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51.
目的:通过莪黄灌肠液对SW480细胞HIF-1α通路uPA、uPAR基因表达的影响,探讨莪黄灌肠液对SW480细胞侵袭与迁移的影响。方法:根据随机数学分组的原则,将50只健康SD雄性大鼠分成随机5组并逐个编号,体重控制在(200±20)g。通过预实验得出的药物分组量分别灌胃给药:莪黄灌肠液(莪黄汤)每毫升药液中含生药2 g,莪黄灌肠液(莪黄汤)组由低、中、高(6.075 g/kg,12.15 g/kg,24.3 g/kg)剂量组(灌胃剂量2 ml)组成,空白组为生理盐水组(灌胃剂量2 ml,pH 7.2),阳性对照组由腹腔注射氟尿嘧啶0.025 g/(kg·d),调整注射剂量1 ml构成。标准化灌胃1周,无菌条件下提取各组含药血清。在体外使用含药血清体培养SW480细胞,划痕实验观察莪黄灌肠液含药血清在体外对SW480细胞迁移能力的影响;Transwell实验检测肿瘤细胞侵袭能力;Western-blot实验检测各组细胞中HIF-1α、uPA、uPAR蛋白表达。结果:预实验提示莪黄灌肠液对大鼠无明显副作用。SW480细胞具有明显的迁移及侵袭能力。各组莪黄灌肠液含药血清能抑制SW480细胞的侵袭与迁移特性,其中莪黄灌肠液各组(24.3 g/kg,12.15 g/kg,6.075 g/kg)和氟尿嘧啶组较空白组均能够有效抑制肿瘤细胞的侵袭与迁移作用,且氟尿嘧啶组作用最强,中药24.3 g/kg组表现出的抑制侵袭作用较12.15 g/kg,6.075 g/kg组均强(P<0.05)。莪黄灌肠液含药血清作用于肿瘤细胞24 h后,其细胞内HIF-1α、uPA、uPAR蛋白含量均有明显的下降,HIF-1α、uPA、uPAR蛋白表现出浓度依赖性(P<0.05)。结论:“莪黄灌肠液”可能通过作用于HIF-1α通路抑制SW480细胞的侵袭与转移。  相似文献   
52.
吕丽  林劼 《肿瘤防治研究》2020,47(4):243-250
近年来,免疫治疗在多种恶性肿瘤治疗中取得突破性进展,为肿瘤患者带来明显生存获益。然而,免疫系统在识别和杀伤肿瘤细胞的同时,出现免疫编辑诱导,导致大多数患者对免疫治疗具有先天或后天的耐药性。肿瘤免疫编辑是免疫系统抑制或促进肿瘤发生发展的过程,肿瘤的发生发展经历了免疫消除、免疫平衡和免疫逃逸三个阶段。在整个过程中,肿瘤的免疫原性被编辑,并获得使疾病进展的各种免疫抑制机制,致使肿瘤细胞逃避免疫系统的监测,导致肿瘤细胞免疫逃逸产生耐药。因此,揭示肿瘤免疫治疗耐药机制及克服耐药至关重要。本文主要从肿瘤免疫编辑过程背后的机制对肿瘤免疫治疗耐药作一具体阐述,为临床中克服免疫耐药取得更好疗效提供参考。  相似文献   
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In clear cell renal cell carcinoma (ccRCC), glycolysis is enhanced mainly because of the increased expression of key enzymes in glycolysis. Hence, the discovery of new molecular biomarkers for glycolysis may help guide and establish a precise system of diagnosis and treatment for ccRCC. Expression profiles of 1079 tumor samples of ccRCC patients (including 311 patients treated with everolimus or nivolumab) were downloaded from public databases. Proteomic profiles of 232 ccRCC samples were obtained from Fudan University Shanghai Cancer Center (FUSCC). Biological changes, tumor microenvironment and prognostic differences were explored between samples with various glycolysis characteristics. There were significant differences in CD8+ effector T cells, epithelial-to-mesenchymal transition and pan-fibroblast TGFb between the Low and High glyScore groups. The tumor mutation burden of the Low glyScore group was lower than that of the High glyScore group. And higher glyScore was significantly associated with worse overall survival (OS) in 768 ccRCC patients (P < .0001). External validation in FUSCC cohort also indicated that glyScore was of strong ability for predicting OS (P < .05). GlyScore may serve as a biomarker for predicting everolimus response in ccRCC patients due to its significant associations with progression-free survival (PFS). And glyScore may also predict overall survival in patients treated with nivolumab. We calculated the glyScore in ccRCC and the defined glyScore was of strong ability for predicting OS. In addition, glyScore may also serve as a biomarker for predicting PFS in patients treated with everolimus and could predict OS in patients treated with nivolumab.  相似文献   
