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1.
The mid‐distal region of mouse chromosome 4 (Chr 4) is homologous with human Chr 1p36. Previously, we reported that mouse Chr 4 carries a quantitative trait locus (QTL) with strong regulatory effect on volumetric bone mineral density (vBMD). The intent of this study is to utilize nested congenic strains to decompose the genetic complexity of this gene‐rich region. Adult females and males from 18 nested congenic strains carrying discrete C3H sequences were phenotyped for femoral mineral and volume by pQCT and for trabecular bone volume (BV), tissue volume (TV), trabecular number (Trab.no), and trabecular thickness (Trab.thk) by MicroCT 40. Our data show that the mouse Chr 4 region consists of at least 10 regulatory QTL regions that affected either or both pQCT and MicroCT 40 phenotypes. The pQCT phenotypes were typically similar between sexes, whereas the MicroCT 40 phenotypes were divergent. Individual congenic strains contained one to seven QTL regions. These regions conferred large positive or negative effects in some congenic strains, depending on the particular bone phenotype. The QTL regions II to X are syntenic with human 1p36, containing from 1 to 102 known genes. We identified 13 candidate genes that can be linked to bone within these regions. Six of these genes were linked to osteoblasts, three linked to osteoclasts, and two linked to skeletal development. Three of these genes have been identified in Genome Wide Association Studies (GWAS) linked to 1p36. In region III, there is only one gene, Lck, which conferred negative pQCT and MicroCT 40 phenotypes in both sexes. This gene is important to development and functioning of T cells, has been associated with osteoclast activity, and represents a novel bone regulatory gene that merits further experimental evaluation. In summary, congenic strains are powerful tools for identifying regulatory regions that influence bone biology and offer models for testing hypotheses about gene‐gene and gene‐environment interactions that are not available to experimental work in humans. © 2012 American Society for Bone and Mineral Research  相似文献   
2.
目的 探讨癌基因、抑癌基因在HBV相关HCC中的表达。方法 提取 2 2例HBV相关HCC患者肝癌及癌旁组织的mRNA,逆转录合成含有 3 3p dATP标记的cDNA探针,与含有 3 1 7 0个基因或表达序列标签 (EST)的cDNA微阵列进行杂交,图像分析,基因数据库搜索,RT PCR验证。结果  肝癌组织与癌旁组织间共有 1 3 6 9个差异表达基因或表达序列标签 (EST),其中有 1 2 1个基因或EST表达差异 > 2倍。肝癌组织与癌旁组织比较, 1 2 1个基因或EST中表达上调的有 8 8个,表达下调的有 3 3个。TM4SF1 基因在肝癌组织中阳性表达率为 8 6. 4% , 在癌旁组织中无表达 (P <0. 001 );ST1 4基因在癌旁组织中阳性表达率为 7 2. 8% ,在癌组织中无表达 (P < 0. 0 1 )。结论 TM4SF1基因的表达上调和ST1 4基因的表达下调参与了肝癌的发生。  相似文献   
3.
目的 研究多药耐药相关蛋白基因 (MRP)和肺耐药蛋白基因 (LRP)在肝细胞癌 (HCC)中的表达及其与临床的关系。方法 采用SP免疫组化和PCR技术检测 5 4例HCC和 2 4例癌旁组织及 1 2 例肝炎后肝硬化组织中的两种基因表达。结果 MRP和LRP在 3种组织中均有表达,HCC组织中其基因表达显著高于其他组织 (P< 0. 0 5 )。HCC中两种基因表达呈正相关 (r= 0. 3 1 2, P <0. 0 5; r= 0. 3 2 8, P< 0. 0 5 );其表达与HCC的分化程度有关 (P< 0. 0 5 )。并且其表达阳性组患者化疗后AFP有效率和平均生存期分别高于和长于阴性组 (P< 0. 0 5 ),但LRP与平均生存期无关 (P> 0. 0 5 )。结论 HCC多药耐药 (MDR)与两种基因表达有关,起源于内源性耐药;检测其表达对预测化疗耐药具有指导意义;MRP可能与预后有关。  相似文献   
4.
MRP1/CD9蛋白在人肝细胞癌中的表达及其意义   总被引:1,自引:0,他引:1  
目的 探讨MRP1 /CD9蛋白在人肝细胞癌 (HCC)中的表达及其与癌侵袭转移的关系。方法 构建肝癌组织芯片。样本包括肝细胞癌及癌旁肝组织 1 5 2例,癌栓 2 2例,肝内转移癌 4例,肝外转移癌 1 7例。正常对照肝组织 5例。应用免疫组织化学 (免疫组化 )方法检测肝癌组织芯片中样本MRP1 /CD9蛋白的表达。结果  2 7% ( 4 1 /1 5 2 )肝细胞癌原发灶表达MRP1 /CD9蛋白。伴癌栓形成HCC中MRP1 /CD9蛋白表达率低于无癌栓形成者 (分别为 2 1. 8 2%和 4 0. 4 8% ; P < 0. 0 5 )。巨块型肝癌中MRP1 /CD9 蛋白表达率亦低于直径在 1 0cm以下者 (分别为 5%和 3 4. 8 2% ; P <0. 01 )。MRP1 /CD9蛋白表达尚与HCC病理分级及血清AFP水平有关:病理分级 2级的阳性表达率高于 3 ~ 4级 (分别为 3 9. 0 2%和 2 2. 5 2% ; P = 0. 0 4 3 ),血清AFP≤ 2 0μg/L者阳性表达率高于 >2 0μg/L者 (分别为 4 1. 9 4%和 2 2. 5 0% ; P = 0. 0 2 9 )。结论 肝细胞癌MRP1 /CD9蛋白表达水平低下可能与癌组织侵袭转移有关。  相似文献   
5.
