8 and 9 were activated during apoptosis as judged by the appearance of cleavage products from procaspase and the caspase activities to cleave specific fluorogenic substrates. To elucidate whether the activation of caspases 8 and 9 was required for the apoptosis induction, we examined the effect of caspase-specific inhibitors on apoptosis. The results showed that caspase inhibitors significantly inhibited the apoptosis induced by JTE-522. In addition, the membrane translocation of Bax and cytosolic release of cytochrome C accompanying with the decrease of the uptake of Rhodamin 123, were detected at an early stage of apoptosis. Furthermore, Bax translocation, cytochrome C release, and caspase 9 activation were blocked by Z-VAD.fmk and Z-IETD-CHO. CONCLUSION: The present data indicate a crucial association between activation of caspases 8, 9, cytochrome C release, membrane translocation of Bax, loss of Deltapsim and JTE-522-induced apoptosis in AGS cells.

The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes

We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis.

MG132 Induced Apoptosis Pathway in HL-60 Cells and Impact of Allogeneic Mixed Lymphocyte Reaction

Objective： To investigate the proteasome inhibitor MG132-induced apoptosis pathway in HL-60 cells and the role of allogeneic mixed lymphocyte reaction. Methods： Cell apoptosis was analyzed by flow cytometry. The expressions of p21 protein, p27 protein and p53 protein in HL-60 ceils treated with MG132 were measured by Western blot. The proliferation of, peripheral blood mononuclear cells （PBMNCs） after treatment with 75 Gy irradiated HL-60 cells treated with MG132 was measured with CCK-8. Results： High-dose MG132 induced apoptosis in HL-60 cells. No significant change was observed in MG132-induced apoptosis after inhibiting caspase-8 and caspase-9 pathway. The expressions of p21 protein and p27 protein increased in MG132-induced apoptosis. HL-60 cells treated with low-dose MG132 improved the proliferation of PBMNCs from healthy volunteers. Conclusion： High-dose MG132 induced apoptosis and directly killed HL-60 ceils. MG132 induced apoptosis in a caspase-8- and caspase-9-independent pathway, p21 protein and p27 protein were involved in MG132-induced apoptosis in HL-60 cells. HL-60 cells treated with Low-dose MG132 improved the effect of promoting the proliferation of PBMNCs from healthy volunteers.

XAF1 mediates apoptosis through an extracellular signal-regulated kinase pathway in colon cancer

Background:XIAP-associated factor 1(XAF1)negatively regulates the function of the X-linked inhibitor of apoptosis protein(XIAP),a member of the IAP family that exerts antiapoptotic effects.The extracellular signal-regulated kinase(ERK)pathway is thought to increase cell proliferation and to protect cells from apoptosis.The aim of the study was to investigate the correlation between the ERK1/2 signaling pathway and XAF1 in colon cancer.Methods:Four human colon cancer cell lines,HCT1116 and Lovo(wildtype p53),DLD1 and SW1116(mutant p53),were used.Lovo stable transfectants with XAF1 sense and antisense were established.The effects of dominant-negative MEK1(DN-MEK1)and MEK-specific inhibitor U0126 on the ERK signaling pathway and expression of XAF1 and XIAP proteins were determined.The transcription activity of core XAF1 promoter was assessed by dual luciferase reporter assay.Cell proliferation was measured by MTT assay.Apoptosis was determined by Hoechst 33258 staining.Results:U0126 increased the expression of XAF1 in a time-and dose-dependent manner.A similar result was obtained in cells transfected with DN-MEK1 treatment.Conversely,the expression of XIAP was down-regulated.Activity of the putative promoter of the XAF1 gene was significantly increased by U0126 treatment and DN-MEK1 transient transfection.rhEGF-stimulated phosphorylation of ERK appeared to have little or no effect on XAF1 expression.Overexpression of XAF1 was more sensitive to U0126-induced apoptosis,whereas down-regulation of XAF1 by antisense reversed U0126-induced inhibition of cell proliferation.Conclusions:XAF1 expression was up-regulated by inhibition of the ERK1/2 pathway through transcriptional regulation,which required de novo protein synthesis.The results suggest that XAF1 mediates apoptosis induced by the ERK1/2 pathway in colon cancer.

