玉米苞叶对动脉粥样硬化家兔平滑肌细胞凋亡及p53和Fas蛋白表达的影响

目的：探讨玉米苞叶防治动脉粥样硬化（AS）的机制。方法：选用大耳白家兔，复制家兔AS模型，随机分为动脉粥样硬化模型组，玉米苞叶组和正常对照组，成模后给予玉米苞叶煎剂治疗，8w后处死家兔，采用流氏细胞术检测平滑肌细胞的凋亡率以及凋亡相关基因p53和Fas蛋白表达。结果：模型组血管平滑肌细胞的凋亡率明显高于对照组（P＜0．05），p53和Fas蛋白的表达增强（P＜0．05），主动脉壁肉眼观测出现典型斑块。玉米苞叶组平滑肌细胞的凋亡率明显低于模型组（P＜0．05），p53和Fas蛋白表达下调（P＜0．05）；主动脉斑块面积较模型组明显减小，结论：玉米苞叶通过调节p53和Fas蛋白表达而调节AS家兔平滑肌细胞凋亡。     

冠状动脉不稳定斑块中平滑肌细胞和炎性细胞PCNA阳性及TUNEL阳性细胞分布特点

目的　探讨增殖细胞核抗原 (PCNA)的表达和细胞凋亡在人冠状动脉不稳定斑块中的作用。方法　取人冠状动脉不稳定斑块标本 2 3例 ,采用免疫组织化学技术SP法检测细胞PCNA表达原位末端标记法 (TUNEL)检测细胞凋亡。结果　纤维帽区与肩部炎性细胞PCNA表达显著高于其余二区 ;脂核区平滑肌细胞、炎细胞TUNEL阳性细胞数明显高于其余三个区。纤维帽和肩部中平滑肌细胞和炎细胞PCNA阳性表达大于TUNEL阳性细胞数 (P <0 0 5;P <0 0 1) ;脂核内TUNEL阳性细胞明显大于PCNA阳性表达细胞 (P <0 0 1)。结论　冠状动脉不稳定斑块内细胞凋亡主要发生在斑块脂核周围 ,炎细胞的增殖主要发生在斑块的肩部     

兔动脉粥样硬化易损斑块中高表达热激蛋白70细胞与细胞凋亡的关系

目的:探讨热激蛋白(HSP)的高表达和细胞凋亡在兔动脉粥样硬化斑块中的作用。方法:取兔动脉粥样硬化易损斑块28例,镜下将斑块分为4个区,分别为纤维帽区、脂核区、肩部区和中膜平滑肌区;采用免疫组化技术检测各区不同细胞HSP70的高表达情况、原位末端标记法(TUNEL)检测各区不同细胞凋亡情况。结果:纤维帽区与肩部区HSP70的表达阳性炎性细胞数均显著高于脂核区、中膜平滑区,纤维帽区平滑肌细胞HSP70的阳性表达显著高于其他3个区。脂核区TUNEL阳性细胞数明显高于其他3个区。纤维帽区与肩部中表达HSP70的阳性细胞数大于TUNEL阳性细胞数(P<0.05,P<0.01);脂核区内TUNEL阳性细胞数明显大于表达HSP70的阳性细胞数(P<0.01)。结论:易损斑块内HSP70的高表达主要在纤维帽区及肩部区,而细胞凋亡主要在斑块脂核周围。     

动脉粥样硬化时平滑肌细胞凋亡的研究进展

动脉粥样硬化斑块中平滑肌细胞的凋亡随斑块发展不同程度而定。斑块沉亡及残作清除不足，可破坏纤维帽组织结构的平衡，影响斑块的稳定，使之易于破裂从而诱发临床事件（如心肌硬塞和碑苑）；凋亡可影响血管管腔的重的过程，例如对动脉狭窄部位行球囊扩张水后，设法加快内皮修复，促进凋亡，则对再狭窄的防治有积极意义二动脉凋亡可通过P53依赖性及非依赖性通路发生，还受自力无反调节和生长因子的问给调节．     

