NS-398调节HepG2细胞组蛋白乙酰化和p21WAF1/CIP1表达

背景与目的:研究非甾体药物NS-398对人肝癌细胞株HepG2细胞组蛋白H3乙酰化水平的调节作用及对细胞周期素依赖性激酶抑制p21WAF1/CIP1表达的影响.材料与方法:用不同浓度(100、200、300、400μmol/L)的NS-398处理HepG2细胞,以四甲基偶氮唑蓝(MTT)法测定肿瘤细胞增殖抑制率,流式细胞仪(FCM)检测细胞周期的改变及凋亡百分率的变化,应用NS-398分别作用HepG2细胞4、8、12、24、48 h,非药物作用组作为对照,提取细胞的总RNA和总蛋白,采用RT-PCR技术检测p21WAF1/CIP1 mRNA表达情况,并用免疫印迹技术(Western blot)观察组蛋白H3的乙酰化水平变化及p21WAF1/CIP1蛋白的表达水平.结果:NS-398抑制HepG2细胞增殖,且呈剂量依赖性,并诱导其凋亡.且呈浓度依赖性改变细胞周期的分布,一方面增高G0/G1期细胞比例,另一方面降低S期和G2/M期细胞比例,与对照组相比差异具有统计学意义(P＜0.05).NS-398对组蛋白H3乙酰化作用随时间改变而变化,可引起组蛋白H3的乙酰化.NS-398对p21WAF1/CIP1 mRNA和p21WAF1/CIP1蛋白表达的影响呈时间依赖性.结论:NS-398明显上调HepG2细胞组蛋白H3的乙酰化水平,促进细胞周期依赖性激酶抑制剂p21WAF1/CIP1的表达.     

硒对乳腺癌细胞株p21^WAF1/CIP1启动子的调控作用

目的:研究硒对p21的转录调控及其调控位点.方法:通过向转染了重组质粒pGL3- p21p的乳腺癌细胞株MCF7先后加入不同的p21因子启动子的负调节因子和乳酸硒,对比分析荧光素酶表达活性,以确定硒对p21的转录调控及调控位点,并验证硒对癌细胞的生长的负调控作用.结果:perifosine、depsipeptide、apicidin、butyrate与硒共同诱导荧光素酶,酶活性表达无显著差异;而C-Myc与醋酸硒先后诱导酶活性表达差异显著.结论:硒对癌细胞具有诱导凋亡的作用,转录调节位点在p21启动子的sp1结合位点.     

胃肠道类癌中生长抑素和p21^WAF1/CIP1蛋白表达的意义

目的探讨生长抑素和p21WAF1/CIP1蛋白阳性表达与胃肠道类癌的组织分化、浸润和转移的关系.方法采用免疫组化S-P法对36例胃肠道类癌组织生长抑素和p21WAF1/CIP1蛋白的表达进行检测.结果 36例类癌组织中,生长抑素和p21WAF1/CIP1蛋白较多表达于高分化类癌组(P＜0.05),随着肿瘤的浸润和淋巴结转移,生长抑素阳性表达率显著降低(P＜0.01),p21WAF1/CIP1阳性表达差异有显著性(P＜0.05).结论生长抑素和p21WAF1/CIP1低表达在类癌的组织分化和发展中起着重要作用,可用于临床对患者进行预后判断.     

人脑胶质瘤组织中p21WAF1/CIP1表达及临床意义

[目的]探讨人脑胶质瘤组织中p21WAF1/CIP1基因蛋白表达水平与人脑胶质瘤恶性程度的关系。[方法]随机选取的Ⅰ￣Ⅳ人脑胶质瘤标本48例,正常外伤脑组织10例为对照。应用免疫组化技术(SP法)检测p21WAF1/CIP1基因蛋白在人脑胶质瘤中的表达水平。[结果]p21WAF1/CIP1基因蛋白在正常脑组织中均为阴性表达,而在胶质细胞瘤组织中表达增高,阳性率为70%￣78%,在Ⅰ～Ⅳ级胶质瘤组织中表达数值分别为2.11±0.10,1.44±0.56,1.0±0.12及0.89±0.32,表达水平随胶质瘤恶性程度的升高呈下降趋势,在高分化与低分化肿瘤之间存在显著性差异(P<0.05)。[结论]p21WAF1/CIP1可能参与胶质瘤的发生和发展,并可作为评估胶质瘤细胞瘤恶性程度以及预后的手段之一。     

