Inhibition of adenovirus-mediated p27kip1 gene on growth of esophageal carcinoma cell strain

AIM: To investigate the inhibition of p27kip1 gene on the growth of esophageal carcinoma cell strain (EC9706).METHODS: Recombinant adenovirus Ad-p27kip1 was constructed and transfected into esophageal carcinoma cell EC-9706, and its effect on p27kip1 expression, the growth of esophageal carcinoma cell, DNA replication, protein synthesis, cell multiplication and apoptosis were explored by means of cell growth count, 3H-TdR, 3H-Leucine incorporation,flow cytometry, DNA fragment analysis and TUNEL.RESULTS: Recombinant adenovirus Ad-p27kip1 was successfully constructed with a virus titer of 1.24x1012 pfu/ml.p27kip protein expression increased markedly after EC-9706 transfection, while incorporation quantity of 3H-TdR and 3HLeucine decreased significantly. The growth of esophageal carcinoma cell was inhibited obviously. Testing of flow cytometry displayed a typical apoptosis peak, and DNA gel electrophoresis showed a typical apoptosis ladder. TUNEL showed the apoptosis rate of Ad-p27kip1 group and control group to be 37.3 % and 1.26 % (P<0.001) respectively.CONCLUSION: Ad-p27kip1 can inhibit the growth and multiplication of esophageal carcinoma cells and induce apoptosis. Therefore, enhanced p27kip1 expression may be a new way to treat esophageal carcinoma.

Expression of p27Kip1, A Cell Cycle Repressor Protein with Dual Roles for Both Cancer Prevention and Promotion, Is Regulated Primarily at the Level of Unusual p27Kip1 mRNA—A Short Concept Proposal

The p27Kip1 is a cell cycle repressor protein that regulates primarily the cell cycle transition from G1 to S phase and hence the DNA replication is in the S phase and cell division in the M phase. Expression of p27Kip1 protein has dual roles for both cancer prevention and promotion. For example, numerous nutritional and chemopreventive anti-cancer agents specifically increase the expression of p27Kip1 protein without directly affecting the expression of any other cell cycle regulatory proteins. On the other hand, pro-cancer agents (like glucose, insulin and other growth factors frequently seen in obesity and/or diabetes) specifically decrease the expression of p27Kip1 protein without directly affecting the expression of any other cell cycle regulatory proteins. Unlike expression of any other cell cycle regulatory proteins, expression of p27Kip1 protein is very unusual. The mRNA of p27Kip1 has a very long and unusual 5’-untranslated region (from -575 to -1 in human). It appears that the 5’-untranslated region of p27Kip1 mRNA forms two alternative secondary structures. One increases the expression of p27Kip1 protein when anti-cancer agents are added and another decrease the expression of p27K1p1 when pro-cancer agents are added. For this short concept proposal, Dr. Albert Einstein’s “visualized thought experiments (German: Gedanken experiment)” were used as a fundamental tool for understanding how either anti- or pro-cancer agents bring the primary structure of the 5’-untranslated region of p27Kip1 mRNA into two alternative secondary structures, thereby either increasing or decreasing, respectively, the translation initiation of p27Kip1 protein.

Expression and significance of cyclin D1, p27kip1 protein in bronchioloalveolar carcinoma

Purpose: To investigate the relationship between expression of cell cycle-related protein cyclin D1, p27kip1 and the pathogenesis of bronchioloalveolar carcinoma (BAC) and the value of prediction of prognosis. Methods: Cyclin D1 and p27kip1 protein were detected by immunohistochemical En Vision method in 43 BACs. Results: The positivity of cyclin D1 in BAC was 65.1% (28/43), which was significantly higher than that in normal pulmonary tissue (0/13), P<0.01. No statis-tically significant association was found between cyclin D1 expression data and sex, age, tobacco-use history, histologic subtype (mucinous vs nonmucinous), stromal fibrosis, lymph node metastasis, clinical stage or postoperative survival period (P>0.05), while cyclin D1 expression was found to be negatively correlated with tumor size (P<0.05). The positivity of p27kip1 in BACs was 51.2% (22/43), significantly lower than that in normal pulmonary tissue (12/13), P<0.01. p27kip1 expression level was not associated with sex, age, tobacco-use history, tumor size or histologic subtype (P>0.05), but was negatively correlated with stromal fibrosis, lymph node metastasis and clinical stage (P<0.05); and positively associated with postoperative survival period (P<0.01). The survival rate of p27kip1 positive group was significantly higher than that of p27kip1 negative group (P<0.01). No statistically significant correlation was found between cyclin D1 and p27kip1 expres-sion. Conclusions: Increased cyclin D1 expression and decreased p27kip1 expression are related to the pathogenesis of BAC; decreased p27kip1 expression is associated with metastasis progression; immunodetection of p27kip1 is useful for assessment of prognosis.

