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991.
Soonmyoung Paik M.D. 《Breast cancer research and treatment》1992,22(1):31-38
Summary Expression of IGF-I and IGF-II was studied in human breast cancer tissues by in situ hybridization. IGF-I mRNA was detected only in stromal cells adjacent to normal breast epithelial cells. Stromal cells associated with the tumor cells did not contain IGF-I, nor did malignant or benign breast epithelial cells. In contrast, IGF-II mRNA was found in both the malignant epithelial cells and their adjacent stromal cells. These data imply that stromal cells associated with breast epithelium may switch expression from IGF-I to IGF-II during breast cancer evolution. This appearance of IGF-II expression may identify cancer-associated stromal cells that have a fetal phenotype. 相似文献
992.
Luis H. Ramirez Morbize Juliéron Marc Bonnay Serge Koscielny Zhongxin Zhao Alain Gouyette Jean-Nicolas Munck 《Investigational new drugs》1995,13(1):51-53
Suramin is an antitrypanosomal compound with confirmed efficacy against several human malignancies. It is generally assumed
that its mechanism of action includes the interaction with different growth factors, unlike most of the anticancer drugs.
Its anticancer activity has not been testedin vivo against squamous cell carcinoma. The purpose of this study was to assess the efficacy and toxicity of suraminin vivo andin vitro on the VX2 tumor model at therapeutic monitored plasma concentrations. We determined the pharmacokinetics of suramin in rabbits,
and modelized its administration in order to obtain plasma concentrations between 150 and 300 μg/ml throughout the treatment
course of 3 weeks. Under these conditions, antitumor effects of suramin were evaluatedin vivo by comparing liver tumor involvement in suramin-treated and control rabbits. Liver involvement was quantified by image analysis
andin vitro effects were also determined at the same concentrations.In vivo, suramin promoted liver tumor growth significantly (p<0.05), compared to untreated controls.In vitro, suramin significantly stimulated tumor cell growth at concentrations above 200 μg/ml (p<0.01). Suramin may have stimulatory
effects on tumor growth in squamous cell carcinoma at relevant plasma drug concentrations. Caution should be taken in further
trials in patients with squamous cell carcinomas. 相似文献
993.
指骨内原发性腱鞘巨细胞瘤四例报告 总被引:3,自引:1,他引:2
指骨原发性骨内腱鞘巨细胞瘤较罕见,本院曾收治4例,作一报道。其临床特征是患指指骨增粗,有隐痛感.X线片显示指骨皮质骨膨胀性变而,极似指骨内生软骨瘤。组织学特征是组织细胞性基质细胞增殖,胞浆里网状空泡样改变,并有散在的多核巨细胞存在。诊断时需与骨巨细胞瘤相鉴别.4例均行病灶刮除加酒精灭活植骨治疗,术后随访平均13个月.功能恢复良好.未见复发.指骨内原发性腱鞘巨细胞瘤主要诊断依据必须结合病理改变及X线片表现,才能和其他有关肿瘤相鉴别. 相似文献
994.
端粒酶是一种RNA依赖的逆转录酶 ,能够延长染色体末端的端粒长度。它由三个主要部分组成———端粒酶RNA亚单位、端粒酶催化亚单位及连接二者的端粒酶相关蛋白。端粒酶激活是细胞永生化和肿瘤形成的关键步骤 ,其活性受到多种因素的调控。端粒酶催化亚单位hTERTmRNA可能是其激活的关键限速步骤。在妇科肿瘤的癌变过程中 ,端粒酶活性不同程度地升高 ,hTERT不断上调。端粒酶及其催化亚单位有可能成为妇科肿瘤筛查的一种重要的肿瘤标志物 相似文献
995.
Carcinoid tumors and inflammatory bowel disease. 总被引:2,自引:0,他引:2
Three cases are described in which carcinoid tumors arose in previously established inflammatory bowel disease: two were in the ileum in cases of Crohn's disease, and one was in the rectum in a case of ulcerative colitis. Review of this association in the literature suggests that it may be more than fortuitous. 相似文献
996.
生长抑素受体亚型在人鼻咽癌细胞株CNE2中表达 总被引:3,自引:0,他引:3
背景与目的:生长抑素受体(somatostatin receptor SSTR)在许多肿瘤组织均有表达,为生长抑素类似物如奥曲肽用于这些肿瘤的治疗提供了生物学基础,但对生长抑素受体在鼻咽癌中表达情况的研究甚少。本研究旨在了解生长抑素受体基因在鼻咽癌细胞中的表达情况,为生长抑素类似物用于鼻咽癌治疗的进一步研究提供试验基础。方法:采用RT—PCR法和SP免疫组化法联合检测体外培养的人鼻咽癌细胞株CNE2的SSTRs表达,并对PCR mRNA产物测序以鉴定结果。结果:RT—PCR提示人鼻咽癌细胞株CNE2分别表达生长抑素受体亚型SSTR1、SSTR2、SSTR4;免疫组化结果:人鼻咽癌细胞株CNE2表达SSTR1、SSTR2A为强阳性(〉60%),表达SSTR4为弱阳性、SSTR2介于两者之间、SSTR3和SSTR5则无表达。结论:我们的研究证实人鼻咽癌细胞株CNE2有多种生长抑素受体亚型基因表达,且以表达SSTR1、SSTR2较多。 相似文献
997.
