p27(kip1) immunoreactivity correlates with long-term survival in pleural malignant mesothelioma

BACKGROUND: Pleural malignant mesothelioma (PMM) is a rare and highly aggressive tumor, whose development is strictly related to occupational exposure to asbestos. The prognosis of PMM is generally poor (median survival, 4-12 months), but a few have a relatively long survival. The objective of this study was to evaluate the use of the cell cycle-related proteins p27(kip1) and MIB-1 as prognostic indicators of survival in PMMs. METHODS: Of 621 PMMs, the authors selected 27 cases with a relatively long-term survival (> 24 months) and a control group of 36 PMMs having a shorter (usual) survival (< 24 months). RESULTS: The expression of the p27(kip1) was significantly higher in the long-term survival group compared with the control (short survival) group (81.41% vs. 31.94%; P < 0.0001). The PMMs of epithelioid histotype had a significantly higher p27(kip1) immunoreactivity compared with those of biphasic type (59.24% vs. 38.94%; P = 0.02). In agreement with the data in the literature, the proliferative activity (as detected by MIB-1 immunoreactivity) was significantly higher in short than long survival PMMs (43.53% vs. 14.11%; P < 0.0001) and in the biphasic histotype than in the epithelioid type (43.19% vs. 26.02%; P = 0.006). CONCLUSIONS: The combined expression of high/low p27(kip1) and low/high Ki-67 values identified with 100% specificity and sensitivity long versus short survivors. p27(kip1) represents a reliable additional predictive factor for PMMs and a useful marker to identify patients having a more favorable prognosis.     

Prognostic significance of p27(kip1) protein expression and spontaneous apoptosis in patients with colorectal adenocarcinomas

Tumor cell apoptosis, proliferation and p27 expression using an in situ apoptosis detection kit, anti-Ki67 antibody and anti-p27 antibody were investigated in 171 colorectal adenocarcinoma specimens, together with the assessment of mutated p53 expression. No apparent association was observed among p27 expression, mutated p53 accumulation, the Ki67 labeling index and the apoptotic index (AI). In the multivariate analysis using the median values as the cut-off points (46.8% for p27 expression and 0.89% for AI), p27 expression was identified as an independent and significant predictor for overall survival. When the present series of patients were dichotomized by these cut-off points to categorize the cases into 4 subgroups, the patients in the group with low p27 expression and a low AI had the poorest prognosis. The assessment of p27 expression and AI therefore may prove valuable in identifying patients with colorectal adenocarcinoma who may have a poor prognosis.     

p27(kip1) protein expression correlates with survival in myxoid and round-cell liposarcoma.

PURPOSE: The p27(kip1) protein (p27) is a cyclin-dependent kinase inhibitor that has been shown to be an independent prognostic factor in a variety of human neoplasms. Low expression of p27 tends to occur in more aggressive neoplasms. The role of p27 as an independent prognostic factor in the spectrum of myxoid and round-cell liposarcomas has not been examined. MATERIALS AND METHODS: Forty-seven cases of myxoid and round-cell liposarcomas were examined. Clinicopathologic features and immunohistochemical expression of p27 and Ki-67 antigen were studied in all cases. Survival analysis was performed using the log-rank test and the Cox multivariate regression model. RESULTS: The male:female ratio was 1. 4:1, and the mean age at diagnosis was 45 years. The tumors were located in the lower extremities (94%) and retroperitoneum (6%). The median tumor size was 13.5 cm. The median follow-up was 6.3 years, and the overall 5- and 10-year survival rates were 76% and 67%, respectively. Low expression of p27 was identified in 34 cases (72%) and correlated with decreased metastasis-free (P =.026) and overall survival (P =.008). In a multivariate analysis, only round-cell differentiation and low expression of p27 independently predicted decreased metastasis-free and overall survival. CONCLUSION: p27 expression predicts the clinical behavior of myxoid and round-cell liposarcomas, even in neoplasms with few or no round-cell differentiation.     