Higher Concentrations of Glucose or Insulin Increase the Risk of Various Types of Cancer in Obesity or Type 2 Diabetes by Decreasing the Expression of p27Kip1, a Cell Cycle Repressor Protein

Research Aims: Obesity and type 2 diabetes are known to be associated with increased risk of various types of cancer. However, the molecular biological mechanism of how the risk of cancer is increased in obesity or type 2 diabetes is not known. The aim this research is to investigate if the decreased expression of p27Kip1, a cell cycle repressor protein, plays a central role in this mechanism. Research Methods, Previous Studies and Theoretical Backgrounds: It is well known that the expression of p27Kip1 is increased by numerous nutritional or chemopreventive anti-cancer agents. But it has never been known that the expression of p27Kip1 could be decreased, rather than increased, and the risk of cancer could be increased, rather than decreased. This problem was solved recently and this new analytical method was used in this study. Results: 1) The expression of p27Kip1 was indeed significantly decreased in human obese type 2 diabetic individuals relative to the lean normal controls. 2) The expression of p27Kip1 was also significantly decreased in genetically obese rodents relative to the lean normal controls. Additionally, in obese rodents, the concentrations of glucose or insulin were significantly increased relative to the lean normal controls. 3) Using human cells cultured in vitro it was found that the increased concentrations of glucose or insulin decrease the expression of p27Kip1. Conclusions: These results suggest that higher concentrations of glucose or insulin increase the risk of various types of cancer in obesity or type 2 diabetes by decreasing the expression of p27Kip1.

CacyBP/SIP nuclear translocation regulates p27Kip1 stability in gastric cancer cells

AIM: To investigate the mechanism of calcyclin binding protein/Siah-1 interacting protein(Cacy BP/SIP) nuclear translocation in promoting the proliferation of gastric cancer(GC) cells. METHODS: The effect of Cacy BP/SIP nuclear translocation on cell cycle was investigated by cell cycle analysis. Western blot analysis was used to assess the change in expression of cell cycle regulatory proteins and proteasome-mediated degradation of p27Kip1. Coimmunoprecipitation(co-IP) analysis was performed to examine the binding of Cacy BP/SIP with Skp1. A Cacy BP/SIP truncation mutant which lacked the Skp1 binding site was constructed and fused to a fluorescent protein. Subsequently, the effect on Skp1 binding with the fusion protein was examined by co-IP, while localization of fluorescent fusion protein observed by confocal laser microscopy, and change in p27Kip1protein expression assessed by Western blot analysis.RESULTS: Cacy BP/SIP nuclear translocation induced by gastrin promoted progression of GC cells from G1 phase. However, while Cacy BP/SIP nuclear translocation was inhibited using si RNA to suppress Cacy BP/SIP expression, cell cycle was clearly inhibited. Cacy BP/SIP nuclear translocation significantly decreased the level of cell cycle inhibitor p27Kip1, increased Cyclin E protein expression whereas the levels of Skp1, Skp2, and CDK2 were not affected. Upon inhibition of Cacy BP/SIP nuclear translocation, there were no changes in protein levels of p27Kip1 and Cyclin E, while p27Kip1 decrease could be prevented by the proteasome inhibitor MG132. Moreover, Cacy BP/SIP was found to bind to Skp1 by immunoprecipitation, an event that was abolished by mutant Cacy BP/SIP, which also failed to stimulate p27Kip1 degradation, even though the mutant could still translocate into the nucleus.CONCLUSION: Cacy BP/SIP nuclear translocation contributes to the proliferation of GC cells, and Cacy BP/SIP exerts this effect, at least in part, by stimulating ubiquitin-mediated degradation of p27Kip1.

