非霍奇金淋巴瘤中细胞凋亡与细胞增殖的研究

目的了解非霍奇金淋巴瘤(NHL)中细胞凋亡与细胞增殖间的关系,探讨两者在NHL发生与发展中的作用.方法利用TdT介导的dUTP缺口末端标记(TUNEL)法和PCNA免疫组化技术原位检测60例NHL中的细胞凋亡和增殖水平,计算凋亡指数(AI)和增殖指数(PI).结果B细胞性NHL中,随着恶性度增高,AI和PI均增高(P＜0.05),T细胞性NHL中高度恶性组PI明显高于低度恶性组(P＜0.05),而AI在两组之间无显著性差异(P＞0.05).AI和PI呈显著正相关(r=0.704,P＜0.01).结论在NHL中细胞凋亡与增殖之间可能存在密切的联系,共同参与了NHL的发生和恶性进展.对细胞凋亡和增殖水平的检测可能有助于NHL恶性度及预后的判断.     

Cyclooxygenase-2 overexpression in MCF-10F human breast epithelial cells inhibits proliferation, apoptosis and differentiation, and causes partial transformation

To investigate the effects of cyclooxygenase-2 (COX-2) overexpression on breast cancer development, we stably transfected MCF-10F human breast epithelial cells with an expression vector containing human COX-2 cDNA oriented in the sense (10F-S) or antisense (10F-AS) direction. As expected, 10F-S cells expressed elevated levels of COX-2 protein, whereas this protein was undetectable in the 10F-AS cells. Prostaglandin E(2) production in these cells reflected COX-2 levels. The 10F-S cells had a significantly decreased rate of proliferation compared to 10F-AS or parental cells, and a delay in progression through the G(1) phase of the cell cycle. COX-2 overexpression also caused resistance to detachment-induced apoptosis (anoikis) as well as an inhibition of differentiation in cells cultured in Matrigel. Furthermore, after approximately 20 passages in culture, 10F-S cells developed fibroblast-like features, expressed vimentin, and formed foci of dense growth when cultured at confluence, suggesting that the cells were undergoing epithelial to mesenchymal transition (EMT). The 10F-S cells, however, were unable to grow in soft agar or form tumors in nude mice, suggesting that they were only partially transformed. Our observations suggest that COX-2 overexpression in human breast epithelial cells will predispose the mammary gland to carcinogenesis.     

Lidamycin induces apoptosis of B-cell lymphoma cells and inhibits xenograft growth in nude mice

OBJECTIVE To study the cytotoxicity of Lidamycin （LDM） and its induction of apoptosis in Raji and Daudi cells of B-cell lymphoma, and the inhibition of growth of the lymphoma Raji xenograft in nude mice. METHODS MTT assay was used to observe the inhibition by LDM on the proliferation of the Raji and Daudi ceils. Annexin V-FITC/PI double-stain, in combination with flow cytometry （FCM）, was used to determine the induction of apoptosis by LDM in Raji cells. The B-cell lymphoma Raji xenograft model in nude mice was set up to detect the in vivo antitumor activity of LDM. RESULTS LDM markedly inhibited the proliferation of the Raji and Daudi cells in vitro, with IC50 values of 7.13×10^-11 mol/L and 2.91×10^-10 mol/L, respectively. The apoptotic rates of Raji cells were respectively 77.98% and 67.63% at 0.5 nmol/L and 0.25 nmol/L of LDM, indicating an obvious induction of apoptosis in Raji cells. LDM inhibited the formation and growth of human B-cell lymphoma Raji xenograft in nude mice. The inhibition rates of tumor growth were respectively 74.9% and 65.2% in LDM at dosage group of 0.05 mg/kg and 0.025 mg/kg, suggesting an apparent prolongation of survival time in the nude mouse bearing lymphoma. CONCLUSION LDM can effectively induce apoptosis of the B-cell lymphoma cells and inhibit the xenograft growth in nude mice.     

NK/T细胞淋巴瘤细胞凋亡和细胞增殖特征及意义

Objective:The aim was to study the features and clinical significance of cell apoptosis and proliferation of NK/T cell lymphoma.Methods:TdT-mediated dUTP nick end labeling and immunohistochemical Streptavidin-peroxidase method were used to study cell apoptosis and the expression of proliferation cell nuclear antigen in 25 NK/T cell lymphoma and 10 reactive lymphoid tissues.Results:Apoptotic index(AI) and proliferative index(PI) averaged(1.92%±0.86%) and(41.48%±5.10%) respectively in the 25 NK/T cell lymphom...     