A survival-stratification model of human colorectal carcinomas with beta-catenin and p27kip1

BACKGROUND: The stabilization and nuclear translocation of beta-catenin are early events in the majority of sporadic colorectal carcinomas (CRC). beta-catenin up-regulates c-Myc and cyclin D1, which antagonize the association of the cyclin-dependent kinase (Cdk) inhibitor, p27(kip1), with Cdk2, thus allowing cell cycle progression through G1 to S-phase. Lack of p27 is a significant predictor of poor survival in a series of 136 CRC specimens. A combination of molecules in the same pathway may be a better prognostic factor. METHODS: The expression of beta-catenin, c-Myc, and cyclin D1 in relation to patients' survival and clinicopathologic parameters in the same series was evaluated by immunohistochemistry. RESULTS: Intense nuclear overexpression of beta-catenin, but not a lack of cell membrane or cytoplasmic expression, is a significant predictor of poor survival by both univariate (P = 0.0029) and multivariate analyses (P = 0.004, risk ratio =3.8), suggesting that beta-catenin is retained in the nucleus to function as an oncogene. None of the patients with high nuclear beta-catenin and low p27 expression survived 5 years or more whereas 65% of patients with all other combinations of the two markers survived (P < 0.0001). This combination is also a significant and independent prognostic factor (P = 0.001; risk ratio = 9.7). Overexpression of c-Myc is associated with higher mortality rates, but the expression of cyclin D1 has no prognostic significance. CONCLUSIONS: The combined expression of beta-catenin and p27 can stratify patients into markedly different survival groups, possibly via their antagonistic effects on metastasis promotion.     

Jab1与p27kip1蛋白在食管鳞癌中的表达及相互关系

背景与目的:p27kip1作为细胞周期负性调节因子,主要抑制CyclinE-CDK2和CyclinD-CDK4等激酶复合物的活性,从而实现对细胞调控功能.Jab1和p27kip1的表达呈负相关,与细胞的增殖呈正相关,从而促进肿瘤发展.本研究旨在分析食管鳞癌中Jab1和p27kip1蛋白的表达水平及其与临床病理的关系,以探讨其在食管鳞癌发生、发展和预后中的作用.方法:采用免疫组化二步法及Western blot法测定60例食管鳞型细胞癌(ESCC)、20例癌旁正常食管组织(NET)(距癌旁安全切缘5.0 cm以上)中Jab1和p27kip1蛋白的表达.结果:Jab1蛋白阳性表达率在NET中为20%,与ESCC组织中的78.3%相比,差异有统计学意义(P<0.01).p27kip1蛋白阳性表达率在NET中为90%,与ESCC组织中的38%相比,差异有统计学意义(P<0.01).ESCC中Jab1的过表达与肿瘤分化程度及淋巴结转移显著相关(P<0.05),p27kip1的表达与肿瘤分化程度显著相关(P<0.05),Jab1的表达与p27kip1的表达呈负相关(r=-0.334,P<0.05).结论:Jab1作为p27kip1的负性调控分子,可能参与ESCC的发生、发展过程,联合检测Jab1及p27kip1的表达有助于综合评估ESCC的生物学行为.     

乳腺癌表达细胞周期蛋白依赖性激酶抑制物p27kip1的预后意义

研究ｐ２７＾ｋｉｐｌ在乳腺癌组织中的表达水平,及其与生物学行为的关系和对预后的作用。方法以免疫组化法检测１８１例乳腺癌组织ｐ２７＾ｋｉｐｌ蛋白表达水平,其中９１例进行了凋亡指数、凋亡相关蛋白ｂｃｌ－２、ｂａｘ的测定,另有１０６例检测了ｐ２１＾ＷＡＦ１／ＣＩＰＩ、ｐ５３、ｍｄｍ２蛋白表达水平。结果本组１８１例中,ｐ２７＾ｋｉｐｌ蛋白阳性１２５例,占６９．１％;低表达者１２１例,占６６．９％;高表达者     

Anomalous p27kip1 expression in a subset of malignant gliomas

p27^Kip1 (p27) expression was immunohistochemically investigated in 28 astrocytic tumors, and compared with the cell proliferation index (MIB-1 staining index). Normal rat brains and surgical specimens from human nonneoplastic brain lesions were used as controls. In the rat brains, the astrocytes were exclusively p27-positive. The reactive astrocytes in various disease processes sometimes lacked p27 expression. The distribution of p27-positive cells was uniform in low-grade astrocytomas and heterogeneous in high-grade tumors. Double staining of p27 and MIB-1 showed a reciprocal pattern in most cases. The frequency of p27 expression was inversely correlated with MIB-1 staining index and tumor grade. However, several malignant gliomas showed high p27 expression in spite of high MIB-1 staining indices. In such cases, MIB-1-positive cells were occasionally p27-positive. In this paper we discuss the etiology of the anomalous p27 expression in a subset of malignant gliomas.     