Expression and Clinical Significance of p27kip1 Protein in Primary Liver Cancer

Summary: To investigate the expression and clinical significance of p27kip1 protein in primary liver cancer, the expression of p27kip1 protein and the relationship with clinicopathological factors were studied in primary liver cancer by using SABC immunohistochemical staining in specimens of 40 cases of primary liver cancer and 20 cases of liver cirrihosis. Our results showed that positive expression rate of p27kip1 protein in primary liver cancer was 37.5 % (15/40), which was lower than that in benign lesion of liver 80.0 % (16/20, P<0.01). The expression level of p27kip1 protein in primary liver cancer showed significant differences in tumor size, Edmonson histological grade, portal invasion, lymph node metastasis, TNM stage (P<0.05, for all), but not significantly correlated with patient's age and histological types. Log rank test showed that the p27kip1 expression was significantly related with prognosis of the patients (P<0.05), and the prognosis of the patients with p27kip1 positive expression was markedly better than that of those with p27kip1 negative expression. It is concluded that the expression of p27kip1 was significantly related clinicopathological factors of primary liver cancer. p27kip1 protein may be used as a novel tumor marker for primary liver cancer.

Effect of p27Kip1 Inhibition on Proliferation of Bovine Corneal Endothelial Cells by RNA Interference

Three plasmids （pGenesil-P1, pGenesil-P2, pGenesil-P3） with different p27Kip1-shRNA sequences were designed and synthesized. Their effects on the proliferation of bovine corneal endothelial cells （bCEC） were investigated. Plasmid expressing irrelevant shRNA with a random combination was used as negative control （pGenesil-HK）. The recombination of four plamids was confirmed by restrictive enzyme digestion and sequence analysis. The expression of mRNA and protein of p27Kip1 was detected by RT-PCR and Western blotting after stable transfection. The expressions of p27Kip1 mRNA and p27Kip1 protein of pGenesil-P1 group, pGenesil-P2 group and pGenesil-P3 group were all lower than those in the pGenesil-HK group and the blank group （non-transfected group）, pGenesil-P3 had the strongest inhibitory effect and was selected for the next steps. The proliferation rates of the pGenesil-P3 group, the pGenesil-HK group and the blank group were assessed by MTT. The influence of shRNA-p27Kip1 on bCEC cell cycle was detected by flow cytometry （FCM）. Compared with the control groups, the proliferation rate of the pGenesil-P3 group was increased significantly, and the ratio of S-phase also increased. It is concluded that shRNA-p27Kip1 could down-regulate the expression of p27Kip1 effectively and increase the proliferation of bCEC. RNA interference （RNAi） may be an effective means to promote the proliferation of CEC.

Lower Concentrations of Glucose or Insulin Decrease the Risk of Various Types of Cancer in the Long-Lived Ames Dwarf Mouse by Increasing the Expression of p27Kip1, a Cell-Cycle Repressor Protein

Introduction. The molecular biological mechanism of the increased incidence of the various types of cancer in obesity or type 2 diabetes in rodents or humans has largely been resolved in recent years. By contrast, the molecular biological mechanism of the decreased, not increased, incidence of the various types of cancer in the homozygous long-lived Ames dwarf mice still remains unresolved. Objective. The first objective of the present study was to investigate whether the decrease in the incidence of cancer in the homozygous long-lived Ames dwarf mice is due to the increase, not decrease, in the expression of p27Kip1, a cell cycle repressor protein. The second objective was to investigate whether the decrease in the incidence of cancer in the homozygous long-lived Ames dwarf mice is due to the decrease, not increase, in the levels of glucose or insulin. Methods. To achieve these objectives, we first performed western immunoblot analysis of the hepatic expression of p27Kip1 protein. We then performed, using a human breast cancer cell line in vitro, the luciferase reporter plasmid assay to determine whether the translation initiation activity of the p27Kip1 mRNA is increased when the concentrations of either glucose or insulin are decreased. Results and Conclusion. The results of the first objective indicated that the hepatic expression of p27Kip1 protein was up-regulated in the homozygous long-lived Ames dwarf mice as expected. We also found that the lower concentrations of glucose or insulin increased the translation initiation activity of the p27Kip1 mRNA.

