环氧合酶-2、前列腺素E2在大肠腺瘤和腺癌组织中的表达

目的:研究COX-2、PGE2在大肠腺瘤和腺癌组织中的表达和意义。方法:选取组织标本118例,其中正常大肠黏膜30例,大肠腺瘤43例,大肠腺癌组织45例。Real Time PCR法检测组织中COX-2mRNA的表达,免疫组织化Elivision法检测组织中COX-2的蛋白表达,放射免疫法测定组织中PGE2含量。结果:COX-2在大肠腺癌组织中的mRNA的表达、阳性表达率及光密度值分别高于大肠腺瘤及正常黏膜组(P<0.05);且大肠腺瘤组高于正常黏膜组(P<0.05)。大肠腺癌组织PGE2含量高于大肠腺瘤及正常大肠黏膜(P<0.01);且大肠腺瘤高于正常大肠黏膜(P<0.01)。结论:大肠黏膜癌变过程中COX-2表达增高,PGE2合成增多。     

Regulation of the apoptosis-inducing kinase DRAK2 by cyclooxygenase-2 in colorectal cancer

Background:

Cyclooxygenase-2 (COX-2) is over-expressed in colorectal cancer (CRC), rendering tumour cells resistant to apoptosis. Selective COX-2 inhibition is effective in CRC prevention, although having adverse cardiovascular effects, thus focus has shifted to downstream pathways.

Methods:

Microarray experiments identified genes regulated by COX-2 in HCA7 CRC cells. In vitro and in vivo regulation of DRAK2 (DAP kinase-related apoptosis-inducing kinase 2 or STK17β, an apoptosis-inducing kinase) by COX-2 was validated by qRT-PCR.

Results:

Inhibition of COX-2 induced apoptosis and enhanced DRAK2 expression in HCA7 cells (4.4-fold increase at 4 h by qRT-PCR, P=0.001), an effect prevented by co-administration of PGE₂. DRAK2 levels were suppressed in a panel of human colorectal tumours (n=10) compared to normal mucosa, and showed inverse correlation with COX-2 expression (R=−0.68, R²=0.46, P=0.03). Administration of the selective COX-2 inhibitor rofecoxib to patients with CRC (n=5) induced DRAK2 expression in tumours (2.5-fold increase, P=0.01). In vitro silencing of DRAK2 by RNAi enhanced CRC cell survival following COX-2 inhibitor treatment.

Conclusion:

DRAK2 is a serine–threonine kinase implicated in the regulation of apoptosis and is negatively regulated by COX-2 in vitro and in vivo, suggesting a novel mechanism for the effect of COX-2 on cancer cell survival.     

选择性环氧合酶-2 抑制剂 NS-398 抑制多药耐药细胞株 P-糖蛋白表达

目的:探讨选择性环氧合酶-2(cyclooxygenase-2,COX-2)抑制剂NS-398对多药耐药细胞株K562/ADM细胞P-糖蛋白(P-glycoprotein,P-gp)表达的影响。方法:K562/ADM细胞经浓度分别为10μmol/L、20μmol/L、40μmol/L、80μmol/L、160μmol/L的NS-398处理,24h、48h、72h后用RT-PCR法检测MDR1mRNA的表达、用流式细胞仪检测mdr1蛋白表达。结果:随着NS-398浓度的升高以及作用时间延长,MDR1mRNA、p-gp表达降低,不同浓度的药物与测量时间之间存在着交互作用(P<0.05)。结论:选择性环氧合酶-2抑制剂NS-398可抑制K562/ADM细胞的MDR1/P-gp表达。     

非类固醇类抗炎药NS398对肺癌H460细胞MT1-MMP表达的影响

目的:探讨非类固醇类抗炎药NS398对肺癌H460细胞增殖及其膜型基质金属蛋白酶-1(mem-brane type 1-matrix metalloproteinase,MT1-MMP)表达的影响。方法:应用MTT法检测细胞生长抑制率,免疫荧光法检测MT1-MMP蛋白质表达,酶联免疫吸附法(enzyme-linked immunosorbentassay,ELISA)检测细胞培养液中活性基质金属蛋白酶-2(matrixmetalloproteinase-2,MMP-2)的浓度。结果:NS398可抑制H460细胞的增殖及MT1-MMP蛋白质的表达,减少H460细胞培养液中活性型MMP-2的含量,并呈剂量依赖关系。结论:NS398可能通过抑制肺癌细胞MT1-MMP表达及MMP-2的激活而抑制肺癌细胞的侵袭转移。     