p21WAF1/CIP1基因的转录调控机制及其与肿瘤的关系

 p21WAF1/ CIP1基因参与多条信号通路，在细胞周期、细胞分化及凋亡等重要的细胞活动中具有重要作用。文章对p21WAF1/CIP1基因转录调控机制及其与肿瘤的关系进行阐述，以进一步明确其在肿瘤诊断、治疗和预后评价中的应用价值。     

p21^WAF1／CIP1在原发性肺癌中的表达

目的：探讨p21^WAF1/CIP1在肺癌中的生物学功能,方法：用免疫组化法检测62例肺癌和14例正常肺组织石蜡切片p21^WAF1/CIP1的染色强度。结果：1．p21^WAF1/CIP1定位于细胞核或细胞浆。2．小细胞肺癌是与非小细胞肺中核p21^WAF1/CIP1表达存在显著性差异（P＜0．005）,浆p21^WAF1/CIP1则不存在显著性差异（P＜0．005）。核与浆p21^WAF1/CIP1表达的对比在高,低分化肺癌中具有显著性差异P＜0．05）。结论：肺癌细胞p21^WAF1/CIP1的生物学功能可能依其定位、量表达的高低及组织学类型的不同而存在差异。     

Induction of p53 and p21/WAF1/CIP1 expression by nitric oxide and their association with apoptosis in human cancer cells

In this study, human and rat cancer cells were used to investigate the expression of p53 and p21/WAF1/CIP1 and their association with apoptosis after exposure to nitric oxide (NO). It was found that NO induced nuclear accumulation of p53 protein in a dose- and time-dependent manner. The level of p53 protein was elevated by about fivefold compared with that of mock-treated cells 48 h after exposure to 300 ppm NO. The induction of p53 by NO was found by pulse-chase analysis to be mainly regulated by post-translational modification. The correlation between p53 status and apoptosis induced by NO in human cancer cells was also investigated in this study. We found that apoptosis was easily induced in cells containing wild-type p53 (COLO 205 and Hep G2) after exposure to NO. The p21/WAF1/CIP1 protein was induced by NO in cells containing wild-type p53 (Hep G2) but not in cells without p53 (Hep 3B) or with mutated p53 (HT-29). Our results indicate that wild-type p53 and p21/WAF1/CIP1 expression was elevated in human cancer cells by exposure to NO and suggest that this may eventually promote apoptosis. © 1996 Wiley-Liss, Inc.     

子宫内膜癌p21WAF1/CIP1蛋白的表达及其意义

背景与目的:探讨p21WAF1/CIP1蛋白在子宫内膜癌中的表达情况及其意义.材料与方法:应用免疫组织化学SP法检测30例正常子宫内膜,20例单纯性增生性宫内膜,22例不典型增生性宫内膜,57例子宫内膜癌(高分化32例,中分化12例,低分化13例)中p21WAF1/CIP1蛋白的表达. 结果:p21WAF1/CIP1蛋白表达于细胞核,子宫内膜癌中p21WAF1/CIP1蛋白的表达明显低于正常子宫内膜和单纯性增生性子宫内膜(P＜0.01),且p21WAF1/CIP1蛋白的表达与子宫内膜癌组织有无肌层浸润及临床分期明显相关(P均＜0.05).结论:p21WAF1/CIP1蛋白表达降低可能在子宫内膜癌的发生发展及判断预后方面具有重要作用.     

p21WAF1/CIP1和p53蛋白表达在胃癌发生发展过程中的研究

目的研究p21WAF1/CIP1和p53蛋白在胃癌发生发展过程中的作用及表达的临床病理意义.方法采用免疫组化SP法对正常胃粘膜、萎缩性胃炎伴肠上皮化生、萎缩性胃炎伴不典型增生组织各20例和78例胃癌组织标本进行p21WAF1/CIP1和p53蛋白检测.结果胃癌组织中p53蛋白阳性表达率高于正常胃粘膜、萎缩性胃炎伴肠上皮化生和不典型增生组(P＜0.05),而p21WAF1/CIP1蛋白阳性表达低于正常胃粘膜、萎缩性胃炎伴肠上皮化生组(P＜0.01)p21WAF1/CIP1、p53蛋白表达与胃癌的分化程度相关(P＜0.05);有淋巴结转移组p21WAF1/CIP1蛋白表达率低于无淋巴结转移组(P＜0.05),而有淋巴结转移组p53蛋白表达率高于无淋巴结转移组(P＜0.05);p53蛋白表达与胃癌浸润深度有关.结论p53蛋白高表达与p21WAF1/CIP1蛋白失表达可能参与胃癌的发生发展过程;检测p53和p21WAF1/CIP1蛋白作为反映胃癌病理学特点的参考指标可能有一定意义;p21WAF1/CIP1蛋白表达在胃癌可能存在非p53诱导表达途径.     

