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41.
目的 研究活血解毒方对缺氧/复氧(H/R)所致的心肌细胞凋亡的影响。方法 体外培养H9C2心肌细胞并分成正常对照组(Control组)、缺氧复氧组(H/R组)、H/R + 活血解毒中药组、LY294002组和活血解毒中药 + LY294002组,其中正常对照组给予DMEM培养基培养,缺氧复氧组给予缺氧4 h、复氧6 h处理,缺氧复氧 + 活血解毒中药组、LY294002组和活血解毒中药 + LY294002组分别给予活血解毒中药、LY294002、活血解毒中药配合LY294002预处理24 h,然后均给予缺氧4 h、复氧6 h处理。采用CCK8检测各组心肌细胞的存活率,流式细胞术检测各组细胞凋亡水平,电镜观察各组心肌细胞中线粒体、自噬体的变化,Western Blot检测各组细胞凋亡蛋白半胱氨酸天冬氨酸蛋白酶3(Caspase3)、半胱氨酸天冬氨酸蛋白水解酶3(Cleaved caspase3)、β-连环蛋白(β-Catenin)、p-p65、B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)蛋白的表达。结果 活血解毒方预处理显著增加H/R诱导的H9C2心肌细胞凋亡,降低凋亡相关蛋白Cleaved caspase3、β-Catenin、p-p65表达,增加Bcl-2表达。结论 活血解毒方可通过抑制细胞凋亡,降低缺氧/复氧所致的心肌细胞损伤,其作用机制可能与PI3K信号通路相关。 相似文献
42.
Biliary tract cancers (BTCs) are a group of invasive neoplasms, with increasing incidence and dismal prognosis. In advanced disease, the standard of care is represented by first-line chemotherapy with cisplatin and gemcitabine. In subsequent lines, no clear recommendations are currently available, highlighting the need for novel therapeutic approaches.The PI3K/AKT/mTOR pathway is a core regulator of cell metabolism, growth and survival, and is involved in BTCs carcinogenesis and progression. Mutations, gene copy number alterations and aberrant protein phosphorylation of PI3K, AKT, mTOR and PTEN have been thoroughly described in BTCs and correlate with poor survival outcomes.Several pre-clinical evidences state the efficacy of PI3K/AKT/mTOR pathway inhibitors in BTCs, both in vitro and in vivo. In the clinical setting, initial studies with rapamycin analogs have shown interesting activity with an acceptable toxicity profile. Novel strategies evaluating AKT and PI3K inhibitors have risen serious safety concerns, pointing out the need for improved patient selection and increased target specificity for the clinical development of these agents, both alone and in combination with chemotherapy.This review extensively describes the role of the PI3K/AKT/mTOR pathway in BTCs and examines the rationale of its targeting in these tumors, with particular focus on clinical activity, toxicities and perspectives on further development of PI3K/AKT/mTOR pathway inhibitors. 相似文献
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The interactions of cancer cells within a solid mass with the surrounding reactive stroma are critical for growth and progression. The surrounding vasculature is recruited into the periphery of the growing tumour to supply cancer cells with nutrients and O2. This study focuses on developing a novel three-dimensional (3-D) in vitro biomimetic colorectal cancer model using colorectal cancer cells and connective tissue cells. The 3-D model comprises a dense artificial cancer mass, created by partial plastic compression of collagen type I containing HT29 colorectal cancer cells, nested in a non-dense collagen type I gel populated by fibroblasts and/or endothelial cells. HT29 cells within the dense mass proliferate slower than when cultured in a two-dimensional system. These cells form tumour spheroids which invade the surrounding matrix, away from the hypoxic conditions in the core of the construct, measured using real time O2 probes. This model is also characterized by the release of vascular endothelial growth factor (VEGF) by HT29 cells, mainly at the invading edge of the artificial cancer mass. This characterization is fundamental in establishing a reproducible, complex model that could be used to advance our understanding of cancer pathology and will facilitate therapeutic drug testing. 相似文献
46.
