乳腺浸润性导管癌中cyclinD1 、p57 KIP2的表达及意义

 目的 研究cyclinD1、p57^KIP2在乳腺浸润性导管癌（IDC）中的表达及意义。方法 采用免疫组织化学SP法检测64例113（2、15例乳腺导管内癌（DCIS）和15例癌旁正常乳腺组织中cyclinD1、p57 ^KIP2的表达。结果 cyclinD1、p57 ^KIP2阳性表达率在IDC与在乳腺不同组织之间、腋窝淋巴结有无转移之间差异均有显著性（P≤0．05，P〈0．01）；cyclinD1阳性表达率与IDC组织学分级有关（P〈0．01）；cyclinD1与p57 ^KIP2之间阳性表达率呈负相关（P〈0．01）。结论 cyclinD1与p57 ^KIP2共同参与了乳腺癌的发生发展过程。cyclinD1异常表达是乳腺癌发生的早期事件。联合检测cyclinD1及p57 ^KIP2对预测乳腺癌淋巴结转移有重要意义。     

胃癌中Cks1、P27Kip1、Skp2蛋白表达相关性及其意义

目的:探讨Cks1在胃癌发生及Skp2调节P27Kip1降解过程中的作用。方法:应用流式细胞术检测正常胃黏膜、胃不典型增生组织及胃癌组织中Cks1、P27Kip1、Skp2蛋白的表达。结果:由正常胃黏膜、胃不典型增生组织到胃癌中Cks1、Skp2的表达均呈上升趋势(P<0.05),P27Kip1表达则呈下降趋势(P<0.05)。胃癌中Cks1、Skp2表达均与P27Kip1表达呈负相关(r=-0.649,P<0.05;r=-0.732,P<0.05);而Cks1蛋白表达与Skp2蛋白无相关性(P>0.05)。胃癌中Cks1表达与肿瘤分化程度相关(P<0.05),而与肿瘤浸润深度、淋巴结转移及临床分期不相关(P>0.05)。结论:Cks1可能参与胃癌的发生;胃癌中Cks1可能参与Skp2调节P27Kip1泛素化的降解过程。     

乳腺癌中cyclinD2 、CDK4 的表达及其临床意义

 目的 研究乳腺癌组织中细胞周期蛋白D2（cyclinD2）、细胞周期蛋白依赖性激酶4（cyclin-dependentkinase4,CDK4）的表达,探讨它们与p27^kip1蛋白表达、与临床病理指标的关系及其预后意义。方法 应用免疫组化SP法,检测96例乳腺癌、18例癌旁正常乳腺组织石蜡切片中cyclinD2、CDK4的表达,比较它们与p27 ^kip1蛋白表达、与临床病理学指标之间的关系。结果 ①96例乳腺癌组织中cyclinD2、CDK4和p27^kip1表达率分别为41.7％、54．2％和38．5％,与正常乳腺组织相比有显著性差异（P〈0．001）。②cyclinD2、CDK4的表达与乳腺癌的组织学分级,核分裂数有关（P〈0．001）,和局部复发有关（P〈0．05）,而与患者年龄、肿瘤大小、组织类型无关（P〉0．05）,CDK4的表达与乳腺癌的淋巴结转移,雌激素受体状态也有密切关系（P〈0．01）。③p27^kip1的表达缺失,与肿瘤大小、组织学分级,核分裂数,有无淋巴结转移以及局部复发均有关系（P〈0．05）,而且p27 ^kip1的表达与eyelinD2、CDK4的表达呈显著负相关（P〈0．叭）。结论 cyclinD2和CDK4的表达与乳腺癌的发生、发展有关,而p27 ^kip1的表达缺失和CDK4的异常表达与乳腺癌的侵袭、转移及复发有关,可作为判断乳腺癌生物学行为和预后的重要指标。     