非类固醇类抗炎药NS398对肺癌H460细胞MT1-MMP表达的影响

目的：探讨非类固醇类抗炎药NS398对肺癌H460细胞增殖及其膜型基质金属蛋白酶-1（membrane type 1-matrix metalloproteinase,MT1-MMP）表达的影响。方法：应用MTT法检测细胞生长抑制率,免疫荧光法检测MT1-MMP蛋白质表达,酶联免疫吸附法（enzyme—linked immunosorbentassay,ELISA）检测细胞培养液中活性基质金属蛋白酶-2（matrix metalloproteinase-2,MMP-2）的浓度。结果：NS398可抑制H460细胞的增殖及MT1-MMP蛋白质的表达,减少H460细胞培养液中活性型MMP-2的含量,并呈剂量依赖关系。结论：NS398可能通过抑制肺癌细胞MT1-MMP表达及MMP-2的激活而抑制肺癌细胞的侵袭转移。     

Correlations between cyclooxygenase-2 expression and angiogenic factors in primary tumors and liver metastases in colorectal cancer

BACKGROUND: Angiogenesis is required for growth and metastasis of colorectal cancer (CRC), and several positive regulators of tumor angiogenesis have been identified. Cyclooxygenase-2 (COX-2), known to be elevated in several human cancers, regulates angiogenesis by inducing angiogenic factors. The aim of this study was to clarify the levels and evaluate the relationships of COX-2, vascular endothelial growth factor A and C, thymidine phosphorylase (TP) and microvascular density (MVD) in paired tissue specimens between primary CRC and corresponding metastatic liver cancer. METHODS: Tissue samples from pairs of primary tumors and corresponding metastatic liver tumors from 44 patients with CRC were immunohistochemically evaluated for COX-2, VEGF-A, VEGF-C, TP and MVD. RESULTS: The primary and corresponding metastatic liver tumors tended to show concordant immunoreactivity for COX-2 (P = 0.005, rs = 0.428), VEGF-A (P = 0.039, rs = 0.314), TP (P = 0.005, rs = 0.422) and MVD (P = 0.046, rs = 0.304) by Spearman rank test. The rate of COX-2 immunoreactivity was higher in liver metastases than in primary tumors (P = 0.002), while the rate of VEGF-A was higher in primary tumors than in liver metastases (P = 0.0004). The incidence of TP immunoreactivity and the level of MVD did not differ between primary and metastatic liver tumors (P = 0.247; P = 0.229). Significant correlations were found between COX-2 immunoreactivity and VEGF-A immunoreactivity in metastatic liver tumors (P = 0.033) as well as in primary tumors (P = 0.008). CONCLUSION: The positive correlations between COX-2, VEGF-A, TP and MVD in primary CRC and liver metastasis as demonstrated here will help to predict the angiogenic activity of liver metastasis by analyzing primary tumors, allowing for individualized cancer treatment options.     

Role of cyclooxygenase-2 in colorectal cancer

Cyclooxygenase-2 (COX-2) is an inducible enzyme that regulates prostaglandin synthesis and is overexpressed at sites of inflammation and in several epithelial cancers. Recently, a causal link for COX-2 in epithelial tumorigenesis was shown in genetically-manipulated animal models of colon and breast carcinoma. Data indicate that COX-2 is involved in the regulation of apoptosis, angiogenesis, and tumor cell invasiveness, which appear to contribute to its effects on tumorigenesis. Multiple studies have shown that nonselective COX and selective COX-2 inhibitors effectively prevent experimental colon cancer. Furthermore, sulindac and the selective COX-2 inhibitor celecoxib were shown to regress colorectal polyps in patients with familial adenomatous polyposis. Although the exact anti-tumor mechanisms of these agents await further study, data indicate that both COX-dependent and COX-independent mechanisms may be important. In this review, the association between COX-2 and colorectal tumorigenesis and potential mechanisms of this effect are discussed. Additionally, evidence supporting the role of NSAIDs and selective COX-2 inhibitors for the prevention and treatment of human colorectal cancer is reviewed.     

