PS-341对人大肠癌细胞LoVo,SW480中NF-κB、uPA表达的影响及其与侵袭力的关系

目的观察人大肠癌细胞LoVo、SW480中真核细胞转录因子-κB(NF-κB)、尿激酶型血浆纤溶酶原激活因子(uPA)的表达差异及硼替佐米(bortezomib,PS-341)对其表达的影响及其与侵袭力的关系。方法实验分为4组:对照组(无血清)、血清组(10%FCS)、PS-341组[10%FCS+PS-341(4ng/mL)]、PDTC(NF-κB抑制剂)组[10%FCS+PDTC(10-2 mol/L)]。Western-blot测定人大肠癌细胞LoVo、SW480中NF-κB、uPA的蛋白表达水平;Brdu ELISA法测定细胞增殖活性;Boyden小室培养测定细胞的迁移。结果 (1)与SW480细胞比较,血清组中LoVo细胞总NF-κB、核内NF-κB和uPA表达、细胞增殖及细胞迁移率均显著增高(P<0.05);(2)与对照组比较,血清组中2种细胞总NF-κB、核内NF-κB和uPA表达、细胞增殖及细胞迁移率均显著增高(P<0.05),其中LoVo细胞较SW480细胞增高更为显著(P<0.01);(3)与血清组比较,PS-341组与PDTC组中2种细胞总NF-κB、核内NF-κB和uPA表达、细胞增殖及细胞迁移率均显著降低(P<0.05),且LoVo细胞较SW480细胞降低更为显著(P<0.01);(4)与PS-341组比较,PDTC组中2种细胞总NF-κB、核内NF-κB和uPA表达、细胞增殖及细胞迁移均未见明显差别。结论 LoVo细胞较SW480细胞NF-κB、uPA呈高水平表达,其侵袭力高于SW480细胞可能与此有关;LoVo、SW480细胞uPA表达可能受NF-κB调控;PS-341可能通过降低NF-κB、uPA表达抑制LoVo、SW480细胞增殖与迁移;对LoVo细胞侵袭力抑制率高于SW480细胞可能与其对2种细胞NF-κB活性抑制程度不同有关。

PS-341对人乳腺癌MDA-MB231细胞uPA、NF-κB表达的影响及其与增殖迁移的关系

目的研究硼替佐米(bortezomib,PS-341)对人乳腺癌MDA-MB231细胞真核细胞转录因子-κB(nuclear factor-κB,NF-κB)、尿激酶型血浆纤溶酶原激活因子(uPA)表达的影响及其与增殖迁移的关系。方法 BRDU ELISA法测定细胞增殖活性;Boyden小室培养测定细胞的迁移;Western-blotting测定细胞uPA表达、NF-κB磷酸化水平。结果 1)与对照组(无血清培养基组)相比,血清组(FCS组)呈浓度依赖性促进细胞增殖;当FCS浓度为1%时,细胞增殖明显增加(P<0.05);当FCS浓度为5%时,细胞增殖更为显著(P<0.01)。2)与5%FCS组相比,PS-341呈浓度依赖性抑制细胞增殖活性,PS-341浓度为4ng/mL时细胞增殖活性显著下降(P<0.05)。3)与对照组相比,5%FCS组细胞迁移率明显升高(P<0.05);PS-341呈浓度依赖性抑制5%FCS诱导细胞的迁移,与5%FCS组相比PS-341浓度为4ng/mL时其迁移率显著下降。4)与5%FCS组相比,PS-341为4ng/mL时细胞uPA表达、总NF-κB、核NF-κB水平均明显降低(P<0.05);NF-κB特异性抑制剂PDTC(10μmol/L)能显著降低5%FCS诱导的总NF-κB、核NF-κB水平(P<0.05),但对uPA表达无影响。5)PS-341(4ng/mL)能明显降低5%FCS诱导细胞的增殖与迁移;与PDTC(10μmol/L)相比,两者差异均无统计学意义。结论 PS-341抑制MDA-MB231细胞uPA、NF-κB表达及增殖与迁移;PS-341降低MDA-MB231细胞侵袭力可能与其抑制NF-κB、uPA表达有关。

