Human prostate cancer cell death by novel anticancer compounds, apoptosis-inducing nucleosides from CD57+ HLA-DR(bright) natural suppressor cell line

BACKGROUND: We validated the induction of apoptosis in human prostate cancer PC3 cells by apoptosis-inducing nucleosides (AINs) released from the CD57(+)HLA-DR(bright)-natural suppressor (57.DR-NS) cell line. We analyzed the molecular signaling pathway during AINs-induced apoptosis in PC3 cells. METHODS: Direct and indirect co-cultures between 57.DR-NS and PC3 cells were performed. AINs were isolated by high-performance liquid chromatography (HPLC) from 57.DR-NS cell cultures. Apoptosis in PC3 cells was analyzed by DNA fragmentation, sub-G(1) DNA content with flow cytometry, and terminal deoxynucleotide transferase-mediated dUTP nick end-labeling (TUNEL) method. The DNA strand breaks and activation of caspase-3 in PC3 cells were measured by DNA unwinding and flow cytometry assay. RESULTS: The 57.DR-NS cell line generated apoptosis in PC3 cells via AINs. AINs isolated from 57.DR-NS cell cultures induced apoptosis in PC3 cells. Furthermore, we found DNA strand breaks followed by activation of caspase-3 during AINs-induced apoptosis in PC3 cells. CONCLUSIONS: The data obtained here indicated that AINs could induce apoptosis in PC3 cells through DNA strand breaks and activation of caspase-3.     

Effect of the XIAP inhibitor Embelin on TRAIL-induced apoptosis of pancreatic cancer cells

BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in a wide variety of tumor cells, while it has no toxicity for the majority of normal cells.Therefore, TRAIL may be a suitable agent for anticancer therapy. We previously reported that a number of pancreatic cancer cell lines show resistance to TRAIL-induced apoptosis via overexpression of XIAP and FLIP. The present study was conducted to further examine TRAIL-based therapeutic strategies by aiming to restore functional apoptotic pathways in resistant pancreatic cancer cells. METHODS: In various pancreatic cancer cell lines, TRAIL-induced apoptosis was evaluated in the presence or absence of an XIAP-inhibitor (Smac peptide). Second, TRAIL-induced apoptosis was evaluated in TRAIL-resistant AsPC-1 cells with or without FLIP antisense. Third, the combined effect of Smac peptide and FLIP antisense was tested, and the activation of apoptosis-related caspases and poly (ADP-ribose) polymerase was evaluated. Finally, TRAIL-induced apoptosis was evaluated in the presence or absence of FLIP antisense and an XIAP inhibitor (embelin). RESULTS: Smac peptide enhanced TRAIL-induced apoptosis in a dose-dependent manner for several pancreatic cancer cell lines, but showed no effect on TRAIL-resistant AsPC-1 cells. Smac peptide alone had no influence on cell viability. TRAIL-induced apoptosis was restored in TRAIL-resistant AsPC-1 cells by exposure to FLIP antisense, which suppressed the expression of FLIP. The effect of TRAIL was augmented by the combination of FLIP antisense and Smac peptide. Similarly, TRAIL-induced apoptosis was restored by the combination of FLIP antisense and embelin. Activation of apoptotic caspases and cleavage of poly (ADP-ribose) polymerase was observed after sensitization of TRAIL-resistant pancreatic cancer cells. CONCLUSIONS: Pancreatic cancer cells gain resistance to TRAIL-induced apoptosis via expression of the antiapoptotic proteins XIAP and FLIP. Smac peptide and FLIP antisense could restore the apoptotic effect of TRAIL. An XIAP inhibitor, embelin, enhanced the effect of TRAIL in the presence of FLIP antisense. These findings may provide useful information for the development of TRAIL-based therapeutic strategies by restoring functional apoptotic pathways in resistant pancreatic cancer cells. In addition, a low molecular weight XIAP inhibitor like embelin could be a lead compound for the development of effective XIAP inhibitors.     