NS-398对人卵巢癌C13K细胞株增殖的抑制作用及对Snail和E-cadherin表达的调节

目的:探讨选择性环氧合酶-2(cyclooxygenase-2,COX-2)抑制剂NS-398对卵巢癌C13K细胞株的增殖抑制作用以及对Snail和E-cadherin基因表达的影响.方法:体外培养卵巢癌C13K细胞,不同浓度的NS-398(50μmol/L、100μmol/L、200μmol/L)作用于C13K细胞48h、72h后,MTT法分析不同浓度NS-398对细胞增殖的影响;RT-PCR法检测胞内Snail mRNA、E-cadherin mRNA的表达水平;免疫组化SABC法检测Snail、E-cadherin蛋白的表达.结果:NS-398对卵巢癌C13K细胞株增殖的抑制作用呈现时间和浓度依赖性,与对照组相比有统计学差异(P<0.05).Snail mRNA和蛋白的表达随NS-398浓度的升高和作用时间的延长,逐渐降低;而E-cadherin mRNA 和蛋白的表达则逐渐升高,与对照组相比有统计学差异(P<0.05).结论:选择性COX-2抑制剂NS-398可明显抑制C13K细胞株的增殖,其机制可能与Snail和E-cadherin mRNA表达有关,为卵巢癌的治疗提供了新的靶点和理论依据.     

环氧合酶-2选择性抑制剂NS-398诱导人肝癌BEL-7402细胞凋亡及其机制探讨

目的:探讨环氧合酶-2(cyclooxygenase-2,COX-2)选择性抑制剂NS-398对人肝癌BEL-7402细胞凋亡及凋亡抑制蛋白survivin、XIAP和c-IAP1表达的调节作用.方法:用不同浓度的NS-398作用BEL-7402细胞后,MTT法测定细胞增殖抑制情况,FCM法和TUNEL法检测细胞凋亡情况,免疫细胞化学法检测COX-2、survivin、XIAP和c-IAP1蛋白的表达情况.结果:NS-398 可以显著抑制BEL-7402细胞的增殖,诱导其凋亡.免疫细胞化学法检测结果显示,与未处理组相比,NS-398作用可使BEL-7402细胞中COX-2、survivin、XIAP和c-IAP1蛋白的表达明显下调(P<0.01).结论:NS-398对人肝癌细胞株BEL-7402有抑制细胞增殖和诱导细胞凋亡的作用,其机制可能与通过下调survivin、XIAP和c-IAP1的表达有关.     

NS-398对人胃癌细胞系SGC-7901增殖、凋亡和COX-2表达的影响

目的 探讨环氧合酶-2(COX-2)抑制剂NS-398对人胃癌细胞系SGC-7901增殖、凋亡及COX-2表达的影响,并进一步探讨其作用的可能机制.方法 采用四甲基偶氮唑蓝(MTT)法检测NS-398对SGC -7901细胞的杀伤抑制作用;免疫细胞化学法检测SGC-7901细胞内COX-2的蛋白表达情况;ELISA法检测NS-398作用于SGC-7901细胞后PGE2释放水平;流式细胞仪检测SGC-7901细胞的凋亡情况.结果 NS-398对胃癌SGC-7901细胞具有较强的抑制作用,且这种抑制作用随浓度和时间的增加而增强,呈剂量-时间双效应关系(P＜0.05);不同浓度NS-398作用下的SGC-7901细胞中,COX-2的表达明显减弱,且呈剂量梯度下降(P＜ 0.05);NS-398可抑制PGE2释放,并且这种抑制作用呈剂量效应关系,与对照组相比差异有统计学意义(P＜ 0.05);NS-398作用于SGC-7901细胞48 h后,细胞凋亡率升高,且呈剂量效应(P＜0.05).结论 NS-398通过COX-2依赖途径抑制SGC-7901细胞增殖并促进其凋亡.     

CRC-113 gene expression signature for predicting prognosis in patients with colorectal cancer

Colorectal cancer (CRC) is the third leading cause of global cancer mortality. Recent studies have proposed several gene signatures to predict CRC prognosis, but none of those have proven reliable for predicting prognosis in clinical practice yet due to poor reproducibility and molecular heterogeneity. Here, we have established a prognostic signature of 113 probe sets (CRC-113) that include potential biomarkers and reflect the biological and clinical characteristics. Robustness and accuracy were significantly validated in external data sets from 19 centers in five countries. In multivariate analysis, CRC-113 gene signature showed a stronger prognostic value for survival and disease recurrence in CRC patients than current clinicopathological risk factors and molecular alterations. We also demonstrated that the CRC-113 gene signature reflected both genetic and epigenetic molecular heterogeneity in CRC patients. Furthermore, incorporation of the CRC-113 gene signature into a clinical context and molecular markers further refined the selection of the CRC patients who might benefit from postoperative chemotherapy. Conclusively, CRC-113 gene signature provides new possibilities for improving prognostic models and personalized therapeutic strategies.     