《药学学报(英文版)》2021,11(11):3481-3492
Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths, characterized by highly hypoxic tumor microenvironment. Hypoxia-inducible factor-1α (HIF-1α) is a major regulator involved in cellular response to changes of oxygen levels, supporting the adaptation of tumor cells to hypoxia. Bruceine D (BD) is an isolated natural quassinoid with multiple anti-cancer effects. Here, we identified BD could significantly inhibit the HIF-1α expression and its subsequently mediated HCC cell metabolism. Using biophysical proteomics approaches, we identified inhibitor of β-catenin and T-cell factor (ICAT) as the functional target of BD. By targeting ICAT, BD disrupted the interaction of β-catenin and ICAT, and promoted β-catenin degradation, which in turn induced the decrease of HIF-1α expression. Furthermore, BD could inhibit HCC cells proliferation and tumor growth in vivo, and knockdown of ICAT substantially increased resistance to BD treatment in vitro. Our data highlight the potential of BD as a modulator of β-catenin/HIF-1α axis mediated HCC metabolism. 相似文献
47.
血管内皮生长因子(VEGF)对血管生成、炎症、肿瘤等的发生及发展具有重要的作用,并J~VEGF受低氧的严密调控,而胎盘生长因子(PIGF)是血管内皮生长因子的家族成员,目前对PIGF的研究尚少,本文就PIGF和低氧关系进行综述。 相似文献
48.
Chemokines are vital regulators of cell mobilization for immune surveillance, inflammation, and development. Chemokines signal through binding to their receptors that are a superfamily of seven-transmembrane domain G-coupled receptors. Recently, a complete repertoire of both CC and CXC chemokines have been identified in channel catfish, but nothing is known about their receptors. In this study, a set of 29 CC chemokine receptor (CCR) genes and 8 CXC chemokine receptor (CXCR) genes were identified and annotated from the channel catfish genome. Extensive phylogenetic and comparative genomic analyses were conducted to annotate these genes, revealing fish-specific CC chemokine receptors, and lineage-specific tandem duplications of chemokine receptors in the teleost genomes. With 29 genes, the channel catfish genome harbors the largest numbers of CC chemokine receptors among all the genomes characterized. Analysis of gene expression after bacterial infections indicated that the chemokine receptors were regulated in a gene-specific manner. Most differentially expressed chemokine receptors were up-regulated after Edwardsiella ictaluri and Flavobacterium columnare infection. Among which, CXCR3 and CXCR4 were observed to participate in immune responses to both bacterial infections, indicating their potential roles in catfish immune activities. In addition, CXCR3.2 was significantly up-regulated in ESC-susceptible fish, and CXCR4b was mildly induced in ESC-resistant fish, further supporting the significant roles of CXCR3 and CXCR4 in catfish immune responses. CXCR4b and CCR9a were both up-regulated not only after bacterial infection, but also after hypoxia stress, providing the linkage between bacterial infection and low oxygen stresses. These results should be valuable for comparative immunological studies and provide insights into their roles in disease and stress responses. 相似文献
49.
卢欣 《中国实用神经疾病杂志》2012,15(11):10-11
目的探讨氢气对乳鼠海马神经元细胞缺氧/复氧损伤后细胞活力的影响。方法原代培养的SD乳鼠海马神经元细胞,随机分成对照组,缺氧/复氧组和氢气预处理组。对照组常规培养;缺氧/复氧组在100%N2中培养15min后复氧30min;氢气预处理组在2%H2+98%N2中培养15min后复氧30min。采用MTT法检测乳鼠海马神经元细胞活力。结果氢气预处理能够增强细胞活力(P<0.05)。结论氢气预处理对海马神经元细胞缺氧/复氧损伤具有保护作用,可能与提高细胞活力有关。 相似文献
50.
低氧诱导促有丝分裂因子(hypoxia-induced mitogenic factor,HIMF)是一种相对分子质量为9 400,富含半胱氨酸的分泌蛋白,最初在鼠的肺组织用卵清蛋白诱发哮喘模型时发现的.HIMF由111个氨基酸残基组成,其结构分为3个组分:①N末端信号序列;②中间可变区;③高度保守的C末端信号序列.已经证实用短发夹环RNA敲减低氧性肺动脉高压大鼠的HIMF基因,能够阻止平均肺动脉压升高、降低肺血管阻力、减轻右心室肥厚以及改善慢性缺氧引起的血管重塑作用.本文主要就HIMF在低氧性肺动脉高压的作用及机制研究作一综述. 相似文献