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101.
目的:探讨黄连素对人胃癌细胞SGC7901凋亡的影响。方法:MTS法检测不同浓度的黄连素(100、150、200μmol/L)对胃癌细胞的抑制作用,Hoechst 33258染色检测不同浓度的黄连素(100、150、200μmol/L)对细胞凋亡的影响;Real Time Q-PCR检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的mRNA表达;Western blot检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的蛋白表达。结果:不同浓度的黄连素能显著降低人胃癌细胞SGC701活性(P<0.05,P<0.01),促进其凋亡,升高Cleaved Caspase-3、Bax的mRNA和蛋白表达水平(P<0.05,P<0.01),降低Bcl-2的mRNA和蛋白表达水平(P<0.05,P<0.01)。结论:不同浓度的黄连素可诱导胃癌细胞凋亡,其机制可能与升高Cleaved Caspase-3、Bax的表达,降低Bcl-2的表达有关。 相似文献
102.
Alicia M. Blessing MD PhD Janice M. Santiago-O'Farrill MD PhD Weiqun Mao BS MD Lan Pang BS MD Jing Ning MD PhD Daewoo Pak MD PhD Lakshmi Reddy Bollu MD PhD Philip Rask BS MD LaKesla Iles BS MD Hailing Yang PhD MD Samantha Tran BS MD Ezzeddine Elmir BS MD Geoffrey Bartholomeusz MD PhD Robert Langley MD PhD Zhen Lu MD Robert C. Bast Jr MD 《Cancer》2020,126(15):3579-3592
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105.
磷脂酰肌醇3-激酶(phosphoinositide 3-kinase,PI3K)/蛋白激酶B(protein kinase B,AKT)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)信号转导通路在多种肿瘤中异常激活,参与肿瘤细胞增殖、分化和凋亡等生命过程的调控,是抗肿瘤药物研发的重要靶点。对目前已应用于乳腺癌临床或处于临床试验阶段的PI3K/AKT/mTOR信号通路抑制剂进行归纳,并综述该通路抑制剂的联合用药策略,以期为不同亚型乳腺癌提供个体化靶向治疗方案。 相似文献
106.
ObjectiveDiabetic kidney disease (DKD) is the leading cause of death and disability of diabetes mellitus. However, there is still a lack of specific drugs for the treatment of DKD. The chief aim of this research is to investigate the role and mechanism of 2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione (DMDD) for DKD.MethodsWild type and TLR4 knockout mice were induced to diabetes. After 4-week treatment with DMDD, blood sugar, renal function, blood lipid and pathological changes were assessed. Real-time PCR, western blotting, and immunohistochemistry were employed to detect the expressions of TLR4, TGFβ1 and Smad2/3 in the renal tissue.ResultsDMDD improved the serum lipid and decreased fasting blood glucose levels in diabetic mice. CysC and urinary albumin levels increased markedly in the diabetic group, and they were obviously decreased after 4 weeks of DMDD treatment. Compared with the WT diabetic mice, the urinary albumin and CysC in the TLR4-/- mice were expressed at lower levels. HE and Masson’s staining revealed that DMDD clearly ameliorated pathological changes and renal fibrosis. When TLR4 gene was knock out, the pathological was improved. Mechanistically, TLR4, TGF-β1 and Smad2/3 were obvious up-regulation in the renal tissues of diabetic mice. The expressions of these proteins were significantly down-regulated after DMDD treatment (p < 0.05). In the TLR4-/- mice, mRNA and protein levels of TGF-β1 and Smad2/3 were obviously lower than those in the WT mice. In addition, IHC revealed that a strong in situ expressions of TLR4, TGF-β1 and Smad2/3 were seen in the kidney tissues of diabetic mice, which were distinctly weakened in the DMDD-treated mice. In the TLR4-/- mice, however, expressions of TGF-β1 and Smad2/3 were not remarkable increase in the diabetic mice compared with normal mice.ConclusionsThese results strongly indicate that TLR4 is essential for DMDD protection against renal dysfunction in diabetic mice. Its hypoglycemic and anti-fibrosis effects were likely mediated by the TLR4/TGFβ signaling pathway. 相似文献
107.
Maria M. Rubinstein MD David M. Hyman MD Imogen Caird BA Helen Won MS Krysten Soldan BSN Kenneth Seier MS Alexia Iasonos PhD William P. Tew MD Roisin E. O’Cearbhaill MD Rachel N. Grisham MD Martee L. Hensley MD Tiffany Troso-Sandoval MD Paul Sabbatini MD Joyce Guillen BS S. Duygu Selcuklu PhD Catherine Zimel BS Jean Torrisi MD Carol Aghajanian MD Vicky Makker MD 《Cancer》2020,126(6):1274-1282
108.
