rhTNFα对鼻咽癌 CNE3细胞p53及p21WAF1/CIP1蛋白表达的影响

瘤坏死因子α(tumor necrosis factor alpha, TNF-α)为活化的巨噬细胞分泌的一种蛋白质,具有多种生物活性,其细胞抑制效应（ cytostatic effect）可能由于上调 WAF1表达水平所致 [1, 2]。 p21WAF1/CIP1（简称为 WAF1）与细胞周期抑制蛋白 CIP1完全相同 [3],能将 DNA失常的细胞阻滞于 G1期进行修复或使之凋亡,其 DNA的启动子区含有一个 p53结合点,受野生型 p53基因（wtp53）调控。我们曾将 wtp53基因导入鼻咽癌细胞株 CNE3[4]并进行裸鼠致瘤抑制实验 [5],结果表明导入 wtp53基因有明显抑制移植瘤生长作用。现在此基础上进一步研究 CNE3裸鼠移植瘤经注射 TNF-α处理后抑瘤基因 p53及 WAF1表达的变化,为阐明这 3种抑瘤物质的相互作用机理提供实验依据。     

鼻咽癌中p53蛋白积聚对瘤细胞有丝分裂和凋亡的影响

目的：观察疗前鼻咽癌组织中Ｐ５３蛋白的积聚及其对瘤细胞有丝分裂和凋亡的影响。方法随机收集１９９７年疗前鼻咽癌活检标本４３例,采用免疫组化ＬＳＡＢ法ＤＯ－７一抗检测Ｐ５３蛋白的表达。在Ｈ＆Ｅ染色切片上位细胞死亡试剂盒检测瘤细胞凋亡,平均每个高倍视野下的凋亡瘤细胞数为凋亡指数（ＴＵＮＥＬ ｉｎｄｅｘ,Ｔ１）。比较高于位细胞死亡试剂盒检测瘤细胞凋亡,平均每个高倍视野下的细胞瘤细胞数为凋亡指数（ＴＵＮＥＬ     

鼻咽癌p53蛋白表达与p53基因结构改变及mdm2蛋白表达的关系和意义

探讨影响ＮＰＣｐ５３蛋白表达的因素,Ｐ５３和ｍｄｍ２蛋白在ＮＰＣ发生中的变化和意义。方法采用免疫组化法检测ｐ５３和ｍｄｍ２蛋白、Ｓｏｕｈｅｒｎ杂交法检测Ｐ５３基因结构。     

鼻咽癌p53 p21 WAF1和MDM2蛋白异常表达的临床意义

目的：探讨p53、p21^WAF1、MDM2蛋白在原发鼻咽癌（NPC）异常表达的临床意义。方法：采用LSAB法检测69例原发NPC组织中p53、p21^WAF1和MDM2蛋白的表达状况。结果：1）p53、p21^WAF1和MDM2蛋白在原发NPC组织的阳性表达率分别为79．7％、84．1％、和82．6％；高表达率分别为50．7％、46．4％和31．9％。2）p53蛋白的高表达率随TNM分期的升高而增多，P＝0．042。3）p53或MDM2蛋白高表达者的复发间期显著短于相应蛋白低表达／阴性者，分别P＝0．038和P＝0．002。4）p53和MDM2蛋白同时高表达者、MDM2蛋白高表达同时p21^WAF1蛋白低表达／阴性者的复发间期明显短于对照组，分别P＜0．001；p21^WAF1蛋白高表达同时p53蛋白低表达／阴性者、p53和MDM2蛋白同时低表达／阴性者的复发间期显著长于对照组，分别P＝0．002和P＝0．014。5）p53和MDM2蛋白高表达同时p21^WAF1蛋白低表达／阴性者的复发间期明显短于对照组，P＜0．001；p53和MDM2蛋白低表达阴性同时p21^WAF1蛋白高表达者的复发间期明显长于对照组，P＝0．002。结论：p53或MDM2蛋白高表达提示有促进NPC复发的作用，p21^WAF1蛋白高表达提示有抑制NPC复发的作用。单独检测p53或MDM2蛋白在原发NPC组织的表达情况可以和为预测NPC复发倾向和临床预后的参考指标；如同时检测p53、MDM2和p21^WAF1蛋白的两项或三项指标，预测意义更理想。     

