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991.
Longxi Mao Shilian Le Xin Jin Guoliang Liu Jun Chen Junwen Hu 《Experimental cell research》2019,374(2):274-281
COP9 signalosome subunit 5 (CSN5) has been involved in the progression of diverse human cancers. MMP2 plays an important role in the metastasis of cancer cells. However, the roles and relationship of in pancreatic cancer (PC) is still unknown. Here, our data shown that both CSN5 and MMP2 were significantly upregulated in PC compared with the corresponding adjacent tissues, where a positive correlation in their expression and associated malignant characteristics were found. Further, silencing of CSN5 expression markedly inhibited PC invasion and metastasis in vitro and in vivo, accompanied by decreased MMP2 expression. Moreover, the anti-metastasis role of CSN5 silence was reversed by MMP2 overexpression, whereas knockdown of MMP2 decreased PC metastasis driven by upregulation of CSN5. Further investigation revealed that CSN5 regulated MMP2 expression via activation of FOXM1 in PC cells. Mechanistically, CSN5 directly bound FOXM1 and decreased its ubiquitination to enhance the protein stability of FOXM1. Taken together, the results indicate that CSN5 can contribute to PC invasion and metastasis through activation of FOXM1/MMP2 axis. 相似文献
992.
端粒的生物学功能主要是保护染色体末端,避免核酸酶对染色体末端的降解,防止染色体之间发生融合和重排。大多数人类肿瘤细胞通常通过端粒酶活性的重新激活来延长端粒,从而稳定染色体端粒DNA的长度。端粒酶是由端粒酶逆转录酶和端粒酶RNA模板组成的具有特殊逆转录活性的核糖核蛋白复合物。抑制端粒酶阳性细胞中的端粒酶活性会导致细胞凋亡或衰老。目前有多种以端粒和端粒酶为靶点来进行肿瘤治疗的策略。 相似文献
993.
目的:探讨食管癌三维适形放疗前后肺功能、生活质量的变化及放射性肺炎的影响因素.方法:收集2017年11月~2019年11月在我院进行三维适形放疗的食管癌患者102例,对患者放疗前后的肺功能进行检测对比,并采用生活质量评价简袁(QLQ-C30)对患者放疗前后的生活质量进行评估对比.统计患者放疗后放射性肺炎的发生率,根据患... 相似文献
994.
Based on the very high prevalence of diseases caused by Helicobacter pylori, particularly in the developing world, and the rapid emergence of antibiotic resistance among clinical isolates, there is a strong rationale for an effective vaccine against H. pylori. In this review we describe recent promising candidate vaccines and prophylactic or therapeutic immunization strategies for use against H. pylori, as well as studies to identify immune responses that are related to protection in experimental animals. We also describe identification of different types of immune responses that may be related to protection against symptoms based on comparisons of H. pylori-infected patients with duodenal ulcers or gastric cancer and asymptomatic carriers. We conclude that there is still a strong need to clarify the main protective immune mechanisms against H. pylori as well as to identify a cocktail of strong protective antigens, or recombinant bacterial strains that express such antigens, that could be administered by a regimen that gives rise to effective immune responses in humans. 相似文献
995.
目的:汉黄芩素是中药黄芩中的一种黄酮,具有体内外抗癌活性。然而,汉黄芩素对人胃癌细胞的作用尚不十分清楚。本研究拟探讨汉黄芩素对人胃癌细胞MGC-803侵袭转移能力的影响及其对上皮间质转化(Epithelial to Mesenchymal Transition,EMT)的作用机制。方法:采用MTT法测定汉黄芩素对人胃癌细胞MGC-803增殖能力的影响,通过划痕实验、Transwell试验检测汉黄芩素对人胃癌细胞MGC-803迁移、侵袭能力的影响。通过免疫印迹法和免疫荧光法分析汉黄芩素对EMT的影响。结果:20μM以上浓度的汉黄芩素能抑制人胃癌细胞MGC-803的增殖,不同浓度的汉黄芩素能抑制人胃癌细胞MGC-803的迁移和侵袭,且呈浓度依赖性。此外,汉黄芩素能抑制间质标记蛋白波形蛋白(Vimentin)和锌指蛋白E-盒结合同源异形盒-1(ZEB1)的表达,促进上皮标记蛋白E-钙黏蛋白(E-cadherin)的表达。结论:汉黄芩素能抑制胃癌细胞的侵袭和迁移,这一作用可能与其抑制EMT的发生有关。 相似文献
996.
刘青山姜晨荆涛任禹霏刘军刘勇 《现代生物医学进展》2012,12(12):2352-2355
目的:探讨国人前列腺癌患者前列腺体积与肿瘤分级之间的关系。方法:回顾我院及武汉大学人民医院2005年1月-2011年10月70例确诊为前列腺癌并行根治性前列腺切除术(RP)患者的临床病理资料,采用SPSS13.0软件总结并分析前列腺癌患者前列腺体积与肿瘤分级之间的关系。结果:经直肠前列腺穿刺活检获得肿瘤病理分级与根治性前列切除术获得最终病理分级具有显著差异(P=0.003);在活检及根治性前列腺切除标本中,前列腺体积与高级别肿瘤发生率均呈负相关(P<0.05);小前列腺与阳性手术切缘、前列腺外侵犯及高级别肿瘤在单变量分析中具有相关性(P<0.05),而与精囊腺侵犯及淋巴结侵犯则无相关性(P>0.05);在校正了年龄、体重指数及术前前列腺特异性抗原水平后,前列腺体积与阳性手术切缘、前列腺外侵犯、精囊腺侵犯及高级别肿瘤发生率均呈负相关(OR<1,P<0.05),而与淋巴结侵犯则无相关性(P>0.05)。结论:前列腺体积是高级别前列腺癌的重要预测因子,利用其对高级别肿瘤风险的预测能力可帮助选择最佳治疗方案并进一步提高治疗效果。 相似文献
997.