牛磺酸对兔动脉粥样硬化血管平滑肌细胞凋亡的影响

目的:探讨牛磺酸对兔动脉粥样硬化血管平滑肌细胞凋亡及凋亡相关基因bcl-2、bax和caspase-3蛋白表达的影响.方法:将24只日本大耳白兔随机分为正常对照组、高脂模型组和牛磺酸组,14周后观察各组主动脉组织病理形态学改变,透射电镜观察斑块内平滑肌细胞超微结构变化,流式细胞术检测动脉粥样斑块内平滑肌细胞凋亡率,免疫组化染色法检测凋亡相关基因bcl-2和bax蛋白表达,Western blot蛋白印记法检测caspase-3蛋白表达.结果:高脂模型组与正常对照组比较,动脉内膜出现典型的斑块,管腔极度狭窄,典型的凋亡平滑肌细胞明显增多,平滑肌细胞凋亡率、bax及caspase-3蛋白表达升高(P<0.01),bcl-2蛋白表达降低(P<0.05).牛磺酸组与高脂模型组比较,主动脉斑块缩小,动脉管腔狭窄减轻,凋亡平滑肌细胞不典型且较少,平滑肌细胞凋亡率、bax蛋白表达及caspase-3蛋白表达降低(P<0.01),bcl-2蛋白表达升高(P<0.05).结论:牛磺酸可能通过对bcl-2、bax及caspase-3蛋白表达的调控而降低动脉斑块内过度凋亡的平滑肌细胞,从而抑制粥样斑块的形成.     

葛根总黄酮对载脂蛋白E基因缺陷小鼠动脉粥样硬化病变内细胞凋亡及凋亡相关基因的影响

目的 探讨葛根总黄酮对载脂蛋白E基因缺陷（apoE-／-）小鼠主动脉窦动脉粥样硬化斑块抑制作用的分子机制。方法 采用电镜观察、缺口末端标记（TUNEL）法检测apoE-／-小鼠动脉粥样硬化斑块内的细胞凋亡。免疫组化方法检测平滑肌细胞、巨噬细胞及Caspase一3蛋白的表达。结果 电镜观察到凋亡细胞核形不规则,胞核内染色质浓集、边聚,附着在核膜周边,线粒体肿胀,内质网扩张,超微结构形态符合巨噬细胞早期凋亡,并可见典型凋亡小体形成。TUNEL结果表明,凋亡细胞主要分布在粥样斑块脂质核心处,模型组动脉粥样硬化斑块内凋亡细胞数较多,而葛根总黄酮干预组凋亡细胞数明显减少,葛根高、低剂量组细胞凋亡率明显低于模型组[分别为（0．38±0．17）ok,（1．95±1．02）％,（10．50±5．89）％,P〈0．01],葛根高剂量组细胞凋亡率明显低于葛根低剂量组。抗CD68抗体免疫组化染色证实在动脉粥样硬化斑块脂质坏死核心内细胞CD68强阳性表达。葛根高、低剂量治疗组Caspase-3蛋白免疫表达低于模型组,葛根高剂量治疗组低于葛根低剂量治疗组。结论 葛根总黄酮可能通过下调apoE-／-小鼠主动脉窦动脉粥样硬化病变内Caspases-3蛋白的表达,显著降低了动脉粥样硬化病变内巨噬细胞凋亡,从而抑制了动脉粥样硬化斑块的进展。     

凋亡基因与血管成形术后再狭窄的关系

本实验应用球囊拉伤动脉内膜加高脂饲养的方法建立兔髂动脉粥样硬化模型.对24只模型兔进行球囊扩张血管成形术.采用核酸分子杂交技术对髂动脉壁平滑肌细胞(SMC)的bcl-2和p53基因的表达情况进行实验观察.结果表明bcl-2在术后1周表达增强,p53在术后1周表达受抑制.提示血管成形术后早期由于抑制凋亡基因bcl-2表达增强,促进凋亡基因p53表达抑制共同导致细胞凋亡不足而促进了再狭窄的形成.     

放射治疗支架内再狭窄诱导平滑肌细胞凋亡的分子机制

目的 研究支架内再狭窄部位平滑肌细胞（rVSMC）凋亡水平改变的机制,并探讨放疗诱导细胞凋亡的调控途径.方法 50例支架术后再狭窄患者,取其斑块标本,检测p53、p21和Cyclin D1的表达水平,并与正常冠脉血管平滑肌细胞（nVSMC）进行比较.结果 rVSMC中,p53和p21的表达略低于正常细胞,分别为80%和75%左右（P＜0.05）;Cyclin D1则达到了正常细胞的2倍以上（P＜0.01）.照射后,rVSMC和nVSMC的细胞凋亡均有上升（P＜0.01）,且rVSMC的上升幅度大于nVSMC（P＜0.05）;而两组细胞中p53、p21和Cyclin D1的表达水平基本相同.结论 rVSMC中p53、p21和Cyclin D1的表达水平发生改变,导致细胞凋亡减少,是发生支架内再狭窄的重要原因.放疗可改变rVSMC中各凋亡相关分子的表达,诱导细胞凋亡.     