白藜芦醇对人皮肤T细胞淋巴瘤Hut-78细胞增殖和凋亡影响观察

目的：研究白藜芦醇对人皮肤T细胞淋巴瘤（cutaneous T cell lymphomas,CTCL）Hut78细胞株体外增殖和凋亡的影响,并初步探讨其作用机制。方法：用不同浓度的白藜芦醇（5、10和20μmol／L）作用于人皮肤CTCLHut-78细胞,24和48h后MTT检测白藜芦醇对细胞增殖的影响;TUNEL末端标记法和Annexin V—FITC双标记流式法检测白藜芦醇对细胞凋亡的影响。结果：经5、10和20μmol／L浓度的白藜芦醇处理24h后,细胞A值分别为1．202±0．094、0．568±0．019和0．535±0．033,与0μmol／LA值（1．272±1．107）比较,差异有统计学意义,P〈0．01。各浓度作用48h后,细胞A值分别为0．604±0．095、0．314±0．042和0．260±0．055,与0μmol／LA值（0．781±0．020）比较,差异有统计学意义,P〈0．01;与作用24h后同浓度A值比较,差异均有统计学意义,P〈0．01。随着时间和浓度的增加Hut-78细胞生长均受到不同程度的抑制,呈明显的浓度和时间依赖性。经5、lO和20／μmol／L浓度的白藜芦醇处理24h后,HUT-78细胞抑制率分别为（5．28±2．64）％、（53．52±10．86）％和（56．13±10．79）％,与0μmol／L抑制率（0）比较,差异均有统计学意义,P〈0．01;HUT-78细胞凋亡率分别为92．35％、96．39％和98．56％,与0μmol／L凋亡率（55．7％）比较,差异均有统计学意义,P〈0．01;各浓度作用48h后,HUT-78细胞抑制率分别为（22．85±10．98）％、（59．T7±5．44）％和（66．52±7．80）％,与0μmol／L细胞抑制率（O）比较,差异均有统计学意义,P〈0．01;与作用24h后同浓度细胞抑制率比较,差异均有统计学意义,P〈0．01。结论：达到5μmol／L的白藜芦醇对人皮肤T细胞淋巴瘤Hut-78细胞产生明显的抑制增殖作用,白藜芦醇主要通过诱导HuT-78细胞凋亡,其中主要是早期凋亡抑制其增殖。     

细胞外信号调节激酶1/2抑制剂对Burkitt淋巴瘤细胞增殖、凋亡和Bcl-2、Bcl-x1、caspase-3表达的影响

目的:分析细胞外信号调节激酶1/2抑制剂对Burkitt淋巴瘤细胞存活率、细胞凋亡和Bcl-2、Bcl-x1、caspase-3表达的影响。方法:通过不同浓度的细胞外信号调节激酶1/2抑制剂AZD8330对Raji细胞进行处理,通过CCK-8对其细胞存活率进行测定,采用流式细胞术对其细胞凋亡的情况进行检测。通过Western blot法对Bcl-2、Bcl-x1、caspase-3蛋白表达进行测定,且通过RT-PCR法对Bcl-2、Bcl-x1、caspase-3 mRNA的表达进行测定。结果:经0.50、1.00、5.00、50.00、100.00 μmol/L的AZD8330处理1、2、3 d后,随着AZD8330作用时间的增加与浓度的提高,Raji细胞存活率逐渐下降,并且各时间点的细胞存活率均低于对照组（P均＜0.05）。分别经0.50、1.00、5.00、50.00、100.00 μmol/L的AZD8330处理1、2、3 d后,Raji细胞出现凋亡,并且随着AZD8330作用时间的增加与浓度的提高,其凋亡率明显升高,且各时间点的细胞凋亡率均高于对照组（P均＜0.05）。随着处理时间的增加与浓度的提高,Bcl-2、Bcl-x1蛋白表达显著减少,caspase-3蛋白表达明显提高（P均＜0.05）;并且,Bcl-2、Bcl-x1 mRNA表达明显减少,caspase-3 mRNA的表达明显提高（P均＜0.05）。结论:AZD8330可能利用阻滞细胞外信号调节激酶1/2通路相关基因及蛋白的表达对Burkitt淋巴瘤Raji细胞凋亡进行诱导,并对其细胞增殖进行阻滞。     