细胞周期G1/S转换调控因子在喉癌癌变过程中的表达

目的 :探讨喉癌癌变过程中p2 1WAF1/CIP1、p53和cyclinDl表达的临床病理学意义。方法 :用免疫组化检测 2 0例正常粘膜、4 0例不典型增生病变和 60例喉癌组织中p2 1WAF1/CIP1、p53和cyclinDl 表达。结果 :①p2 1WAF1/CIP1、p53和cyclinDl 阳性表达定位于细胞核 ;②在喉癌癌变过程中 ,喉正常粘膜、不典型增生病变和喉癌中p2 1WAF1/CIP1阳性表达率分别为 95 0 % ( 19/2 0 ) ,75 0 % ( 30 /40 )和 63 3% ( 38/60 ) (P <0 0 5) ;p53阳性表达率分别为 :0 %、30 0 % ( 12 /40 )和 61 7% ( 37/60 ) (P <0 0 0 1) ;cyclinDl 阳性表达率分别为 5 0 % ( 1/2 0 )、30 0 % ( 12 /40 )、53 3% ( 32 /60 ) (P <0 0 0 1) ;③p2 1WAF1/CIP1在高、中和低分化的喉癌中阳性表达率分别为 76 2 % ( 16/2 1)、65 5% ( 19/2 9)和 30 0 % ( 3/10 ) (P <0 0 5) ;④cyclinDl 和p2 1WAF1/CIP1阳性表达显著相关 ,p2 1WAF1/CIP1和p53表达无相关性。结论 :①喉癌癌变过程中p53和cyclinDl 阳性表达率呈逐渐升高的趋势 ,而p2 1WAF1/CIP1阳性表达率呈逐渐降低的趋势 ;②p53和cy clinDl 异常表达是喉癌发生中早期分子事件 ;③p2 1WAF1/CIP1表达与喉癌细胞分化程度有关 ;④细胞周期调控因子p2 1WAF1/CIP1、p53和cyclinDl 相互调控机制     

p53蛋白在鼻咽癌中的表达及其临床意义

目的：从基因水平探讨抑癌基因ｐ５３蛋白与鼻咽癌的关系。方法：本文采用Ｗｗｓｔｅｒｍ ｂｌｏｔ结合非放射性免疫沉淀技术,对鼻咽癌细胞株、鼻咽癌活检组织和鼻咽粘膜慢性炎症组织进行了ｐ５３蛋白表达的研究。结果：７株鼻咽癌细胞株均发现ｐ５３蛋白表达异常条带。１０４例鼻咽癌活检组织中有１２例出现ｐ５３蛋白表达异常,检出率为１１．５４％。８例鼻咽慢性炎症活检组织中ｐ５３蛋白表达未见异常。１２例ｐ５３蛋白表达异     

复发鼻咽癌的治疗

目前放疗是鼻咽癌首选治疗手段且疗效令人满意,但仍有部分患者经积极治疗后出现复发,对这些患者的治疗有一定困难.近年来主要通过现代放疗、化疗和手术治疗等对复发鼻咽癌患者进行挽救治疗,临床效果得到认同.     

人鼻咽与鼻咽癌组织p53调节基因差异表达的研究

目的 用cDNA Array比较鼻咽癌组织及正常组织基因表达谱,研究鼻咽癌组织内p53调节基因表达差异。方法 Atlas人类肿瘤cDNA表达阵列7742－1滤膜杂交后,用AtlasImage 1.01a分析膜杂交结果,RT－PCR反应验膜杂交结果,免疫组化证实基因在蛋白质水平的表达改变。结果 在588个肿瘤相关基因中,共有134个基因表达上调,88个基因表达下调。膜上有p53调节基因32种,其中13种显示差异表达,有11个表达上调,2个表达下调。结论 在鼻咽癌组织内,p53的功能失控,MDM2、p21和Bax可能对鼻咽癌细胞的生长起重要的调控作用。     

复发鼻咽癌治疗现状

基于IMRT的综合治疗使初治非转移性鼻咽癌的 5年总生存率达到80%左右,局部区域控制率达90%以上,但初程治疗后仍有 10%~15%的患者出现局部和/或区域复发。鼻咽癌初程治疗后出现局部和/或区域复发的原因、再程治疗方案的选择以及再治后的不良反应和疗效,是影响再程治疗决策的主要因素。本文就上述问题结合近年进展进行综述。     

Cell cycle regulators and hematopoiesis

The cell cycle behavior of hematopoietic cells varies from extended quiescence to spectacular proliferation. Cell cycle regulators choreograph these transitions through variation in the makeup of cyclin-dependent kinase (cdk)-containing complexes and through alteration in protein expression levels and subcellular localization. The mechanisms through which cell cycle regulators couple proliferation, differentiation and survival is coming into sharper focus. Cdk-inhibitors, once thought of solely in terms of a checkpoint function on cycling, are now known to interact directly with proteins and pathways central to differentiation and apoptosis. By shuttling between binding partners committed to discrete functional pathways, cell cycle regulators may directly coordinate proliferation with differentiation, migration and apoptosis.     