宫颈腺癌组织Skp2与p27kip1表达及临床意义

目的：研究宫颈腺癌组织中S期激酶相关蛋白2（Skp2）和细胞周期调控因子p27^kipl的表达及其临床意义。方法：采用组织微阵列技术结合免疫组化（二步法）检测106例宫颈腺癌组织和22例慢性宫颈炎组织中Skp2和p27^kipl的表达。结果：106例宫颈腺癌组织Skp2阳性表达率为67．9％，显著高于慢性宫颈炎组织（P〈0．01）；p27^kipl阳性表达率为58．5％，明显低于慢性宫颈炎组织（P〈0．05）。Skp2在宫颈腺癌的病理分级中，G2、G3组阳性表达率均明显高于G1组（P〈0．05）。Skp2和p27^kipl表达与宫颈腺癌组织学类型有明显相关性，子宫内膜样腺癌Skp2阳性表达率明显高于其他类型宫颈腺癌（P〈0．05），透明细胞腺癌p27^kipl阳性表达率明显低于其他类型宫颈腺癌（P〈0．05）。Skp2和p27^kipl阳性表达率无明显负相关。结论：Skp2高表达与p27^kipl低表达在宫颈腺癌的发生、发展中起重要作用，Skp2高表达可作为宫颈腺癌恶性化的分子指标；采用组织微阵列进行Skp2和p27^kipl免疫组化检测具有可靠性和实用性。     

p57 KIP2 、cyclin D1 和cyclin E 在宫颈鳞癌中的表达及意义

 目的 探讨p57^KIP2、cyclin D1及cyclin E蛋白在宫颈癌发生、发展中的作用。方法 用免疫组织化学SP法检测100例宫颈鳞癌、60例宫颈上皮内瘤变和30例正常宫颈鳞状上皮组织中p57 KIP2、cyclin D1和cyclin E蛋白的表达情况。结果 cyclin D1、cyclin E蛋白在宫颈SCC与NE、CIN与NE组织中阳性表达率之间比较、cyclin E蛋白在宫颈SCC与CIN组织中阳性表达率之间比较,差异均有显著性（P〈0．01）;cyclin D1与cyclin E之间的表达呈正相关（P〈0．01）;三者表达均与组织学分级、淋巴结转移、患者年龄无关（P〉0．05）。结论 p57 ^KIP2、cyclin D1及cyclin E蛋白共同参与了宫颈癌的发生发展。cyclin D1和cyclin E蛋白高表达可能是宫颈组织恶变的重要生物学标志,cyclin E异常表达是宫颈癌发生的早期事件。     

结直肠癌中survivin 、caspase-3 、p21WAF1的蛋白表达及其意义

 目的 探讨结直肠癌中survivin、caspase-3和p21^WAF1的蛋白表达与临床病理参数的联系以及survivin与caspase-3和p21^WAF1蛋白表达之间的关系。方法 采用免疫组织化学SP方法检测15例正常结直肠粘膜和62例结直肠腺癌标本中survivin、caspase-3和p21^WAF1的蛋白表达。结果 结直肠腺癌与正常结直肠粘膜比较,survivin、caspase-3和p21^WAF1的蛋白表达差异均有显著性（P〈0.05）。survivin和caspase-3的蛋白表达与淋巴结转移无明显相关（P〉0.05）;而与分化程度均显著相关（P〈0.05）。survivin蛋白与Dukes分期相关（P〈0.05）;但caspase-3的蛋白表达与Dukes分期无关（P〉0.05）。p21^WAF1蛋白表达与分化程度、淋巴结转移和Dukes分期均显著相关（P〈0.05）。survivin蛋白分别与caspase-3、p21^WAF1蛋白表达之间均呈显著负相关（P〈0.01）。结论 survivin、caspase-3和p21^WAF1蛋白在结直肠癌的发生和进展中都起着重要的作用。p21^WAF1基因与结直肠癌的恶性进展显著相关,此结论鲜见报道。     

Skp2、p27Kip1在胆囊癌组织中的表达及其临床意义

目的探讨Skp2、p27Kip1在胆囊癌及癌旁组织中的表达情况及与其临床病理特征的关系。方法采用免疫组织化学PV6000二步法,检测Skp2、p27Kip1在78例胆囊癌及癌旁组织中的表达情况,并应用SPSS13.0统计软件分析2种生物指标与胆囊癌临床参数的关系。结果 Skp2与p27Kip1在胆囊癌中的阳性表达率分别为59.0%和39.7%,在癌旁组织中为25.0%和70.0%,胆囊癌中Skp2、p27Kip1阳性表达率均高于胆囊癌旁组织(P均<0.05)。Skp2表达与Nevin分期、分化程度及坏死情况相关,Nevin分期高、分化程度低及伴有坏死的患者Skp2表达高(P均<0.05)。p27Kip1阳性表达与患者Nevin分期、神经侵犯及坏死情况呈负相关性,Nevin分期早、无神经侵犯或不伴坏死患者p27Kip1表达水平高(P均<0.05)。相关性检验显示Skp2与p27Kip1两者间无相关性(P>0.05)。结论 Skp2、p27Kip1均与胆囊癌的发生发展有一定关系,可能成为胆囊癌新的临床诊断和监测预后的指标.     