鱼藤素对淋巴瘤Daudi细胞株细胞增殖细胞凋亡的影响及其机制

目的观察鱼藤素对人Burkitt淋巴瘤Daudi细胞株细胞增殖、细胞凋亡和细胞周期的影响,并探讨其分子机制。方法四甲基偶氮唑蓝(MTY)法检测细胞增殖活性,Hoechst 33258染色和Annexin-V／PI双标法检测细胞凋亡,流式细胞仪检测细胞周期分布,Western blot检测细胞内cyclin D1和pRb的蛋白表达。结果鱼藤素对Daudi细胞具有明显的增殖抑制作用,而对正常人外周血单个核细胞(PBMC)抑制作用不明显。鱼藤素可以诱导Daudi细胞凋亡,Hoechst 33258染色可见典型凋亡小体。Annexin V／PI双标法显示,鱼藤素诱导细胞发生早期凋亡,并呈剂量依赖性,20、40、80 nmol／L鱼藤素作用24 h时,凋亡率分别为15．46％±0．62％、18．48％±2．98％和31．42％±1．43％。鱼藤素作用Daudi细胞后,主要使细胞周期聚积于G0／G1期,G0／G1期细胞比例随鱼藤素剂量增大而逐渐增高,40 nmol／L鱼藤素作用24 h达56．56％;相反,S期细胞比例随鱼藤素剂量增大而逐渐降低,对G2／M期细胞作用不明显。鱼藤素使cyclin D1及pRb蛋白表达降低,呈剂量依赖关系。结论鱼藤素抑制Daudi细胞增殖,使细胞阻滞于G0／G1期,并诱导细胞凋亡。其抗肿瘤机制可能与下调cyclin D1和pRb蛋白表达有关。     

沉默GCB型弥漫大B细胞淋巴瘤细胞中AFAP1-AS1的表达对细胞增殖和凋亡的影响

目的:探讨沉默GCB弥漫型大B细胞淋巴瘤（diffuse large B cell lymphoma,DLBCL）中AFAP1-AS1的表达对细胞增殖和凋亡的影响。方法:培养GCB-DLBCL细胞至对数生长期后转染OCI-Ly1细胞系,建立的GCB-DLBCL细胞系对AFAP1-AS1表达进行沉默;实验设立3组,实验组为腺病毒感染细胞,sh-NC无关序列腺病毒感染细胞组为无关序列对照组,未感染腺病毒细胞组为空白组,应用PCR法检测AFAP1-AS1表达水平、CCK-8法测定细胞增殖情况、流式细胞术检测细胞凋亡情况,对比检测结果。结果:AFAP1-AS1表达水平检测结果显示:三种shRNA序列干扰效率均较无关序列对照组（sh-NC）强,差异有统计学意义（P＜0.05）;采用CCK-8法检测各组细胞凋亡情况,结果显示:经腺病毒sh3-AFAP1-AS1感染后,OCI-Ly1细胞系中实验组细胞吸光度较无关序列对照组和空白组显著降低,下调AFAP1-AS1可抑制GCB-DLBCL细胞的增殖（P＜0.05）;采用流式细胞仪检测各组细胞凋亡情况,结果显示:经sh3-AFAP1-AS1和sh-NC转染后,OCI-Ly1细胞实验组凋亡率明显高于无关序列对照组和空白组,下调AFAP1-AS1可诱导GCB-DLBCL细胞凋亡（P＜0.05）。结论:沉默GCB-DLBCL细胞中的AFAP1-AS1表达能有效抑制细胞增殖,诱导细胞凋亡,或可作为GCB-DLBCL治疗的靶目标。     

