Aurora-A高表达对食管癌细胞侵袭和 MMP-9表达的影响

目的:建立Aurora-A高表达的稳定细胞系,并探讨Aurora-A高表达对食管癌细胞侵袭和MMP-9蛋白表达与活性的影响。方法:利用脂质体法稳定转染Aurora-A表达质粒,通过Westernblot和RT-PCR鉴定Aurora-A高表达的稳定细胞系。利用细胞体外侵袭实验观察细胞的侵袭能力,并通过Western blot、ELISA和明胶酶谱的方法观察MMP-9的蛋白表达水平和活性。结果:建立了Aurora-A高表达的稳定细胞系,且Aurora-A高表达能增加食管癌细胞的体外侵袭能力,并提高了MMP-9的蛋白表达水平和活性。结论:初步阐明了Aurora-A促进食管癌细胞侵袭的作用以及分子机制,为Aurora-A可能成为治疗食管癌的有效靶点提供了依据。     

P2X7 Mediates ATP-Driven Invasiveness in Prostate Cancer Cells

The ATP-gated P2X7 has been shown to play an important role in invasiveness and metastasis of some tumors. However, the possible links and underlying mechanisms between P2X7 and prostate cancer have not been elucidated. Here, we demonstrated that P2X7 was highly expressed in some prostate cancer cells. Down-regulation of P2X7 by siRNA significantly attenuated ATP- or BzATP-driven migration and invasion of prostate cancer cells in vitro, and inhibited tumor invasiveness and metastases in nude mice. In addition, silencing of P2X7 remarkably attenuated ATP- or BzATP- driven expression changes of EMT/invasion-related genes Snail, E-cadherin, Claudin-1, IL-8 and MMP-3, and weakened the phosphorylation of PI3K/AKT and ERK1/2 in vitro. Similar effects were observed in nude mice. These data indicate that P2X7 stimulates cell invasion and metastasis in prostate cancer cells via some EMT/invasion-related genes, as well as PI3K/AKT and ERK1/2 signaling pathways. P2X7 could be a promising therapeutic target for prostate cancer.     

Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells

Mechanisms of the progression from Barrett’s esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK) inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H₂O₂ production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H₂O₂ production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H₂O₂ production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA.     

Cost-Effectiveness of Cetuximab for Advanced Esophageal Squamous Cell Carcinoma

BackgroundCostly biologicals in palliative oncology are emerging at a rapid pace. For example, in patients with advanced esophageal squamous cell carcinoma addition of cetuximab to a palliative chemotherapy regimen appears to improve survival. However, it simultaneously results in higher costs. We aimed to determine the incremental cost-effectiveness ratio of adding cetuximab to first-line chemotherapeutic treatment of patients with advanced esophageal squamous cell carcinoma, based on data from a randomized controlled phase II trial.MethodsA cost effectiveness analysis model was applied based on individual patient data. It included only direct medical costs from the health-care perspective. Quality-adjusted life-years and incremental cost-effectiveness ratios were calculated. Sensitivity analysis was performed by a Monte Carlo analysis.ResultsAdding cetuximab to a cisplatin-5-fluorouracil first-line regimen for advanced esophageal squamous cell carcinoma resulted in an the incremental cost-effectiveness ratio of €252,203 per quality-adjusted life-year. Sensitivity analysis shows that there is a chance of less than 0.001 that the incremental cost-effectiveness ratio will be less than a maximum willingness to pay threshold of €40,000 per quality-adjusted life-year, which is representative for the threshold used in The Netherlands and other developed countries.ConclusionsAddition of cetuximab to a cisplatin-5-fluorouracil first-line regimen for advanced esophageal squamous cell carcinoma is not cost-effective when appraised according to currently accepted criteria. Cost-effectiveness analyses using outcome data from early clinical trials (i.c. a phase II trial) enable pharmaceutical companies and policy makers to gain early insight into whether a new drug meets the current eligibility standards for reimbursement and thereby potential admittance for use in regular clinical practice.     