Clinicopathologic significance of an immunohistochemical expression of p27 in scirrhous carcinoma of the breast

BACKGROUND: Scirrhous carcinoma has been known to have more aggressive biological behavior than other histologic subtypes of invasive ductal carcinoma of the breast. The significance of expression of p27kip1, which is thought to be a tumor suppressor gene, in breast carcinoma remains controversial. The aim of the current study was to clarify clinicopathologic significance of scirrhous carcinoma of the breast with special reference to p27 expression. METHODS: Clinicopathologic features including immunohistochemical expression of p27 were compared between scirrhous carcinoma (n=42) and non-scirrhous invasive ductal carcinoma (papillotubular and solid-tubular carcinoma, n=63) of the breast. RESULTS: The proportion of pathologic lymph node metastasis among scirrhous carcinomas was significantly higher than that among carcinomas of other histologic types (papillotubular or solid-tubular carcinomas, p=0.029). The proportion of strong expression of p27 among scirrhous carcinomas was significantly lower than that among tumors of other histologic types (p<0.0001). CONCLUSIONS: Biological behavior of scirrhous carcinoma was found to be aggressive. The aggressiveness and poor cellular differentiation of scirrhous carcinoma of the breast might be related to low p27 expression.     

宫颈癌P27kip1基因突变、缺失及表达

目的　探讨p2 7蛋白在宫颈癌中表达的意义及p2 7基因缺失、突变在宫颈癌发生中的作用。方法　采用链霉菌抗生素蛋白 -过氧化酶 (S -P)免疫组化法及聚合酶链反应 -单链构象多态性 (PCR -SSCP)分析法分别检测宫颈癌中p2 7基因的蛋白表达及其两个外显子的缺失、突变。结果　p2 7蛋白表达 ,18例正常宫颈上皮组织均为高表达 ,48例宫颈癌组织中 ,19% ( 9/48)高表达 ,81% ( 39/48)低表达 ,宫颈癌中高表达率明显低于正常宫颈组织 (P <0 .0 5 ) ;宫颈癌的分化程度中 ,Ⅰ级高表达 5 0 % ( 5 /10 )明显高于Ⅱ级 13% ( 3/2 4)及Ⅲ级 7% ( 1/14 ) (P <0 .0 5 ) ;伴有淋巴结转移的高表达4% ( 1/2 3) ,不伴淋巴结转移的高表达 32 % ( 8/2 5 ) ,差异有显著性 (P <0 .0 5 ) ;p2 7基因缺失、突变分析 ,17例宫颈癌及 8例正常宫颈组织均未发现一例外显子Ⅰa、Ⅰb及外显子Ⅱ缺失、突变。结论　p2 7与宫颈癌的发生发展、分化程度及淋巴结转移有关 ;宫颈癌中未发现p2 7基因缺失与突变 ;对p2 7蛋白进行检测为诊断宫颈癌及临床综合治疗提供参考。     

乳腺癌中PTEN蛋白表达及其与p27kip1和cyclin D1表达的相关性

目的 探讨抑癌基因PTEN蛋白在人乳腺癌中的表达情况,及其与抑癌基因p27^kiP1、癌基因cyclin D1表达的相关性。方法 应用免疫组织化学染色S-P法,检测6l例乳腺癌组织石蜡切片中PTEN蛋白、p27^kiP1和cyclin D1蛋白的表达情况,比较PTEN蛋白表达与临床病理指标的关系,及其与p27^kiP1、cyclin D1蛋白表达的相关性。结果 PTEN蛋白表达定位于细胞质。PTEN蛋白阴性占6．6％(4／61),表达减低者占41．0％(25／61),阳性表达者占52．5％(32／61)。PTEN与淋巴结状态、ER状态及局部复发、远处转移相关。单因素生存分析显示,PTEN蛋白高表达组的5年生存率(87．5％)高于低表达组(58．6％,P=0．0101)。PTEN蛋白表达与p27^kiP1、cyclin D1表达未显示有明显相关性。结论 乳腺癌患者PTEN蛋白低表达与预后不良有关,PTEN对乳腺癌肓一定的预后价值。在人乳腺癌中,p27^kiP1和cvclin D1可能不是PTEN的主要下游基因。     