毛萼乙素抑制非霍奇金淋巴瘤细胞增殖作用及其机制探讨

目的 毛萼乙素(EriocalyxinB,EriB)是一种从唇形科植物疏花毛萼香茶菜中提取的二萜类化合物,具有很强的抗肿瘤细胞活性.本研究探讨EriB对非霍奇金淋巴瘤(non-Hodgkin's lymphoma,NHL)细胞增殖抑制及凋亡诱导、周期阻滞作用及机制.方法 采用MTT法检测5个浓度(0、0.2、0.4、0.6、0.8和1μmol/L) EriB处理72 h淋巴瘤细胞株的增殖抑制作用;流式细胞仪检测细胞凋亡率和细胞周期变化;蛋白质印迹法分析不同信号通路蛋白的表达.结果 0、0.2、0.4、0.6、0.8和1μmol/L浓度的EriB对淋巴瘤细胞均有增殖抑制作用,且抑制作用随着浓度增加而增强,半数生长抑制浓度在0.2～1.0μmol/L.流式细胞术检测显示,0.4μmol/L EriB作用Namalwa细胞24 h后G0/G1期细胞百分率为(44.71±4.10)％,对照组为(33.79±1.86)％,差异有统计学意义,Z=17.78,P=0.041;FCM结果显示,分析0.4μmol/L EriB作用Namalwa细胞6、12和24 h凋亡率分别为(4.21±1.06)％、(20.34±4.71)％和(29.91±5.39)％,显著高于对照组的(3.04±0.96)％,差异有统计学意义,H=8.56,P＜0.001.蛋白质印迹法分析显示,EriB处理后的Namalwa细胞蛋白p21、p27、p-Caspase-3、p-Caspase-8和p-Caspase-9表达上调,磷酸化NF-κB和其激活子IκB激酶表达下调.结论 EriB可能通过下调NF-κB信号通路诱导细胞凋亡,使细胞周期阻滞于G0/G1期,抑制淋巴瘤细胞增殖.     

Resveratrol induces colon tumor cell apoptosis independently of p53 and precede by epithelial differentiation, mitochondrial proliferation and membrane potential collapse.

Resveratrol, a polyphenol present in wine and grapes, can inhibit tumor cell growth in vitro and tumorigenesis in vivo. Some of its effects have been linked to activation of the p53 tumor suppressor; however, p53 is frequently mutated in tumors, particularly in the common and often therapy-resistant colon cancers. Using the human wild-type p53-expressing HCT116 colon carcinoma cell line and HCT116 cells with both p53 alleles inactivated by homologous recombination, we show in the current study that resveratrol at concentrations comparable to those found in some foods can induce apoptosis independently of p53. The cell death is primarily mitochondria-mediated and not receptor-mediated. No cells survived in cultures continuously exposed to 100 microM resveratrol for 120 hr. When compared with 5-FU, resveratrol stimulated p53 accumulation and activity only weakly and with delayed kinetics and neither the increased levels nor the activity affected apoptosis detectably. The apoptosis agonist Bax was overproduced in response to resveratrol regardless of p53 status, yet the kinetics of Bax expression were influenced by p53. Remarkably, apoptosis was preceded by mitochondrial proliferation and signs of epithelial differentiation. Thus, resveratrol triggers a p53-independent apoptotic pathway in HCT116 cells that may be linked to differentiation.     

阻断STAT3信号通路对恶性淋巴瘤细胞凋亡的影响

目的探讨阻断信号转导与转录激活因子3(STAT3)信号通路对恶性淋巴瘤细胞凋亡的影响。方法用0、200、400、800、1600 nmol/L的STAT3信号通路特异性阻断剂JSI-124作用于恶性淋巴瘤细胞株Raji,噻唑蓝(MTT)法检测细胞增殖水平,计算半数抑制浓度。用半数抑制浓度的JSI-124作用于Raji细胞,流式细胞术检测细胞凋亡和细胞周期,Western blot法检测细胞周期蛋白D1(cyclin D1)、STAT3、磷酸化的STAT3(p-STAT3)、活化的半胱氨酸天冬氨酸蛋白水解酶3(cleaved caspase 3)的蛋白相对表达水平。结果随着JSI-124作用浓度的升高,细胞存活率逐渐下降。计算半数抑制浓度为(615.62±52.98)nmol/L,故后续选用600 nm/L的JSI-124作用于恶性淋巴瘤细胞。600 nm/L作用组细胞凋亡率明显高于0 nm/L作用组(P﹤0.01)。600 nm/L作用组G0/G1期细胞所占比例明显低于0 nm/L作用组,G2/M期细胞所占比例明显高于0 nm/L作用组,差异均有统计学意义(P﹤0.01);两组S期细胞所占比例比较,差异无统计学意义(P﹥0.05)。600 nm/L作用组p-STAT3、cyclin D1蛋白相对表达水平明显低于0 nm/L作用组,cleaved caspase 3蛋白相对表达水平明显高于0 nm/L作用组,差异均有统计学意义(P﹤0.01)。结论阻断STAT3信号通路可促进恶性淋巴瘤细胞凋亡,抑制细胞增殖,将细胞周期阻滞在G2/M期。     