模拟IMRT模式下相对剂量率变化对CNE-2细胞周期及Cyclin D1、Cyclin B1蛋白表达的影响

目的探讨模拟调强放射治疗（intensity-modulated radiation therapy IMRT）对人鼻咽低分化鳞癌细胞株（CNE-2）细胞周期及Cyclin D1、Cyclin B1蛋白水平的影响。方法选取CNE-2为实验对象,分为空白对照组、急速照射组（acute radiation AR）及模拟IMRT（simulational intensity-modulated radiation SIMR）组,后2组分别给予6MV-X线2、4、6、8 Gy 4个剂量点的照射。急速照射组完成时间1-3分钟;模拟IMRT组：各个剂量点分别等分分割5次,每次间隔8-8.5分钟,总时间35分钟照射完成。应用流式细胞术（FCM）分析细胞周期再分布的差异;应用Western blotting检测细胞周期相关因子Cyclin B1、Cyclin D1的蛋白水平。结果在相同剂量点,模拟IMRT组G2期细胞比例低于急速照射组,G2期细胞比例随照射剂量的增加而逐渐增加。急速照射与模拟IMRT组不同剂量点之间以及在相同剂量点比较,Cyclin D1的蛋白表达差异均无统计学意义（P值均〉0.05）;Cyclin B1的蛋白表达差异均有统计学意义（P值均〈0.05）,且随照射剂量的增加而下降,模拟IMRT组Cyclin B1的表达高于急速照射组。结论模拟IMRT照射时间延长,对G2期阻滞作用下降,细胞周期素Cyclin B1的表达相对升高。     

细胞周期调控因子在胃癌组织中的表达及意义

背景与目的细胞周期调控异常与细胞过度增殖及肿瘤发生密切相关,而细胞周期调控因子与胃癌的关系尚未明确。本研究目的是探讨细胞周期调控因子P16INK4、CyclinD1、P21WAF1、P53在胃癌组织中的表达及意义。方法运用免疫组织化学SP法检测53例胃癌及癌旁组织中细胞周期调控因子P16INK4、CyclinD1、P21WAF1、P53的表达。采用多变量Cox回归模型对影响预后的因素进行分析。结果P53蛋白在胃癌组织中的阳性率为60.4%,显著高于癌旁组织(0%)(P<0.01);P53蛋白表达在粘液癌(0%)与高分化腺癌(65.4%)和低分化腺癌(68.2%)间有显著性差异(P<0.01)。CyclinD1蛋白在胃癌组织中的过表达率为69.8%,显著高于癌旁组织(5.7%)(P<0.01)。P16INK4蛋白在胃癌组织中的阳性率为60.3%,显著低于癌旁组织(88.6%)(P<0.05)。P21WAF1蛋白在胃癌组织中的阳性率为26.4%,显著低于癌旁组织(56.6%)(P<0.01)。P16INK4表达与胃癌浸润深度及淋巴结转移相关(分别为P<0.05,P<0.01)。多因素Cox回归分析表明,淋巴结转移、P16INK4为独立预后因素。结论P16INK4蛋白、P21WAF1蛋白低表达和CyclinD1蛋白、P53过度表达与胃癌发生发展有关;P16INK4蛋白的低表达与胃癌浸润、转移及预后有一定关系。     

17β-Estradiol metabolites affect some regulators of the MCF-7 cell cycle

The activity of p34^cdc2 plays a key role in the regulation of the eukaryotic cell cycle. Another cell cycle associated molecule is PCNA. We investigated the effects of 2-hydroxy-17β-estradiol, a cell proliferator, and 2-methoxy-17β-estradiol, a potent inhibitor of cell growth, on the levels and activity of p34^cdc2 and on the levels of PCNA, as well as on protein phosphorylation in MCF-7 cells. 2-Hydroxyestradiol increased p34^cdc2 activity at G₁/S and elevated PCNA levels during S-phase. 2-Methoxyestradiol caused unscheduled activation of p34^cdc2 in S-phase and decreased levels of p34^cdc2 and PCNA during G₂/M. We conclude that 2-hydroxy- and 2-methoxyestradiol have definite, though different regulatory functions during the cell cycle.     