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Objective: Hepatocellular carcinoma (HCC) microenvironment has been recognized as a key contributor for cancer progression, metastasis, and drug resistance. The crosstalk between tumor cells, the vascular endothelial growth factor (VEGF), and the chemokine (C-C motif) ligand 2 (CCL2) signaling networks mediates immunoinhibitory impact and facilitates tumor angiogenesis. The current investigation aimed at exploring the potent anti-cancer activity of the newly designed nano-based anti-cancer therapy comprising anti-VEGF drug, avastin (AV), and CCR2 antagonist (CR) to counteract HCC and tracking its mode of action in vivo. Methods: The prepared AV, CR, and AVCR nanoprototypes were characterized by nanoscale characterization techniques in our previous work. Here, they are applied for unearthing their anti-cancer properties / mechanisms in hepatic cancer-induced rats via analyzing protein levels and genetic expression of the elements incorporated in the angiogenesis, apoptosis, and metastasis signalling pathways. Results: The present results revealed a significant down-regulation in the angiogenesis, survival and metastasis indices along with up-regulation in the pro-apoptotic mediators upon treatment of hepatic cancer-bearing rats with the novel synthesized nanomaterials when compared with the untreated counterparts. We showed across HCC model that anti-VEGF in combination with CCR2 antagonism therapy leads to sensitization and enhanced tumor response over anti-VEGF or CCR2 antagonism monotherapy, particularly in its nanoscale formulation. Conclusion: The present approach provides new mechanistic insights into the powerful anti-hepatic cancer advantage of the novel nanoprototypes which is correlated with modulating critical signal transduction pathways implicated in tumor microenviroment such as angiogenesis, apoptosis and metastasis. This research work presents a substantial foundation for future studies focused on prohibiting cancer progression and recovery by targeting tumor microenviroment.  相似文献   
58.
《Cancer cell》2022,40(8):818-834.e9
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The mechanisms linking tumor microenvironment acidosis to disease progression are not understood. Here, we used mammary, pancreatic, and colon cancer cells to show that adaptation to growth at an extracellular pH (pHe) mimicking acidic tumor niches is associated with upregulated net acid extrusion capacity and elevated intracellular pH at physiological pHe, but not at acidic pHe. Using metabolic profiling, shotgun lipidomics, imaging and biochemical analyses, we show that the acid adaptation-induced phenotype is characterized by a shift toward oxidative metabolism, increased lipid droplet-, triacylglycerol-, peroxisome content and mitochondrial hyperfusion. Peroxisome proliferator-activated receptor-α (PPARA, PPARα) expression and activity are upregulated, at least in part by increased fatty acid uptake. PPARα upregulates genes driving increased mitochondrial and peroxisomal mass and β-oxidation capacity, including mitochondrial lipid import proteins CPT1A, CPT2 and SLC25A20, electron transport chain components, peroxisomal proteins PEX11A and ACOX1, and thioredoxin-interacting protein (TXNIP), a negative regulator of glycolysis. This endows acid-adapted cancer cells with increased capacity for utilizing fatty acids for metabolic needs, while limiting glycolysis. As a consequence, the acid-adapted cells exhibit increased sensitivity to PPARα inhibition. We conclude that PPARα is a key upstream regulator of metabolic changes favoring cancer cell survival in acidic tumor niches.  相似文献   
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