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81.
82.
Cell-cell adhesion molecules and signaling intermediates and their role in the invasive potential of prostate cancer cells 总被引:1,自引:0,他引:1
PURPOSE: The highly variable natural history of prostate carcinoma may be reflected in heterogeneity of invasive potential between tumors. MATERIALS AND METHODS: We have examined two prostate cancer cell lines of low invasive potential (CAHPV10 and PZHPV7) and three cell lines of high invasive potential (DU-145, PC-3, LNCapFGC), to determine whether specific adhesion molecule profiles correlated with their invasive behavior. RESULTS: Using an in vitro invasion assay, we demonstrated that DU-145, LNCapFGC and PC-3 cells were highly invasive compared with CA-HPV-10 and PZ-HPV-7 cells. LNCapFGC cells expressed high levels of E-cadherin, alpha-, beta- and gamma-catenin, desmoglein, desmoplakin and GSK3beta using immunoblotting. This was, in general, comparable to immunohistochemical staining. PC-3 cells had no E-cadherin or alpha-catenin, but expressed a high level of the HGF/SF receptor c-Met. In contrast, DU-145 cells were found to express E-cadherin and low levels for all other protein molecules, except c-Met. The DU-145 cell line also lacked alpha-catenin expression. In CA-HPV-10 and PZ-HPV-7 cells, there was no detection of APC, PECAM-1, P-cadherin or Wnt-1. DU-145, LNCapFGC and PC-3 cells formed cell-cell aggregates, which were reduced by inclusion of anti-E-cadherin antibody and the motogen HGF/SF. CONCLUSION: These results show that prostate cancer cells exhibit a diverse expression of cell-cell adhesion molecules and their signaling intermediates. The expression of these adhesion molecules bears an important relationship with the invasive phenotype of these cells. 相似文献
83.
目的 探讨膜型基质金属蛋白酶 - 1(membranetype - 1matrixmetalloproteinase,MT1-MMP)在卵巢上皮癌组织中的表达及其与肿瘤生物学行为和预后的关系。方法 用免疫组化SP法检测 5 6例卵巢上皮癌组织、 15例卵巢良性肿瘤组织以及 10例正常卵巢组织中MT1-MMP蛋白的表达。结果 6 7 9%的卵巢上皮癌组织MT1-MMP表达阳性 ,卵巢良性肿瘤组织很少表达 (4/ 15 ) ,正常卵巢组织中几乎不表达 (1/ 10 ) ,差异有显著性 (P <0 0 1)。MT1-MMP的表达水平与临床分期、组织学分级以及淋巴结转移密切相关。在单因素生存分析中 ,MT1-MMP的表达与患者预后不良有关。但是 ,在多因素分析中 ,MT1-MMP的表达并不是一个相对独立的预后因素。结论 ①MT1-MMP在卵巢上皮癌中异常高表达 ;②MT1-MMP表达促进卵巢癌的侵袭和转移 ,可作为判断卵巢癌恶性表型的有用指标 ;③MT1-MMP的阳性表达与患者不良预后有关。 相似文献
84.
Apart from clinical stage and lymph node status, acknowledged to be among the most powerful predictors of outcome in cervical cancer, the determination of prognosis and thereby the need for adjuvant therapy in surgically treated patients currently relies on a variety of histopathologic factors. The role of many of these is controversial. This may be because histopathology is genuinely lacking in sensitivity for predicting tumor behavior in vivo. There is, however, wide variation in histopathologic definitions and criteria. This is probably the major reason for both the lack of reproducibility in the reporting of certain factors and in their diminished value in predicting behavior. Tumor type, grade, vascular invasion, pattern of invasion, and depth are all extremely important prognostic indicators when used individually or as a part of a scoring system. 相似文献
85.
入侵红火蚁对我国生态环境的威胁及防制措施 总被引:1,自引:0,他引:1
入侵红火蚁入侵我国之后,可能会给我国生态环境带来极大的危害。其不断蔓延有可能成为我国农业生态和人民财产健康的威胁。本文主要介绍了红火蚁在全球生物入侵的基本情况,根据东西半球生物类型逐渐趋同的原理,借鉴美国等国家的经验,分析了红火蚁对生态环境的威胁,以及红火蚁的防制措施等相关国内外的研究。 相似文献
86.
Immune cells contribute to systemic cross-talk between the embryo and mother during early pregnancy in cooperation with the endocrine system 总被引:1,自引:0,他引:1
Hiroshi Fujiwara 《Reproductive Medicine and Biology》2006,5(1):19-29
In early pregnancy, human chorionic gonadotropin (HCG) stimulates the corpus luteum to produce progesterone that in turn maintains human embryo implantation in the uterus. This inevitable communication through blood circulation can be called 'systemic cross-talk between the embryo and mother'. Despite considerable evidence suggesting that the human corpus luteum cannot be maintained by HCG alone, no other responsible soluble factors have been proposed. We found that peripheral blood mononuclear cells (PBMC) derived from pregnant women promoted progesterone production by human luteal cells and propose that both hormones and immune cells participate in this systemic cross-talk. This systemic cross-talk by immune cells is believed to operate in embryo implantation. Splenocytes derived from pregnant mice promoted endometrial differentiation and embryo implantation in vivo . Human PBMC derived from women early in pregnancy promoted invasion of murine embryos in vitro. In addition, recombinant HCG increased the effects of human PBMC on murine embryo invasion. Human chorionic gonadotropin also increased chemokine production by human PBMC through a lectin–glycan interaction, which is a primitive pathway in the immune system. Furthermore, chemokines were shown to induce human trophoblast invasion. These findings suggest that the immune system positively contributes to systemic cross-talk between the embryo and mother in cooperation with the endocrine system. (Reprod Med Biol 2006; 5 : 19–29) 相似文献
87.
