Science.gov

Sample records for osteosarcoma mg-63 cells

  1. Aberrant tropoelastin secretion in MG-63 human osteosarcoma cells

    SciTech Connect

    Curtiss, S.W.

    1989-01-01

    The secretion of newly synthesized tropoelastin, the soluble precursor of the extracellular matrix protein elastin, is not well understood. MG-63 human osteosarcoma cells were found by immunoblot analysis to synthesize 62 kD and 64 kD tropoelastins. Media from 63 cells labelled for five hours with ({sup 3}H)-valine contain no detectable tropoelastin, unlike media from other tropoelastin-synthesizing cells. Immunoblots of conditioned media and 1Ox-concentrated conditioned media left on the cells for six days also show an absence of tropoelastin from the cell media. No insoluble elastin is associated with the cell layer, as determined by amino acid analysis and electron microscopy of 18-21 day cell cultures. The absence of tropoelastin from the cell medium and elastin from the extracellular matrix indicates that MG63 cells do not secrete tropoelastin as expected, but accumulate it intracellularly. This accumulation is transient: immunoblots and immunofluorescence microscopy show that cells three days after passage have the highest steady-state levels of tropoelastin per cell, that day 8 cells contain lower but still significant amounts of tropoelastin, and that by day 22 tropoelastin is no longer present in the cell cultures. Cell density is a critical factor in the observed pattern of tropoelastin expression. Cells seeded at ten fold their usual initial density have high tropoelastin levels at one day after passage, sooner than cells seeded normally. Tropoelastin also disappears from high density-seeded cells more quickly and is no longer detectable at day 10. Lysosome-like vesicles containing membranous structures appear by immunoelectron microscopy to be the primary site of intracellular tropoelastin localization.

  2. p53 mediated apoptosis in osteosarcoma MG-63 cells by inhibition of FANCD2 gene expression

    PubMed Central

    Xia, Peng; Sun, Yifu; Zheng, Changjun; Hou, Tingting; Kang, Mingyang; Yang, Xiaoyu

    2015-01-01

    Purpose: The aim of this study was to investigate the association between osteosarcoma (OS) and Fanconi anemia (FA) related pathways and the molecular mechanisms. Methods: siRNA for Fanconi anemia complementation group D2 (FANCD2) was constructed and transfected into the osteosarcoma cell line MG-63 cells. Expression of TP53INP1, p53, p21, caspase-9, and caspase-3 mRNA in MG-63 cells were examined by real-time fluorescence quantitative PCR, and the protein levels were also determined by western blot. Results: After silence of the FANCD2 gene in MG-63 cells, cell proliferation was inhibited, cell cycle was arrested and cell apoptosis was induced. The apoptosis was mediated by the p53 signaling pathway. After FANCD2 expression was inhibited, TP53INP1 gene expression was up-regulated, phosphorylation of p53 was promoted and the p21 protein was activated, leading to cell cycle arrested in G1, finally resulted in caspase-dependent cell apoptosis. Conclusions: Inhibition of FANCD2 gene expression can induce apoptosis of osteosarcoma cells, which indicated that FANCD2 played an important role in the development of osteosarcoma and it might be a potential target for treatment of osteosarcoma. PMID:26379910

  3. Emodin mitigates the oxidative stress induced by cisplatin in osteosarcoma MG63 cells

    PubMed Central

    Yan, Li; Hu, Rui; Tu, Song; Cheng, Wen-Jun; Zheng, Qiong; Wang, Jun-Wen; Kan, Wu-Sheng; Ren, Yi-Jun

    2016-01-01

    Previously, the application of cisplatin in chemotherapy was limited due to the significant side effects on normal cell growth. In the present study, the concomitant application of emodin with cisplatin was demonstrated to ameliorate cisplatin-induced oxidative stress and markedly suppress tumor cell proliferation for the first time. Human osteosarcoma MG-63 cells were treated with cisplatin alone or in combination with emodin. The cell viability was determined by MTS assays and the augmentation of reactive oxygen species were determined by fluorogenic probes; in addition, a stable MG-63 subline bearing antioxidant response element (ARE)-driven luciferase expression was developed to monitor the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)-ARE signaling pathway. The results indicated that cisplatin or emodin may inhibit MG-63 cell proliferation in a time- or dose-dependent manner, respectively. Concomitant treatment with cisplatin and emodin demonstrated synergic anti-tumor effects. Cisplatin augmented reactive oxygen species in the MG-63 cells, followed by the translocation of Nrf2 from the cytoplasm into the nucleus, which triggered ARE-driven luciferase expression. The addition of emodin diminished the previously described phenomenon, resulting in decreased ROS augmentation, translocation of Nrf2 and ARE-driven luciferase activity. In conclusion, emodin could ameliorate cisplatin-induced oxidative stress and protect the cells from oxidative stress-induced damage. The findings of the present study provide a novel strategy for the treatment of osteosarcoma using emodin and cisplatin. PMID:27602124

  4. Effects of indomethacin, nimesulide, and diclofenac on human MG-63 osteosarcoma cell line.

    PubMed

    Díaz-Rodríguez, Lourdes; García-Martínez, Olga; Morales, Manuel Arroyo-; Rodríguez-Pérez, Laura; Rubio-Ruiz, Belén; Ruiz, Concepción

    2012-01-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most widely prescribed drugs worldwide and serve as treatment of some degenerative inflammatory joint diseases. The aim of the present study was to investigate the influence of different concentrations of three NSAIDs on cell proliferation, differentiation, antigenic profile, and cell cycle in the human MG-63 osteosarcoma cell line, incubated for 24 hr. All NSAIDs had an inhibiting effect on osteoblastic proliferation. Treatments for 24 hr had small but significant effects on the antigenic profile. No treatment altered osteocalcin synthesis. Indomethacin and nimesulide treatments arrested the cell cycle at G(0)/G(1). These results suggest that indomethacin, nimesulide, and diclofenac appear to have no effects on osteocalcin synthesis and a slight effect on the antigenic profile. They may delay bone regeneration due to their inhibiting effect on osteoblast growth. Therefore, these drugs should only be used in situations that do not require rapid bone healing. PMID:21385796

  5. Paracrine-mediated osteoclastogenesis by the osteosarcoma MG63 cell line: is RANKL/RANK signalling really important?

    PubMed

    Costa-Rodrigues, J; Teixeira, C A; Fernandes, M H

    2011-08-01

    Although in the past little attention has been paid to the influence of osteosarcoma cells in osteoclast function, recent studies suggest a close relationship between osteosarcoma aggressiveness and osteoclastic activity. The present study addresses the paracrine effects of MG63 cells, a human osteosarcoma-derived cell line, on the differentiation of peripheral blood osteoclast precursor cells (PBMC). PBMC were cultured for 21 days in the presence of conditioned media from MG63 cell cultures (CM) collected at 48 h (CM_MG1), 7 days (CM_MG2) and 14 days (CM_MG3). MG63 cell cultures displayed the expression of ALP and BMP-2 and, also, the osteoclastogenic genes M-CSF and RANKL, although with a low expression of RANKL. PBMC cultures supplemented with CM presented an evident osteoclastogenic behavior, which was dependent on the culture period of the MG63 cells. The inductive effect appeared to be more relevant for the differentiation and activation genes, c-myc and c-src, and lower for genes associated with osteoclast function. In addition, PBMC cultures displayed increased functional parameters, including calcium phosphate resorbing activity. Assessment of the PBMC cultures in the presence of U0126, PDTC, and indomethacin suggested that in addition to MEK and NFkB pathways, other signaling mechanisms, probably not involving RANKL/RANK interaction, might be activated in the presence of conditioned medium from MG63. In conclusion, MG63 cell line appears to induce a significant paracrine-mediated osteoclastogenic response. Understanding the mechanisms underlying the interaction of osteosarcoma cells and osteoclasts may contribute to the development of new potential approaches in the treatment of such bone metabolic diseases. PMID:21479680

  6. Characterization of Notch Signaling During Osteogenic Differentiation in Human Osteosarcoma Cell Line MG63.

    PubMed

    Ongaro, Alessia; Pellati, Agnese; Bagheri, Leila; Rizzo, Paola; Caliceti, Cristiana; Massari, Leo; De Mattei, Monica

    2016-12-01

    Osteogenic differentiation is a multi-step process controlled by a complex molecular framework. Notch is an evolutionarily conserved intercellular signaling pathway playing a prominent role in cell fate and differentiation, although the mechanisms by which this pathway regulates osteogenesis remain controversial. This study aimed to investigate, in vitro, the involvement of Notch pathway during all the developmental stages of osteogenic differentiation in human osteosarcoma cell line MG63. Cells were cultured in basal condition (control) and in osteoinductive medium (OM). Notch inhibitors were also added in OM to block Notch pathway. During osteogenic differentiation, early (alkaline phosphatase activity and collagen type I) and late osteogenic markers (osteocalcin levels and matrix mineralization), as well as the gene expression of the main osteogenic transcription factors (Runx2, Osterix, and Dlx5) increased. Time dependent changes in the expression of specific Notch receptors were identified in OM versus control with a significant reduction in the expression of Notch1 and Notch3 receptors in the early phase of differentiation, and an increase of Notch2 and Notch4 receptors in the late phase. Among Notch nuclear target genes, Hey1 expression was significantly higher in OM than control, while Hes5 expression decreased. Osteogenic markers were reduced and Hey1 was significantly inhibited by Notch inhibitors, suggesting a role for Notch through the canonical pathway. In conclusion, Notch pathway might be involved with a dual role in osteogenesis of MG63, through the activation of Notch2, Notch4, and Hey1, inducing osteoblast differentiation and the depression of Notch1, Notch3, and Hes5, maintaining an undifferentiated status. J. Cell. Physiol. 231: 2652-2663, 2016. © 2016 Wiley Periodicals, Inc. PMID:26946465

  7. Baicalein suppresses the viability of MG-63 osteosarcoma cells through inhibiting c-MYC expression via Wnt signaling pathway.

    PubMed

    He, Nengbin; Zhang, Zhichang

    2015-07-01

    The major reason responsible for the poor prognosis of osteosarcoma is the malignant proliferation of osteosarcoma cells. The activated Wnt/β-catenin signaling induces c-MYC gene transcription and results in osteocytes' carcinomatous change, which contributes to osteosarcoma development, so c-MYC gene is one of the therapeutic targets. The role of multiple botanical extracts in the expression of β-catenin's target gene c-MYC in osteosarcoma MG-63 cells was tested by cellomics high content screening. Baicalein was identified as the most effective one which can inhibit the proliferation and promote the apoptosis of MG-63 cells in a dose-dependent manner by cell counting kit-8 test and fluorescence-activated cell sorting, respectively. This process was associated with the decreased levels of β-catenin and its target gene c-MYC, identified by q-PCR and Western blotting, respectively. When MG-63 cells were treated with both baicalein and JNK inhibitor SP600125, the apoptosis and expression of c-MYC were not significantly decreased. After the construct pcDNA3.1-BANCR (BRAF-regulated lncRNA 1) was transfected into MG-63 cells, RT-PCR, Western blotting and CCK-8 assay showed that BANCR was positively correlated with baicalein. These results indicated that baicalein inhibited osteosarcoma cell proliferation and promoted apoptosis by targeting c-MYC gene through Wnt signaling, in which JNK and BANCR were also involved as well as β-catenin, suggesting a new potential mechanism for us to better understand the inhibiting effect of baicalein on osteosarcoma. PMID:25893737

  8. Sulforaphane induces DNA damage and mitotic abnormalities in human osteosarcoma MG-63 cells: correlation with cell cycle arrest and apoptosis.

    PubMed

    Ferreira de Oliveira, José Miguel P; Remédios, Catarina; Oliveira, Helena; Pinto, Pedro; Pinho, Francisco; Pinho, Sónia; Costa, Maria; Santos, Conceição

    2014-01-01

    Osteosarcoma is a recalcitrant bone malignancy with poor responsiveness to treatments; therefore, new chemotherapeutic compounds are needed. Sulforaphane (SFN) has been considered a promising chemotherapeutic compound for several types of tumors by inducing apoptosis and cytostasis, but its effects (e.g., genotoxicity) in osteosarcoma cells remains exploratory. In this work, the MG-63 osteosarcoma cell line was exposed to SFN up to 20 μM for 24 and 48 h. SFN induced G2/M phase arrest and decreased nuclear division index, associated with disruption of cytoskeletal organization. Noteworthy, SFN induced a transcriptome response supportive of G2/M phase arrest, namely a decrease in Chk1- and Cdc25C-encoding transcripts, and an increase in Cdk1-encoding transcripts. After 48-h exposure, SFN at a dietary concentration (5 μM) contributed to genomic instability in the MG-63 cells as confirmed by increased number of DNA breaks, clastogenicity, and nuclear and mitotic abnormalities. The increased formation of nucleoplasmic bridges, micronuclei, and apoptotic cells positively correlated with loss of viability. These results suggest that genotoxic damage is an important step for SFN-induced cytotoxicity in MG-63 cells. In conclusion, SFN shows potential to induce genotoxic damage at low concentrations and such potential deserves further investigation in other tumor cell types. PMID:24405297

  9. The synergistic anticancer effect of cisplatin combined with Oldenlandia diffusa in osteosarcoma MG-63 cell line in vitro

    PubMed Central

    Pu, Feifei; Chen, Fengxia; Lin, Song; Chen, Songfeng; Zhang, Zhicai; Wang, Baichuan; Shao, Zengwu

    2016-01-01

    Background Oldenlandia diffusa (OD) is a well-known traditional Chinese medicine, which is used to prevent and treat many disorders, especially cancers. However, its role in osteosarcoma has not been well understood. Here, we used OD and cisplatin individually and combined in osteosarcoma MG-63 cell to explore whether OD could induce cellular apoptosis and suppress the ability of proliferation and invasion of osteosarcoma MG-63 cell. Methods The changes of cellular shape were analyzed by optical microscopy. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay was used to analyze cell survival rate in vitro. Flow cytometry was performed to detect cell cycle and cell death. Scratch migration assay was used to evaluate cell migration and invasion. Western blot was performed to determine the expression levels of pro-apoptotic and anti-apoptotic protein. Results In this study, we found that the survival rate reduced significantly in the combined group compared with the individual group and control group. The apoptosis-inducing effect of combined application was much more significant than that of individual application. The invasion ability of combined application was significantly lower than that of the individual application. In the combined group, there were high expression levels of pro-apoptotic protein and low expression of anti-apoptotic protein. Cell-cycle analysis showed a change in the cell-cycle distribution and arrested cells in G2-M phase. Conclusion In this study, we found that OD inhibited proliferation and induced apoptosis in the human osteosarcoma MG-63 cell line in a time-dependent and dose-dependent manner. In addition, OD displayed inhibitory activity on MG-63 cell proliferation and invasion and the study also showed that OD activity might be mediated by caspase activation. These data suggest that OD might represent a novel, efficient candidate agent for further experimentation in osteosarcoma treatment. PMID:26834484

  10. Apoptosis and autophagy induced by pyropheophorbide-α methyl ester-mediated photodynamic therapy in human osteosarcoma MG-63 cells.

    PubMed

    Huang, Qiu; Ou, Yun-Sheng; Tao, Yong; Yin, Hang; Tu, Ping-Hua

    2016-06-01

    Pyropheophorbide-α methyl ester (MPPa) was a second-generation photosensitizer with many potential applications. Here, we explored the impact of MPPa-mediated photodynamic therapy (MPPa-PDT) on the apoptosis and autophagy of human osteosarcoma (MG-63) cells as well as the relationships between apoptosis and autophagy of the cells, and investigated the related molecular mechanisms. We found that MPPa-PDT demonstrated the ability to inhibit MG-63 cell viability in an MPPa concentration- and light dose-dependent manner, and to induce apoptosis via the mitochondrial apoptosis pathway. Additionally, MPPa-PDT could also induce autophagy of MG-63 cell. Meanwhile, the ROS scavenger N-acetyl-L-cysteine (NAC) and the Jnk inhibitor SP600125 were found to inhibit the MPPa-PDT-induced autophagy, and NAC could also inhibit Jnk phosphorylation. Furthermore, pretreatment with the autophagy inhibitor 3-methyladenine or chloroquine showed the potential in reducing the apoptosis rate induced by MPPa-PDT in MG-63 cells. Our results indicated that the mitochondrial pathway was involved in MPPa-PDT-induced apoptosis of MG-63 cells. Meanwhile the ROS-Jnk signaling pathway was involved in MPPa-PDT-induced autophagy, which further promoted the apoptosis in MG-63 cells. PMID:27108344

  11. Responses of human MG-63 osteosarcoma cell line and human osteoblast-like cells to pulsed electromagnetic fields.

    PubMed

    Sollazzo, V; Traina, G C; DeMattei, M; Pellati, A; Pezzetti, F; Caruso, A

    1997-01-01

    We have studied the effects of low-energy, low-frequency pulsed electromagnetic fields (PEMF) on cell proliferation, in both human osteoblast-like cells obtained from bone specimens and in human MG-63 osteosarcoma cell line. Assessment of osteoblastic phenotype was performed both by immunolabeling with antiosteonectin antibody and by verifying the presence of parathyroid hormone receptors. The cells were placed in multiwell plates and set in a tissue culture incubator between a pair of Helmholtz coils powered by a pulse generator (1.3 ms, 75 Hz) for different periods of time. [3H]Thymidine incorporation was used to evaluate cell proliferation. Since it had previously been observed that the osteoblast proliferative response to PEMF exposure may also be conditioned by the presence of serum in the medium, experiments were carried out at different serum concentrations. [3H]Thymidine incorporation increases in osteoblast-like cells, when they are exposed to PEMF in the presence of 10% fetal calf serum (FCS). The greatest effect is observed after 24 hours of PEMF exposure. No effects on cell proliferation are observed when osteoblast-like cells are exposed to PEMF in the presence of 0.5% FCS or in a serum-free medium. On the other hand, PEMF-exposed MG-63 cells show increased cell proliferation either at 10% FCS, 0.5% FCS and in serum-free medium. Nevertheless, the maximum effect of PEMF exposure on MG-63 cell proliferation depends on the percentage of FCS in the medium. The higher the FCS concentration, the faster the proliferative response to PEMF exposure. Our results show that, although MG-63 cells display some similarity with human bone cells, their responses to PEMF's exposure are quite different from that observed in normal human bone cells. PMID:9383242

  12. Biological Characteristics of the MG-63 Human Osteosarcoma Cells on Composite Tantalum Carbide/Amorphous Carbon Films

    PubMed Central

    Chang, Yin-Yu; Huang, Heng-Li; Chen, Ya-Chi; Hsu, Jui-Ting; Shieh, Tzong-Ming; Tsai, Ming-Tzu

    2014-01-01

    Tantalum (Ta) is a promising metal for biomedical implants or implant coating for orthopedic and dental applications because of its excellent corrosion resistance, fracture toughness, and biocompatibility. This study synthesizes biocompatible tantalum carbide (TaC) and TaC/amorphous carbon (a-C) coatings with different carbon contents by using a twin-gun magnetron sputtering system to improve their biological properties and explore potential surgical implant or device applications. The carbon content in the deposited coatings was regulated by controlling the magnetron power ratio of the pure graphite and Ta cathodes. The deposited TaC and TaC/a-C coatings exhibited better cell viability of human osteosarcoma cell line MG-63 than the uncoated Ti and Ta-coated samples. Inverted optical and confocal imaging was used to demonstrate the cell adhesion, distribution, and proliferation of each sample at different time points during the whole culture period. The results show that the TaC/a-C coating, which contained two metastable phases (TaC and a-C), was more biocompatible with MG-63 cells compared to the pure Ta coating. This suggests that the TaC/a-C coatings exhibit a better biocompatible performance for MG-63 cells, and they may improve implant osseointegration in clinics. PMID:24760085

  13. Biological characteristics of the MG-63 human osteosarcoma cells on composite tantalum carbide/amorphous carbon films.

    PubMed

    Chang, Yin-Yu; Huang, Heng-Li; Chen, Ya-Chi; Hsu, Jui-Ting; Shieh, Tzong-Ming; Tsai, Ming-Tzu

    2014-01-01

    Tantalum (Ta) is a promising metal for biomedical implants or implant coating for orthopedic and dental applications because of its excellent corrosion resistance, fracture toughness, and biocompatibility. This study synthesizes biocompatible tantalum carbide (TaC) and TaC/amorphous carbon (a-C) coatings with different carbon contents by using a twin-gun magnetron sputtering system to improve their biological properties and explore potential surgical implant or device applications. The carbon content in the deposited coatings was regulated by controlling the magnetron power ratio of the pure graphite and Ta cathodes. The deposited TaC and TaC/a-C coatings exhibited better cell viability of human osteosarcoma cell line MG-63 than the uncoated Ti and Ta-coated samples. Inverted optical and confocal imaging was used to demonstrate the cell adhesion, distribution, and proliferation of each sample at different time points during the whole culture period. The results show that the TaC/a-C coating, which contained two metastable phases (TaC and a-C), was more biocompatible with MG-63 cells compared to the pure Ta coating. This suggests that the TaC/a-C coatings exhibit a better biocompatible performance for MG-63 cells, and they may improve implant osseointegration in clinics. PMID:24760085

  14. miR-205 suppresses the proliferative and migratory capacity of human osteosarcoma Mg-63 cells by targeting VEGFA

    PubMed Central

    Wang, Li; Shan, Minhong; Liu, Yang; Yang, Fengyi; Qi, Hongxia; Zhou, Lijuan; Qiu, Lirong; Li, Yanshuang

    2015-01-01

    Background Osteosarcoma (OS) is the most common primary bone malignancy in children and young adults. MiR-205 has been reported to be negatively correlated with the proliferation and metastasis of many types of cancer, while its effects on the malignant phenotype of OS are unclear. Methods Using TaqMan RT polymerase chain reaction analysis, we firstly explored the expression of miR-205 in a panel of OS cell lines. As the expression of miR-205 was significantly decreased in these cell lines, we sought to compensate for its loss by transfection of exogenous miR-205 mimic into MG-63 cells. To further understand the role of miR-205 in OS, we investigated the effects of miR-205 on the proliferation, migration, and invasion of MG-63 cells, and further explored the mechanisms that might be involved. Results We found that miR-205 was consistently suppressed in OS cells when compared with the normal human osteoblast (NHOst) cell line. Restored expression of miR-205 in the OS (MG-63) cell line significantly inhibited cell proliferation, migration, and invasion. Moreover, bioinformatic prediction suggested that vascular endothelial growth factor A (VEGFA) was the target oncogene for miR-205 in OS cells. Further quantitative RT polymerase chain reaction and Western blot assays identified that overexpression of miR-205 suppressed expression of VEGFA mRNA and protein. Restored expression of VEGFA in MG-63 cells previously treated with miR-205 mimic could partially abolish miR-205-mediated suppression of proliferation and invasion of these cells. Conclusion Collectively, these data suggest that miR-205 might function as a tumor suppressor in OS by, at least partially, targeting VEGFA. PMID:26396534

  15. Resveratrol inhibits canonical Wnt signaling in human MG-63 osteosarcoma cells.

    PubMed

    Zou, Yonggen; Yang, Jiexiang; Jiang, Dianming

    2015-11-01

    In the last 30 years, the 5-year-survival rate of patients with osteosarcoma has not improved as a result of the low prevalence and large tumor heterogeneity. Therefore, the development of novel drugs for the treatment of osteosarcoma is urgently required. The present study aimed to identify potential novel drugs for the treatment of osteosarcoma, thus used β‑catenin as a target and performed high content screening. In a total of 14 botanical extracts assessed, resveratrol markedly downregulated the expression of β‑catenin and significantly inhibited MG‑63 cell proliferation. CCK‑8 assay was used to confirm the anti‑osteosarcoma effect of resveratrol and flow cytometry and western blotting were performed to analyze the underlying mechanisms of the proapoptotic effects of resveratrol. β‑catenin is a vital member of the canonical Wnt signaling pathway and, therefore, the target genes of this pathway were further analyzed. The results of this analysis demonstrated that resveratrol suppressed the MG‑63 cells by inhibiting the canonical Wnt signaling pathway. PMID:26398440

  16. Adriamycin resistance-associated prohibitin gene inhibits proliferation of human osteosarcoma MG63 cells by interacting with oncogenes and tumor suppressor genes

    PubMed Central

    Du, Min-Dong; He, Kai-Yi; Qin, Gang; Chen, Jin; Li, Jin-Yi

    2016-01-01

    The resistance of cancer cells to chemotherapeutic agents is a major obstacle for successful chemotherapy, and the mechanism of chemoresistance remains unclear. The present study developed an adriamycin-resistant human osteosarcoma MG-63 sub-line (MG-63/ADR), and identified differentially expressed proteins that may be associated with adriamycin resistance. Two dimensional gel electrophoresis, matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis and a protein identification assay were performed. Western blot analysis was used to examine the prohibitin (PHB) levels in the MG-63/ADR cells. Quantitative polymerase chain reaction was utilized to detect adriamycin resistant-associated genes. Laser-scanning confocal microscope was employed to examine the colocalization of PHB with v-myc avian myelocytomatosis viral oncogene homolog (c-myc), FBJ murine osteosarcoma viral oncogene homolog (c-fos), tumor protein p53 and retinoblastoma 1 (Rb). In addition, the full length of the open reading frame of human PHB was subcloned into a lentiviral vector pLVX-puro. The proliferative rate of MG-63 cells was also investigated. The overall protein expression in MG-63/ADR cells was clearly suppressed. Three notable protein regions, representing high mobility group box 1, Ras homolog gene family, member A, and PHB, were identified to be significantly altered in MG-63/ADR cells when compared with its parental cells. Therefore, PHB modulated the chemoresistance of MG-63/ADR cells by interacting with multiple oncogenes or tumor suppressor genes (c-myc, c-fos, p53 and Rb). In addition, overexpression of PHB decreases the proliferative rate of MG-63 cells. In conclusion, PHB is an adriamycin resistance-associated gene, which may inhibit the proliferation of human osteosarcoma MG-63 cells by interacting with the oncogenes or tumor suppressor genes, c-myc, c-fos, p53 and Rb. PMID:27602127

  17. Aloe-emodin-mediated photodynamic therapy induces autophagy and apoptosis in human osteosarcoma cell line MG-63 through the ROS/JNK signaling pathway

    PubMed Central

    TU, PINGHUA; HUANG, QIU; OU, YUNSHENG; DU, XING; LI, KAITING; TAO, YONG; YIN, HANG

    2016-01-01

    The present study was carried out to investigate the effect and mechanisms of aloe-emodin (AE)-mediated photodynamic therapy (AE-PDT) on the human osteosarcoma cell line MG-63. After treatment with AE-PDT, the human osteosarcoma cell line MG-63 was tested for levels of viability, autophagy, reactive oxygen species (ROS) and apoptosis and changes in cell morphology with the Cell Counting Kit-8 (CCK-8), monodansylcadaverine (MDC) and Hoechst staining and transmission electron microscopy. The expression of proteins including LC-3, cleaved caspase-3, Beclin-1, Bcl-2, p-JNK, t-JNK and β-actin was examined with western blotting. AE-PDT significantly inhibited the viability of the MG-63 cells in an AE-concentration- and PDT energy density-dependent manner. Autophagy and apoptosis of MG-63 cells was substantially promoted in the AE-PDT group compared to the control group, the AE alone group and the light emitting diode (LED) alone group. Inhibition of autophagy by 3-meth-yladenine (3-MA) (5 mM) and chloroquine (CQ) (15 µM) significantly promoted the apoptosis rate and improved the sensitivity of the MG-63 cells to AE-PDT. AE-PDT was found to induce the expression of ROS and p-JNK. ROS scavenger, N-acetyl-L-cysteine (NAC, 5 mM), was able to hinder the autophagy, apoptosis and phosphorylation of JNK, and JNK inhibitor (SP600125, 10 µM) significantly inhibited the autophagy and apoptosis, and attenuated the sensitivity of MG63 cells to AE-PDT. In conclusion, AE-PDT induced the autophagy and apoptosis of human osteosarcoma cell line MG-63 through the activation of the ROS-JNK signaling pathway. Autophagy may play a protective role during the early stage following treatment of AE-PDT. PMID:27035222

  18. Ladder-Like Amplification of the Type I Interferon Gene Cluster in the Human Osteosarcoma Cell Line MG63

    PubMed Central

    Marella, Narasimha Rao V.; Zeitz, Michael J.; Malyavantham, Kishore S.; Pliss, Artem; Matsui, Sei-ichi; Goetze, Sandra; Bode, Juergen; Raska, Ivan; Berezney, Ronald

    2009-01-01

    Summary The organization of the type I interferon (IFN) gene cluster (9p21.3) was studied in a human osteosarcoma cell line (MG63). Array comparative genomic hybridization (aCGH) showed an amplification of ~six-fold which ended at both ends of the gene cluster with a deletion that extended throughout the 9p21.3 band. Spectral karyotyping (SKY) combined with fluorescence in situ hybridization (FISH) identified an arrangement of the gene cluster in a ladder-like array of 5–7 “bands” spanning a single chromosome termed the “IFN chromosome”. Chromosome painting revealed that the IFN chromosome is derived from components of chromosomes 4, 8 and 9. Labeling with centromeric probes demonstrated a ladder-like amplification of centromeric 4 and 9 sequences that colocalized with each other and a similar banding pattern of chromosome 4, as well as alternating with the IFN gene clusters. In contrast, centromere 8 was not detected on the IFN chromosome. One of the amplified centromeric 9 bands was identified as the functional centromere based on its location at the chromosome constriction and immunolocalization of the CENP-C protein. A model is presented for the generation of the IFN chromosome that involves breakage- fusion- bridge (BFB) events. PMID:19005637

  19. Apoptosis and antitumor effects induced by the combination of an mTOR inhibitor and an autophagy inhibitor in human osteosarcoma MG63 cells

    PubMed Central

    HORIE, RYOSUKE; NAKAMURA, OSAMU; YAMAGAMI, YOSHIKI; MORI, MASAKI; NISHIMURA, HIDEKI; FUKUOKA, NATSUKO; YAMAMOTO, TETSUJI

    2016-01-01

    The inhibition of the mammalian target of rapamycin (mTOR) signaling pathway promotes the initiation of autophagy. Although it remains under debate whether chemotherapy-induced autophagy in tumor cells is a protective response or is invoked to promote cell death, recent studies indicate that autophagy is a self-defense mechanism of cancer cells that are subjected to antitumor agents and that blocking autophagy can trigger apoptosis. The aim of this study was to examine the effects of rapamycin, an mTOR inhibitor, on MG63 osteosarcoma cells. We further examined whether the combination of rapamycin and the small molecule inhibitor of autophagy Spautin-1 (specific and potent autophagy inhibitor-1) enhanced the rapamycin-induced apoptosis in MG63 cells. We examined the effects of rapamycin treatment on cell proliferation, phosphorylation of mTOR pathway components, and autophagy by western blot analysis. Furthermore, we examined the effects of rapamycin with or without Spautin-1 on the induction of apoptosis by western blot analysis and immunohistochemical staining. We found that rapamycin inhibited cell proliferation and decreased the phosphorylation of mTOR pathway components in MG63 cells. Rapamycin induced the apoptosis of MG63 cells, and this apoptosis was enhanced by Spautin-1. It was considered that Spautin-1 suppressed the protective mechanism induced by rapamycin in tumor cells and induced apoptosis. Therefore, the combination of an mTOR inhibitor and an autophagy inhibitor may be effective in the treatment of osteosarcoma because it effectively induces the apoptotic pathway. PMID:26530936

  20. Selective inhibition of MG-63 osteosarcoma cell proliferation induced by curcumin-loaded self-assembled arginine-rich-RGD nanospheres

    PubMed Central

    Chang, Run; Sun, Linlin; Webster, Thomas J

    2015-01-01

    Osteosarcoma is the most frequent primary malignant form of bone cancer, comprising 30% of all bone cancer cases. The objective of this in vitro study was to develop a treatment against osteosarcoma with higher selectivity toward osteosarcoma cells and lower cytotoxicity toward normal healthy osteoblast cells. Curcumin (or diferuloylmethane) has been found to have antioxidant and anticancer effects by multiple cellular pathways. However, it has lower water solubility and a higher degradation rate in alkaline conditions. In this study, the amphiphilic peptide C18GR7RGDS was used as a curcumin carrier in aqueous solution. This peptide contains a hydrophobic aliphatic tail group leading to their self-assembly by hydrophobic interactions, as well as a hydrophilic head group composed of an arginine-rich and an arginine-glycine-aspartic acid structure. Through characterization by transmission electron microscopy, self-assembled structures of spherical amphiphilic nanoparticles (APNPs) with diameters of 10–20 nm in water and phosphate-buffered saline were observed, but this structure dissociated when the pH value was reduced to 4. Using a method of codissolution with acetic acid and dialysis tubing, the solubility of curcumin was enhanced and a homogeneous solution was formed in the presence of APNPs. Successful encapsulation of curcumin in APNPs was then confirmed by Fourier transform infrared and X-ray diffraction analyses. The cytotoxicity and cellular uptake of the APNP/curcumin complexes on both osteosarcoma and normal osteoblast cell lines were also evaluated by methyl-thiazolyl-tetrazolium assays and confocal fluorescence microscopy. The results showed that the curcumin-loaded APNPs had significant selective cytotoxicity against MG-63 osteosarcoma cells when compared with normal osteoblasts. We have demonstrated for the first time that APNPs can encapsulate hydrophobic curcumin in their hydrophobic cores, and curcumin-loaded APNPs could be an innovative treatment

  1. Study of the mechanism underlying the inhibitory effects of transglutaminase II on apoptosis in the osteosarcoma MG-63 cell line under hypoxic conditions

    PubMed Central

    WANG, GUOBIN; FU, LIMEI; CHEN, FANGMIN

    2015-01-01

    The aim of the present study was to investigate the association between the apoptosis phenomenon in the MG-63 osteosarcoma cell line, and transglutaminase II (TG2) expression. The relationship between the anti-apoptotic mechanism of TG2 and the expression of cytochrome c as well as caspase-3 under hypoxic conditions was also verified. A hypoxic culture of MG-63 cells was prepared. The hypoxia and TG2 siRNA hypoxia groups were established, and the cultures were incubated for 12 h under hypoxic conditions. TG2 activity, TG2 protein expression and its mRNA level were investigated. Cytochrome c and caspase-3 protein levels in the TG2 nucleus and cytoplasm were measured. The apoptotic rate was also monitored. The results showed that TG2 activity, TG2 protein expression and its mRNA level in the hypoxia group were significantly higher than those of the siRNA hypoxia group. The results showed statistically insignificant differences (P<0.05). By contrast, a comparison of the two groups in the cytoplasm yielded no statistically significant differences (P>0.05). Cytochrome c and caspase-3 protein levels in the hypoxia group were significantly higher than those of the TG2 siRNA hypoxia group. The results showed statistically significant differences (P<0.05). By contrast, the protein levels in the cytoplasm were significantly lower than those of the TG2 siRNA hypoxia group, with differences being statistically significant (P<0.05). The differences in apoptotic rates between the hypoxia and TG2 siRNA hypoxia groups were also statistically significant (P<0.05). Under hypoxic conditions, a high TG2 expression inhibited the apoptosis of the MG-63 osteosarcoma cell line. This effect was probably associated with its suppressive activity on the transportation of cytochrome c and caspase-3 from nucleus to cytoplasm. PMID:26788145

  2. Extracellular heat shock protein HSP90{beta} secreted by MG63 osteosarcoma cells inhibits activation of latent TGF-{beta}1

    SciTech Connect

    Suzuki, Shigeki; Kulkarni, Ashok B.

    2010-07-30

    Transforming growth factor-beta 1 (TGF-{beta}1) is secreted as a latent complex, which consists of latency-associated peptide (LAP) and the mature ligand. The release of the mature ligand from LAP usually occurs through conformational change of the latent complex and is therefore considered to be the first step in the activation of the TGF-{beta} signaling pathway. So far, factors such as heat, pH changes, and proteolytic cleavage are reportedly involved in this activation process, but the precise molecular mechanism is still far from clear. Identification and characterization of the cell surface proteins that bind to LAP are important to our understanding of the latent TGF-{beta} activation process. In this study, we have identified heat shock protein 90 {beta} (HSP90{beta}) from the cell surface of the MG63 osteosarcoma cell line as a LAP binding protein. We have also found that MG63 cells secrete HSP90{beta} into extracellular space which inhibits the activation of latent TGF-{beta}1, and that there is a subsequent decrease in cell proliferation. TGF-{beta}1-mediated stimulation of MG63 cells resulted in the increased cell surface expression of HSP90{beta}. Thus, extracellular HSP90{beta} is a negative regulator for the activation of latent TGF-{beta}1 modulating TGF-{beta} signaling in the extracellular domain. -- Research highlights: {yields} Transforming growth factor-beta 1 (TGF-{beta}1) is secreted as a latent complex. {yields} This complex consists of latency-associated peptide (LAP) and the mature ligand. {yields} The release of the mature ligand from LAP is the first step in TGF-{beta} activation. {yields} We identified for the first time a novel mechanism for this activation process. {yields} Heat shock protein 90 {beta} is discovered as a negative regulator for this process.

