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91.
Mi Seon Kim Yunmi Lee Gi-Ho Sung Ji Hye Kim Jae Gwang Park Han Gyung Kim Kwang Soo Baek Jae Han Cho Jaegu Han Kang-Hyo Lee Sungyoul Hong Jong-Hoon Kim Jae Youl Cho 《Biomolecules & therapeutics.》2015,23(4):367-373
Cordyceps species including Cordyceps bassiana are a notable anti-cancer dietary supplement. Previously, we identified several compounds with anti-cancer activity from the butanol fraction (Cb-BF) of Cordyceps bassiana. To expand the structural value of Cb-BF-derived anti-cancer drugs, we employed various chemical moieties to produce a novel Cb-BF-derived chemical derivative, KTH-13-amine-monophenyl [4-isopropyl-2-(1-phenylethyl) aniline (KTH-13-AMP)], which we tested for anti-cancer activity. KTH-13-AMP suppressed the proliferation of MDA-MB-231, HeLa, and C6 glioma cells. KTH-13-AMP also dose-dependently induced morphological changes in C6 glioma cells and time-dependently increased the level of early apoptotic cells stained with annexin V-FITC. Furthermore, the levels of the active full-length forms of caspase-3 and caspase-9 were increased. In contrast, the levels of total forms of caspases-3, caspase-8, caspase-9, and Bcl-2 were decreased in KTH-13-AMP treated-cells. We also confirmed that the phosphorylation of STAT3, Src, and PI3K/p85, which is linked to cell survival, was diminished by treatment with KTH-13-AMP. Therefore, these results strongly suggest that this compound can be used to guide the development of an anti-cancer drug or serve as a lead compound in forming another strong anti-proliferative agent. 相似文献
92.
目的:通过调控Rab11在子宫颈癌HeLa细胞中的表达,观察Rab11对子宫颈癌HeLa细胞生物学功能的影响。方法将Rab11 siRNA转染至HeLa细胞,Western blot法检测Rab11蛋白表达变化,以转染阴性对照siRNA细胞为对照组,采用CCK8、克隆实验、EdU实验、Transwell小室法体外检测转染后的HeLa细胞增殖能力、侵袭能力的变化。结果与对照组比较,HeLa细胞转染Rab11 siRNA组Rab11蛋白表达明显下调(1.096±0.091比1.735±0.084,P<0.01)。与对照组比较,转染Rab11 siRNA组HeLa细胞增殖受抑制(吸光度值48 h:0.721±0.092比1.090±0.099;72 h:0.956±0.105比1.482±0.096;96 h:1.231±0.099比1.720±0.174,P<0.01),克隆形成数减少[(36±1)个比(75±8)个, P<0.01],增殖率降低[(33.880±1.902)%比(45.570±2.025)%,P<0.05]。Rab11 siRNA转染组较对照组侵袭率降低[(38.6±0.8)%比(100.0±0.2)%,P<0.01]。结论体外实验证实Rab11表达下调能够抑制HeLa细胞的生长。 相似文献
93.
Joo-Hui Han Yohan Kim Sang-Hyuk Jung Jung-Jin Lee Hyun-Soo Park Gyu-Yong Song Nguyen Manh Cuong Young Ho Kim Chang-Seon Myung 《The Korean journal of physiology & pharmacology》2015,19(5):421-426
The increased potential for vascular smooth muscle cell (VSMC) growth is a key abnormality in the development of atherosclerosis and post-angioplasty restenosis. Abnormally high activity of platelet-derived growth factor (PDGF) is believed to play a central role in the etiology of these pathophysiological situations. Here, we investigated the anti-proliferative effects and possible mechanism(s) of murrayafoline A, a carbazole alkaloid isolated from Glycosmis stenocarpa Guillamin (Rutaceae), on PDGF-BB-stimulated VSMCs. Murrayafoline A inhibited the PDGF-BB-stimulated proliferation of VSMCs in a concentration-dependent manner, as measured using a non-radioactive colorimetric WST-1 assay and direct cell counting. Furthermore, murrayafoline A suppressed the PDGF-BB-stimulated progression through G0/G1 to S phase of the cell cycle, as measured by [3H]-thymidine incorporation assay and cell cycle progression analysis. This anti-proliferative action of murrayafoline A, arresting cell cycle progression at G0/G1 phase in PDGF-BB-stimulated VSMCs, was mediated via down-regulation of the expression of cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, and proliferating cell nuclear antigen (PCNA), and the phosphorylation of retinoblastoma protein (pRb). These results indicate that murrayafoline A may be useful in preventing the progression of vascular complications such as restenosis after percutaneous transluminal coronary angioplasty and atherosclerosis. 相似文献
94.