C Goswami 《Journal of neurochemistry》2012,123(1):1-13
Existence of microtubule cytoskeleton at the membrane and submembranous regions, referred as 'membrane tubulin' has remained controversial for a long time. Since we reported physical and functional interaction of Transient Receptor Potential Vanilloid Sub Type 1 (TRPV1) with microtubules and linked the importance of TRPV1-tubulin complex in the context of chemotherapy-induced peripheral neuropathy, a few more reports have characterized this interaction in in vitro and in in vivo condition. However, the cross-talk between TRPs with microtubule cytoskeleton, and the complex feedback regulations are not well understood. Sequence analysis suggests that other than TRPV1, few TRPs can potentially interact with microtubules. The microtubule interaction with TRPs has evolutionary origin and has a functional significance. Biochemical evidence, Fluorescence Resonance Energy Transfer analysis along with correlation spectroscopy and fluorescence anisotropy measurements have confirmed that TRPV1 interacts with microtubules in live cell and this interaction has regulatory roles. Apart from the transport of TRPs and maintaining the cellular structure, microtubules regulate signaling and functionality of TRPs at the single channel level. Thus, TRPV1-tubulin interaction sets a stage where concept and parameters of 'membrane tubulin' can be tested in more details. In this review, I critically analyze the advancements made in biochemical, pharmacological, behavioral as well as cell-biological observations and summarize the limitations that need to be overcome in the future. 相似文献
998.
张汉园沈丽萍曹风华施瑜盈丽霞 《现代生物医学进展》2012,12(20):3876-3878
目的:探讨乳头瘤病毒定性检测( HPV- DNA)与液基薄层细胞学检查技术(TCT)在宫颈癌前病变中的诊断价值.方法:分别采用HPV- DNA及TCT法检测1536例患者,对TCT阳性、HPV- DNA阳性病例者进行阴道镜下活检.结果:随着病理诊断级别的升高,高危型HPV感染率上升,而低危型HPV感染多见于轻度不典型增生(CINⅠ)及其以下病变,HPV混合感染在各组间未见明显趋势.HPV-DNA检测与宫颈活检的符合率为66.78%.随着病理级别的升高,不典型鳞状细胞(ASCUS)组的感染率呈降低趋势,鳞状上皮内低度病变(LSIL)组感染率亦呈下降趋势,而鳞状上皮内高度病变(HSIL)组和鳞癌(SCC)组感染率均呈上升趋势,TCT检测与组织学诊断的符合率为66.67%,与HPV-DNA检查比较,差异无统计学意义(x=0.001,P>0.05).结论:HPV-DNA、TCT及宫颈活检三者检测相结合,能明显提高诊断的正确性. 相似文献
999.
Ska2(spindle and kinetochore associated complex subunit2),又称FAM33A(family with sequence similarity33,member A),是新近发现的一个与细胞周期调控和肿瘤发生发展紧密相关的基瓯且与该团队前期发现的新基NPRR11(proline rich 11)共享一个双向启动子。但是,Ska2在肺癌中的具体作用和分子机制仍不清楚。该研究选用肺癌细胞系H1299,采用RNAi技术构建Ska2基因沉默的稳定细胞株,并进行了细胞表型和潜在分子机制分析。RT-PCR和Western blot结果表明,Ska2在mRNA和蛋白质水平上的表达均被有效抑制。细胞增殖、细胞迁移和侵袭实验结果表明,与对照细胞相比,Ska2基因沉默稳定细胞株的细胞增殖能力、细胞迁移和侵袭能力均显著降低。此外,Ska2基因被沉默后,CCNA1基因的表达显著下调。该研究的结果提示,Ska2与其对侧基因PRR11的功能高度相关,可能与PRR11共同参与肺癌细胞增殖、迁移和侵袭行为的调节。 相似文献
1000.
Diane L Rossi Edmund A Rossi Thomas M Cardillo David M Goldenberg Chien-Hsing Chang 《MABS-AUSTIN》2014,6(2):381-391
Various constructs of bispecific antibodies (bsAbs) to redirect effector T cells for the targeted killing of tumor cells have shown considerable promise in both preclinical and clinical studies. The single-chain variable fragment (scFv)-based formats, including bispecific T-cell engager (BiTE) and dual-affinity re-targeting (DART), which provide monovalent binding to both CD3 on T cells and to the target antigen on tumor cells, can exhibit rapid blood clearance and neurological toxicity due to their small size (~55 kDa). Herein, we describe the generation, by the modular DOCK-AND-LOCKTM (DNLTM) method, of novel T-cell redirecting bispecific antibodies, each comprising a monovalent anti-CD3 scFv covalently conjugated to a stabilized dimer of different anti-tumor Fabs. The potential advantages of this design include bivalent binding to tumor cells, a larger size (~130 kDa) to preclude renal clearance and penetration of the blood-brain barrier, and potent T-cell mediated cytotoxicity. These prototypes were purified to near homogeneity, and representative constructs were shown to provoke the formation of immunological synapses between T cells and their target tumor cells in vitro, resulting in T-cell activation and proliferation, as well as potent T-cell mediated anti-tumor activity. In addition, in vivo studies in NOD/SCID mice bearing Raji Burkitt lymphoma or Capan-1 pancreatic carcinoma indicated statistically significant inhibition of tumor growth compared with untreated controls. 相似文献