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1.
Current study was aimed to investigate the effect of dihydromyricetin on hydrogen peroxide induced oxidative stress in the osteosarcoma cells. MTT assay showed that hydrogen peroxide treatment at a concentration of 100 μM caused a significant (p < 0.005) reduction in the viability of MG63 cells. However, reduction in cell viability caused by 100 μM concentration of hydrogen peroxide was completely prevented on incubation with 30 μM dose of dihydromyricetin. Treatment with 100 μM concentration of hydrogen peroxide for 24 h led to condensation of chromatin material, rounding of cell shape and detachment of cells. The results from flow cytometry using annexin V-FITC and PI double staining showed apoptosis induction in 47.84 ± 5.21% cells on treatment with 100 μM concentration of hydrogen peroxide compared to 2.32 ± 0.54% in controlcells. The apoptotic alterations in MG63 cell morphology were prevented significantly on pre-treatment with 30 μM doses of dihydromyricetin for 48 h. Annexin V-FITC and PI staining showed reduction of hydrogen peroxide induced apoptotic cell percentage to 3.07 ± 0.86% on pre-treatment of MG63 cells with 30 μM dose of dihydromyricetin. Western blot analysis showed a significant increase in the activation of caspase-3 and -9 on treatment of MG63 cells for 24 h with 100 μM concentration of hydrogen peroxide. The expression level of Bcl-2 was decreased significantly by 100 μM concentration of hydrogen peroxide in MG63 cells. However, pre-treatment of MG63 cells with 30 μM dose of dihydromyricetin for 48 h significantly prevented hydrogen peroxide induced increase in caspase-3 and -9 levels and reduction in Bcl-2 level. Thus dihydromyricetin prevents hydrogen peroxide induced reduction in viability and induction of apoptosis in MG63 cells through down-regulation of caspase activation and up-regulation of Bcl-2 levels.  相似文献   
2.
目的:探讨癌基因Src在体外培养骨肉瘤细胞侵袭伪足形成中的作用。方法:构建Src sh RNA慢病毒表达载体,在HEK293T细胞中包装慢病毒,感染HT-1080骨肉瘤细胞,经嘌呤霉素加压筛选,获得稳定沉默Src基因的骨肉瘤细胞系HT-1080-sh Src;实时定量PCR和Western Blot法检测基因沉默效率;采用原位明胶酶谱法检测侵袭伪足形成;采用侵袭小室实验检测下调Src基因表达对HT-1080细胞侵袭力的影响。结果:成功构建稳定沉默Src基因的骨肉瘤细胞系HT-1080-sh Src及对照细胞系HT-1080-shluc,经实时定量PCR和Western Blot检测,与对照细胞系相比,HT-1080-sh Src细胞中Src基因表达下调3倍以上;下调HT-1080细胞中Src基因表达能显著抑制HT-1080细胞侵袭伪足形成及其对细胞外基质的降解能力;下调Src基因表达能显著抑制骨肉瘤细胞侵袭力。结论:癌基因Src参与调节骨肉瘤细胞HT-1080侵袭伪足形成,促进肿瘤侵袭、转移。  相似文献   
3.
目的:探寻一种有效地从骨肉瘤患者外周血中富集并鉴定循环肿瘤细胞的方法。方法:利用基于物理过滤与原位杂交结合的技术对骨肉瘤患者外周血循环肿瘤细胞分离并鉴定。采用直径8μm纳米滤膜截留外周血中体积较大的白细胞及肿瘤细胞,利用多重RNA原位杂交技术检测CD45、EpCAM、CK8、CK18、CK19、vimentin及twist基因表达,并根据结果对滤膜截留下的细胞进行鉴定并分型。结果:本研究所使用的基于物理过滤与原位杂交技术的循环肿瘤细胞检测方法可以高效地从骨肉瘤患者外周血中富集骨肉瘤循环肿瘤细胞,该方法富集细胞的效率超过90%。15例健康志愿者中1例志愿者检测结果阳性。20例纳入研究的骨肉瘤患者中19例患者外周血中检测出CTC,CTC计数范围为0-20。肿瘤转移患者外周血CTC计数为11.33±5.88,肿瘤未转移患者外周血CTC计数为4.36±2.98,差异具有统计学意义(P=0.0022)。肿瘤转移患者外周血间质型CTC比例高于肿瘤未转移患者(P=0.0031)。结论:利用基于物理过滤与原位杂交结合的技术可以有效地检测骨肉瘤患者外周血循环肿瘤细胞。CTC检测结果可以作为辅助判断肿瘤转移情况的辅助指标。  相似文献   
4.