长链非编码RNA BC002811对胃癌细胞活性、细胞间质转化及p27kip1活化的影响

目的:探究长链非编码RNA(LncRNA) BC002811对胃癌细胞活性、细胞间质转化及p27kip1活化的影响。方法 :收集本院原发性胃癌手术切除样本50例,采用TaqMan RNA试剂盒检测BC002811的相对表达量。将胃癌细胞株HGC-27细胞培养及转染后分为HGC-27组(无转染的HGC-27细胞)、BC002811-NC组(HGC-27细胞+BC002811 siRNA-NC)、BC002811组(HGC-27细胞+BC002811 siRNA);HGC-27组、空载体组(HGC-27细胞+p27kip1空质粒)、p27kip1组(HGC-27细胞+p27kip1质粒);HGC-27组、BC002811+空载体组(HGC-27细胞转染BC002811+p27kip1空质粒)、BC002811+p27kip1组(HGC-27细胞转染BC002811+p27kip1)。Transwell分别检测各组HGC-27细胞侵袭、转移能力,采用免疫印迹检测HGC-27细胞vimentin、E-cadherin蛋白表达,采用qRT-PCR检测HGC-27细胞BC002811、p27kip1表达。结果 :与胃癌组织比较,癌旁组织BC002811的表达显著降低。与HGC-27组比较,BC002811组HGC-27细胞侵袭、迁移能力及E-cadherin表达水平显著降低,vimentin表达水平升高,HGC-27组与BC002811-NC组差异无统计学意义。与HGC-27组比较,p27kip1组HGC-27细胞的侵袭、迁移能力及E-cadherin表达水平显著降低,vimentin表达水平升高,HGC-27组与空载体组差异无统计学意义。与HGC-27组比较,BC002811+空载体组HGC-27细胞侵袭、迁移能力及E-cadherin表达水平显著降低,vimentin表达水平升高;与BC002811+空载体组比较,BC002811+p27kip1组HGC-27细胞侵袭、迁移能力及E-cadherin表达水平显著降低,vimentin表达水平升高。Pearson相关分析结果显示,在HGC-27细胞侵袭、迁移中,BC002811与vimentin水平呈负相关性,与E-cadherin水平呈正相关;vimentin与E-cadherin水平呈负相关性。结论 :在胃癌细胞中BC002811-siRNA激活p27kip1水平、抑制胃癌细胞的迁移及侵袭,其作用机制可能与调控胃癌细胞间质转化蛋白表达相关。

skp2及p27Kip1蛋白与晚期胃癌患者临床预后的关系

目的探讨细胞S期激酶相关蛋白(skp)2及p27Kip1蛋白与晚期胃癌患者临床预后的关系。方法选取2013年5月至2015年1月开滦点医院林西医院收治130例晚期胃癌患者,免疫组化法检测skp2和p27Kip1蛋白表达水平,采用单因素和多因素Cox回归模型,探讨skp2和p27Kip1蛋白表达与晚期胃癌临床预后的关系。结果晚期胃癌组织skp2和p27Kip1阳性表达在不同卡氏功能状态(KPS)评分、肿瘤直径、手术、腹腔淋巴结转移、肝转移、临床分期及组织学分化患者中差异存在统计学意义(P<0.05),而性别、年龄、化疗、放疗及腹水等指标差异未见统计学意义(P>0.05)。年龄、KPS评分、肿瘤直径、手术、化疗、放疗、腹腔淋巴结转移、肝转移、腹水、临床分期、组织学分级、skp2蛋白表达和p27Kip1蛋白表达水平是晚期胃癌患者5年存活的影响因素。Cox回归分析结果显示,KPS评分(≤60分)、组织学分级(低分化)、腹腔淋巴结转移、skp2蛋白阳性表达和p27Kip1蛋白阴性表达是晚期胃癌患者预后的独立危险因素(P<0.05)。结论晚期胃癌组织中skp2蛋白阳性表达和p27Kip1蛋白阴性表达是晚期胃癌临床预后差的独立危险因素,可作为晚期胃癌治疗方案、预后评估等方面的有效指标。

