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31.
目的 探讨COX-2基因与基质金属蛋白酶在星形细胞瘤中的表达及二者相关性。方法 用原位杂交的方法检测星形细胞瘤组织中COX-2 mRNA的表达;用Ultrasensitive S-P法(链霉素抗生物素蛋白-过氧化物免疫组化染色)检测同等标本中基质金属蛋白酶-2和基质金属蛋白酶-9蛋白的表达;并将COX-2 mRNA与基质金属蛋白酶的表达作相关性分析。结果 COX-2 mRNA及MMP2、MMP9在星形细胞瘤中高度表达,表达阳性率分别为62.69%、56.70%和58.20%;COX-2 mRNA与MMP2和MMP9均有正相线性关系,Pearson积距相关系数分别为0.260、0.347,P<0.05。结论 COX-2基因和基质金属蛋白酶在星形细胞瘤组织中的表达密切相关,说明它在星形细胞瘤向周围组织侵袭中起重要作用。 相似文献
32.
【摘要】 目的 探讨基质金属蛋白酶抑制剂(RECK)、基质金属蛋白酶 9(MMP 9)在三阴性乳腺癌(TNBC)组织、癌旁组织中的表达及与TNBC临床病理的关系。方法 选择绵阳市中心医院乳腺外科2011年5月~2013年7月经病理证实为TNBC的72例石蜡标本及同 患者癌旁组织,利用免疫组化组织芯片技术检测其RECK、MMP 9蛋白的表达。结果 RECK在TNBC组织及癌旁组织中阳性表达率分别为4306%、8056%(P=0000)。TNBC中RECK的表达与临床分期(P=0009)、组织学分级(P=0010)、腋窝淋巴结转移情况(P=0000)相关。MMP 9在TNBC组织及癌旁组织中阳性表达率分别为625%、1528%(P=0000)。TNBC中MMP 9的表达与肿瘤大小(P=0017)、临床分期(P=0001)、组织学分级(P=0001)、腋窝淋巴结转移状况(P=0001)、Ki 67表达情况(P=0034)相关。TNBC中RECK与MMP 9表达呈负相关(r= 0195,P<005)。结论 RECK的表达缺失与MMP 9过度表达与TNBC浸润、转移有关,有望成为TNBC的预后指标,并且有可能成为TNBC治疗的靶点。 相似文献
33.
目的立足于肿瘤转移的生物学特性与痰的病理特征相似基础上,探讨痰在肿瘤转移中发挥作用的可能物质基础。方法以酶联免疫吸附法检测胃癌痰湿证型患者30例治疗前后与非痰湿证型患者32例以及健康对照组10例血清中上皮钙黏附分子(E-Cad)、基质金属蛋白酶(MMP9)的表达;痰湿证组服用消痰散结方1个月,非痰湿证组不治疗。观察治疗前后血清中E-Cad、MMP9的表达变化,并与非痰湿组血清中E-Cad、MMP9的表达进行比较对照。结果两种黏附分子表达在痰湿证型与非痰湿证型中的表达均较健康组升高(P<0.05),痰湿组较非痰湿组升高(P<0.05);治疗组治疗后E-Cad的表达明显降低(P<0.05),MMP9的表达有降低趋势,但差异不显著。结论痰在肿瘤转移中发挥作用的途径可能是通过影响黏附分子的表达,两者存在相关性。 相似文献
34.
Yangyang Hu Shengpeng Wang Xu Wu Jinming Zhang Ruie Chen Meiwan Chen Yitao Wang 《Journal of ethnopharmacology》2013
Ethnopharmacological relevance
Hepatocellular carcinoma (HCC) as the major histological subtype of primary liver cancer remains one of the most common malignancies worldwide. Due to the complicated molecular pathogenesis of HCC, the option for effective systemic treatment is quite limited. There exists a critical need to explore and evaluate possible alternative strategies for effective control of HCC. With a long history of clinical use, Chinese herbal medicine (CHM) is emerging as a noticeable choice for its multi-level, multi-target and coordinated intervention effects against HCC. With the aids of phytochemistry and molecular biological approaches, in the past decades many CHM-derived compounds have been carefully studied through both preclinical and clinical researches and have shown great potential in novel anti-HCC natural product development. The present review aimed at providing the most recent developments on anti-HCC compounds derived from CHM, especially their underlying pharmacological mechanisms.Materials and methods
A systematic search of anti-HCC compounds from CHM was carried out focusing on literatures published both in English (PubMed, Scopus, Web of Science and Medline) and in Chinese academic databases (Wanfang and CNKI database).Results
In this review, we tried to give a timely and comprehensive update about the anti-HCC effects and targets of several representative CHM-derived compounds, namely curcumin, resveratrol, silibinin, berberine, quercetin, tanshinone II-A and celastrol. Their mechanisms of anti-HCC behaviors, potential side effects or toxicity and future research directions were discussed.Conclusion
Herbal compounds derived from CHM are of much significance in devising new drugs and providing unique ideas for the war against HCC. We propose that these breakthrough findings may have important implications for targeted-HCC therapy and modernization of CHM. 相似文献35.
Secretion of matrix metalloproteinase‐3 by co‐cultured pigmented and non‐pigmented human trabecular meshwork cells following selective laser trabeculoplasty
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36.