含胱天蛋白酶富集功能域凋亡抑制因子在心血管疾病中的研究进展

细胞凋亡在维持机体正常发育以及内环境稳定中发挥重要作用,同时也对多种疾病的病理生理产生影响。研究表明心肌细胞凋亡参与了多种心血管疾病的发生发展过程。含胱天蛋白酶富集功能域凋亡抑制因子(ARC)是迄今为止唯一在心脏特异性高表达的抗凋亡蛋白,并可通过其抗凋亡能力发挥心肌保护作用。本文就ARC的结构和特点、ARC在心血管疾病中的作用及机制予以综述。     

III期结直肠癌中NLRC3与预后和肿瘤免疫的关系

目的：探讨核苷酸寡聚化结构域样受体家族半胱天冬酶募集结构域蛋白3(nucleotide binding oligomerization domain-like receptor family caspase recruitment domain containing 3,NLRC3)与III期结直肠癌的预后及肿瘤免疫相关指标 的关系。方法：回顾性收集中南大学湘雅医院2012年至2013年122例经手术根治切除的III期结直肠癌患者的相关资 料。利用免疫组织化学法分析NLRC3与CD8+ T细胞的表达情况,利用患者的术前临床资料计算中性粒细胞/淋巴细 胞比值(neutrophil to lymphocyte ratio,NLR),并检测其微卫星稳定性。采用χ2检验分析NLRC3与临床病理因素之间的 关系,采用COX回归模型分析III期结直肠癌的独立预后因素。结果：在III期结直肠癌中,肿瘤组织CD8+ T细胞浸润 分期(χ2=27.79,P<0.01)、NLR值(χ2=6.35,P<0.05)、淋巴结转移分期(χ2=10.12,P<0.01)以及微卫星稳定性(χ2=6.05, P<0.05)与NLRC3的表达有关。NLRC3(OR=0.066,95% CI：0.020~0.218)、血管癌栓(OR=3.119,95% CI：1.547~6.286) 及NLR(OR=5.103,95% CI：2.465~10.563)对III期结直肠癌的5年总生存期(overall survival,OS)有影响(均P<0.05);另 外,NLRC3(OR=0.144,95% CI：0.055-0.377)、血管癌栓(OR=3.589,95% CI：1.859~6.932)及NLR(OR=2.939,95% CI： 1.509~5.723)对III期结直肠癌的无病生存期(disease free survival,DFS)同样有影响(均P<0.05)。结论：NLRC3,血管癌栓 和NLR是III期结直肠癌的独立预后因素。NLRC3通过抑制系统性炎症、促进局部抗肿瘤免疫而使III期结直肠癌患者 具有良好的预后。     

线粒体介导的凋亡途径与浅低温脑保护效应

低温有明显的神经保护作用,但其确切的作用机制尚未阐明。凋亡参与了缺血性脑损伤,且加重损伤程度。线粒体在凋亡过程中的作用越来越受到重视,多种促和抗凋亡因素作用于线粒体,引发线粒体功能和生化方面的改变,决定细胞损伤后的命运。最近在体和离体实验证实,凋亡及凋亡过程中的相关基因表达变化与浅低温的保护作用密切相关。就低温对线粒体介导的细胞凋亡效应作一综述。     

白细胞介素-1β转化酶基因在脑缺血再灌注后的表达

为了解白细胞介素－1β转化酶（ICE）基因在脑缺血再灌注后的表达情况，利用沙土鼠全脑缺血再灌注模型研究ICE mRNA在缺血再灌注时的诱导情况和丹参作用前后ICE的蛋白表达情况。结果发现，脑缺血再灌注后1－4天均有ICE mRNA表达；胶质细胞中ICE的表达在缺血再灌注后1－4天逐渐增加；应用丹参预防性干预后ICE的表达明显受到抑制（P＜0．01）。提示ICE可能在脑组织因缺血再灌注而发生的凋亡过程中发挥间接调节作用。     

Novel quinolone CHM‐1 induces apoptosis and inhibits metastasis in a human osterogenic sarcoma cell line

