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991.
Activation or suppression of intracellular signaling via the mitogen-activated protein kinase (MAPK) family has been linked to expression of matrix metalloproteinases (MMP) in experimental models, but this association has not been demonstrated in clinical material. The objective of this study was to investigate the possible association between expression and activity of MMP, expression of the MMP inducer EMMPRIN, and the expression (level) and phosphorylation status (activity) of the extracellular-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK) and high osmolarity glycerol response kinase (p38) in effusions from patients diagnosed with serous ovarian carcinoma. MAPK level and activity were studied in 55 effusions using immunoblotting. MMP-1, MMP-2, MMP-9 and EMMPRIN expression was studied using immunocytochemistry (ICC) and mRNA in situ hybridization (ISH). The gelatinolytic activity of MMP-2 and MMP-9 was measured by zymography. ERK and phospho-ERK (p-ERK) were detected in 54/55 (98%) and 50/55 (91%) specimens, respectively. JNK and p-JNK were detected in 53/55 (96%) and 38/55 (69%) specimens, respectively. p38 was expressed in 54/55 (98%) specimens, and its phosphorylated form was found in 51/55 (92%). MMP-2 mRNA expression (P=0.048), protein expression (P=0.046) and gelatinolytic activity (P=0.039) correlated with ERK phosphorylative activity. MMP-2 activity also correlated with p38 activity (P=0.017). MMP-9 protein expression correlated with phosphorylation of p38 (P=0.046), but enzyme activity showed inverse relationship with both p-ERK (P=0.05) and p-p38 (P=0.033) expression. EMMPRIN expression correlated with MMP-1 (P<0.001), MMP-2 (P=0.042) and MMP-9 (P=0.029) expression, as well as with ERK activity (P=0.001). Our results present the first evidence of a possible link between MAPK signaling and MMP expression and activity in vivo. These data may expand our understanding regarding the mechanisms by which MMP synthesis is regulated in effusions and possibly affect treatment strategies for this form of malignancy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
992.
目的研究骨髓间充质干细胞(MSC)对脐带血(CB)CD34^+细胞体外增殖和造血重建能力的影响。方法取人骨髓单个核细胞贴壁培养.梭形细胞完全融合后传代,用流式细胞仪检测免疫表型;将CBCD34^+细胞接种到MSC或其他培养液中.比较不同培养条件对造血干细胞扩增能力、集落形成能力及黏附分子表达的影响。结果在加入IL-3的培养体系中.在MSC和细胞因子作用下,CD34^+细胞扩增7d和14d后,有核细胞(NC)、CD34^+细胞和CDl33^+细胞数,实验组均显著多于对照组。CD34+细胞在未加入IL-3的培养体系中培养8d后,实验组NC、CD34^+细胞、CD34^+CD38-细胞和造血祖细胞集落扩增倍数均显著高于对照组。扩增后CD34^+细胞的ALCAM、VLA-α4、VLA-α5、VLA-β1、HCAM、PECAM和LFA-1表达较扩增前无显著变化。结论MSC可为造血干细胞(HSC)体外扩增提供适宜的微环境,有助于CD34^+细胞体外增殖并抑制HSC分化,保持其造血重建潜能和归巢能力。  相似文献   
993.
Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a newly introduced category of the revised World Health Organization classification. We reported a case of cervical LCNEC with cytogenetic analysis by comparative genomic hybridization (CGH). The cervical tumor showed moderately increased mitotic activity (8-14 mitotic figures per 10 high-power fields) and focal necrosis, which made it problematic to differentiate from atypical carcinoid. CGH analysis failed to detect chromosome 11q loss that has been reported to be characteristic of pulmonary atypical carcinoids. Furthermore, chromosome 3q amplification, which has been detected frequently in pulmonary small cell carcinomas and LCNECs but not in pulmonary typical and atypical carcinoids, was the most remarkable chromosomal aberration. Although CGH reports are extremely rare in neuroendocrine tumors of the uterine cervix, specific chromosomal aberrations may be useful in their distinction.  相似文献   
994.