老年白内障晶状体上皮细胞凋亡及凋亡基因的表达

目的探讨老年白内障与晶状体上皮细胞凋亡的关系。方法TUNEL法检测凋亡细胞百分率；免疫组化法检测P53、bax在老年白内障晶状体上皮细胞中的蛋白表达；RT-PCR检测p53、bcl-2在老年白内障晶状体上皮细胞中的mRNA的表达水平。结果凋亡细胞百分率为5%～47.4%，P53蛋白在老年白内障晶状体上皮细胞中的表达率为15%～28%，bax蛋白的表达率为5%～16%，p53mRNA的表达率为0.48～0.78，baxmRNA的表达率为0.34～0.67。结论老年白内障的发生与晶状体上皮细胞凋亡存在一定的相关性。     

细胞凋亡蛋白bax和下肢动脉粥样硬化的关系

目的探讨细胞凋亡蛋白bax和下肢动脉粥样硬化的关系。方法收集正常对照组股动脉标本12例(正常对照组)。糖尿病及非糖尿病尸检病例的股动脉标本各8例分别为糖尿病组及非糖尿病组。将所有动脉标本每隔4 mm连续取材,常规病理学检查,并行免疫组织化学染色。结果正常股动脉内膜未发现bax的表达。动脉粥样硬化病变的脂纹中可见巨噬细胞bax的表达。但平滑肌细胞上未发现bax表达。在斑块中,bax在平滑肌细胞和巨噬细胞均有表达。和非糖尿病组比较,糖尿病组斑块中bax阳性的平滑肌细胞多,bax阳性的巨噬细胞少。结论细胞凋亡蛋白bax参与下肢动脉粥样硬化的形成。糖尿病可能通过影响斑块中bax的表达,使斑块不稳定。     

动脉粥样硬化斑块中细胞凋亡及其相关基因的表达

目的 :研究动脉粥样硬化 (AS)病灶中细胞凋亡的发生情况及其相关基因的表达情况 ,探讨细胞凋亡与bcl 2、p5 3、C myc基因表达的内在联系。方法 :选择因AS住院手术患者 2 0例作为研究对象〔其中男 17例 ,女 3例 ,平均年龄 (6 6 .8± 9.86 )岁 ,主要取患者的股动脉〕 ,及因意外伤害手术患者的 10例〔其中男 8例 ,女 2例 ,平均年龄 (5 1.6± 11.97)岁〕作为正常对照。采用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记 (TUNEL)技术检测两组动脉标本的细胞凋亡情况 ,采用免疫组化的方法检测bcl 2、p5 3及C myc基因的表达情况 ,应用透射电镜进行两组动脉标本的细胞形态学观察。结果 :AS病灶中 ,细胞凋亡的发生率明显高于正常对照血管 (P <0 .0 1) ,bcl 2蛋白的表达明显降低 ,p5 3蛋白及C myc蛋白的表达明显升高 (P <0 .0 1) ;透射电镜证实AS病灶中有大量的平滑肌细胞发生凋亡。结论 :细胞凋亡是AS病灶中细胞死亡的一种主要形式 ,bcl 2、p5 3及C myc基因的表达可能对细胞凋亡的发生起重要的调控作用。     

低Se低VE诱导肝细胞凋亡及相关基因所起的作用

目的 研究低硒（Ｓｅ）低维生素Ｅ（ＶＥ）能否诱导大鼠肝细胞凋亡及相关基因ｐ５３、ｂｃｌ－２和ｃ－ｍｙｃ所起的作用。方法 以天然的和人工半合成的低Ｓｅ低ＶＥ饲料喂养大鼠１７周,采用末端脱氧核苷酸转移酶介导的缺口末端标记（ＴＵＮＥＬ）检测肝细胞凋亡,采用免疫组化法检测肝细胞ｐ５３、ｂｃｌ－２和ｃ－ｍｙｃ蛋白。结果 与补Ｓｅ和ＶＥ组大鼠相比,低Ｓｅ低ＶＥ组大鼠肝细胞凋亡显著增加;ｐ５３和ｃ－ｍｙｃ蛋白增     