  3. Activation of the MAPK/Akt/Nrf2-Egr1/HO-1-GCLc axis protects MG-63 osteosarcoma cells against 15d-PGJ2-mediated cell death

    PubMed Central

    Koyani, Chintan N.; Kitz, Kerstin; Rossmann, Christine; Bernhart, Eva; Huber, Evelyn; Trummer, Christopher; Windischhofer, Werner; Sattler, Wolfgang; Malle, Ernst

    2016-01-01

    Despite considerable efforts to improve treatment modalities for osteosarcoma (OS), patient survival remains poor mainly due to pro-survival pathways in OS cells. Among others, prostaglandins (PGs) are the potent regulators of bone homoeostasis and OS pathophysiology. Therefore, the present study aimed to elucidate the impact of 15-deoxy-Δ12,14-PGJ2 (15d-PGJ2, a stable PGD2 degradation product) on cell death/cell survival pathways in p53-deficient MG-63 OS cells. Our findings show that 15d-PGJ2 induces generation of reactive oxygen species that promote p38 MAPK activation and subsequent Akt phosphorylation. This pathway induced nuclear expression of Nrf2 and Egr1, and increased transcription of haem oxygenase-1 (HO-1) and the catalytic subunit of glutamate cysteine ligase (GCLc), catalysing the first step in GSH synthesis. Silencing of Nrf2, Egr1 and HO-1 significantly elevated 15d-PGJ2-mediated reduction of cellular metabolic activity. Activation of cell survival genes including HO-1 and GCLc inhibited 15d-PGJ2-induced cleavage of pro-caspase-3 and PARP. Annexin V/propidium iodide staining showed an increase in early/late apoptotic cells in response to 15d-PGJ2. The observed 15d-PGJ2-mediated signalling events are independent of PGD2 receptors (DP1 and DP2) and PPARγ. In addition, the electrophilic carbon atom C9 is a prerequisite for the observed activity of 15d-PGJ2. The present data show that the intracellular redox imbalance acted as a node and triggered both death and survival pathways in response to 15d-PGJ2. Pharmacological or genetic interference of the pro-survival pathway, the p38 MAPK/Akt/Nrf2-Egr1/HO-1-GCLc axis, sensitizes MG-63 cells towards 15d-PGJ2-mediated apoptosis. PMID:26801686

  4. Activation of the MAPK/Akt/Nrf2-Egr1/HO-1-GCLc axis protects MG-63 osteosarcoma cells against 15d-PGJ2-mediated cell death.

    PubMed

    Koyani, Chintan N; Kitz, Kerstin; Rossmann, Christine; Bernhart, Eva; Huber, Evelyn; Trummer, Christopher; Windischhofer, Werner; Sattler, Wolfgang; Malle, Ernst

    2016-03-15

    Despite considerable efforts to improve treatment modalities for osteosarcoma (OS), patient survival remains poor mainly due to pro-survival pathways in OS cells. Among others, prostaglandins (PGs) are the potent regulators of bone homoeostasis and OS pathophysiology. Therefore, the present study aimed to elucidate the impact of 15-deoxy-Δ(12,14)-PGJ2 (15d-PGJ2, a stable PGD2 degradation product) on cell death/cell survival pathways in p53-deficient MG-63 OS cells. Our findings show that 15d-PGJ2 induces generation of reactive oxygen species that promote p38 MAPK activation and subsequent Akt phosphorylation. This pathway induced nuclear expression of Nrf2 and Egr1, and increased transcription of haem oxygenase-1 (HO-1) and the catalytic subunit of glutamate cysteine ligase (GCLc), catalysing the first step in GSH synthesis. Silencing of Nrf2, Egr1 and HO-1 significantly elevated 15d-PGJ2-mediated reduction of cellular metabolic activity. Activation of cell survival genes including HO-1 and GCLc inhibited 15d-PGJ2-induced cleavage of pro-caspase-3 and PARP. Annexin V/propidium iodide staining showed an increase in early/late apoptotic cells in response to 15d-PGJ2. The observed 15d-PGJ2-mediated signalling events are independent of PGD2 receptors (DP1 and DP2) and PPARγ. In addition, the electrophilic carbon atom C9 is a prerequisite for the observed activity of 15d-PGJ2. The present data show that the intracellular redox imbalance acted as a node and triggered both death and survival pathways in response to 15d-PGJ2. Pharmacological or genetic interference of the pro-survival pathway, the p38 MAPK/Akt/Nrf2-Egr1/HO-1-GCLc axis, sensitizes MG-63 cells towards 15d-PGJ2-mediated apoptosis. PMID:26801686

  5. DNA demethylation in the PTEN gene promoter induced by 5-azacytidine activates PTEN expression in the MG-63 human osteosarcoma cell line.

    PubMed

    Song, Deye; Ni, Jiangdong; Xie, Hongming; Ding, Muliang; Wang, Jun

    2014-05-01

    This study used the MG-63 osteosarcoma cell line to investigate the demethylation of the phosphate and tension homolog (PTEN) gene promoter and the change in PTEN gene expression levels, which are caused by the methylation inhibitor 5-azacytidine (5-Zac), and the association between the two. Different concentrations of 5-Zac (0, 5 and 10 μmol/l) were added into the MG-63 cell culture medium and the cells were cultured for 72 h. The following techniques were performed on the cells: Western blot analysis to detect the PTEN protein; reverse transcription-polymerase chain reaction (PCR) to detect the mRNA transcription levels of the PTEN gene; flow cytometry to detect the cell apoptotic rate; and sodium bisulfate to deal with the DNA of each group. The genes of the PTEN promoter and the transcription factors specificity protein 1 (Sp1) and Myc were PCR amplified and transformed into Escherichia coli, then a number of clones were selected for sequencing and the methylation status of the amplified PTEN promoter fragment was detected. Following culture of the MG-63 cells with 5-Zac at concentrations of 0, 5 and 10 μmol/l for 72 h, the expression levels of PTEN protein in each group were gradually increased, presenting a concentration-dependent effect: Group 0 μmol/l compared with groups 5 and 10 μmol/l, P<0.05; and group 5 μmol/l compared with group 10 μmol/l, P=0.007. The mRNA expression levels of the PTEN gene significantly increased. The apoptotic rates of groups 0, 5 and 10 μmol/l were 0.69±0.42, 2.50±0.30 and 6.59±0.62%, and significant differences (P<0.01) were observed between every two groups. The bisulfate DNA sequencing results of three groups showed that, following the treatment with 5-Zac, the binding of the CG site to transcription factors was affected by demethylation. The average rate of demethylation indicated a statistical difference among the three groups. In conclusion, the methylation inhibitor 5-Zac leads to a significant increase in the

  6. DNA demethylation in the PTEN gene promoter induced by 5-azacytidine activates PTEN expression in the MG-63 human osteosarcoma cell line

    PubMed Central

    SONG, DEYE; NI, JIANGDONG; XIE, HONGMING; DING, MULIANG; WANG, JUN

    2014-01-01

    This study used the MG-63 osteosarcoma cell line to investigate the demethylation of the phosphate and tension homolog (PTEN) gene promoter and the change in PTEN gene expression levels, which are caused by the methylation inhibitor 5-azacytidine (5-Zac), and the association between the two. Different concentrations of 5-Zac (0, 5 and 10 μmol/l) were added into the MG-63 cell culture medium and the cells were cultured for 72 h. The following techniques were performed on the cells: Western blot analysis to detect the PTEN protein; reverse transcription-polymerase chain reaction (PCR) to detect the mRNA transcription levels of the PTEN gene; flow cytometry to detect the cell apoptotic rate; and sodium bisulfate to deal with the DNA of each group. The genes of the PTEN promoter and the transcription factors specificity protein 1 (Sp1) and Myc were PCR amplified and transformed into Escherichia coli, then a number of clones were selected for sequencing and the methylation status of the amplified PTEN promoter fragment was detected. Following culture of the MG-63 cells with 5-Zac at concentrations of 0, 5 and 10 μmol/l for 72 h, the expression levels of PTEN protein in each group were gradually increased, presenting a concentration-dependent effect: Group 0 μmol/l compared with groups 5 and 10 μmol/l, P<0.05; and group 5 μmol/l compared with group 10 μmol/l, P=0.007. The mRNA expression levels of the PTEN gene significantly increased. The apoptotic rates of groups 0, 5 and 10 μmol/l were 0.69±0.42, 2.50±0.30 and 6.59±0.62%, and significant differences (P<0.01) were observed between every two groups. The bisulfate DNA sequencing results of three groups showed that, following the treatment with 5-Zac, the binding of the CG site to transcription factors was affected by demethylation. The average rate of demethylation indicated a statistical difference among the three groups. In conclusion, the methylation inhibitor 5-Zac leads to a significant increase in the

  7. A new oxidovanadium(IV) complex of oxodiacetic acid and dppz: spectroscopic and DFT study. Antitumor action on MG-63 human osteosarcoma cell line.

    PubMed

    León, Ignacio E; Parajón-Costa, Beatriz S; Franca, Carlos A; Etcheverry, Susana B; Baran, Enrique J

    2015-04-01

    The oxidovanadium(IV) complex of oxodiacetic acid (H2ODA) and dppz (dipyrido[3,2-a:2',3'-c] phenazine) of stoichiometry [VO(ODA)(dppz)]·3H2O could be synthesized for the first time by reaction between [VO(ODA)(H2O)2] and dppz. It was characterized by infrared and electronic spectroscopies. Its optimized molecular structure was obtained by DFT calculations, as it was impossible to grow single crystals adequate for crystallographic studies. The antitumor action of the complex on MG-63 human osteosarcoma cell line was also investigated. It was found that it caused a concentration-related inhibitory effect in the concentration range between 5 and 25 μM and diminished the cell viability ca. 45% in the range from 25 to 100 μM, without dose/response effects in this range. These biological effects are, in general, similar to those previously reported for the related [VO(ODA)(ophen)]·1.5H2O complex. PMID:25534289

  8. Effects of RNA interference-mediated knockdown of livin and survivin using monomethoxypolyethylene glycol-chitosan nanoparticles in MG-63 osteosarcoma cells.

    PubMed

    Guan, Hua-Peng; Sun, Jian-Zhong; Feng, Xiao-Lei; Chen, Jin-Shui; Chen, Fang-Jing; Cheng, Xiao-Fei; Liu, Xin-Wei; Ni, Bin

    2016-02-01

    MG-63 human osteosarcoma cells were transfected with short hairpin RNA (shRNA) against livin and survivin using monomethoxypolyethylene glycol‑chitosan (mPEG‑CS) nanoparticles (NPs) as carriers, with the aim of evaluating the effect on cell proliferation and apoptosis. mPEG‑CS NPs sized ~100 nm were prepared by ionic crosslinking. mPEG‑CS‑livin shRNA, mPEG‑CS‑survivin shRNA and mPEG‑CS‑(livin shRNA + survivin shRNA) NPs were constructed by electrostatic adsorption at NP suspension/gene solution ratios of 3:1 to transfect MG‑63 cells. The expression levels of livin and survivin mRNA and protein were measured by reverse transcription‑polymerase chain reaction and western blotting, respectively. The inhibitory effects of downregulated livin and survivin expression on cell proliferation were measured using an MTT assay. The apoptosis‑inducing effects of livin and surivin knockdown were investigated using a Hoechst staining kit. All shRNA groups resulted in reduced expression of livin and survivin mRNA and protein in MG‑63 cells. The MTT assay and Hoechst staining indicated that simultaneous knockdown of livin and survivin genes inhibited the proliferation of MG‑63 cells and promoted their apoptosis, to a greater extent than knocking down either gene individually. The simultaneous interference mediated by mPEG‑CS NPs significantly reduced livin and survivin expression in MG‑63 cells, suppressed proliferation and facilitated apoptosis, to a greater extent than knockdown of either livin or survivin alone were. Thus the results indicate a synergistic effect of livin and survivin. PMID:26708654

  9. Antitumor activity of neurokinin-1 receptor antagonists in MG-63 human osteosarcoma xenografts.

    PubMed

    Muñoz, Miguel; Berger, Michael; Rosso, Marisa; Gonzalez-Ortega, Ana; Carranza, Andrés; Coveñas, Rafael

    2014-01-01

    Osteosarcoma is a highly malignant bone tumor in children and adolescents. Aprepitant is a selective high‑affinity antagonist of the human neurokinin‑1 (NK‑1) receptor (NK1R) with robust antitumor activity. No data exist on the presence of NK1R in osteosarcoma and whether this tumor responds to NK1R antagonists. Here, we analyzed the expression of NK1R in the human osteosarcoma cell line MG-63 with western blot analysis and PCR and found significant expression both at the protein and mRNA levels. We further studied the growth inhibitory capacity of aprepitant and other NK1R antagonists on MG-63 in vitro using an MTS cytotoxicity assay and DAPI staining. All antagonists induced tumor growth inhibition and apoptosis. Synergism was observed for the combination of L-733,060 with common cytostatic drugs in MG-63, but not in non-malignant HEK293 cells. Pretreatment of HEK293 with L-733,060 prior to exposure to cytostatic drugs partially protected HEK293 cells from inhibition by these drugs. Furthermore, nanomolar concentrations of substance P (SP), the natural ligand of the NK1R, increased the growth rate of MG‑63 cells and micromolar concentrations of aprepitant inhibited SP-induced growth in a dose‑dependent manner. In vivo, a xenograft for MG-63 was created in nude mice and treated with peritumoral s.c. injections of fosaprepitant, which resulted in a significant reduction of tumor volume. Collectively, we demonstrated for the first time that the NK1R is expressed in human osteosarcoma cell line MG‑63 and that this receptor can be targeted with NK1R antagonists both in vitro as well as in vivo. PMID:24190675

  10. Effect of radiation on cytotoxicity, apoptosis and cell cycle arrest of human osteosarcoma MG-63 induced by a ruthenium(II) complex

    NASA Astrophysics Data System (ADS)

    Liu, Si-Hong; Zhao, Jian-Hua; Deng, Kun-Kang; Wu, Yong; Zhu, Jian-Wei; Liu, Qing-Hua; Xu, Hui-Hua; Wu, Hai-Feng; Li, Xin-Yan; Wang, Jian-Wei; Guo, Qi-Feng

    2015-04-01

    Radiation has large influence on the cytotoxicity, apoptosis and cell cycle arrest. The bioactivity of ruthenium(II) complex [Ru(dmb)2(DBHIP)](ClO4)2 (Ru1) (DBHIP = 2-(3,5-dibromo-4-hydroxylphenyl)imidazo[4,5-f][1,10]phenanthroline) was investigated in the absence and presence of radiation. The cytotoxicity of Ru1 against MG-63 cells was evaluated by CCK-8 method. Ru1 shows high cytotoxicity upon radiation. Radiation can enhance the cytotoxicity of Ru1 on MG-63 cells. The apoptosis was studied by Hoechst 33258 staining method and flow cytometry. The reactive oxygen species, mitochondrial membrane potential, cell cycle arrest and western blot analysis were investigated in detail. The complex induces the apoptosis in MG-63 cells through ROS-mediated mitochondrial dysfunction pathway.

  11. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    SciTech Connect

    Fang, Dengfeng; Yang, Hui; Lin, Jing; Teng, Yi; Jiang, Yingying; Chen, Jiao; Li, Yu

    2015-02-20

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis.

  12. GSK3β negatively regulates HIF1α mRNA stability via nucleolin in the MG63 osteosarcoma cell line.

    PubMed

    Cheng, Dong-dong; Zhao, Hai-guang; Yang, Yun-song; Hu, Tu; Yang, Qing-cheng

    2014-01-10

    Hypoxia-inducible factor 1α (HIF1α) is a transcription factor involved in the growth, invasion and metastasis of malignant tumors. Glycogen synthase kinase 3 beta (GSK3β) is a protein kinase involved in a variety of signaling pathways, such as the Wnt and NF-κB pathways; this kinase can affect tumor progress through the regulation of transcription factor expression and apoptosis. Recent studies showed that GSK3β was involved in the expression of HIF1α. However, the effect of GSK3β on HIF1α expression in osteosarcoma cells remains unknown. To understand the relationship between GSK3β and HIF1α comprehensively, small RNA interference techniques, Western blot analyses, quantitative real-time PCR analyses and luciferase assays were used in our study. Experimental data revealed that inhibition of GSK3β could increase HIF1α protein levels and expression of its target genes by increasing the stability of the HIF1α mRNA, not by affecting the HIF1α protein stability, and that this process could be mediated by nucleolin. PMID:24333432

  13. Cloning the Gravity and Shear Stress Related Genes from MG-63 Cells by Subtracting Hybridization

    NASA Astrophysics Data System (ADS)

    Zhang, Shu; Dai, Zhong-quan; Wang, Bing; Cao, Xin-sheng; Li, Ying-hui; Sun, Xi-qing

    2008-06-01

    Background The purpose of the present study was to clone the gravity and shear stress related genes from osteoblast-like human osteosarcoma MG-63 cells by subtractive hybridization. Method MG-63 cells were divided into two groups (1G group and simulated microgravity group). After cultured for 60 h in two different gravitational environments, two groups of MG-63 cells were treated with 1.5Pa fluid shear stress (FSS) for 60 min, respectively. The total RNA in cells was isolated. The gravity and shear stress related genes were cloned by subtractive hybridization. Result 200 clones were gained. 30 positive clones were selected using PCR method based on the primers of vector and sequenced. The obtained sequences were analyzed by blast. changes of 17 sequences were confirmed by RT-PCR and these genes are related to cell proliferation, cell differentiation, protein synthesis, signal transduction and apoptosis. 5 unknown genes related to gravity and shear stress were found. Conclusion In this part of our study, our result indicates that simulated microgravity may change the activities of MG-63 cells by inducing the functional alterations of specific genes.

  14. Discovery of 2-((3-cyanopyridin-2-yl)thio)acetamides as human lactate dehydrogenase A inhibitors to reduce the growth of MG-63 osteosarcoma cells: Virtual screening and biological validation.

    PubMed

    Cui, Wei; Lv, Wei; Qu, Ying; Ma, Rui; Wang, Yi-Wei; Xu, Yong-Jun; Wu, Di; Chen, Xuanhuang

    2016-08-15

    Lactate dehydrogenase A (LDHA) has emerged as an attractive target in the oncology field. In this paper, we present the identification of 2-((3-cyanopyridin-2-yl)thio)acetamide-containing compounds as LDHA inhibitors. The in vitro enzymatic assay suggested that inhibitor 9 had good inhibitory potency against LDHA with IC50 value as 1.24μM. Cytotoxicity assay showed that inhibitor 9 strongly inhibited the proliferation of cancer cell MG-63 (EC50=0.98μM). These findings indicated that inhibitor 9 could be employed as a lead for developing more potent LDHA inhibitor with anti-proliferative potency. PMID:27406795

  15. Videography supported adhesion, and proliferation behavior of MG-63 osteoblastic cells on 2.5D titania nanotube matrices.

    PubMed

    Manurung, Robeth Viktoria; Fu, Pei-Wen; Chu, Yeh-Shiu; Lo, Chun-Min; Chattopadhyay, Surojit

    2016-04-01

    Human osteosarcoma cells MG-63 were cultured on anodically etched titania nanotubes (TiO2 NT), with diameters ranging from 40-100 nm, to study the correlations between cell proliferation and adhesion on the 2.5 dimensional (2.5D) extracellular matrix (ECM). Unlike other reports, mostly based on mouse stem cells, and 2D cell culture, our studies indicate that the 2.5D NT promote higher proliferation and activity, but less 2D adhesion. Proliferation of the MG-63 cells was significantly higher in the NTs, the best being the 70 nm diameter sample, compared to planar titania (control). This is consistent with previous studies. However, cellular adhesion was stronger on TiO2 NT with increasing diameter, and highest on the control as obtained from shear stress measurement, paxilin imaging, and western blot measurements probing focal adhesion kinase, p130 CAS, and extracellular-regulated kinase, in addition to cell morphology imaging by fluorescence microscopy. We provide direct videography of cell migration, and cell speed data indicating faster filopodial activity on the TiO2 NT surfaces having lower adhesion. This evidence was not available previously. The NT matrices promote cells with smaller surface area, because of less 2D stretching. In contrast, on comparatively planar 2D-like surfaces uniaxial stretching of the cell body with strong anchoring of the filopodia, resulted in larger cell surface area, and demonstrated stronger adhesion. The difference in the results, with those previously published, may be generally attributed to, among others, the use of mouse stem cells (human osteosarcoma used here), and unannealed as-grown TiO2 NTs used previously (annealed ECMs used here). © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 842-852, 2016. PMID:26650774

  16. Expression of extracellular calcium-sensing receptor in human osteoblastic MG-63 cell line

    NASA Technical Reports Server (NTRS)

    Yamaguchi, T.; Chattopadhyay, N.; Kifor, O.; Ye, C.; Vassilev, P. M.; Sanders, J. L.; Brown, E. M.

    2001-01-01

    We have previously shown the expression of the extracellular calcium (Ca2+o)-sensing receptor (CaR) in osteoblast-like cell lines, and others have documented its expression in sections of murine, bovine, and rat bone. The existence of the CaR in osteoblasts remains controversial, however, since some studies have failed to document its expression in the same osteoblast-like cell lines. The goals of the present study were twofold. 1) We sought to determine whether the CaR is expressed in the human osteoblast-like cell line, MG-63, which has recently been reported by others not to express this receptor. 2) We investigated whether the CaR, if present in MG-63 cells, is functionally active, since most previous studies have not proven the role of the CaR in mediating known actions of Ca2+o on osteoblast-like cells. We used immunocytochemistry and Western blotting with the specific, affinity-purified anti-CaR antiserum 4637 as well as Northern blot analysis and RT-PCR using a riboprobe and PCR primers specific for the human CaR, respectively, to show readily detectable CaR protein and mRNA expression in MG-63 cells. Finally, we employed the patch-clamp technique to show that an elevation in Ca2+o as well as the specific, allosteric CaR activator NPS R-467 (0.5 microM), but not its less active stereoisomer NPS S-467 (0.5 microM), activate an outward K+ channel in MG-63 cells, strongly suggesting that the CaR in MG-63 cells is not only expressed but is functionally active.

  17. Capsaicin induces immunogenic cell death in human osteosarcoma cells

    PubMed Central

    Jin, Tao; Wu, Hongyan; Wang, Yanlin; Peng, Hao

    2016-01-01

    Immunogenic cell death (ICD) is characterized by the early surface exposure of calreticulin (CRT). As a specific signaling molecule, CRT on the surface of apoptotic tumor cells mediates the recognition and phagocytosis of tumor cells by antigen presenting cells. To date, only a small quantity of anti-cancer chemicals have been found to induce ICD, therefore it is clinically important to identify novel chemicals that may induce ICD. The purpose of the present study is to explore the function of capsaicin in inducing ICD. In the current study, MTT assays were used to examine the growth inhibiting effects of MG-63 cells when they were treated with capsaicin or cisplatin. Mitochondrial membrane potential and western blot analysis were used to investigate capsaicin- and cisplatin-induced apoptosis. In addition, the effects of capsaicin and cisplatin were evaluated for their abilities in inducing calreticulin membrane translocation and mediating ICD in human osteosarcoma cells (MG-63). The results demonstrated that capsaicin and cisplatin can induce the apoptosis of MG-63 cells. However, only capsaicin induced a rapid translocation of CRT from the intracellular space to the cell surface. Treatment with capsaicin increased phagocytosis of MG-63 cells by dendritic cells (DCs), and these MG-63-loaded DCs could efficiently stimulate the secretion of IFN-γ by lymphocytes. These results identify capsaicin as an anti-cancer agent capable of inducing ICD in human osteosarcoma cells in vitro. PMID:27446273

  18. Plasma deposited composite coatings to control biological response of osteoblast-like MG-63 cells

    NASA Astrophysics Data System (ADS)

    Keremidarska, M.; Radeva, E.; Eleršič, K.; Iglič, A.; Pramatarova, L.; Krasteva, N.

    2014-12-01

    The successful osseointegration of a bone implant is greatly dependent on its ability to support cellular adhesion and functions. Deposition of thin composite coatings onto the implant surface is a promising approach to improve interactions with cells without compromising implant bulk properties. In this work, we have developed composite coatings, based on hexamethyldisiloxane (HMDS) and detonation nanodiamond (DND) particles and have studied adhesion, growth and function of osteoblast-like MG-63 cells. PPHMDS/DND composites are of interest for orthopedics because they combine superior mechanical properties and good biocompatibility of DND with high adherence of HMDS to different substrata including glass, metals and plastics. We have used two approaches of the implementation of DND particles into a polymer matrix: pre-mixture of both components followed by plasma polymerization and layer-by-layer deposition of HMDS and DND particles and found that the deposition approach affects significantly the surface properties of the resulting layers and cell behaviour. The composite, prepared by subsequent deposition of monomer and DND particles was hydrophilic, with a rougher surface and MG-63 cells demonstrated better spreading, growth and function compared to the other composite which was hydrophobic with a smooth surface similarly to unmodified polymer. Thus, by varying the deposition approach, different PPHMDS/DND composite coatings, enhancing or inhibiting osteoblast adhesion and functions, can be obtained. In addition, the effect of fibronectin pre-adsorption was studied and was found to increase greatly MG-63 cell spreading.

  19. Antitumor activity of dobutamine on human osteosarcoma cells

    PubMed Central

    YIN, JUN; DONG, QIRONG; ZHENG, MINQIAN; XU, XIAOZU; ZOU, GUOYOU; MA, GUOLIN; LI, KEFENG

    2016-01-01

    Dobutamine has been widely used for the treatment of heart failure and cardiogenic shock since the 1970s. Osteosarcoma is the most commonly observed malignant bone tumor in children. Currently, there are no effective drugs for the treatment of osteosarcoma. In the present study, the potential anticancer activity of dobutamine on human osteosarcoma cells was examined. Human osteosarcoma MG-63 cells were treated with dobutamine at various concentrations and for various incubation times. The inhibition of cell growth by dobutamine was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Flow cytometry was utilized to evaluate the effect of dobutamine on cell apoptosis and the cell cycle. Furthermore, the expression levels of caspase-3 and caspase-9 were assessed by western blot analysis. The influence of dobutamine on cancer cell migration and invasion was additionally evaluated using wound-healing assay and the Boyden Chamber migration method. Dobutamine significantly inhibited the growth of MG-63 cells at a concentration of 10 µM or higher when incubated for 12 h or longer (P=0.023). Dobutamine augmented cell apoptosis and arrested the cell cycle in the G2/M phase. Western blot analysis revealed that dobutamine induces expression of caspase-3 and caspase-9. In addition, the invasiveness and migration of MG-63 cells was inhibited by dobutamine in a concentration-dependent manner. The results of the present study may lead to novel applications for dobutamine in the treatment of osteosarcoma. PMID:27284371

  20. MicroRNA-224 promotes the sensitivity of osteosarcoma cells to cisplatin by targeting Rac1.

    PubMed

    Geng, Shuo; Gu, Lina; Ju, Fang; Zhang, Hepeng; Wang, Yiwen; Tang, Han; Bi, ZhengGang; Yang, Chenglin

    2016-09-01

    Osteosarcoma is the most common primary bone tumour in children and adolescents. Accumulating evidence has shown that microRNAs (miRNAs) participate in the development of almost all types of cancer. Here, we investigated the role of miR-224 in the development and progression of osteosarcoma. We demonstrated that miR-224 was down-regulated in osteosarcoma cell lines and tissues. Lower miR-224 levels were correlated with shorter survivalin osteosarcoma patients. Furthermore, overexpression of miR-224 suppressed osteosarcoma cell proliferation, migration and invasion and contributed to the increased sensitivity of MG-63 cells to cisplatin. We identified Rac1 as a direct target gene of miR-224 in osteosarcoma. Rac1 expression was up-regulated in the osteosarcoma cell lines and tissues, and there was an inverse correlation between Rac1 and miR-224 expression in osteosarcoma tissues. Furthermore, rescuing Rac1 expression decreased the sensitivity of miR-224-overexpressing MG-63 cells to cisplatin. We also demonstrated that ectopic expression of Rac1 promoted the proliferation, migration and invasion of miR-224-overexpressing MG-63 cells. These data suggest that miR-224 plays a tumour suppressor role in the development of osteosarcoma and is related to the sensitivity of osteosarcoma to cisplatin. PMID:27222381

  1. Antisense inhibition of hyaluronan synthase-2 in human osteosarcoma cells inhibits hyaluronan retention and tumorigenicity

    SciTech Connect

    Nishida, Yoshihiro . E-mail: ynishida@med.nagoya-u.ac.jp; Knudson, Warren; Knudson, Cheryl B.; Ishiguro, Naoki

    2005-07-01

    Osteosarcoma is a common malignant bone tumor associated with childhood and adolescence. The results of numerous studies have suggested that hyaluronan plays an important role in regulating the aggressive behavior of various types of cancer cells. However, no studies have addressed hyaluronan with respect to osteosarcomas. In this investigation, the mRNA expression copy number of three mammalian hyaluronan synthases (HAS) was determined using competitive RT-PCR in the osteoblastic osteosarcoma cell line, MG-63. MG-63 are highly malignant osteosarcoma cells with an abundant hyaluronan-rich matrix. The results demonstrated that HAS-2 is the predominant HAS in MG-63. Accumulation of intracellular hyaluronan increased in association with the proliferative phase of these cells. The selective inhibition of HAS-2 mRNA in MG-63 cells by antisense phosphorothioate oligonucleotides resulted in reduced hyaluronan accumulation by these cells. As expected, the reduction in hyaluronan disrupted the assembly of cell-associated matrices. However, of most interest, coincident with the reduction in hyaluronan, there was a substantial decrease in cell proliferation, a decrease in cell motility and a decrease in cell invasiveness. These data suggest that hyaluronan synthesized by HAS-2 in MG-63 plays a crucial role in osteosarcoma cell proliferation, motility, and invasion.

  2. SRCIN1 Suppressed Osteosarcoma Cell Proliferation and Invasion.

    PubMed

    Wang, Peng; Wang, Hu; Li, Xiaotao; Liu, Ying; Zhao, Chengbin; Zhu, Daling

    2016-01-01

    SRCIN1 (SRC kinase signalling inhibitor 1) is a new tumor suppressor gene. Previous studies showed that SRCIN1 played a tumor suppressor role in the development of lung cancer and breast cancer. However, the role of SRCIN1 in osteosarcoma is still unknown. In this study, we demonstrated that SRCIN1 was downregulated in osteosarcoma cell lines compared with osteoblastic cell line. Moreover, SRCIN1 was downregulated in osteosarcoma tissues compared with the adjacent tissues. Further investigation revealed that overexpression of SRCIN1 inhibited the osteosarcoma cell line MG-63 proliferation. This effect was confirmed by measuring the ki-67 and PCNA expression. SRCIN1 overexpression promoted E-cadherin expression and suppressed N-cadherin, Vimentin and Snail expression, suggesting that SRCIN1 overexpression inhibited EMT of the osteosarcoma cell. In addition, ectopic expression of SRCIN1 inhibited the MG-63 cell colony formation and invasion. These data suggested that SRCIN1 acted as a tumor suppressor gene in the development of osteosarcoma. PMID:27513473

  3. SRCIN1 Suppressed Osteosarcoma Cell Proliferation and Invasion

    PubMed Central

    Wang, Peng; Wang, Hu; Li, Xiaotao; Liu, Ying; Zhao, Chengbin; Zhu, Daling

    2016-01-01

    SRCIN1 (SRC kinase signalling inhibitor 1) is a new tumor suppressor gene. Previous studies showed that SRCIN1 played a tumor suppressor role in the development of lung cancer and breast cancer. However, the role of SRCIN1 in osteosarcoma is still unknown. In this study, we demonstrated that SRCIN1 was downregulated in osteosarcoma cell lines compared with osteoblastic cell line. Moreover, SRCIN1 was downregulated in osteosarcoma tissues compared with the adjacent tissues. Further investigation revealed that overexpression of SRCIN1 inhibited the osteosarcoma cell line MG-63 proliferation. This effect was confirmed by measuring the ki-67 and PCNA expression. SRCIN1 overexpression promoted E-cadherin expression and suppressed N-cadherin, Vimentin and Snail expression, suggesting that SRCIN1 overexpression inhibited EMT of the osteosarcoma cell. In addition, ectopic expression of SRCIN1 inhibited the MG-63 cell colony formation and invasion. These data suggested that SRCIN1 acted as a tumor suppressor gene in the development of osteosarcoma. PMID:27513473

  4. Nanocrystalline diamond: In vitro biocompatibility assessment by MG63 and human bone marrow cells cultures.

    PubMed

    Amaral, M; Dias, A G; Gomes, P S; Lopes, M A; Silva, R F; Santos, J D; Fernandes, M H

    2008-10-01

    Nanocrystalline diamond (NCD) has a great potential for prosthetic implants coating. Nevertheless, its biocompatibility still has to be better understood. To do so, we employed several materials characterization techniques (SEM, AFM, micro-Raman spectroscopy) and cell culture assays using MG63 osteoblast-like and human bone marrow cells. Biochemical routines (MTT assays, Lowry's method, ALP activity) supported by SEM and confocal microscopy characterization were carried out. We used silicon nitride (Si3N4) substrates for NCD coatings based on a previous demonstration of the superior adhesion and tribological performance of these NCD coated ceramics. Results demonstrate an improved human osteoblast proliferation and the stimulation of differentiated markers, like ALP activity and matrix mineralization, compared with standard polystyrene tissue culture plates. The nanometric featuring of NCD, associated to its chemical affinity are key points for bone regeneration purposes. PMID:18085649

  5. Effects of fluoridation of porcine hydroxyapatite on osteoblastic activity of human MG63 cells

    NASA Astrophysics Data System (ADS)

    Li, Zhipeng; Huang, Baoxin; Mai, Sui; Wu, Xiayi; Zhang, Hanqing; Qiao, Wei; Luo, Xin; Chen, Zhuofan

    2015-06-01

    Biological hydroxyapatite, derived from animal bones, is the most widely used bone substitute in orthopedic and dental treatments. Fluorine is the trace element involved in bone remodeling and has been confirmed to promote osteogenesis when administered at the appropriate dose. To take advantage of this knowledge, fluorinated porcine hydroxyapatite (FPHA) incorporating increasing levels of fluoride was derived from cancellous porcine bone through straightforward chemical and thermal treatments. Physiochemical characteristics, including crystalline phases, functional groups and dissolution behavior, were investigated on this novel FPHA. Human osteoblast-like MG63 cells were cultured on the FPHA to examine cell attachment, cytoskeleton, proliferation and osteoblastic differentiation for in vitro cellular evaluation. Results suggest that fluoride ions released from the FPHA play a significant role in stimulating osteoblastic activity in vitro, and appropriate level of fluoridation (1.5 to 3.1 atomic percents of fluorine) for the FPHA could be selected with high potential for use as a bone substitute.

  6. Platelets promote osteosarcoma cell growth through activation of the platelet-derived growth factor receptor-Akt signaling axis

    PubMed Central

    Takagi, Satoshi; Takemoto, Ai; Takami, Miho; Oh-hara, Tomoko; Fujita, Naoya

    2014-01-01

    The interactions of tumor cells with platelets contribute to the progression of tumor malignancy, and the expression levels of platelet aggregation-inducing factors positively correlate with the metastatic potential of osteosarcoma cells. However, it is unclear how tumor-platelet interaction contributes to the proliferation of osteosarcomas. We report here that osteosarcoma-platelet interactions induce the release of platelet-derived growth factor (PDGF) from platelets, which promotes the proliferation of osteosarcomas. Co-culture of platelets with MG63 or HOS osteosarcoma cells, which could induce platelet aggregation, enhanced the proliferation of each cell line in vitro. Analysis of phospho-antibody arrays revealed that co-culture of MG63 cells with platelets induced the phosphorylation of platelet derived growth factor receptor (PDGFR) and Akt. The addition of supernatants of osteosarcoma-platelet reactants also increased the growth of MG63 and HOS cells as well as the level of phosphorylated-PDGFR and -Akt. Sunitinib or LY294002, but not erlotinib, significantly inhibited the platelet-induced proliferation of osteosarcoma cells, indicating that PDGF released from platelets plays an important role in the proliferation of osteosarcomas by activating the PDGFR and then Akt. Our results suggest that inhibitors that specifically target osteosarcoma-platelet interactions may eradicate osteosarcomas. PMID:24974736

  7. Pirarubicin inhibits multidrug-resistant osteosarcoma cell proliferation through induction of G2/M phase cell cycle arrest

    PubMed Central

    Zheng, Shui-er; Xiong, Sang; Lin, Feng; Qiao, Guang-lei; Feng, Tao; Shen, Zan; Min, Da-liu; Zhang, Chun-ling; Yao, Yang

    2012-01-01

    Aim: Pirarubicin (THP) is recently found to be effective in treating patients with advanced, relapsed or recurrent high-grade osteosarcoma. In this study, the effects of THP on the multidrug-resistant (MDR) osteosarcoma cells were assessed, and the underlying mechanisms for the disruption of cell cycle kinetics by THP were explored. Methods: Human osteosarcoma cell line MG63 and human MDR osteosarcoma cell line MG63/DOX were tested. The cytotoxicity of drugs was examined using a cell proliferation assay with the Cell Counting Kit-8 (CCK-8). The distribution of cells across the cell cycle was determined with flow cytometry. The expression of cell cycle-regulated genes cyclin B1 and Cdc2 (CDK1), and the phosphorylated Cdc2 and Cdc25C was examined using Western blot analyses. Results: MG63/DOX cells were highly resistant to doxorubicin (ADM) and gemcitabine (GEM), but were sensitive or lowly resistant to THP, methotrexate (MTX) and cisplatin (DDP). Treatment of MG63/DOX cells with THP (200–1000 ng/mL) inhibited the cell proliferation in time- and concentration-dependent manners. THP (50–500 ng/mL) induced MG63/DOX cell cycle arrest at the G2/M phase in time- and concentration-dependent manners. Furthermore, the treatment of MG63/DOX cells with THP (200–1000 ng/mL) downregulated cyclin B1 expression, and decreased the phosphorylated Cdc2 at Thr161. Conversely, the treatment increased the phosphorylated Cdc2 at Thr14/Tyr15 and Cdc25C at Ser216, which led to a decrease in Cdc2-cyclin B1 activity. Conclusion: The cytotoxicity of THP to MG63/DOX cells may be in part due to its ability to arrest cell cycle progression at the G2/M phase, which supports the use of THP for managing patients with MDR osteosarcoma. PMID:22580740

  8. Sanguinarine induces apoptosis of human osteosarcoma cells through the extrinsic and intrinsic pathways

    SciTech Connect

    Park, Hyunjin; Bergeron, Eric; Senta, Helena; Guillemette, Kim; Beauvais, Sabrina; Blouin, Richard; Sirois, Joel; Faucheux, Nathalie

    2010-08-27

    Research highlights: {yields} We show for the first time the effect of sanguinarine (SA) on MG63 and SaOS-2 cells. {yields} SA altered osteosarcoma cell viability in a concentration and time dependent manner. {yields} SA induced osteosarcoma cell apoptosis and increased caspase-8 and -9 activities. {yields} SA decreased dose dependently the Bcl-2 protein level only in MG63 cells. {yields} SaOS-2 which are osteoblast-derived, seemed more resistant to SA than MG63. -- Abstract: The quaternary benzo[c]phenanthridine alkaloid sanguinarine inhibits the proliferation of cancerous cells from different origins, including lung, breast, pancreatic and colon, but nothing is known of its effects on osteosarcoma, a primary malignant bone tumour. We have found that sanguinarine alters the morphology and reduces the viability of MG-63 and SaOS-2 human osteosarcoma cell lines in concentration- and time-dependent manner. Incubation with 1 {mu}mol/L sanguinarine for 4 and 24 h killed more efficiently MG-63 cells than SaOS-2 cells, while incubation with 5 {mu}mol/L sanguinarine killed almost 100% of both cell populations within 24 h. This treatment also changed the mitochondrial membrane potential in both MG-63 and SaOS-2 cells within 1 h, caused chromatin condensation and the formation of apoptotic bodies. It activated multicaspases, and increased the activities of caspase-8 and caspase-9 in both MG-63 and SaOS-2 cells. These data highlight sanguinarine as a novel potential agent for bone cancer therapy.