肾细胞癌中抑癌基因PTEN的表达及生物学意义   总被引:2,自引:3,他引:2  
目的 :研究抑癌基因PTEN在肾细胞癌的表达及其生物学意义。方法 :应用免疫组织化学S P法检测 5例正常肾组织、18例癌旁肾组织和 40例肾细胞癌组织中抑癌基因PTEN的表达。结果 :5例正常肾组织和 18例癌旁肾组织均有较强的PTEN蛋白的表达 ,二者PTEN蛋白的表达强度、阳性细胞的分布形式无差异。抑癌基因PTEN在肾细胞癌中的表达不同于正常肾组织和癌旁肾组织 ,12 5 %的肾细胞癌呈PTEN蛋白阴性 ;17 5 %的肾细胞癌PTEN蛋白呈弱阳性 ;70 %的肾细胞癌PTEN蛋白呈阳性或强阳性 ,与癌旁组织PTEN蛋白的染色强度无差异。PTEN蛋白阴性的肾细胞癌 ,肾门淋巴结转移率为80 % ;PTEN蛋白阳性的肾细胞癌 ,肾门淋巴结转移率为 2 0 %。PTEN蛋白阴性肾细胞癌的肾门淋巴结转移率与PTEN阳性肾细胞癌的肾门淋巴结转移率比较 ,差异有显著性 (P <0 0 5 )。结论 :肾细胞癌中存在着抑癌基因PTEN的表达缺失和异常 ;抑癌基因PTEN的表达异常可能与肾细胞癌的发生、发展有关 ,抑癌基因PTEN是肾细胞癌的一种新的相关基因。  相似文献   
995.
目的 建立HCV核心蛋白细胞表达模型,并探讨其对细胞端粒酶活性的影响。方法 用PCR法扩增出HCV核心基因cDNA,将其插入真核表达载体pBK-CMV的HindⅢ和BamHⅠ位点间,构建重组质粒pBK-HCVc。再将重组质粒pBK-HCVc和空载体分别导入肝癌细胞株HepG2中,G418筛选,RT-PCR、免疫组化和蛋白印迹鉴定HCV核心蛋白表达。PCR-ELISA法检测端粒酶活性。结果 构建的pBK-HCVc质粒在HepG2细胞中有稳定表达。表达HCV核心蛋白的细胞HepG2-C的端粒酶活性较转染空载体的细胞HepG2-CMV明显升高。结论 HCV核心蛋白上调了端粒酶活性,可能是HCV诱发肝细胞癌的一种途径。  相似文献   
996.
Merkel cell carcinoma was diagnosed in a 79-year-old Caucasian woman. The tumour was localised to the upper lip and was in stage T2. After successful cryosurgery and a 7-year tumour-free period, a new tumour developed in her palatine tonsil. Histologically and immunohistochemically, this resembled the tumour in the lip. The regional lymph nodes were devoid of metastasis. The paraffin-embedded material of the two tumours and the unaffected lymphatic tissue were analysed with DNA microarrays for comparative genomic hybridisation to assess the genetic relationship of the tumours. In both tumours, regions on 2p and 10p were commonly over-represented, while 41 regions on chromosomes 1–4, 6, 8–9, 11 and 14–22 were commonly under-represented. Chromosomes 1, 3, 4, 16–18 and X were most frequently involved in the DNA losses. In gene copy numbers in the two tumours, 31 chromosome locations were found to be differently affected. The partly similar and partly different molecular patterns indicated a genetic relationship between the tumours and excluded the possibility that the tonsillar tumour was a metastasis. The findings suggest that a genetically altered field was the reason for the development of the tonsillar cancer; thus, it can be regarded pathogenetically as a second field tumour.  相似文献   
997.
目的 通过检测胃癌细胞系SGC7901/VCR、SCC7901和BGC-823,以及永生化胃上皮细胞系GES中B7-H1的表达,探讨B7-H1与胃癌的发生及多药耐药(MDR)的关系.方法 上述细胞系培养于含10%灭活胎牛血清的RPMI-1640培养基中,利用RT-PCR技术、细胞免疫化学染色以及细胞免疫荧光染色技术与流式细胞术检测4种细胞系中B7-H1 mRNA与B7-H1蛋白的表达情况,并比较其在4种细胞系中的表达强度.结果 B7-H1 mRNA在4种细胞系中均有表达,表达强度按照GES-1、BGC-823、SGC-7901、SGC-7901/VCR的顺序递增;细胞免疫化学染色与免疫荧光染色表明,B7-H1蛋白主要表达在上述细胞的细胞膜和少量细胞浆中.结合流式细胞术检测进一步证实,B7-H1蛋白在4种细胞系中的表达结果与mRNA的表达一致.结论 B7-H1表达在胃上皮细胞上,可能通过抑制机体免疫反应,促进胃癌细胞生长及MDR基因表达.  相似文献   
998.
