Significance of histone methyltransferase SETDB1 expression in colon adenocarcinoma

This study investigated the clinical implications of SETDB1 (also known as KMT1E) in human colon adenocarcinoma. Expression levels of SETDB1 proteins were analyzed by immunohistochemistry staining, and tissue microarrays were used to examine expression profiles in human patients. Our results revealed that SETDB1 protein expression was significantly higher in tumor tissue than in normal tissue for the breast, colon, liver, and lung (p < 0.05). Moreover, an analysis with SurvExpress software suggested that elevated expression of SETDB1 mRNA was significantly associated with the overall survival of colon adenocarcinoma patients (p < 0.05); and additional analysis involving 90 paired samples of colon adenocarcinoma tissue and normal tissue revealed that SETDB1 protein expression was 82% higher in cancerous cells (p < 0.001). High SETDB1 expression was also found to be significantly correlated with histological grade (p = 0.005), TNM stage (p = 0.003), T‐class/primary tumor (p = 0.001), and N‐class/regional lymph nodes (p = 0.017); and Kaplan–Meier survival curves indicated that SETDB1 protein expression was significantly associated with poor survival. Finally, univariate analysis demonstrated that SETDB1 protein expression was related to TNM stage (p = 0.004) and SETDB1 score (p = 0.001), whereas multivariate analysis showed that the influence of SETDB1 on overall colon adenocarcinoma survival was independent from other risk factors. Taken together, our results suggest that the SETDB1 protein could serve as a clinical prognostic indicator for colon adenocarcinoma.     

Up-regulated expression of Notch1 and Jagged1 in human colon adenocarcinoma

Deregulated expression of Notch molecules is observed in many malignant tumors, however, the expression of Notch1 and Jagged1 in colon adenocarcinoma is still unknown. This study is to investigate the expression of Notch1 and Jagged1 in human colon adenocarcinoma. Sixty-five human colon adenocarcinoma and 60 adjacent nontumor colon tissue sections were detected by immunohistochemistry. Ten paired fresh surgical human colon adenocarcinoma and adjacent nontumor colon samples were analyzed by Western blot and RT-PCR. Both Notch1 and Jagged1 were expressed in the cytoplasm of neoplastic cells of colon adenocarcinoma tissue. The protein and mRNA levels of both molecules were higher in colon adenocarcinoma than in adjacent nontumor tissue. Moreover, Notch1 was positively correlated with tumor stage. This investigation demonstrates that Notch1 and Jagged1 are up-regulated in human colon adenocarcinoma and suggests that Notch1/Jagged1 signaling might play a role in the development of colon adenocarcinoma.     

nm23-H1 expression and loss of heterozygosity in colon adenocarcinoma

BACKGROUND: The discovery that genetic alterations in oncogenes and tumour suppressor genes accompany tumour formation in many human tumours has encouraged the search for genes that promote or suppress tumour spread and metastasis; nm23 is a promising candidate for a metastasis suppressing gene.AIMS: To evaluate whether expression of nm23-H1 protein or loss of heterozygosity (LOH) of the nm23-H1 gene is associated with colon cancer progression. MATERIALS/METHODS: Paraffin wax embedded tissue sections were analysed immunohistochemically. DNA isolated from normal and tumour tissue was used for LOH analysis using a variable nucleotide tandem repeat (VNTR) marker located in the untranslated 5' region of the nm23-H1 gene. RNA isolated from tumour and normal tissue was used for "real time" RT-PCR. RESULTS: Of 102 adenocarcinomas examined, 58.8% stained weakly for nm23-H1 protein. There was a negative correlation between nm23-H1 positivity and tumour histological grade. In VNTR analysis, 70.2% of patients were informative and 27.4% of tumours had nm23-H1 LOH. There was a positive correlation between nm23-H1 LOH and both tumour histological grade and Dukes's stage. Expression of nm23-H1 mRNA was increased in 22 of 30 colon tumours compared with normal tissue. No significant correlation was found between nm23-H1 mRNA expression and histological grade or Dukes's stage of tumours. CONCLUSIONS: These findings suggest that nm23-H1 protein expression in early stages may have a role in suppressing metastasis in sporadic colon cancer, whereas at a later stage both reduced nm23-H1 protein expression and LOH of the nm23-H1 gene may play role in colon cancer progression and metastasis.     