p^27Kip1和细胞周期蛋白D1在胃癌中的表达及其预后意义

目的：研究p^27Kip1、细胞周期蛋白D1（cyclinD1)在胃癌组织中的表达水平以及与生物学行为的关系和对预后评价的意义。方法：以免疫组化方法检测92例胃癌组织中p^27Kip1、 cyclinD1蛋白的表达水平。结果：本组92例胃癌中,p^27Kip1蛋白阳性39例,占42．4％;cyclinD1蛋白表达阳性44例,占47．8％;胃癌组织中,p^27Kip1蛋白水平与胃壁浸润深度、TNM分期、病理组织学分级、区域淋巴结转移均相关（P＜0．05）;cyclinD1蛋白表达与病理组织学分级负相关（P＜0．05）;p^27Kipl与cyclinD1蛋白阳性表达显著相关（P＜0．05）;单变量生存分析结果,p^27Kip1高表达组三年、五年生存率分别为77．1％、57．8％,明显高于低表达组的33．7％、26．3％（P＝0．007）,多变量分析显示,p^27Kip1是一个独立的预后指标（P＝0．0003）。结论：p^27Kip1可作为反映肿瘤恶性表型的指标,对胃癌预后具有一定的价值;cyclin1 D1是胃癌发生、发展过程中早期的分子事件;p^27Kip1在胃癌进展中起着比cyclin D1更重要的作用。     

p57kip2 、Cyclin E 在脑胶质瘤中的表达及临床意义

 目的 探讨p57^kip2皿蛋白、Cyclin E蛋白在人脑胶质瘤表达情况及其临床意义。方法 采用免疫组织化学SP法检测p57 ^kip2、Cyclin E在46例胶质瘤和10例正常脑组织中的表达。结果 在46例胶质瘤中，p57 ^kip2蛋白阳性率为34．8％(16／46)，显著低于正常脑组织(70％)(P<0．05)。低度恶性(Ⅰ～Ⅱ)、高度恶性(Ⅲ～Ⅳ级)及两年生存时间组别间差异有显著性(P<0．01)。Cyclin E蛋白阳性率为58．6％(27／46)，显著高于正常脑组织(20％)(P<0．05)。脑胶质瘤不同恶性程度及两年生存时间组别间差异有显著性(P<0．05)。p57 ^kip2蛋白的表达与Cyclin E蛋白的表达密切相关(rn=-0．359)。结论 p57 ^kip2蛋白和Cyclin E蛋白在脑胶质瘤的发生、发展中起重要作用。且与肿瘤的分化程度、患者预后密切相关。     

胃癌中p16,p27kip1和CDK4表达的比较及其意义

目的 研究胃癌组织中p16、p27^kip1蛋白和细胞周期依赖性激酶4（cyclin—dependent kinase4，CDK4）的表达，探讨它们与胃癌临床病理特征的关系及其对预后的影响。方法 应用免疫组化S-P法，检测120例胃癌，20例胃粘膜非典型增生和30例正常胃粘膜组织切片中p16和p27^kip1和CDK4、PCNA的表达，分析它们与临床病理参数的关系。结果 120例胃癌中p16，p27^kip1和CDK4，PCNA蛋白的表达率分别为43．3％，52．5％和46．7％，70．0％，与正常胃粘膜和非典型增生相比有显著性差异（P〈0．01）。p16和p27^kip1的表达缺失与胃癌的分化程度、局部淋巴结转移和临床TNM分期有密切关系（P〈0．05，P〈0．01）。CDK4、PCNA的高表达和胃癌的淋巴结转移和临床TNM分期有密切关系（P〈0．01）。胃癌中p16、p27^kip1的表达和CDK4、PCNA的表达呈负相关（P〈0．01），而p16和p27^kip1的表达、CDK4和PCNA的表达呈正相关（P〈0．01）。结论 CDK4、PCNA的高表达和p16、p27^kip1的表达缺失与胃癌的发生以及侵袭和转移有关，可作为判断胃癌病情和预后的重要指标。     