  9. Surface modification of parylene-N films for the culture of osteoblast-like cells (MG-63)

    NASA Astrophysics Data System (ADS)

    Liaqat, Usman; Ko, Hyuk; Suh, Hwal; Lee, Misu; Pyun, Jae-Chul

    2016-08-01

    The influence of microenvironments on the culture of osteoblast-like cells (MG-63) has been investigated using parylene films with different surfaces, such as parylene-N film, UV-modified parylene-N film, functional parylene film with amine groups (parylene-A), and UV-modified parylene-A film. In this work, parylene-N film was found to induce dramatic changes in cell adhesion and cell viability before and after UV-treatment with respect to the culture of osteoblast-like cells (MG-63). The influences of such a chemical environment on cell culture were investigated in relation to the cell proliferation (viability and proliferation rate) and the cell physiology (cell cycle, protein synthesis, and differentiation) of cells grown on parylene-N film, UV-modified parylene-N film, parylene-A film, and UV-modified parylene-A film in comparison with cells grown on a polystyrene surface.

  10. Triptolide induces the cell apoptosis of osteosarcoma cells through the TRAIL pathway.

    PubMed

    Zhao, Xingwei; Zhang, Qiang; Chen, Liang

    2016-09-01

    Research on triptolide, a diterpenoid epoxide found in the Thunder God Vine Tripterygium wilfordii, has increased our knowledge of the pharmacology, pharmacokinetics, toxicology and clinical application of this agent. In the present study, we aimed to identify the effects of triptolide on the apoptosis of osteosarcoma cells and to evaluate the anti-proliferative action of this agent. MG-63 cells were treated either with various doses of triptolide (50, 100 or 200 nM) or DMSO for 6, 12 and 24 h. Treatment with triptolide effectively suppressed the cell viability and induced the apoptosis of osteosarcoma MG-63 cells as detected by MTT assay and flow cytometry, respectively. In addition, by using caspase-3, caspase-8 and caspase-9 activity assays and western blot analysis, the anticancer effects of triptolide against osteosarcoma growth were found to involve activation of the DR-5/p53/Bax/caspase-9/ caspase-3 signaling pathway and the DR-5/FADD/caspase-8/lysosomal/cathepsin B/caspase-3 signaling pathway in the MG-63 cells. An important factor in the anticancer effects of triptolide against osteosarcoma was TRAIL-DR-5. The data suggest that triptolide may be a potential novel chemotherapeutic agent for osteosarcoma and acts through the TRAIL-DR-5 signaling pathway. PMID:27461934

  11. Characterization of cadmium uptake and cytotoxicity in human osteoblast-like MG-63 cells

    SciTech Connect

    Levesque, Martine; Martineau, Corine; Jumarie, Catherine; Moreau, Robert

    2008-09-15

    Since bone mass is maintained constant by the balance between osteoclastic bone resorption and osteoblastic bone formation, alterations in osteoblast proliferation and differentiation may disturb the equilibrium of bone remodeling. Exposure to cadmium (Cd) has been associated with the alteration of bone metabolism and the development of osteoporosis. Because little information is available about the direct effects of Cd on osteoblastic cells, we have characterized in vitro the cellular accumulation and cytotoxicity of Cd in human osteoblastic cells. Incubation of osteoblast-like MG-63 cells with increasing concentrations of Cd in serum-free culture medium reduced cell viability in a time- and concentration-dependent manner, suggesting that Cd accumulates in osteoblasts. Consequently, an uptake time-course could be characterized for the cellular accumulation of {sup 109}Cd in serum-free culture medium. In order to characterize the mechanisms of Cd uptake, experiments have been conducted under well-defined metal speciation conditions in chloride and nitrate transport media. The results revealed a preferential uptake of Cd{sup 2+} species. The cellular accumulation and cytotoxicity of Cd increased in the absence of extracellular calcium (Ca), suggesting that Cd may enter the cells in part through Ca channels. However, neither the cellular accumulation nor the cytotoxicity of Cd was modified by voltage-dependent Ca channel (VDCC) modulators or potassium-induced depolarization. Moreover, exposure conditions activating or inhibiting capacitative Ca entry (CCE) failed to modify the cellular accumulation and cytotoxicity of Cd, which excludes the involvement of canonical transient receptor potential (TRPC) channels. The cellular accumulation and cytotoxicity of Cd were reduced by 2-APB, a known inhibitor of the Mg and Ca channel TRPM7 and were increased in the absence of extracellular magnesium (Mg). The inhibition of Cd uptake by Mg and Ca was not additive, suggesting

  12. Niclosamide inhibits the proliferation of human osteosarcoma cell lines by inducing apoptosis and cell cycle arrest.

    PubMed

    Li, Zonghuan; Yu, Yifeng; Sun, Shaoxing; Qi, Baiwen; Wang, Weiyang; Yu, Aixi

    2015-04-01

    Niclosamide, used as an antihelminthic, has demonstrated some properties of anticancer effects. However, its role in osteosarcoma remains to be determined. The aim of this study was to determine the effect of niclosamide on human osteosarcoma cell lines. The human MG-63 and U2OS osteosarcoma cell lines were treated with different concentrations of niclosamide. The cell inhibitory rate was calculated by CCK-8 assay. Cell cycle was detected by flow cytometry. Cell apoptosis was determined by Hoechst 33324 staining, flow cytometry and fluorescence microscope, respectively. The expression of bcl-2, bax and pro-caspase-3 were measured by western blotting. Niclosamide exerted an inhibitory effect on the two cell lines in a time- and dose-dependent manner. Niclosamide was found to induce the arrest of S and G2/M phase in U2OS cells and G2/M in MG-63 cells. Moreover, niclosamide induced apoptosis in MG-63 and U2OS cells. The bax/bcl-2 ratio increased while the expression of pro‑caspase-3 decreased significantly in the two cell lines. The results indicated that niclosamide inhibits proliferation, and induces apoptosis and cell cycle arrest in human osteosarcoma cell lines. PMID:25634333

  13. mTOR Signal Transduction Pathways Contribute to TN-C FNIII A1 Overexpression by Mechanical Stress in Osteosarcoma Cells

    PubMed Central

    Zheng, Lianhe; Zhang, Dianzhong; Zhang, Yunfei; Wen, Yanhua; Wang, Yucai

    2014-01-01

    Osteosarcoma is the most common primary malignant bone tumor with a very poor prognosis. Treating osteosarcoma remains a challenge due to its high transitivity. Tenascin-C, with large molecular weight variants including different combinations of its alternative spliced FNIII repeats, is specifically over expressed in tumor tissues. This study examined the expression of Tenascin-C FNIIIA1 in osteosarcoma tissues, and estimated the effect of mechanical stimulation on A1 expression in MG-63 cells. Through immunohistochemical analysis, we found that the A1 protein was expressed at a higher level in osteosarcoma tissues than in adjacent normal tissues. By cell migration assay, we observed that there was a significant correlation between A1 expression and MG-63 cell migra-tion. The relation is that Tenascin-C FNIIIA1 can promote MG-63 cell migration. According to our further study into the effect of mechanical stimulation on A1 expression in MG-63 cells, the mRNA and protein levels of A1 were significantly up-regulated under mechanical stress with the mTOR molecule proving indispensable. Meanwhile, 4E-BP1 and S6K1 (downstream molecule of mTOR) are necessary for A1 normal expression in MG-63 cells whether or not mechanical stress has been encountered. We found that Tenascin-C FNIIIA1 is over-expressed in osteosar-coma tissues and can promote MG-63 cell migration. Furthermore, mechanical stress can facilitate MG-63 cell migration though facilitating A1 overexpression with the necessary molecules (mTOR, 4E-BP1 and S6K1). In con-clusion, high expression of A1 may promote the meta-stasis of osteosarcoma by facilitating MG-63 cell migration. Tenascin-C FNIIIA1 could be used as an indicator in metastatic osteosarcoma patients. PMID:24598996

  14. St. John's Wort (Hypericum perforatum) stimulates human osteoblastic MG-63 cell proliferation and attenuates trabecular bone loss induced by ovariectomy

    PubMed Central

    You, Mi-kyoung; Kim, Du-Woon; Jeong, Kyu-Shik; Bang, Mi-Ae; Kim, Hwan-Seon; Rhuy, Jin

    2015-01-01

    BACKGROUND/OBJECFTIVES The effect of St. John's Wort extract (SJW) on MG-63 cell proliferation and trabecular bone loss induced by ovariectomy was examined. MATERIALS/METHODS Proliferation, expression of estrogen receptor (ER) α and ER β, and gene expressions of osteoprotegerin (OPG), osteocalcin (OC) and alkaline phosphatase (ALP) were examined in MG-63 cells treated with or without SJW. Ovariectomized rats were treated with SJW at the dose of 100 or 200 mg/kg/day, β-estradiol-3-benzoate (E2), or vehicle only (OVX-C), and sham operated rats were treated with vehicle only (Sham-C). Serum ALP and C-telopeptide (CTX), and femoral trabecular bone loss were examined. RESULTS SJW increased MG-63 cell proliferation and expression of ER α and ER β, and positive effect was shown on gene expressions of ALP, OC and OPG. SJW also showed estrogen like effect on bone associated with slowing down in trabecular bone loss. Histopathology by H&E showed rats treated with SJW displayed denser structure in metaphyseal region of distal femur compared with rats in OVX-C. SJW was shown to reduce serum CTX in OVX rats. CONCLUSION The present study provides new insight in preventing estrogen deficiency induced bone loss of SJW and possibility for its application in bone health supplement. PMID:26425274

  15. Triptolide reduces the viability of osteosarcoma cells by reducing MKP-1 and Hsp70 expression

    PubMed Central

    ZHAO, LEI; JIANG, BO; WANG, DONG; LIU, WEI; ZHANG, HUAWU; LIU, WEISHENG; QIU, ZHEN

    2016-01-01

    Osteosarcoma is the most common type of malignant bone tumor found in adolescents and young adults. The aim of the present study was to determine whether triptolide, a diterpene epoxide extracted from the Tripterygium plant, was able effectively decrease the viability of osteosarcoma cells. The underlying molecular mechanisms are also investigated. The human osteosarcoma cell lines U-2 OS and MG-63 were used in this study. The U-2 OS and MG-63 cells were treated with 0, 5, 10, 25 or 50 nM triptolide. Cells treated with dimethyl sulfoxide only were used as the no drug treatment control. A commercial MTT kit was used to determine the effects of triptolide on cells. Mitogen-activated protein kinase phosphatase-1 (MKP-1) is frequently overexpressed in tumor tissues, possibly related to the failure of a number of chemotherapeutics. Heat shock protein 70 (Hsp70) is a chaperone molecule that is able to increase drug resistance. The protein expression levels of MKP-1 and Hsp70 were determined using western blot analysis. The results indicate that triptolide effectively reduced the viability of the osteosarcoma cells. Furthermore, triptolide was found to effectively reduce MKP-1 expression and Hsp70 levels. Further analysis showed that triptolide reduced MKP-1 mRNA expression in the U-2 OS and MG-63 cells. Triptolide reduced Hsp70 mRNA expression levels in U-2 OS and MG-63 cells. These results suggest that triptolide effectively decreases the viability of osteosarcoma cells. These effects may be associated with the decreased expression of MKP-1 and Hsp70 levels. These results suggest that triptolide may be used in the treatments of osteosarcoma. PMID:27168842

  16. In vitro effect of mineralized and demineralized bone allografts on proliferation and differentiation of MG-63 osteoblast-like cells.

    PubMed

    Lafzi, Ardeshir; Vahabi, Surena; Ghods, Shadab; Torshabi, Maryam

    2016-03-01

    Due to the extensive use of bone allografts in bone reconstruction and periodontal therapy as suitable alternatives to autografts, they are now marketed under different commercial brands. Considering the controversial reports regarding the osteoinductive properties of bone allografts, this study sought to assess the effect of type (mineralized/demineralized), amount and particle size of several allografts on the proliferation and differentiation of MG-63 osteoblast-like cells. MG-63 cells (24-h culture) were exposed to 20 and 40 mg amounts of nine different commercially available freeze-dried bone allografts. After 24 and 72 h of incubation, the effect of water-soluble allograft released materials on cell viability and proliferation was assessed using methyl thiazol tetrazolium (MTT) assay after 24 and 72 h of exposure. Cell differentiation and mineralization was assessed by real-time quantitative reverse transcription PCR and alizarin red staining after 72 h of exposure. The amount and particle size of understudy allografts had significant effects on cell viability after 24 h of exposure (in contrast to 72 h). Higher rate of proliferation was seen in non-differentiated or slow-differentiated groups. The amount and particle size factors had no significant effect on the amount of calcified nodules or the expression of osteogenic marker genes in most groups. Faster and more distinct differentiation and mineralization was noted in mineralized compared to demineralized groups during the 3-day study period. Based on the results, the understudy mineralized (non-demineralized) bone allografts had greater effect on osteogenic differentiation of the MG-63 cells and showed more in vitro osteoinductive activity compared to partially demineralized and fully demineralized types. PMID:26084504

  17. Hyperoside, a flavonoid compound, inhibits proliferation and stimulates osteogenic differentiation of human osteosarcoma cells.

    PubMed

    Zhang, Ning; Ying, Mei-Dan; Wu, Yong-Ping; Zhou, Zhi-Hong; Ye, Zhao-Ming; Li, Hang; Lin, Ding-Sheng

    2014-01-01

    Osteosarcoma, one of the most common malignant bone tumours, is generally considered a differentiation disease caused by genetic and epigenetic disruptions in the terminal differentiation of osteoblasts. Novel therapies based on the non-cytotoxic induction of cell differentiation-responsive pathways could represent a significant advance in treating osteosarcoma; however, effective pharmaceuticals to induce differentiation are lacking. In the present study, we investigated the effect of hyperoside, a flavonoid compound, on the osteoblastic differentiation of U2OS and MG63 osteosarcoma cells in vitro. Our results demonstrated that hyperoside inhibits the proliferation of osteosarcoma cells by inducing G0/G1 arrest in the cell cycle, without causing obvious cell death. Cell migration assay further suggested that hyperoside could inhibit the invasion potential of osteosarcoma cells. Additionally, osteopontin and runt-related transcription factor 2 protein levels and osteocalcin activation were upregulated dramatically in hyperoside-treated osteosarcoma cells, suggesting that hyperoside may stimulates osteoblastic differentiation in osteosarcoma cells. This differentiation was accompanied by the activation of transforming growth factor (TGF)-β and bone morphogenetic protein-2, suggesting that the hyperoside-induced differentiation involves the TGF-β signalling pathway. To our knowledge, this study is the first to evaluate the differentiation effect of hyperoside in osteosarcoma cells and assess the possible potential for hyperoside treatment as a future therapeutic approach for osteosarcoma differentiation therapy. PMID:24983940

  18. A Comparative Study on Root Canal Repair Materials: A Cytocompatibility Assessment in L929 and MG63 Cells

    PubMed Central

    Jiang, Yuqing; Zheng, Qinghua; Zhou, Xuedong; Gao, Yuan; Huang, Dingming

    2014-01-01

    Cytocompatibility of repair materials plays a significant role in the success of root canal repair. We conducted a comparative study on the cytocompatibility among iRoot BP Plus, iRoot FS, ProRoot MTA, and Super-EBA in L929 cells and MG63 cells. The results revealed that iRoot FS was able to completely solidify within 1 hour. iRoot BP Plus required 7-day incubation, which was much longer than expected (2 hours), to completely set. ProRoot MTA and Super-EBA exhibited a similar setting duration of 12 hours. All the materials except Super-EBA possessed negligible in vitro cytotoxicity. iRoot FS had the best cell adhesion capacity in both L929 and MG63 cells. With rapid setting, negligible cytotoxicity, and enhanced cell adhesion capacity, iRoot FS demonstrated great potential in clinical applications. Future work should focus on longer-term in vitro cytocompatibility and an in vivo assessment. PMID:24526893

  19. Transforming growth factor beta (TGF-β) isomers influence cell detachment of MG-63 bone cells.

    PubMed

    Sefat, Farshid; Khaghani, Seyed Ali; Nejatian, Touraj; Genedy, Mohammed; Abdeldayem, Ali; Moghaddam, Zoha Salehi; Denyer, Morgan C T; Youseffi, Mansour

    2015-12-01

    Bone repair and wound healing are modulated by different stimuli. There is evidence that Transforming Growth Factor-beta (TGF-β) super-family of cytokines have significant effects on bone structure by regulating the replication and differentiation of chondrocytes, osteoblasts and osteoclasts. There is also significant evidence that interactions with extracellular matrix molecules influence cell behaviour. In this study cell surface attachment was examined via a trypsinization assay using various TGF-β isomers in which the time taken to trypsinize cells from the surface provided a means of assessing the strength of attachment. Three TGF-β isomers (TGF-β1, 2 and 3), four combined forms (TGF-β(1+2), TGF-β(1+3), TGF-β(2+3) and TGF-β(1+2+3)) along with four different controls (BSA, HCl, BSA/HCl and negative control) were investigated in this study. The results indicated that treatment with TGF-β1, 2, 3 and HCl decreased cell attachment, however, this effect was significantly greater in the case of TGF-β3 (p<0.001) indicating perhaps that TGF-β3 does not act alone in cell detachment, but instead functions synergistically with signalling pathways that are dependent on the availability of hydrogen ions. Widefield Surface Plasmon Resonance (WSPR) microscope was also used to investigate cell surface interactions. PMID:26372305

  20. TRIM59 is upregulated and promotes cell proliferation and migration in human osteosarcoma.

    PubMed

    Liang, Jinqian; Xing, Dan; Li, Zheng; Shen, Jianxiong; Zhao, Hong; Li, Shugang

    2016-06-01

    Osteosarcoma is a prevalent type of cancer and has a high metastatic ability, particularly for metastasis to the lungs. Effective treatment strategies have improved, however, the detailed molecular mechanism underlying the onset of this malignancy remains to be fully elucidated. The current study investigated the role of the tripartite motif (TRIM) family protein TRIM59 in osteosarcoma growth and metastasis. It was identified that TRIM59 was overexpressed in clinical osteosarcoma tissues and cultured osteosarcoma cell lines. In addition, the MTT assay demonstrated that in U2OS and MG63 cells, knockdown of TRIM59 by specific siRNA inhibited proliferation, whereas overexpression of TRIM59 promoted cell proliferation. Furthermore, overexpression of TRIM59 significantly increased the U2OS cell migrative and invasive abilities in a Transwell chamber assay. In addition, TRIM59 was able to negatively regulate the protein levels of P53 without significantly affecting the mRNA levels in U2OS and MG63 cells. These data suggest the oncogenic abilities of TRIM59 in osteosarcoma, which promote osteosarcoma cell proliferation, migration and invasion. PMID:27121462

  1. Impact of silk fibroin-based scaffold structures on human osteoblast MG63 cell attachment and proliferation

    PubMed Central

    Varkey, Aneesia; Venugopal, Elakkiya; Sugumaran, Ponjanani; Janarthanan, Gopinathan; Pillai, Mamatha M; Rajendran, Selvakumar; Bhattacharyya, Amitava

    2015-01-01

    The present study was carried out to investigate the impact of various types of silk fibroin (SF) scaffolds on human osteoblast-like cell (MG63) attachment and proliferation. SF was isolated from Bombyx mori silk worm cocoons after degumming. Protein concentration in the degummed SF solution was estimated using Bradford method. Aqueous SF solution was used to fabricate three different types of scaffolds, viz, electrospun nanofiber mat, sponge, and porous film. The structures of the prepared scaffolds were characterized using optical microscopy and field emission scanning electron microscopy. The changes in the secondary structure of the proteins and the thermal behavior of the scaffolds were determined by Fourier transform infrared spectroscopy and thermo-gravimetric analysis, respectively. The biodegradation rate of scaffolds was determined by incubating the scaffolds in simulated body fluid for 4 weeks. MG63 cells were seeded on the scaffolds and their attachment and proliferation onto the scaffolds were studied. The MTT assay was carried out to deduce the toxicity of the developed scaffolds. All the scaffolds were found to be biocompatible. The amount of collagen produced by the osteoblast-like cells growing on different scaffolds was estimated. PMID:26491306

  2. The Cancer-Related Transcription Factor Runx2 Modulates Cell Proliferation in Human Osteosarcoma Cell Lines

    PubMed Central

    Lucero, Claudia M.J.; Vega, Oscar A.; Osorio, Mariana M.; Tapia, Julio C.; Antonelli, Marcelo; Stein, Gary S.; Van Wijnen, Andre J.; Galindo, Mario A.

    2013-01-01

    Runx2 regulates osteogenic differentiation and bone formation, but also suppresses pre-osteoblast proliferation by affecting cell cycle progression in the G1 phase. The growth suppressive potential of Runx2 is normally inactivated in part by protein destabilization, which permits cell cycle progression beyond the G1/S phase transition, and Runx2 is again up-regulated after mitosis. Runx2 expression also correlates with metastasis and poor chemotherapy response in osteosarcoma. Here we show that six human osteosarcoma cell lines (SaOS, MG63, U2OS, HOS, G292, and 143B) have different growth rates, which is consistent with differences in the lengths of the cell cycle. Runx2 protein levels are cell cycle-regulated with respect to the G1/S phase transition in U2OS, HOS, G292, and 143B cells. In contrast, Runx2 protein levels are constitutively expressed during the cell cycle in SaOS and MG63 cells. Forced expression of Runx2 suppresses growth in all cell lines indicating that accumulation of Runx2 in excess of its pre-established levels in a given cell type triggers one or more anti-proliferative pathways in osteosarcoma cells. Thus, regulatory mechanisms controlling Runx2 expression in osteosarcoma cells must balance Runx2 protein levels to promote its putative oncogenic functions, while avoiding suppression of bone tumor growth. PMID:22949168

  3. TIMP3 regulates osteosarcoma cell migration, invasion, and chemotherapeutic resistances.

    PubMed

    Han, Xiu-Guo; Li, Yan; Mo, Hui-Min; Li, Kang; Lin, Du; Zhao, Chang-Qing; Zhao, Jie; Tang, Ting-Ting

    2016-07-01

    Tissue inhibitors of metalloproteinases (TIMPs) inhibit matrix metalloproteinases (MMPs) to limit degradation of the extracellular matrix. Low levels of TIMP3 have been demonstrated in cancer tissues at advanced clinical stages, with positive distant metastasis and chemotherapeutic resistance. We examined the role of TIMP3 in osteosarcoma (OS) cell invasiveness and chemoresistance. TIMP3 was overexpressed or knocked down in the human OS cell lines Saos2 and MG63. Cell migration and invasion capacities were then evaluated using Transwell assays, and resistance to cisplatin was assessed by CCK-8 assay and flow cytometry. Real-time PCR and western blotting were used to investigate activation of signaling pathways downstream of TIMP3. Overexpression of TIMP3 inhibited the migration and invasion of Saos2 and MG63 cells, while knockdown of TIMP3 had the opposite effect. Cell survival after exposure to cisplatin was inhibited by TIMP3 overexpression in both Saos2 and MG63 cells. Consistently, downregulation of TIMP3 gene expression significantly decreased the sensitivity of OS cells to cisplatin treatment. MMP1, MMP2, Bcl-2, and Akt1 were all downregulated following TIMP3 overexpression, while Bax and cleaved caspase-3 were upregulated. TIMP3 knockdown had opposite effects on the regulation of these genes. Taken together, our findings suggest TIMP3 as a new target for inhibition of OS progression and chemotherapeutic resistance. PMID:26749283

  4. Ursolic Acid Triggers Apoptosis in Human Osteosarcoma Cells via Caspase Activation and the ERK1/2 MAPK Pathway.

    PubMed

    Wu, Chia-Chieh; Cheng, Chun-Hsiang; Lee, Yi-Hui; Chang, Ing-Lin; Chen, Hsin-Yao; Hsieh, Chen-Pu; Chueh, Pin-Ju

    2016-06-01

    Ursolic acid (UA), a naturally occurring pentacyclic triterpene acid found in many medicinal herbs and edible plants, has been shown to trigger apoptosis in several lines of tumor cells in vitro. We found that treatment with UA suppressed the viability of human osteosarcoma MG-63 cells and induced cell cycle arrest at sub-G1 and G2/M phases. Furthermore, exposure to UA induced intracellular oxidative stress and collapse of mitochondrial membrane permeability, resulting in the subsequent activation of apoptotic caspases 8, 9, and 3 as well as PARP cleavage, and ultimately apoptosis in MG-63 cells. Moreover, protein analysis of mitogen-activated protein kinase (MAPK)-related protein expression showed an increase in activated ERK1/2, JNK, and p38 MAPK in UA-treated MG-63 cells. In addition, UA-induced apoptosis was significantly abolished in MG-63 cells that had been pretreated with inhibitors of caspase 3, 8, and 9 and ERK1/2. Furthermore, UA-treated MG-63 cells also exhibited an enhancement in Bax/Bcl-2 ratio, whereas anti-apoptotic XIAP and survivin were down-regulated. Taken together, we provide evidence demonstrating that UA mediates caspase-dependent and ERK1/2 MAPK-associated apoptosis in osteosarcoma MG-63 cells. PMID:27171502

  5. Enhanced proliferation and osteocalcin production by human osteoblast-like MG63 cells on silicon nitride ceramic discs.

    PubMed

    Kue, R; Sohrabi, A; Nagle, D; Frondoza, C; Hungerford, D

    1999-07-01

    The biocompatibility of silicon nitride (Si3N4) was assessed in an in vitro model using the human osteoblast-like MG-63 cell line. Cells were propagated on the surface of: reaction-bonded silicon nitride discs, sintered after reaction-bonded silicon nitride discs or control polystyrene surface for 48 h. Compared to cells propagated on polystyrene surface, cells grown on the surface of unpolished silicon nitride discs had significantly lower cell yield and decreased osteocalcin production. In contrast, cells on the surface of polished silicon nitride discs showed similar proliferative capacity to control cells propagated on polystyrene surface. Cells propagated on polished discs also produced higher levels of osteocalcin than cells on unpolished discs. SEM analysis showed cells with well-delineated morphology and cytoplasmic extensions when propagated on polished sintered after reaction-bonded discs. Cells appeared more spherical, when grown on polished reaction-bonded discs. The results of this study suggest that silicon nitride is a non-toxic, biocompatible ceramic surface for the propagation of functional human bone cells in vitro. Its high wear resistance and ability to support bone cell growth and metabolism make silicone nitride an attractive candidate for clinical application. Further studies are needed to explore the feasibility of using silicon nitride clinically as an orthopedic biomaterial. PMID:10395388

  6. A Comparison between Cytotoxicity Induced by Two Resin Based Sealers (2Seal and AH Plus) in Saos-2 and MG-63 Cell Lines

    PubMed Central

    Ehsani, Maryam; Zabihi, Ebrahim; Gharouee, Hamed

    2012-01-01

    The aim of this study was to evaluate and compare the cytotoxicity induced by two resin-based sealers, 2Seal and AH Plus, in two osteoblast-like cell lines, MG-63 and Saos-2. Using sterile discs of both sealers in complete media, 24- and 72-h extracts were prepared. The extracts were exchanged with Saos-2 or MG-63 cell culture media at 75% confluence, and after 24 h incubation, cell viability tests were performed for each extract and cell line using MTT and trypan blue dye exclusion assays. Corresponding incubated media were used as negative control groups. For both extracts and sealers, cytotoxicity was observed in both cell lines. For Saos-2, there was no statistical difference in toxicity between the sealers for either extract (p > 0.05). For MG-63, the 2Seal 24-h extract and the AH Plus 72-h extract had greater cytotoxicity than the other extracts (p < 0.05(. Both AH Plus and 2Seal demonstrated significant cytotoxicity in these two cell lines. In contrast to 2Seal, the cytotoxicity of AH Plus in the MG-63 cell line increased with extraction time from 24 to 72 h. The AH Plus and 2Seal 24-h extracts showed different levels of cytotoxicity in the MG-63 cell line, while in the Saos-2 cell line there were no detectable differences. This may reflect higher sensitivity of the MG-63 cell line compared to Saos-2 toward cytotoxicity induced by these two sealers, or different kinetics of toxicant release from the sealers. PMID:24551778

  7. Influence of surfaces modified with biomimetic extracellular matrices on adhesion and proliferation of mesenchymal stem cells and osteosarcoma cells.

    PubMed

    Cai, Rong; Kawazoe, Naoki; Chen, Guoping

    2015-02-01

    Preparation of surfaces modified with biomimetic extracellular matrices (ECMs) is important for investigation of the interaction between ECMs and cells. In the present study, surfaces modified with ECMs from normal somatic cells, stem cells and tumor cells were prepared by cell culture method. The ECMs derived from bone marrow-derived mesenchymal stem cells (MSCs), dermal fibroblasts (FBs), osteoblasts (OBs) and MG63 osteosarcoma cells were deposited on the surfaces of cell-culture polystyrene plates (TCPS). The ECMs from different cell types had different compositions. The effects of the ECM-deposited surfaces on the adhesion, spreading and proliferation of MSCs and MG63 human osteosarcoma cells were dependent on the type of both ECMs and cells. The surfaces deposited with ECMs from MSCs, FBs and OBs promoted cell adhesion more strongly than surfaces deposited with ECMs from MG63 cells and TCPS. Compared to TCPS, the ECM-deposited surfaces promoted proliferation of MSCs while they inhibited the proliferation of MG63 cells. PMID:25516267

  8. Hypoxia promotes drug resistance in osteosarcoma cells via activating AMP-activated protein kinase (AMPK) signaling

    PubMed Central

    Zhao, Changfu; Zhang, Qiao; Yu, Tao; Sun, Shudong; Wang, Wenjun; Liu, Guangyao

    2016-01-01

    Purpose Drug resistance has been recognized to be a major obstacle to the chemotherapy for osteosarcoma. And the potential importance of hypoxia as a target to reverse drug resistance in osteosarcoma has been indicated, though the mechanism underlining such role is not clarified. The present study aims to investigate the role of hypoxia in the drug resistance in osteosarcoma cells via activating AMP-activated protein kinase (AMPK) signaling. Experimental design We investigated the promotion of the resistance to doxorubicin of osteosarcoma MG-63 and U2-os cells in vitro, and then determined the role of hypoxia-inducible factor-1 (HIF-1)α and HIF-1β, the activation and regulatory role of AMPK in the osteosarcoma U2-os cells which were treated with doxorubicin under hypoxia. Results It was demonstrated that hypoxia significantly reduced the sensitivity of MG-63 and U2-os cells to doxorubicin, indicating an inhibited viability reduction and a reduced apoptosis promotion. And such reduced sensitivity was not associated with HIF-1α, though it was promoted by hypoxia in U2-os cells. Interestingly, the AMPK signaling was significantly promoted by hypoxia in the doxorubicin-treated U2-os cells, with a marked upregulation of phosphorylated AMPK (Thr 172) and phosphorylated acetyl-CoA carboxylase (ACC) (Ser 79), which were sensitive to the AMPK activator, AICAR and the AMPK inhibitor, Compound C. Moreover, the promoted AMPK activity by AICAR or the downregulated AMPK activity by Compound C significantly reduced or promoted the sensitivity of U2-os cells to doxorubicin. Conclusion The present study confirmed the AMPK signaling activation in the doxorubicin-treated osteosarcoma cells, in response to hypoxia, and the chemical upregulation or downregulation of AMPK signaling reduced or increased the chemo-sensitivity of osteosarcoma U2-os cells in vitro. Our study implies that AMPK inhibition might be a effective strategy to sensitize osteocarcoma cells to chemotherapy. PMID

  9. Serum from patients with ankylosing spondylitis can increase PPARD, fra-1, MMP7, OPG and RANKL expression in MG63 cells

    PubMed Central

    Hu, Zaiying; Lin, Dongfang; Qi, Jun; Qiu, Minli; Lv, Qing; Li, Qiuxia; Lin, Zhiming; Liao, Zetao; Pan, Yunfeng; Jin, Ou; Wu, Yuqiong; Gu, Jieruo

    2015-01-01

    OBJECTIVES: To explore the effects of serum from patients with ankylosing spondylitis on the canonical Wnt/β-catenin pathway and to assess whether the serum has an osteogenic effect in MG63 cells. METHODS: MG63 cells were cultured with serum from 45 ankylosing spondylitis patients, 30 healthy controls, or 45 rheumatoid arthritis patients. The relative PPARD, fra-1, MMP7, OPG and RANKL mRNA levels were measured using quantitative real-time polymerase chain reaction. Associations between gene expression and patient demographics and clinical assessments were then analyzed. RESULTS: MG63 cells treated with serum from ankylosing spondylitis patients had higher PPARD, fra-1, MMP7 and OPG gene expression than did cells treated with serum from controls or rheumatoid arthritis patients (all p<0.05). RANKL expression was higher in MG63 cells treated with serum from patients with ankylosing spondylitis or rheumatoid arthritis than in those treated with serum from controls (both p<0.05). The OPG/RANKL ratio was also higher in MG63 cells treated with serum from ankylosing spondylitis patients than in those treated with serum from controls (p<0.05). No associations were found between the expression of the five genes and the patient demographics and clinical assessments (all p>0.05). CONCLUSIONS : Serum from ankylosing spondylitis patients increases PPARD, fra-1, MMP7, OPG and RANKL expression and the OPG/RANKL ratio in MG63 cells; these effects may be due to the stimulatory effect of the serum on the Wnt pathway. PMID:26602520

  10. Phyllostachys edulis extract induces apoptosis signaling in osteosarcoma cells, associated with AMPK activation

    PubMed Central

    Chou, Chi-Wen; Cheng, Ya-Wen; Tsai, Chung-Hung

    2014-01-01

    Objective Bamboo is distributed worldwide, and its different parts are used as foods or as a traditional herb. Recently, antitumoral effects of bamboo extracts on several tumors have been increasingly reported; however, antitumoral activity of bamboo extracts on osteosarcoma remains unclear. In the present study, we investigated effects of an aqueous Phyllostachys edulis leaf extract (PEE) on osteosarcoma cells and the underlying mechanism of inhibition. Methods The growth of human osteosarcoma cell lines 143B and MG-63 and lung fibroblast MRC-5 cells was determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Apoptosis was demonstrated using TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay and flow cytometric analysis. Phosphorylation and protein levels were determined by immunoblotting. Results After treatment with PEE, viability of 143B and MG-63 cells was dose-dependently reduced to 36.3%±1.6% of control values, which were similar to AICAR (5-aminoimidazole-4-carboxamide 1-β-D-ribofuranoside) treatments. In parallel, ratios of apoptotic cells and cells in the sub-G1 phase were significantly increased. Further investigation showed that PEE treatments led to activation of caspase cascades and changes of apoptotic mediators Bcl2, Bax, and p53. Consistently, our results revealed that PEE activated adenosine monophosphate-activated protein kinase (AMPK) signaling, and the AMPK activation was associated with the induction of apoptotic signaling. Conclusion Our results indicated that PEE suppressed the growth of 143B and MG-63 cells but moderately affected MRC-5 cells. PEE-induced apoptosis may attribute to AMPK activation and the following activation of apoptotic signaling cascades. These findings revealed that PEE possesses antitumoral activity on human osteosarcoma cells by manipulating AMPK signaling, suggesting that PEE alone or combined with regular antitumor drugs may be beneficial as osteosarcoma

  11. Heterogeneity of osteosarcoma cell lines led to variable responses in reprogramming.

    PubMed

    Choong, Pei Feng; Teh, Hui Xin; Teoh, Hoon Koon; Ong, Han Kiat; Choo, Kong Bung; Sugii, Shigeki; Cheong, Soon Keng; Kamarul, Tunku

    2014-01-01

    Four osteosarcoma cell lines, Saos-2, MG-63, G-292 and U-2 OS, were reprogrammed to pluripotent state using Yamanaka factors retroviral transduction method. Embryonic stem cell (ESC)-like clusters started to appear between 15 to 20 days post transduction. Morphology of the colonies resembled that of ESC colonies with defined border and tightly-packed cells. The reprogrammed sarcomas expressed alkaline phosphatase and pluripotency markers, OCT4, SSEA4, TRA-1-60 and TRA-1-81, as in ESC up to Passage 15. All reprogrammed sarcomas could form embryoid body-like spheres when cultured in suspension in a low attachment dish for up to 10 days. Further testing on the directed differentiation capacity of the reprogrammed sarcomas showed all four reprogrammed sarcoma lines could differentiate into adipocytes while reprogrammed Saos-2-REP, MG-63-REP and G-292-REP could differentiate into osteocytes. Among the 4 osteosarcoma cell lines, U-2 OS reported the highest transduction efficiency but recorded the lowest reprogramming stability under long term culture. Thus, there may be intrinsic differences governing the variable responses of osteosarcoma cell lines towards reprogramming and long term culture effect of the reprogrammed cells. This is a first report to associate intrinsic factors in different osteosarcoma cell lines with variable reprogramming responses and effects on the reprogrammed cells after prolonged culture. PMID:25170299

  12. Support for the initial attachment, growth and differentiation of MG-63 cells: a comparison between nano-size hydroxyapatite and micro-size hydroxyapatite in composites.