Skp2及p27kip1在原发性胃癌组织的表达及对胃癌细胞增殖、凋亡的影响

目的探究S期激酶相关蛋白2(S-phase kinase associated protein 2,Skp2)及细胞周期素依赖的蛋白激酶抑制物(Cyclin dependent protein kinase inhibitor,p27kip1)在原发性胃癌组织的表达及si-Skp2对胃癌细胞增殖、凋亡和p27Kip1表达的影响。方法组织学实验:临床入组2018年12月~2021年12月唐山市开滦总医院林西医院归档的资料齐全完整的63例原发性胃癌患者,获得患者的癌组织和癌旁组织,通过qPCR对两组患者胃癌组织和胃癌旁组织Skp2和p27Kip1mRNA表达水平进行检测。细胞学实验,将人胃癌细胞SGC-7901分为对照组和si-Skp2组,对照组转染NC质粒,si-Skp2组转染si-Skp2质粒,CCK8法检测各组细胞24 h、48 h和72 h增殖能力,流式细胞分别分析两组细胞细胞存活、早期凋亡和晚期凋亡,Western blot检测两组细胞Skp2和p27kip1蛋白表达水平。结果组织学实验表明,相比于癌旁组织,癌组织中Skp2mRNA表达显著上升,p27Kip1表达显著降低,差异有统计学意义(P<0.01)。细胞学实验表明,与对照组相比,si-Skp2组细胞24 h、48 h和72 h细胞增殖能力显著降低;细胞存活显著降低、细胞晚期凋亡显著增加(P<0.01),细胞早期凋亡没有显著的统计学差异(P>0.05);Western blot实验表明si-Skp2组细胞Skp2表达显著降低,p27Kip1蛋白表达水平显著上调(P<0.01)。结论原发性胃癌组织中Skp2表达显著高表达,p27Kip1显著低表达,si-Skp2具有显著抑制胃癌细胞增殖,促进细胞晚期凋亡的作用,其机制与p27Kip1的调控相关。

S相激酶相关蛋白和P27kip1蛋白表达与胃癌临床病理特征的相关性研究

在本次研究中主要分析细胞5相激酶相关蛋白以及P27kip1与胃癌的临床关系。方法 本次研究中针对67例临床诊断为胃癌的患者,利用免疫组化S-P法检测Skp2和P27kip1蛋白的表达情况,结果 在胃癌患者中Skp2蛋白表达率达33.33%,而对于正常患者来说,胃组织Skp2蛋白表达率为10.73%,两组数据具有明显统计差异。除此之外,根据研究发现Skp2蛋白阳性表达率与患者的肿瘤大小、年龄,性别以及病灶位置无明显关系,但与患者的肿瘤分化程度具有紧密联系。Skp2与P27kip1的表达是呈现负相关关系的。结论 临床上Skp2异常表达会从一定程度上加速细胞周期转化,以促进胃癌症状发生,在胃癌发生中,泛素-蛋白酶体途径发挥重要作用。

p27kip1复制缺陷腺病毒重组体的构建与鉴定

目的 :构建含人细胞周期依赖激酶抑制剂p2 7kip1基因的重组腺病毒载体 ,为采用p2 7kip1cDNA防治肿瘤的研究奠定基础。方法 :将人p2 7kip1cDNA插入到穿梭质粒pACCMVPLPA的CMV启动子之下 ,即pAd p2 7kip1。后者与pJM17通过脂质体共转染 2 93细胞 ,经同源重组获得含人p2 7kip1cDNA的重组腺病毒Ad p2 7kip1。结果 :p2 7kip1cDNA成功地插入了pACCMVPLPA载体 ,以重组病毒基因组DNA为模板 ,同时扩增出了 2 75bp的p2 7kip1基因片段和 86 0bp的腺病毒骨架基因片段 ,证实了Ad p2 7kip1的正确性。病毒滴度为 1.2 4× 10 1 2 pfu ml。结论 :成功构建了携带人p2 7kip1基因的腺病毒Ad p2 7kip1,为采用p2 7kip1cDNA途径防治消化道肿瘤的在体。