The bone morphogenetic protein pathway is active in human colon adenomas and inactivated in colorectal cancer

BACKGROUND: Transforming growth factor beta (TGFbeta) is important in colorectal cancer (CRC) progression. Bone morphogenetic proteins (BMPs), a subgroup within the TGFbeta superfamily, recently also have been implicated in CRC, but their precise role in CRC has yet to be investigated. METHODS: The authors used a tissue microarray and immunohistochemistry of BMP receptors and signal transduction elements in adenomas and CRC specimens to elucidate the role of BMP signaling in CRC carcinogenesis. RESULTS: The adenoma specimens expressed all 3 BMP receptors (BMPRs) (BMPR type 1a [BMPR1a], BMPR1b, and BMPR2) and expressed SMAD family member 4 (SMAD4); and 20 of 22 adenomas (90.9%) exhibited active BMP signaling, as determined by nuclear phosphorylated SMAD1,5,8 (pSMAD1,5,8) expression. In contrast, pSMAD1,5,8 nuclear staining was present in 5 CRC specimens (22.7%) but was lost in 17 CRC specimens (77.3%; cancer vs adenoma; P< .0001). The earliest loss of pSMAD1,5,8 nuclear staining was detected in regions of high-grade dysplasia/carcinoma in situ within adenomas. CRCs showed frequent loss of BMPR2 (P< .0001) and SMAD4 (P< .01) compared with adenomas. Negative expression of BMPR2 was observed more frequently in earlier stage cancers (Dukes stage B) than in advanced cancers (Dukes stage C; P< .05). CONCLUSIONS: Taken together, the current results indicated that loss of BMP signaling correlates tightly with progression of adenomas to cancer and occurs relatively early during cancer progression.     

Induction of apoptosis by cyclo-oxygenase-2 inhibitor NS398 through a cytochrome C-dependent pathway in esophageal cancer cells.

Non-steroidal anti-inflammatory drugs (NSAIDs) can induce tumor cells to undergo apoptosis in vitro. They have also shown cancer-preventive activity in vivo. The mechanism of their effects is, however, not well defined. We investigated the mechanism by which a new NSAID, NS398, induces apoptosis in esophageal cancer cell lines. NS398 decreased cell viability in 2 cyclo-oxygenase-2-positive (COX-2(+)) esophageal cancer cell lines but not in a COX-2(-) cell line. DNA fragmentation and TUNEL assays demonstrated that NS398 induced the 2 COX-2(+) cancer cell lines to undergo apoptosis. The percentage of apoptosis induced by NS398 was associated with the level of COX-2 expression. Further investigation showed that the cytochrome c pathway was responsible for NS398-induced apoptosis; i.e., cytochrome c was released from mitochondria, caspase-9 and caspase-3 were activated and finally poly(ADP-ribose)polymerase (PARP) was cleaved. Furthermore, the effect of NS398 was inhibited by the caspase inhibitor Z-DEVD-FMK and prostaglandin E(2). In contrast, bcl-2, bax, c-myc, Fas and Fas-ligand showed minor changes. Altogether, our data suggest that induction of apoptosis by NS398 is associated with COX-2 expression and occurs through the cytochrome c-dependent pathway, which sequentially activates caspase-9 and caspase-3 and cleaves PARP.     

早期大肠癌中环氧化酶-2的表达及其临床意义

目的　研究早期大肠癌中COX 2的表达及其临床意义。方法　使用免疫组化染色法分别检测了 32例早期大肠癌外科术后石蜡标本、33例大肠腺瘤、18例正常大肠粘膜活检组织中COX 1和COX 2蛋白的表达。结果　依表达程度由 ( )至 (+++)四级计算 ,COX 2的表达率在正常结肠粘膜中分别为 83.3%、16 .7%、0 %、0 % ;在结肠腺瘤中分别为 12 .1%、4 2 .4 %、36 .4 %、9.1% ;早期大肠癌中分别为 6 .3%、2 8.1%、4 6 .9%、18.7%。早期大肠癌、大肠腺瘤中COX 2的表达率均明显高于正常粘膜 (P <0 .0 1) ,但早期大肠癌与大肠腺瘤中COX 2的表达率无显著性差异。COX 2的表达与早期大肠癌、大肠腺瘤各项被研究的临床病理特征无关。COX 1在早期大肠癌 ,大肠腺瘤及正常肠粘膜中呈低水平表达。结论　COX 2的表达在由正常大肠粘膜至大肠腺瘤、早期癌的发展过程中呈上调趋势。COX 2的表达是大肠肿瘤形成过程中的早期事件 ,不能作为大肠癌早期诊断的癌标记物。     