    PubMed

    Filová, Elena; Suchý, Tomáš; Sucharda, Zbyněk; Supová, Monika; Zaloudková, Margit; Balík, Karel; Lisá, Věra; Slouf, Miroslav; Bačáková, Lucie

    2014-01-01

    Hydroxyapatite (HA) is considered to be a bioactive material that favorably influences the adhesion, growth, and osteogenic differentiation of osteoblasts. To optimize the cell response on the hydroxyapatite composite, it is desirable to assess the optimum concentration and also the optimum particle size. The aim of our study was to prepare composite materials made of polydimethylsiloxane, polyamide, and nano-sized (N) or micro-sized (M) HA, with an HA content of 0%, 2%, 5%, 10%, 15%, 20%, 25% (v/v) (referred to as N0-N25 or M0-M25), and to evaluate them in vitro in cultures with human osteoblast-like MG-63 cells. For clinical applications, fast osseointegration of the implant into the bone is essential. We observed the greatest initial cell adhesion on composites M10 and N5. Nano-sized HA supported cell growth, especially during the first 3 days of culture. On composites with micro-size HA (2%-15%), MG-63 cells reached the highest densities on day 7. Samples M20 and M25, however, were toxic for MG-63 cells, although these composites supported the production of osteocalcin in these cells. On N2, a higher concentration of osteopontin was found in MG-63 cells. For biomedical applications, the concentration range of 5%-15% (v/v) nano-size or micro-size HA seems to be optimum. PMID:25125978

  13. Support for the initial attachment, growth and differentiation of MG-63 cells: a comparison between nano-size hydroxyapatite and micro-size hydroxyapatite in composites

    PubMed Central

    Filová, Elena; Suchý, Tomáš; Sucharda, Zbyněk; Šupová, Monika; Žaloudková, Margit; Balík, Karel; Lisá, Věra; Šlouf, Miroslav; Bačáková, Lucie

    2014-01-01

    Hydroxyapatite (HA) is considered to be a bioactive material that favorably influences the adhesion, growth, and osteogenic differentiation of osteoblasts. To optimize the cell response on the hydroxyapatite composite, it is desirable to assess the optimum concentration and also the optimum particle size. The aim of our study was to prepare composite materials made of polydimethylsiloxane, polyamide, and nano-sized (N) or micro-sized (M) HA, with an HA content of 0%, 2%, 5%, 10%, 15%, 20%, 25% (v/v) (referred to as N0–N25 or M0–M25), and to evaluate them in vitro in cultures with human osteoblast-like MG-63 cells. For clinical applications, fast osseointegration of the implant into the bone is essential. We observed the greatest initial cell adhesion on composites M10 and N5. Nano-sized HA supported cell growth, especially during the first 3 days of culture. On composites with micro-size HA (2%–15%), MG-63 cells reached the highest densities on day 7. Samples M20 and M25, however, were toxic for MG-63 cells, although these composites supported the production of osteocalcin in these cells. On N2, a higher concentration of osteopontin was found in MG-63 cells. For biomedical applications, the concentration range of 5%–15% (v/v) nano-size or micro-size HA seems to be optimum. PMID:25125978

  14. Study the cytotoxicity of different kinds of water-soluble nanoparticles in human osteoblast-like MG-63 cells

    SciTech Connect

    Niu, Lu; Li, Yang; Li, Xiaojie; Gao, Xue; Su, Xingguang

    2012-11-15

    Highlights: ► Preparation of three kinds of water-soluble QDs: CdTe, CdTe@SiO{sub 2}, Mn:ZnSe. ► Evaluated the cytotoxicity qualitatively and quantitatively. ► Fluorescent staining. ► Detected the total intracellular cadmium in cells. -- Abstract: Quantum nanoparticles have been applied extensively in biological and medical fields, the cytotoxicity of nanoparticles becomes the key point we should concern. In this paper, the cytotoxicity of three kinds of water-soluble nanoparticles: CdTe, CdTe@SiO{sub 2} and Mn:ZnSe was studied. We evaluated the nanoparticles toxicity qualitatively by observing the morphological changes of human osteoblast-like MG-63 cells at different incubation times and colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays were carried out to detect the cell viability quantitatively. The results showed that CdTe nanoparticles with high concentrations caused cells to die largely while CdTe@SiO{sub 2} and Mn:ZnSe nanoparticles had no obvious effect. For further study, we studied the relation between the cell viability and the total cadmium concentration in cells and found that the viability of cells treated with CdTe@SiO{sub 2} nanoparticles was higher than that treated with CdTe nanoparticles. We also discovered that the death rate of cells co-incubated with CdTe nanoparticles was proportional to the total intracellular cadmium concentrations.

  15. Biphasic Response to Luteolin in MG-63 Osteoblast-Like Cells under High Glucose-Induced Oxidative Stress

    PubMed Central

    Abbasi, Naser; Khosravi, Afra; Aidy, Ali; Shafiei, Massoumeh

    2016-01-01

    Background: Clinical evidence indicates the diabetes-induced impairment of osteogenesis caused by a decrease in osteoblast activity. Flavonoids can increase the differentiation and mineralization of osteoblasts in a high-glucose state. However, some flavonoids such as luteolin may have the potential to induce cytotoxicity in osteoblast-like cells. This study was performed to investigate whether a cytoprotective concentration range of luteolin could be separated from a cytotoxic concentration range in human MG-63 osteoblast-like cells in high-glucose condition. Methods: Cells were cultured in a normal- or high-glucose medium. Cell viability was determined with the MTT assay. The formation of intracellular reactive oxygen species (ROS) was measured using probe 2’,7’ -dichlorofluorescein diacetate, and osteogenic differentiation was evaluated with an alkaline phosphatase bioassay. Results: ROS generation, reduction in alkaline phosphatase activity, and cell death induced by high glucose were inhibited by lower concentrations of luteolin (EC50, 1.29±0.23 µM). Oxidative stress mediated by high glucose was also overcome by N-acetyl-L-cysteine. At high concentrations, luteolin caused osteoblast cell death in normal- and high-glucose states (IC50, 34±2.33 and 27±2.42 µM, respectively), as represented by increased ROS and decreased alkaline phosphatase activity. Conclusion: Our results indicated that the cytoprotective action of luteolin in glucotoxic condition was manifested in much lower concentrations, by a factor of approximately 26 and 20, than was its cytotoxic activity, which occurred under normal or glucotoxic condition, respectively. PMID:26989282

  16. Construction of recombinant pEGFP-N1-hPer2 plasmid and its expression in osteosarcoma cells

    PubMed Central

    CHENG, ANYUAN; ZHANG, YAN; MEI, HONGJUN; FANG, SHUO; JI, PENG; YANG, JIAN; YU, LING; GUO, WEICHUN

    2016-01-01

    The aim of this study was to construct the eukaryotic expression vector pEGFP-N1-hPer2 and assess its expression in the human osteosarcoma cell line MG63. Total mRNA was extracted from human osteosarcoma MG63 cells, the human period 2 (hPer2) gene was obtained by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into the pEGFP-N1 vector, then the recombinant pEGFP-N1-hPer2 plasmid was constructed and transfected into MG63 cells using Lipofectamine 2000. The expression of hPer2 in MG63 cells was measured by quantitative RT-PCR and western blot analysis. The accurate construction of pEGFP-N1-hPer2 was verified by double enzyme digestion and DNA sequencing. hPer2 gene expression in the transfected cells was assessed by RT-qPCR and western blot analysis. In conclusion, the recombinant pEGFP-N1-hPer2 plasmid was constructed successfully, and expressed effectively in MG63 cells. PMID:27073550

  17. Matrine-induced autophagy counteracts cell apoptosis via the ERK signaling pathway in osteosarcoma cells

    PubMed Central

    Ma, Kun; Huang, Man-Yu; Guo, Yan-Xing; Hu, Guo-Qiang

    2016-01-01

    The aim of the present study was to observe whether autophagy was induced by matrine, and to investigate the role of autophagy in the antitumor effects of matrine on human osteosarcoma MG-63 cells and its underlying mechanism. MG-63 cells were cultured in vitro in matrine at a concentration of 0.6, 0.8, 1.0 and 1.2 g/l for 0, 24, 48 and 72 h. A MTT assay was used to evaluate the proliferation inhibition of MG-63 cells by matrine, and Annexin V-fluorescein isothiocyanate/propidum iodide (PI) staining flow cytometry was used to analyze the apoptotic rate. Alterations in cell morphology was assessed by PI and Hoechst 33258 cell staining. Matrine-induced autophagy in MG-63 cells was confirmed by green fluorescent protein-microtubule-associated protein 1-light chain 3 (LC3) b transfection and fluorescence microscopy, and cell viability was investigated by MTT assay following inhibition of autophagy by chloroquine (CQ) pretreatment. The expression level of apoptosis-associated proteins B-cell lymphoma-2 (Bcl-2) and Bcl-2-like protein 4 (Bax), autophagy-associated LC3II protein, and the activation of extracellular signal-regulated kinase (ERK) was detected by western blotting. Cell proliferation was clearly inhibited by matrine in a dose- and time-dependent manner. Flow cytometry and Hoechst 33258/PI staining verified that matrine induced apoptosis in a time-dependent manner when cells were exposed to 1.1 g/l matrine; fluorescence microscopy demonstrated that green fluorescence puncta were enhanced with prolonged time of matrine incubation. Western blotting confirmed that the expression of pro-apoptosis-associated proteins Bax and LC3II, and phosphorylated-ERK were upregulated, and anti-apoptosis protein Bcl-2 was downregulated in a time-dependent manner following treatment with matrine. The cell viability of the matrine + CQ group was increased compared with the matrine group alone, which revealed that matrine treatment alone induced protective autophagy in MG-63 cells

  18. A furin inhibitor downregulates osteosarcoma cell migration by downregulating the expression levels of MT1-MMP via the Wnt signaling pathway

    PubMed Central

    LIU, BINGSHAN; LI, GUOJUN; WANG, XIAO; LIU, YANG

    2014-01-01

    This study aimed to explore the exact mechanism of the effect of a furin inhibitor on the migration and invasion of MG-63 and Saos-2 osteosarcoma cells. MG-63 and Saos-2 osteosarcoma cells were treated with regular culture medium in the presence or absence of 480 nM α1-antitrypsin Portland (α1-PDX). Wound-healing and Transwell assays were used for the detection of the effects of α1-PDX on MG-63 and Saos-2 osteosarcoma cell migration and invasion. Western blot analysis and reverse transcription-polymerase chain reaction were performed to detect the expression levels of membrane type I matrix metalloproteinase (MT1-MMP), Wnt and β-catenin. A chromatin immunoprecipitation assay was used for detection of the levels of MT1-MMP gene transcription activity. The results showed that α1-PDX treatment significantly reduced the migration and invasion ability of the cells. Notably, the expression levels of MT1-MMP decreased evidently upon α1-PDX treatment, paralleled with reductions in the expression levels of Wnt and β-catenin. Further analysis of the transcriptional activity of MT1-MMP revealed that the α1-PDX-induced downregulation of the levels of MT1-MMP was mediated by the Wnt signaling pathway. These data suggest that α1-PDX plays a vital role in inhibiting MG-63 and Saos-2 osteosarcoma cell migration and invasion by downregulating the expression levels of MT1-MMP via the Wnt signaling pathway. PMID:24944664

  19. Aloe-emodin-mediated photodynamic therapy induces autophagy and apoptosis in human osteosarcoma cell line MG‑63 through the ROS/JNK signaling pathway.

    PubMed

    Tu, Pinghua; Huang, Qiu; Ou, Yunsheng; Du, Xing; Li, Kaiting; Tao, Yong; Yin, Hang

    2016-06-01

    The present study was carried out to investigate the effect and mechanisms of aloe‑emodin (AE)-mediated photodynamic therapy (AE-PDT) on the human osteosarcoma cell line MG-63. After treatment with AE-PDT, the human osteosarcoma cell line MG-63 was tested for levels of viability, autophagy, reactive oxygen species (ROS) and apoptosis and changes in cell morphology with the Cell Counting Kit-8 (CCK‑8), monodansylcadaverine (MDC) and Hoechst staining and transmission electron microscopy. The expression of proteins including LC-3, cleaved caspase-3, Beclin-1, Bcl-2, p-JNK, t-JNK and β-actin was examined with western blotting. AE-PDT significantly inhibited the viability of the MG-63 cells in an AE-concentration- and PDT energy density-dependent manner. Autophagy and apoptosis of MG-63 cells was substantially promoted in the AE-PDT group compared to the control group, the AE alone group and the light emitting diode (LED) alone group. Inhibition of autophagy by 3-methyladenine (3-MA) (5 mM) and chloroquine (CQ) (15 µM) significantly promoted the apoptosis rate and improved the sensitivity of the MG-63 cells to AE-PDT. AE-PDT was found to induce the expression of ROS and p-JNK. ROS scavenger, N-acetyl-L-cysteine (NAC, 5 mM), was able to hinder the autophagy, apoptosis and phosphorylation of JNK, and JNK inhibitor (SP600125, 10 µM) significantly inhibited the autophagy and apoptosis, and attenuated the sensitivity of MG63 cells to AE-PDT. In conclusion, AE-PDT induced the autophagy and apoptosis of human osteosarcoma cell line MG-63 through the activation of the ROS-JNK signaling pathway. Autophagy may play a protective role during the early stage following treatment of AE-PDT. PMID:27035222

  20. Girdin/GIV is upregulated by cyclic tension, propagates mechanical signal transduction, and is required for the cellular proliferation and migration of MG-63 cells

    SciTech Connect

    Hu, Jiang-Tian; Li, Yan; Yu, Bing; Gao, Guo-Jie; Zhou, Ting; Li, Song

    2015-08-21

    To explore how Girdin/GIV is regulated by cyclic tension and propagates downstream signals to affect cell proliferation and migration. Human osteoblast-like MG-63 cells were exposed to cyclic tension force at 4000 μstrain and 0.5 Hz for 6 h, produced by a four-point bending system. Cyclic tension force upregulated Girdin and Akt expression and phosphorylation in cultured MG-63 cells. Girdin and Akt each promoted the phosphorylation of the other under stimulated tension. In vitro MTT and transwell assays showed that Girdin and Akt are required for cell proliferation and migration during cellular quiescence. Moreover, STAT3 was determined to be essential for Girdin expression under stimulated tension force in the physiological condition, as well as for osteoblast proliferation and migration during quiescence. These findings suggest that the STAT3/Girdin/Akt pathway activates in osteoblasts in response to mechanical stimulation and may play a significant role in triggering osteoblast proliferation and migration during orthodontic treatment. - Highlights: • Tension force upregulates Girdin and Akt expression and phosphorylation. • Girdin and Akt promotes the phosphorylation of each other under tension stimulation. • Girdin and Akt are required for MG-63 cell proliferation and migration. • STAT3 is essential for Girdin expression after application of the tension forces.

  1. Silencing of Ether à go-go 1 by shRNA inhibits osteosarcoma growth and cell cycle progression.

    PubMed

    Wu, Jin; Zhong, Daixing; Fu, Xijin; Liu, Qingjun; Kang, Liangqi; Ding, Zhenqi

    2014-01-01

    Recently, a member of the voltage-dependent potassium channel (Kv) family, the Ether à go-go 1 (Eag1) channel was found to be necessary for cell proliferation, cycle progression and tumorigenesis. However, the therapeutic potential of the Eag1 channel in osteosarcoma remains elusive. In the present study, a recombinant adenovirus harboring shRNA against Eag1 was constructed to silence Eag1 expression in human osteosarcoma MG-63 cells. We observed that Eag1-shRNA inhibited the proliferation and colony formation of MG-63 cells due to the induction of G1 phase arrest. Moreover, in vivo experiments showed that Eag1-shRNA inhibited osteosarcoma growth in a xenograft nude mice model. In addition, selective inhibition of Eag1 significantly decreased the expression levels of cyclin D1 and E. Taken together, our data suggest that the Eag1 channel plays a crucial role in regulating the proliferation and cell cycle of osteosarcoma cells, and represents a new and effective therapeutic target for osteosarcoma. PMID:24694542

  2. Silencing of Ether à Go-Go 1 by shRNA Inhibits Osteosarcoma Growth and Cell Cycle Progression

    PubMed Central

    Wu, Jin; Zhong, Daixing; Fu, Xijin; Liu, Qingjun; Kang, Liangqi; Ding, Zhenqi

    2014-01-01

    Recently, a member of the voltage-dependent potassium channel (Kv) family, the Ether à go-go 1 (Eag1) channel was found to be necessary for cell proliferation, cycle progression and tumorigenesis. However, the therapeutic potential of the Eag1 channel in osteosarcoma remains elusive. In the present study, a recombinant adenovirus harboring shRNA against Eag1 was constructed to silence Eag1 expression in human osteosarcoma MG-63 cells. We observed that Eag1-shRNA inhibited the proliferation and colony formation of MG-63 cells due to the induction of G1 phase arrest. Moreover, in vivo experiments showed that Eag1-shRNA inhibited osteosarcoma growth in a xenograft nude mice model. In addition, selective inhibition of Eag1 significantly decreased the expression levels of cyclin D1 and E. Taken together, our data suggest that the Eag1 channel plays a crucial role in regulating the proliferation and cell cycle of osteosarcoma cells, and represents a new and effective therapeutic target for osteosarcoma. PMID:24694542

  3. Expression and regulatory effects of microRNA-182 in osteosarcoma cells: A pilot study

    PubMed Central

    BIAN, DONG-LIN; WANG, XUE-MEI; HUANG, KUN; ZHAI, QI-XI; YU, GUI-BO; WU, CHENG-HUA

    2016-01-01

    The aim of the present study was to evaluate the expression level of microRNA-182 (miRNA-182) in human osteosarcoma (OS) MG-63 cells and OS tissues, and to elucidate the effect of miRNA-182 on the biological activity of tumors. In the present study, the expression of miRNA-182 in human OS MG-63 cells, OS tissues and normal osteoblast hFOB1.19 cells was determined using quantitative polymerase chain reaction. Subsequently, a miRNA-182 mimic and inhibitor were utilized to regulate the expression level of this miRNA in MG-63 cells. Cell viability and proliferation were examined using cell counting kit-8 assays, and cell apoptosis was detected by flow cytometry. Cell invasion and migration assays were performed using Transwell chambers to analyze the biological functions of miRNA-182 in vitro. The present study demonstrated that the expression level of miRNA-182 in MG-63 cells and OS tissues was significantly increased compared with the hFOB1.19 cell line (P<0.05). The present study successfully performed cell transfections of miRNA-182 inhibitor and miRNA-182 mimic into MG-63 cells and achieved the desired transfection efficiency. The present study confirmed that upregulation of miRNA-182 promotes cell apoptosis and inhibits cell viability, proliferation, invasion and migration. The present findings additionally demonstrated that miRNA-182 is a tumor suppressor gene in OS. Therefore, regulating the expression of miRNA-182 may affect the biological behavior of OS cells, which suggests a potential role for miRNA-182 in molecular therapy for malignant tumors. PMID:27123060

  4. hTERT promoter activity identifies osteosarcoma cells with increased EMT characteristics

    PubMed Central

    YU, LING; LIU, SHIQING; GUO, WEICHUN; ZHANG, CHUN; ZHANG, BO; YAN, HUICHAO; WU, ZHENG

    2014-01-01

    Epithelial-mesenchymal transition (EMT) is a critical step in order for epithelial-derived malignancies to metastasize, however, its role in mesenchymal-derived tumors, i.e., osteosarcoma, remains unclear. Cancer stem cells (CSCs) are enriched with cells that undergo EMT. The activity of telomerase is maintained in normal stem cells and a number of malignant tumors. The current study observed the heterogeneity of telomerase activity among individual osteosarcoma cells. We hypothesized that telomerase-positive (TELpos) cells are enriched for stem cell-like and EMT properties. A human telomerase reverse transcriptase (hTERT) promoter-reporter was applied to assess the telomerase activity of individual MG63 osteosarcoma cells and sort them into TELpos and telomerase-negative (TELneg) subpopulations. It was found that the TELpos cells exhibited an enhanced ability to form sarcospheres in vitro. In addition, TELpos cells exhibited a higher expression of vimentin, accompanied by an increased long/short axis ratio. A panel of EMT-related genes was evaluated by quantitative PCR and western blot analysis, and were found to be significantly upregulated in TELpos cells. Next, the in vitro migration capacity was examined by Transwell assay, which confirmed that TELpos cells are more prone to migration (2.6 fold). The results of the present study support the concept that EMT also applies to mesenchymal-derived osteosarcoma and draws a connection between telomerase and EMT characteristics. PMID:24348856

  5. P53 is required for Doxorubicin-induced apoptosis via the TGF-beta signaling pathway in osteosarcoma-derived cells.

    PubMed

    Sun, Yifu; Xia, Peng; Zhang, Haipeng; Liu, Biao; Shi, Ying

    2016-01-01

    Osteosarcoma is the most common type of aggressive bone cancer. Current treatment strategies include surgical resection, radiation, and chemotherapy. Doxorubicin has been widely used as a chemotherapeutic drug to treat osteosarcoma. However, drug resistance has become a challenge to its use. In this study, p53-wild type U2OS and p53-null MG-63 osteosarcoma-derived cells were used to investigate the mechanism of doxorubicin-induced cytotoxicity. In cell viability assays, doxorubicin effectively induced apoptosis in U2OS cells via the p53 signaling pathway, evidenced by elevated PUMA and p21 protein levels and activated caspase 3 cleavage. In contrast, p53-null MG-63 cells were resistant to doxorubicin-induced apoptosis, while exogenous expression of p53 increased drug sensitivity in those cells. The role of TGF-β/Smad3 signaling was investigated by using TGF-β reporter luciferase assays. Doxorubicin was able to induce TGF-β signal transduction without increasing TGF-β production in the presence of p53. Knockdown of Smad3 expression by small hairpin RNA (shRNA) showed that Smad3 was required for p53-mediated TGF-β signaling in response to doxorubicin treatment in U2OS and MG-63 cells. Taken together, these data demonstrate that p53 and TGF-β/Smad3 signaling pathways are both essential for doxorubicin-induced cytotoxicity in osteosarcoma cells. PMID:27073729

  6. Wnt5a promotes migration of human osteosarcoma cells by triggering a phosphatidylinositol-3 kinase/Akt signals

    PubMed Central

    2014-01-01

    Wnt5a is classified as a non-transforming Wnt family member and plays complicated roles in oncogenesis and cancer metastasis. However, Wnt5a signaling in osteosarcoma progression remains poorly defined. In this study, we found that Wnt5a stimulated the migration of human osteosarcoma cells (MG-63), with the maximal effect at 100 ng/ml, via enhancing phosphorylation of phosphatidylinositol-3 kinase (PI3K)/Akt. PI3K and Akt showed visible signs of basal phosphorylation and elevated phosphorylation at 15 min after stimulation with Wnt5a. Pharmaceutical inhibition of PI3K with LY294002 significantly blocked the Wnt5a-induced activation of Akt (p-Ser473) and decreased Wnt5a-induced cell migration. Akt siRNA remarkably inhibited Wnt5a-induced cell migration. Additionally, Wnt5a does not alter the total expression and phosphorylation of β-catenin in MG-63 cells. Taken together, we demonstrated for the first time that Wnt5a promoted osteosarcoma cell migration via the PI3K/Akt signaling pathway. These findings could provide a rationale for designing new therapy targeting osteosarcoma metastasis. PMID:24524196

  7. Mechanosensitivity of human osteosarcoma cells and phospholipase C {beta}2 expression

    SciTech Connect

    Hoberg, M. . E-mail: Maik.Hoberg@med.uni-tuebingen.de; Gratz, H.-H.; Noll, M.; Jones, D.B.

    2005-07-22

    Bone adapts to mechanical load by osteosynthesis, suggesting that osteoblasts might respond to mechanical stimuli. We therefore investigated cell proliferation and phospholipase C (PLC) expression in osteoblasts. One Hertz uniaxial stretching at 4000 {mu}strains significantly increased the proliferation rates of human osteoblast-like osteosarcoma cell line MG-63 and primary human osteoblasts. However, U-2/OS, SaOS-2, OST, and MNNG/HOS cells showed no significant changes in proliferation rate. We investigated the expression pattern of different isoforms of PLC in these cell lines. We were able to detect PLC {beta}1, {beta}3, {gamma}1, {gamma}2, and {delta}1 in all cells, but PLC {beta}2 was only detectable in the mechanosensitive cells. We therefore investigated the possible role of PLC {beta}2 in mechanotransduction. Inducible antisense expression for 24 h inhibited the translation of PLC {beta}1 in U-2/OS cells by 35% and PLC {beta}2 in MG-63 by 29%. Fluid shear flow experiments with MG-63 lacking PLC {beta}2 revealed a significantly higher level of cells losing attachment to coverslips and a significantly lower number of cells increasing intracellular free calcium.

  8. MiR-193a-3p and miR-193a-5p suppress the metastasis of human osteosarcoma cells by down-regulating Rab27B and SRR, respectively.

    PubMed

    Pu, Youguang; Zhao, Fangfang; Cai, Wenjing; Meng, Xianghui; Li, Yinpeng; Cai, Shanbao

    2016-04-01

    MicroRNAs have been identified as key players in the development and progression of osteosarcoma, which is the most common primary malignancy of bone. Sequencing-based miR-omic and quantitative real-time PCR analyses suggested that the expression of miR-193a-3p and miR-193a-5p was decreased by DNA methylation at their promoter region in a highly metastatic osteosarcoma cell line (MG63.2) relative to their expression in the less metastatic MG63 cell line. Further wound-healing and invasion assays demonstrated that both miR-193a-3p and miR-193a-5p suppressed osteosarcoma cell migration and invasion. Moreover, introducing miR-193a-3p and miR-193a-5p mimics into MG63.2 cells or antagomiRs into MG63 cells confirmed their critical roles in osteosarcoma metastasis. Additionally, bioinformatics prediction along with biochemical assay results clearly suggested that the secretory small GTPase Rab27B and serine racemase (SRR) were direct targets of miR-193a-3p and miR-193a-5p, respectively. These two targets are indeed involved in the miR-193a-3p- and miR-193a-5p-induced suppression of osteosarcoma cell migration and invasion. MiR-193a-3p and miR-193a-5p play important roles in osteosarcoma metastasis through down-regulation of the Rab27B and SRR genes and therefore may serve as useful biomarkers for the diagnosis of osteosarcoma and as potential candidates for the treatment of metastatic osteosarcoma. PMID:26913720

  9. Si(3)N(4)-bioglass composites stimulate the proliferation of MG63 osteoblast-like cells and support the osteogenic differentiation of human bone marrow cells.

    PubMed

    Amaral, M; Costa, M A; Lopes, M A; Silva, R F; Santos, J D; Fernandes, M H

    2002-12-01

    The in vitro osteocompatibility of a novel Si(3)N(4)-bioglass composite (70-30% weight proportion) with improved mechanical properties (fracture toughness = 4.4 M Pa m(1/2); bending strength = 383 +/- 47 MPa) is reported. Immersion of the composite samples in culture medium (30 min to 7 days) resulted in rapid protein adsorption to the surface and, also, dissolution of the intergranular phase of bioglass (time-dependent process) with the formation of different size cavities. "As-received" and pre-treated material samples presented a similar behaviour concerning the proliferation of MG63 osteoblast-like cells, evaluated during a 5-day culture period. Seeded materials showed a higher cell growth rate as compared to cultures performed on the standard plastic culture plates. To assess the osteogenic potential of the composite, "as-received" material samples were seeded with human bone marrow cells and cultured for 35 days in experimental conditions that favour the development of the osteoblastic phenotype. The cell adhesion process was similar to that observed in control cultures. Cells successfully adapted to the irregularities of the surface and were able to grow towards inside the cavities; in addition, osteogenic differentiation occurred with the formation of abundant cell-mediated mineralised deposits. Results suggest that this Si(3)N(4)-bioglass composite seems to be a promising candidate for high-stress medical applications. PMID:12361631

  10. Response of MG63 osteoblast-like cells to ordered nanotopographies fabricated using colloidal self-assembly and glancing angle deposition.

    PubMed

    Wang, Peng-Yuan; Bennetsen, Dines T; Foss, Morten; Thissen, Helmut; Kingshott, Peter

    2015-01-01

    Ordered surface nanostructures have attracted much attention in different fields including biomedical engineering because of their potential to study the size effect on cellular response and modulation of cell fate. However, the ability to fabricate large-area ordered nanostructures is typically limited due to high costs and low speed of fabrication. Herein, highly ordered nanostructures with large surface areas (>1.5 × 1.5 cm(2)) were fabricated using a combination of facile techniques including colloidal self-assembly, colloidal lithography, and glancing angle deposition (GLAD). An ordered tantalum (Ta) pattern with 60-nm-height was generated using colloidal lithography. A monolayer of colloidal crystal, i.e., hexagonal close packed 720 nm polystyrene particles, was self-assembled and used as a mask. Ta patterns were subsequently generated by evaporation of Ta through the mask. The feature size was further increased by 100 or 200 nm using GLAD, resulting in the fabrication of four different surfaces (FLAT, Ta60, GLAD100, and GLAD200). Cell adhesion, proliferation, and mineralization of MG63 osteoblast-like cells were investigated on these ordered nanostructures over a 1 week period. Our results showed that cell adhesion, spreading, focal adhesion formation, and filopodia formation of the MG63 osteoblast-like cells were inhibited on the GLAD surfaces, especially the initial (24 h) attachment, resulting in a lower cell density on the GLAD surfaces. After 1 week culture, alkaline phosphatase activity and the amount of Ca was higher on the GLAD surfaces compared with Ta60 and FLAT controls, suggesting that the GLAD surfaces facilitate differentiation of osteoblasts. This study demonstrates that ordered Ta nanotopographies synthesized by combining colloidal lithography with GLAD can improve the mineralization of osteoblast-like cells providing a new platform for biomaterials and bone tissue engineering. PMID:26459103

  11. EMMPRIN, SP1 and microRNA-27a mediate physcion 8-O-β-glucopyranoside-induced apoptosis in osteosarcoma cells

    PubMed Central

    Wang, Zhaohong; Yang, Huilin

    2016-01-01

    Physcion 8-O-β-glucopyranoside (PG), the main active ingredient of Rumex japonicus, induces apoptosis and causes cell cycle arrest in human lung cancer cells. However, its anti-tumor effects are not fully understood. In this study, we explored the mechanisms underlying PG induced apoptosis in the osteosarcoma cell line MG-63. Our results showed that PG exerted anti-proliferative effects and induced apoptosis in MG-63 cells via the intrinsic mitochondrial pathway, accompanied by loss of mitochondrial membrane potential (MMP) and cytochrome C release from the mitochondria. In addition, physcion treatment significantly inhibited extracellular matrix metalloproteinase inducer (EMMPRIN) expression in MG-63 cells, in a dose-dependent manner; meanwhile, EMMPRIN protein overexpression markedly reduced PG-induced apoptosis. Moreover, our findings suggested that the modulatory effects of PG on EMMPRIN were due, at least in part, to regulation of an ROS-miR-27a/ZBTB10-Sp1 transcription factor pathway. PMID:27429847

  12. EMMPRIN, SP1 and microRNA-27a mediate physcion 8-O-β-glucopyranoside-induced apoptosis in osteosarcoma cells.

    PubMed

    Wang, Zhaohong; Yang, Huilin

    2016-01-01

    Physcion 8-O-β-glucopyranoside (PG), the main active ingredient of Rumex japonicus, induces apoptosis and causes cell cycle arrest in human lung cancer cells. However, its anti-tumor effects are not fully understood. In this study, we explored the mechanisms underlying PG induced apoptosis in the osteosarcoma cell line MG-63. Our results showed that PG exerted anti-proliferative effects and induced apoptosis in MG-63 cells via the intrinsic mitochondrial pathway, accompanied by loss of mitochondrial membrane potential (MMP) and cytochrome C release from the mitochondria. In addition, physcion treatment significantly inhibited extracellular matrix metalloproteinase inducer (EMMPRIN) expression in MG-63 cells, in a dose-dependent manner; meanwhile, EMMPRIN protein overexpression markedly reduced PG-induced apoptosis. Moreover, our findings suggested that the modulatory effects of PG on EMMPRIN were due, at least in part, to regulation of an ROS-miR-27a/ZBTB10-Sp1 transcription factor pathway. PMID:27429847

  13. Imatinib Mesylate Exerts Anti-Proliferative Effects on Osteosarcoma Cells and Inhibits the Tumour Growth in Immunocompetent Murine Models

    PubMed Central

    Ory, Benjamin; Charrier, Céline; Brion, Régis; Blanchard, Frederic; Redini, Françoise; Heymann, Dominique

    2014-01-01

    Osteosarcoma is the most common primary malignant bone tumour characterized by osteoid production and/or osteolytic lesions of bone. A lack of response to chemotherapeutic treatments shows the importance of exploring new therapeutic methods. Imatinib mesylate (Gleevec, Novartis Pharma), a tyrosine kinase inhibitor, was originally developed for the treatment of chronic myeloid leukemia. Several studies revealed that imatinib mesylate inhibits osteoclast differentiation through the M-CSFR pathway and activates osteoblast differentiation through PDGFR pathway, two key cells involved in the vicious cycle controlling the tumour development. The present study investigated the in vitro effects of imatinib mesylate on the proliferation, apoptosis, cell cycle, and migration ability of five osteosarcoma cell lines (human: MG-63, HOS; rat: OSRGA; mice: MOS-J, POS-1). Imatinib mesylate was also assessed as a curative and preventive treatment in two syngenic osteosarcoma models: MOS-J (mixed osteoblastic/osteolytic osteosarcoma) and POS-1 (undifferentiated osteosarcoma). Imatinib mesylate exhibited a dose-dependent anti-proliferative effect in all cell lines studied. The drug induced a G0/G1 cell cycle arrest in most cell lines, except for POS-1 and HOS cells that were blocked in the S phase. In addition, imatinib mesylate induced cell death and strongly inhibited osteosarcoma cell migration. In the MOS-J osteosarcoma model, oral administration of imatinib mesylate significantly inhibited the tumour development in both preventive and curative approaches. A phospho-receptor tyrosine kinase array kit revealed that PDGFRα, among 7 other receptors (PDFGFRβ, Axl, RYK, EGFR, EphA2 and 10, IGF1R), appears as one of the main molecular targets for imatinib mesylate. In the light of the present study and the literature, it would be particularly interesting to revisit therapeutic evaluation of imatinib mesylate in osteosarcoma according to the tyrosine-kinase receptor status of patients

  14. Perspectives on cancer stem cells in osteosarcoma.

    PubMed

    Basu-Roy, Upal; Basilico, Claudio; Mansukhani, Alka

    2013-09-10

    Osteosarcoma is an aggressive pediatric tumor of growing bones that, despite surgery and chemotherapy, is prone to relapse. These mesenchymal tumors are derived from progenitor cells in the osteoblast lineage that have accumulated mutations to escape cell cycle checkpoints leading to excessive proliferation and defects in their ability to differentiate appropriately into mature bone-forming osteoblasts. Like other malignant tumors, osteosarcoma is often heterogeneous, consisting of phenotypically distinct cells with features of different stages of differentiation. The cancer stem cell hypothesis posits that tumors are maintained by stem cells and it is the incomplete eradication of a refractory population of tumor-initiating stem cells that accounts for drug resistance and tumor relapse. In this review we present our current knowledge about the biology of osteosarcoma stem cells from mouse and human tumors, highlighting new insights and unresolved issues in the identification of this elusive population. We focus on factors and pathways that are implicated in maintaining such cells, and differences from paradigms of epithelial cancers. Targeting of the cancer stem cells in osteosarcoma is a promising avenue to explore to develop new therapies for this devastating childhood cancer. PMID:22659734

  15. Influence of USP laser radiation on cell morphology: HaCat and MG-63 cell lines for bone and soft tissue modelling in dentistry

    NASA Astrophysics Data System (ADS)

    Meister, Joerg; Schelle, Florian; Beier, Imke; Bourauel, Christoph; Frentzen, Matthias; Kraus, Dominik

    Due to the high intensities of USP laser radiation, the interaction with matter is always attended with a plasma formation. Therefore the surrounding tissue can be influenced by heat generation and additional light emission from the UV up to the near and mid infrared. In dentistry it is of importance that the treatment of bone and soft tissues, i.e. oral mucosa, with a USP laser should not cause any kind of morphological changes on the cell level leading to a delayed wound healing or cell mutation. HaCaT keratinocyte cells were used for epidermal (soft tissue) and MG-63 osteoblast-like cells for hard tissue (bone) modelling. Cell growing was realized on glas cover slips. Irradiation was carried out with a USP Nd:YVO4 laser having a center wavelength at 1064 nm. Based on the pulse duration of 8 ps and a pulse repetition rate of 500 kHz the laser emits an average power of 9 W. For efficiency testing of cell removal on glas cover slips, 1, 5, 25, 50 and 75 repetitions of the scanning pattern (scan loops) were used. Heat distribution during laser irradiation was measured with an infrared camera system. Subsequently haematoxylin staining and SEM investigations were used to analyse the morphological changes. Differences of cell removal efficiency were observed with repetitions <=25. Irradiated areas with repetitions >=50 were cell-free. Additionally, repetitions >=25 showed side effects for both cell lines. Cell destruction in both cell lines could be verified using the haematoxylin staining and the SEM pictures.

