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51.
转化生长因子α,β1对大鼠肺泡Ⅱ型细胞生长的影响   总被引:2,自引:0,他引:2  
Zeng Q  Qian Z  Su T  Sun Q  Jiang H 《中华病理学杂志》1999,28(6):432-435
目的 探讨转化生长因子α和β1对肺泡Ⅱ型细胞增生的影响及其作用机制。方法 采用原代培养的成年大鼠肺泡Ⅱ型细胞,加入TGFα、TGFβ1作用48小时,测定肺泡Ⅱ型细^3H-TdR掺入量和细胞数量,并用斑点杂交、原位杂交和免疫组化方法检测细胞内细胞周期蛋白D1、细胞周期依赖性激酶4 mRNA和蛋白的表达。结果 随TGFα浓度递增,肺泡Ⅱ型细胞^3H-TdR掺入量和细胞数量均逐渐增加,呈量效正相关;TG  相似文献   
52.
Immunocytochemical studies of postmortem human tissue have shown that the neurons at risk for degeneration in Alzheimer’s are marked by the ectopic expression of several cell cycle components. The current work investigates the roles that β-amyloid activated microglia might play in leading neurons to re-express cell cycle components. Stable cultures of E16.5 mouse cortical neurons were exposed to β-amyloid alone, microglial cells alone, or microglial cells activated by β-amyloid. Increased cell death was found in response to each of these treatments, however, only the amyloid activated microglial treatment increased the number of neurons that were positive for cell cycle markers such as PCNA or cyclin D and incorporation of BrdU. Double labeling with BrdU and TUNEL techniques verified that the ‘dividing’ neurons were dying, most likely through an apoptotic mechanism. The identity of the soluble factor(s) elaborated by the microglia remains unknown, but FGF2, a suspected neuronal mitogen, was ruled out. These results further support a model in which microglial activation by β-amyloid is a key event in the progression in Alzheimer’s disease.  相似文献   
53.
In this report, we demonstrate that the sulfated polysaccharide, Haishen (HS), which was isolated from the body wall of the sea cucumber Stichopus japonicus can induce morphological transformation and proliferation of astrocytes in vitro when combined with basic fibroblast growth factor 2 (FGF-2). Cell morphology showed no change when induced by HS or FGF-2 alone. However, combinational treatment of HS and FGF-2 promoted transformation of normal astrocyte into a stella morphology (stellation), along with an increase in the expression and rearrangement of glial fibrillary acidic protein (GFAP). Further analysis of HS- and FGF-2-treated cells indicated a reduced percentage of cells in the G0/G1 phase, whereas the cell proliferation index (S phase) was increased. The proportion of 5-bromo-2-deoxyuridine (BrdU)-positive cells increased in response to the combination of HS and FGF-2. With respect to cell cycle signaling, immunoblotting assay demonstrated an accumulation of Cyclin D1. These observations suggest that HS may play a role in astrocyte morphological transformation and proliferation, and this activation requires a synergism with FGF-2.  相似文献   
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55.
目的:探讨Cyclin D1 shRNA(short hairpin RNA)对骨肉瘤细胞系SOSP-9607增殖和凋亡的影响.方法:利用Cyclin D1 shRNA表达载体,稳定转染骨肉瘤细胞系SOSP-9607,分别采用RT-PCR和Western blot分别从mRNA水平和蛋白水平上检测Cyclin D1的变化;流式细胞术检测骨肉瘤细胞Cyclin D1周期和凋亡率的变化;CCK-8检测干涉Cyclin D1对骨肉瘤细胞增殖的影响.结果:稳定转染Cyclin D1 shRNA载体后骨肉瘤细胞的Cyclin D1 mRNA和蛋白的表达均被明显抑制.与对照组相比,骨肉瘤细胞增殖被显著抑制(P<0.05).同时,细胞发生G0/1期阻滞,G1/S期比例增加(P<0.01).结论:Cyclin D1 shRNA载体可下调目的基因的表达,有效的抑制骨肉瘤细胞SOSP-9607的增殖,发生G1/S期阻滞.  相似文献   
56.
宫颈癌是全球女性最常见的恶性肿瘤之一,居女性生殖器官恶性肿瘤首位.人乳头瘤病毒(HPV)感染是宫颈癌的主要危险因素.HPV基因与宫颈组织基因相互融合,引起宫颈病变缓慢进展,从慢性炎症、低度不典型增生、高度不典型增生到癌变.从分子水平探索HPV基因与宫颈癌发病机制,寻找早期诊断、有效治疗和评估预后的新靶点是国内外学者研究...  相似文献   
57.
Interaction of human papilloma virus oncoproteins E6 and E7 with cell cycle proteins leads to disturbances of the cell cycle mechanism and subsequent alteration in the expression of some proteins, such as p16INK4a, cyclin D1, p53 and KI67. In this study, we compared alterations in the expression of these proteins during several stages of intra-epitelial cervical carcinogenesis. Accordingly, an immunohistochemical study was performed on 50 cervical biopsies, including negative cases and intraepithelial neoplasias. The expression patterns of these markers were correlated with the histopathological diagnosis and infection with HPV. The p16INK4a, followed by Ki67, showed better correlation with cancer progression than p53 and cyclin D1, which recommends their use in the evaluation of cervical carcinogenesis. These monoclonal antibodies can be applied to cervical biopsy specimens to identify lesions transformed by oncogenic HPV, separating CIN 1 (p16INK4a positive) and identifying high-grade lesions by an increase in the cellular proliferation index (Ki67). In this way, we propose immunomarkers that can be applied in clinical practice to separate patients who need a conservative therapeutic approach from those who require a more aggressive treatment.  相似文献   
58.
