An in vitro study to explore the role of prolylcarboxypeptidase in non-small cell lung cancer

Prolylcarboxypeptidase (PRCP) belongs to the S28 family of proteases, which is also a dipeptidyl peptidase.In this study, we demonstrate the expression pattern of PRCP in Non-small cell lung cancer (NSCLC). We found thatthe repression of PRCP expression by small interfering RNA successfully inhibited cell proliferation, migration, andinvasion. Further, we explored the involvement of PRCP in the regulation of epithelial-mesenchymal transition (EMT).The epithelial marker E-cadherin was significantly increased, meanwhile mesenchymal markers MUC1, vimentin, andSNAIL were markedly decreased in PRCP knockdown cells. Moreover, the downregulation of PRCP in the NSCLCcells induced the expression of apoptosis-related proteins in vitro. We performed RT-PCR in 30 pairs of clinical NSCLCtissues and adjacent non-cancerous tissues, which revealed significantly higher PRCP expression levels in cancer tissuesthan in adjacent non-cancerous tissues. Collectively the results from our study suggest a possible cancer promotion roleof PRCP in NSCLC.     

Apoptosis in immune cells induced by fission fragment ^147Pm

Apoptosis in human acute lymphoblastic leukemia cell line Molt-4 cell and macrophage cell line Ana-1 cell could be induced by fission fragment 147Pm,The cumulative absorption dose of ^147Pm in cultural cells through different periods were estimated.By using fluorescence microscopy and microautoradiographic tracing it can be found that Molt-4 and Anal-1 cells internally irradiated by ^147Pm,displayed an obvious nuclear fragmentation and a marked phknosis in immune cell nucei,as well as DNA chain fragmentation and apoptotic bodies formation.The microautoradiographic study showed that ^147Pm could infiltrate thourgh cell membrane and displayed membrane-seeking condensation in cells.At the same time.the membrane-bounded apoptotic bodies were observed.Experimental results in recent study provide evidence that Molt-4 and Ano-1 immune cells undergo apoptosis while internally irradiated with ^147Pm.     

p53和Bcl—2／Bax在辐射诱导胸腺细胞凋亡中的作用

采用流式细胞术对昆明小鼠接受７５ｍＧｙ和２ＧｙＸ射线全身照射后，胸腺细胞内细胞凋亡相关基因ｐ５３，Ｂｃｌ－２和Ｂａｘ蛋白的表达进行了比较研究。结果表明，７５ｍＧｙＸ射线全身照射后２４ｈ，ｐ５３基因蛋白产物的表达显著降低，而２ＧｙＸ射线全身照射后２４ｈ，ｐ５３基因蛋白表达则显著增高。     

禽流感病毒NS1A蛋白诱导人肺癌细胞SPC-A1的凋亡

目的研究禽流感病毒NS1A蛋白对人肺癌细胞SPC-A1增殖的影响。方法将含有NS1A基因的重组质粒pVAX1-NS1A经脂质体介导转染人肺癌细胞SPC-A1,用MTT检测其对细胞增殖的抑制作用;Annexin VFITC-PI结合流式细胞仪检测细胞凋亡率;PI结合流式细胞仪检测细胞周期的变化;对转染细胞的表达产物进行Western blot分析。结果NS1A蛋白能抑制人肺癌细胞SPC-A1增殖且呈时间依赖性。随着作用时间延长,重组质粒转染组细胞凋亡率可达38.17%,细胞周期中G0/G1比例升高,G1期阻滞。Western blot分析显示,重组质粒转染组细胞在相对分子质量约30000处可见特异性反应条带,与NS1A蛋白产物大小相符。结论禽流感病毒NS1A蛋白能够抑制SPC-A1细胞增殖,并诱导SPC-A1细胞凋亡。     

The Signaling Cascades of Ginkgolide B-Induced Apoptosis in MCF-7 Breast Cancer Cells

Ginkgolide B, the major active component of Ginkgo biloba extracts, can both stimulate and inhibit apoptotic signaling. Here, we demonstrate that ginkgolide B can induce the production of reactive oxygen species in MCF-7 breast cancer cells, leading to an increase in the intracellular concentrations of cytoplasmic free Ca²⁺ and nitric oxide (NO), loss of mitochondrial membrane potential (MMP), activation of caspase-9 and -3, and increase the mRNA expression levels of p53 and p21, which are known to be involved in apoptotic signaling. In addition, prevention of ROS generation by pretreatment with N-acetyl cysteine (NAC) could effectively block intracellular Ca²⁺ concentrations increases and apoptosis in ginkgolide B-treated MCF-7 cells. Moreover, pretreatment with nitric oxide (NO) scavengers could inhibit ginkgolide B-induced MMP change and sequent apoptotic processes. Overall, our results signify that both ROS and NO played important roles in ginkgolide B-induced apoptosis of MCF-7 cells. Based on these study results, we propose a model for ginkgolide B-induced cell apoptosis signaling cascades in MCF-7 cells.     