6.
胃癌癌前病变中医证候与凋亡相关癌基因mRNA表达的关系   总被引:4,自引:1,他引:3  
【目的】 探讨胃癌癌前病变(PLGC)中医证候与bcl-2癌基因和p53抑癌基因mRNA表达的关系。【方法】经胃镜及病理证实为PLGC病例共40例,其中中度异型增生24例,重度异型增生9例,不完全性结肠化生7例;兼气滞证10例,兼胃热证12例,兼血瘀证18例。采用原位分子杂交的方法检测胃粘膜活检标本bcl-2癌基因和p53抑癌基因mRNA表达。【结果】本组PLGC中,bcl-2癌基因和p53抑癌基因在转录水平均有过度表达,并随病变的进展而表达逐渐增高。在不同的兼证中,bcl-2癌基因和p53抑癌基因mRNA的表达强度依次为兼气滞证<兼胃热证<兼血瘀证。【结论】bcl-2癌基因和p53抑癌基因在PLGC中有异常表达,其表达与不同兼证有关且可能有一定的证候特异性。  相似文献   
7.
原发性肝癌患者原发灶和转移灶中p16状态的比较   总被引:1,自引:0,他引:1  
目的 探讨p16基因在原发性肝癌发生、转移过程中的动态变化。方法 收集 18例患者原发性肝癌原发灶及远处转移灶石蜡标本 3 6块 ,以PCR SSCP方法检测p16基因exon 2。结果  18例中p16变异占 2 2 .2 % (4 /18) ,其中 2例仅在转移灶发现 ,另 2例为原发灶和转移灶均发生变异 ,ex on 2缺失占 11.1% (2 /18) ,突变占 11.1% (2 /18) ,但该 4例变异均发生在 7例原发性肝癌转移同时伴有复发的患者 (5 7.1% ,4/7) ,显著高于仅转移无复发患者 (0 /11) (P <0 .0 5 )。 4例p16变异病例的术后复发转移时间 (7个月 )显著早于 14例无变异者 (2 1个月 ) (P <0 .0 5 )。结论 在原发性肝癌的复发转移过程中 ,p16变异起重要作用 ;小部分p16变异也可始发于转移灶。  相似文献   
8.
目的 研究外源性p2 7KIP1 基因对人胃癌细胞SGC790 1的生物学效应。方法 采用脂质体转染法将p2 7KIP1 全长cDNA转入胃癌细胞系SGC790 1中 ,通过免疫印迹分析以及RNA斑点杂交方法检测 p2 7KIP1 基因在蛋白质和mRNA水平的表达 ;用细胞活力实验显示转染 p2 7KIP1 基因对细胞增殖的作用 ;用裸鼠成瘤实验观察外源性 p2 7KIP1 基因对人胃癌细胞SGC790 1的体外生物学效应。结果 转染p2 7KIP1 的SGC790 1细胞在mRNA和蛋白质水平均有高水平p2 7KIP1 的表达。细胞活力检测显示在外加Zn2 +48h后细胞生长被抑制 42 % ;转染p2 7KIP1 的SGC790 1细胞在裸鼠体内的成瘤能力明显下降 (P <0 .0 1 )。结论 外源性p2 7KIP1 基因能抑制人胃癌细胞SGC790 1的生长及成瘤能力。  相似文献   
9.
Despite significant advances in our understanding of copper efflux mechanisms since the discovery and characterization of Cu-ATPase genes mutated in Menkes and Wilson diseases, little is known about how cells acquire this essential micronutrient. Recent studies on Ctr1 have illuminated how copper may be transported into mammalian cells.  相似文献   
10.
The distal end of mouse chromosome 1 (Chr 1) harbors quantitative trait loci (QTLs) that regulate bone mineral density (BMD) and share conserved synteny with human chromosome 1q. The objective of this article was to map this mouse distal Chr 1 region and identify gene(s) responsible for BMD regulation in females. We used X‐ray densitometry [ie, dual‐energy X‐ray Absorptiometry (DXA), micro–computed tomography (µCT), and peripheral quantitative computed tomography (pQCT)] to phenotype a set of nested congenic strains constructed from C57BL/6BmJ (B6/Bm) and C3H/HeJ (C3H) mice to map the region associated with the BMD QTL. The critical region has been reduced to an interval of 0.152 Mb that contributes to increased BMD when C3H alleles are present. Histomorphometry and osteoblast cultures indicated that increased osteoblast activity was associated with increased BMD in mouse strains with C3H alleles in this critical region. This region contains two genes, Aim2, which binds with cytoplasmic dsDNA and results in apoptosis, and AC084073.22, a predicted gene of unknown function. Ovariectomy induced bone loss in the B6/Bm progenitor and the three congenic strains regardless of the alleles present in the critical BMD region. High dietary fat treatment (thought to suppress distal Chr 1 QTL for BMD in mice) did not induce bone loss in the congenics carrying C3H alleles in the critical 0.152 Mb carrying the AIM2 and AC084073.22 genes. Gene expression studies in whole bone of key congenics showed differential expression of AC084073.22 for strains carrying B6/Bm versus C3H alleles but not for Aim2. In conclusion, our data suggest that osteoblasts are the cellular target of gene action and that AC084073.22 is the best candidate for female BMD regulation in the distal region of mouse Chr 1. © 2011 American Society for Bone and Mineral Research.  相似文献   
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