人乳腺癌中p21WAF1组蛋白H3、H4乙酰化水平的表达变化

[目的]探讨人乳腺癌中p21WAF1组蛋白H3、H4乙酰化水平的变化及其意义。[方法]应用HE染色鉴定乳腺癌的病理形态变化,RT—PCR检测p21WAF1mRNA的表达,染色质免疫沉淀法检测p21WAF1组蛋白H3、H4乙酰化的状态。[结果]HE染色可见,与癌旁组织及正常乳腺组织相比,乳腺癌组织结构及细胞形态有明显的异型性。RT—PCR检测结果显示,乳腺癌组织中p21WAF1mRNA的表达水平明显低于癌旁组织及正常乳腺组织（P〈0．05）;p21WAF1mRNA在组蛋白H3、H4乙酰化水平降低乳腺癌中的表达明显低于组蛋白H3、H4乙酰化水平非降低乳腺癌中的表达（P〈0．05）;p21WAF1mRNA表达降低与人乳腺癌的临床分期、分化程度和淋巴结转移有关。染色质免疫沉淀法显示,乳腺癌组织中p21WAF1组蛋白H3、H4的乙酰化水平明显低于癌旁组织及正常乳腺组织;p21WAF1乙酰化水平降低与人乳腺癌的分化程度和淋巴结转移有关。[结论]p21WAF1组蛋白H3、H4乙酰化的表达变化与乳腺癌的发生发展密切相关。     

p21WAF1/CIP1过表达对人肝癌细胞恶性表型和细胞凋亡的影响

目的 探讨Ｐ２１＾ＷＡＦ１／ＣＩＰ１过表达对人肝癌细胞恶性表型和细胞凋亡的影响。方法 用带有Ｐ２１的真核表达载体ＰＣＥＰ,经基因转染,使其在有Ｐ５３突变的人肝细胞癌细胞系（ＨＣＣ－９２０４）中表达;通过流式细胞仪、透射电镜和ＤＮＡ电泳确定凋亡的凋亡细胞。结果 转基因后Ｇ１期细胞增加,并且在Ｇ１期前出现一凋亡峰,凋亡细胞占被检细胞总数的２２．５％;电下可见部分细胞体积缩小,胞膜完整,有出芽现象,细胞     

Asiatic Acid Promotes p21WAF1/CIP1 Protein Stability through Attenuation of NDR1/2 Dependent Phosphorylation of p21WAF1/CIP1 in HepG2 Human Hepatoma Cells

Previous studies have suggested anti-tumor effects of asiatic acid in some human cancer cell lines. This agent isreported to increase the levels of p21WAF1/CIP1 in human breast cancer cell lines. However, the molecular mechanismshave not been established. Here we report that asiatic acid up-regulates p21WAF1/CIP1 protein expression but notthe level of p21WAF1/CIP1 mRNA in HepG2 human hepatoma cells. Furthermore, we found that the asiatic acidinduced increase of p21WAF1/CIP1 protein was associated with decreased phosphorylation (ser-146) of p21WAF1/CIP1.Knockdown of NDR1/2 kinase, which directly phosphorylates p21WAF1/CIP1 protein at ser-146 and enhances itsproteasomal degradation, increased the levels of p21WAF1/CIP1 protein and eliminated the regulation of p21WAF1/CIP1 stability by asiatic acid. At the same time, the expression of NDR1/2 kinase decreased during treatment withasiatic acid in HepG2 cells. Moreover, asiatic acid inhibited the proliferation of HepG2 cells, this being attenuatedby knockdown of p21WAF1/CIP1. In conclusion, we propose that asiatic acid inhibits the expression NDR1/2 kinaseand promotes the stability of p21WAF1/CIP1 protein through attenuating NDR1/2 dependent phosphorylation ofp21WAF1/CIP1 in HepG2 cells.     