Lyu C.Hou Z.-H.Wei Y.-B.Feng J.-H.Di Y. 《中国药理学通报》2015,(12):1652-1655
RAGE (receptor for advanced glycation end products) is a multiligand receptor on the cell surface. Ligand-RAGE interactions activate several signal transduction pathways that propagate cellular oxidative stress and inflammatory response. RAGE expressed on the CD4+ T cells has been identified as a central transduction receptor which affects the activation, proliferation, migration and differentiation of the cells. In addition, blockade of RAGE suppressed the development of multiple immune-related disorders mediated by CD4+ T cells. These studies highlight the importance of RAGE and its ligands for CD4+ T cells. This article briefly reviews the role of RAGE and its ligands on the proliferation, migration and differentiation of CD4+ T cells and summarizes the related research progress. 相似文献
95.
目的探讨环耙明阻断Hedgehog信号通路对肝癌细胞HepG2.2.15增殖的影响。方法培养肝癌细胞HepG2.2.15,用5μmol/L、15μmol/L、25μmol/L环耙明处理HepG2.2.15细胞24h、48h、72h,采用MTT检测环耙明对细胞活力的影响;EDU法检测细胞DNA合成情况;Real-timePCR法检测细胞Gli1的表达情况。结果用5μmol/L、15μmol/L、25μmol/L浓度的环耙明处理HepG2.2.15细胞24h、48h、72h后,MTT检测结果显示细胞活力降低,较空白组差异明显(P<0.05);EDU法检测结果显示25μmol/L的环耙明作用于细胞不同时间后,HepG2.2.15细胞的DNA合成率下降,与空白组相比差异有统计学意义(P<0.01);Real-time PCR法实验结果显示5μmol/L、15μmol/L、25μmol/L浓度的环耙明处理组与对照组相比,Gli1表达水平明显降低(P<0.05)。结论不同浓度环耙明能抑制HepG2.2.15细胞的增殖,减少HepG2.2.15细胞的DNA合成率;其作用机制可能与HepG2.2.15细胞中Gli1、mRNA的表达水平下降有关。 相似文献
96.
Litle VR Leavenworth JD Darragh TM Kosinski LA Moore DH Smith-McCune KK Warren RS Palefsky JM Welton ML 《Diseases of the colon and rectum》2000,43(3):346-352
PURPOSE: Management of anal high-grade squamous intraepithelial lesions is controversial. Anal and cervical high-grade squamous intraepithelial lesions are similar in that they occur in transitional squamous epithelium, are associated with human papilloma virus infection, and have increased incidence in the immunocompromised population. Ablation of cervical high-grade squamous intraepithelial lesions is preferred, but similar ablation or excision of anal high-grade squamous intraepithelial lesions may compromise bowel control; thus, there is a need to define the malignant potential of anal high-grade squamous intraepithelial lesions. METHODS: We analyzed 50 paraffin sections of normal anoderm, anal low-grade squamous intraepithelial lesions, high-grade squamous intraepithelial lesions, and anal squamous-cell carcinoma. Microvessels were detected immunohistochemically with von Willebrand factor and counted manually along the epithelial-stromal junction. Proliferation and apoptosis were determined in the epithelial cells with MIB-1 antibody immunostaining and the terminal deoxynucleotidyl transferase-mediated digoxigenin-11-dUTP nick end labeling, respectively. RESULTS: Microvascular density was significantly greater in anal high-grade squamous intraepithelial lesions (mean, 0.50 vessels/cm)vs. normal anoderm (mean, 0.21 vessels/cm;P=0.0017, Mann-WhitneyU test). The proliferative percentages were greater in low-grade squamous intraepithelial lesions, high-grade squamous intraepithelial lesions, and squamous-cell carcinoma (mean, 20.4, 21.8, and 23.6 percent)vs. normal anoderm (mean, 14.4 percent), although not significantly (P=0.06, Kruskal-Wallis statistic). Although the mean proliferative proportions were similar in low-grade squamous intraepithelial lesions and high-grade squamous intraepithelial lesions, the apoptotic proportion was lower for high-grade squamous intraepithelial lesions than low-grade squamous intraepithelial lesions (10.13vs. 19.96 percent, respectively;P=NS, Mann-WhitneyU test). CONCLUSIONS: Angiogenesis, increased proliferation, and decreased apoptosis occur in anal high-grade squamous intraepithelial lesions as they do in the cervix before the development of malignancy. These biologic markers support the importance of anal high-grade squamous intraepithelial lesions as a potential premalignant lesion warranting surgical intervention.Supported by a grant from the National Institutes of Health (DDDN, NIDDK KO8 DK 02507-03).Podium presentation at The American Society of Colon And Rectal Surgeons' 100th Anniversary and Tripartite Meeting, Washington, D.C., May 1 to 6, 1999. 相似文献
97.