目的:研究PTPN6对前列腺癌细胞PC3的作用及其作用机制。方法:RT-PCR和Western blot实验检测前列腺癌组织和细胞以及癌旁组织和人前列腺上皮细胞中PTPN6的表达量;CCK-8和EDU染色实验检测PTPN6对前列腺癌细胞PC3增殖的影响;Western blot实验检测耐药相关蛋白P-gp和MRP-1的蛋白表达水平。结果:RT-PCR和Western blot结果显示,PTPN6在前列腺癌组织和细胞中的表达量显著低于癌旁组织和人前列腺上皮细胞中的表达量;过表达PTPN6显著抑制前列腺癌PC3细胞的增殖,并降低PC3细胞的耐药性;进一步的研究结果表明PTPN6可通过抑制SP1,并抑制p38 MAPK通路抑制PC3细胞的增殖和耐药。结论:PTPN6能够抑制前列腺癌细胞PC3的增殖和耐药,提高其化疗敏感性,作用机制是通过调控SP1/p38 MAPK信号通路来实现的,这一结果能够为临床上前列腺癌的诊断和治疗提供分子基础。 相似文献
109.
《Clinical Lymphoma, Myeloma & Leukemia》2020,20(8):e529-e541
IntroductionThe presence of FMS-like tyrosine kinase 3 (FLT3) internal tandem duplication (ITD) mutation in pediatric acute myeloid leukemia (AML) is associated with high rates of induction failure and worse survival. Its presence places the patient into a high-risk group. We aimed to describe the outcome of pediatric AML with FLT3-ITD mutation.Patients and MethodsWe performed a retrospective analysis of cases of AML from July 2007 till July 2017 at Children’s Cancer Hospital Egypt.ResultsSeventy-one patients had FLT3 gene mutation out of 687 patients with AML. Sixty-five patients had FLT3 gene mutation with allelic ratio > 0.4; 43 (66.1%) of 65 patients experienced complete remission (CR). Of the 43 patients, 16 patients maintained CR, 18 patients relapsed after first CR, 8 patients died, and 1 patient was lost to follow-up. Patients with relapsing disease died after salvage chemotherapy, except for one patient, who was alive after second CR. Allogeneic bone marrow transplantation (allo-BMT) was performed for 9 (13.8%) of 65 patients in first CR, of whom 8 were alive and in CR, and 1 patient experienced disease relapse and died. Seven patients (10.7%) were alive without allo-BMT. Three years’ overall and event-free survival for patients with FLT3-ITD mutation with high allelic ratio was 26.9% and 22.8%, respectively. Three years’ overall and event-free survival for patients treated with allo-BMT was 77.8% and 78.8%, respectively, versus patients treated without allo-BMT, 16.3% and 12.8%, respectively.ConclusionFLT3-ITD mutation in pediatric AML was associated with poor treatment outcomes, and the survival of relapsing patients was extremely poor. Allo-BMT in first remission was the best treatment option. Alternative donor transplants and FLT3 inhibitors are needed to improve outcome in developing countries. 相似文献
110.
Osteoarthritis (OA) is a progressive and degenerative joint disease. Aloin is a bitter and yellow-brown-coloured compound from the Aloe plant and is allowed for use in foods as a “natural flavour”. In our study, we examined the protective effects of Aloin on the inhibition of OA development as well as its underlying mechanism in both in vitro and vivo experiments. In in-vitro experiments, the protective effect of aloin on the anabolism and catabolism of the extracellular matrix (ECM) induced by IL-1 β in chondrocytes by inhibiting the expression of pro-inflammatory factors, including TNF-α (p = 0.016), IL-6 (p = 0.006), iNOS (p = 0.001) and COX-2 (p = 0.006). Mechanistically, Aloin suppressed the IL-1β-induced activation of the PI3K/Akt/NF-κB signalling pathway cascades. Moreover, molecular docking studies demonstrated that Aloin bound strongly to PI3K. In vivo, Aloin ameliorated the OA process in the destabilization of the medial meniscus (DMM) model.In summary, our findings demonstrate that Aloin ameliorates the progression of OA via the PI3K/Akt/NF-κB signalling pathways, which supports Aloin as a promising therapeutic agent for the treatment of OA. 相似文献