Novel 2‐phenyl‐4‐quinolone compounds have potent cytotoxic effects on different human cancer cell lines. In this study, we examined anticancer activity and mechanisms of 20‐fluoro‐6,7‐methylenedioxy‐2‐phenyl‐4‐quinolone (CHM‐1) in human osterogenic sarcoma U‐2 OS cells. CHM‐1‐induced apoptosis was determined by flow cytometric analysis, DAPI staining, Comet assay, and caspase inhibitors. CHM‐1‐inhibited cell migration and invasion was assessed by a wound healing assay, gelatin zymography, and a Transwell assay. The mechanisms of CHM‐1 effects on apoptosis and metastasis signaling pathways were studied using Western blotting and gene expression. CHM‐1 induced G2/M arrest and apoptosis at an IC₅₀ (3 µM) in U‐2 OS cells and caspase‐3, ‐8, and ‐9 were activated. Caspase inhibitors increased cell viability after exposure to CHM‐1. CHM‐1‐induced apoptosis was associated with enhanced ROS generation, DNA damage, decreased ΔΨ_m levels, and promotion of mitochondrial cytochrome c release. CHM‐1 stimulated mRNA expression of caspase‐3, ‐8, and ‐9, AIF, and Endo G. In addition, CHM‐1 inhibited cell metastasis at a low concentration (<3 µM). CHM‐1 inhibited the cell metastasis through the inhibition of MMP‐2, ‐7, and ‐9. CHM‐1 also decreased the levels of MAPK signaling pathways before leading to the inhibition of MMPs. In summary, CHM‐1 is a potent inducer of apoptosis, which plays a role in the anticancer activity of CHM‐1. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1637–1644, 2009     

桥本甲状腺炎甲状腺组织TRAIL、Caspase-3的表达

目的 研究桥本甲状腺炎(HT)患者甲状腺组织中肿瘤坏死因子相关凋亡诱导配体(TRAIL)、天冬氨酸特异性半胱氨酸蛋白酶-3(caspase-3)的表达及其在HT发病和病理改变中的意义. 方法 采用S-P免疫组织化学方法检测26例HT(HT组)和12例正常甲状腺组织(对照组)中TRAIL、caspase-3的表达情况. 结果 (1)TRAIL、caspase-3在HT组呈高表达,多见于浸润淋巴细胞旁的甲状腺滤泡上皮细胞;而浸润的淋巴细胞TRAIL染色阴性,caspase-3染色呈弱阳性.(2)TRAIL的表达阳性率在HT组明显高于对照组(72.92%vs 41.67%,P＜0.05),前者滤泡上皮细胞的表达强度明显高于后者[(0.051±0.016)vs (0.016±0.010),P＜0.05].(3)caspase-3的表达阳性率在HT组明显高于对照组(92.31%vs 33.33%,P＜0.01),滤泡上皮细胞的表达强度明显高于对照组[(0.065±0.025)vs(0.022±0.008),P＜0.05].(4)TRAIL与caspase-3的表达程度呈正相关 (rs=0.631,P=0.001). 结论 TRAIL与caspase-3可能共同参与HT的病理演变过程,通过表达TRAIL激活caspase-3而诱导甲状腺滤泡细胞凋亡,损伤甲状腺组织.     

Caspase-3、XIAP在骨关节炎中的表达及意义

目的探讨Caspase-3、XIAP在骨关节炎软骨细胞中的表达及意义。方法用免疫组化SP法、原住末端标记技术（TUNEL）等检测Caspase-3、XIAP在22例骨关节炎患者关节软骨细胞中的表达和软骨细胞凋亡情况。结果在软骨细胞中Caspase-3的表达实验组阳性率高于对照组（P〈0．01）；实验组软骨细胞凋亡程度与XIAP的表达呈负相关（P〈0．05），与Caspase-3的表达呈正相关（P〈0．01）。结论Caspase-3、XIAP基因的表达与骨关节炎发生发展有密切关系。