野生型P53基因导入诱导血管平滑肌细胞凋亡

为观察野生型P53基因诱导血管平滑肌细胞凋亡的现象，探讨对生型P53基因导入抑制平滑肌细胞增殖的作用机理，构建了野生型P53基因的重组腺病毒载体，体外转染兔主动脉血管平滑肌细胞。应用流式细胞议分析细胞周期，氚标胸腺嘧啶脱氧核苷掺入试验检测DNA合成，琼脂糖凝胶电泳观察DNA区带图谱，末端脱氧核苷酸转移酶介导的dUTP切口末端标记技术原位检测细胞凋亡。结果发现，野生型P53基因重组腺病毒载体转梁平滑肌细胞后，细胞内DNA合成减少。流式细胞仪分析显示77％的平滑肌细胞生长停滞在G0／Gl期，约45％的细胞发生细胞凋亡。dUTP切口末端标记阳性细胞百分率为40％～50％。DNA在琼脂糖凝胶电泳中呈现阶梯状区带图谱。以上结果提示，野生型P53基因通过诱导细胞凋亡对血管平滑肌细胞增殖起抑制作用。     

Accelerated smooth muscle cell apoptosis in occluded aorto-coronary saphenous vein grafts

It has been suggested that apoptosis contributes to the pathogenesis of atherosclerosis and to the instable plaque syndrome. The role of apoptosis in aorto-coronary venous graft occlusion is unknown. Therefore, we compared the occurrence of smooth muscle cell (SMC) apoptosis and apoptosis-related molecular markers in occluded vein grafts (CABG) with native coronary artery disease. Neointimal SMC of occluded CABG (n=30) and desobliterates from occluded native coronary arteries (n=65) were immunohistochemically stained in situ for the detection of p53, bax, bcl-2 and TUNEL (TdT-mediated dUTP-biotin nick endlabeling). The occurrence of apoptosis-promoting molecular markers and concomitant SMC apoptosis (% positive stained SMC ± SE) was significantly increased in occluded CABG compared to coronary artery desobliterates (p53: 6.8±2.3 versus 0 p<0.005; bax: 5.4±1.5 versus 3.6±0.9 p<0.05; TUNEL: 3.8±1.7 versus 1.1±0.4 p<0.05). SMC apoptosis is significantly increased in occluded venous grafts compared to primary coronary artery disease, and may play a role in the pathogenesis of vein graft disease. The documented increase in apoptosis-promoting molecular markers could be the basis for new therapeutic strategies for the prevention of venous graft occlusion.     

卡维地洛干预对转染p53基因家兔颈动脉粥样硬化斑块稳定性影响的研究

目的探讨卡维地洛（CAR）稳定动脉粥样斑块的作用。方法45只雄性日本大耳白兔随机分成5组,各9只。1组给予普通饲料作为正常对照组,其他4组给予球囊损伤颈总动脉加高脂喂养。8周后,其中3组给予野生053基因转染颈总动脉,2组分别加喂CAR（3mg·kg^-1·d^-1）和美托洛尔（MET,6mg·kg^-1·d^-1）,继续高脂饲料喂养4周。实验前和实验后8、12周,分别测定血脂、血清超敏C-反应蛋白、氧化型低密度脂蛋白、超氧化物歧化酶、丙二醛、谷胱甘肽过氧化物酶。实验结束后检测血管内膜平滑肌细胞凋亡率及053、bcl-2、bax、α-平滑肌肌动蛋白的局部表达情况,并分析血管病理形态。结果球囊损伤组均出现典型颈动脉粥样斑块。与未转染组相比,基因转染组053表达明显增加（P〈0．01）。与单纯转染组比较,MET及CAR组纤维帽厚度均明显增加,但以CAR更显著（P〈0．01）。CAR较MET血清超敏C-反应蛋白、氧化型低密度脂蛋白、丙二醛明显低,超氧化物歧化酶、谷胱甘肽过氧化物酶高（P〈0．05或0．01）,但对血脂均无明显影响。CAR组内膜平滑肌细胞凋亡率、bax及bax／bcl-2比值下降,α-平滑肌肌动蛋白和bcl-2阳性表达上调（P〈0．01）。结论CAR和MET均能促进斑块稳定,但以CAR为优,其机制可能在于CAR除B受体阻断作用外还具有抗炎、抗氧化、抑制血管内膜平滑肌细胞凋亡作用。     

Survey of molecular profiling during human colon cancer development and progression by immunohistochemical staining on tissue microarray