紫铆因对食管鳞癌细胞增殖和存活影响的初步研究

研究紫铆因对人食管鳞癌细胞增殖和存活的影响。通过MTS和软琼脂集落实验检测紫铆因对食管鳞癌增殖的抑制,生化分析仪检测紫铆因对食管鳞癌糖酵解的影响,并利用免疫印迹检测紫铆因对食管鳞癌细胞增殖和凋亡激活相关蛋白分子的表达。结果发现紫铆因剂量依赖性抑制KYSE150和Eca109细胞增殖,下调EGFR信号通路活化,抑制HK2的表达及糖酵解。一定浓度的紫铆因能诱导食管鳞癌细胞发生凋亡,caspase3和PARP被剪切,Bcl-2和Mcl-1表达下调,但Bcl-XL未见明显改变。结果证明紫铆因抑制食管鳞癌的增殖,可能与EGFR信号通路和糖酵解被抑制,及促存活蛋白Bcl-2和Mcl-1的表达下调有关。     

H2-Calponin 在食管鳞癌中的表达及其与食管磷癌预后的关系

目的:探讨H_2-Calponin在食管磷癌组织中的表达及其与食管磷癌患者临床病理特征及预后的相关性。方法:利用免疫组织化学染色技术检测73例食管磷癌及相应癌旁组织中H_2-Calponin的表达情况,并分析其与食管磷癌患者临床病理参数及预后的关系。结果:H_2-calponin在食管磷癌组织中的阳性表达率为95.8%(70/73),显著高于癌旁组织(35.8%,24/67),差异具有统计学意义(p0.0001)。H_2-calponin的表达与食管癌患者的性别、年龄、肿瘤大小、浸润深度及淋巴结转移均无显著相关性,但与AJCC分期显著相关(P0.05)。H_2-calponin的表达水平影响食管癌患者预后及生存期。结论:H_2-Calponin在食管磷癌组织中呈高表达并可预示食管磷癌预后不良。     

食管鳞癌与腺癌差异基因表达的对比分析

目的:研究食管鳞癌(esophageal squamous cell carcinoma,ESCC)与食管腺癌(esophageal adenocarcinoma,EAC)的基因差异表达,探讨ESCC与EAC发生发展的基因学基础。方法:选取8例ESCC和8例EAC组织抽提mRNA,应用cDNA芯片技术通过芯片杂交、生物信息学处理,找出两者间差异表达基因。结果:采用BioStarH-40芯片发现差异表达基因541条,差异表达基因占13.8%,其中表达增强309条(显著增强73条),表达降低232条(显著降低61条)。结论:ESCC与EAC基因表达比较,差异有统计学意义,这些差异可能在两类肿瘤不同的生物学行为中起重要作用。     

食管鳞癌与腺癌差异基因表达的对比分析

目的：研究食管鳞癌（esophageal squamous cell carcinoma,ESCC）与食管腺癌（esophageal adenocarcinoma,EAC）的基因差异表达,探讨ESCC与EAC发生发展的基因学基础。方法：选取8例ESCC和8例EAC组织抽提mRNA,应用cDNA芯片技术通过芯片杂交、生物信息学处理,找出两者间差异表达基因。结果：采用BioStarH-40芯片发现差异表达基因541条,差异表达基因占13．8％,其中表达增强309条（显著增强73条）,表达降低232条（显著降低61条）。结论：ESCC与EAC基因表达比较,差异有统计学意义,这些差异可能在两类肿瘤不同的生物学行为中起重要作用。     