p27Kip1基因shRNA表达质粒的构建鉴定及功能研究

目的构建细胞周期性激酶抑制剂p27Kip1的小发夹RNA(short hairpin RNA,shRNA)表达质粒,并观察其对牛角膜内皮细胞增殖能力的影响。方法设计有发夹状结构的3条p27Kip1-shRNA对应模板DNA序列,并构建无关序列HK-shRNA作为阴性对照。转入带有增强型绿色荧光蛋白(EGFP)和启动子U6的pGenSil-1质粒,构建重组质粒pGenSil-1/p27Kip1-1、pGenSil-1/p27Kip1-2、pGenSil-1/p27Kip1-3、pGenSil-1/HK。转化DH5α菌株,提取质粒行酶切及测序鉴定。以脂质体法将4个重组质粒分别导入牛角膜内皮细胞。转染后48h以Western blot法检测p27Kip1蛋白水平及MTT法检测各实验组和对照组细胞增殖情况。结果酶切及测序证实4个重组质粒均构建成功。3个实验组p27Kip1蛋白水平分别下降了66.41%、61.51%、71.32%,shRNA可显著促进牛角膜内皮细胞增殖。结论成功构建了针对p27Kip1的RNA干扰表达载体。

昆布多糖硫酸酯对PC-3细胞PTEN和P27kip1基因表达的影响

目的:研究昆布多糖硫酸酯(LAMS)对体外培养的非激素依赖型人前列腺癌细胞株PC-3的作用,以及对PC-3细胞PTEN和P27kip1基因表达的影响,并探讨其抗肿瘤的作用机制。方法:分别用0、50、100、200μg/ml浓度的LAMS作用于PC-3细胞,用WST-8法检测其对细胞生长的抑制作用,利用流式细胞术(FCM)分析细胞周期和凋亡的变化,用荧光显微镜观察PC-3细胞形态的变化,RT-PCR和Western印迹检测细胞增殖、凋亡相关基因PTEN和P27kip1mRNA及蛋白的表达。结果:LAMS能抑制PC-3细胞的增殖,呈时间-剂量效应;不同浓度LAMS诱导PC-3细胞出现剂量依赖性S期阻滞;LAMS作用于PC-3细胞后凋亡率增加,并出现凋亡的形态学改变,相关基因PTEN和P27kip1mRNA及蛋白的表达呈剂量依赖性增加。结论:LAMS能抑制体外PC-3细胞的生长,并促进其S期阻滞和凋亡,PTEN和P27kip1mRNA及蛋白的表达明显增加,可能是其抑制前列腺癌生长的机制之一。

P27kip1和cyclinE在子宫内膜癌中的表达及其意义

目的 探讨P2 7kip1、cyclinE的表达与子宫内膜癌发生发展的关系。 方法 用免疫组化方法检测P2 7kip1和cyclinE在 4 0例子宫内膜癌、10例子宫内膜不典型增生、2 0例正常子宫内膜组织中的表达。结果 P2 7kip1在正常子宫内膜、内膜不典型增生、子宫内膜癌中的表达率分别为 90 %、70 %、6 2 .5 % ,其中子宫内膜癌与正常子宫内膜差异有显著性 (P <0 .0 5 )。cyclinE表达阳性率子宫内膜癌组显著高于内膜不典型增生组和正常子宫内膜组 (P <0 .0 5 )。P2 7kip1表达与子宫内膜癌的组织学分级、手术分期有关 (P <0 .0 5 )。P2 7kip1与cyclinE表达呈负相关。 结论 P2 7kip1、cyclinE在子宫内膜癌发生中可能起一定作用 ,P2 7kip1还与子宫内膜癌的进展有关 ,并可能成为判断预后的有用指标。