p21~(WAF1/CIP1)在乳腺癌中的表达及意义

目的　探讨p2 1WAF1/CIP1蛋白在乳腺癌中表达的临床意义。方法　运用免疫组化SP法半定量检测p2 1蛋白在癌旁正常乳腺组织、乳腺癌组织中的表达。结果　p2 1蛋白表达位于细胞核 ,呈棕黄色。在 2 0例癌旁正常乳腺组织中 ,无p2 1蛋白表达。在 69例乳腺癌组织中有 3 0例p2 1蛋白阳性表达。在乳腺癌组织中 ,随组织学分级升高 ,p2 1阳性率下降 (P <0 0 5 ) ,随临床分期升高 ,p2 1阳性率下降 (P <0 0 5 )。有淋巴结转移组p2 1阳性率低于无淋巴结转移组 (P <0 0 5 )。p2 1蛋白阳性表达者术后 5年无瘤生存率高于p2 1蛋白阴性者术后 5年无瘤生存率 (P <0 0 5 )。结论　p2 1蛋白可用来评估乳腺癌细胞分化情况及转移潜能 ,可判断乳腺癌患者预后。     

Reduced p21(WAF1/CIP1) protein expression is predominantly related to altered p53 in hepatocellular carcinomas

To investigate the relationship between the expression of p21(WAF1/CIP1) protein and p53 status and the possible role of the two proteins in hepatocellular carcinomas (HCCs), we examined the expression of p21(WAF1/CIP1) and p53 immunohistochemically in 81 tumours from 65 patients with hepatocellular carcinoma. p21(WAF1/CIP1) protein was absent from 59 of 81 tumours (72.8%), and altered p53 expression was found in 43 (53.1%). p21(WAF1/CIP1) expression was significantly associated with p53 status (P = 0.0008); 38 of 59 tumours lacking p21(WAF1/CIP1) protein were accompanied by altered p53 expression. Further analyses showed that p21(WAF1/CIP1) expression was inversely correlated with p53 expression in hepatitis C virus (HCV)-related HCCs, but not in HBV-related hepatocellular carcinomas and hepatocellular carcinomas without viral infection. All 11 tumours with intrahepatic metastasis showed altered p21(WAF1/CIP1) or p53 expression. In contrast, no intrahepatic metastasis was found in any of the 17 tumours without abnormal expression of either of the two proteins. These results suggest that: (1) different modes of p21(WAF1/CIP1) regulation are involved in HCCs differing in their hepatitis viral infection status, and p21(WAF1/CIP1) expression appears to be predominantly related to altered p53 in HCV-related HCCs; (2) disruption of the p53-p21(WAF1/CIP1) cell-cycle-regulating pathway may contribute to malignant progression of HCC.     

细胞周期蛋白D1和p21WAF1/CIP1在喉癌癌变过程中表达及其意义

目的研究喉癌变过程中细胞周期蛋白(cyclin)D1和p21WAF1/CIP1表达及其临床病理学意义.方法用免疫组化检测20例正常黏膜、40例不典型增生病变和60例喉癌组织中cyclinD1和p21WAF1/CIP1的表达.结果①cyclin D1和p21WAF1/CIP1阳性表达定位于细胞核.②在喉癌癌变过程中,喉正常黏膜、不典型增生病变和喉癌中cyclin D1阳性表达率分别为5.0%(1/20),30,0%(12/40),53.3%(32/60)(P＜0.001);p21WAF1/CIP1阳性表达率分别为95.0%(19/20),75.0%(30/40)和63.3%(38/60)(P＜0.05).③p21WAF1/CIP1在高、中和低分化的喉癌中阳性表达率分别为76.2%(16/21),65.5%(19/29)和30.0%(3/10)(P＜0.05);p21WAF1/CIP1阳性表达与肿瘤细胞的分化有关.④cyclin D1和p21WAF1/CIP1阳性表达显著相关.结论①喉癌癌变过程中cyclin D1阳性表达率呈逐渐升高的趋势,而p21WAF1/CIP1阳性表达率呈呈逐渐降低的趋势.②cyclin D1异常表达是喉癌发生中早期分子事件.③p21WAF1/CIP1表达与喉癌细胞分化程度有关.④cyclin D1和p21WAF1/CIP1阳性表达显著相关.     