口腔腺样囊性癌患者血清miR-24、XIAP mRNA表达及其与预后的相关性

目的探讨口腔腺样囊性癌(ACC)患者血清miR-24、X染色体连锁凋亡抑制蛋白(XIAP)mRNA表达情况,及其与患者预后的关系。方法选取2010年6月—2016年2月张家口市第一医院口腔ACC患者60例(口腔ACC组),以60名体检健康者作为正常对照组。收集所有研究对象的血清样本和ACC患者的癌组织、癌旁组织(距肿瘤组织边缘≥5 cm)样本,以及临床资料。检测血清和组织中miR-24、XIAP mRNA的相对表达量。采用Pearson相关分析评估miR-24与XIAP的相关性。对ACC患者进行随访。采用Kaplan-Meier生存曲线和Log-rankχ2检验分析血清miR-24、XIAP相对表达量与口腔ACC患者预后的关系。采用Cox回归分析评估影响口腔ACC患者预后的危险因素。结果与正常对照组比较,口腔ACC组血清miR-24相对表达量显著降低(P<0.05),XIAP mRNA相对表达量显著升高(P<0.05)。与癌旁组织比较,癌组织miR-24相对表达量显著降低(P<0.05),XIAP mRNA相对表达量显著升高(P<0.05)。口腔ACC患者血清miR-24与XIAP mRNA呈负相关(r=-0.486,P<0.05)。分别以口腔ACC患者血清miR-24和XIAP mRNA相对表达量的均值作为临界值,分为高表达组和低表达组。miR-24低表达组、XIAP mRNA高表达组神经侵袭和淋巴转移患者例数分别显著多于miR-24高表达组、XIAP mRNA低表达组(P<0.05)。Kaplan-Meier生存曲线分析结果显示,miR-24低表达组、XIAP mRNA高表达组累积生存率分别显著低于miR-24高表达组、XIAP mRNA低表达组(Log-rankχ2值分别为7.212、8.568,P值分别为0.007、0.003)。Cox回归分析结果显示,有神经侵袭、XIAP mRNA高表达是口腔ACC患者预后不良的独立危险因素(P<0.05),miR-24高表达是口腔ACC患者预后的独立保护因素(P<0.05)。结论口腔ACC患者血清miR-24和XIAP表达均与预后相关,或可作为新的口腔ACC预后评估生物标志物。

急性胰腺炎小鼠胰腺和远隔脏器组织TRAF6、XIAP表达变化及其与细胞凋亡的关系

目的观察急性胰腺炎小鼠胰腺和远隔脏器组织中肿瘤坏死因子受体相关因子6(TRAF6)和X连锁凋亡抑制蛋白(XIAP)表达变化,并分析其与多脏器细胞凋亡的关系。方法将30只雄性C57BL/10SnJ小鼠随机分为对照组、急性水肿性胰腺炎(AEP)组、急性坏死性胰腺炎(ANP)组,每组10只。AEP组建立AEP模型,ANP组建立ANP模型,对照组注射等量磷酸盐缓冲盐水。采用RT-qPCR法检测各组胰腺组织中的TRAF6、XIAP mRNA,Western blotting法检各组胰腺、肠、肝、肺、肾组织中的cleaved Caspase-3、TRAF6、XIAP蛋白。采用TUNEL法测算胰腺、小肠、肝、肺、肾组织细胞凋亡率。结果ANP组、AEP组胰腺及多个远隔脏器组织中TRAF6、XIAP蛋白表达与对照组比较差异均有统计学意义(P均<0.05);AEP组胰腺组织中XIAP mRNA表达低于ANP组(P<0.05);AEP组胰腺、肠、肝、肺、肾组织中TRAF6蛋白表达高于ANP组,XIAP蛋白表达低于ANP组(P均<0.05)。AEP组胰腺、肠、肝、肺、肾组织细胞凋亡率及cleaved Caspase-3表达高于ANP组和对照组(P均<0.05)。胰腺炎小鼠胰腺及多个远隔脏器组织中cleaved Caspase-3蛋白表达与TRAF6蛋白表达呈正相关,与XIAP蛋白表达呈负相关(P均<0.05)。结论急性胰腺炎小鼠胰腺和远隔脏器组织中TRAF6、XIAP表达异常,且与细胞凋亡指标存在相关性;TRAF6、XIAP在AEP与ANP中的表达趋势有所差异,TRAF6、XIAP对细胞凋亡的调控作用可能与急性胰腺炎严重程度有关。