Analysis of differential gene expression in colorectal cancer and stroma using fluorescence-activated cell sorting purification

Tumour stroma gene expression in biopsy specimens may obscure the expression of tumour parenchyma, hampering the predictive power of microarrays. We aimed to assess the utility of fluorescence-activated cell sorting (FACS) for generating cell populations for gene expression analysis and to compare the gene expression of FACS-purified tumour parenchyma to that of whole tumour biopsies. Single cell suspensions were generated from colorectal tumour biopsies and tumour parenchyma was separated using FACS. Fluorescence-activated cell sorting allowed reliable estimation and purification of cell populations, generating parenchymal purity above 90%. RNA from FACS-purified and corresponding whole tumour biopsies was hybridised to Affymetrix oligonucleotide microarrays. Whole tumour and parenchymal samples demonstrated differential gene expression, with 289 genes significantly overexpressed in the whole tumour, many of which were consistent with stromal gene expression (e.g., COL6A3, COL1A2, POSTN, TIMP2). Genes characteristic of colorectal carcinoma were overexpressed in the FACS-purified cells (e.g., HOX2D and RHOB). We found FACS to be a robust method for generating samples for gene expression analysis, allowing simultaneous assessment of parenchymal and stromal compartments. Gross stromal contamination may affect the interpretation of cancer gene expression microarray experiments, with implications for hypotheses generation and the stability of expression signatures used for predicting clinical outcomes.     

选择性 COX -2 抑制剂治疗胃癌的研究现状与展望简

环氧化酶-2催化花生四烯酸生成前列腺素的反应,在组织中呈诱导性表达,与肿瘤、炎症及疼痛等病理过程密切相关。选择性COX-2抑制剂塞来昔布可降低肿瘤组织E-钙黏素表达,降低癌细胞的侵}袭性,减少癌细胞的浸润与转移。塞来昔布治疗胃癌的临床前研究取得了丰硕的成果,本文将讨论近年来该领域的一些重要进展。     

Expression differences of serum prealbumin in benign and malignant colorectal tumors

Objective： The aim of the study was to investigate the expression differences of serum prealbumin in patients with benign and malignant colorectal tumors and its clinical significance. Methods： The concentrations of total protein, albumin, prealbumin, hemoglobin of 113 colorectal cancer patients （cancer group） and 87 colorectal adenomas （adenoma group） were tested in Yixing Hospital Affiliated to Jiangsu University （China） during August 2013 to December 2013. Then the differences between the two groups were compared. Results： In colorectal cancer patients, the concentrations of serum prealbumin in 39/113 cases, total protein in 16/113 cases, albumin in 38/113, hemoglobin in 32/113 were lower than normal ranges. While, in colorectal adenoma patients, the concentrations of serum prealbumin in 4/87 cases, total protein in 2/87, albumin in 1/87, hemoglobin in 2/87 were below the detection limit. Comparative analysis showed that, average expression levels of serum prealbumin, albumin, total protein, hemoglobin in colorectal cancer patients were lower than those of colorectal adenoma patients, the difference was statistically significant （P 〈 0.05）, and colorectal cancer patients were more likely to have lower levels of above indicators （P 〈 0.05）. Conclusion： Compared to colorectal adenoma patients, patients with colorectal cancer have lower average expression levels, and were easier to have lower expression levels of serum albumin, albumin, total protein and hemoglobin, which suggest that colorectal cancer patients are more likely to have metabolic change, and clinic notable.     

SOX2在结直肠癌表达的临床观察

目的：观察SOX2在结直肠癌组织的表达情况,探讨SOX2在结直肠癌中表达的临床意义。方法收集103例有60～125个月（中位随访时间84个月）随访资料的结直肠癌及其相应的正常结直肠黏膜标本,应用免疫组化方法检测SOX2的表达,分析SOX2表达与临床特征的关系。结果结直肠癌组织中SOX2蛋白的表达率显著高于癌旁正常肠黏膜（P＜0.001）;SOX2表达与结直肠癌分化程度显著负相关（P＜0.01）,与结直肠癌TNM分期、淋巴结转移个数及远处转移程度正相关（P＜0.05）。SOX2表达与结直肠癌患者术后5年生存率和3年无瘤生存率也具有相关性（P＜0.05）。结论 SOX2蛋白异常表达可作为提示结直肠癌预后判断的重要参考指标。