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1.
为了研究蛋白激酶C(PKC)和乳腺癌分化及转移的相关性,采用免疫组化SABC方法检测48例人乳腺癌的PKC蛋白表达,包括PKCα、βI、η和ξ等蛋白。结果表明,与分化低的乳腺癌对比,分化高的乳腺癌PKC蛋白表达水平提高。在临床I-II和III级的乳腺癌中,PKCη蛋白表达率分别为61.5%和9.1%,具有显著意义(P<0.05),PKCξ蛋白表达率分别为92.3%和27.3%,具有极显著意义(P<0.01)。另外,在乳腺癌未转移的病例中,PKCs蛋白表达水平普遍较高,其中PKCξ与肿转移相关性极显著(P<0.01)。此外,PKCs蛋白表达水平与肿瘤患者年龄无关。以上结果提示,PKCη和PKCξ有可能作为评价临床乳腺癌分化和转移程度的指标之一。  相似文献   
2.
Summary The biochemical development of the fetal brain in relation to maternal vitamin A restriction was studied in rats. The vitamin A status of pregnant rats was varied by supplying low, medium and adequate amounts (6, 40, and 100 g retinol/day/kg body weight, respectively) of vitamin A during pregnancy and suckling. The maternal vitamin A restriction caused an altered brain development in terms of tissue weight, DNA, RNA and protein levels, and biosynthesis of DNA and protein from [3H]-thymidine and [3H]-leucine, respectively. A dose-dependent effect of maternal vitamin A restriction on the metabolism of DNA, RNA and protein was noticed in the developing fetal brain of rats.  相似文献   
3.
MMP-2、MMP-9及其抑制剂在肺癌中的表达与临床意义   总被引:1,自引:0,他引:1  
目的探讨肺癌组织中MMP2、MMP9及其抑制剂的表达与肺癌的生长、转移等临床特征及预后的关系.方法采用免疫组织化学法SP法检测45例肺癌组织中MMP2、MMP9及其抑制剂的表达,观察它们与肺癌的生长、TMN分期的关系.结果MMP2、MMP9、TIMP1和TIMP2在45例肺癌组织中的阳性表达率分别为57.78%(26/45)、37.78%(17/45)、35.56%(16/45)及51.11%(23/45);它们的表达与肺癌的原发灶范围、淋巴结转移、远处转移、TNM分期及平均生存时间有统计学意义(P<0.05).结论MMP2、MMP9及其抑制剂的表达与肺癌的TNM分期及平均生存时间关系密切,它们在组织中的高表达是判断肺癌预后的独立因素.  相似文献   
4.
目的:研究益肾骨康方对骨转移癌疼痛大鼠脊髓背角GFAP、c-fos、P物质蛋白表达的调控作用。方法:在裸鼠肺腺癌溶骨性骨转移模型的基础上,采用免疫组织化学染色的方法,分别观察各组裸鼠脊髓背角GFAP、c-fos、P物质等蛋白的表达。并使用MIA4.0图像分析软件进行图像分析,每张切片取五个视野,显微镜放大倍数为400倍,统计每个高倍镜视野中表达的阳性物质的光密度值。结果:模型组裸鼠发生了100%的骨转移,免疫组织化学结果显示模型组脊髓背角GFAP、c-fos、P物质蛋白过表达;而“益肾骨康方”低剂量组与中 西药组裸鼠未发生骨转移,免疫组织化学结果显示GFAP、c-fos、P物质蛋白的表达处于较低的水平(P<0.01);“益肾骨康方”中、高剂量组裸鼠也发生了骨转移,但是这两组裸鼠脊髓背角GFAP、c-fos、P物质蛋白等与疼痛相关的蛋白表达明显低于模型组(P<0.05)。结论:“益肾骨康方”可能通过抑制裸鼠脊髓背角GFAP、c-fos、P物质等蛋白的表达,从而抑制肺腺癌细胞的骨侵袭与转移所引起的疼痛,即“益肾骨康方”通过抑制裸鼠脊髓背角GFAP、c-fos、P物质蛋白的表达而起到一定的镇痛作用。  相似文献   
5.
目的:探讨骨桥蛋白(OPN)在卵巢肿瘤组织的表达及其与恶性肿瘤侵袭转移的关系。方法:采用免疫组织化学方法测定OPN在48例卵巢恶性肿瘤组织、8例卵巢临界恶性肿瘤组织、20例卵巢良性肿瘤组织及10例卵巢正常组织中的表达。结果:OPN在卵巢恶性肿瘤组织表达强度为0.485±0.134,显著高于卵巢正常组织及卵巢临界恶性及良性肿瘤组织表达强度(0.122±0.023,0.243±0.076及0.168±0.045,P<0.01);OPN的表达与恶性肿瘤的临床期别及分化程度相关,而与细胞组织学类型无关。结论:OPN在卵巢肿瘤的发生发展中起重要作用,并与卵巢恶性肿瘤的侵袭转移相关。  相似文献   
6.