Osteosarcoma, the most common type of primary bone cancer, is the second highest cause of cancer-related death in pediatric patients. To understand the mechanisms behind osteosarcoma progression and to discover novel therapeutic strategies for this disease, a reliable and appropriate mouse model is essential. For this purpose, osteosarcoma cells need to be injected into the bone marrow. Previously, the intratibial and intrafemoral injection methods were reported; however, the major drawback of these methods is the potential leakage of tumor cells from the injection site during or after these procedures. To overcome this, we have established an improved method to minimize leakage in an orthotopic mouse model of osteosarcoma. By taking advantage of the anatomical benefits of the femur with less bowing and larger medullary cavity than those of the tibia, osteosarcoma cells are injected directly into the femoral cavity following reaming of its intramedullary space. To prevent potential leakage of tumor cells during and after the surgery, the injection site is sealed with bone wax. This method requires a minor surgery of approximately 15 min under anesthesia. Our established orthotopic osteosarcoma model could serve as a valuable and reliable tool for examining progression of various types of bone tumors.  相似文献   
5.
目的:将合成的两种量子点应用于研究人骨肉瘤HOS细胞系,初步检测其生物毒性,以确定本研究所制备量子点可否应用于骨肉瘤的基础研究。方法:将生长良好的HOS细胞与制备的两种量子点分别共培养,使用MTT试剂盒检测不同时间点细胞活性,实验进行三次,取其平均值,分析所得数据,并绘制出量子点浓度-细胞活性曲线,分析得出两者之间的量效关系。结果:1.4μM的CdTe/ZnS QDs和0.275μM的Cd Te/Cd S QDs分别是本实验中对HOS细胞的最高毒性浓度。较短时间(30 min)的暴露分别导致了48.6±0.9%和31.9±0.8%的细胞死亡,3 h后分别有33.7±2.3%和49.4±1.1%的细胞存活。而在孵育了18 h之后,只有28.0±1.6%和15.3±1.6%的细胞存活。我们可以观察到均为典型的时间/浓度曲线。结论:选用适宜浓度以及共培养时间,本实验制备的量子点完全可以满足纳米量子点粒子使用于HOS细胞研究的基本生物学条件,可以进行人骨肉瘤HOS细胞测温等的一些列实验操作。由于量子点自身优越的光学性能以及可接受的生物安全性,在肿瘤研究领域具有很大的潜力,将会成为肿瘤示踪、检测、以及靶向治疗新的有力工具。  相似文献   
6.
Circular RNAs (circRNAs) have recently shown capabilities as gene regulators in mammals. Some of them interact with microRNAs (miRNAs) and function as sponges to affect related miRNAs' activities. In this study, the molecular function of circRNA_0009910 and its potential downstream miRNA targets were explored. The expression levels of hsa_circ_0009910 were found to be overexpressed in osteosarcoma (OS) cells. Knockdown of circ_0009910 induced cell proliferation inhibition, cell cycle arrest, and apoptosis in OS cells. The target miRNA was predicted to be miR-449a, whose expression was downregulated in OS cells. Inhibition of miR-449a abolished the effect of circ_0009910 knockdown on cell growth and apoptosis. The expression of miR-449a were found to be negatively correlated with that of circ_0009910 in OS tissues. Direct interaction of circ_0009910 and miR-449a was confirmed through dual-luciferase assays. Moreover, IL6R was predicted as a potential target of miR-449a. Overexpression of miR-449a decreased the mRNA and protein levels of IL6R. Restoration of IL6R impaired the miR-449a induced inhibition of cell proliferation, cell cycle arrest, and apoptosis. The mRNA expression of IL6R was inversely correlated with miR-449a in OS tissues. In addition, JAK1/STAT3 signaling pathway was regulated by circ_0009910/miR-449a/IL6R axis. Taken together, we suggested that circ_0009910 acted as a sponge of miR-449a and upregulated miR-449a functional target IL6R, thereby contributed to carcinogenesis of OS.  相似文献   
7.