JNK/SAPK mediates doxorubicin-induced differentiation and apoptosis in MCF-7 breast cancer cells

Pharmacologic induction of cancer cell differentiation has potential in the treatment of breast cancer. Doxorubicin, a widely used anthracycline antibiotic, was previously reported to induce differentiation of MCF-7 breast cancer cells. We demonstrate in this study that inhibition of MCF-7 breast cancer cell growth by low dose doxorubicin (0.01 µg/ml) was accompanied by an increase in cytokeratin 8/18 and milk fat globule membrane protein expression, biomarkers for differentiation of breast cancer, as well as an increase in JNK/SAPK phosphorylation. High dose doxorubicin (10.0 µg/ml) induced apoptosis in these cells. Overexpression of dominant-inhibitory forms of JNK1 and c-Jun blocked both the differentiation and apoptotic effects of doxorubicin. These results suggest that JNK/SAPK pathway signaling plays a prominent role in doxorubicin-induced cell cycle withdrawal, differentiation and control of apoptosis in this cell system. These findings support the possibility that JNK/SAPK pathway activation may be a means of therapeutic intervention in breast cancer.     

利妥昔单抗与依鲁替尼对弥漫性大B细胞淋巴瘤细胞增殖和凋亡协同作用研究

目的 近年来发现依鲁替尼是B细胞恶性肿瘤的新型靶向药物,利妥昔单抗联合新药依鲁替尼对弥漫性大B细胞淋巴瘤(diffuse large B cell lymphoma,DLBCL)的研究逐步展开,本研究探讨利妥昔单抗与依鲁替尼对DLBCL细胞系Farage增殖及凋亡影响的协同作用.方法 不同浓度的单药利妥昔单抗和单药依鲁替尼处理Farage细胞24、48和72 h后,采用CCK8法检测细胞增殖抑制率.15 μmol/L依鲁替尼处理Farage细胞48 h后,采用RT-PCR法检测凋亡相关因子mRNA的表达变化.含人补体的培养条件下,1 μg/mL利妥昔单抗联合10 μmol/L依鲁替尼同时处理Farage细胞48 h后,采用CCK8法检测增殖抑制率,采用流式细胞术检测凋亡率.结果 利妥昔单抗在不含人补体的培养基中对Farage细胞增殖抑制作用不明显,在含人补体的培养基中有明显增殖抑制作用,并呈浓度和时间依赖性.依鲁替尼在含或不含人补体的培养条件下对Farage细胞均有明显增殖抑制作用,呈浓度和时间依赖性,2种条件下的增殖抑制率差异无统计学意义(F=0.978,P=0.329),15 μmol/L依鲁替尼作用Farage细胞48 h时,Fas(1.63±0.09)、Caspase-8(1.90±0.11)和Caspase-3(2.20±0.11)mRNA相对表达量均高于空白组(1.00±0.00).在含人补体的培养基中,1 μg/mL利妥昔单抗联合10 μmol/L依鲁替尼同时处理Farage细胞48 h后,联合组增殖抑制率为(57.06±1.48)%,高于依鲁替尼单药组(33.83±3.39)%和利妥昔单抗单药组(26.92±2.74)%,差异有统计学意义,F=87.403,P<0.001.联合组的凋亡和坏死率(44.30±2.20)%高于利妥昔单抗单药组(21.73±2.00)%和依鲁替尼单药组(17.44±1.60)%,且利妥昔单抗单药组和依鲁替尼单药组均高于空白组(2.32±0.21)%, 差异均有统计学意义,F=327.205,P<0.001.结论 利妥昔单抗可通过CDC效应引起DLBCL细胞凋亡坏死及增殖抑制,依鲁替尼可能通过上调Fas、Caspase-3和Caspase-8基因的表达,促使DLBCL细胞凋亡和增殖抑制,利妥昔单抗联合依鲁替尼对DLBCL细胞的增殖抑制和凋亡坏死作用明显强于单药利妥昔单抗或依鲁替尼.     