目的:观察胰头后面的神经分布,探讨胰头癌沿神经浸润转移的解剖学基础,为临床上清除由于胰头癌神经浸润转移所致的残留癌以及胰源性疼痛止痛术等提供相关的应用解剖学资料。方法:运用大体解剖学方法观测了30具成人尸体胰头后面神经分支的来源和分布特征。结果:(1)胰头后面的神经分支主要来源于右腹腔神经节(27例)、腹腔丛右侧半(20例)和肝丛(16例),少数发自肠系膜上丛(14例)。(2)胰头后面神经分布形式以成丛型.即“胰头丛”占多数(24例),仅有6例为不成丛型。(3)“胰共丛”的位置较恒定,肾贴于胰头后面,邻接下腔静脉和左肾静脉的末段。胰头后面神经分支进入胰头后面腺体的部位以右上、下象限为主(分别有21例和26例),其次为左下象限(14例),而左上象限最少(3例)。结论:胰头后面的神经分布丰富,其来源和分布具有一定的规律性和特点,为胰头癌神经浸润转移和术后局部肿瘤复发提供了可能,也是导致中、晚期胰腺癌剧烈疼痛的形态学基础。 相似文献
88.
Prognostic factors in maxillary sinus and nasal cavity carcinoma 总被引:2,自引:0,他引:2
J.F. Carrillo A. Güemes M.C. Ramírez-Ortega L.F. Oate-Ocaa 《European journal of surgical oncology》2005,31(10):1206-1212
AIMS: The aim of the present study is to define prognostic factors, particularly the impact of treatment on paranasal sinus and nasal cavity malignancies. MATERIAL AND METHODS: Retrospective study of patients with maxillary antrum and nasal fossae malignancies. A maxillectomy classification as performed to treat malignancies in our institution is described. Multivariate analysis of prognostic factors was done using the Cox's model. RESULTS: One hundred and nine patients were evaluated. Squamous cell carcinoma was found in 62 cases and in 95 patients the epicentre of the tumour was located in the maxillary antrum. Ten patients were treated with surgery only, 39 patients with surgery and adjuvant radiation therapy, 37 cases received only radiotherapy, and 18 received radiotherapy followed by surgery; in five cases a combination of chemo-radiotherapy was used. Multivariate analysis identified T classification, orbit invasion, N classification, site of origin of tumour in nasal fossae, and no surgical resection as independent prognostic factors (p=0.0001). CONCLUSION: T4 tumours with orbit invasion present bad prognosis as compared to other T4 tumours. Surgical resection should be included in the treatment strategy. Because of the high frequency of lymph-node metastasis, neck treatment should be considered in T4 tumours. 相似文献
89.
Laissy JP Menegazzo D Debray MP Toublanc M Ravery V Dumont E Schouman-Claeys E 《European radiology》2000,10(7):1138-1143
The aim of this study was to evaluate the usefulness of gadolinium-enhanced time-of-flight magnetic resonance venography
(MRV) in the diagnosis of bland thrombosis/tumoral invasion in the preoperative assessment of renal cell carcinoma. Preoperative
precontrast and enhanced GRE fast low-angle shot (FLASH) images of 36 patients with renal adenocarcinoma were reviewed and
compared with pre- and post-contrast T1-weighted images. All patients underwent surgery, and MR findings were blindly and
prospectively compared with surgical and pathologic data, considered the standard. Renal vein and vena cava were involved
in 17 and 9 patients, respectively; right atrial extension was present in one patient. Precontrast spin-echo (SE) and FLASH
images were 88 % sensitive and 100 % specific in the detection of venous involvement, respectively, and enhanced FLASH images
100 % sensitive and 96 % specific. The nature of thrombus (neoplastic or bland) was more accurately assessed (McNemar's, p < 0.05) with FLASH-enhanced MR images (sensitivity 89 %; specificity 96 %) than with SE and precontrast FLASH images (sensitivity
79 %; specificity 94 %). Our data suggest that use of Gd-enhanced MRV might improve preoperative assessment of vascular involvement
in renal carcinoma.
Received: 7 September 1999; Revised: 26 November 1999; Accepted: 26 November 1999 相似文献
90.
【摘要】 目的 探讨长链非编码RNA TUSC8调控miR 137对宫颈癌迁移和侵袭的影响及其机制。方法 qPCR检测TUSC8和miR 137在宫颈癌组织和正常宫颈组织中的表达情况及差异,分析TUSC8与宫颈癌患者临床病理学参数之间的相关关系,双荧光素酶报告基因检测TUSC8与miR 137之间的相互作用;Transwell侵袭实验检测抑制TUSC8后宫颈癌细胞侵袭行为的变化情况;划痕愈合实验检测抑制TUSC8后宫颈癌细胞迁移行为的变化情况;裸鼠体内成瘤实验抑制TUSC8后宫颈癌细胞的成瘤能力的变化。结果 与正常宫颈组织相比,宫颈癌组织中TUSC8和miR 137的表达水平均相对上调,差异有统计学意义(P<005);TUSC8的表达与宫颈癌的病理分期相关以及淋巴结转移情况有关,分期越高,TUSC8在宫颈癌组织中表达越高,淋巴结转移的患者中TUSC8的表达也相对较高;双荧光素酶实验证实TUSC8能与miR 137的3’ UTR特异性结合,可以调控miR 137的表达与活性;抑制TUSC8的表达后可以抑制宫颈癌细胞的迁移和侵袭能力;抑制TUSC8后宫颈癌细胞的成瘤能力受到相应的抑制。结论 TUSC8可以调控miR 137的表达影响宫颈癌细胞的迁移和侵袭行为。 相似文献