结肠癌组织中Fas表达的定量分析

目的：探讨Fas在结肠癌中的表达及其与肿瘤发生、发展及肿瘤分化程度的关系。方法：用直接免疫荧光－流式细胞技术对50例结肠腺癌组织及手术切缘的正常结肠黏膜组织中Fas的表达进行定量检测，分析Fas表达与肿瘤大体类型、浸润深度、分化程度及淋巴结转移的关系。结果：Fas在结肠癌组织中的平均阳性率及平均荧光指数均低于其手术切缘的正常结肠黏膜组织，在12例伴有转移的结肠癌组织中Fas的平均阳性率及平均荧光指数均低于38例没有转移的结肠癌；9例肿瘤限于肌层以内的结肠癌组织中Fas平均阳性率及平均荧光指数均高于41例肿瘤侵及肌层以外的结肠癌病例。不同分化程度、不同大体类型的结肠癌组织中Fas的平均阳性率及平均荧光指数差异无显著性。结论：结肠腺癌组织中Fas的表达受到了抑制，Fas的表达与肿瘤的转移及浸润深度呈负相关，与肿瘤的分化程度及大体类型无关。     

蛋白质组学检测β-原肌球蛋白在结肠癌组织中的表达

目的：通过比较结肠腺癌与正常结肠黏膜的蛋白质组表达差异,寻找与结肠腺癌发生相关的蛋白质,筛选结肠癌诊断的分子标志物。方法: 运用蛋白质组学技术,对8例结肠腺癌组织和8例正常结肠黏膜组织进行胶内差异双向电泳（2-D）,选择差异表达超过2倍的蛋白质进行MALDI-TOF/TOF质谱分析和生物信息学分析,并对结肠癌组织中表达下调的蛋白β-原肌球蛋白(TM β)进行Western blotting验证。结果: 成功建立结肠腺癌和正常结肠黏膜的双向凝胶电泳图谱,结肠腺癌和正常黏膜组织凝胶电泳图谱中平均蛋白质斑点数分别为3 289和3 066,其中表达差异超过2倍的斑点共有31个,质谱分析和数据库检索共鉴定出18种蛋白质,包括cytokeratin 8、cytokeratin 10、S100A6、TM β、protein disulfide isomerase 等。从功能分析,这些差异蛋白与癌细胞的发生、增殖、分化、转移等相关;TM β在结肠癌组织中的表达水平Western blotting结果与电泳结果一致。结论: 蛋白质组学能有效地分离和鉴定结肠腺癌组织与正常结肠组织间的差异表达蛋白质,结肠癌组织中表达下降的TMβ,可能成为结肠癌诊断的分子标记物。     

Increased caveolin-1 expression in Alzheimer's disease brain

Increasing evidence suggests that cholesterol plays a central role in the pathophysiology of Alzheimer's disease (AD). Caveolin is a cholesterol-binding membrane protein involved in cellular cholesterol transport. We investigated the changes in the protein amount of hippocampal caveolin of autopsy-confirmed AD and aged-matched control subjects. Our results demonstrate that caveolin protein levels in the hippocampus and caveolin mRNA in the frontal cortex are up-regulated in AD by approximately two-fold, compared to control brains. These results suggest a relationship between caveolin-1 expression levels and a dysregulation of cholesterol homeostasis at the plasma membrane of brain cells. In support of this hypothesis, a significant increase in caveolin protein levels has also been observed in hippocampal tissue from ApoE-deficient (knockout) and aged wild-type mice; two situations associated with modifications of transbilayer distribution of cholesterol in brain synaptic plasma membranes. These results indicate that caveolin over-expression is linked to alterations of cholesterol distribution in the plasma membrane of brain cells and are consistent with the notion of a deterioration of cholesterol homeostasis in AD.     