AIM： To explore the molecular events taking place during human colon cancer development and progression through high-throughput tissue microarray analysis. METHODS： We constructed two separate tissue microarrays containing 1.0 mm or 1.5 mm cylindrical samples acquired from 112 formalin-fixed and paraffinembedded blocks, including carcinomas （n = 85）, adenomatous polyps （n = 18）, as well as normal paracancerous colon tissues （n = 9）. Immunohistochemical staining was applied to the analysis of the consecutive tissue microarray sections with antibodies for 11 different proteins, including p53, p21, bcl-2, bax, cyclin D1, PTEN, p-Aktl, β-catenin, c-myc, nm23-h1 and Cox-2. RESULTS： The protein expressions of p53, bcl-2, bax, cyclin D1, β-catenin, c-myc, Cox-2 and nm23-h1 varied significantly among tissues from cancer, adenomatous polyps and normal colon mucosa （P = 0.003, P = 0.001, P = 0.000, P = 0.000, P = 0.034, P = 0.003, P = 0.002, and P = 0.007, respectively）. Chi-square analysis showed that the statistically significant variables were p53, p21, bax, β-catenin, c-myc, PTEN, p-Aktl, Cox-2 and nm23-h1 for histological grade （P = 0.005, P = 0.013, P = 0.044, P = 0.000, P = 0.000, P = 0.029, P = 0.000, P = 0.008, and P = 0.000, respectively）, β-catenin, comyc and p-Akt1 for lymph node metastasis （P = 0.011, P =0.005, and P = 0.032, respectively）, β-catenin, c-myc, Cox-2 and nm23-h1 for distance metastasis （P = 0.020, P = 0.000, P = 0.026, and P = 0.008, respectively）, and cyclin D1, β-catenin, c-myc, Cox-2 and nm23h1 for clinical stages （P = 0.038, P = 0.008, P = 0.000, P = 0.016, and P = 0.014, respectively）. CONCLUSION： Tissue microarray immunohistochemical staining enables high-throughput analysis of genetic alterations contributing to human colon cancer development and progression. Our results implicate the potential roles of p53, cyclin D1, bcl-2, bax, Cox-2, β-catenin and c-myc in development of human colon cancer and that of bcl-2, nm23-h1, PTEN and p-Akt1 in pro     

Dual effects of 8-Br-cAMP on differentiation and apoptosis of human esophageal cancer cell line Eca-109

AIM: To investigate the effects of 8-Br-cAMP on differentiation and apoptosis of human esophageal cancer cell line Eca-109, and the related gene expression. METHODS: The cultured Eca-109 cells were divided into four groups: E1 group (co-cultured with 8-Br-cAMP for 24 h); E2 group (co-cultured with 8-Br-cAMP for 48 h); C1 group (treated without 8-Br-cAMP for 24 h); and C2 group (treated without 8-Br-cAMP for 48 h). The same concentration of cell suspension of each group was dropped separately onto the slides and nitrocellulose membranes (NCM). The biotin-labeled cDNA probes for c-myc, wild-type (wt) p53, bcl-2 and iNOS were prepared for in situ hybridization. The expressions of epidermal growth factor receptor (EGFR), p38 kinase, FAS, FasL and caspase-3 were detected using immunocytochemistry, and the NOS activity and the ratio of differentiated cells/proliferating cells were examined by cytochemistry. Immunocytochemistry, cytochemistry, and in situ hybridization were separately carried out on both slides and NCM specimens for each group. In addition, TUNEL was used to detect the cell apoptosis rate in each group. RESULTS: The apoptotic rate of E2 group was significantly higher compared to E1 group, while there was no difference in the ratio of differentiated cells/ proliferating cells between E1 and E2 groups. The signals of wt p53 and iNOS were markedly stronger, while the signals of c-myc and EGFR were obviously weaker in E1 group than those in C1 group (P<0.05). Moreover, the signals of wt p53, iNOS, p38 kinase, caspase-3 and NOS activity were significantly stronger, whereas, the signals of bcl-2, c-myc and Fas/FasL were markedly weaker in E2 group than those in C2 group (P<0.05). CONCLUSION: The differentiation and apoptosis of human esophageal cancer cell Eca-109 can be induced after 24- and 48-h treatment with 8-Br-cAMP, respectively. Upregulation of wt p53, iNOS and downregulation of c-myc may be associated with differentiation and apoptosis of Eca-109 cells. Furthermore, upregulation of FasL, p38 kinase and caspase-3 as well as downregulation of bcl-2, and Fas may be involved in the apoptosis of Eca-109 cells.     