Expression of the HER family mRNA in breast cancer tissue and association with cell cycle inhibitors p21(waf1) and p27(kip1)

BACKGROUND: The HER family of the receptor tyrosine kinases epidermal growth factor receptor (EGFR), HER2, HER3 and HER4 are involved in the pathogenesis of many human malignancies. Although there is extensive literature on the expression of single HER-2 and EGFR receptors in breast cancer, little is known concerning the simultaneous expression at the mRNA level of these four receptors in human breast tissue and their influence in downstream signaling pathways that control cell cycle and proliferation. MATERIALS AND METHODS: The mRNA expression pattern of the four HER-receptors has been investigated and correlated with the expression of the cyclin-dependent kinase (CDK) inhibitors p21(Waf1) and p27(Kip1) in 67 breast cancer specimens. RESULTS: A positive correlation between HER-3 and HER-4 mRNA levels and a negative correlation between HER-2 and HER-3 was found. Compared to normal breast tissue, all four receptors were overexpressed in breast tumors and the strongest overexpression was found for HER-3 (p = 0.001). HER-4 expression was inversely related to histopathological grading (HPG), suggesting that elevated HER-4 mRNA expressions could be a biological marker of a more differentiated phenotype. The expression of p21(Waf1) protein was higher in HER-2-negative tumors, compared to HER-2-positive breast carcinomas. Compared to normal breast tissue, p21delta, the 19 kDa degraded form of p21 protein, was markedly expressed in breast cancer (p < 0.001). Conversely, p27(Kip1) was positively associated with HER-2 receptor and inversely associated with HER-3. CONCLUSION: The HER family members are overexpressed in breast cancer. Complex patterns of HER family expression were observed and the effect on cell cycle regulation was dependent on that pattern.     

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。     

P27(kip1) down-regulation is associated with trastuzumab resistance in breast cancer cells

Trastuzumab (Herceptin) is a recombinant humanized monoclonal antibody directed against HER-2. The objective response rate to trastuzumab monotherapy is 12-34% for a median duration of 9 months, by which point most patients become resistant to treatment. We created two trastuzumab-resistant (TR) pools from the SKBR3 HER-2-overexpressing breast cancer cell line to study the mechanisms by which breast cancer cells escape trastuzumab-mediated growth inhibition. Both pools maintained her-2 gene amplification and protein overexpression. Resistant cells demonstrated a higher S-phase fraction by flow cytometry and a faster doubling time of 24-36 h compared with 72 h for parental cells. The cyclin-dependent kinase inhibitor p27(kip1) was decreased in TR cells, and cyclin-dependent kinase 2 activity was increased. Importantly, exogenous addition of p27(kip1) increased trastuzumab sensitivity. Additionally, resistant cells displayed heightened sensitivity to the proteasome inhibitor MG132, which induced p27(kip1) expression. Thus, we propose that trastuzumab resistance may be associated with decreased p27(kip1) levels and may be susceptible to treatments that induce p27(kip1) expression.     

乳腺癌组织中PTEN和p27kip1蛋白的表达及其相互关系

目的:探讨PTEN和p27kip1在乳腺癌组织中的表达规律及其相互关系。方法:采用免疫组化SP法检测64例乳腺癌组织中PTEN和p27kip1蛋白的表达。结果:乳腺癌组织PTEN(34/64)和p27kip1(33/64)蛋白表达显著低于正常乳腺组织(15/15),P值分别为0·0082和0·0078。有腋淋巴结转移、远处转移及ER阴性组PTEN表达分别为13/33、3/11和16/38,明显低于无腋淋巴结转移(21/31)、无远处转移(31/53)和ER阳性组(18/26),P值分别为0·0240、0·0063和0·03475。p27kip1在乳腺癌有腋淋巴结转移、远处转移及ER阴性组的表达分别为7/33、2/11和8/38,明显低于无腋淋巴结转移(15/31)、无远处转移(20/53)和ER阳性组(14/26),P值分别为0·0230、0·0440和0·0071。两者表达均与肿瘤大小无关。两种蛋白表达水平具有显著的相关性,P=0·0041。结论:PTEN、p27kip1表达异常与乳腺癌转移及恶性程度密切相关,两种基因蛋白表达强度一致,显示其在乳腺癌演进中具有协同作用。