Skp2和P27在食管鳞状细胞癌中表达及其临床意义

目的:研究S期激酶相关蛋白2(Skp2)与细胞周期素抑制因子P27在人食管鳞状细胞癌中蛋白冰平的表达差异,分析二基因的相互关系及其与食管鳞癌浸润深度、组织学分级、淋巴结转移等临床病理因素间的关系,探讨Skp2和P27在食管鳞癌发生发展过程中的作用及其临床意义.方法:应用免疫组化检测49例食管鳞癌及其切缘正常组织中Skp2和P27的表达,用PearsonX<'2>检验分析二者的表达在两组间是否有差别;用Pearson X<'2>检验和Fisher's确切概率法分析Skp2和P27表达与食管鳞癌患者性别、年龄、临床分期、病理组织学分级、淋巴结转移等临床病理因素间的关系;用Pearson相关系数分析食管鳞癌中Skp2和P27两者表达的相关性;结果:Skp2在食管鳞癌及其切缘正常粘膜组织中的阳性表达率分别为57.1%和20.0%,(P<0.05).P27在食管鳞癌及其切缘正常粘膜组织中的阳性表达率分别为51.0%和85.0%,(P<0.05).Skp2和P27的表达与临床分期、组织学分级、淋巴结转移显著相关,与患者性别、年龄无显著相关,且二者在食管鳞癌中表达呈显著负相关.结论:食管鳞癌中Skp2基因在蛋白水平高表达,在切缘正常粘膜组织中低表达,P27蛋白表达与Skp2蛋白表达之间呈负相关.Skp2和P27表达与食管鳞癌肿瘤临床分期、组织学分级、淋巴结转移等临床病理因素密切相关.     

Localization of p21-Activated Kinase 1 (PAK1) to Pinocytic Vesicles and Cortical Actin Structures in Stimulated Cells

Pex mutants of the yeast Yarrowia lipolytica are defective in peroxisome assembly. The mutant strain pex16-1 lacks morphologically recognizable peroxisomes. Most peroxisomal proteins are mislocalized to a subcellular fraction enriched for cytosol in pex16 strains, but a subset of peroxisomal proteins is localized at, or near, wild-type levels to a fraction typically enriched for peroxisomes. The PEX16 gene was isolated by functional complementation of the pex16-1 strain and encodes a protein, Pex16p, of 391 amino acids (44,479 D). Pex16p has no known homologues. Pex16p is a peripheral protein located at the matrix face of the peroxisomal membrane. Substitution of the carboxylterminal tripeptide Ser-Thr-Leu, which is similar to the consensus sequence of peroxisomal targeting signal 1, does not affect targeting of Pex16p to peroxisomes. Pex16p is synthesized in wild-type cells grown in glucose-containing media, and its levels are modestly increased by growth of cells in oleic acid–containing medium. Overexpression of the PEX16 gene in oleic acid– grown Y. lipolytica leads to the appearance of a small number of enlarged peroxisomes, which contain the normal complement of peroxisomal proteins at levels approaching those of wild-type peroxisomes.     

Tenascin-C,a Prognostic Determinant of Esophageal Squamous Cell Carcinoma

Background

Tenascin-C, an adhesion modulatory extracellular matrix molecule, is highly expressed in numerous human malignancies; thus, it may contribute to carcinogenesis and tumor progression. We explored the clinicopathological significance of Tenascin-C as a prognostic determinant of esophageal squamous cell carcinoma (ESCC).

Methods

In ESCC patient tissues and cell lines, the presence of isoforms were examined using western blotting. We then investigated Tenascin-C immunohistochemical expression in 136 ESCC tissue samples. The clinical relevance of Tenascin-C expression and the correlation between Tenascin-C expression and expression of other factors related to cancer-associated fibroblasts (CAFs) were also determined.

