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51.
目的:探讨口腔鳞癌组织中免疫共刺激分子PD-L1与细胞外基质蛋白酶诱导因子CD147的表达、两者的相关性及临床意义。方法:应用免疫组化技术检测66例口腔鳞癌组织及36例正常口腔黏膜组织中PD-L1和CD147的表达,分析PD-L1、CD147表达的相关性及二者与口腔鳞癌临床病理参数的关系。结果:PD-L1在口腔鳞癌组织中表达阳性率为68.18%(45/66),正常口腔黏膜组织中表达阳性率仅为16.67%(6/36);CD147在口腔鳞癌组织中表达阳性率为74.24%(49/66),明显高于其在正常口腔黏膜组织中的表达13.88%(5/36)。PD-L1和CD147两者在口腔鳞癌组织中阳性表达率与口腔黏膜组织相比均明显升高(P0.01)。统计学分析显示,PD-L1和CD147在口腔鳞癌组织中的高表达与患者的性别年龄、吸烟史及肿瘤的体积等因素无明显相关,但与TNM分期及鳞癌的组织分化程度紧密相关。口腔鳞癌组织中PD-L1与CD147两者相关性分析r=0.342,P值小于0.01,说明二者的表达呈显著正相关。结论:口腔鳞癌组织中PD-L1与CD147均呈高表达,并且二者的过度表达可能与口腔鳞癌的发生、发展关系密切,合并检测二者可能为OSCC的诊疗及预后指明新的方向,为口腔鳞癌的靶向治疗提供新的靶点。 相似文献
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《Molecular & cellular proteomics : MCP》2019,18(1):51-64
Highlights
- •microRNA-222 attenuates TGEV-induced mitochondrial dysfunction.
- •microRNA-222 downregulates THBS1 and CD47.
- •THBS1 is the target of microRNA-222 during TGEV infection.
- •THBS1 and CD47 increase mitochondrial Ca2+ level and reduced mitochondrial membrane potential (MMP).
54.
Hailin Tang Cailu Song Feng Ye Guanfeng Gao Xueqi Ou Lijuan Zhang Xinhua Xie Xiaoming Xie 《Journal of cellular and molecular medicine》2019,23(12):8114-8127
Resistance to trastuzumab remains a major obstacle in HER2‐overexpressing breast cancer treatment. miR‐200c is important for many functions in cancer stem cells (CSCs), including tumour recurrence, metastasis and resistance. We hypothesized that miR‐200c contributes to trastuzumab resistance and stemness maintenance in HER2‐overexpressing breast cancer. In this study, we used HER2‐positive SKBR3, HER2‐negative MCF‐7, and their CD44+CD24? phenotype mammospheres SKBR3‐S and MCF‐7‐S to verify. Our results demonstrated that miR‐200c was weakly expressed in breast cancer cell lines and cell line stem cells. Overexpression of miR‐200c resulted in a significant reduction in the number of tumour spheres formed and the population of CD44+CD24? phenotype mammospheres in SKBR3‐S. Combining miR‐200c with trastuzumab can significantly reduce proliferation and increase apoptosis of SKBR3 and SKBR3‐S. Overexpression of miR‐200c also eliminated its downstream target genes. These genes were highly expressed and positively related in breast cancer patients. Overexpression of miR‐200c also improved the malignant progression of SKBR3‐S and SKBR3 in vivo. miR‐200c plays an important role in the maintenance of the CSC‐like phenotype and increases drug sensitivity to trastuzumab in HER2+ cells and stem cells. 相似文献
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谭健安 《基因组学与应用生物学》2019,(1):484-488
本研究将CD47-si RNA转染至食道癌细胞,采用蛋白免疫印迹检测食道癌细胞中CD47蛋白的表达,MTT法检测CD47-siRNA转染组和空质粒转染组(对照组)食道癌细胞增殖状态,蛋白免疫印迹检测CD47-siRNA转染组和空质粒转染组(对照组)食道癌细胞中PCNA蛋白表达,DCFDA染色流式细胞仪检测食道癌细胞CD47-siRNA转染组和空质粒转染组(对照组)中ROS水平,以探究CD47基因对食道癌发生发展的影响。研究结果表明,CD47-si RNA转染组食道癌细胞中CD47蛋白明显低于对照组;CD47-siRNA转染组食道癌细胞增殖率显著低于对照组(p<0.05);CD47-siRNA转染组细胞增殖相关蛋白PCNA低于对照组(p<0.01);CD47-siRNA转染组食道癌细胞中ROS水平明显高于对照组(p<0.05)。本研究初步认为:CD47-siRNA可降低食道癌细胞中CD47蛋白表达,抑制食道癌细胞的增殖并增加食道癌细胞中ROS水平。 相似文献
57.