窖蛋白-1在肺癌中的表达及意义

目的 探讨窖蛋白-1（caveolin-1）在不同类型肺癌组织中的表达及其与微血管密度（MVD）和临床病理因素之间的关系。方法 对154例原发性肺癌、相应癌旁正常肺组织及36例淋巴结转移癌行caveolin-1免疫组织化学染色;对154例原发性肺癌行CD34免疫组织化学（SP法）染色并进行微血管密度计数;Western印迹法检测其中50例新鲜肺癌组织及其癌旁正常肺组织中caveolin-1的表达情况。结果 caveolin-1为膜／质表达蛋白,在正常支气管上皮细胞和肺泡上皮细胞中的阳性率为100％。在肺癌组织中的阳性率为59．1％（91／154）,低于癌旁正常肺组织,P＜0．01;Western印迹结果进一步证实caveolin-1在肺鳞癌、肺腺癌组织中的表达均显著低于癌旁正常肺组织,P＜0．01。caveolin-1在小细胞肺癌（SCLC）和非小细胞肺癌（NSCLC）中的阳性率分别为7．1％和64．3％,二者间差异有统计学意义,P＜0．01。NSCLC中,有淋巴结转移组caveolin-1表达高于无淋巴结转移组（P=0．005）;Ⅲ、Ⅳ期组caveolin-1表达显著高于Ⅰ、Ⅱ期组（P=0．042）,caveolin-1表达与NSCLC的其他临床病理因素及MVD值无关（P＞0．05）。结论caveolin-1其作为一种肿瘤抑制因子的同时,可能还具有促进NSCLC进展和转移的活性。     

Caveolin-1在不同子宫内膜病变组织中的表达及意义

目的探讨小窝蛋白caveolin-1（Cav-1）在良、恶性子宫内膜组织中的表达及其临床意义。方法采用免疫组织化学S-P法和量子点免疫荧光组织化学对26例正常子宫内膜、56例增生性子宫内膜（单纯型增生30例,复杂型增生14例,不典型增生12例）和62例子宫内膜癌中Cav-1的蛋白表达进行了研究。结果Cav-1蛋白在良、恶性子宫内膜组织中平均免疫荧光强度分别为53.87±12.88,76.10±11.48,差异有显著性（P=0.001）。Cav-1在不同组别的子宫内膜中都有不同程度的阳性表达,其过表达率随着恶性程度的上升而逐渐上升的趋势,分别为53.85%、60.00%、64.29%、75.00%和80.65%。子宫内膜腺癌与正常子宫内膜、单纯性增生比较,Cav-1蛋白表达的差异均有显著性（P1=0.010,P2=0.035）,而与其它组别比较,差异均无显著性（P〉0.05）。Cav-1蛋白过表达率与子宫内膜腺癌不同的临床分期、淋巴结转移之间,差异均无显著性（P〉0.05）。结论在子宫内膜癌中,Cav-1的过表达促进了肿瘤的进展,可能起癌基因的作用。     

Up-regulated caveolin-1 accentuates the metastasis capability of lung adenocarcinoma by inducing filopodia formation