腺苷对缺血再灌注后心肌的保护作用

目的研究腺苷对大鼠心肌细胞凋亡及核因子κB(NF-κB)表达的影响。方法制备对照组(C组)、缺血再灌注损伤组(I/R组)和缺血再灌注前腺苷治疗组(AD组)的大鼠模型。电镜、光镜下观察心肌结构变化,采用原位缺口末端标记法(TUNEL)检测心肌细胞凋亡,免疫组织化学方法检测心肌组织NF-κB表达。结果AD组大鼠心肌细胞凋亡数(2 645.0±326.0)及心肌组织中NF-κB的表达(32.21%±17.91%)明显低于I/R组(5 113.0±503.7和60.30%±10.36%),明显高于对照组(67.7±51.3和11.98%±3.65%)。结论腺苷具有明显降低大鼠缺血再灌注后心肌细胞凋亡的作用,可能与腺苷减轻缺血再灌注心肌组织过度表达NF-κB有关。     

凋亡相关蛋白Apr-2的融合表达及多克隆抗体的制备

目的　融合表达凋亡相关蛋白Apr 2 ,并用该融合蛋白制备多克隆抗体。方法　将凋亡相关蛋白Apr 2克隆入PGEX 4T 2原核表达载体 ,转化大肠杆菌 ,IPTG诱导重组蛋白GST Apr 2表达 ,用该融合蛋白免疫家兔制备多克隆抗体 ,经ELISA及Westernblot检测。结果　融合表达蛋白GST Apr 2主要以包涵体的形式存在 ,表达的融合蛋白占菌体总蛋白质的 4 0 %以上。抗体效价为 1∶5 0 0 0。结论　已成功地进行Apr 2的融合表达 ,并获得了该蛋白的多克隆抗体     

姜黄素诱导肺癌A549细胞凋亡

目的：研究姜黄素对A549细胞凋亡的诱导作用,并探讨其可能的分子机制。方法：姜黄素处理A549细胞后,MTT法于不同时间点检测A549细胞的增殖情况;姜黄素处理A549细胞48h后,流式细胞术（Flow CytoMetry,FCM）检测A549细胞的凋亡率;30μmol／L姜黄素处理A549细胞24h、48h、72h后,RT—PCR、Western—Blot检测A549细胞中P53、Bcl2、Bax和cagpase-3基因的表达水平。结果：姜黄素对肺癌A549细胞增殖的抑制作用具有显著的浓度-时间依赖关系,30μmol／L姜黄素可诱导A549细胞凋亡。30μmoL／L姜黄素作用A549细胞24h即可引起A549细胞中P53、Bax和Caspase-3表达水平的上调,48h后可引起Bcl2表达水平的下调,诱导A549细胞凋亡。结论：30μmol／L姜黄素可诱导A549细胞凋亡,其机制可能与促进P53、Bax和Caspase-3基因的表达,抑制Bcl2基因的表达有关。     

Constructing liposomal nanovesicles of ginseng extract against hydrogen peroxide-induced oxidative damage to L929 cells

In this study, a liposomal nanovesicle was applied as a nanocarrier of ginseng extract (GE) to enhance the intracellular antioxidant activity of GE. The optimal condition of preparing GE liposomal nanovesicle (GELN) was prepared by tagging with 3.0 mol% of polyethenyl glycol (PEG3.0) followed by homogenisation at 15,000 psi for 5 min to reduce its diameter to ∼150 nm. PEG3.0-GELN encapsulated the most ginsenosides (234.1 ± 13.9 mg/g) with a higher reducing power than GELNs tagged with lower amounts of PEG (0-1.5 mol%). After treatment with PEG3.0-GELN (20 μg ginsenoside/ml), the % increase in mitochondrial membrane potential (ΔΨ) of H₂O₂-damaged cells rose 20.9% and the % decrease in apoptosis increased 12.4%, compared with those treated with GE. Therefore, this investigation proved that utilising liposomal nanovesicles to encapsulate GE can effectively suppress the depolarisation of ΔΨ and thus enhance the survival rate of H₂O₂-damaged cells.