微小RNA-103a-3p通过肿瘤蛋白53调控凋亡抑制剂1/P53对骨质疏松症的影响

目的探讨微小RNA(miR)-103a-3p调控细胞肿瘤蛋白53调控凋亡抑制剂1(TRIAP1)对成骨细胞分化以及去卵巢小鼠骨量的影响。方法MC3T3-E1细胞分为正常对照(NC)组、miR-103a-3p-NC组、miR-103a-3p模拟(mimc)组、miR-103a-3p mimic+TRIAP1-NC组、miR-103a-3p mimic+TRIAP1 mimic组。Real-time PCR检测细胞miR-103a-3p、TRIAP1、P53的mRNA表达,MTT法和流式细胞术检测细胞增殖及凋亡,免疫荧光染色和茜红素染色检测细胞骨架F-actin表达和矿化情况,ELISA检测细胞碱性磷酸酶(ALP)活性。24只雌性小鼠设为sham组、骨质疏松症(OP)组、miR-103a-3p antagonist-NC组和miR-103a-3p antagonist组,每组6只摘取双侧卵巢制备OP模型,sham组仅分离卵巢组织周围脂肪。测定骨组织miR-103a-3p、TRIAP1、P53、ALP、骨钙素(OCN)、骨桥蛋白(OPN)的mRNA表达,microCT测定骨密度(BMD)、骨矿物质含量(BMC),HE染色观察骨组织病理改变。结果细胞转染miR-103a-3p mimic后,miR-103a-3p及P53表达升高、TRIAP1表达降低,细胞增殖降低、凋亡增加,F-actin表达减弱,钙结节数量减少,ALP活性降低(P<0.01);而在增加转染TRIAP1 mimic后,以上miR-103a-3p mimics导致的结果均得到显著逆转(P<0.01)。OP组小鼠骨组织miR-103a-3p、P53表达升高,TRIAP1、ALP、OCN、OPN基因表达降低,BMD、BMC降低,骨组织结构破坏(P<0.05);miR-103a-3p antagonist组小鼠骨组织miR-103a-3p及P53表达降低,TRIAP1、ALP、OCN、OPN基因表达升高,BMD、BMC升高,骨组织结构改善(P<0.05)。结论MiR-103a-3p可介导TRIAP1/P53抑制成骨细胞增殖及矿化,而miR-103a-3p拮抗治疗可减少OP小鼠骨量丢失。

急性病毒性坏死病毒IAP-86基因的克隆、表达及抗凋亡研究

在已经完成的栉孔扇贝急性病毒性坏死病毒(acute viral necrosis virus,AVNV)全基因组序列测序与分析的基础上,设计特异性引物,克隆得到了ORF86编码的杆状病毒凋亡抑制蛋白基因(IAP-86)。IAP-86基因与pET32a(+)质粒连接构建得到重组质粒pET32a-IAP86,将重组质粒转化到E.coil BL21(DE3)中,使用异丙基-β-D-硫代半乳糖苷(IPTG)诱导蛋白表达,SDS-PAGE检测显示表达蛋白分子量约为40 ku,经Western-blotting和质谱分析证明,该蛋白即为IAP-86融合蛋白,Co2+柱纯化后得到了纯化的IAP-86融合蛋白。将重组的IAP-86蛋白用FITC标记,荧光显微镜下观察,发现重组的IAP-86蛋白最终能够与栉孔扇贝血淋巴细胞的细胞核和细胞质结合。细胞凋亡检测实验发现,重组的IAP-86蛋白能够在一定程度上抑制栉孔扇贝血淋巴细胞凋亡,凋亡抑制率为7%。本实验应用原核表达成功得到了IAP-86蛋白,并证明IAP-86对栉孔扇贝细胞的凋亡有一定抑制作用,这为进一步研究AVNV的侵染机制提供依据。

凋亡抑制蛋白(IAP):抗癌新靶点

凋亡抑制蛋白 (IAP)能够抑制细胞内凋亡作用 ,是与肿瘤发生、发展密切相关的关键分子。近年来 ,以IAP为靶点研制有基因特异性的拮抗剂 ,寻找高效低毒的基因治疗策略倍受关注。IAP家族中survivin及livin特异表达于肿瘤组织的特性以及IAP抑制剂Smac的发现 ,为肿瘤治疗提供了新的发展方向。