Caveolin-1, a 21- to 24-kd integral membrane protein, is primarily implicated as a tumor suppressor gene. Transformed cells normally contain reduced or no caveolin-1. Re-expression of caveolin-1 is found in advanced human and mouse prostate adenocarcinomas. To explore its potential role in tumorigenesis and tumor progression of human lung cancers, we used the well-characterized cell line (CL) series of lung adenocarcinoma cells with increasing cellular invasiveness to show that expression of caveolin-1 mRNA and protein was up-regulated with enhanced invasion/metastatic capability of CL cells. Reintroducing the caveolin-1 gene into the less invasive, caveolin-1-negative CL cells enhanced their invasive capability at least by twofold, as revealed by an in vitro chamber invasion assay. Thus, a correlation exists for both constitutive and induced expression of caveolin-1 in CL cells. Immunohistochemical examination of caveolin-1 was performed in 95 specimens obtained retrospectively from patients who had lung adenocarcinoma either with (35 patients) or without (60 patients) ipsilateral hilar/peribronchial tumor-metastasized lymph nodes. Caveolin-1 immunoreactivity was either totally absent or just barely detectable in a few lung adenocarcinoma cells from cases diagnosed as lung adenocarcinoma without regional lymph node metastasis. In contrast, increased caveolin-1 immunoreactivity both in number and intensity was detected in primary lung adenocarcinoma cells as well as in cancer cells that metastasized to regional lymph nodes from the cases diagnosed as advanced lung adenocarcinoma with nodal metastases. Multivariate analysis considering caveolin-1 immunoreactivity in addition to the established prognostic parameters such as pT stage, pN in these patients confirmed that caveolin-1 is an independent functional predictor of poor survival. We further revealed that up-regulated caveolin-1 in CL cells is necessary for mediating filopodia formation, which may enhance the invasive ability of lung adenocarcinoma cells.     

Correlation of clinicopathological features and LGR5 expression in colon adenocarcinoma

Colon cancer stem cells (CSCs) are closely related to tumorigenesis and treatment response, and LGR5 is currently the most robust and reliable CSC marker in colorectal cancer (CRC). However, LGR5 expression in CRC tumor budding (TB) is not well understood. We examined the clinicopathological and prognostic significance of LGR5 in CRC TB. LGR5 expression was evaluated by RNAscope, a newly developed RNA in situ hybridization technique, using a tissue microarray consisting of 55 patient samples of TB in colon adenocarcinoma (CA) selected from the medical archives at our hospital. Patients were stratified into negative and positive LGR5 expression groups. Tumor-infiltrating lymphocytes (TILs) and histological grade were lower in the LGR5-positive group compared with the LGR5-negative group (P = .0407 and P = .0436, respectively). There was no significant difference in overall survival between the LGR5-positive group and the LGR5-negative group (log-rank test, P = .6931). LGR5 expression did not remain a predictor of prognosis in univariate analysis (OR = 0.84, 95% CI: 0.33–2.02, P = .6928). LGR5 expression may be affected by TILs, which have been demonstrated to be associated with worse prognosis in the budding area of CA and is an important potential marker of prognosis.     

Coordinated expression of galectin-3 and caveolin-1 in thyroid cancer

Galectin-3 (Gal3) is the single most accurate marker for the diagnosis of differentiated thyroid cancer (DTC). Gal3 overrides the tumour suppressor activity of caveolin-1 (Cav1) and functions in concert with Cav1 to promote focal adhesion turnover and tumour cell migration and invasion. To study their coordinated role in progression of a human cancer, we investigated the expression of Gal3 and Cav1 in specimens of human benign thyroid lesions, DTC and anaplastic thyroid cancer (ATC). Gal3 and Cav1 expression is significantly associated with DTC and ATC, but not benign nodules. Essentially all Cav1-positive DTC cancers express Gal3, supporting the synergistic activity of these two proteins in DTC progression. Similarly, coordinated elevated Gal3/Cav1 expression was observed in three DTC-derived cell lines (papillary TCP1 and KTC1 and follicular FTC133) but only one (ACT1) of five ATC-derived cell lines. Using siRNA knockdown, Gal3 and Cav1 were shown to be required for RhoA GTPase activation, stabilization of focal adhesion kinase (FAK; a measure of focal adhesion signalling and turnover) and increased migration of the DTC cell lines studied, but not the ATC cell lines, including ACT1, which expresses elevated levels of Gal3 and Cav1. Co-expression of Gal3 and Cav1 in the T238 anaplastic cell line stabilized FAK-GFP in focal adhesions. Gal3 and Cav1 therefore function synergistically to promote focal adhesion signalling, migration and progression of DTC.     