p21WAF1/CIP1和PCNA在骨肉瘤中的表达及对预后的评价

目的：探讨ｐ２１＾ＷＡＦ１／ＣＩＰ１基因ｍＲＮＡ及ｐ２１＾ＷＡＦ１蛋白,ＰＣＮＡ（增殖细胞核抗原）与骨肉瘤的发生,发展之间的关系及其对预后的评价。方法：采用原位杂交及免疫组化法（ＬＳＡＢ法）检测ｐ２１＾ＷＡＦ１／ＣＩＰ１基因ｍＲＮＡ及ｐ２１＾ＷＡＦ１蛋白、ＰＣＮＡ在骨肉中的表达。结果：原位杂交结果显示,ｐ２１＾ＷＡＦ１／ＣＩＰ１ ｍＲＮＡ在４５例骨肉瘤中有１９例阳性表达,阳性率为４２％;在１０例骨     

P21WAF1/CIP1蛋白表达与上皮性卵巢癌预后的关系

目的 探讨P21蛋白表达与上皮性卵巢癌预后的关系。方法 30例正常卵巢、30例良性卵巢肿瘤、108例上皮性卵巢癌标本用免疫组化的方法检测P21蛋白表达。结果 正常卵巢组、良性肿瘤组、卵巢癌组的P21蛋白阳性表达率分别为88．33％、80．00％、64．81％，恶性组阳性率低于其它两组(P=0．014)。P21(-)和P21( )患者的5年生存率分别为31．58％和47．14％，差异有显著性(P=0．0246)。结论 P21蛋白表达对判断上皮性卵巢癌预后有指导意义。     

胃癌中p21WAF1/CIP1、细胞周期素D1、p53表达的相关性

目的　探讨p2 1WAF1/CIP1、细胞周期素D1(cyclinD1)、p5 3在胃癌中表达之间的相关性。 方法　应用原位杂交技术检测p2 1WAF1/CIP1mRNA、细胞周期素D1mRNA及免疫组化技术检测p5 3蛋白在胃癌中的表达。结果　p2 1WAF1/CIP1mRNA在癌组织及癌旁正常粘膜中阳性表达率各为 93.15 % (6 8/73)及76 .71% (5 6 /73) ,二者相比具有显著差异 (P <0 .0 5 )。CyclinD1mRNA在癌组织及癌旁正常粘膜中阳性表达率各为 5 4 .79% (40 /73)及 30 .16 % (2 2 /73) ,二者具有显著差异 (P <0 .0 5 )。p5 3蛋白在胃癌中的阳性表达率为 32 .87% (2 4 /73) ,p5 3过表达者 ,其 p2 1WAF1/CIP1mRNA表达较p5 3阴性者为低 ,二者存在显著差异 (P <0 .0 5 )。p2 1WAF1/CIP1表达与细胞周期素D1表达呈负相关。结论　p2 1WAF1/CIP1、CyclinD1、p5 3的异常表达及它们之间可能存在的相互作用 ,对于胃癌的发生发展具有重要意义。     

Sensitivity to the non-COX inhibiting celecoxib derivative, OSU03012, is p21(WAF1/CIP1) dependent

OSU03012 is a non-COX inhibiting celecoxib derivative with growth inhibiting and apoptotic activity in many cancer cell lines. To investigate mechanisms related to cell cycle proteins in growth inhibition and apoptosis induced by OSU03012, the primary human oral epithelial cell line, TE1177, was transformed with HPV16 E6 (TE/E6), HPV16 E7 (TE/E7) or empty vector (TE/V). TE/E6 cell lines exhibiting low levels of p53 and undetectable levels of p21(WAF1/CIP1) were sensitized to the growth inhibiting and apoptotic effects of OSU03012. The TE/E7 cell lines expressing low levels of Rb and elevated levels of p53 and p21(WAF1/CIP1) were resistant. OSU03012 reduced the number of cells in the S phase of the TE/E7 and TE/V cell lines with intact p53-p21(WAF1/CIP1) checkpoint, but not in the checkpoint defective TE/E6 cell lines. Treatment with OSU03012 also markedly reduced the levels of cyclin A and Cdk2 in TE/E7 and TE/V, but not in TE/E6 cell lines, which had significantly enhanced basal levels of cyclin A and Cdk2. Consistent with the TE/E6 cell line, p21(WAF1/CIP1)-/- mouse embryo fibroblasts were more sensitive to OSU03012-induced apoptosis as evidenced by PARP and caspase 3 cleavages. These data suggest that p21(WAF1/CIP1) is an important factor in the sensitivity of cells to the growth inhibiting and apoptotic effects of OSU03012.