Results

Both 250 and 350 kDa sized isoforms of Tenascin-C were expressed only in esophageal cancer tissue not in normal tissue. Furthermore, both isoforms were also identified in all of four CAFs derived from esophageal cancer tissues. Tenascin-C expression was remarkably higher in ESCC than in adjacent non-tumor esophageal epithelium (p < 0.001). Tenascin-C expression in ESCC stromal fibroblasts was associated with patient’s age, tumor (pT) stage, lymph node metastasis, clinical stage, and cancer recurrence. Tenascin-C expression in cancer cells was correlated with an increase in tumor-associated macrophage (TAM) population, cancer recurrence, and hypoxia inducible factor1α (HIF1α) expression. Moreover, Tenascin-C overexpression in cancer cells and stromal fibroblasts was an independent poor prognostic factor for overall survival (OS) and disease-free survival (DFS). In the Cox proportional hazard regression model, Tenascin-C overexpression in cancer cells and stromal fibroblasts was a significant independent hazard factor for OS and DFS in ESCC patients in both univariate and multivariate analyses. Furthermore, Tenascin-C expression in stromal fibroblasts of the ESCC patients was positively correlated with platelet-derived growth factor α (PDGFRα), PDGFRβ, and smooth muscle actin (SMA) expression. The 5-year OS and DFS rates were remarkably lower in patients with positive expressions of both Tenascin-C and PDGFRα (p < 0.001), Tenascin-C and PDGFRβ (p < 0.001), Tenascin-C and SMA (p < 0.001), Tenascin-C and fibroblast activation protein (FAP) (p < 0.001), and Tenascin-C and fibroblast-stimulating protein-1 (FSP1) (p < 0.001) in ESCC stromal fibroblasts than in patients with negative expressions of both Tenascin-C and one of the abovementioned CAF markers.

Conclusion

Our results show that Tenascin-C is a reliable and significant prognostic factor in ESCC. Tenascin-C may thus be a potent ESCC therapeutic target.     

GRP78 在食管鳞状细胞癌、不典型增生及正常食管鳞状上皮 组织中的表达

目的:检测葡萄糖调节蛋白78(glucose-regulated proteins 78,GRP78)在同一食管癌患者食管的鳞状细胞癌、不典型增生及正常鳞状上皮组织中的表达,研究GRP78与食管鳞状细胞癌发生发展的关系。方法:取90例食管鳞状细胞癌患者的病变组织,其病理切片中正常鳞状上皮组织、不典型增生组织和鳞状细胞癌组织均存在,用免疫组化的方法 ,检测GRP78在3种不同组织中表达的情况,分析GRP78与性别、年龄、浸润深度、分化程度、分期及淋巴结转移等参数之间的关系。结果:GRP78在食管正常鳞状上皮组织、不典型增生组织、鳞状细胞癌组织中的阳性表达率分别为7.8%、85.6%、47.8%,GRP78在正常食管组织、不典型增生组织、食管鳞癌组织3组中表达的差异有显著性意义(P<0.01)。鳞状细胞癌组织中GRP78表达阴性者,年龄较阳性者大;GRP78表达与肿瘤分化程度、分期、淋巴结转移等有明显相关性。结论:GRP78在食管正常细胞向恶性细胞转化的过程中可能扮演了重要角色,检测GRP78的表达可能有助于对食管鳞状细胞癌的预防及早期诊断。     

GRP78在食管鳞状细胞癌、不典型增生及正常食管鳞状上皮组织中的表达

目的：检测葡萄糖调节蛋白78（glucose—regulated proteins78,GRP78）在同一食管癌患者食管的鳞状细胞癌、不典型增生及正常鳞状上皮组织中的表达,研究GRP78与食管鳞状细胞癌发生发展的关系。方法：取90例食管鳞状细胞癌患者的病变组织,其病理切片中正常鳞状上皮组织、不典型增生组织和鳞状细胞癌组织均存在,用免疫组化的方法,检测GRP78在3种不同组织中表达的情况,分析G史P78与性别、年龄、浸润深度、分化程度、分期及淋巴结转移等参数之间的关系。结果：GRP78在食管正常鳞状上皮组织、不典型增生组织、鳞状细胞癌组织中的阳性表达率分别为7．8％、85．6％、47．8％,GRP78在正常食管组织、不典型增生组织、食管鳞癌组织3组中表达的差异有显著性意义（P〈0．01）。鳞状细胞癌组织中GRP78表达阴性者,年龄较阳性者大;GRP78表达与肿瘤分化程度、分期、淋巴结转移等有明显相关性。结论：GRP78在食管正常细胞向恶性细胞转化的过程中可能扮演了重要角色,检测GRP78的表达可能有助于对食管鳞状细胞癌的预防及早期诊断。     