Invasive papillary adenocarcinoma of the colon

Colonic adenocarcinomas are among the most common type of tumors. In this report, we present the morphologic, immunohistochemical, and microsatellite findings of 2 cases with a distinct invasive papillary component. Both tumors arose from polyps in middle-aged patients, followed an aggressive course, and showed a superficial adenomatous component. The immunohistochemical stains showed that the tumor cells were negative for p27 and p53; both tumors were microsatellite stable, that is, with no microsatellite instability in the 6 markers studied, and there was no loss of the mismatch repair proteins hMSH2 or hMLH1. These findings suggest that these tumors follow the tumor-suppressor pathway and represent an aggressive subtype of colonic adenocarcinoma.     

Reduced FHIT expression is associated with tumor progression in sporadic colon adenocarcinoma

Purpose

Tumor supressor gene FHIT was identified at chromosome 3p14.2 spanning the FRA3B fragile site and is very often inactivated in different types of cancer. The aim of this study was to examine the frequency of FHIT gene LOH as well as FHIT mRNA and protein expression in sporadic colon adenocarcinoma.

Methods

The results of LOH, real-time qRT-PCR and imunohistochemical analyses were correlated with clinico-pathological characteristics of patients and their tumors in order to evaluate the role of FHIT gene/protein in sporadic colon adenocarcinoma tumorigenesis.

Results

One hundred and thirty one (96.3%) samples were informative for both markers and 33/131 (25.2%) demonstrated LOH. Expression of FHIT mRNA was significantly decreased in colon tumors relative to that in corresponding normal tissue (p = 7.2 × 10^− 6). Most of the samples (54.0%) were negative for FHIT protein, 26.4% adenocarcinomas showed a weak to moderate immunostaining and 19.6% adenocarcinomas showed strong FHIT immunostaining. No correlation was found between FHIT gene LOH status, mRNA expression or FHIT protein immunostaining and clinico-pathological characteristics. Expression of FHIT mRNA was significantly decreased in FHIT LOH positive tumors (p = 0.027). Patients with LOH negative tumors or FHIT protein positive tumors had longer survival but this findings were not statistically significant.

Conclusions

Our overall results suggest that reduced expression of FHIT gene may be associated with the progression of these malignant tumors.     

低氧诱导的小窝蛋白-1上调参与人肺腺癌细胞A549迁移和侵袭

 目的:探讨低氧诱导剂二氯化钴（CoCl2）对小窝蛋白-1（Cav-1）生成的调节作用及后者对人肺腺癌A549细胞迁移、侵袭的影响。方法:检测肺癌患者伴恶性胸水（MPE）和结核性胸膜炎患者胸水（TBPE）中Cav-1和缺氧诱导因子(HIF)-1α浓度,比较两者相关性;以CoCl2和（或）HIF-1α抑制剂YC-1作用于A549细胞ELISA法检测细胞上清Cav-1和HIF-1α浓度;分别采用细胞划痕实验及Transwell小室侵袭实验研究CoCl2刺激表达的Cav-1对A549细胞迁移和侵袭的影响。结果:MPE中Cav-1和HIF-1α浓度明显高于TBPE,两组患者胸水中Cav-1与HIF-1α均呈正相关。CoCl2浓度和时间依赖性诱导A549细胞Cav-1和HIF-1α生成,200 μmol/L或24 h达到峰值;浓度>200 μmol/L或作用时间超过24 h则呈现浓度或时间依赖性抑制。HIF-1α抑制剂YC-1浓度依赖性抑制HIF-1α和Cav-1生成。CoCl2浓度依赖性增强A549细胞迁移和侵袭,200 μmol/L作用最强;YC-1对上述过程产生抑制效应。结论: 肺癌患者胸腔积液中Cav-1浓度升高,低氧诱导Cav-1生成的变化可能参与了A549细胞迁移和侵袭,HIF-1α可能对Cav-1生成发挥影响。     