Hyperthermia induces differentiation without apoptosis in permissive temperatures in human erythroleukaemia cells

Purpose: The aim of the present study was to investigate whether induction of differentiation by hyperthermia is accompanied by apoptosis and necrosis to further evaluate the benefits of using hyperthermia as a differentiation inducing physical modality.

Materials and method: Differentiation was evaluated in K562 erythroleukaemia cells by measuring haemoglobin synthesis and flow cytometric measurement of glycophorin A expression. Apoptosis was measured by Annexin-V-FITC and Propidium Iodide (PI) double staining assay. Apoptosis and necrosis was also evaluated morphologically using staining with acridine orange/ethidium bromide (AO/EtBr) by fluorescence microscopy. Heat shock protein 70 (HSP70) level was measured by ELISA kit.

Results: Hyperthermia (43°C) induced differentiation as judged by increased haemoglobin synthesis and glycophorin A expression. No sign of apoptosis or necrosis could be detected at this temperature. Cell viability did not change due to heat treatment, and cellular proliferation was reduced in a dose (heating time) dependent manner. At 45°C, hyperthermia induced apoptosis and necrosis with minimal or no sign of differentiation. HSP70 level was significantly increased at 43°C along with differentiation of leukaemic cells, while at 45°C no significant effect on HSP70 production could be observed.

Conclusions: The encouraging results obtained here indicate that by heat treatment at 43°C, hyperthermia can be used alone or in combination with other modalities as a differentiation inducing agent without any detectable apoptotic activity. Positive correlation between HSP70 production and induction of differentiation and lack of apoptosis by hyperthermia confirm the possible role of HSP70 in the heat-induced differentiation and apoptosis in leukaemic cells.     

Prolonged daily administration of oral etoposide in lymphoma following prior therapy with Adriamicin,an ifosfamide-containing salvage combination,and intravenous etoposide

Prolonged daily administration of oral etoposide has been reported to be active in refractory lymphoma. The purpose of this phase II trial was to confirm the activity of this schedule of etoposide in a selected group of heavily pretreated patients with non-Hodgkin's lymphoma (NHL) or Hodgkin's disease (HD). A total of 26 patients (20 with NHL and 6 with HD) were entered in the trial; all had previously been treated with an Adriamycin-based chemotherapy, an ifosfamide-containing salvage combination, and i. v. etoposide. Etoposide was given in a fixed oral daily dose of 100 mg over 3 weeks; the weekly dose (500–700 mg) was selected such that the average daily dose was approximately 50 mg/m². Cycles were repeated on day 29. An objective response was seen in 16 patients (62%; 95% confidence interval, 42%–80%), with a complete response (CR) being observed in 3 cases (12%) and a partial response (PR), in 13 (50%). The median duration of PRs was 3 months. CRs lasted for 15 months in one patient and continue at 12+ and 20+ months in the remaining two patients. The overall actuarial survivial for the entire group was 40% at 2 years; the median survival time was 12 months. The main toxicity was myelosuppression; WHO grade 3 or 4 leukopenia and thrombocytopenia developed in 31% and 12% of the patients, respectively. There was no drug-related death. We conclude that oral etoposide is an effective and tolerable palliative treatment for heavily pretreated lymphoma patients.     

Pathology and clinical course of MALT lymphoma with plasmacytic differentiation.

BACKGROUND: The feature of plasmacytic differentiation (PCD) is present in up to 30% of patients diagnosed with mucosa-associated lymphoid tissue (MALT) lymphoma. To date, the influence of PCD on the clinical course of MALT lymphoma has not been assessed. PATIENTS AND METHODS: Therefore, we have retrospectively analysed the clinical characteristics and the course of the disease in 34 (25%) patients with PCD as compared with 101 (75%) MALT lymphoma patients without this histological feature. RESULTS: Patients with PCD had significantly more extragastric lymphomas [28 of 34 (82%) versus 54 of 101 (53%), P = 0.003] and a significantly lower rate of t(11;18) [2 of 26 (8%) versus 22 of 72 (31%), P = 0.02]. There was no significant difference of age at diagnosis (62 versus 64 years, P = 0.64), relapse rate (48% versus 37%, P = 0.27), estimated median time to progression (43 versus 65 months, P = 0.14), monoclonal gammopathy (50% versus 44%, P = 0.63), t(14;18) involving IGH/MALT 1 (11% versus 8%, P = 0.68), trisomy 3 (31% versus 27%, P = 0.69), trisomy 18 (8% versus 10%, P = 0.74) and the presence of autoimmune diseases between both groups (53% versus 37%, P = 0.09). CONCLUSION: In conclusion, we found that PCD is predominantly found in extragastric MALT lymphoma but has no significant impact on clinical course and prognosis.     