B. Ruiter V. Trégoat L. M''Rabet J. Garssen C. A. F. M. Bruijnzeel-Koomen E. F. Knol E. van Hoffen 《Clinical and experimental allergy》2006,36(3):303-310
BACKGROUND: One to two percent of infants suffer from IgE-mediated allergic reactions against cow's milk proteins. Most children develop clinical tolerance, but approximately 15% are still allergic by the age of 10 years. Little is known about the T cell epitopes in individual cow's milk protein in relation to allergy and tolerance. OBJECTIVE: To identify T cell epitopes in alphas1-casein, the most abundant milk protein, and to investigate T cell responses toward these epitopes in allergic, atopic and non-atopic children. METHODS: Allergen-specific T cell lines (TCLs) were derived from peripheral blood mononuclear cells of 11 cow's milk allergic, nine atopic and nine non-atopic children. T cell responses were measured to alphas1-casein and to overlapping peptides (18-mers), spanning the alphas1-casein molecule. Proliferation was determined by incorporation of (3)H-thymidine, and cytokine production (IL-10, IL-13 and IFN-gamma) was measured by ELISA. RESULTS: Four main regions (amino acid (AA) residues 43-66, 73-96, 91-114 and 127-180) in the alphas1-casein molecule were immunogenic to T cells, among which the AA residues 133-156 spanned the immunodominant part. Only subtle differences were found in peptide recognition between the subject groups. Some of the peptides induced slightly Th1- or Th2-skewed cytokine responses. The increased levels of IL-10 in response to alphas1-casein observed in TCLs from atopic children appeared not to be linked to recognition of specific IL-10-inducing epitopes. CONCLUSIONS: The immunodominant sequence in alphas1-casein is spanned by AA residues 133-156. Tolerance towards alphas1-casein in atopic children may be mediated by an overall induction of IL-10 and not by recognition of certain T cell epitopes. The identified T cell epitopes in children with cow's milk allergy may be useful targets in developing peptide immunotherapy. 相似文献
998.
The knee meniscus exhibits extensive spatial variations in native healing capacity, biochemical composition, and cell morphology that suggest the existence of distinct phenotypes for meniscus cells. Constitutive gene expression levels of appropriate extracellular matrix proteins may serve as useful molecular markers of cellular phenotypes; however, relatively little is known of variations in the gene expression for meniscus cells of different regions of the tissue. The objective of the present study was to evaluate constitutive differences between radial inner and outer regions in gene expression for extracellular matrix proteins relevant to the meniscus. A secondary objective was to determine if these region-specific differences in gene expression are maintained after periods of monolayer culture. The innermost regions of the meniscus were found to constitutively express higher mRNA levels for proteins highly expressed in articular cartilage, including aggrecan, type II collagen, and NOS2. In contrast, the outer meniscus was found to contain higher gene expression for proteins associated with fibrous tissues including type I collagen, and the proteases MMP2 and MMP3. Isolated inner and outer meniscus cells maintained these region-specific gene expression patterns for collagens and proteoglycans during short-term monolayer culture. The results provide new information that suggests the utility of constitutive gene expression levels as molecular markers to distinguish tissue and cells of the inner and outer meniscus. 相似文献
999.
Shinya Kodashima Mitsuhiro Fujishiro Naohisa Yahagi Naomi Kakushima Masanori Nakamura Masao Omata 《Digestive endoscopy》2006,18(2):151-153
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors. 相似文献
1000.
目的 构建含有NT4和HA2-TAT的分泌型VP3真核表达载体,并观察其表达对人肝癌细胞HepG2和小鼠成纤维细胞NIH3T3的影响.方法 构建了含鸡贫血病毒VP3基因和NT4、HA2-TAT基因的分泌型真核表达载体--NT4-Apoptin-HA2-TAT重组腺相关病毒载体.体外转染人肝癌细胞HepG2和小鼠成纤维细胞NIH3T3,用MTT法和流式细胞学,检测凋亡素融合基因诱导细胞凋亡的效果.结果 携带融合基因的重组腺相关病毒感染人肝癌HepG2细胞48 h后,显示了很强的诱导肿瘤细胞凋亡的能力.而对小鼠成纤维细胞NIH3T3细胞无明显凋亡作用.结论 分泌型NT4-Apoptin-HA2-TAT重组腺相关病毒载体转染细胞后能够被正常分泌、穿膜并特异性诱导肿瘤细胞凋亡,为肿瘤的基因治疗提供了新的思路. 相似文献