Prognostic implication of p27Kip1, Skp2 and Cks1 expression in renal cell carcinoma: a tissue microarray study

Background

p27^Kip1 plays a major role as a negative regulator of the cell cycle. The regulation of p27^Kip1 degradation is mediated by its specific ubiquitin ligase subunits S-phase kinase protein (Skp) 2 and cyclin-dependent kinase subunit (Cks) 1. However, little is known regarding the prognostic utility of p27^Kip1, Skp2 and Cks1 expression in renal cell carcinoma.

Methods

Immunohistochemistry was performed for p27^Kip1, Skp2 and Cks1 in tissue microarrays of 482 renal cell carcinomas with follow-up. The data were correlated with clinicopathological features. The univariate and multivariate survival analyses were also performed to determine their prognostic significance.

Results

Immunoreactivity of p27^Kip1, Skp2 and Cks1 was noted in 357, 71 and 82 patients, respectively. Skp2 and Cks1 expression were not noted in chromophobe cancers. A strong correlation was found between Skp2 and Cks1 expression (P < 0.001), both of which were inversely related to p27^Kip1 levels (P = 0.006 and P < 0.001), especially in primary and clear-cell cancers. Low p27^Kip1 expression and Skp2 expression were correlated with larger tumor size and higher stage, as well as tumor necrosis. Cks1 expression was only correlated with tumor size. In univariate analysis, low p27^Kip1 expression, Skp2 and Cks1 expression were all associated with a poor prognosis, while in multivariate analysis, only low p27^Kip1 expression were independent prognostic factors for both cancer specific survival and recurrence-free survival in patients with RCC.

Conclusion

Our results suggest that immunohistochemical expression levels of p27^Kip1, Skp2 and Cks1 may serve as markers with prognostic value in renal cell carcinoma.     

The expression of the ubiquitin ligase subunit Cks1 in human breast cancer

Introduction  

Loss of the cell-cycle inhibitory protein p27^Kip1 is associated with a poor prognosis in breast cancer. The decrease in the levels of this protein is the result of increased proteasome-dependent degradation, mediated and rate-limited by its specific ubiquitin ligase subunits S-phase kinase protein 2 (Skp2) and cyclin-dependent kinase subunit 1 (Cks1). Skp2 was recently found to be overexpressed in breast cancers, but the role of Cks1 in these cancers is unknown. The present study was undertaken to examine the role of Cks1 expression in breast cancer and its relation to p27^Kip1 and Skp2 expression and to tumor aggressiveness.     

Mutant B-RAF signaling and cyclin D1 regulate Cks1/S-phase kinase-associated protein 2-mediated degradation of p27Kip1 in human melanoma cells

Levels of cyclins and cyclin-dependent kinase (Cdk) inhibitors are tightly controlled during normal cell proliferation and are frequently dysregulated in cancerous cells. In melanoma, cyclin D1 is highly expressed and downregulation of the Cdk inhibitor, p27(Kip1), is associated with a poor prognosis. Mutant B-RAF is frequently expressed in melanoma and overrides growth factor and matrix adhesion control of cyclin D1 and p27(Kip1) levels in human melanocytes. Here, we demonstrate that p27(Kip1) expression is regulated by multiple mechanisms in melanoma cells. B-RAF regulates p27(Kip1) mRNA abundance independently of cyclin D1. Additionally, B-RAF and cyclin D1 control the levels of S-phase kinase-associated protein 2 (Skp2) that directs ubiquitin-mediated proteolysis of p27(Kip1). The cofactor for Skp2, Cdc kinase subunit 1 (Cks1) controls levels of Skp2 in melanoma cells and acts jointly with Skp2 to regulate p27(Kip1) levels. Importantly, expression of Cks1 is regulated by B-RAF and cyclin D1 at the mRNA level. Reduced Cks1 or Skp2 expression and enhanced p27(Kip1) levels inhibit melanoma cell growth. In summary, p27(Kip1) expression in melanoma is regulated by B-RAF at the mRNA level, and via B-RAF and cyclin D1 control of Cks1/Skp2-mediated proteolysis.     