  16. Effects of Watercress Containing Rutin and Rutin Alone on the Proliferation and Osteogenic Differentiation of Human Osteoblast-like MG-63 Cells

    PubMed Central

    Hyun, Hanbit; Park, Heajin; Jeong, Jaehoon; Kim, Jihye; Kim, Haesung; Oh, Hyun Il; Hwang, Hye Seong

    2014-01-01

    Most known osteoporosis medicines are effective for bone resorption, and so there is an increasing demand for medicines that stimulate bone formation. Watercress (N. officinale R. Br.) is widely used as a salad green and herbal remedy. This study analyzed a watercress extract using ultra-performance liquid chromatography/mass spectrometry, and identified a rutin as one of its major constituents. Osteogenic-related assays were used to compare the effects of watercress containing rutin (WCR) and rutin alone on the proliferation and differentiation of human osteoblast-like MG-63 cells. The reported data are expressed as percentages relative to the control value (medium alone; assigned as 100%). WCR increased cell proliferation to 125.0±4.0% (mean±SD), as assessed using a cell viability assay, and increased the activity of alkaline phosphatase, an early differentiation marker, to 222.3±33.8%. In addition, WCR increased the expression of collagen type I, another early differentiation marker, to 149.2±2.8%, and increased the degree of mineralization, a marker of the late process of differentiation, to 122.9±3.9%. Rutin alone also increased the activity of ALP (to 154.4±12.2%), the expression of collagen type I (to 126.6±6.2%), and the degree of mineralization (to 112.3±5.0%). Daidzein, which is reported to stimulate bone formation, was used as a positive control; the effects of WCR on proliferation and differentiation were significantly greater than those of daidzein. These results indicate that WCR and rutin can both induce bone formation via the differentiation of MG-63 cells. This is the first study demonstrating the effectiveness of either WCR or rutin as an osteoblast stimulant. PMID:25177168

  17. Effects of Watercress Containing Rutin and Rutin Alone on the Proliferation and Osteogenic Differentiation of Human Osteoblast-like MG-63 Cells.

    PubMed

    Hyun, Hanbit; Park, Heajin; Jeong, Jaehoon; Kim, Jihye; Kim, Haesung; Oh, Hyun Il; Hwang, Hye Seong; Kim, Ha Hyung

    2014-08-01

    Most known osteoporosis medicines are effective for bone resorption, and so there is an increasing demand for medicines that stimulate bone formation. Watercress (N. officinale R. Br.) is widely used as a salad green and herbal remedy. This study analyzed a watercress extract using ultra-performance liquid chromatography/mass spectrometry, and identified a rutin as one of its major constituents. Osteogenic-related assays were used to compare the effects of watercress containing rutin (WCR) and rutin alone on the proliferation and differentiation of human osteoblast-like MG-63 cells. The reported data are expressed as percentages relative to the control value (medium alone; assigned as 100%). WCR increased cell proliferation to 125.0±4.0% (mean±SD), as assessed using a cell viability assay, and increased the activity of alkaline phosphatase, an early differentiation marker, to 222.3±33.8%. In addition, WCR increased the expression of collagen type I, another early differentiation marker, to 149.2±2.8%, and increased the degree of mineralization, a marker of the late process of differentiation, to 122.9±3.9%. Rutin alone also increased the activity of ALP (to 154.4±12.2%), the expression of collagen type I (to 126.6±6.2%), and the degree of mineralization (to 112.3±5.0%). Daidzein, which is reported to stimulate bone formation, was used as a positive control; the effects of WCR on proliferation and differentiation were significantly greater than those of daidzein. These results indicate that WCR and rutin can both induce bone formation via the differentiation of MG-63 cells. This is the first study demonstrating the effectiveness of either WCR or rutin as an osteoblast stimulant. PMID:25177168

  18. Polydatin promotes apoptosis through upregulation the ratio of Bax/Bcl-2 and inhibits proliferation by attenuating the β-catenin signaling in human osteosarcoma cells

    PubMed Central

    Xu, Ge; Kuang, Ge; Jiang, Wengao; Jiang, Rong; Jiang, Dianming

    2016-01-01

    Osteosarcoma is the most prevalent primary malignant bone tumor mainly endangering young adults. In this study, we explore whether polydatin (PD), a glycoside form of resveratrol, is effective for osteosarcoma. Our results showed that PD dose-dependently inhibited proliferation and promoted apoptosis in 143B and MG63 osteosarcoma cells, examined by MTT assay and Annexin V-FITC apoptosis detection. Further, we found PD increased expression of Bax and attenuated expression of Bcl-2, and consequently augmented caspase-3 activity. Moreover, PD also dose-dependently inhibited β-catenin signaling pathway as indicated by decreased β-catenin expression and activity, while overexpression of β-catenin by adenoviruses system could abrogate the anti-tumor effect of PD. Our finding indicated that PD could inhibit the proliferation by inhibiting the β-catenin signaling and induce apoptosis via upregulation the ratio of Bax/Bcl-2 in human osteosarcoma cells. PMID:27158379

  19. Signal transduction and downregulation of C-MET in HGF stimulated low and highly metastatic human osteosarcoma cells

    SciTech Connect

    Husmann, Knut; Ducommun, Pascal; Sabile, Adam A.; Pedersen, Else-Marie; Born, Walter; Fuchs, Bruno

    2015-09-04

    The poor outcome of osteosarcoma (OS), particularly in patients with metastatic disease and a five-year survival rate of only 20%, asks for more effective therapeutic strategies targeting malignancy-promoting mechanisms. Dysregulation of C-MET, its ligand hepatocyte growth factor (HGF) and the fusion oncogene product TPR-MET, first identified in human MNNG-HOS OS cells, have been described as cancer-causing factors in human cancers. Here, the expression of these molecules at the mRNA and the protein level and of HGF-stimulated signaling and downregulation of C-MET was compared in the parental low metastatic HOS and MG63 cell lines and the respective highly metastatic MNNG-HOS and 143B and the MG63-M6 and MG63-M8 sublines. Interestingly, expression of TPR-MET was only observed in MNNG-HOS cells. HGF stimulated the phosphorylation of Akt and Erk1/2 in all cell lines investigated, but phospho-Stat3 remained at basal levels. Downregulation of HGF-stimulated Akt and Erk1/2 phosphorylation was much faster in the HGF expressing MG63-M8 cells than in HOS cells. Degradation of HGF-activated C-MET occurred predominantly through the proteasomal and to a lesser extent the lysosomal pathway in the cell lines investigated. Thus, HGF-stimulated Akt and Erk1/2 signaling as well as proteasomal degradation of HGF activated C-MET are potential therapeutic targets in OS. - Highlights: • Expression of TPR-MET was only observed in MNNG-HOS cells. • HGF stimulated the phosphorylation of Akt and Erk1/2 but not of Stat3 in osteosarcoma cell lines. • Degradation of HGF-activated C-MET occurred predominantly through the proteasomal pathway.

  20. Interaction of Human Osteoblast-Like Saos-2 and MG-63 Cells with Thermally Oxidized Surfaces of a Titanium-Niobium Alloy

    PubMed Central

    Vandrovcova, Marta; Jirka, Ivan; Novotna, Katarina; Lisa, Vera; Frank, Otakar; Kolska, Zdenka; Stary, Vladimir; Bacakova, Lucie

    2014-01-01

    An investigation was made of the adhesion, growth and differentiation of osteoblast-like MG-63 and Saos-2 cells on titanium (Ti) and niobium (Nb) supports and on TiNb alloy with surfaces oxidized at 165°C under hydrothermal conditions and at 600°C in a stream of air. The oxidation mode and the chemical composition of the samples tuned the morphology, topography and distribution of the charge on their surfaces, which enabled us to evaluate the importance of these material characteristics in the interaction of the cells with the sample surface. Numbers of adhered MG-63 and Saos-2 cells correlated with the number of positively-charged (related with the Nb2O5 phase) and negatively-charged sites (related with the TiO2 phase) on the alloy surface. Proliferation of these cells is correlated with the presence of positively-charged (i.e. basic) sites of the Nb2O5 alloy phase, while cell differentiation is correlated with negatively-charged (acidic) sites of the TiO2 alloy phase. The number of charged sites and adhered cells was substantially higher on the alloy sample oxidized at 600°C than on the hydrothermally treated sample at 165°C. The expression values of osteoblast differentiation markers (collagen type I and osteocalcin) were higher for cells grown on the Ti samples than for those grown on the TiNb samples. This was more particularly apparent in the samples treated at 165°C. No considerable immune activation of murine macrophage-like RAW 264.7 cells on the tested samples was found. The secretion of TNF-α by these cells into the cell culture media was much lower than for either cells grown in the presence of bacterial lipopolysaccharide, or untreated control samples. Thus, oxidized Ti and TiNb are both promising materials for bone implantation; TiNb for applications where bone cell proliferation is desirable, and Ti for induction of osteogenic cell differentiation. PMID:24977704

  1. Ferulic acid inhibits proliferation and promotes apoptosis via blockage of PI3K/Akt pathway in osteosarcoma cell.

    PubMed

    Wang, Ting; Gong, Xia; Jiang, Rong; Li, Hongzhong; Du, Weimin; Kuang, Ge

    2016-01-01

    Ferulic acid, a ubiquitous phenolic acid abundant in corn, wheat and flax, has potent anti-tumor effect in various cancer cell lines. However, the anti-tumor effect of ferulic acid on osteosarcoma remains unclear. Therefore, we conduct current study to examine the effect of ferulic acid on osteosarcoma cells and explore the underlying mechanisms. In present study, ferulic acid inhibited proliferation and induced apoptosis in both 143B and MG63 osteosarcoma cells dose-dependently, indicated by MTT assay and Annexin V-FITC apoptosis detection. Additionally, ferulic acid induced G0/G1 phase arrest and down-regulated the expression of cell cycle-related protein, CDK 2, CDK 4, CDK 6, confirmed by flow cytometry assay and western blotting. Moreover, ferulic acid upregulated Bax, downregulated Bcl-2, and subsequently enhanced caspase-3 activity. More importantly, ferulic acid dose-dependently inhibited PI3K/Akt activation. Using adenoviruses expressing active Akt, the anti-proliferation and pro-apoptosis of ferulic acid were reverted. Our results demonstrated that ferulic acid might inhibit proliferation and induce apoptosis via inhibiting PI3K/Akt pathway in osteosarcoma cells. Ferulic acid is a novel therapeutic agent for osteosarcoma. PMID:27158383

  2. Ferulic acid inhibits proliferation and promotes apoptosis via blockage of PI3K/Akt pathway in osteosarcoma cell

    PubMed Central

    Wang, Ting; Gong, Xia; Jiang, Rong; Li, Hongzhong; Du, Weimin; Kuang, Ge

    2016-01-01

    Ferulic acid, a ubiquitous phenolic acid abundant in corn, wheat and flax, has potent anti-tumor effect in various cancer cell lines. However, the anti-tumor effect of ferulic acid on osteosarcoma remains unclear. Therefore, we conduct current study to examine the effect of ferulic acid on osteosarcoma cells and explore the underlying mechanisms. In present study, ferulic acid inhibited proliferation and induced apoptosis in both 143B and MG63 osteosarcoma cells dose-dependently, indicated by MTT assay and Annexin V-FITC apoptosis detection. Additionally, ferulic acid induced G0/G1 phase arrest and down-regulated the expression of cell cycle-related protein, CDK 2, CDK 4, CDK 6, confirmed by flow cytometry assay and western blotting. Moreover, ferulic acid upregulated Bax, downregulated Bcl-2, and subsequently enhanced caspase-3 activity. More importantly, ferulic acid dose-dependently inhibited PI3K/Akt activation. Using adenoviruses expressing active Akt, the anti-proliferation and pro-apoptosis of ferulic acid were reverted. Our results demonstrated that ferulic acid might inhibit proliferation and induce apoptosis via inhibiting PI3K/Akt pathway in osteosarcoma cells. Ferulic acid is a novel therapeutic agent for osteosarcoma. PMID:27158383

  3. Genetic and molecular characterization of the human osteosarcoma 3AB-OS cancer stem cell line: a possible model for studying osteosarcoma origin and stemness.

    PubMed

    Di Fiore, Riccardo; Fanale, Daniele; Drago-Ferrante, Rosa; Chiaradonna, Ferdinando; Giuliano, Michela; De Blasio, Anna; Amodeo, Valeria; Corsini, Lidia R; Bazan, Viviana; Tesoriere, Giovanni; Vento, Renza; Russo, Antonio

    2013-06-01

    Finding new treatments targeting cancer stem cells (CSCs) within a tumor seems to be critical to halt cancer and improve patient survival. Osteosarcoma is an aggressive tumor affecting adolescents, for which there is no second-line chemotherapy. Uncovering new molecular mechanisms underlying the development of osteosarcoma and origin of CSCs is crucial to identify new possible therapeutic strategies. Here, we aimed to characterize genetically and molecularly the human osteosarcoma 3AB-OS CSC line, previously selected from MG63 cells and which proved to have both in vitro and in vivo features of CSCs. Classic cytogenetic studies demonstrated that 3AB-OS cells have hypertriploid karyotype with 71-82 chromosomes. By comparing 3AB-OS CSCs to the parental cells, array CGH, Affymetrix microarray, and TaqMan® Human MicroRNA array analyses identified 49 copy number variations (CNV), 3,512 dysregulated genes and 189 differentially expressed miRNAs. Some of the chromosomal abnormalities and mRNA/miRNA expression profiles appeared to be congruent with those reported in human osteosarcomas. Bioinformatic analyses selected 196 genes and 46 anticorrelated miRNAs involved in carcinogenesis and stemness. For the first time, a predictive network is also described for two miRNA family (let-7/98 and miR-29a,b,c) and their anticorrelated mRNAs (MSTN, CCND2, Lin28B, MEST, HMGA2, and GHR), which may represent new biomarkers for osteosarcoma and may pave the way for the identification of new potential therapeutic targets. PMID:23129384

  4. A novel long non-coding RNA, hypoxia-inducible factor-2α promoter upstream transcript, functions as an inhibitor of osteosarcoma stem cells in vitro

    PubMed Central

    WANG, YONGCHENG; YAO, JIE; MENG, HAOYE; YU, ZHIGUO; WANG, ZHIGANG; YUAN, XUELING; CHEN, HONG; WANG, AIYUAN

    2015-01-01

    Long non-coding RNAs (lncRNAs) have recently been identified as novel modulators of malignant tumors. However, the function of lncRNAs in cancer stem cells (CSCs) remains to be elucidated. The present study aimed to investigate the regulating role of a novel lncRNA, hypoxia-inducible factor-2α (HIF-2α) promoter upstream transcript (HIF2PUT), in osteosarcoma stem cells. The expression levels of HIF2PUT were assessed by quantitative polymerase chain reaction in 17 osteosarcoma tissue specimens, and the correlation between the expression of HIF2PUT and its host transcript-HIF-2α was determined. In functional experiments, HIF2PUT expression was knocked down by small interfering RNAs, or overexpressed by transfection with pcDNA-HIF2PUT, in order to evaluate the effects of HIF2PUT on cell proliferation, migration, expression rate of osteosarcoma stem cell marker CD133, and stem sphere-forming ability in MG63 cells. HIF2PUT expression levels were positively correlated with HIF-2α in osteosarcoma tissues. Overexpression of HIF2PUT markedly inhibited cell proliferation and migration, decreased the percentage of CD133 expressing cells, and impaired the osteosarcoma stem sphere-forming ability of the MG63 cells. Whereas, knockdown of HIF2PUT expression had the opposite effect. Furthermore, altering the expression of HIF2PUT resulted in a concomitant change to HIF-2α mRNA expression. These results indicate that the lncRNA HIF2PUT may be a novel regulatory factor of osteosarcoma stem cells, which may exert its function partly by controlling HIF-2α expression. Further studies regarding HIF2PUT may provide a novel therapeutic target of osteosarcoma in the future. PMID:25434862

  5. Effect of various concentrations of Ti in hydrocarbon plasma polymer films on the adhesion, proliferation and differentiation of human osteoblast-like MG-63 cells

    NASA Astrophysics Data System (ADS)

    Vandrovcova, Marta; Grinevich, Andrey; Drabik, Martin; Kylian, Ondrej; Hanus, Jan; Stankova, Lubica; Lisa, Vera; Choukourov, Andrei; Slavinska, Danka; Biederman, Hynek; Bacakova, Lucie

    2015-12-01

    Hydrocarbon polymer films (ppCH) enriched with various concentrations of titanium were deposited on microscopic glass slides by magnetron sputtering from a Ti target. The maximum concentration of Ti (about 20 at.%) was achieved in a pure argon atmosphere. The concentration of Ti decreased rapidly after n-hexane vapors were introduced into the plasma discharge, and reached zero values at n-hexane flow of 0.66 sccm. The decrease in Ti concentration was associated with decreasing oxygen and titanium carbide concentration in the films, decreasing wettability (the water drop contact angle increased from 20° to 91°) and decreasing root-mean-square roughness (from 3.3 nm to 1.0 nm). The human osteoblast-like MG-63 cells cultured on pure ppCH films and on films with 20 at.% of Ti showed relatively high concentrations of ICAM-1, a marker of cell immune activation. Lower concentrations of Ti (mainly 5 at.%) improved cell adhesion and osteogenic differentiation, as revealed by higher concentrations of talin, vinculin and osteocalcin. Higher Ti concentrations (15 at.%) supported cell growth, as indicated by the highest final cell population densities on day 7 after seeding. Thus, enrichment of ppCH films with appropriate concentrations of Ti makes these films more suitable for potential coatings of bone implants.

  6. In vitro characterization of MG-63 osteoblast-like cells cultured on organic-inorganic lyophilized gelatin sponges for early bone healing.

    PubMed

    Rodriguez, Isaac A; Saxena, Gunjan; Hixon, Katherine R; Sell, Scott A; Bowlin, Gary L

    2016-08-01

    The development of three-dimensional porous scaffolds with enhanced osteogenic and angiogenic potential would be beneficial for inducing early-stage bone regeneration. Previous studies have demonstrated the advantages of mineralized and nonmineralized acellular 1-Ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride (EDC) cross-linked gelatin sponges enhanced with preparations rich in growth factors, hydroxyapatite, and chitin whiskers. In this study, those same scaffolds were mineralized and dynamically seeded with MG-63 cells. Cell proliferation, protein/cytokine secretion, and compressive mechanical properties of scaffolds were evaluated. It was found that mineralization and the addition of growth factors increased cell proliferation compared to gelatin controls. Cells on all scaffolds responded in an appropriate bone regenerative fashion as shown through osteocalcin secretion and little to no secretion of bone resorbing markers. However, compressive mechanical properties of cellularized scaffolds were not significantly different from acellular scaffolds. The combined results of increased cellular attachment, infiltration, and bone regenerative protein/cytokine secretion on scaffolds support the need for the addition of a bone-like mineral surface. Cellularized scaffolds containing growth factors reported similar advantages and mechanical values in the range of native tissues present in the early stages of bone healing. These results suggest that the developed composite sponges exhibited cellular responses and mechanical properties appropriate for promoting early bone healing in various applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2011-2019, 2016. PMID:27038217

  7. Molecular mechanisms of Polyphyllin I-induced apoptosis and reversal of the epithelial-mesenchymal transition in human osteosarcoma cells.

    PubMed

    Chang, Junli; Wang, Hongshen; Wang, Xianyang; Zhao, Yongjian; Zhao, Dongfeng; Wang, Chenglong; Li, Yimian; Yang, Zhilie; Lu, Sheng; Zeng, Qinghua; Zimmerman, Jacquelyn; Shi, Qi; Wang, Yongjun; Yang, Yanping

    2015-07-21

    Osteosarcoma is a most common highly malignant bone tumor in children and adolescents. Polyphyllin I (PPI) is an ethanol extraction from Paris polyphylla Smith var.yunnanensis (Franch.) Hand.-Mazz, which belongs to antipyretic-detoxicate family and has been used as a natural medicine in the treatment of infectious disease and cancer in China for centuries. The proteasome activity inhibitory and anti-osteosarcoma effects of PPI have not been known. Here we found PPI exhibited a selective inhibitory effect on proteasomal chymotrypsin (CT)-like activity, both in purified human proteasome and in cultured osteosarcoma cellular proteasome, and caused an accumulation of ubiquitinated proteins. PPI also inhibited viability, proliferation, migration, and invasion of MG-63, Saos-2, and U-2 OS osteosarcoma cells and resulted in S phase arrest and apoptosis. Furthermore, we explored the molecular targets involved. Exposure of osteosarcoma cells to PPI caused an inactivation of the intrinsic nuclear factor κB (NF-κB) and activation of unfolded protein response (UPR)/endoplasmic reticulum (ER) stress signaling cascade in osteosarcoma cells, followed by down-regulation of anti-apoptotic proteins, with up-regulation of pro-apoptotic proteins. We also demonstrated down-regulation of c-Myc, Cyclin B1, Cyclin D1, and CDK1, which are involved in the cell cycle and growth. Finally, we identified down-regulation of Vimentin, Snail, Slug, and up-regulation of E-cadherin, which are integral proteins involved in epithelial-mesenchymal transition (EMT). Taken together, our data provide insights into the mechanism underlying the anticancer activity of PPI in human osteosarcoma cells. PMID:25978954

  8. Cytotoxic Effects and Osteogenic Activity of Calcium Sulfate with and without Recombinant Human Bone Morphogenetic Protein 2 and Nano-Hydroxyapatite Adjacent to MG-63 Cell Line

    PubMed Central

    Ghorbanzadeh, Abdollah; Aminsobhani, Mohsen; Khoshzaban, Ahad; Abbaszadeh, Armin; Ghorbanzadeh, Atiyeh; Shamshiri, Ahmad Reza

    2015-01-01

    Objectives: The aim of this study was to assess the cytotoxic effects and osteogenic activity of recombinant human bone morphogenetic protein (rhBMP2) and nano-hydroxyapatite (n-HA) adjacent to MG-63 cell line. Materials and Methods: To assess cytotoxicity, the 4,5-dimethyl thiazolyl-2,5-diphenyl tetrazolium bromide (MTT) assay was used. Alkaline phosphatase (ALP) activity and osteogenic activity were evaluated using Alizarin red and the von Kossa staining and analyzed by one-way ANOVA followed by Tukey’s post hoc test. Results: The n-HA/calcium sulfate (CS) mixture significantly promoted cell growth in comparison to pure CS. Moreover, addition of rhBMP2 to CS (P=0.02) and also mixing CS with n-HA led to further increase in extracellular calcium production and ALP activity (P=0.03). Conclusion: This in vitro study indicates that a scaffold material in combination with an osteoinductive material is effective for bone matrix formation. PMID:26877731

  9. MicroRNA-184 Modulates Doxorubicin Resistance in Osteosarcoma Cells by Targeting BCL2L1

    PubMed Central

    Lin, Bo-chuan; Huang, Dong; Yu, Chao-qun; Mou, Yong; Liu, Yuan-hang; Zhang, Da-wei; Shi, Feng-jun

    2016-01-01

    Background Early metastasis of osteosarcoma (OS) is highly lethal and responds poorly to drug and radiation therapies. MicroRNAs (miRNAs) are a class of small noncoding RNAs that modulate gene expression at the post-transcriptional level. However, the detailed functions of specific miRNAs are not entirely understood. The aim of the present study was to investigate the role of miR-184 as a mediator of drug resistance in human osteosarcoma. Material/Methods qRT-PCR was used to analyze the expression level of miR-184 in OS cell line U-2 OS and MG-63 treated with doxorubicin. MiR-184 agomir or miR-184 antagomir was transferred into cells to regulated miR-184. The target of miR-184 was predicted by TargetScan and confirmed by luciferase reporter assay. Bcl-2-like protein 1 (BCL2L1) expression was detected by Western blot. Cell apoptosis was determined by Annexin V staining and analysis by flow cytometry. Results Doxorubicin induced time-dependent expression of miR-184 in OS cell line U-2 OS and MG-63. Luciferase reporter assay identified BCL2L1 as the direct target gene of miR-184. Furthermore, doxorubicin reduced BCL2L1 expression, which was reversed by miR-184 overexpression and further decreased by miR-184 inhibition in OS cells. In addition, miR-184 agomir reduced doxorubicin-induced cell apoptosis, whereas miR-184 antagomir enhanced apoptosis in OS cells, suggesting that up-regulation of miR-184 contributes to chemoresistance of the OS cell line. Conclusions Our data show that miR-184 was up-regulated in OS patients treated with doxorubicin therapy and leads to poor response to drug therapy by targeting BCL2L1. PMID:27222034

  10. Actein Inhibits Cell Proliferation and Migration in Human Osteosarcoma

    PubMed Central

    Chen, Zhi; Wu, Jingdong; Guo, Qinghao

    2016-01-01

    Background Osteosarcoma is one of the most common malignant bone cancers worldwide. Although the traditional chemotherapies have made some progression in the past decades, the mortality of osteosarcoma in children and adolescent is very high. Herein, the role of actein in osteosarcoma was explored. Material/Methods Cell viability assay was performed in osteosarcoma cell lines 143B and U2OS. Colony formation analysis was included when cells were treated with different doses of actin. Cell cycle assay was conducted to further examine the role of actein. Cell apoptotic rate and the relative activities of caspase-3, caspase-8, and caspase-9 were detected in 143B and U2OS osteosarcoma cells. Moreover, transwell assays were used to explore the effects of actein on cell metastasis. Results Actein significantly inhibited osteosarcoma cell viability in a time- and dose-dependent manner. Actein also dramatically suppressed the colony formation ability in osteosarcoma143B and U2OS cells. It was revealed that osteosarcoma cells were arrested in G0/G1 phase in the cell cycle progression and induced to apoptosis by administration of actein. The activities of pro-apoptotic factors such as caspase-3 and caspase-9 were significantly increased by actein. Furthermore, administration of actein decreased cell migrated and invasive abilities in both 143B and U2OS cell lines. Conclusions Actein inhibits tumor growth by inducing cell apoptosis in osteosarcoma. The inhibitive roles of actein in cell proliferation, migration and invasion suggest that actein may serve as a potential therapeutic agent in the treatment of osteosarcoma. PMID:27173526

  11. RLN2 Is a Positive Regulator of AKT-2-Induced Gene Expression Required for Osteosarcoma Cells Invasion and Chemoresistance

    PubMed Central

    Ma, Jinfeng; Huang, Hai; Han, Zenggang; Zhu, Changzheng; Yue, Bin

    2015-01-01

    The aim of the study was to determine the effect of H2 relaxin (RLN2) on invasion, migration, and chemosensitivity to cisplatin in human osteosarcoma U2-OS and MG-63 cells and then to investigate the effect of RLN2 on the AKT/NF-κB signaling pathway. The expression of RLN2, p-AKT (Ser473), and p-ERK1/2 (Phospho-Thr202/Tyr204) proteins was detected by western blot in OS tissues from 21 patients with pulmonary metastatic disease, and the correlation between RLN2 and p-AKT or RLN2 and p-ERK1/2 expression was investigated. RLN2 expression was inhibited by RLN2 siRNA transfection in the MG-63 cells. RLN2 was overexpressed in the U2-OS cells by treatment with recombinant relaxin. The results showed that positive relation was found between RLN2 and p-AKT expression in tissues of OS. Silencing RLN2 inhibited cell migratory and invasive ability and angiogenesis formation and increased the chemosensitivity to cisplatin in MG-63 cells. RLN2 overexpression promoted migratory and invasive ability and angiogenesis and increased the chemoresistance to cisplatin in U2-OS cells. Silencing RLN2 inhibited the activity of AKT/NF-κB signaling pathway in MG-63 cells, and vice versa. Blockage of both pathways by specific inhibitors abrogated RLN2-induced survival and invasion of OS cells, and vice versa. Our results indicated RLN2 confers to migratory and invasive ability, angiogenesis, and chemoresistance to cisplatin via modulating the AKT/NF-κB signaling pathway in vitro. PMID:26229955

  12. Fraxetin inhibits the induction of anti-Fas IgM, tumor necrosis factor-alpha and interleukin-1beta-mediated apoptosis by Fas pathway inhibition in human osteoblastic cell line MG-63.

    PubMed

    Kuo, Po-Lin; Huang, Yu-Ting; Chang, Cheng-Hsiung; Chang, Jiunn-Kae

    2006-07-01

    The survival of osteoblast cells is one of the determinants of the development of osteoporosis in patients with inflamed synovium, such as in rheumatoid arthritis (RA). By means of alkaline phosphatase (ALP) activity and osteocalcin ELISA assay, we have shown that fraxetin exhibits a significant induction of differentiation in the human osteoblast-like cell line MG-63. In addition, we also assessed whether fraxetin affects inflammatory cytokine-mediated apoptosis in osteoblast cells. TNF-alpha or IL-1beta enhance apoptotic DNA fragmentation in anti-Fas IgM-treated MG-63 cells by increasing Fas receptor expression. However, TNF-alpha or IL-1beta treatment alone does not induce apoptosis. Treatment of MG-63 cells with fraxetin not only inhibited anti-Fas IgM-induced apoptosis, but also blocked the synergetic effect of anti-Fas IgM with TNF-alpha or IL-1beta on cell death. The apoptotic inhibition of fraxetin is associated with inhibition of TNF-alpha and IL-1beta-mediated Fas expression and enhancement of FLIP expression, resulting in a decrease of caspase-8 and caspase-3 activation. These results indicate a potential use of fraxetin in preventing osteoporosis by inhibiting inflammatory cytokine-mediated apoptosis in osteoblast cells. PMID:16714221

  13. Heterogeneous expression and biological function of ubiquitin carboxy-terminal hydrolase-L1 in osteosarcoma.

    PubMed

    Zheng, Shuier; Qiao, Guanglei; Min, Daliu; Zhang, Zhichang; Lin, Feng; Yang, Qingcheng; Feng, Tao; Tang, Lina; Sun, Yuanjue; Zhao, Hui; Li, Hongtao; Yu, Wenxi; Yang, Yumei; Shen, Zan; Yao, Yang

    2015-04-01

    Ubiquitin carboxyl terminal hydrolase 1 (UCHL1), a member of the UCH class of DUBs, has been reported as either an oncogene or a tumor suppressor. However, the molecular mechanism underlying the biological function of UCHL1 in osteosarcoma is still unclear. This study was aimed at elucidating the roles of UCHL1 in regulating the biological behavior of osteosarcoma cells. In this study, we found that UCHL1 was elevated in osteosarcoma compared with normal bone tissue. Moreover, UCHL1 expression level was correlated with tumor maximum diameter, high rate of lung metastases and short survival time. Then, we found that knockdown of UCHL1 in osteosarcoma cell MG63 inhibited cell proliferation and significantly increased cell population in the G1 phase. Several cyclins promoting G1/S phase transition were reduced after UCHL1 knockdown, including cell cycle regulator cyclin D1, cyclin E1 and CDK6. Moreover, inhibition of UCHL1 in MG63 cells dramatically induced cell apoptosis. We also found that down-regulation of UCHL1 in MG63 significantly inhibited cell invasion. Then, we found that there was a positive correlation between UCHL1 expression level and the Akt and ERK phosphorylation status. Finally, in vivo data showed that knockdown of UCHL1 inhibited osteosarcoma growth in nude mice. These results indicate that UCHL1 could work as an oncogene and may serve as a promising therapeutic strategy for osteosarcoma. PMID:25578779

  14. Involvement of PAR-4 in Cannabinoid-Dependent Sensitization of Osteosarcoma Cells to TRAIL-Induced Apoptosis

    PubMed Central

    Notaro, Antonietta; Sabella, Selenia; Pellerito, Ornella; Di Fiore, Riccardo; De Blasio, Anna; Vento, Renza; Calvaruso, Giuseppe; Giuliano, Michela

    2014-01-01

    The synthetic cannabinoid WIN 55,212-2 is a potent cannabinoid receptor agonist with anticancer potential. Experiments were performed to determine the effects of WIN on proliferation, cell cycle distribution, and programmed cell death in human osteosarcoma MG63 and Saos-2 cells. Results show that WIN induced G2/M cell cycle arrest, which was associated with the induction of the main markers of ER stress (GRP78, CHOP and TRB3). In treated cells we also observed the conversion of the cytosolic form of the autophagosome marker LC3-I into LC3-II (the lipidated form located on the autophagosome membrane) and the enhanced incorporation of monodansylcadaverine and acridine orange, two markers of the autophagic compartments such as autolysosomes. WIN also induced morphological effects in MG63 cells consisting in an increase in cell size and a marked cytoplasmic vacuolization. However, WIN effects were not associated with a canonical apoptotic pathway, as demonstrated by the absence of specific features, and only the addition of TRAIL to WIN-treated cells led to apoptotic death probably mediated by up-regulation of the tumor suppressor factor PAR-4, whose levels increased after WIN treatment, and by the translocation of GRP78 on cell surface. PMID:24795528

  15. Involvement of PAR-4 in cannabinoid-dependent sensitization of osteosarcoma cells to TRAIL-induced apoptosis.

    PubMed

    Notaro, Antonietta; Sabella, Selenia; Pellerito, Ornella; Di Fiore, Riccardo; De Blasio, Anna; Vento, Renza; Calvaruso, Giuseppe; Giuliano, Michela

    2014-01-01

    The synthetic cannabinoid WIN 55,212-2 is a potent cannabinoid receptor agonist with anticancer potential. Experiments were performed to determine the effects of WIN on proliferation, cell cycle distribution, and programmed cell death in human osteosarcoma MG63 and Saos-2 cells. Results show that WIN induced G2/M cell cycle arrest, which was associated with the induction of the main markers of ER stress (GRP78, CHOP and TRB3). In treated cells we also observed the conversion of the cytosolic form of the autophagosome marker LC3-I into LC3-II (the lipidated form located on the autophagosome membrane) and the enhanced incorporation of monodansylcadaverine and acridine orange, two markers of the autophagic compartments such as autolysosomes. WIN also induced morphological effects in MG63 cells consisting in an increase in cell size and a marked cytoplasmic vacuolization. However, WIN effects were not associated with a canonical apoptotic pathway, as demonstrated by the absence of specific features, and only the addition of TRAIL to WIN-treated cells led to apoptotic death probably mediated by up-regulation of the tumor suppressor factor PAR-4, whose levels increased after WIN treatment, and by the translocation of GRP78 on cell surface. PMID:24795528

  16. Alpha-CaMKII plays a critical role in determining the aggressive behavior of human osteosarcoma.

    PubMed

    Daft, Paul G; Yuan, Kaiyu; Warram, Jason M; Klein, Michael J; Siegal, Gene P; Zayzafoon, Majd

    2013-04-01

    Osteosarcoma is among the most frequently occurring primary bone tumors, primarily affecting adolescents and young adults. Despite improvements in osteosarcoma treatment, more specific molecular targets are needed as potential therapeutic options. One target of interest is α-Ca(2+)/calmodulin-dependent protein kinase II (α-CaMKII), a ubiquitous mediator of Ca(2+)-linked signaling, which has been shown to regulate tumor cell proliferation and differentiation. Here, we investigate the role of α-CaMKII in the growth and tumorigenicity of human osteosarcoma. We show that α-CaMKII is highly expressed in primary osteosarcoma tissue derived from 114 patients, and is expressed in varying levels in different human osteosarcoma (OS) cell lines [MG-63, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)/HOS, and 143B). To examine whether α-CaMKII regulates osteosarcoma tumorigenic properties, we genetically inhibited α-CaMKII in two osteosarcoma cell lines using two different α-CaMKII shRNAs delivered by lentiviral vectors and overexpressed α-CaMKII by retrovirus. The genetic deletion of α-CaMKII by short hairpin RNA (shRNA) in MG-63 and 143B cells resulted in decreased proliferation (50% and 41%), migration (22% and 25%), and invasion (95% and 90%), respectively. The overexpression of α-CaMKII in HOS cells resulted in increased proliferation (240%), migration (640%), and invasion (10,000%). Furthermore, α-CaMKII deletion in MG-63 cells significantly reduced tumor burden in vivo (65%), whereas α-CaMKII overexpression resulted in tumor formation in a previously nontumor forming osteosarcoma cell line (HOS). Our results suggest that α-CaMKII plays a critical role in determining the aggressive phenotype of osteosarcoma, and its inhibition could be an attractive therapeutic target to combat this devastating adolescent disease. PMID:23364534

  17. Advances in osteosarcoma stem cell research and opportunities for novel therapeutic targets.

    PubMed

    Yan, Guang-Ning; Lv, Yang-Fan; Guo, Qiao-Nan

    2016-01-28

    Osteosarcoma is the most common type of bone cancer, especially in children and young adults. The primary treatment for osteosarcoma is a combination of surgery and chemotherapy, however prognoses remain poor due to chemoresistance and early metastases. Osteosarcoma stem cells appear to play central roles in tumor recurrence, metastases and chemoresistance via self-renewal and differentiation. Targeting these cells may provide a novel strategy in the treatment of osteosarcoma. This review summarizes current knowledge of this rare phenotype and recent advances in understanding the functions OSCs (osteosarcoma stem cells) in osteosarcoma, with the aim of improving therapies in the future. PMID:26571463

  18. Coordinate regulation of fibronectin matrix assembly by the plasminogen activator system and vitronectin in human osteosarcoma cells

    PubMed Central

    Vial, Daniel; Monaghan-Benson, Elizabeth; McKeown-Longo, Paula J

    2006-01-01

    Background Plasminogen activators are known to play a key role in the remodeling of bone matrix which occurs during tumor progression, bone metastasis and bone growth. Dysfunctional remodeling of bone matrix gives rise to the osteoblastic and osteolytic lesions seen in association with metastatic cancers. The molecular mechanisms responsible for the development of these lesions are not well understood. Studies were undertaken to address the role of the plasminogen activator system in the regulation of fibronectin matrix assembly in the osteoblast-like cell line, MG-63. Results Treatment of MG-63 cells with P25, a peptide ligand for uPAR, resulted in an increase in assembly of fibronectin matrix which was associated with an increase in the number of activated β1 integrins on the cell surface. Overexpression of uPAR in MG-63 cells increased the effect of P25 on fibronectin matrix assembly and β1 integrin activation. P25 had no effect on uPAR null fibroblasts, confirming a role for uPAR in this process. The addition of plasminogen activator inhibitor Type I (PAI-1) to cells increased the P25-induced fibronectin polymerization, as well as the number of activated integrins. This positive regulation of PAI-1 on fibronectin assembly was independent of PAI-1's anti-proteinase activity, but acted through PAI-1 binding to the somatomedin B domain of vitronectin. Conclusion These results indicate that vitronectin modulates fibronectin matrix assembly in osteosarcoma cells through a novel mechanism involving cross-talk through the plasminogen activator system. PMID:16569238

  19. Vector-averaged gravity-induced changes in cell signaling and vitamin D receptor activity in MG-63 cells are reversed by a 1,25-(OH)2D3 analog, EB1089

    NASA Technical Reports Server (NTRS)

    Narayanan, R.; Smith, C. L.; Weigel, N. L.