Targeting protein neddylation with an NEDD8-activating enzyme inhibitor MLN4924 induced apoptosis or senescence in human lymphoma cells

Recent studies indicate that post-translational protein neddylation is required for the maintenance of cell viability in several lymphoma cell lines, while inhibition of the neddylation pathway with an NEDD8-activating enzyme (NAE) inhibitor MLN4924 induces apoptosis in lymphoma cells. However, the mechanism by which neddylation inhibition induces apoptosis in lymphoma cells has not been fully elucidated. Moreover, it is unknown whether neddylation inhibition triggers non-apoptotic cell-killing responses, such as cell senescence, in lymphoma cells. Here, we report that MLN4924 specifically inhibited protein neddylation, inactivated cullin-RING E3 ligase (CRL), the best-known neddylation substrate, and induced the accumulation of tumor-suppressive CRL substrates in lymphoma cells. Moreover, MLN4924 potently suppressed the growth of lymphoma cells by inducing G2 cell-cycle arrest, followed by apoptosis or senescence in a cell line-dependent manner. MLN4924-induced apoptosis was mediated by intrinsic apoptotic signaling with substantial up-regulation of pro-apoptotic Bik and Noxa as well as down-regulation of anti-apoptotic XIAP, c-IAP1 and c-IAP2, while senescence induction upon neddylation inhibition seemed dependent on the expression of tumor suppressor p21/p27. Together, these findings expand our understanding on how lymphoma cells respond to neddylation inhibition and support the development of neddylation inhibitors (e.g. MLN4924) for the treatment of lymphoma.     

Notch1 signaling controls cell proliferation,apoptosis and differentiation in lung carcinoma

Objectives

The role of Notch signaling in human lung cancer still remains unclear, and there has been and stills a debate, on the extent to which Notch ligands and receptors are involved in lung cancer development. This study was carried out to investigate the role of Notch1 signaling in the proliferation and differentiation of human lung cancer cells.

Methods

We used small interfering RNA (siRNA) technology to down-regulate the expression of Notch1 in small cell lung carcinoma (SCLC) cells; H69AR and SBC-3, as well as in non-small cell lung carcinoma (NSCLC) cells; A549 adenocarcinoma (ADC) and H2170 squamous cell carcinoma (SCC). Also, we transfected venus Notch1 intracellular domain (v.NICD) plasmid into the human SCLC line H69 and H1688. In addition, H1688 cells with activated Notch1 were injected into immune-compromised Rag2(−/−) Jak3(−/−) mice for analysis of ex vivo tumor growth and differentiation phenotype.

Results

Notch1 controls cell proliferation and apoptosis in both SCLC and A549; but not in H2170 cell line. Overexpression of Notch1 in SCLC markedly decreased cell proliferation via apoptosis. The subcutaneous tumors arising from xenotransplaned SCLC cells transfected with Notch1 showed “epithelial-like glandular” arrangement, with positive Alcian blue staining and reduction in neuroendocrine markers.

Conclusion

Notch1 up regulation has an inhibitory effect on cell growth and NE differentiation in SCLC, with induction of an epithelial-like morphology of cells in tissue samples. In NSCLC, Notch1 expression has a tumor inhibitory effect on ADC cells, but not SCC cells.     

Regulation of apoptosis and proliferation in Ewing's sarcoma--opportunities for targeted therapy

The Ewing's sarcoma family of tumors are malignant tumors of bone and soft tissue which occur predominantely in children and adolescents. Whereas cure rates for patients with localized tumors are around 70%, survival rates for patients with metastases or relapse are poor in spite of intensive chemo- and radiation therapy, demonstrating a clear need for new, more effective therapies. Insights into the biology of the tumors of the Ewing's sarcoma family with identification of the EWS/ETS gene rearrangement as the key event in malignant transformation and its influence on the regulation of various pathways involved in proliferation, differentiation and apoptosis has led to the identification of potential targets for the development of new molecular therapeutics. This review will focus on the regulation of major pathways of proliferation and apoptosis in tumors of the Ewing's sarcoma family and point out how modulation of these pathways might be of potential use for future therapy.