从人肝癌组织中提取总RNA,RT—PCR合成hTIMP-1的全长cDNA,克隆到腺病毒载体AdEasy系统的穿梭质粒pAdTraek—CMV上,与骨架质粒pAdEasy-1在BJ5183受体菌中进行同源重组,成功构建含hTIMP-1全长eDNA的重组腺病毒载体,经293细胞的包装、扩增,生成含hTIMP-1基因的重组腺病毒AdhTIMP-1并实现体外表达,为进一步研究肝癌浸润和转移机理以及肝癌的基因治疗提供实验基础。  相似文献   
999.
Most models suggest that the cell of origin of papillary carcinoma is the mature thyroid follicular epithelial cell. In a recent study, p63 was detected in papillary carcinoma, Hashimoto's thyroiditis, and in squamoid aggregates and solid cell nests (SCNs), embryonic remnants found sporadically in the fully developed thyroid. In the present study, the relationship between solid cell nests and papillary carcinoma was investigated further. Four-micrometer sections from 88 routinely fixed and processed archival thyroidectomy specimens were pretreated with citric acid pH 6.0 for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained with a streptavidin-biotin kit and diaminobenzidine as chromogen and were counterstained with hematoxylin. Squamoid aggregates or SCNs were noted in 21 specimens. Several morphologic variants of SCNs were found, all of which displayed p63 positivity. These included undifferentiated SCNs and those displaying commitment toward squamoid and ciliated glandular differentiation. Small, morphologically inconspicuous aggregates of p63-positive cells were commonly found in Hashimoto's thyroiditis. Commitment of p63-positive undifferentiated cells toward thyroid follicular epithelial differentiation was occasionally noted. One SCN variant, also associated with Hashimoto's thyroiditis, was a floretlike arrangement of p63-positive cells with fusiform nuclei. p63 staining was strong and uniform in some SCNs, but in other SCNs it was compartmentalized and homologous to stem cell-staining patterns in normal squamous or bronchial epithelia. Stem cell-like staining, associated with compartmentalized p63 staining or p63-positive undifferentiated cells, was noted in 7 of 27 papillary carcinomas. p63 immunostaining is a highly sensitive means of detecting SCNs. p63 expression patterns in SCNs and a subset of papillary carcinomas are closely homologous to stem cell-associated p63 staining patterns that have been described elsewhere in squamous and bronchial epithelia. We propose a stem-cell-associated model of papillary carcinoma oncogenesis that suggests that (1) p63-positive embryonal remnants rather than mature follicular cells are the cells of origin of a subset of papillary carcinomas; (2) these p63-positive cells are pluripotent and may stay undifferentiated or undergo benign squamoid or glandular maturation, may undergo thyroid follicular epithelial differentiation, may undergo oncogenic change leading to papillary carcinoma, or may trigger an immune reaction, resulting in lymphoid infiltration and Hashimoto's thyroiditis; and (3) Hashimoto's thyroiditis and papillary carcinoma may therefore be linked etiologically, because both disorders may be initiated by the same population of pluripotent p63-positive embryonal stem cell remnants.  相似文献   
1000.
Genome-wide profiling of oral squamous cell carcinoma   总被引:7,自引:0,他引:7  
Oral squamous cell carcinoma (OSCC) is a common malignancy, the incidence of which is particularly high in some Asian countries due to the geographically linked areca quid (AQ) chewing habit. In this study, array-based comparative genomic hybridization was used to screen microdissected OSCCs for genome-wide alterations. The highest frequencies of gene gain were detected for TP63, Serpine1, FGF4/FGF3, c-Myc and DMD. The highest frequencies of deletion were detected for Caspase8 and MTAP. Gained genes, classified by hierarchical clustering, were mainly on 17q21-tel; 20q; 11q13; 3q27-29 and the X chromosome. Among these, gains of EGFR at 7p, FGF4/FGF3, CCND1 and EMS1 at 11q13, and AIB1 at 20q were significantly associated with lymph node metastasis. The genomic profiles of FHIT and EXT1 in AQ-associated and non-AQ-associated OSCCs exhibited the most prominent differences. RT-PCR confirmed the significant increase of TP63 and Serpine1 mRNA expression in OSCC relative to non-malignant matched tissue. A significant increase in Serpine1 immunoreactivity was observed from non-malignant matched tissue to OSCC. However, there was no correlation between the frequent genomic loss of Caspase 8 and a significant decrease in Caspase8 expression. These data demonstrate that genomic profiling can be useful in analysing pathogenetic events involved in the genesis or progression of OSCC.  相似文献   
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