    2002-01-01

    Skeletal unloading in an animal hindlimb suspension model and microgravity experienced by astronauts or as a result of prolonged bed rest causes site-specific losses in bone mineral density of 1%-2% per month. This is accompanied by reductions in circulating levels of 1,25-(OH)(2)D(3), the active metabolite of vitamin D. 1,25-(OH)(2)D(3), the ligand for the vitamin D receptor (VDR), is important for calcium absorption and plays a role in differentiation of osteoblasts and osteoclasts. To examine the responses of cells to activators of the VDR in a simulated microgravity environment, we used slow-turning lateral vessels (STLVs) in a rotating cell culture system. We found that, similar to cells grown in microgravity, MG-63 cells grown in the STLVs produce less osteocalcin, alkaline phosphatase, and collagen Ialpha1 mRNA and are less responsive to 1,25-(OH)(2)D(3). In addition, expression of VDR was reduced. Moreover, growth in the STLV caused activation of the stress-activated protein kinase pathway (SAPK), a kinase that inhibits VDR activity. In contrast, the 1,25-(OH)(2)D(3) analog, EB1089, was able to compensate for some of the STLV-associated responses by reducing SAPK activity, elevating VDR levels, and increasing expression of osteocalcin and alkaline phosphatase. These studies suggest that, not only does simulated microgravity reduce differentiation of MG-63 cells, but the activity of the VDR, an important regulator of bone metabolism, is reduced. Use of potent, less calcemic analogs of 1,25-(OH)(2)D(3) may aid in overcoming this defect. Copyright 2002 Elsevier Science Inc.

  20. A novel synthetic derivative of the natural product berbamine inhibits cell viability and induces apoptosis of human osteosarcoma cells, associated with activation of JNK/AP-1 signaling

    PubMed Central

    Yang, Fan; Nam, Sangkil; Zhao, Robin; Tian, Yan; Liu, Lucy; Horne, David A; Jove, Richard

    2013-01-01

    Osteosarcoma is the most common primary bone tumor in children and adolescents. There is a critical need to find more potent drugs for patients with metastatic or recurrent disease. Berbamine (BBM) is a natural compound derived from the Berberis amurensis plants. BBM and its derivatives have been shown to have antitumor effects in several cancers. Here, we report that a novel synthetic berbamine derivative, BBMD3, inhibits cell viability and induces apoptosis of G292, KHOS, and MG-63 human osteosarcoma cells. Induction of apoptosis in these tumor cells depends on activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase (PARP). Since pan-caspase inhibitor (Z-VAD-FMK) and caspase-9 inhibitor (Z-LEHD-FMK) could block the cleavage of PARP, the apoptosis induced by BBMD3 is through intrinsic signaling pathway. BBMD3 increased phosphorylation of c-Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK), resulting in increase of phosphorylated c-Jun and total c-Fos, the major components of transcriptional factor AP-1. JNK inhibitor could partially suppress antitumor effect of BBMD3 on osteosarcoma cells. BBMD3 increased the production of reactive oxygen species (ROS) and ROS scavenger, N-acetylcysteine (NAC), could block the phosphorylation of JNK and c-Jun induced by BBMD3. BBMD3 increased the expression of the pro-apototic gene Bad, associated with apoptosis induction. Finally, BBMD3 also decreased the expression of cyclin D1 and D2, the positive cell cycle regulators, which is correlated with growth inhibition in osteosarcoma cells. Collectively, these findings indicate that BBMD3 is a potentially promising drug for the treatment of human osteosarcoma. PMID:24025361

  1. A novel synthetic derivative of the natural product berbamine inhibits cell viability and induces apoptosis of human osteosarcoma cells, associated with activation of JNK/AP-1 signaling.

    PubMed

    Yang, Fan; Nam, Sangkil; Zhao, Robin; Tian, Yan; Liu, Lucy; Horne, David A; Jove, Richard

    2013-11-01

    Osteosarcoma is the most common primary bone tumor in children and adolescents. There is a critical need to find more potent drugs for patients with metastatic or recurrent disease. Berbamine (BBM) is a natural compound derived from the Berberis amurensis plants. BBM and its derivatives have been shown to have antitumor effects in several cancers. Here, we report that a novel synthetic berbamine derivative, BBMD3, inhibits cell viability and induces apoptosis of G292, KHOS, and MG-63 human osteosarcoma cells. Induction of apoptosis in these tumor cells depends on activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase (PARP). Since pan-caspase inhibitor (Z-VAD-FMK) and caspase-9 inhibitor (Z-LEHD-FMK) could block the cleavage of PARP, the apoptosis induced by BBMD3 is through intrinsic signaling pathway. BBMD3 increased phosphorylation of c-Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK), resulting in increase of phosphorylated c-Jun and total c-Fos, the major components of transcriptional factor AP-1. JNK inhibitor could partially suppress antitumor effect of BBMD3 on osteosarcoma cells. BBMD3 increased the production of reactive oxygen species (ROS) and ROS scavenger, N-acetylcysteine (NAC), could block the phosphorylation of JNK and c-Jun induced by BBMD3. BBMD3 increased the expression of the pro-apototic gene Bad, associated with apoptosis induction. Finally, BBMD3 also decreased the expression of cyclin D1 and D2, the positive cell cycle regulators, which is correlated with growth inhibition in osteosarcoma cells. Collectively, these findings indicate that BBMD3 is a potentially promising drug for the treatment of human osteosarcoma. PMID:24025361

  2. Diallyl trisulfide induces osteosarcoma cell apoptosis through reactive oxygen species-mediated downregulation of the PI3K/Akt pathway.

    PubMed

    Wang, Hongliang; Sun, Na; Li, Xin; Li, Ka; Tian, Jiguang; Li, Jianmin

    2016-06-01

    Diallyl trisulfide (DATS) is a natural organosulfur compound isolated from garlic, and has been reported to possess anticancer activities. However, the cancer growth inhibitory effects and molecular mechanisms in human osteosarcoma cells have not been well studied. The present study demonstrated that DATS significantly reduced cell viability in a dose- and time-dependent manner in MG63 and MNNG/HOS cells. DATS-induced G0/G1 phase arrest was found to correlate with a decrease in cyclin D1 in concomitance with an increase in p21 and p27. DATS induced a marked increase in reactive oxygen species (ROS) levels and collapse of mitochondrial membrane potential (Δψm) in the osteosarcoma cells. DATS induced apoptosis in the MG63 and MNNG/HOS cells via inhibition of the PI3K/Akt signaling pathway and through the mitochondrial apoptotic pathway. The efficiency of DATS basically approached the efficacy of LY294002, a specific PI3K inhibitor. However, N-acetylcysteine (NAC), a general ROS scavenger, completely blocked the DATS-induced ROS increase, inhibition of the PI3K/Akt pathway and cell apoptosis. Overall, DATS has the potential to be developed as a new anticancer drug. The mechanisms of action involve the ROS-mediated downregulation of the PI3K/Akt pathway. PMID:27035545

  3. Changes in the gene expression of co-cultured human fibroblast cells and osteosarcoma cells: the role of microenvironment

    PubMed Central

    Salvatore, Viviana; Focaroli, Stefano; Teti, Gabriella; Mazzotti, Antonio; Falconi, Mirella

    2015-01-01

    Background The progression of malignant tumors does not depend exclusively on the autonomous properties of cancer cells; it is also influenced by tumor stroma reactivity and is under strict microenvironmental control. By themselves, stromal cells are not malignant, and they maintain normal tissue structure and function. However, through intercellular interactions or by paracrine secretions from cancer cells, normal stromal cells acquire abnormal phenotypes that sustain cancer cell growth and tumor progression. In their dysfunctional state, fibroblast and immune cells produce chemokines and growth factors that stimulate cancer cell growth and invasion. In our previous work, we established an in vitro model based on a monolayer co-culture system of healthy human fibroblasts (HFs) and human osteosarcoma cells (the MG-63 cell line) that simulates the microenvironment of tumor cells and healthy cells. The coexistence between MG-63 cells and HFs allowed us to identify the YKL-40 protein as the main marker for verifying the influence of tumor cells grown in contact with healthy cells. Methods In this study, we evaluated the interactions of HFs and MG-63 cells in a transwell co-culture system over 24 h, 48 h, 72 h, and 96 h. We analyzed the contributions of these populations to the tumor microenvironment during cancer progression, as measured by multiple markers. We examined the effect of siRNA knockdown of YKL-40 by tracking the subsequent changes in gene expression within the co-culture. We validated the expression of several genes, focusing on those involved in cancer cell invasion, inflammatory responses, and angiogenesis: TNF alpha, IL-6, MMP-1, MMP-9, and VEGF. We compared the results to those from a transwell co-culture without the YKL-40 knockdown. Results In a pro-inflammatory environment promoted by TNF alpha and IL-6, siRNA knockdown of YKL-40 caused a down-regulation of VEGF and MMP-1 expression in HFs. Conclusions These findings demonstrated that the tumor

  4. Silencing of carboxypeptidase E inhibits cell proliferation, tumorigenicity, and metastasis of osteosarcoma cells

    PubMed Central

    Fan, Shuli; Li, Xu; Li, Leiming; Wang, Liguo; Du, Zhangzhen; Yang, Yan; Zhao, Jiansong; Li, Yan

    2016-01-01

    Carboxypeptidase E (CPE), a prohormone processing enzyme, has been implicated in the progression of multiple malignancies. However, the biological role and molecular mechanisms of CPE in osteosarcoma remain elusive. In this study, we assessed the effects of CPE on cell proliferation, tumorigenicity, migration, and invasion in osteosarcoma. Our results showed that silencing of CPE significantly inhibited cell proliferation, caused cell cycle arrest at G0/G1 phase, decreased the expression levels of cell cycle protein, cyclin D1, and inhibited tumorigenicity in vivo. Additionally, CPE downregulation repressed the migratory and invasive capacities of osteosarcoma cells in vitro. Furthermore, overexpression of CPE-ΔN (a splice variant of CPE) enhanced the cell growth, migration, and invasion of osteosarcoma cells. It is possible that both CPE forms are involved in the tumorigenesis and development of osteosarcoma, and therefore CPE may provide a promising biological target for osteosarcoma therapy. PMID:27274275

  5. Dodecyl gallate induces apoptosis by upregulating the caspase-dependent apoptotic pathway and inhibiting the expression of anti-apoptotic Bcl-2 family proteins in human osteosarcoma cells

    PubMed Central

    CHENG, CHUN-HSIANG; CHENG, YEN-PO; CHANG, ING-LIN; CHEN, HSIN-YAO; WU, CHIA-CHIEH; HSIEH, CHEN-PU

    2016-01-01

    Dodecyl gallate (DG) is a gallic acid ester that has been shown to inhibit tumor growth. The aim of this study was to investigate the mechanism by which DG induces antiproliferative and apoptotic effects in MG-63 human osteosarcoma cells. Dose- and time-dependent cytotoxic effects of DG were determined using an MTT assay. The results showed that the half-maximal inhibitory concentration (IC50) of DG in MG-63 cells was 31.15 µM at 24 h, 10.66 µM at 48 h, and 9.06 µM at 72 h. Flow cytometric analysis demonstrated that exposure to 20 and 40 µM DG resulted in an increase in the sub-G1 phase population and in S-phase cell cycle arrest. Furthermore, western blot analysis of apoptosis-related protein expression revealed an increase in the activation of caspases 8 and 3, cleavage of poly (ADPribose) polymerase (PARP), and disruption of mitochondrial membrane permeability was measured by flow cytometry. An increase in the Bax/Bcl-2 ratio and a decrease in the expression of inhibitor of apoptosis protein (IAP) family members, namely X-linked inhibitor of apoptosis protein and survivin, were also observed following DG treatment. These data provide insight into the molecular mechanisms governing the ability of DG to induce apoptosis in human osteosarcoma cells in vitro. PMID:26707422

  6. A preliminary optical and electron microscopic study of the beta(1) integrin distribution pattern of human osteosarcoma-derived cells.

    PubMed

    Banai, Kiarash; Brady, Ken; McDonald, Fraser

    2004-07-01

    Immunogold labelling was used to study the organisation of the beta(1) integrins on osteosarcoma-derived osteoblasts (Saos-2 and MG-63). Monolayers of cells were prepared in multiwell culture plates on both uncovered and collagen-covered coverslips, and beta(1) integrins were primarily labelled using mouse monoclonal antibodies to beta(1) integrins. Indirect immunofluorescence labels using an anti-mouse fluorescein-conjugated goat antibody showed an even distribution of the beta(1) integrins on the cell membranes of all cell types used. A concentration of 2 microg/ml of the primary antibodies and a 1:100 dilution of the secondary antibodies were determined as the optimal concentration for labelling to use with indirect localisation of the primary antibodies gold conjugated to goat anti-mouse antibodies and viewed under an electron microscope. Ten nanometre gold particles were used for transmission electron microscopy (TEM) and 40 nm gold particles for scanning electron microscopy. TEM showed that beta(1) integrins were mainly clustered on the cell membrane processes with less labelling on the cell membranes themselves. The distribution of beta(1) integrins on osteosarcoma cells supports the concept that integrins may function by forming focal adhesions at the site of the cytoplasmic membrane processes. PMID:15241608

  7. Comparative study of cytotoxicity of detonation nanodiamond particles with an osteosarcoma cell line and primary mesenchymal stem cells

    PubMed Central

    Keremidarska, Milena; Ganeva, Aneliya; Mitev, Dimitar; Hikov, Todor; Presker, Radina; Pramatarova, Lilyana; Krasteva, Natalia

    2014-01-01

    Recently, nanodiamonds (NDs) have attracted great interest due to their unique physical and chemical properties that could be used in various biological applications. However, depending on the origin, NDs often contain different impurities which may affect cellular functions and viability. Therefore, before their biomedical application, the cytotoxicity of newly produced NDs should be assessed. In the present study, we have evaluated cytotoxicity of four types of ND particles with two cell models: a human osteosarcoma cell line, MG-63, and primary rat mesenchymal stem cells (rMSCs). Detonation-generated nanodiamond (DND) particles were purified with different acid oxidizers and impurities’ content was determined by elemental analysis. The particles size distribution was measured revealing that the DND particles have an average size in the range of 51–233 nm. Cytotoxicity was assessed by optical microscopy and proliferation assay after 72 hours exposure of the cells to nanoparticles. We observed cell-specific and material-specific toxicity for all tested particles. Primary stem cells demonstrated higher sensitivity to DND particles than osteosarcoma cells. The most toxic were the DND particles with the smallest grain size and slight content of non-diamond carbon, while DNDs with higher grain size and free from impurities had no significant influence on cell proliferation and morphology. In addition, the smaller DND particles were found to form large aggregates mainly during incubation with rMSCs. These results demonstrate the role of the purification method on the properties of DND particles and their cytotoxicity as well as the importance of cell types used for evaluation of the nanomaterials. PMID:26019557

  8. Multimodal transfer of MDR by exosomes in human osteosarcoma.

    PubMed

    Torreggiani, Elena; Roncuzzi, Laura; Perut, Francesca; Zini, Nicoletta; Baldini, Nicola

    2016-07-01

    Exosomes are extracellular vesicles released by both normal and tumour cells which are involved in a new intercellular communication pathway by delivering cargo (e.g., proteins, microRNAs, mRNAs) to recipient cells. Tumour-derived exosomes have been shown to play critical roles in different stages of tumour growth and progression. In this study, we investigated the potential role of exosomes to transfer the multidrug resistance (MDR) phenotype in human osteosarcoma cells. Exosomes were isolated by differential centrifugation of culture media from multidrug resistant human osteosarcoma MG-63DXR30 (Exo/DXR) and MG-63 parental cells (Exo/S). Exosome purity was examined by transmission electron microscopy and confirmed by immunoblot analysis for the expression of specific exosomal markers. Our data showed that exosomes derived from doxorubicin-resistant osteosarcoma cells could be taken up into secondary cells and induce a doxorubicin-resistant phenotype. The incubation of osteosarcoma cells with Exo/DXR decreased the sensitivity of parental cells to doxorubicin, while exposure with Exo/S was ineffective. In addition, we demonstrated that Exo/DXR expressed higher levels of MDR-1 mRNA and P-glycoprotein compared to Exo/S (p=0.03). Interestingly, both MDR-1 mRNA and P-gp increased in MG-63 cells after incubation with Exo/DXR, suggesting this as the main mechanism of exosome-mediated transfer of drug resistance. Our findings suggest that multidrug resistant osteosarcoma cells are able to spread their ability to resist the effects of doxorubicin treatment on sensitive cells by transferring exosomes carrying MDR-1 mRNA and its product P-glycoprotein. PMID:27176642

  9. Potentiation of the antitumor activity of adriamycin against osteosarcoma by cannabinoid WIN-55,212-2

    PubMed Central

    NIU, FENG; ZHAO, SONG; XU, CHANG-YAN; SHA, HUI; BI, GUI-BIN; CHEN, LIN; YE, LONG; GONG, PING; NIE, TIAN-HONG

    2015-01-01

    Osteosarcoma is the most frequent primary malignant bone tumor that occurs in children and adolescents. The present study aimed to identify novel therapeutic strategies for osteosarcoma, by assessing the antitumor activity of the cannabinoid WIN-55,212-2 and its combined effect with adriamycin (ADM) against the MG-63 human osteosarcoma cell line. To evaluate the antiproliferative action of these molecules, a Cell Counting kit-8 (CCK-8) assay was used. The ability of cannabinoid to inhibit the migration, invasion and angiogenic activity of MG-63 cells were assessed by scratch, Transwell® chamber and angiogenesis assays, respectively, in vitro. To examine the alterations in expression of targeted genes, quantitative polymerase chain reaction and western blot analysis were used. The administration of cannabinoid combined with ADM was demonstrated to inhibit the growth of MG-63 cells, resulting in a cell viability of 32.12±3.13%, which was significantly lower (P<0.05) compared with the cell viability following treatment with cannabinoid (70.86±7.55%) and ADM (62.87±5.98%) alone. Greater antimetastasis and antiangiogenic activities were also observed following the coadministration of the two agents compared with individual treatments and controls. In addition, the expression levels of Notch-1, matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF) in MG-63 cells were downregulated following the treatments with cannabinoid alone or in combination with ADM. In conclusion, the present findings demonstrated that cannabinoid WIN-55,212-2 may significantly potentiate the antiproliferative, antimetastasis and antiangiogenic effects of ADM against MG-63 cells via the downregulation of Notch-1, MMP-2 and VEGF. These findings may offer a novel strategy for the treatment of osteosarcoma. PMID:26622862

  10. The secreted protein acidic and rich in cysteine is a critical mediator of cell death program induced by WIN/TRAIL combined treatment in osteosarcoma cells.

    PubMed

    Notaro, Antonietta; Sabella, Selenia; Pellerito, Ornella; Vento, Renza; Calvaruso, Giuseppe; Giuliano, Michela

    2016-03-01

    Secreted protein acidic and rich in cysteine (SPARC) is a multi-functional protein which modulates cell-cell and cell-matrix interactions. In cancer cells, SPARC behaves as a tumor promoter in a number of tumors, but it can also act as a tumor suppressor factor. Our previous results showed that the synthetic cannabinoid WIN55,212-2 (WIN), a potent cannabinoid receptor agonist, is able to sensitize osteosarcoma MG63 cells to TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis which is accompanied with endoplasmic reticulum (ER)-stress induction and the increase in autophagic markers. In the present investigation, we studied the role of SPARC in WIN/TRAIL-induced apoptosis demonstrating that WIN increased the level of SPARC protein and mRNA in a time-dependent manner. This event was functional to WIN/TRAIL-dependent apoptosis as demonstrated by RNA interfering analysis which indicated that SPARC-silenced cells were less sensitive to cytotoxic effects induced by the combined treatment. Our experiments also demonstrate that SPARC interacts with caspase-8 thus probably favoring its translocation to plasma membrane and the activation of extrinsic apoptotic pathway. In conclusion, to the best of our knowledge, our results are the first to show that WIN-dependent increase in the level of SPARC plays a critical role in sensitizing osteosarcoma cells to TRAIL action. PMID:26698404

  11. Focal adhesion kinase overexpression and its impact on human osteosarcoma

    PubMed Central

    Chen, Yong; Yang, Aizhen; Chen, Hui; Zhang, Jian; Wu, Sujia; Shi, Xin; Wang, Chen; Sun, Xiaoliang

    2015-01-01

    Focal adhesion kinase (FAK) has been implicated in tumorigenesis in various malignancies. We sought to examine the expression patterns of FAK and the activated form, phosphorylated FAK (pFAK), in human osteosarcoma and to investigate the correlation of FAK expression with clinicopathologic parameters and prognosis. In addition, the functional consequence of manipulating the FAK protein level was investigated in human osteosarcoma cell lines. Immunohistochemical staining was used to detect FAK and pFAK in pathologic archived materials from 113 patients with primary osteosarcoma. Kaplan-Meier survival and Cox regression analyses were performed to evaluate the prognoses. The role of FAK in the cytological behavior of MG63 and 143B human osteosarcoma cell lines was studied via FAK protein knock down with siRNA. Cell proliferation, migration, invasiveness and apoptosis were assessed using the CCK8, Transwell and Annexin V/PI staining methods. Both FAK and pFAK were overexpressed in osteosarcoma. There were significant differences in overall survival between the FAK-/pFAK- and FAK+/pFAK- groups (P = 0.016), the FAK+/pFAK- and FAK+/pFAK+ groups (P = 0.012) and the FAK-/pFAK- and FAK+/pFAK+ groups (P < 0.001). There were similar differences in metastasis-free survival between groups. The Cox proportional hazards analysis showed that the FAK expression profile was an independent indicator of both overall and metastasis-free survival. siRNA-based knockdown of FAK not only dramatically reduced the migration and invasion of MG63 and 143B cells, but also had a distinct effect on osteosarcoma cell proliferation and apoptosis. These results collectively suggest that FAK overexpression and phosphorylation might predict more aggressive biologic behavior in osteosarcoma and may be an independent predictor of poor prognosis. PMID:26393679

  12. Osteosarcoma: mouse models, cell of origin and cancer stem cell

    PubMed Central

    Guijarro, Maria V.

    2016-01-01

    Osteosarcoma (OS) is the most common non-hematologic primary tumor of bone in children and adults. High-dose cytotoxic chemotherapy and surgical resection have improved prognosis, with long-term survival for non-metastatic disease approaching 70%. However, most OS tumors are high grade and tend to rapidly develop pulmonary metastases. Despite clinical advances, patients with metastatic disease or relapse have a poor prognosis. Here the cell biology of OS is reviewed with a special emphasis on mouse models as well as the roles of the cell of origin and cancer stem cells. A better understanding of the molecular pathogenesis of human OS is essential for the development of improved prognostic and diagnostic markers as well as targeted therapies for both primary and metastatic OS.

  13. Paroxetine-induced apoptosis in human osteosarcoma cells: Activation of p38 MAP kinase and caspase-3 pathways without involvement of [Ca{sup 2+}]{sub i} elevation

    SciTech Connect

    Chou, C.-T.; He Shiping; Jan, C.-R. . E-mail: crjan@isca.vghks.gov.tw

    2007-02-01

    Selective serotonin reuptake inhibitors (SSRIs), a group of antidepressants, are generally used for treatment of various mood and anxiety disorders. There has been much research showing the anti-tumor and cytotoxic activities of some antidepressants; but the detailed mechanisms were unclear. In cultured human osteosarcoma cells (MG63), paroxetine reduced cell viability in a concentration- and time-dependent manner. Paroxetine caused apoptosis as assessed by propidium iodide-stained cells and increased caspase-3 activation. Although immunoblotting data revealed that paroxetine could activate the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun NH{sub 2}-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK), only SB203580 (a p38 MAPK inhibitor) partially prevented cells from apoptosis. Paroxetine also induced [Ca{sup 2+}]{sub i} increases which involved the mobilization of intracellular Ca{sup 2+} stored in the endoplasmic reticulum and Ca{sup 2+} influx from extracellular medium. However, pretreatment with BAPTA/AM, a Ca{sup 2+} chelator, to prevent paroxetine-induced [Ca{sup 2+}]{sub i} increases did not protect cells from death. The results suggest that in MG63 cells, paroxetine caused Ca{sup 2+}-independent apoptosis via inducing p38 MAPK-associated caspase-3 activation.

  14. MicroRNA-603 functions as an oncogene by suppressing BRCC2 protein translation in osteosarcoma.

    PubMed

    Ma, Chengbin; Zhan, Chuan; Yuan, Hongmou; Cui, Yan; Zhang, Zhiyu

    2016-06-01

    The present study was conducted to investigate the expression of miR-603 in osteosarcoma cells, and the effect of miR-603 on the biological behavior and expression of breast cancer cell 2 (BRCC2) in osteosarcoma cells. In the present study, qRT-PCR was used to measure the levels of miRNA and mRNA. The results showed that miR-603 was significantly upregulated in human osteosarcoma tissues and cell lines. MTT and colony formation assays were employed to evaluate the role of miR-603 in the regulation of osteosarcoma cell proliferation. The results showed that overexpression of miR-603 promoted the proliferation of MG-63 and U2OS cells. Furthermore, a nude mouse subcutaneous tumor model indicated that miR-603 promoted osteosarcoma growth in vivo. Moreover, miR-603 expression levels were increased in patients with distant metastasis in comparison with levels in patients without distant metastasis. We discovered that BRCC2 may be a target of miR-603. Our results demonstrated that overexpression of miR-603 suppressed BRCC2 protein expression, and an miR-603 inhibitor enhanced BRCC2 protein expression as determined by western blot assay and immunohistochemical analysis. Luciferase reporter assays confirmed that BRCC2 is a direct target of miR-603 in osteosarcoma cells, and the results suggest that miR-603 downregulates BRCC2 expression in osteosarcoma via translational inhibition. Finally, we found that the reduction in BRCC2 expression induced by miR-603 was responsible for the enhanced colony formation and proliferative ability noted in the MG-63 and U2OS cells. In conclusion, miR-603 enhanced osteosarcoma growth by downregulation of BRCC2 expression via translational inhibition. PMID:27035098

  15. The survivin suppressant YM155 reverses doxorubicin resistance in osteosarcoma.

    PubMed

    Zhang, Zhuo; Zhang, Yunfeng; Lv, Jiayin; Wang, Jincheng

    2015-01-01

    Doxorubicin (DOX) is one of the widely used chemotherapeutic drugs for the treatment of human osteosarcoma (OS). However, acquisition of DOX resistance is common in patients with OS, leading to local and distant failure. In this study, we demonstrate that survivin expression is significantly upregulated in OS primary tumors compared to paired normal tissue. In addition, survivin expression was further increased in DOX resistant cells (MG63/DOX) as compared to its parent cells (MG63). Thus, we hypothesize that targeting of survivin in OS could reverse the DOX resistant phenotype in tumor cells thereby enhancing the therapeutic efficacy of DOX. We test the efficacy of YM155, a small molecule survivin inhibitor, either as a single agent or in combination with DOX in vitro and in vivo. We found that combination treatment of YM155 and DOX in DOX resistant cells (MG63/DOX) could significantly inhibited cell proliferation and colony formation, induce cell apoptosis and promoted caspase-3, -8, and -9 activity in vitro, and promoted tumor regression in established OS xenograft models. Taken together, the evidence presented here supports the favorable preclinical evaluation that YM155 could overcome DOX the resistance in tumor cells thereby enhancing the effectiveness of DOX in OS, suggesting that YM155 in combination with DOX has potential in the treatment of osteosarcoma. PMID:26770398

  16. The survivin suppressant YM155 reverses doxorubicin resistance in osteosarcoma

    PubMed Central

    Zhang, Zhuo; Zhang, Yunfeng; Lv, Jiayin; Wang, Jincheng

    2015-01-01

    Doxorubicin (DOX) is one of the widely used chemotherapeutic drugs for the treatment of human osteosarcoma (OS). However, acquisition of DOX resistance is common in patients with OS, leading to local and distant failure. In this study, we demonstrate that survivin expression is significantly upregulated in OS primary tumors compared to paired normal tissue. In addition, survivin expression was further increased in DOX resistant cells (MG63/DOX) as compared to its parent cells (MG63). Thus, we hypothesize that targeting of survivin in OS could reverse the DOX resistant phenotype in tumor cells thereby enhancing the therapeutic efficacy of DOX. We test the efficacy of YM155, a small molecule survivin inhibitor, either as a single agent or in combination with DOX in vitro and in vivo. We found that combination treatment of YM155 and DOX in DOX resistant cells (MG63/DOX) could significantly inhibited cell proliferation and colony formation, induce cell apoptosis and promoted caspase-3, -8, and -9 activity in vitro, and promoted tumor regression in established OS xenograft models. Taken together, the evidence presented here supports the favorable preclinical evaluation that YM155 could overcome DOX the resistance in tumor cells thereby enhancing the effectiveness of DOX in OS, suggesting that YM155 in combination with DOX has potential in the treatment of osteosarcoma. PMID:26770398

  17. Genetically Modified T-Cell Therapy for Osteosarcoma

    PubMed Central

    DeRenzo, Christopher

    2015-01-01

    T-cell immunotherapy may offer an approach to improve outcomes for patients with osteosarcoma, who fail current therapies. In addition, it has the potential to reduce treatment-related complications for all patients. Generating tumor-specific T cells with conventional antigen presenting cells ex vivo is time consuming and often results in T-cell products with a low frequency of tumor-specific T cells. In addition, the generated T cells remain sensitive to the immunosuppressive tumor microenvironment. Genetic modification of T cells is one strategy to overcome these limitations. For example, T cells can be genetically modified to render them antigen specific, resistant to inhibitory factors, or increase their ability to home to tumor sites. Most genetic modification strategies have only been evaluated in preclinical models, however early phase clinical trials are in progress. In this chapter we review the current status of gene-modified T-cell therapy with special focus on osteosarcoma, highlighting potential antigenic targets, preclinical and clinical studies, and strategies to improve current T-cell therapy approaches. PMID:24924183

  18. Effects of the surface characteristics of nanoporous titanium oxide films on Ti-24Nb-4Zr-8Sn alloy on the initial adhesion of osteoblast-like MG-63 cells

    PubMed Central

    HAO, YUQUAN; LI, SHUJUN; HAN, XUESONG; HAO, YULIN; AI, HONGJUN

    2013-01-01

    The aim of the present study was to investigate the effects of the surface characteristics of nanoporous titanium oxide films, formed by anodization on Ti-24Nb-4Zr-8Sn (Ti2448) alloy, on the early adhesion of osteoblast-like MG-63 cells. Nanoporous titanium oxide films with two different pore sizes (30 and 90 nm) were formed by anodization in NH4F solution on Ti2448 alloy. The surface roughness of the nanoporous titanium oxide films was determined using a Surftest Formtracer and field emission scanning electron microscopy (FESEM). Cell viability was evaluated at different time points using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. To investigate the regulatory mechanisms involved in the focal adhesion of osteoblasts to Ti2448 alloy, we quantified the expression levels of integrin β1 and paxillin mRNAs on the nanoporous titanium oxide films during early osteoblast adhesion using real-time RT-PCR. Samples with a 30-nm nanoporous film exhibited a greater number of overlapping microporous structures with microprojections compared with the 90-nm nanoporous film samples. The MTT assay indicated that cell viability on the 30-nm nanoporous surface following 24 and 48 h of cell culture was higher than those observed on the unanodized control and 90-nm nanoporous surfaces. Integrin β1 mRNA expression levels on the 30-nm nanoporous surface following cell culture for 48 h were also significantly higher compared with those on the unanodized control and 90-nm nanoporous surfaces. The results demonstrated that a 30-nm nanoporous titanium oxide film on Ti2448 alloy may provide the optimum bioactive implant surface for the initial adhesion of osteoblasts. PMID:23935754

  19. Effects of the surface characteristics of nanoporous titanium oxide films on Ti-24Nb-4Zr-8Sn alloy on the initial adhesion of osteoblast-like MG-63 cells.

    PubMed

    Hao, Yuquan; Li, Shujun; Han, Xuesong; Hao, Yulin; Ai, Hongjun

    2013-07-01

    The aim of the present study was to investigate the effects of the surface characteristics of nanoporous titanium oxide films, formed by anodization on Ti-24Nb-4Zr-8Sn (Ti2448) alloy, on the early adhesion of osteoblast-like MG-63 cells. Nanoporous titanium oxide films with two different pore sizes (30 and 90 nm) were formed by anodization in NH4F solution on Ti2448 alloy. The surface roughness of the nanoporous titanium oxide films was determined using a Surftest Formtracer and field emission scanning electron microscopy (FESEM). Cell viability was evaluated at different time points using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. To investigate the regulatory mechanisms involved in the focal adhesion of osteoblasts to Ti2448 alloy, we quantified the expression levels of integrin β1 and paxillin mRNAs on the nanoporous titanium oxide films during early osteoblast adhesion using real-time RT-PCR. Samples with a 30-nm nanoporous film exhibited a greater number of overlapping microporous structures with microprojections compared with the 90-nm nanoporous film samples. The MTT assay indicated that cell viability on the 30-nm nanoporous surface following 24 and 48 h of cell culture was higher than those observed on the unanodized control and 90-nm nanoporous surfaces. Integrin β1 mRNA expression levels on the 30-nm nanoporous surface following cell culture for 48 h were also significantly higher compared with those on the unanodized control and 90-nm nanoporous surfaces. The results demonstrated that a 30-nm nanoporous titanium oxide film on Ti2448 alloy may provide the optimum bioactive implant surface for the initial adhesion of osteoblasts. PMID:23935754

  20. Establishment of a cell line producing bone morphogenetic protein from a human osteosarcoma.

    PubMed

    Takaoka, K; Yoshikawa, H; Masuhara, K; Sugamoto, K; Tsuda, T; Aoki, Y; Ono, K; Sakamoto, Y

    1989-07-01

    A human osteosarcoma cell line was established from a biopsy specimen from a 13-year-old girl. The osteosarcoma tissue was maintained in athymic nude mice (Balb C nu/nu) by serial transplantation for three years. The tumor was excised from a host mouse and digested with collagenase. The isolated cells were cultured by 98 passages in 14 months, and clones of osteosarcoma cells were obtained by limiting dilution. A clone named human osteosarcoma cell 6 (H-OS-6) that showed the osteoblastic phenotypes of productions of bone morphogenetic protein (BMP) and alkaline phosphatase and a response to human parathyroid hormone (h-PTH 1-34) was selected. The morphology of its chromosomes indicated its human origin. This human osteosarcoma cell line is unique in producing BMP under in vitro conditions. PMID:2545399

  1. Targeting CDK11 in osteosarcoma cells using the CRISPR-Cas9 system

    PubMed Central

    Feng, Yong; Sassi, Slim; Shen, Jacson K; Yang, Xiaoqian; Gao, Yan; Osaka, Eiji; Zhang, Jianming; Yang, Shuhua; Yang, Cao; Mankin, Henry J.; Hornicek, Francis J; Duan, Zhenfeng

    2014-01-01

    Osteosarcoma is the most common type primary malignant tumor of bone. Patients with regional osteosarcoma are routinely treated with surgery and chemotherapy. In addition, many patients with metastatic or recurrent osteosarcoma show poor prognosis with current chemotherapy agents. Therefore, it is important to improve the general condition and the overall survival rate of patients with osteosarcoma by identifying novel therapeutic strategies. Recent studies have revealed that CDK11 is essential in osteosarcoma cell growth and survival by inhibiting CDK11 mRNA expression with RNAi. Here, we apply the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9 system, a robust and highly efficient novel genome editing tool, to determine the effect of targeting endogenous CDK11 gene at the DNA level in osteosarcoma cell lines. We show that CDK11 can be efficiently silenced by CRISPR-Cas9. Inhibition of CDK11 is associated with decreased cell proliferation and viability, and induces cell death in osteosarcoma cell lines KHOS and U-2OS. Furthermore, the migration and invasion activities are also markedly reduced by CDK11 knockout. These results demonstrate that CRISPR-Cas9 system is a useful tool for the modification of endogenous CDK11 gene expression, and CRISPR-Cas9 targeted CDK11 knockout may be a promising therapeutic regimen for the treatment of osteosarcoma. PMID:25348612

  2. A beta-lactone related to lactacystin induces neurite outgrowth in a neuroblastoma cell line and inhibits cell cycle progression in an osteosarcoma cell line.