《Lung cancer (Amsterdam, Netherlands)》2015,88(3):258-264
ObjectivesNicotine and its associated nicotinic acetylcholine receptors (nAChRs) are believed to be involved in the progression of lung carcinomas. This study aimed at examining the localization of nAChRs in human lung tumours and, by using primary cultures of tumour cells derived from these tumours, determining the nAChR roles in cell proliferation and tumour invasion.Materials and methodsImmunohistochemistry was used to assess nAChR expression in non-small cell lung carcinomas (NSCLC). Primary cultures of tumour cells were established from NSCLC tissue samples and the effects of nicotine and nAChR antagonists on cell proliferation and invasion were assessed.Resultsα5, α7, β2 and β4 nAChR subunits were expressed in all adenocarcinomas (AC) and squamous cell carcinomas (SCC) tissue samples. In AC, all subunits were identified in glandular structures. In SCC, α5, β2 and β4 subunits were essentially identified in tumour cells at invasive fronts, whereas α7 subunit was mainly present in the most differentiated tumour cells and less frequently at invasive fronts. In AC and SCC, there was an inverse distribution of cell proliferation marker Ki-67 and α7 nAChR. Both α7 nAChR and heteromeric nAChRs positively regulated in vitro tumour invasion in NSCLC. Heteromeric nAChRs had a limited activity in regulating tumour cell proliferation in vitro. In contrast, α7 nAChR was a repressor of proliferation in tumour cells isolated from well differentiated NSCLC but mediated the pro-proliferative activity of nicotine in cells isolated from poorly differentiated NSCLC.Conclusionα7 nAChR and heteromeric α5*β2*β4* nAChRs play a role in ex vivo tumour progression by stimulating invasion and, depending on the differentiation status of the tumour, by regulating proliferation. Our results suggest that the use of α7 nAChR antagonists to prevent lung cancer progression should be restricted to poorly differentiated tumours. 相似文献
98.
Wei Li Ying Zhou Jin Yang Xu Zhang Huanhuan Zhang Ting Zhang Shaolin Zhao Ping Zheng Juan Huo Huiyi Wu 《Journal of experimental & clinical cancer research : CR》2015,34(1)
Background
Bone marrow mesenchymal stem cells (BM-MSCs) have been identified to be closely associated with tumor growth and progression. However, the roles of tumor-resident MSCs in cancer have not been thoroughly clarified. This study was to investigate the regulating effect of gastric cancer-derived MSCs (GC-MSCs) on gastric cancer and elucidate the underlying mechanism.Methods
GC-MSCs were isolated from primary human gastric cancer tissues and characterized. The effect of GC-MSCs on gastric cancer cell proliferation was analyzed by MTT assay and colony formation assay. Transwell migration assay was performed to evaluate the influence of GC-MSCs in gastric cancer cell migration. The regulating effects of interactions between gastric cancer cells and GC-MSCs on their pro-angiogenic abilities were analyzed in a co-culture system, with the expression, and secretion of pro-angiogenic factors detected by RT-PCR and Luminex assay. Tube formation assay was used to further validate the angiogenic capability of gastric cancer cells or GC-MSCs. Cytokine profiles in the supernatant of GC-MSCs were screened by Luminex assay and neutralizing antibody was used to identify the key effective cytokines. The activations of Akt and Erk1/2 in gastric caner cells were detected by Western blot.Results
GC-MSC treatment enhanced the proliferation and migration of BGC-823 and MKN-28 cells, which was more potently than MSCs from adjacent non-cancerous tissues (GCN-MSCs) or bone marrow (BM-MSCs). Higher expression levels of pro-angiogenic factors were detected in GC-MSCs than GCN-MSCs or BM-MSCs. After 10 % GC-MSC-CM treatment, BGC-823, and MKN-28 cells expressed increased levels of pro-angiogenic factors and facilitated tube formation more potently than cancer cells alone. Furthermore, GC-MSCs produced an extremely higher level of interleukin-8 (IL-8) than GCN-MSCs or BM-MSCs. Blockade of IL-8 by neutralizing antibody significantly attenuated the tumor-promoting effect of GC-MSCs. In addition, 10 % CM of IL-8-secreted GC-MSCs induced the activations of Akt or Erk1/2 pathway in BGC-823 and MKN-28 cells.Conclusion
Tumor-resident GC-MSCs promote gastric cancer growth and progression more efficiently than GCN-MSCs or BM-MSCs through a considerable secretion of IL-8, which could be a possible target for gastric cancer therapy. 相似文献99.
100.
目的初步探讨消幻汤含药血清对人神经母细胞瘤细胞SH—SYSY的增殖及形态的影响。方法通过连续7d给家兔灌胃给药,制备消幻汤含药兔血清、利培酮含药免血清及空白兔血清。将上述血清作用于SH—sY5Y细胞24~72h,通过倒置显微镜观察舍药血清干预48h的SH—SY5Y细胞的形态,并且每24小时采用MTT法检测SH~SY5Y细胞的增殖情况。结果消幻汤含药血清处理48h的SH—SY5Y细胞突起较长,细胞间接触紧密,并且伸出伪足,虽表现为增殖旺盛,但消幻汤含药血清对SH—SY5Y细胞的增殖与空白血清相比,差异无统计学意义(P〉0.05),而利培酮含药血清则可显著增加sH—SY5Y的细胞数量,呈现对数增殖趋势,与其他各组比较,差异有统计学意义(P〈0.05)。结论消幻汤含药血清对SH—SY5Y细胞的正常形态有促进作用,而对SH—SY5Y细胞的正常增殖无显著干预作用,与利培酮舍药血清作用不同。 相似文献