Skp2和p27Kip1表达异常与乳腺癌发生及临床病理特征的相关性研究

目的从蛋白水平研究Skp2和p27Kip1表达异常与乳腺癌发生及临床病理特征的相关性。方法采用En Vision两步法检测30例乳腺正常组织,30例导管上皮不典型增生组织（ADH）、30例导管原位癌（DCIS）和56例浸润性导管癌（非特殊类型）（IDC）中Skp2和p27Kip1的表达水平,并分析Skp2和p27Kip1表达异常与乳腺癌发生及临床病理特征的关系。结果 1ADH组、DCIS组及IDC组的Skp2阳性率均高于正常对照组（P〈0.05,P〈0.01,P〈0.01）,IDC组和DCIS组高于ADH组（P〈0.01,P〈0.05）,IDC组又高于DCIS组（P〈0.01）。ADH组、DCIS组和IDC组p27kip1阳性率均低于正常对照组（P〈0.05,P〈0.01,P〈0.01）,IDC组和DCIS组均低于ADH组（P〈0.01,P〈0.05）,IDC组又低于DCIS组（P〈0.01）。2IDC伴淋巴结转移组Skp2阳性率显著高于DCIS淋巴结转移组（P〈0.05）;IDCⅢ级高于IDCⅠ-Ⅱ级（P〈0.01）。反之,p27kip1阳性率在IDC伴淋巴结转移组低于无淋巴结转移组（P〈0.05）;IDCⅢ级低于Ⅰ-Ⅱ级（P〈0.01）。结论 Skp2与p27Kip1异常表达与乳腺癌发生、病理分级和淋巴结转移有密切相关性。

p27kip1基因对食管癌细胞DNA复制及蛋白质合成的影响

目的 :研究p2 7kip1基因对人食管癌细胞EC -970 6的DNA复制及蛋白质合成的影响。方法 :重组体腺病毒Ad -p2 7kip1转染EC -970 6细胞 ,采用细胞生长计数、[3H] -TdR、[3H] -Leucine掺入法、流式细胞术 ,研究其对食管癌细胞DNA复制及蛋白合成的影响。结果 :Ad -p2 7kip1组细胞生长明显受抑 ,[3H] -TdR和 [3H ] -Leucine掺入量均明显减少 ,与对照组比较P <0 0 1;食管癌细胞的增殖明显受抑制。结论 :p2 7可有效抑制食管癌细胞的增殖活性 ,这与其抑制食管癌细胞DNA复制及蛋白质合成有关。

5-Aza-CdR对胃癌细胞系p27kip1基因异常甲基化的影响

目的探讨5-氮杂-2'-脱氧胞苷(5-Aza-CdR)对胃癌细胞系SGC7901的p27kip1基因异常甲基化及表达的影响。方法选择不同浓度的5-Aza-CdR处理体外培养的SGC7901细胞后,用MSP法检测用药前后细胞中p27kip1基因的甲基化状态;RT-PCR法检测用药前后细胞中p27kip1的mRNA及蛋白表达的变化。结果 p27kip1基因的甲基化状态得到了逆转,p27kip1基因的mRNA和蛋白表达得到增加。结论 SGC7901细胞中p27kip1基因的表达情况与其甲基化状态的改变有关。

p27kip1腺病毒重组体对人食管癌裸鼠移植瘤生长的抑制作用

背景:p27kip1是新近发现的一种抑癌基因,研究表明p27kip1基因转移能显著抑制食管癌和胃癌细胞生长,该基因疗法在体内实验中是否同样有效值得进一步研究。目的:研究p27kip1腺病毒重组体对人食管癌裸鼠移植瘤生长的抑制作用。方法:将携带人p27kip1基因的重组腺病毒载体导入人食管癌裸鼠移植瘤中,测定肿瘤生长抑制率,免疫组化方法检测移植瘤中p27kip1和生存素(survivin)的表达。结果:经p27kip1基因治疗的裸鼠,肿瘤生长抑制率达64.1%,移植瘤中p27kip1呈高表达,生存素呈低表达。结论:p27kip1腺病毒重组体能显著抑制人食管癌裸鼠移植瘤的生长,上调p27kip1和下调生存素的表达可能是其重要作用机制。