    PubMed Central

    Fenteany, G; Standaert, R F; Reichard, G A; Corey, E J; Schreiber, S L

    1994-01-01

    Lactacystin, a microbial natural product, induces neurite outgrowth in Neuro 2A mouse neuroblastoma cells and inhibits progression of synchronized Neuro 2A cells and MG-63 human osteosarcoma cells beyond the G1 phase of the cell cycle. A related beta-lactone, clasto-lactacystin beta-lactone, formally the product of elimination of N-acetylcysteine from lactacystin, is also active, whereas the corresponding clastolactacystin dihydroxy acid is completely inactive. Structural analogs of lactacystin altered only in the N-acetylcysteine moiety are active, while structural or stereochemical modifications of the gamma-lactam ring or the hydroxyisobutyl group lead to partial or complete loss of activity. The inactive compounds do not antagonize the effects of lactacystin in either neurite outgrowth or cell cycle progression assays. The response to lactacystin involves induction of a predominantly bipolar morphology that is maximal 16-32 h after treatment and is distinct from the response to several other treatments that result in morphological differentiation. Neurite outgrowth in response to lactacystin appears to be dependent upon microtubule assembly, actin polymerization, and de novo protein synthesis. The observed structure-activity relationships suggest that lactacystin and its related beta-lactone may act via acylation of one or more relevant target molecule(s) in the cell. Images PMID:8159752

  3. TRIM66 overexpresssion contributes to osteosarcoma carcinogenesis and indicates poor survival outcome

    PubMed Central

    Chen, Yu; Guo, Yongfei; Yang, Haisong; Shi, Guodong; Xu, Guohua; Shi, Jiangang; Na, Yin; Chen, Deyu

    2015-01-01

    TRIM66 belongs to the family of tripartite motif (TRIM)-containing proteins. Alterations in TRIM proteins have been implicated in several malignancies. This study was aimed at elucidating the expression and biological function of TRIM66 in osteosarcoma. Here, TRIM66 expression level was higher in osteosarcoma tissues than in normal tissues. High TRIM66 expression was correlated with high rate of local recurrence and lung metastasis, and short survival time. Then, we found that knockdown of TRIM66 in two osteosarcoma cell lines, MG63 and HOS, significantly inhibited cell proliferation and induced G1-phase arrest. Moreover, inhibition of TRIM66 in osteosarcoma cells significantly induced cell apoptosis, while remarkably inhibited cell migration, invasion as well as tumorigenicity in nude mice. Gene set enrichment analysis in Gene Expression Omnibus dataset revealed that apoptosis, epithelial-mesenchymal transition (EMT) and transforming growth factor-β (TGF-β) signaling pathway-related genes were enriched in TRIM66 higher expression patients, which was confirmed by western blot analysis in osteosarcoma cells with TRIM66 silenced. In conclusion, TRIM66 may act as an oncogene through suppressing apoptosis pathway and promoting TGF-β signaling in osteosarcoma carcinogenesis. TRIM66 may be a prognostic factor and potential therapeutic target in osteosarcoma. PMID:26247633

  4. Zoledronate blocks geranylgeranylation not farnesylation to suppress human osteosarcoma U2OS cells metastasis by EMT via Rho A activation and FAK-inhibited JNK and p38 pathways.

    PubMed

    Cheng, Hsin-Lin; Lin, Chiao-Wen; Yang, Jia-Sin; Hsieh, Ming-Ju; Yang, Shun-Fa; Lu, Ko-Hsiu

    2016-03-01

    Zoledronate is a standard treatment for preventing skeletal complications of osteoporosis and some types of cancer associated with bone metastases, but we little know whether the effect of zoledronate on metastasis of osteosarcoma. Here, we investigated the inhibitory effects of zoledronate on cell viability, motility, migration and invasion of 4 osteosarcoma cell lines (Saos2, MG-63, HOS and U2OS) by affecting cell morphology, epithelial-mesenchymal transition (EMT) and cytoskeletal organization as well as induction of E-cadherin and reduction of N-cadherin with activation of transcription factors Slug and Twist, especially in U2OS cells. Zoledronate decreased JNK and p38 phosphorylation and upper streams of focal adhesion kinase (FAK) and Src to suppress the motility, invasiveness and migration of U2OS cells. In addition to zoledronate-inhibited Rho A and Cdc42 membrane translocation and GTPγS activities, the anti-metastatic effects in U2OS cells including inhibition of adhesion were reversed by geranylgeraniol, but not farnesol. In conclusion, Zoledronate blocks geranylgeranylation not farnesylation to suppress human osteosarcoma U2OS cell-matrix and cell-cell interactions, migration potential, the invasive activity, and the adhesive ability by EMT via Rho A activation and FAK-inhibited JNK and p38 pathways. PMID:26848867

  5. Zoledronate blocks geranylgeranylation not farnesylation to suppress human osteosarcoma U2OS cells metastasis by EMT via Rho A activation and FAK-inhibited JNK and p38 pathways

    PubMed Central

    Cheng, Hsin-Lin; Lin, Chiao-Wen; Yang, Jia-Sin; Hsieh, Ming-Ju; Yang, Shun-Fa; Lu, Ko-Hsiu

    2016-01-01

    Zoledronate is a standard treatment for preventing skeletal complications of osteoporosis and some types of cancer associated with bone metastases, but we little know whether the effect of zoledronate on metastasis of osteosarcoma. Here, we investigated the inhibitory effects of zoledronate on cell viability, motility, migration and invasion of 4 osteosarcoma cell lines (Saos2, MG-63, HOS and U2OS) by affecting cell morphology, epithelial-mesenchymal transition (EMT) and cytoskeletal organization as well as induction of E-cadherin and reduction of N-cadherin with activation of transcription factors Slug and Twist, especially in U2OS cells. Zoledronate decreased JNK and p38 phosphorylation and upper streams of focal adhesion kinase (FAK) and Src to suppress the motility, invasiveness and migration of U2OS cells. In addition to zoledronate-inhibited Rho A and Cdc42 membrane translocation and GTPγS activities, the anti-metastatic effects in U2OS cells including inhibition of adhesion were reversed by geranylgeraniol, but not farnesol. In conclusion, Zoledronate blocks geranylgeranylation not farnesylation to suppress human osteosarcoma U2OS cell-matrix and cell-cell interactions, migration potential, the invasive activity, and the adhesive ability by EMT via Rho A activation and FAK-inhibited JNK and p38 pathways. PMID:26848867

  6. Decitabine-induced demethylation of 5' CpG island in GADD45A leads to apoptosis in osteosarcoma cells.

    PubMed

    Al-Romaih, Khaldoun; Sadikovic, Bekim; Yoshimoto, Maisa; Wang, Yuzhuo; Zielenska, Maria; Squire, Jeremy A

    2008-05-01

    GADD45 genes are epigenetically inactivated in various types of cancer and tumor cell lines. To date, defects of the GADD45 gene family have not been implicated in osteosarcoma (OS) oncogenesis, and the role of this pathway in regulating apoptosis in this tumor is unknown. The therapeutic potential of Gadd45 in OS emerged when our previous studies showed that GADD45A was reexpressed by treatment with the demethylation drug decitabine. In this study, we analyze the OS cell lines MG63 and U2OS and show that on treatment with decitabine, a significant loss of DNA methylation of GADD45A was associated with elevated expression and induction of apoptosis. In vivo affects of decitabine treatment in mice showed that untreated control xenografts exhibited low nuclear staining for Gadd45a protein, whereas the nuclei from xenografts in decitabine-treated mice exhibited increased amounts of protein and elevated apoptosis. To show the specificity of this gene for decitabine-induced apoptosis in OS, GADD45A mRNAs were disrupted using short interference RNA, and the ability of the drug to induce apoptosis was reduced. Understanding the role of demethylation of GADD45A in reexpression of this pathway and restoration of apoptotic control is important for understanding OS oncogenesis and for more targeted therapeutic approaches. PMID:18472964

  7. Plumbagin exhibits an anti-proliferative effect in human osteosarcoma cells by downregulating FHL2 and interfering with Wnt/β-catenin signalling

    PubMed Central

    Xue, Yuan-Liang; Meng, Xiang-Qi; Ma, Long-Jun; Yuan, Zhen

    2016-01-01

    Plumbagin, a naphthoquinone constituent of Plumbago zeylanica L. (Plumbaginaceae) is widely used in traditional Chinese medicine as an antifungal, antibacterial and anti-inflammatory agent. Plumbagin is known to exhibit proapoptotic, antiangiogenic and antimetastatic effects in cancer cells. The transcriptional co-factor four and a half LIM domains 2 (FHL2) is a multifunctional adaptor protein that is involved in the regulation of gene expression, signal transduction and cell proliferation and differentiation, and also acts as a tumor suppressor or oncoprotein depending on the tissue microenvironment. The present study investigated the effect of plumbagin on FHL2 expression, Wnt/β-catenin signalling and its anti-proliferative activity in various human osteosarcoma cell lines, including SaOS2, MG63, HOS and U2OS. The cells were exposed to plumbagin and the expression of FHL2 was evaluated using western blot analysis. Furthermore, the anti-proliferative effect of plumbagin was evaluated using a 3-(4,5 dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. In addition, since FHL2 is involved in Wnt/β-catenin signaling, the effect of plumbagin on β-catenin and its primary target genes, including v-myc avian myelocytomatosis viral oncogene homolog (c-Myc) and WNT1 inducible signaling pathway protein-1 (WISP-1), was evaluated using western blot analysis. It was observed that plumbagin suppressed the expression of FHL2 and exhibited significant anti-proliferative activity in osteosarcoma cells. It also attenuated Wnt/β-catenin signalling by downregulating β-catenin and its target genes, including c-Myc and WISP-1. In conclusion, plumbagin demonstrated anti-proliferative activity in osteosarcoma cells by downregulating FHL2 and interfering with Wnt/β-catenin signalling. PMID:27446400

  8. Cells of origin in osteosarcoma: mesenchymal stem cells or osteoblast committed cells?

    PubMed

    Mutsaers, Anthony J; Walkley, Carl R

    2014-05-01

    Osteosarcoma is a disease with many complex genetic abnormalities but few well defined genetic drivers of tumor initiation and evolution. The disease is diagnosed and defined through the observation of malignant osteoblastic cells that produce osteoid, however the exact cell of origin for this cancer remains to be definitively defined. Evidence exists to support a mesenchymal stem cell as well as committed osteoblast precursors as the cell of origin. Increasing numbers of experimental models have begun to shed light on to the likely cell population that gives rise to OS in vivo with the weight of evidence favoring an osteoblastic population as the cell of origin. As more information is gathered regarding osteosarcoma initiating cells and how they may relate to the cell of origin we will derive a better understanding of the development of this disease which may ultimately lead to clinical improvements through more personalized therapeutic approaches. PMID:24530473

  9. Osteocytes serve as a progenitor cell of osteosarcoma

    PubMed Central

    Sottnik, Joseph L; Campbell, Brittany; Mehra, Rohit; Behbahani-Nejad, Omid; Hall, Christopher L.; Keller, Evan T.

    2016-01-01

    Osteosarcoma (OSA) is the most common primary bone tumor in humans. However, the cell of origin of OSA is not clearly defined although there is evidence that osteoblasts may serve as OSA progenitors. The role of osteocytes, terminally differentiated osteoblasts, as OSA progenitors has yet to be described. Analysis of patient cDNA from publicly available microarray data revealed that patients with OSA have increased expression of dentin matrix phosphoprotein 1 (DMP1), a marker of osteocytes. Analysis of multiple murine, human, and canine OSA cell lines revealed DMP1 expression. To test the tumorigenic potential of osteocytes, MLO-Y4, an SV-40 immortalized murine osteocyte cell line, was injected into subcutaneous and orthotopic (intratibial) sites of mice. Tumor growth occurred in both locations. Orthotopic MLO-Y4 tumors produced mixed osteoblastic/osteolytic radiographic lesions; a hallmark of OSA. Together, these data demonstrate for the first time that osteocytes can serve as OSA progenitors. PMID:24700678

  10. Osteocytes serve as a progenitor cell of osteosarcoma.

    PubMed

    Sottnik, Joseph L; Campbell, Brittany; Mehra, Rohit; Behbahani-Nejad, Omid; Hall, Christopher L; Keller, Evan T

    2014-08-01

    Osteosarcoma (OSA) is the most common primary bone tumor in humans. However, the cell of origin of OSA is not clearly defined although there is evidence that osteoblasts may serve as OSA progenitors. The role of osteocytes, terminally differentiated osteoblasts, as OSA progenitors has yet to be described. Analysis of patient cDNA from publicly available microarray data revealed that patients with OSA have increased expression of dentin matrix phosphoprotein 1 (DMP1), a marker of osteocytes. Analysis of multiple murine, human, and canine OSA cell lines revealed DMP1 expression. To test the tumorigenic potential of osteocytes, MLO-Y4, a SV-40 immortalized murine osteocyte cell line, was injected into subcutaneous and orthotopic (intratibial) sites of mice. Tumor growth occurred in both locations. Orthotopic MLO-Y4 tumors produced mixed osteoblastic/osteolytic radiographic lesions; a hallmark of OSA. Together, these data demonstrate for the first time that osteocytes can serve as OSA progenitors. PMID:24700678

  11. MicroRNA-21 Increases Proliferation and Cisplatin Sensitivity of Osteosarcoma-Derived Cells

    PubMed Central

    Vanas, Vanita; Haigl, Barbara; Stockhammer, Verena; Sutterlüty-Fall, Hedwig

    2016-01-01

    Osteosarcoma is the most common primary bone tumor and poor prognosis for osteosarcoma patients is mainly due to chemotherapy resistance. MicroRNAs are important to maintain pathophysiological mechanisms of cancer and influence cell sensitivity to chemotherapy. In this study, we tested the functions of microRNA-21 for malignant features as well as for drug resistance of osteosarcoma. We used Northern blot to measure microRNA-21 levels in osteosarcoma-derived cell lines. MicroRNA-21 activity was modulated by either expressing a sponge to decrease its activity in an osteosarcoma-derived cell line expressing high levels of microRNA-21 or by introducing pri-microRNA-21 in a cell line with low endogenous levels. Cell migration was determined in a scratch assay and cell proliferation was measured by performing growth curve analysis. Sensitivity of the cells towards chemotherapeutics was investigated by performing cell viability assays and calculating the IC50 values. While cell migration was unaffected by modulated microRNA-21 levels, microRNA-21 inhibition slowed proliferation and exogenously expressed microRNA-21 promoted this process. Modulated microRNA-21 activity failed to effect sensitivity of osteosarcoma-derived cell lines to doxorubicin or methotrexate. Contrarily, reduction of microRNA-21 activity resulted in enhanced resistance towards cisplatin while ectopic expression of microRNA-21 showed the opposite effect. Increased microRNA-21 levels repressed the expression of Sprouty2 and ectopic expression of Sprouty2 was able to largely rescue the observed effects of microRNA-21 in osteosarcoma. In summary, our data indicate that in osteosarcoma microRNA-21 expression is an important component for regulation of cell proliferation and for determining sensitivity to cisplatin. PMID:27513462

  12. MicroRNA-21 Increases Proliferation and Cisplatin Sensitivity of Osteosarcoma-Derived Cells.

    PubMed

    Vanas, Vanita; Haigl, Barbara; Stockhammer, Verena; Sutterlüty-Fall, Hedwig

    2016-01-01

    Osteosarcoma is the most common primary bone tumor and poor prognosis for osteosarcoma patients is mainly due to chemotherapy resistance. MicroRNAs are important to maintain pathophysiological mechanisms of cancer and influence cell sensitivity to chemotherapy. In this study, we tested the functions of microRNA-21 for malignant features as well as for drug resistance of osteosarcoma. We used Northern blot to measure microRNA-21 levels in osteosarcoma-derived cell lines. MicroRNA-21 activity was modulated by either expressing a sponge to decrease its activity in an osteosarcoma-derived cell line expressing high levels of microRNA-21 or by introducing pri-microRNA-21 in a cell line with low endogenous levels. Cell migration was determined in a scratch assay and cell proliferation was measured by performing growth curve analysis. Sensitivity of the cells towards chemotherapeutics was investigated by performing cell viability assays and calculating the IC50 values. While cell migration was unaffected by modulated microRNA-21 levels, microRNA-21 inhibition slowed proliferation and exogenously expressed microRNA-21 promoted this process. Modulated microRNA-21 activity failed to effect sensitivity of osteosarcoma-derived cell lines to doxorubicin or methotrexate. Contrarily, reduction of microRNA-21 activity resulted in enhanced resistance towards cisplatin while ectopic expression of microRNA-21 showed the opposite effect. Increased microRNA-21 levels repressed the expression of Sprouty2 and ectopic expression of Sprouty2 was able to largely rescue the observed effects of microRNA-21 in osteosarcoma. In summary, our data indicate that in osteosarcoma microRNA-21 expression is an important component for regulation of cell proliferation and for determining sensitivity to cisplatin. PMID:27513462

  13. Gene expression profiling analysis of osteosarcoma cell lines

    PubMed Central

    SUN, LU; LI, JIE; YAN, BING

    2015-01-01

    Osteosarcoma (OS) is the most common type of primary bone malignancy and has a poor prognosis. To investigate the mechanisms of osteosarcoma, the present analyzed the GSE28424 microarray. GSE28424 was downloaded from the Gene Expression Omnibus, and included a collective of 19 OS cell lines and four normal bone cell lines, which were used as controls. Subsequently, the differentially expressed genes (DEGs) were screened using the Limma package in Bioconductor. Gene Ontology (GO) and pathway enrichment analysis of the DEGs was performed using the Database for Annotation, Visualization and Integrated Discovery, interactions between the proteins encoded by the DEGs were identified using STRING, and the protein-protein interaction (PPI) network was visualized using Cytoscape. In addition, modular analysis of the PPI network was performed using the Clique Percolation Method (CPM) in CFinder. A total of 1,170 DEGs were screened, including 530 upreguated and 640 downregulated genes. The enriched functions included organelle fission, immune response and response to wounding. In addition, RPL8 was observed to be involved with the ribosomal pathway in module A of the PPI network of the DEGs. PLCG1, SYK and PLCG2 were also involved in the B-cell receptor signaling pathway in module B and the Fc-epsilon RI signaling pathway in module C. In addition, AURKA (degree=39), MAD2L1 (degree=38), CDCA8 (degree=38), BUB1 (degree=37) and MELK (degree=37) exhibited higher degrees of connectivity in module F. The results of the present study suggested that the RPL8, PLCG1, PLCG2, SYK, MAD2L1, AURKA, CDCA8, BUB1 and MELK genes may be involved in OS. PMID:26096802

  14. Gene expression profiling analysis of osteosarcoma cell lines.

    PubMed

    Sun, Lu; Li, Jie; Yan, Bing

    2015-09-01

    Osteosarcoma (OS) is the most common type of primary bone malignancy and has a poor prognosis. To investigate the mechanisms of osteosarcoma, the present analyzed the GSE28424 microarray. GSE28424 was downloaded from the Gene Expression Omnibus, and included a collective of 19 OS cell lines and four normal bone cell lines, which were used as controls. Subsequently, the differentially expressed genes (DEGs) were screened using the Limma package in Bioconductor. Gene Ontology (GO) and pathway enrichment analysis of the DEGs was performed using the Database for Annotation, Visualization and Integrated Discovery, interactions between the proteins encoded by the DEGs were identified using STRING, and the protein‑protein interaction (PPI) network was visualized using Cytoscape. In addition, modular analysis of the PPI network was performed using the Clique Percolation Method (CPM) in CFinder. A total of 1,170 DEGs were screened, including 530 upreguated and 640 downregulated genes. The enriched functions included organelle fission, immune response and response to wounding. In addition, RPL8 was observed to be involved with the ribosomal pathway in module A of the PPI network of the DEGs. PLCG1, SYK and PLCG2 were also involved in the B‑cell receptor signaling pathway in module B and the Fc‑epsilon RI signaling pathway in module C. In addition, AURKA (degree=39), MAD2L1 (degree=38), CDCA8 (degree=38), BUB1 (degree=37) and MELK (degree=37) exhibited higher degrees of connectivity in module F. The results of the present study suggested that the RPL8, PLCG1, PLCG2, SYK, MAD2L1, AURKA, CDCA8, BUB1 and MELK genes may be involved in OS. PMID:26096802

  15. Identification of CBX3 and ABCA5 as Putative Biomarkers for Tumor Stem Cells in Osteosarcoma

    PubMed Central

    Saini, Vaibhav; Hose, Curtis D.; Monks, Anne; Nagashima, Kunio; Han, Bingnan; Newton, Dianne L.; Millione, Angelena; Shah, Jalpa; Hollingshead, Melinda G.; Hite, Karen M.; Burkett, Mark W.; Delosh, Rene M.; Silvers, Thomas E.; Scudiero, Dominic A.; Shoemaker, Robert H.

    2012-01-01

    Recently, there has been renewed interest in the role of tumor stem cells (TSCs) in tumorigenesis, chemoresistance, and relapse of malignant tumors including osteosarcoma. The potential exists to improve osteosarcoma treatment through characterization of TSCs and identification of therapeutic targets. Using transcriptome, proteome, immunophenotyping for cell-surface markers, and bioinformatic analyses, heterogeneous expression of previously reported TSC or osteosarcoma markers, such as CD133, nestin, POU5F1 (OCT3/4), NANOG, SOX2, and aldehyde dehydrogenase, among others, was observed in vitro. However, consistently significantly lower CD326, CD24, CD44, and higher ABCG2 expression in TSC-enriched as compared with un-enriched osteosarcoma cultures was observed. In addition, consistently higher CBX3 expression in TSC-enriched osteosarcoma cultures was identified. ABCA5 was identified as a putative biomarker of TSCs and/or osteosarcoma. Lastly, in a high-throughput screen we identified epigenetic (5-azacytidine), anti-microtubule (vincristine), and anti-telomerase (3,11-difluoro-6,8,13-trimethyl- 8H-quino [4,3,2-kl] acridinium methosulfate; RHPS4)-targeted therapeutic agents as candidates for TSC ablation in osteosarcoma. PMID:22870217

  16. Runx2, p53, and pRB status as diagnostic parameters for deregulation of osteoblast growth and differentiation in a new pre-chemotherapeutic osteosarcoma cell line (OS1).

    PubMed

    Pereira, Barry P; Zhou, Yefang; Gupta, Anurag; Leong, David T; Aung, Khin Zarchi; Ling, Ling; Pho, Robert W H; Galindo, Mario; Salto-Tellez, Manuel; Stein, Gary S; Cool, Simon M; van Wijnen, Andre J; Nathan, Saminathan S

    2009-12-01

    Osteosarcomas are the most prevalent primary bone tumors found in pediatric patients. To understand their molecular etiology, cell culture models are used to define disease mechanisms under controlled conditions. Many osteosarcoma cell lines (e.g., SAOS-2, U2OS, MG63) are derived from Caucasian patients. However, patients exhibit individual and ethnic differences in their responsiveness to irradiation and chemotherapy. This motivated the establishment of osteosarcoma cell lines (OS1, OS2, OS3) from three ethnically Chinese patients. OS1 cells, derived from a pre-chemotherapeutic tumor in the femur of a 6-year-old female, were examined for molecular markers characteristic for osteoblasts, stem cells, and cell cycle control by immunohistochemistry, reverse transcriptase-PCR, Western blotting and flow cytometry. OS1 have aberrant G-banded karyotypes, possibly reflecting chromosomal abnormalities related to p53 deficiency. OS1 had ossification profiles similar to human fetal osteoblasts rather than SAOS-2 which ossifies ab initio (P < 0.05). Absence of p53 correlates with increased Runx2 expression, while the slow proliferation of OS1 cells is perhaps attenuated by pRB retention. OS1 express mesenchymal stem cell markers (CD44, CD105) and differ in relative expression of CD29, CD63, and CD71 to SAOS-2. (P < 0.05). Cell cycle synchronization with nocodazole did not affect Runx2 and CDK1 levels but decreased cyclin-E and increased cyclin-A (P < 0.05). Xenotransplantion of OS1 in SCID mice yields spontaneous tumors that were larger and grew faster than SAOS-2 transplants. Hence, OS1 is a new osteosarcoma cell culture model derived from a pre-chemotherapeutic ethnic Chinese patient, for mechanistic studies and development of therapeutic strategies to counteract metastasis and deregulation of mesenchymal development. PMID:19746444

  17. MEK inhibition induces apoptosis in osteosarcoma cells with constitutive ERK1/2 phosphorylation.

    PubMed

    Baranski, Zuzanna; Booij, Tijmen H; Kuijjer, Marieke L; de Jong, Yvonne; Cleton-Jansen, Anne-Marie; Price, Leo S; van de Water, Bob; Bovée, Judith V M G; Hogendoorn, Pancras C W; Danen, Erik H J

    2015-11-01

    Conventional high-grade osteosarcoma is the most common primary bone cancer with relatively high incidence in young people. Recurrent and metastatic tumors are difficult to treat. We performed a kinase inhibitor screen in two osteosarcoma cell lines, which identified MEK1/2 inhibitors. These inhibitors were further validated in a panel of six osteosarcoma cell lines. Western blot analysis was performed to assess ERK activity and efficacy of MEK inhibition. A 3D culture system was used to validate results from 2D monolayer cultures. Gene expression analysis was performed to identify differentially expressed gene signatures in sensitive and resistant cell lines. Activation of the AKT signaling network was explored using Western blot and pharmacological inhibition. In the screen, Trametinib, AZD8330 and TAK-733 decreased cell viability by more than 50%. Validation in six osteosarcoma cell lines identified three cell lines as resistant and three as sensitive to the inhibitors. Western blot analysis of ERK activity revealed that sensitive lines had high constitutive ERK activity. Treatment with the three MEK inhibitors in a 3D culture system validated efficacy in inhibition of osteosarcoma viability. MEK1/2 inhibition represents a candidate treatment strategy for osteosarcomas displaying high MEK activity as determined by ERK phosphorylation status. PMID:26807203

  18. Morphological and Immunohistochemical Characterization of Canine Osteosarcoma Spheroid Cell Cultures.

    PubMed

    Gebhard, C; Gabriel, C; Walter, I

    2016-06-01

    Spheroid cell culture emerges as powerful in vitro tool for experimental tumour research. In this study, we established a scaffold-free three-dimensional spheroid system built from canine osteosarcoma (OS) cells (D17). Spheroids (7, 14 and 19 days of cultivation) and monolayer cultures (2 and 7 days of cultivation) were evaluated and compared on light and electron microscopy. Monolayer and spheroid cultures were tested for vimentin, cytokeratin, alkaline phosphatase, osteocalcin and collagen I by means of immunohistochemistry. The spheroid cell culture exhibited a distinct network of collagen I in particular after 19-day cultivation, whereas in monolayer cultures, collagen I was arranged as a lamellar basal structure. Necrotic centres of large spheroids, as observed in 14- and 19-day cultures, were characterized by significant amounts of osteocalcin. Proliferative activity as determined by Ki-67 immunoreactivity showed an even distribution in two-dimensional cultures. In spheroids, proliferation was predominating in the peripheral areas. Metastasis-associated markers ezrin and S100A4 were shown to be continuously expressed in monolayer and spheroid cultures. We conclude that the scaffold-free spheroid system from canine OS cells has the ability to mimic the architecture of the in vivo tumour, in particular cell-cell and cell-matrix interactions. PMID:26287450

  19. Establishment and characterization of a new highly metastatic human osteosarcoma cell line derived from Saos2

    PubMed Central

    Du, Lin; Fan, Qiming; Tu, Bing; Yan, Wei; Tang, Tingting

    2014-01-01

    Osteosarcoma is the most common primary malignancy of bone in adolescents and young adults. There is a shortage of tumorigenic and highly metastatic human osteosarcoma cell lines that can be used for metastasis study. Here we establish and characterize a highly metastatic human osteosarcoma cell line that is derived from Saos2 cell line based on bioluminescence. The occasional pulmonary metastatic cells developed from Saos2 were isolated, harvested, characterized and named Saos2-l. The parental Saos2 and Saos2-l cells were further characterized both in vitro and in vivo. Results showed that Saos2-l cells demonstrated increased cell adhesion, migration and invasion compared to the parental Saos2 cells. Conversely, Saos2-l cells grew at a slightly slower rate than that of the parental cells. When injected into nude mice, Saos2-l cells had a greater increase in developing pulmonary metastases compared to the parental Saos2 cells. Further transcriptional profiling analysis revealed that some gene expression were up-regulated or down-regulated in the highly metastatic Saos2-l cells, indicating possible influencing factors of metastasis. Thus, we have established and characterized a highly metastatic human osteosarcoma cell line that should serve as a valuable tool for future investigations on the pathogenesis, metastasis and potential treatments of human osteosarcoma. PMID:25031706

  20. Low-Level Light Therapy Potentiates NPe6-mediated Photodynamic Therapy in a Human Osteosarcoma Cell Line via Increased ATP

    PubMed Central

    Tsai, Shang-Ru; Yin, Rui; Huang, Ying-Ying; Sheu, Bor-Ching; Lee, Si-Chen; Hamblin, Michael R.

    2015-01-01

    Background Low-Level Light Therapy (LLLT) is used to stimulate healing, reduce pain and inflammation, and preserve tissue from dying. LLLT has been shown to protect cells in culture from dying after various cytotoxic insults, and LLLT is known to increase the cellular ATP content. Previous studies have demonstrated that maintaining a sufficiently high ATP level is necessary for the efficient induction and execution of apoptosis steps after photodynamic therapy (PDT). Methods We asked whether LLLT would protect cells from cytotoxicity due to PDT, or conversely whether LLLT would enhance the efficacy of PDT mediated by mono-L-aspartyl chlorin(e6) (NPe6). Increased ATP could lead to enhanced cell uptake of NPe6 by the energy dependent process of endocytosis, and also to more efficient apoptosis. In this study, human osteosarcoma cell line MG-63 was subjected to 1.5 J/cm2 of 810 nm near infrared radiation (NIR) followed by addition of 10 μM NPe6 and after 2 h incubation by 1.5 J/cm2 of 652 nm red light for PDT. Results PDT combined with LLLT led to higher cell death and increased intracellular reactive oxygen species compared to PDT alone. The uptake of NPe6 was moderately increased by LLLT, and cellular ATP was increased. The mitochondrial respiratory chain inhibitor antimycin A abrogated the LLLT-induced increase in cytotoxicity. Conclusions Taken together, these results demonstrate that LLLT potentiates NPe6-mediated PDT via increased ATP synthesis and is a potentially promising strategy that could be applied in clinical PDT. PMID:25462575

  1. Oncogenic roles of carbonic anhydrase 8 in human osteosarcoma cells.

    PubMed

    Wang, Tze-Kai; Lin, Yu-Ming; Lo, Che-Min; Tang, Chih-Hsin; Teng, Chieh-Lin Jerry; Chao, Wei-Ting; Wu, Min Huan; Liu, Chin-San; Hsieh, Mingli

    2016-06-01

    Carbonic anhydrase 8 (CA8), a member of the carbonic anhydrase family, is one of the three isozymes that do not catalyze the reversible hydration of carbon dioxide due to the lack of one important histidine. In the present study, we observed increased expression of CA8 in more aggressive types of human osteosarcoma (OS) cells and found that CA8 expression is correlated with disease stages, such that more intense expression occurs in the disease late stage. We also demonstrated that overexpression of CA8 in human OS (HOS) cells significantly increased cell proliferation both in vitro and in vivo. Downregulated CA8 sensitized cells to apoptotic stress induced by staurosporine and cisplatin, suggesting a specific role of CA8 to protect cells from stresses. In addition, downregulation of CA8 in HOS cells reduced cell invasion and colony formation ability in soft agar and further decreased matrix metalloproteinase 9 and focal adhesion kinase expression, indicating that CA8 might facilitate cancer cell invasion via the activation of FAK-MMP9 signaling. Interestingly, HOS cells with CA8 knockdown showed a significant decrease in glycolytic activity and cell death under glucose withdrawal, further indicating that CA8 may be involved in regulating aerobic glycolysis and enhancing cell viability. Knockdown of CA8 significantly decreased phosphorylated Akt expression suggesting that the oncogenic role of CA8 may be mediated by the regulation of Akt activation through p-Akt induction. Importantly, the inhibition of glycolysis by 2-deoxyglucose sensitized CA8 HOS-CA8-myc cells to cisplatin treatment under low glucose condition, highlighting a new therapeutic option for OS cancer. PMID:26711783

  2. Long non-coding RNA tumor suppressor candidate 7 functions as a tumor suppressor and inhibits proliferation in osteosarcoma.

    PubMed

    Cong, Menglin; Li, Jianmin; Jing, Rui; Li, Zhenzhong

    2016-07-01

    Osteosarcoma is the most common malignant tumor of bone. Recent studies have proven long non-coding RNAs (lncRNAs) play important roles in the tumorigenesis and progression of cancer. However, few lncRNAs have been investigated in osteosarcoma. Here, we reported a novel lncRNA, tumor suppressor candidate 7 (TUSC7), was significantly downregulated in osteosarcoma tissues compared with paired non-tumor tissues and low expression of TUSC7 indicated poor survival (HR = 0.313, 95 % confidence interval (CI) 0.092-0.867) of osteosarcoma patients. Further analysis revealed that loss copy number of TUSC7 was correlated with low expression of TUSC7, and additionally, loss of TUSC7 copy number also indicated poor prognosis (HR = 3.994, 95 % CI 1.147-13.91) of osteosarcoma patients. Two osteosarcoma cell lines, HOS and MG63, were utilized to investigate biological function of TUSC7. Cell counting kit 8 (CCK-8) assay revealed that after silence of TUSC7, cell proliferation ability increased and the colony formation ability also increased. Further results showed that cell cycle was not affected by treatment of si-TUSC7, while the percentage of apoptotic cells decreased. Western blot showed that after silence of TUSC7, the proapoptotic Bcl2 expression was downregulated. Finally, we established xenograft tumor models in nude mice with MG63 cells. Compared with negative control group, silence of TUSC7 significantly promoted tumor growth in vivo. Thus, we demonstrated that TUSC7 could be a potential tumor suppressor in osteosarcoma. PMID:26781978

  3. Suppression of liver receptor homolog-1 by microRNA-451 represses the proliferation of osteosarcoma cells

    SciTech Connect

    Li, Zhiyong; Wu, Shuwen; Lv, Shouzheng; Wang, Huili; Wang, Yong; Guo, Qiang

    2015-06-05

    Liver receptor homolog-1 (LRH-1) plays an important role in the onset and progression of many cancer types. However, the role of LRH-1 in osteosarcoma has not been well investigated. In this study, the critical role of LRH-1 in osteosarcoma cells was described. Quantitative polymerase chain reaction and Western blot analysis results revealed that LRH-1 was highly overexpressed in osteosarcoma cells. LRH-1 was knocked down by small interfering RNA (siRNA), and this phenomenon significantly inhibited osteosarcoma cell proliferation. Bioinformatics analysis results showed that LRH-1 contained putative binding sites of microRNA-451 (miR-451); this result was further validated through a dual-luciferase activity reporter assay. miR-451 was overexpressed in osteosarcoma cells through transfection of miR-451 mimics; miR-451 overexpression then significantly inhibited LRH-1 expression and cell proliferation. The loss of LRH-1 by siRNA or miR-451 mimics significantly impaired Wnt/β-catenin activity, leading to G0/G1 cell cycle arrest. Results showed that LRH-1 is implicated in osteosarcoma. Therefore, miR-451-induced suppression of LRH-1 can be a novel therapy to treat osteosarcoma. - Highlights: • LRH-1 was highly overexpressed in osteosarcoma cells. • Knockdown of LRH-1 inhibited osteosarcoma cell proliferation. • miR-451 directly targeted and regulated LRH-1 expression. • Overexpression of miR-451 suppressed Wnt activity.

  4. Impaired cell cycle regulation of the osteoblast-related heterodimeric transcription factor Runx2-Cbfbeta in osteosarcoma cells.