Increasing evidence implies altered signaling through the neurotrophic receptor tyrosine kinase TrkB in promoting tumor formation and metastasis. TrkB, sometimes in conjunction with its primary ligand BDNF, is often overexpressed in a variety of human cancers, ranging from neuroblastomas to pancreatic ductal adenocarcinomas, in which it may allow tumor expansion and contribute to resistance to anti-tumor agents. In vitro, TrkB acts as a potent suppressor of anoikis (detachment-induced apoptosis), which is associated with the acquisition of an aggressive tumorigenic and metastatic phenotype in vivo. In view of its predicted contribution to tumorigenicity and metastasis in humans, TrkB corresponds to a potential drug target, and preclinical models have already been established. The encouraging results of pharmacological Trk inhibitors in tumor xenograft models suggest that TrkB inhibition may represent a promising novel anti-tumor therapeutic strategy. This hypothesis is currently being evaluated in clinical trials. Here, we will discuss the latest developments on TrkB in these contexts as well as highlight some critical questions that remain to be addressed for evaluating TrkB as a therapeutic target in cancer. Received 12 October 2005; received after revision 19 December 2005; accepted 11 January 2006  相似文献   
7.
在36℃培育的小白鼠脑切片对~3H-GABA的摄取是浓度依赖性的、可饱和的,当2ml培育液中注入100μl浓度为215×10~(-4)mol/L的~3H-GABA时,脑片对~3H-GABA的摄取达到饱和。3℃时切制脑片能获得较好的~3H-GABA摄取效果。苄青霉素钾(PG)7.6×10~(-4)mol/L、苯巴比妥钠(PhB)9.8×10~(-4)mol/L、Gabaculline 4.0mol/L各100μl均使脑片对~3H-GABA的摄取明显下降,荷包牡丹碱(BiC)0.25×10~(-4)mol/L、氨氧乙酸(AOAAA)1.0×10~(-4)mol/L可使脑片对~3H-GABA的摄取明显上升。  相似文献   
8.
雌亚洲玉米螟Ostrinia furnacalis仅在黑暗期产生性信息素,性信息素的产生?脑中一种活性因子的控制,光照期、黑暗期的雌蛾脑匀浆液都有这种活性因子存在,但黑暗期脑匀浆活性较高,雄蛾脑匀浆液也有这种活性,雌大蜡螟Galleria mellonella脑匀浆液也对亚洲玉米螟雌蛾有刺激活性,保幼激素类似物ZR-512对亚洲玉米螟性信息素的产生即无刺激作用也无抑制作用。切断腹部末端神经亦不影响脑因子促使性信息素的产生和释放。  相似文献   
9.
HAb18G/CD147 is a heavily glycosylated protein containing two immunoglobulin superfamily domains. Our previous studies have indicated that overexpression of HAb18G/CD147 enhances metastatic potentials in human hepatoma cells by disrupting the regulation of store-operated Ca2+ entry by nitric oxide (NO)/cGMP. In the present study, we investigated the structure-function of HAb18G/CD147 by transfecting truncated HAb18G/CD147 fragments into human 7721 hepatoma cells. The inhibitory effect of HAb18G/CD147 on 8-bromo-cGMP-regulated thapsigargin-induced Ca2+ entry was reversed by the expression of either C or N terminus truncated HAb18G/CD147 in T7721C and T7721N cells, respectively. The potential effect of HAb18G/CD147 on metastatic potentials, both adhesion and invasion capacities, of hepatoma cells was abolished in T7721C cells, but not affected in T7721N cells. Release and activation of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were found to be enhanced by the expression of HAb18G/CD147, and this effect was abolished by both truncations. Thapsigargin significantly enhanced release and activation of MMPs (MMP-2 and MMP-9) in non-transfected 7721 cells, and this effect was negatively regulated by SNAP. However, no effects of thapsigargin or SNAP were observed in T7721 cells, and expression of HAb18G/CD147 enhanced secretion and activation of MMPs at a stable and high level. Taken together, these results suggest that both ectodomain and intracellular domains of HAb18G/CD147 are required to mediate the effect of HAb18G/CD147 on the secretion and activation of MMPs and metastasis-related processes in human hepatoma cells by disrupting the regulation of NO/cGMP-sensitive intracellular Ca2+ mobilization although each domain may play different roles.Received 1 April 2004; received after revision 15 June 2004; accepted 22 June 2004  相似文献   
10.
The Ras family of GTPases in cancer cell invasion   总被引:3,自引:0,他引:3  
The ability of tumoral cells to invade surrounding tissues is a prerequisite for metastasis. This is the most life-threatening event of tumor progression, and so research is intensely focused on elucidating the mechanisms responsible for invasion and metastasis. The Ras superfamily of GTPases comprises several subfamilies of small GTP-binding proteins whose functions include the control of proliferation, differentiation, and apoptosis, as well as cytoskeleton organization. The development of metastasis is a multistep process that requires coordinated activation of proliferation, motility, changes in normal cell-to-cell and cell-to-substrate contacts, degradation of extracellular matrix, inhibition of apoptosis, and adaptation to an inappropriate tissue environment. Several members of the Ras superfamily of proteins have been implicated in these processes. The present review summarizes the current knowledge in this field.  相似文献   
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