Astrocytes in the damaged brain: Molecular and cellular insights into their reactive response and healing potential 总被引:1,自引:0,他引:1
Long considered merely a trophic and mechanical support to neurons, astrocytes have progressively taken the center stage as their ability to react to acute and chronic neurodegenerative situations became increasingly clear. Reactive astrogliosis starts when trigger molecules produced at the injury site drive astrocytes to leave their quiescent state and become activated. Distinctive morphological and biochemical features characterize this process (cell hypertrophy, upregulation of intermediate filaments, and increased cell proliferation). Moreover, reactive astrocytes migrate towards the injured area to constitute the glial scar, and release factors mediating the tissue inflammatory response and remodeling after lesion. A novel view of astrogliosis derives from the finding that subsets of reactive astrocytes can recapitulate stem cell/progenitor features after damage, fostering the concept of astroglia as a promising target for reparative therapies. But which biochemical/signaling pathways modulate astrogliosis with respect to both the time after injury and the type of damage? Are reactive astrocytes overall beneficial or detrimental for neuroprotection and tissue regeneration? This debate has been animating this research field for several years now, and an integrated view on the results obtained and the possible future perspectives is needed. With this Commentary article we have attempted to answer the above-mentioned questions by reviewing the current knowledge on the molecular mechanisms controlling and sustaining the reaction of astroglia to injury and its stem cell-like properties. Moreover, the cellular/molecular mechanisms supporting the detrimental or beneficial features of astrogliosis have been scrutinized to gain insights on possible pharmacological approaches to enhance astrocyte neuroprotective activities. 相似文献
37.
MMP3与TIMP2蛋白在宫颈癌中的表达及意义 总被引:3,自引:0,他引:3
目的探讨基质金属蛋白酶子(MMP3)与基质金属蛋白酶抑制因子(TIMP2)蛋白在宫颈癌组织中表达、相互关系及意义。方法采用免疫组化学S-P法检测46例宫颈癌、20例宫颈上皮内瘤变(CIN)和10例宫颈良性病变上皮组织中MMP3及TIMP2的表达情况。结果宫颈癌组织中MMP3表达水平高于CIN及宫颈良性病变上皮(P〈0.05),而TIMP2蛋白表达水平低于CIN及宫颈良性病变上皮(P〈0.05);MMP3的阳性表达率与宫颈癌分化程度、淋巴结转移有关(P〈0.05),与患者年龄、组织类型及临床分期无关(P〉0.05);TIMP2的阳性表达率与宫颈癌分化程度及淋巴结转移有关(P〈0.05),与患者年龄、组织类型、临床分期无关(P〉0.05);结论MMP3与TIMP2的表达程度与宫颈癌的发生发展密切相关,二者的比例失衡可能与宫颈癌的临床分期有关系。 相似文献
38.
39.
l-Theanine prevents alcoholic liver injury through enhancing the antioxidant capability of hepatocytes 总被引:1,自引:0,他引:1
Li G Ye Y Kang J Yao X Zhang Y Jiang W Gao M Dai Y Xin Y Wang Q Yin Z Luo L 《Food and chemical toxicology》2012,50(2):363-372
l-Theanine is a unique amino acid in green tea. We here evaluated the protective effects of l-theanine on ethanol-induced liver injury in vitro and in vivo. Our results revealed that l-theanine significantly protected hepatocytes against ethanol-induced cell cytotoxicity which displayed by decrease of viability and increase of LDH and AST. Furthermore, the experiments of DAPI staining, pro-caspase3 level and PARP cleavage determination indicated that l-theanine inhibited ethanol-induced L02 cell apoptosis. Mechanically, l-theanine inhibited loss of mitochondrial membrane potential and prevented cytochrome c release from mitochondria in ethanol-treated L02 cells. l-Theanine also prevented ethanol-triggered ROS and MDA generation in L02 cells. l-Theanine restored the antioxidant capability of hepatocytes including GSH content and SOD activity which were reduced by ethanol. In vivo experiments showed that l-theanine significantly inhibited ethanol-stimulated the increase of ALT, AST, TG and MDA in mice. Histopathological examination demonstrated that l-theanine pretreated to mice apparently diminished ethanol-induced fat droplets. In accordance with the in vitro study, l-theanine significantly inhibited ethanol-induced reduction of mouse antioxidant capability which included the activities of SOD, CAT and GR, and level of GSH. These results indicated that l-theanine prevented ethanol-induced liver injury through enhancing hepatocyte antioxidant abilities. 相似文献
40.
Sanchez C Mathy-Hartert M Deberg MA Ficheux H Reginster JY Henrotin YE 《Biochemical pharmacology》2003,65(3):377-388
This study was designed to investigate the effects of rhein, the active metabolite of diacerhein, on the metabolic functions of human chondrocytes cultured in alginate beads.Enzymatically isolated osteoarthritic (OA) chondrocytes were cultured in alginate beads in a well-defined culture medium for 12 days. Rhein was tested in a range of concentrations comprised between 10(-7) and 4 x 10(-5)M, in the presence or absence of 10(-10)M IL-1beta. Interleukin (IL)-6 and -8, macrophage inflammatory protein (MIP-1beta), stromelysin-1 (MMP-3), aggrecan (AGG), tissue inhibitor of metalloproteinases-1 (TIMP-1), prostaglandin E(2) (PGE(2)) and nitric oxide (NO) productions were assayed. Cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS) mRNA steady-state levels were also quantified. In the basal condition, 10(-5)M rhein increased by 46.5% the production of AGG, decreased by 17-30% the production of IL-6, MMP-3, NO and MIP-1beta but enhanced by 50% the production of PGE(2). IL-1beta increased IL-6, IL-8, MIP-1beta, NO, PGE(2) and MMP-3 productions, but inhibited AGG and TIMP-1 synthesis. Rhein partially reversed the effect of IL-1beta on TIMP-1 and NO production, had no effect on AGG, IL-6 and MIP-1beta production, but up-regulated the IL-1beta stimulated PGE(2) production. The COX-2 and iNOS mRNA levels and IL-8 production were not modified by rhein.Overall, these results contribute to explain the clinical efficiency of rhein and give new information on its mechanisms of action. 相似文献