Differential expression of cell cycle regulators in CDK5-dependent medullary thyroid carcinoma tumorigenesis

Medullary thyroid carcinoma (MTC) is a neuroendocrine cancer of thyroid C-cells, for which few treatment options are available. We have recently reported a role for cyclin-dependent kinase 5 (CDK5) in MTC pathogenesis. We have generated a mouse model, in which MTC proliferation is induced upon conditional overexpression of the CDK5 activator, p25, in C-cells, and arrested by interrupting p25 overexpression. Here, we identify genes and proteins that are differentially expressed in proliferating versus arrested benign mouse MTC. We find that downstream target genes of the tumor suppressor, retinoblastoma protein, including genes encoding cell cycle regulators such as CDKs, cyclins and CDK inhibitors, are significantly upregulated in malignant mouse tumors in a CDK5-dependent manner. Reducing CDK5 activity in human MTC cells down-regulated these cell cycle regulators suggesting that CDK5 activity is critical for cell cycle progression and MTC proliferation. Finally, the same set of cell cycle proteins was consistently overexpressed in human sporadic MTC but not in hereditary MTC. Together these findings suggest that aberrant CDK5 activity precedes cell cycle initiation and thus may function as a tumor-promoting factor facilitating cell cycle protein expression in MTC. Targeting aberrant CDK5 or its downstream effectors may be a strategy to halt MTC tumorigenesis.     

Familial nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) has a striking geographical and ethnical distribution. It occurs with high frequency in southern China and Southeast Asia. Family clustering was also observed in NPC and a typical family with 15 NPC cases was introduced in this paper. Epidemiological and genetic studies have been carried out in the previous decades and vast information was accumulated for familiar NPC, in terms of risk factors, inheritance mode, and involvement of gene polymorphisms. The major findings in this field were summarized. Furthermore, future directions leading to understanding the genetic mechanism of the familial form of NPC was also discussed.     

EB病毒感染鼻咽癌细胞后的增殖周期变化

背景与目的:EB病毒(Epstein-Barrvirus,EBV)在不同组织类型鼻咽癌细胞内的增殖周期特征决定了基因治疗所采取的策略。本研究探讨EBV感染鼻咽癌细胞后的增殖周期特征。方法:利用EBV阳性的B95-8细胞标准株与鼻咽癌细胞CNE2接触培养,通过补体激活的细胞毒性试验去除共培养体系中的B95-8细胞,并采用逆转录聚合酶链式反应及Southern印迹杂交的方法分析鼻咽癌细胞中病毒的初始感染状态。结果:B95-8细胞与CNE2细胞接触共培养的方法使EBV成功感染CNE2细胞,EBV裂解期标志性基因BZLF1转录时间平均为12d,病毒感染标志性基因EBER转录时间平均为22d。结论:EBV侵入CNE2细胞后可能多数病毒开始处于裂解期增殖,之后EBV从裂解期进入了相对稳定的潜伏期,并随着细胞的传代培养病毒逐渐丢失。     

Epidemiology of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a rare malignancy in most parts of the world, with an incidence well under 1 per 100,000 person-years. Exceptions are the Chinese, especially the Cantonese living in the central region of Guangdong Province in Southern China. Other populations with elevated rates include the natives of Southeast Asia, the natives of the Artic region, and the Arabs of North Africa and parts of the Middle East. Intake of preserved foods at an early age has been linked to NPC risk in all population groups with increased NPC rates. Other recognized risk factors for NPC are cigarette smoking, and occupational exposure to formaldehyde and wood dust.     

Radiotherapy of nasopharyngeal carcinoma

The results of irradiation on fifty seven patients with nasopharyngeal carcinoma, treated from 1964 to 1985 at the Shinshu University Hospital, were studied. Forty-two percent of the patients had T3-4 primaries and 68% had N1-3 regional nodes; 86% had Stages III-IV of the disease. Of the 57 patients, 32 had squamous cell carcinomas, and 25 had lymphoepitheliomas. The overall 5-year survival rate was found to be 57%. Primary size (T) and histology influenced the survival of patients; the 5-year survival rate was 70% for T1-2 primary and 39% for T3-4 primary, and 39% for squamous cell carcinoma and 80% for lymphoepithelioma.