Osman Yipkin Calhan Sean Wyatt Alun Millward Davies 《Developmental neurobiology》2019,79(11-12):949-962
CD40‐activated CD40L reverse signaling is a major physiological regulator of the growth of neural processes in the developing nervous system. Previous work on superior cervical ganglion (SCG) neurons of the paravertebral sympathetic chain has shown that CD40L reverse signaling enhances NGF‐promoted axon growth and tissue innervation. Here we show that CD40L reverse signaling has the opposite function in prevertebral ganglion (PVG) sympathetic neurons. During a circumscribed perinatal window of development, PVG neurons cultured from Cd40–/– mice had substantially larger, more exuberant axon arbors in the presence of NGF than PVG neurons cultured from wild‐type mice. Tissues that receive their sympathetic innervation from PVG neurons were markedly hyperinnervated in Cd40–/– mice compared with wild‐type mice. The exuberant axonal growth phenotype of cultured CD40‐deficient perinatal PVG neurons was pared back to wild‐type levels by activating CD40L reverse signaling with a CD40‐Fc chimeric protein, but not by activating CD40 forward signaling with CD40L. The co‐expression of CD40 and CD40L in PVG neurons suggests that these proteins engage in an autocrine signaling loop in these neurons. Our work shows that CD40L reverse signaling is a physiological regulator of NGF‐promoted sympathetic axon growth and tissue innervation with opposite effects in paravertebral and prevertebral neurons. 相似文献
58.
Pasquale D'Acunzo Tal Hargash Monika Pawlik Chris N. Goulbourne Rocío Prez‐Gonzlez Efrat Levy 《Developmental neurobiology》2019,79(7):656-663
Down syndrome (DS) is a human genetic disease caused by trisomy of chromosome 21 and characterized by early developmental brain abnormalities. Dysfunctional endosomal pathway in neurons is an early event of DS and Alzheimer's disease. Recently, we have demonstrated that exosome secretion is upregulated in human DS postmortem brains, in the brain of the trisomic mouse model Ts[Rb(12.1716)]2Cje (Ts2) and by DS fibroblasts as compared with disomic controls. High levels of the tetraspanin CD63, a regulator of exosome biogenesis, were observed in DS brains. Partially blocking exosome secretion by DS fibroblasts exacerbated a pre‐existing early endosomal pathology. We thus hypothesized that enhanced CD63 expression induces generation of intraluminal vesicles (ILVs) in late endosomes/multivesicular bodies (MVBs), increasing exosome release as an endogenous mechanism to mitigate endosomal abnormalities in DS. Herein, we show a high‐resolution electron microscopy analysis of MVBs in neurons of the frontal cortex of 12‐month‐old Ts2 mice and littermate diploid controls. Our quantitative analysis revealed that Ts2 MVBs are larger, more abundant, and contain a higher number of ILVs per neuron compared to controls. These findings were further corroborated biochemically by Western blot analysis of purified endosomal fractions showing higher levels of ILVs proteins in the same fractions containing endosomal markers in the brain of Ts2 mice compared to controls. These data suggest that upregulation of ILVs production may be a key homeostatic mechanism to alleviate endosomal dysregulation via the endosomal–exosomal pathway. 相似文献
59.
Nicola Vannini Vasco Campos Mukul Girotra Vincent Trachsel Shanti Rojas-Sutterlin Josefine Tratwal Simone Ragusa Evangelos Stefanidis Dongryeol Ryu Pernille Y. Rainer Gena Nikitin Sonja Giger Terytty Y. Li Aikaterini Semilietof Aurelien Oggier Yannick Yersin Loïc Tauzin Eija Pirinen Olaia Naveiras 《Cell Stem Cell》2019,24(3):405-418.e7
60.