目的研究Sox2在临床骨肉瘤标本中表达,并探讨其表达与肿瘤的生物学特征及临床预后的关系。方法采用免疫组织化学Maxvision检测Sox2蛋白在54例人骨肉瘤标本的表达,12例骨化性肌炎作为正常对照。结果骨肉瘤标本中Sox2阳性表达率为20.69%(12/58),而在骨化性肌炎中Sox2阳性表达率为0%(0/12),Sox2在骨肉瘤标本中的阳性率显著高于对照组骨化性肌炎(P0.01)。Sox2的表达与骨肉瘤临床Enneking分期有关(P0.05),与患者的年龄、性别、部位、组织学类型等其它临床病理因素无关(P0.05)。结论 Sox2可能在骨肉瘤的发生、发展和转移中发挥重要作用,提示Sox2的表达可考虑作为骨肉瘤临床评价生物学行为及判断预后的指标之一。  相似文献   
8.
Osteosarcoma chemotherapy has improved survival rates, however, chemoresistance and drug toxicity still limit therapy. Drug combinations may overcome these limitations by allowing fewer chemoresistant cells to survive. The aim of this study was to evaluate the cytotoxic potential of hesperetin to osteosarcoma and to analyze the cell cycle effects of combinations of hesperetin with chemotherapeutic agents. For this, the U2OS human osteosarcoma cell line was exposed to hesperetin or hesperetin combined with etoposide or doxorubicin in defined proportions. Hesperetin was less cytotoxic compared to chemotherapeutic agents, as shown by cell growth, viability and clonogenic assays. Notwithstanding, hesperetin combined with etoposide showed additive effects on the inhibition of cell growth. Furthermore, hesperetin induced G2-phase arrest, associated with decreased gene expression of cyclins B1 and E1 and cyclin-dependent kinases 1 and 2. The combination with higher additive effect resulted in higher percentage of cells in G2-phase, showing that G2-phase arrest is associated with cytotoxicity. Moreover, hesperetin induced cytostatic effects. In conclusion, our results suggest that G2-phase arrest is an important step for hesperetin-induced cytotoxicity in U2OS cells. Hesperetin shows potential cytotoxicity when combined with etoposide, which may have implications on therapeutic developments for osteosarcoma.  相似文献   
9.
应用鸡胚绒毛尿囊膜模型(chick embryo chorioallantoic membrane,CAM),观察人骨肉瘤OS-732细胞系诱导血管生成过程及血管生长相关因子的表达。结果显示,本细胞系具有较强的促血管生成能力并表达血管内皮生长因子(vacular endothelial growth factor,VEGF),碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF0,鸡胚绒毛尿囊膜OS-732细胞系接种瘤细胞中血管内皮生长因子(VEGF),转化生长因子β1(Transforming growth factor,TGF-β1)均呈阳性表达,而且VEGF呈持续高表达,结果表明VEGF,bFGF、TGF-β1可能共同参与骨肉瘤OS-732细胞系诱导的血管生成,而VEGF可能起着主要作用,提示阻断VEGF的作用可能影响骨肉瘤OS-732细胞系诱导的血管生成,此研究为以VEGF为靶点进行抗血管生成实验提供了依据。  相似文献   
10.
AimsChondrosarcoma, osteosarcoma and Ewing sarcoma form the majority of malignant primary tumours of bone. High-grade bone sarcomas require intensive treatment due to their rapid and invasive growth pattern and metastasising capabilities. This nationwide study covers overall incidence, treatment and survival patterns of bone sarcomas in a 15-year period (2000–2014) in the total population of the Netherlands.Patients and methodsData for this study were derived from the Netherlands Cancer Registry, which receives primary notification from the national pathology database. Classification and categorisation was based on the ICD-O-3 classification and the WHO classification 2013 applied according to our clinicopathological expertise. Overall incidence over the 15-year-period was calculated as a rate per 100,000 person-years (using the European Standardised Rate, ESR). Survival was analysed with Kaplan-Meier curves and Cox proportional hazards regression.ResultsIncidence for high-grade chondrosarcoma (n = 429) was estimated at 0.15 per 100,000 ESR, and 5-year overall survival at 65.9% (95% confidence interval (CI): 61.0%–70.4%). Incidence for high-grade central osteosarcoma (n = 605) was estimated at 0.25 per 100,000 ESR and 5-year survival at 53.9% (95%CI: 49.7%–58.0%). Ewing sarcoma incidence (n = 334) was estimated at 0.15 per 100,000 ESR and 5-year survival at 59.3% (95%CI: 53.5%–64.6%). For high-grade central osteosarcoma, treatment at a bone tumour centre was associated with better survival (HR 0.593).ConclusionsThis study provides comprehensive incidence estimates for all the main primary bone sarcomas over a 15-year time period in a Northern European country with little migration. Centralisation of bone sarcoma care improves the clinical outcome in osteosarcoma.  相似文献   
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