PI3K、NF-κB p65蛋白在宫颈癌组织中的表达及其临床意义

目的探讨磷脂酰肌醇-3-激酶(PI3K)、真核细胞转录因子κB(NF-κB)p65蛋白在宫颈癌组织中的表达及其临床意义。方法选取宫颈癌患者62例作为研究对象,提取宫颈癌组织及癌旁组织,采用免疫组织化学染色法检测PI3K和NF-κB p65蛋白的表达情况,对比宫颈癌组织和癌旁组织中REG4蛋白和Sp1蛋白阳性情况,分析PI3K和NF-κB p65蛋白表达与宫颈癌临床病理参数的相关性。结果宫颈癌组织中PI3K、NF-κB p65蛋白阳性表达率为62.90%和69.35%,癌旁正常组织中无阳性表达,两组比较,P<0.05。不同年龄、病理分型、肿瘤直径患者的PI3K、NF-κB p65蛋白阳性表达比较,差异无统计学意义(P>0.05);FIGOⅢ~Ⅳ期患者PI3K和NF-κB p65阳性表达率为76.92%和82.05%,高于FIGOⅠ~Ⅱ期患者的39.13%和47.83%(P<0.05);不同分化程度患者PI3K和NF-κB p65阳性表达率从高到低依次为低分化(83.33%,94.44%)、中分化(61.11%,63.89%)、高分化(25.00%,37.5%)(P<0.05);淋巴结转移患者的PI3K和NF-κB p65阳性表达率分别为86.96%和95.65%,高于无淋巴结转移患者的48.72%和53.85%(P<0.05);相关性分析显示,宫颈癌患者的PI3K和NF-κB p65表达水平与FIGO分期、淋巴结转移呈正相关,与分化程度呈负相关(P<0.05)。结论宫颈癌组织中PI3K、NF-κB p65蛋白阳性表达率均高于癌旁正常组织,并与FIGO分期、淋巴结转移呈正相关,与分化程度呈负相关,对于宫颈癌诊治具有一定的临床意义。

酵母双杂交系统的原理及应用

0引言 蛋白质和蛋白质的相互作用是很多生命现象的基础.随着分子生物学技术的发展,特别是人类基因组计划的完成,使人类对基因的结构和功能的认识不断加深,但基因编码的蛋白质的功能研究尚是一个难题.酵母双杂交(yeast two hybrid)技术是利用酵母遗传学方法分析蛋白质之间的相互作用,该方法建立以来,经过不断的完善和发展,不但可以检测已知蛋白质之间的相互作用,更重要的在于发现新的与已知蛋白相互作用的未知蛋白.

Pim-3与NF-κB在乳腺浸润性导管癌中的表达及相关性研究

目的探讨Pim-3与NF-κB在乳腺浸润性导管癌发病中的作用。方法用免疫组织化学技术SP法,检测Pim-3与NF-κB在75例乳腺浸润性导管癌、21例乳腺导管内癌及30例正常乳腺组织中的表达,分析它们与乳腺癌临床病理因素的关系及两者的相关性。结果在乳腺浸润性导管癌中Pim-3的阳性表达率为77.3%、NF-κB为68.0%,在乳腺导管内癌中Pim-3的阳性表达率为52.4%、NF-κB为42.9%,在正常乳腺组织中Pim-3的阳性表达率为23.3%、NF-κB为16.7%。Pim-3阳性表达率与肿瘤直径、组织学分级、临床病理分期,NF-κB阳性表达率与肿瘤直径、组织学分级、淋巴结转移有相关性。Spearmen秩相关分析,乳腺癌中Pim-3的阳性表达与NF-κB阳性表达呈正相关(r=0.243)。结论 Pim-3与NF-κB在乳腺癌的发生、发展中具有重要的促进作用,其阳性表达对预后的判断具参考作用。

基因新成果面面观

纷繁的医学研究的进展让人眼花缭乱，稍加整理，猛然发现2006年相当多的研究似乎都瞄向了同一个方向：基因!

Termination of DNA Replication and the Role of Enzymes in Recombination

DNA is the genetic material of all cells, containing coded information about cellular molecules and processes. DNA consists of two polynucleofide strands twisted around each other in a double helix. The first step in cellular division is to replicate DNA so that copies can be distributed to daughter cells. Additionally, DNA is involved in transcribing proteins that direct cell growth and activities. However, DNA is tightly packed into genes and chromosomes. In order for replication or transcription to take place, DNA must firstly unpack itself so that it can interact with enzymes. DNA packing can be visualized as two very long strands that have been intertwined millions of times, tied into knots, and subjected to successive coiling. However, replication and transcription are much easier to accomplish if the DNA is neatly arranged rather than tangled up in knots. Enzymes are essential to unpacking DNA. Enzymes act to slice through individual knots and reconnect strands in a more orderly way. Hypothesizing that Termination of DNA replication proteins gave rise to those of eukaryotes during evolution, we chose the DNA polymerase （which infects microalgae） as the basis of this analysis, as it represents a primitive recombination. We show that it has significant similarity with replicative DNA polymerases of eukaryotes and certain of their large DNA. Sequence alignment confirms this similarity and establishes the presence of highly conserved domains in the polymerase amino terminus. Subsequent reconstruction of a phylogenetic tree indicates that these algal DNA are near the root of the containing all recombination. DNA polymerase delta members but that this does not contain the polymerases of other DNA. We consider arguments for the polarity of this relationship and present the hypothesis that the replication genes of DNA. DNA can be visualized as a complicated knot that must be unknotted by enzymes in order for replication or transcription to occur. It is perhaps not surprising then that connections between mathematical knot theory and biology have been discovered. By thinking of DNA as a knot, we can use knot theory to estimate how hard DNA is to unknot. This can help us estimate properties of the enzymes that unknot DNA.