Metastatic potential of human CX-1 colon adenocarcinoma cells is dependent on the expression of sialosyl Le a antigen

Several lines of evidence indicate that sialosyl Le a , tumor-associated carbohydrate antigen present on human colon carcinoma cells, is involved in formation of metastases. To study the role of this carbohydrate structure in development of metastases, we have used the clone of human colon carcinoma CX-1 cells transfected with antisense expression vector containing fragment of cDNA for a1,3/4-fucosyltransferase (FT III), which is involved in synthesis of sialosyl Le a tetrasaccharide. It has been reported previously that, in contrast to the parental cells, the antisense-transfected CX-1.1AS5 cells do not express sialosyl Le a and do not adhere to E-selectin-expressing CHO cells. In the present work we have studied the formation of liver metastases by CX-1.1AS5 cells after their orthotopic or intrasplenic implantation into athymic nu/nu mice. After orthotopic implantation of sialosyl Le a -negative colon carcinoma CX-1.1AS5 cells, the number of mice with liver metas-tases was markedly lower (21% of mice) in comparison with their number after implantation of the parental CX-1.1 cells (86% of mice). However, no differences in ability to form colonies in liver were observed between parental CX-1.1 cells and antisense-transfected CX-1.1AS5 cells after intrasplenic inoculation. The liver metastases were formed in 89% and 84% of mice, respectively. Our data support the thesis on the importance of sialosyl Le a antigen expression in the development of liver metastases by colon cancer cells, and indicate the role of transplantation route and primary tumor localization in formation of metastases.© Kluwer Academic Publishers 1998     

Elevated E-cadherin and alpha/beta-catenin expression after androgen deprivation therapy in prostate adenocarcinoma

The histological patterns of anti-androgen-treated prostate adenocarcinoma mimic high grade tumors classified according to the widely used Gleason scoring system. However, the biological characteristics of anti-androgen treated carcinoma are largely unknown. E-cadherin, alpha-catenin, and beta-catenin adhesion molecules are down-regulated in pharmacologically untreated high grade prostate carcinoma. In this study, we used immunohistochemical techniques to investigate their expression in twenty acinar adenocarcinomas after anti-androgen therapy in prostatectomy specimens. After adrogen ablation therapy, expression of all these adhesion molecules was higher than that of pretreatment biopsies of the same patient group and high grade matched untreated controls. These results emphasize the inaccuracy of the Gleason score for anti-androgen-treated prostate adenocarcinoma and the more differentiated phenotype of prostate adenocarcinoma after anti-hormonal therapy.     

Caveolin-1在高盐饮食损伤糖尿病大鼠血管中的作用

目的:观察1型糖尿病(DM)大鼠给予高盐饮食后内皮细胞功能障碍的可能机制。方法:SD大鼠(150~180 g)60只,腹腔注射链唑霉素(70 mg/kg),3 d后空腹血糖≥16.7 mmol/L为1型DM大鼠。正常大鼠和DM大鼠分别给予正常饮食和高盐饮食(8%Na Cl)6周。检测肠系膜动脉舒张功能,Western blot技术检测血管中Akt、内皮型一氧化氮合酶(e NOS)、caveolin-1(Cav-1)等蛋白的水平。结果:高盐饮食DM大鼠收缩压显著高于DM组,其肠系膜动脉乙酰胆碱和胰岛素的舒张作用显著下降(P0.01)。Akt、p-e NOS和NO水平均显著低于DM组(P0.01),Cav-1显著增高(P0.01)。结论:1型糖尿病大鼠高盐饮食血管功能障碍可能与抑制内皮细胞Akt激活及增强Cav-1表达导致的e NOS活性下降有关。