目的观察NKD1、β-catenin和Cyclin D1蛋白在结直肠正常黏膜、腺瘤和腺癌组织中的表达,探讨NKD1、β-catenin和Cyclin D1在结直肠正常黏膜-腺瘤-腺癌这一癌变过程中的表达变化及临床意义。方法应用免疫组化SP法检测38例结直肠正常黏膜、70例腺瘤、128例腺癌组织中NKD1、β-catenin和Cyclin D1蛋白的表达。结果 NKD1在结直肠正常黏膜、腺瘤、腺癌组织中的阳性率依次降低(P0.05),其在轻度异型增生腺瘤组织中的阳性率高于重度异型增生腺瘤组织(P0.05);β-catenin异位表达率与Cyclin D1阳性率在结直肠正常黏膜、腺瘤、腺癌组织中均依次升高(P0.01),且Cyclin D1在重度异型增生腺瘤组织中的阳性率高于中度及轻度异型增生腺瘤(P0.05)。NKD1、β-catenin、Cyclin D1在结直肠腺癌组织中的表达均与癌分化程度、Duke分期、淋巴结转移有关(P0.05)。在结直肠腺癌组织中NKD1的阳性率和β-catenin异位表达率呈负相关(r_s=-0.645,P0.01)。在结直肠腺癌组织中β-catenin异位表达率和Cyclin D1阳性率呈正相关(r_s=0.618,P0.01)。结论 NKD1、β-catenin、Cyclin D1三者可能参与结直肠肿瘤的发生、发展,有望成为评价结直肠腺癌恶性程度及预后的指标。  相似文献   
59.
BACKGROUND:Bone marrow mesenchymal stem cells can migrate into tumor tissues, as reported in recent studies. OBJECTIVE:To investigate the tropism and effect of transplantation of bone marrow mesenchymal stem cells on proliferation and differentiation of gastric cancer cell line SGC7901 in rats. METHODS:Gastric cancer models were established in Sprague-Dawley rats by subcutaneous injection of gastric cancer cell line SGC7901, and then, in cell transplantation group, each rat underwent an intraperitoneal injection of 1×107 bone marrow mesenchymal stem cells. After transplantation, the targeting ability of bone marrow mesenchymal stem cells was detected using fluorescent DiI labeling. Cyclin D2 mRNA and protein expressions were measured using real-time PCR and western blot assay, respectively. Apoptosis of gastric cancer cells was observed by in situ terminal labeling method. RESULTS AND METHODS: Bone marrow mesenchymal stem cells successfully migrated into the gastric cancer site in rats. The expression levels of cyclin D2 mRNA and protein in the cell transplantation group were significantly higher than those in the model group (P < 0.05). It was observed that the number of apoptotic cancer cells was significantly reduced in the cell transplantation group compared with the model group (P < 0.05). These findings indicate that bone marrow mesenchymal stem cells have the ability to migrate into the tumor sites, thereby promoting the proliferation of gastric cancer cells.  相似文献   
60.
 目的:探索异丹叶大黄素(ISO)下调肿瘤细胞中细胞周期蛋白D1表达的分子机制。方法:以ISO作用于人源性膀胱癌UMUC3、RT12和RT4细胞后用Western blotting法检测细胞周期蛋白D1表达水平;以RT-PCR法检测细胞周期蛋白D1 mRNA的表达水平。稳定转染细胞周期蛋白D1启动子萤光素酶报告基因至UMUC3细胞并筛选后,检测ISO预处理后萤光素酶活性。ISO预处理UMUC3细胞后,提取核蛋白检测核转录因子表达水平的变化。分别稳定转染GFP和GFP-细胞周期蛋白D1表达构建载体,筛选克隆;ISO预处理后,Western blotting法检测细胞周期蛋白D1的蛋白表达水平, 贴壁依赖性细胞生长实验法检测细胞生长能力的变化,流式细胞术检测细胞周期的变化。分别稳定转染人源性细胞周期蛋白D1野生型和-163位点突变型萤光素酶报告基因质粒载体至UMUC3细胞并筛选,ISO预处理后检测细胞的萤光素酶活性。最后利用染色质免疫沉淀的方法,以抗Sp1抗体检测ISO对Sp1与细胞周期蛋白D1启动子结合力的影响。结果:ISO可从mRNA和蛋白水平显著抑制肿瘤细胞的细胞周期蛋白D1水平,并且是从内源性转录水平来抑制细胞周期蛋白D1的转录。ISO可抑制、下调核转录因子Sp1的表达,并抑制Sp1与细胞周期蛋白D1启动子区域的结合力,该结合位点主要位于启动子-92到+27 bp的5’-非翻译区。结论:ISO可通过下调Sp1核转录因子表达及其与细胞周期蛋白D1启动子的结合,从内源性转录水平来抑制细胞周期蛋白D1的表达,从而诱导G 0/G 1细胞周期阻滞并抑制肿瘤细胞增殖。我们的研究将为临床中药单体ISO综合治疗肿瘤提供新的策略。  相似文献   
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