Mitogen-activated Protein Kinase Signaling Mediates Phosphorylation of Polycomb Ortholog Cbx7

Cbx7 is one of five mammalian orthologs of the Drosophila Polycomb. Cbx7 recognizes methylated lysine residues on the histone H3 tail and contributes to gene silencing in the context of the Polycomb repressive complex 1 (PRC1). However, our knowledge of Cbx7 post-translational modifications remains limited. Through combined biochemical and mass spectrometry approaches, we report a novel phosphorylation site on mouse Cbx7 at residue Thr-118 (Cbx7T118ph), near the highly conserved Polycomb box. The generation of a site-specific antibody to Cbx7T118ph demonstrates that Cbx7 is phosphorylated via MAPK signaling. Furthermore, we find Cbx7T118 phosphorylation in murine mammary carcinoma cells, which can be blocked by MEK inhibitors. Upon EGF stimulation, Cbx7 interacts robustly with other members of PRC1. To test the role of Cbx7T118 phosphorylation in gene silencing, we employed a RAS-induced senescence model system. We demonstrate that Cbx7T118 phosphorylation moderately enhances repression of its target gene p16. In summary, we have identified and characterized a novel MAPK-mediated phosphorylation site on Cbx7 and propose that mitogen signaling to the chromatin template regulates PRC1 function.     

VEGF-A在食管鳞状细胞癌中的表达及临床意义

目的:探讨血管内皮生长因子A(VEGF-A)在食管鳞状细胞癌中的表达及临床意义。方法:收集2009年1月-2010年12月收治的45例食管鳞状细胞癌患者临床资料及病理标本,应用免疫组织化学法检测肿瘤组织VEGF-A表达及微淋巴管密度(MLVD),分析VEGF-A表达与食管鳞癌患者临床病理资料、MLVD及与患者生存期限的关系。结果:1有淋巴结转移的患者VEGF-A表达阳性率为66.67%,明显高于无淋巴结转移患者的38.10%(P0.05);2 VEGF-A阳性食管鳞状细胞癌患者MLVD为(8.35±2.45)明显高于阴性患者的(5.32±1.44),(P0.05);3VEGF-A阳性食管鳞状细胞癌患者3年存活率为41.67%明显低于阴性患者的61.90%(P0.05)。结论:VEGF-A表达在确定早期食管鳞状细胞癌淋巴结转移方面具有一定的应用价值,可以作为评价预后的有效指标。     

Substrate and Inhibitor Specificity of the Type II p21-Activated Kinase,PAK6

The p21-activated kinases (PAKs) are important effectors of Rho-family small GTPases. The PAK family consists of two groups, type I and type II, which have different modes of regulation and signaling. PAK6, a type II PAK, influences behavior and locomotor function in mice and has an ascribed role in androgen receptor signaling. Here we show that PAK6 has a peptide substrate specificity very similar to the other type II PAKs, PAK4 and PAK5 (PAK7). We find that PAK6 catalytic activity is inhibited by a peptide corresponding to its N-terminal pseudosubstrate. Introduction of a melanoma-associated mutation, P52L, into this peptide reduces pseudosubstrate autoinhibition of PAK6, and increases phosphorylation of its substrate PACSIN1 (Syndapin I) in cells. Finally we determine two co-crystal structures of PAK6 catalytic domain in complex with ATP-competitive inhibitors. We determined the 1.4 Å co-crystal structure of PAK6 with the type II PAK inhibitor PF-3758309, and the 1.95 Å co-crystal structure of PAK6 with sunitinib. These findings provide new insights into the structure-function relationships of PAK6 and may facilitate development of PAK6 targeted therapies.