Apoptosis and its relationship with cell proliferation, p53, Waf1p21, bcl-2 and c-myc in esophageal carcinogenesis studied with a high-risk population in northern China

Ａｐｏｐｔｏｓｉｓａｎｄｉｔｓｒｅｌａｔｉｏｎｓｈｉｐｗｉｔｈｃｅｌｐｒｏｌｉｆｅｒａｔｉｏｎ,ｐ５３,Ｗａｆ１ｐ２１,ｂｃｌ２ａｎｄｃｍｙｃｉｎｅｓｏｐｈａｇｅａｌｃａｒｃｉｎｏｇｅｎｅｓｉｓｓｔｕｄｉｅｄｗｉｔｈａｈｉｇｈｒｉｓｋｐｏｐｕｌ...     

幽门螺杆菌体外诱导大鼠胃黏膜上皮细胞凋亡

目的:研究幽门螺杆菌(Hpylori)在大鼠胃黏膜上皮诱导细胞凋亡中的作用,并初步探讨其中凋亡相关基因表达的情况,为胃癌发病机制提供依据.方法:Hpylori超声提取液来自SydneySS-1Hpylori菌株.大鼠胃黏膜细胞OUMS-37为永生化细胞,当细胞生长至60%融合时,加入不同浓度的Hpylori超声提取液,同时设置空白,于培养的24-48h收集细胞进行形态观察.Westhernblotting检测P53蛋白表达,Northernblotting检测bax、bcl-2mRNA的表达.结果:细胞经Hpylori作用48h后在高倍镜下观察到细胞核碎裂成大小不等的块状,表现出细胞凋亡如细胞皱缩,胞浆嗜碱性,核染色质固缩致密,核染色质断裂,形成大小不等的胞内核小体,部分细胞核膜消失,核染色质聚集中细胞中央,呈现分裂期的形态学等形态学特征,对照组未出现以上特征性改变.培养细胞经过Hpylori作用后提取DNA,经15g/L琼脂糖凝胶电泳,在紫外线灯下观察呈现不连续的梯状结构电泳条带.培养细胞经过Hpylori作用后,Westhernblotting显示P53蛋白表达随Hpylori超声提取液浓度而升高,Northernblotting显示baxmRNA表达随Hpylori浓度而增加,bcl-2mRNA表达随Hpylori浓度而降低.结论:Hpylori超声提取液可在体外诱导鼠胃黏膜上皮细胞凋亡.其机制可能通过上调野生型P53蛋白和凋亡促进基因baxmRNA表达,并下调凋亡抑制基因bcl-2mRNA表达.提示Hpylori感染可通过干扰胃上皮细胞增殖与凋亡之间的平衡在胃癌病因学中发挥作用.     

Imbalance between cell proliferation and cellular DNA fragmentation in hepatocellular carcinoma.

AIM/BACKGROUND: Hepatocellular carcinoma (HCC) is known for its rapid growth. This study was undertaken to determine the expression of proliferative markers, apoptosis (DNA fragmentation) and oncogene products known to regulate apoptosis (p53, bcl-2) in HCC. METHODS: 150 Chinese patients with HCC were studied (M:F 128:22, age 14-88 years). Immunohistochemistry was employed to detect cell proliferative markers (PCNA, Ki67), and oncogene products known to regulate apoptosis (p53, bcl-2). DNA fragmentation was determined by terminal dUTP nick end labeling (TUNEL). RESULTS: 98% and 95% of HCC had PCNA (median 2+) and Ki67 (median 2+) detected respectively. TUNEL labeling was detected in only a small number of tumor cells (no labeling in 11%, median 1/1000 cell labeled, range: 0-70/1000 cells). There was no correlation between TUNEL labeling and the clinical parameters (sex, age, cirrhosis, and survival) and the expression of cell proliferative markers. p53 was detected in 53% of the patients (median 1+, range: 0-4+) and bcl-2 was detected in a small proportion of tumor cells in only 13% of the HCCs (range: 0-1 +). The expression of p53 and Bcl-2 did not correlate with TUNEL labeling or the natural survival. CONCLUSIONS: Cell proliferation in HCC is unmatched by apoptosis, accounting for the rapid growth of this tumor. This lack of apoptosis in HCC is unrelated to the expression of p53 or bcl-2 over-expression.