The prognostic impact of the ubiquitin ligase subunits Skp2 and Cks1 in colorectal carcinoma

BACKGROUND: Loss of the cell-cycle inhibitory protein p27Kip1 is associated with poor prognosis in colorectal carcinoma. The decrease in p27Kip1 levels is the result of increased proteasome-dependent degradation, mediated and rate-limited by its specific ubiquitin ligase subunits S-phase kinase protein (Skp) 2 and cyclin-dependent kinase subunit (Cks) 1. Recently, Skp2 and Cks1 expression were found to be increased in some colorectal carcinomas, but their potential role as prognostic markers for survival is unknown. The present study was undertaken to assess the prognostic value of both Skp2 and Cks1 in colorectal carcinoma. MATERIALS AND METHODS: The expression of Skp2, Cks1, and p27Kip1 was examined by immunohistochemistry using highly specific antibodies on formalin-fixed, paraffin-embedded tissue sections from 80 patients with colorectal carcinoma. RESULTS: Overexpression of Skp2 and Cks1 strongly correlated with loss of p27Kip1 and loss of tumor differentiation. A significant decrease in overall survival was observed in patients expressing high Skp2 or Cks1 levels, and in particular, patients with Stage II and III disease. Each protein provided significant additional prognostic information to that given by disease stage, tumor grade, or p27Kip1 expression. CONCLUSIONS: Results suggest that overexpression of Skp2 or Cks1 is strongly associated with poor prognosis and may thus be used as prognostic markers for overall survival in colorectal carcinoma.     

Alterations in the expression of the cell cycle regulatory protein cyclin kinase subunit 1 in colorectal carcinoma

BACKGROUND: Low levels of p27(Kip1) are associated with high aggressiveness and poor prognosis in various malignancies, including colorectal carcinoma. The authors showed that S phase kinase protein 2 (Skp2), the specific ubiquitin ligase subunit that targets p27(Kip1) for degradation, was overexpressed and was inversely related to p27(Kip1) levels in patients with colorectal carcinoma. The essential role of cyclin kinase subunit 1 (Cks1) in Skp2-dependent p27 degradation was recently discovered, but its role in human malignancies is unknown. METHODS: Quick-frozen colorectal tumor samples from 30 patients were separated by electrophoresis on sodium dodecyl sulfate-polyacrylamide gels, transferred to nitrocellulose, and probed with highly specific monoclonal antibodies directed against Cks1, Skp2, and p27(Kip1). The expression of Cks1 was also examined by immunohistochemistry using formalin-fixed, paraffin-embedded tissue sections from the same patients. RESULTS: A strong correlation was found between Cks1 levels and Skp2 expression and loss of tumor differentiation. A significant inverse relation was also observed between levels of Cks1 and p27(Kip1) and overall survival. CONCLUSIONS: The results of the current study suggest that increased expression of Cks1 may have an important causative role in decreasing levels of p27 in patients with aggressive colorectal carcinoma.     

Identification of small molecule inhibitors of p27Kip1 ubiquitination by high‐throughput screening

Dysregulation of p27^Kip1 due to proteolysis that involves the ubiquitin ligase (SCF) complex with S‐phase kinase‐associated protein 2 (Skp2) as the substrate‐recognition component (SCF^Skp2) frequently results in tumorigenesis. In this report, we developed a high‐throughput screening system to identify small‐molecule inhibitors of p27^Kip1 degradation. This system was established by tagging Skp2 with fluorescent monomeric Azami Green (mAG) and CDK subunit 1 (Cks1) (mAGSkp2–Cks1) to bind to p27^Kip1 phosphopeptides. We identified two compounds that inhibited the interaction between mAGSkp2–Cks1 and p27^Kip1: linichlorin A and gentian violet. Further studies have shown that the compounds inhibit the ubiquitination of p27^Kip1 in vitro as well as p27^Kip1 degradation in HeLa cells. Notably, both compounds exhibited preferential antiproliferative activity against HeLa and tsFT210 cells compared with NIH3T3 cells and delayed the G₁ phase progression in tsFT210 cells. Our approach indicates a potential strategy for restoring p27^Kip1 levels in human cancers.