    PubMed

    San Martin, Inga A; Varela, Nelson; Gaete, Marcia; Villegas, Karina; Osorio, Mariana; Tapia, Julio C; Antonelli, Marcelo; Mancilla, Edna E; Pereira, Barry P; Nathan, Saminathan S; Lian, Jane B; Stein, Janet L; Stein, Gary S; van Wijnen, Andre J; Galindo, Mario

    2009-12-01

    Bone formation and osteoblast differentiation require the functional expression of the Runx2/Cbfbeta heterodimeric transcription factor complex. Runx2 is also a suppressor of proliferation in osteoblasts by attenuating cell cycle progression in G(1). Runx2 levels are modulated during the cell cycle, which are maximal in G(1) and minimal beyond the G(1)/S phase transition (S, G(2), and M phases). It is not known whether Cbfbeta gene expression is cell cycle controlled in preosteoblasts nor how Runx2 or Cbfbeta are regulated during the cell cycle in bone cancer cells. We investigated Runx2 and Cbfbeta gene expression during cell cycle progression in MC3T3-E1 osteoblasts, as well as ROS17/2.8 and SaOS-2 osteosarcoma cells. Runx2 protein levels are reduced as expected in MC3T3-E1 cells arrested in late G(1) (by mimosine) or M phase (by nocodazole), but not in cell cycle arrested osteosarcoma cells. Cbfbeta protein levels are cell cycle independent in both osteoblasts and osteosarcoma cells. In synchronized MC3T3-E1 osteoblasts progressing from late G1 or mitosis, Runx2 levels but not Cbfbeta levels are cell cycle regulated. However, both factors are constitutively elevated throughout the cell cycle in osteosarcoma cells. Proteasome inhibition by MG132 stabilizes Runx2 protein levels in late G(1) and S in MC3T3-E1 cells, but not in ROS17/2.8 and SaOS-2 osteosarcoma cells. Thus, proteasomal degradation of Runx2 is deregulated in osteosarcoma cells. We propose that cell cycle control of Runx2 gene expression is impaired in osteosarcomas and that this deregulation may contribute to the pathogenesis of osteosarcoma. PMID:19739101

  5. Histone deacetylase inhibitor sodium butyrate suppresses proliferation and promotes apoptosis in osteosarcoma cells by regulation of the MDM2–p53 signaling

    PubMed Central

    Xie, Chuhai; Wu, Boyi; Chen, Binwei; Shi, Qunwei; Guo, Jianhong; Fan, Ziwen; Huang, Yan

    2016-01-01

    Histone deacetylase inhibitors have been reported to induce tumor cell growth arrest, differentiation, and apoptosis. This study aimed to investigate the effects of one histone deacetylase inhibitor – sodium butyrate (SB) – on osteosarcoma (OS) cell proliferation and apoptosis and also the molecular mechanisms by which SB exerts regulatory effects on OS cells. U2OS and MG63 cells were treated with SB at various concentrations. Then, cell proliferation and apoptosis were determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide and flow cytometry assays, respectively; the expression of Ki67, Bax, Bcl-2, MDM2, and p53 proteins was determined by using Western blot assay. The results showed that SB suppressed proliferation in a concentration-dependent manner and promoted apoptosis of OS cells. In addition, SB enhanced p53 expression and decreased MDM2 expression, indicating that SB can regulate MDM2–p53 feedback loop. p53 inhibited proliferation and promoted apoptosis, whereas MDM2 promoted proliferation and suppressed apoptosis, which indicated that functional effect of SB on OS cell lines at least in part depended on the MDM2–p53 signaling. We also explored the effect of SB on OS cells in vivo and found that SB suppressed the growth of OS cells with no noticeable effect on activity and body weight of mice in vivo. These findings will offer new clues for OS development and progression and offer SB as a potent targeted agent for OS treatment. PMID:27445491

  6. Histone deacetylase inhibitor sodium butyrate suppresses proliferation and promotes apoptosis in osteosarcoma cells by regulation of the MDM2-p53 signaling.

    PubMed

    Xie, Chuhai; Wu, Boyi; Chen, Binwei; Shi, Qunwei; Guo, Jianhong; Fan, Ziwen; Huang, Yan

    2016-01-01

    Histone deacetylase inhibitors have been reported to induce tumor cell growth arrest, differentiation, and apoptosis. This study aimed to investigate the effects of one histone deacetylase inhibitor - sodium butyrate (SB) - on osteosarcoma (OS) cell proliferation and apoptosis and also the molecular mechanisms by which SB exerts regulatory effects on OS cells. U2OS and MG63 cells were treated with SB at various concentrations. Then, cell proliferation and apoptosis were determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide and flow cytometry assays, respectively; the expression of Ki67, Bax, Bcl-2, MDM2, and p53 proteins was determined by using Western blot assay. The results showed that SB suppressed proliferation in a concentration-dependent manner and promoted apoptosis of OS cells. In addition, SB enhanced p53 expression and decreased MDM2 expression, indicating that SB can regulate MDM2-p53 feedback loop. p53 inhibited proliferation and promoted apoptosis, whereas MDM2 promoted proliferation and suppressed apoptosis, which indicated that functional effect of SB on OS cell lines at least in part depended on the MDM2-p53 signaling. We also explored the effect of SB on OS cells in vivo and found that SB suppressed the growth of OS cells with no noticeable effect on activity and body weight of mice in vivo. These findings will offer new clues for OS development and progression and offer SB as a potent targeted agent for OS treatment. PMID:27445491

  7. Anemone altaica Induces Apoptosis in Human Osteosarcoma Cells.

    PubMed

    Chang, I-Chang; Chiang, Tsay-I; Lo, Chun; Lai, Yi-Hua; Yue, Chia-Herng; Liu, Jer-Yuh; Hsu, Li-Sung; Lee, Chia-Jen

    2015-01-01

    In the past decade, no significant improvement has been made in chemotherapy for osteosarcoma (OS). To develop improved agents against OS, we screened 70 species of medicinal plants and treated two human OS cell lines with different agent concentrations. We then examined cell viability using the MTT assay. Results showed that a candidate plant, particularly the rhizomes of Anemone altaica Fisch. ex C. A. Mey aqueous extract (AAE), suppressed the viability of HOS and U2OS cells in a concentration-dependent manner. Flow cytometry analysis revealed that AAE significantly increased the amount of cell shrinkage (Sub-G1 fragments) in HOS and U2OS cells. Moreover, AAE increased cytosolic cytochrome c and Bax, but decreased Bcl-2. The amount of cleaved caspase-3 and poly-(ADP-ribose) polymerase-1 (PARP-1) were significantly increased. AAE suppressed the growth of HOS and U2OS through the intrinsic apoptotic pathway. Data suggest that AAE is cytotoxic to HOS and U2OS cells and has no significant influence on human osteoblast hFOB cells. The high mRNA levels of apoptosis-related factors (PPP1R15A, SQSTM1, HSPA1B, and DDIT4) and cellular proliferation markers (SKA2 and BUB1B) were significantly altered by the AAE treatment of HOS and U2OS cells. Results show that the anticancer activity of AAE could up-regulate the expression of a cluster of genes, especially those in the apoptosis-related factor family and caspase family. Thus, AAE has great potential as a useful therapeutic drug for human OS. PMID:26224029

  8. Genomic instability and telomere fusion of canine osteosarcoma cells.

    PubMed

    Maeda, Junko; Yurkon, Charles R; Fujisawa, Hiroshi; Kaneko, Masami; Genet, Stefan C; Roybal, Erica J; Rota, Garrett W; Saffer, Ethan R; Rose, Barbara J; Hanneman, William H; Thamm, Douglas H; Kato, Takamitsu A

    2012-01-01

    Canine osteosarcoma (OSA) is known to present with highly variable and chaotic karyotypes, including hypodiploidy, hyperdiploidy, and increased numbers of metacentric chromosomes. The spectrum of genomic instabilities in canine OSA has significantly augmented the difficulty in clearly defining the biological and clinical significance of the observed cytogenetic abnormalities. In this study, eight canine OSA cell lines were used to investigate telomere fusions by fluorescence in situ hybridization (FISH) using a peptide nucleotide acid probe. We characterized each cell line by classical cytogenetic studies and cellular phenotypes including telomere associated factors and then evaluated correlations from this data. All eight canine OSA cell lines displayed increased abnormal metacentric chromosomes and exhibited numerous telomere fusions and interstitial telomeric signals. Also, as evidence of unstable telomeres, colocalization of γ-H2AX and telomere signals in interphase cells was observed. Each cell line was characterized by a combination of data representing cellular doubling time, DNA content, chromosome number, metacentric chromosome frequency, telomere signal level, cellular radiosensitivity, and DNA-PKcs protein expression level. We have also studied primary cultures from 10 spontaneous canine OSAs. Based on the observation of telomere aberrations in those primary cell cultures, we are reasonably certain that our observations in cell lines are not an artifact of prolonged culture. A correlation between telomere fusions and the other characteristics analyzed in our study could not be identified. However, it is important to note that all of the canine OSA samples exhibiting telomere fusion utilized in our study were telomerase positive. Pending further research regarding telomerase negative canine OSA cell lines, our findings may suggest telomere fusions can potentially serve as a novel marker for canine OSA. PMID:22916246

  9. Knockdown of TRAF4 expression suppresses osteosarcoma cell growth in vitro and in vivo.

    PubMed

    Yao, Weitao; Wang, Xin; Cai, Qiqing; Gao, Songtao; Wang, Jiaqiang; Zhang, Peng

    2014-12-01

    Tumor necrosis factor (TNF) receptor-associated factor 4 (TRAF4) is an adapter molecule that is overexpressed in certain cancers. TRAF4 is overexpressed in osteosarcoma tissues and osteosarcoma cells. Using the technique of RNA interference, the expression of TRAF4 in the human osteosarcoma Saos-2 cell line was shown to be downregulated. The proliferation, cell cycle arrest and apoptosis ability of Saos‑2 cells were examined, as was tumor development in a xenograft mouse model. The results showed that the TRAF4 knockdown exerts inhibitory effects on the proliferation ability of Saos-2 cells and tumor development in a xenograft mouse model. Simultaneously, it was found that TRAF4 knockdown led to cell cycle arrest in the G1 phase and promoted Saos-2 cell apoptosis. Following TNF-α treatment, the expression of nuclear factor κB was significantly reduced in the TRAF4‑small interfering RNA group. These results indicate that TRAF4 regulated osteosarcoma cell growth in vitro and in vivo, and offers a candidate molecular target for osteosarcoma prevention and therapy. PMID:25270078

  10. MicroRNA-200b acts as a tumor suppressor in osteosarcoma via targeting ZEB1

    PubMed Central

    Li, Yusheng; Zeng, Chao; Tu, Min; Jiang, Wei; Dai, Zixun; Hu, Yuling; Deng, Zhenhan; Xiao, Wenfeng

    2016-01-01

    Osteosarcoma is the most common type of cancer that develops in bone, mainly arising from the metaphysis of the long bones. MicroRNA (miR)-200b has been found to generally act as a tumor suppressor in multiple types of human cancers. However, the detailed role of miR-200b in osteosarcoma still remains to be fully understood. This study aimed to investigate the exact role of miR-200b in the progression of osteosarcoma and the underlying mechanism. Real-time reverse transcription-polymerase chain reaction data showed that miR-200b was significantly downregulated in osteosarcoma tissues compared to their matched adjacent nontumor tissues. Low miR-200b level was associated with the advanced clinical stage and positive distant metastasis. Besides, it was also downregulated in osteosarcoma cell lines (U2OS, Saos2, HOS, and MG63) compared to normal osteoblast cell line NHOst. In vitro study showed that restoration of miR-200b led to a significant decrease in proliferation, migration, and invasion of osteosarcoma cells. Moreover, ZEB1 was identified as a target gene of miR-200b, and its expression levels were negatively mediated by miR-200b in osteosarcoma cells. In addition, ZEB1 was significantly upregulated in osteosarcoma cells compared to the normal osteoblast cell line NHOst, and inhibition of ZEB1 expression also suppressed the proliferation, migration, and invasion in osteosarcoma cells. Finally, we showed that ZEB1 was frequently upregulated in osteosarcoma tissues compared to their matched adjacent normal tissues, and its expression was reversely correlated to the miR-200b levels in osteosarcoma tissues. Based on these findings, our study suggests that miR-200b inhibits the proliferation, migration, and invasion of osteosarcoma cells, probably via the inhibition of ZEB1 expression. Therefore, miR-200b/ZEB1 may become a potential target for the treatment of osteosarcoma. PMID:27307751

  11. Hypoxia-induced resistance to cisplatin-mediated apoptosis in osteosarcoma cells is reversed by gambogic acid independently of HIF-1α.

    PubMed

    Zhao, Wei; Xia, Shi-Qi; Zhuang, Jin-Peng; Zhang, Zhi-Peng; You, Chang-Cheng; Yan, Jing-Long; Xu, Gong-Ping

    2016-09-01

    In vitro evidence of hypoxia-induced resistance to cisplatin (CDDP)-mediated apoptosis exists in human osteosarcoma (OS). Gambogic acid (GA) is a promising chemotherapeutic compound that could increase the chemotherapeutic effectiveness of CDDP in human OS cells by inducing cell cycle arrest and promoting apoptosis. This study examined whether GA could overcome OS cell resistance to CDDP. Hypoxia significantly reduced levels of CDDP-induced apoptosis in the OS cell lines MG63 and HOS. However, combined treatment with GA and CDDP revealed a strong synergistic action between these drugs, and higher protein levels of the apoptosis-related factor Fas, cleaved caspase-8 and cleaved caspase-3 and lower expression of hypoxia-inducible factor (HIF)-1α are detected in both cell lines. Meanwhile, drug resistance was not reversed by exposure to the HIF-1α inhibitor 2-methoxyestradiol. These findings strongly suggest that hypoxia-induced resistance to CDDP is reversed by GA in OS cells independently of HIF-1α. Furthermore, in vivo studies using xenograft mouse models revealed that combination therapy with CDDP and GA exerted increased antitumor effects by inducing apoptosis. Taken together, our results demonstrate that GA may be a new potent therapeutic agent useful for targeting human OS cells. PMID:27473145

  12. SerpinE2 promotes multiple cell proliferation and drug resistance in osteosarcoma.

    PubMed

    Mao, Minzhi; Wang, Wanchun

    2016-07-01

    SerpinE2 is a member of the Serpins family, which could inhibit serine protease and promote tumor progression, particularly in tumor metastasis. However, at present, its role in the progression of osteosarcoma has not been determined. The present study analyzed the expression profiles of SerpinE2 in cancer tissues, including tissues from osteosarcoma of different stages. Higher expression of SerpinE2 was shown in osteosarcoma tissues, particularly in tissue from patients with metastasis and a tumor-node-metastasis stage II‑III. Following chemotherapy, the SerpinE2 expression levels were shown to be higher than those at diagnosis. Cell proliferation and colony formation were increased after transfection with SerpinE2 over‑expression vector. Additionally, drug resistance to bortezomib and doxorubicin treatment following SerpinE2 transfection was analyzed. MG‑63 and SAOS‑2 cells showed less sensitivity following transfection with SerpinE2. The cell cycle‑related genes, cyclin‑dependent kinase (CDK)4 and cyclin D1 were positively correlated with SerpinE2 expression in patient‑derived tissue and in osteosarcoma cells. Finally, the high expression of SerpinE2 contributes to poor survival rates in patients with osteosarcoma. In conclusion, high expression of SerpinE2 in osteosarcoma stimulates cell proliferation, promotes drug‑resistance, and results in poor survival by regulating CDK4 and cyclin D1. Thus, SerpinE2 could be a potential target for treatment of patients with osteosarcoma. PMID:27221371

  13. KLF8 knockdown suppresses proliferation and invasion in human osteosarcoma cells

    PubMed Central

    LIN, FENG; SHEN, ZAN; TANG, LI-NA; ZHENG, SHUI-ER; SUN, YUAN-JUE; MIN, DA-LIU; YAO, YANG

    2014-01-01

    Krüppel-like factor 8 (KLF8) is a transcription factor that is important in the regulation of the cell cycle and has a critical role in oncogenic transformation and epithelial to mesenchymal transition (EMT). EMT is a key process in tumor metastasis. Although overexpression of KLF8 has been observed in a variety of human tumor types, the role of KLF8 in human osteosarcoma is yet to be elucidated. The present study aimed to investigate the biological impact of KLF8 on Saos-2 osteosarcoma cells. KLF8 gene expression was knocked down in vitro using a lentivirus-mediated small interfering (si)RNA method. Cell proliferation and cell cycle distribution were evaluated using 3-(4,5)-dimethylthiahiazo(-z-yl)-3,5-di-phenytetrazoliumromide and colony formation assays, and flow cytometry, respectively. Cell invasion was analyzed using a Transwell® invasion assay. Knockdown of KLF8 was found to significantly inhibit proliferation and invasion in osteosarcoma cells. These data suggest that KLF8 may exhibit an important role in osteosarcoma tumorigenesis and that KLF8 may be a potential therapeutic target for the treatment of osteosarcoma. PMID:24604387

  14. Chondroblastic osteosarcoma

    PubMed Central

    Almeida, Etanaiara; Mascarenhas, Bruno Araújo; Cerqueira, Arlei; Medrado, Alena Ribeiro Alves Peixoto

    2014-01-01

    The purpose of this paper is to report a case of chondroblastic osteosarcoma in the region of the maxilla, with 5 months of evolution. The term osteosarcoma refers to a heterogeneous group of malignancies with bone formation or mesenchymal tissue with histopathological evidence of osteogenic differentiation. The pattern of chondroblastic osteosarcoma represents 25% of all reported cases of this neoplasm. Its histopathological diagnosis is based on the predominance of a chondroid matrix formed in the midst of neoplastic cells. A woman patient, 27-year old, melanoderm, presented on extraoral exam with facial asymmetry caused by the a swelling in the premaxillary region with upper lip protrusion. Intraoral exam showed a maxillary tumefaction with involvement of the vestibular and palatine regions. The computerized tomography (CT) analysis exhibited a radiolucent mass with dispersed areas of radiopacity, with poorly defined and indistinct peripheral edges. The patient was subjected to incisional biopsy and histopathological examination showed the presence of a malignant neoplasm of mesenchymal origin characterized by the presence of irregular bone trabeculae dispersed among mildly atypical chondroblastic cells. The World Health Organization (WHO) recognizes several variants that differ in location, clinical behavior and degree of cellular atypia. The conventional or classical osteosarcoma is the most frequent variant, which develops within the medullary bone. This report illustrates the rapid evolution of one of the histological variants of osteosarcoma. PMID:25949008

  15. Cell growth inhibition and apoptotic effect of the rexinoid 6-OH-11-O-hydroxyphenantrene on human osteosarcoma and mesenchymal stem cells.

    PubMed

    Dozza, Barbara; Papi, Alessio; Lucarelli, Enrico; Scotlandi, Katia; Pierini, Michela; Tresca, Giuseppina; Donati, Davide; Orlandi, Marina

    2012-02-01

    Natural derivatives of vitamin A, including all-trans-retinoic acid (ATRA), commonly known as retinoids, currently produce favorable results in the treatment of many types of tumors. The rexinoid 6-OH-11-O-hydroxyphenantrene (IIF) is a synthetic derivative of ATRA. Previous in vitro and in vivo studies demonstrated that IIF is able to induce growth inhibition of various cancer cells and is a potent apoptosis-inducing agent with clinical potential. Osteosarcoma (OS) is the most common type of bone cancer, characterized by a rising aggressiveness. Recent evidences suggest that mesenchymal stem cells (MSC) may favour tumor growth and progression. Thus, it is important to investigate whether a compound with potential anti-tumoral properties such as IIF affects not only tumor cells but also MSC. The current study is an attempt to understand the mode of the potential cytotoxicity of IIF on OS cells and MSC. The response to IIF treatment of osteosarcoma SaOS-2, MG63, and U2OS cells and of bone marrow-derived MSC was the subject of investigation. The results showed that IIF significantly inhibited cell growth in OS cell lines and MSC in both a time- and dose-dependent manner, as evaluated by methylene blue assay. This was also associated with altered cell morphology and an increase in cell death with the involvement of apoptosis as demonstrated by NucleoCounter, Hoechst 33342 staining and FACS analysis. No cell death and apoptosis was found in U2OS cells. Analysis of cells treated with 20 and 40μM IIF for 24h by western blot suggests the activation of initiator caspase 9, indicating the involvement of caspases in inducing apoptosis. Furthermore, IIF upregulated the expression of the pro-apoptotic protein Bax and downregulated the anti-apoptotic protein Bcl2. For the first time, our results collectively provide an evidence for cell growth inhibition and activation of apoptosis in human OS cells and MSC by IIF. These results confirm that IIF may be an effective compound for

  16. Polyoxometalates as antitumor agents: Bioactivity of a new polyoxometalate with copper on a human osteosarcoma model.

    PubMed

    León, I E; Porro, V; Astrada, S; Egusquiza, M G; Cabello, C I; Bollati-Fogolin, M; Etcheverry, S B

    2014-10-01

    Polyoxometalates (POMs) are early transition metal oxygen anion clusters. They display interesting biological effects mainly related to their antiviral and antitumor properties. On the other hand, copper compounds also show different biological and pharmacological effects in cell culture and in animal models. We report herein for the first time, a detailed study of the mechanisms of action of a copper(II) compound of the group of HPOMs with the formula K7Na3[Cu4(H2O)2(PW9034)2]20H2O (PW9Cu), in a model of human osteosarcoma derived cell line, MG-63. The compound inhibited selectively the viability of the osteosarcoma cells in the range of 25-100μM (p<0.01). Besides, we have clearly shown a more deleterious action of PW9Cu on tumor osteoblasts than in normal cells. Cytotoxicity studies also showed deleterious effects for PW9Cu. The increment of reactive oxygen species (ROS) and the decrease of the GSH/GSSG ratio were involved in the antiproliferative effects of PW9Cu. Moreover, the compound caused cell cycle arrest in G2 phase, triggering apoptosis as determined by flow cytometry. As a whole, these results showed the main mechanisms of the deleterious effects of PW9Cu in the osteosarcoma cell line MG-63, demonstrating that this compound is a promissory agent for cancer treatments. PMID:25451568

  17. Impaired cell cycle regulation of osteoblast-related transcription factor Runx2/Cbfa1 in osteosarcoma cells

    PubMed Central

    San Martin, Inga; Varela, Nelson; Gaete, Marcia; Villegas, Karina; Osorio, Mariana; Tapia, Julio C.; Antonelli, Marcelo; Mancilla, Edna; Lian, Jane B.; Stein, Janet L.; Stein, Gary S; van Wijnen, Andre J.; Galindo, Mario

    2011-01-01

    In mammals, bone differentiation requires the functional expression of the Runx2/Cbfβ heterodimeric complex. Our previous results indicate that Runx2 is also a suppressor of pre-osteoblast proliferation by affecting cell cycle progression at G1. Runx2 levels are cell cycle regulated, oscillating from a maximum during early G1 to a minimum during late G1, S and mitosis phases in proliferating pre-osteoblasts Nevertheless, there is no information concerning Cbfβ gene expression during the cell cycle nor on Runx2 cell cycle expression in bone cancer cells. We analyzed Runx2 and Cbfβ gene expression during cell cycle progression in the pre-osteoblast MC3T3 and osteosarcoma ROS and SaOS cell lines. The expected reduction of Runx2 protein level was observed in MC3T3 cells arrested in late G1 or M phase using mimosine or nocodazole, respectively. However, this reduction was not observed in the cell cycle arrested osteosarcoma cells. Cbfβ protein levels were not regulated during the cell cycle in pre-osteoblasts and osteosarcoma cells. Using cells synchronized in late G1 and mitosis we found that Runx2 levels, but not Cbfβ levels, were cell cycle regulated in MC3T3 osteoblasts. Interestingly, both factors showed a constitutively elevated expression throughout the cell cycle in osteosarcoma cells. Proteasome inhibition by MG132 prevented cell cycle-dependent downregulation of Runx2 protein levels in osteoblasts, but not in osteosarcoma. We propose that Runx2 is involved in tumoral osteosarcoma progression. Altogether, deregulated Runx2 expression throughout the cell cycle seems to constitute a central mechanism in the pathogenesis of osteosarcoma. PMID:19739101

  18. MicroRNA-124 functions as a tumor suppressor and indicates prognosis in human osteosarcoma

    PubMed Central

    HAN, GANG; WANG, YAN; BI, WENZHI; JIA, JINPENG; WANG, WEI

    2015-01-01

    MicroRNA-124 (miR-124) has been demonstrated to be downregulated in numerous human malignancies and correlated with tumor progression. However, its expression and clinical significance in osteosarcoma remains unclear. Thus, the aim of the present study was to explore the effects of miR-124 in osteosarcoma tumorigenesis and development. Using reverse transcription-quantitative polymerase chain reaction, miR-124 expression was detected in primary osteosarcoma tissues and osteosarcoma cell lines. The correlation of miR-124 expression with clinicopathological factors and prognosis was statistically analyzed. MTT, flow cytometric, and Transwell invasion and migration assays were used to test the proliferation, apoptosis, invasion and migration of osteosarcoma cells transfected with miR-124 mimic. It was found that the expression levels of miR-124 in osteosarcoma tissues were significantly lower than those in corresponding noncancerous bone tissues (P<0.001). In addition, miR-124 downregulation more frequently occurred in osteosarcoma specimens with advanced clinical stage (P<0.001), positive distant metastasis (P=0.005) and poor response to neoadjuvant chemotherapy (P=0.013). Univariate and multivariate analysis identified low miR-124 expression as an unfavorable prognostic factor for overall survival. Furthermore, transfection of miR-124 mimic into MG63 cells was able to reduce cell proliferation, invasion and migration, and promote cell apoptosis. These findings indicate that miR-124 may act not only as a novel diagnostic and prognostic marker, but also as a potential target for the molecular therapy of osteosarcoma. PMID:25667613

  19. Hypoxia-induced autophagy as an additional mechanism in human osteosarcoma radioresistance.

    PubMed

    Feng, Helin; Wang, Jin; Chen, Wei; Shan, Baoen; Guo, Yin; Xu, Jianfa; Wang, Ling; Guo, Peng; Zhang, Yingze

    2016-06-01

    Osteosarcoma (OS) responds poorly to radiotherapy, but the mechanism is unclear. We found OS tumor tissues expressed high level of protein HIF-1α, a common biological marker indicative of hypoxia. It is known that hypoxic cells are generally radioresistant because of reduced production of irradiation-induced DNA-damaging reactive oxygen species (ROS) in the anaerobic condition. Here we report another mechanism how hypoxia induces radioresistance. In MG-63 human osteosarcoma cells, hypoxic pretreatment increased the cellular survival in irradiation. These hypoxia-exposed cells displayed compartmental recruitment of GFP-tagged LC3 and expression of protein LC3-II, and restored the radiosensitivity upon autophagy inhibition. The following immunohistochemistry of OS tumor tissue sections revealed upregulated LC3 expression in a correlation with HIF-1α protein level, implying the possibly causative link between hypoxia and autophagy. Further studies in MG-63 cells demonstrated hypoxic pretreatment reduced cellular and mitochondrial ROS production during irradiation, while inhibition of autophagy re-elicited them. Taken together, our study suggests hypoxia can confer cells resistance to irradiation through activated autophagy to accelerate the clearance of cellular ROS products. This might exist in human osteosarcoma as an additional mechanism for radioresistance. PMID:27335774

  20. Regulation of osteosarcoma cell lung metastasis by the c-Fos/AP-1 target FGFR1

    PubMed Central

    Weekes, Daniel; Zandueta, Carolina; Perurena, Naiara; Thomas, David P; Sunters, Andrew; Vuillier, Céline; Bozec, Aline; El-Emir, Ethaar; Miletich, Isabelle; Patiño-Garcia, Ana; Lecanda, Fernando; Grigoriadis, Agamemnon E

    2015-01-01

    Osteosarcoma is the most common primary malignancy of the skeleton and is prevalent in children and adolescents. Survival rates are poor and have remained stagnant due to chemoresistance and the high propensity to form lung metastases. In this study, we used in vivo transgenic models of c-fos oncogene-induced osteosarcoma and chondrosarcoma in addition to c-Fos-inducible systems in vitro to investigate downstream signaling pathways that regulate osteosarcoma growth and metastasis. Fgfr1 was identified as a novel c-Fos/AP-1 regulated gene. Induction of c-Fos in vitro in osteoblasts and chondroblasts caused an increase in Fgfr1 RNA and FGFR1 protein expression levels that resulted in increased and sustained activation of MAPKs, morphological transformation and increased anchorage-independent growth in response to FGF2 ligand treatment. High levels of FGFR1 protein and activated pFRS2α signalling were observed in murine and human osteosarcomas. Pharmacological inhibition of FGFR1 signalling blocked MAPK activation and colony growth of osteosarcoma cells in vitro. Orthotopic injection in vivo of FGFR1 silenced osteosarcoma cells caused a marked 2- to 5-fold decrease in spontaneous lung metastases. Similarly, inhibition of FGFR signalling in vivo with the small molecule inhibitor AZD4547 markedly reduced the number and size of metastatic nodules. Thus, deregulated FGFR signalling plays an important role in osteoblast transformation and osteosarcoma formation and regulates the development of lung metastases. Our findings support the development of anti-FGFR inhibitors as potential antimetastatic therapy. PMID:26387545

  1. Regulation of osteosarcoma cell lung metastasis by the c-Fos/AP-1 target FGFR1.

    PubMed

    Weekes, D; Kashima, T G; Zandueta, C; Perurena, N; Thomas, D P; Sunters, A; Vuillier, C; Bozec, A; El-Emir, E; Miletich, I; Patiño-Garcia, A; Lecanda, F; Grigoriadis, A E

    2016-06-01

    Osteosarcoma is the most common primary malignancy of the skeleton and is prevalent in children and adolescents. Survival rates are poor and have remained stagnant owing to chemoresistance and the high propensity to form lung metastases. In this study, we used in vivo transgenic models of c-fos oncogene-induced osteosarcoma and chondrosarcoma in addition to c-Fos-inducible systems in vitro to investigate downstream signalling pathways that regulate osteosarcoma growth and metastasis. Fgfr1 (fibroblast growth factor receptor 1) was identified as a novel c-Fos/activator protein-1(AP-1)-regulated gene. Induction of c-Fos in vitro in osteoblasts and chondroblasts caused an increase in Fgfr1 RNA and FGFR1 protein expression levels that resulted in increased and sustained activation of mitogen-activated protein kinases (MAPKs), morphological transformation and increased anchorage-independent growth in response to FGF2 ligand treatment. High levels of FGFR1 protein and activated pFRS2α signalling were observed in murine and human osteosarcomas. Pharmacological inhibition of FGFR1 signalling blocked MAPK activation and colony growth of osteosarcoma cells in vitro. Orthotopic injection in vivo of FGFR1-silenced osteosarcoma cells caused a marked twofold to fivefold decrease in spontaneous lung metastases. Similarly, inhibition of FGFR signalling in vivo with the small-molecule inhibitor AZD4547 markedly reduced the number and size of metastatic nodules. Thus deregulated FGFR signalling has an important role in osteoblast transformation and osteosarcoma formation and regulates the development of lung metastases. Our findings support the development of anti-FGFR inhibitors as potential antimetastatic therapy. PMID:26387545

  2. MicroRNA-34a inhibits human osteosarcoma proliferation by downregulating ether à go-go 1 expression.

    PubMed

    Wu, Xinyu; Zhong, Daixing; Gao, Quan; Zhai, Wenliang; Ding, Zhenqi; Wu, Jin

    2013-01-01

    Aberrant expression of MicroRNAs (miRNAs) has been implicated in several types of cancer. As a direct target gene of p53, miR-34a has been suggested to mediate the tumor suppressor function of p53. Ether à go-go 1 (Eag1) channel is overexpressed in a variety of cancers and plays important roles in cancer progression. However, the link between miR-34a and Eag1 in cancer is unclear. In this study, we used human osteosarcoma as the model to demonstrate that miR-34a was significantly downregulated in osteosarcoma tissues and cell lines compared with normal brain tissues and osteoblastic cell line. Next we evaluated the role of miR-34a in the regulation of osteosarcoma cell proliferation by CCK-8 and colony formation assays. The results showed that overexpression of miR-34a inhibited the proliferation of MG-63 and Saos-2 cells. Furthermore, xenograft nude mice model showed that miR-34a inhibited osteosarcoma growth in vivo. Mechanistically, we found that overexpression of miR-34a led to decreased Eag1 expression in osteosarcoma cells while inhibition of miR-34a increased Eag1 expression. Taken together, our results suggest that miR-34a could inhibit osteosarcoma growth via the down regulation of Eag1 expression. PMID:23569431

  3. Effect and mechanism of dihydroartemisinin on proliferation, metastasis and apoptosis of human osteosarcoma cells.

    PubMed

    Tang, C; Ao, P Y; Zhao, Y Q; Huang, S Z; Jin, Y; Liu, J J; Luo, J P; Zheng, J; Shi, D P

    2015-01-01

    Osteosarcoma represents an aggressive type of bone malignancy that poses a significant health threat. The objective of the current study was to analyze the effect and mechanism of dihydroartemisinin (DHA) on the proliferation, metastasis and apoptosis of human osteosarcoma cells. A gradient concentration of DHA (15, 25 and 35 μmol.L-1) was used to stimulate the cells, along with control and Dimethyl sulfoxide (DMSO). The phenotypic outcomes were characterized using MTT assay, clone formation assay, Hoechst 33258 staining assay, luciferase reporter plasmid assay, Western blot and wound healing assay. In addition, IBM SPSS Statistics 18.0 software was applied for statistical analysis and all experimental data were expressed as mean ± s.d. Analysis of variance (ANOVA) was applied to compare the differences among multiple groups. Our results demonstrated that DHA inhibited the proliferation and metastasis of osteosarcoma cells and promoted the apoptosis in the cytomorphosis. PMID:26753652

  4. Safety Concern between Autologous Fat Graft, Mesenchymal Stem Cell and Osteosarcoma Recurrence

    PubMed Central

    Perrot, Pierre; Rousseau, Julie; Bouffaut, Anne-Laure; Rédini, Françoise; Cassagnau, Elisabeth; Deschaseaux, Frédéric; Heymann, Marie-Françoise; Heymann, Dominique; Duteille, Franck; Trichet, Valérie; Gouin, François

    2010-01-01

    Background Osteosarcoma is the most common malignant primary bone tumour in young adult treated by neo adjuvant chemotherapy, surgical tumor removal and adjuvant multidrug chemotherapy. For correction of soft tissue defect consecutive to surgery and/or tumor treatment, autologous fat graft has been proposed in plastic and reconstructive surgery. Principal Findings We report here a case of a late local recurrence of osteosarcoma which occurred 13 years after the initial pathology and 18 months after a lipofilling procedure. Because such recurrence was highly unexpected, we investigated the possible relationship of tumor growth with fat injections and with mesenchymal stem/stromal cell like cells which are largely found in fatty tissue. Results obtained in osteosarcoma pre-clinical models show that fat grafts or progenitor cells promoted tumor growth. Significance These observations and results raise the question of whether autologous fat grafting is a safe reconstructive procedure in a known post neoplasic context. PMID:20544017

  5. mRNA expression profiles of primary high-grade central osteosarcoma are preserved in cell lines and xenografts

    PubMed Central

    2011-01-01

    Background Conventional high-grade osteosarcoma is a primary malignant bone tumor, which is most prevalent in adolescence. Survival rates of osteosarcoma patients have not improved significantly in the last 25 years. Aiming to increase this survival rate, a variety of model systems are used to study osteosarcomagenesis and to test new therapeutic agents. Such model systems are typically generated from an osteosarcoma primary tumor, but undergo many changes due to culturing or interactions with a different host species, which may result in differences in gene expression between primary tumor cells, and tumor cells from the model system. We aimed to investigate whether gene expression profiles of osteosarcoma cell lines and xenografts are still comparable to those of the primary tumor. Methods We performed genome-wide mRNA expression profiling on osteosarcoma biopsies (n = 76), cell lines (n = 13), and xenografts (n = 18). Osteosarcoma can be subdivided into several histological subtypes, of which osteoblastic, chondroblastic, and fibroblastic osteosarcoma are the most frequent ones. Using nearest shrunken centroids classification, we generated an expression signature that can predict the histological subtype of osteosarcoma biopsies. Results The expression signature, which consisted of 24 probes encoding for 22 genes, predicted the histological subtype of osteosarcoma biopsies with a misclassification error of 15%. Histological subtypes of the two osteosarcoma model systems, i.e. osteosarcoma cell lines and xenografts, were predicted with similar misclassification error rates (15% and 11%, respectively). Conclusions Based on the preservation of mRNA expression profiles that are characteristic for the histological subtype we propose that these model systems are representative for the primary tumor from which they are derived. PMID:21933437

  6. Genetically engineered pre-microRNA-34a prodrug suppresses orthotopic osteosarcoma xenograft tumor growth via the induction of apoptosis and cell cycle arrest

    PubMed Central

    Zhao, Yong; Tu, Mei-Juan; Wang, Wei-Peng; Qiu, Jing-Xin; Yu, Ai-Xi; Yu, Ai-Ming

    2016-01-01

    Osteosarcoma (OS) is the most common primary malignant bone tumor in children, and microRNA-34a (miR-34a) replacement therapy represents a new treatment strategy. This study was to define the effectiveness and safety profiles of a novel bioengineered miR-34a prodrug in orthotopic OS xenograft tumor mouse model. Highly purified pre-miR-34a prodrug significantly inhibited the proliferation of human 143B and MG-63 cells in a dose dependent manner and to much greater degrees than controls, which was attributed to induction of apoptosis and G2 cell cycle arrest. Inhibition of OS cell growth and invasion were associated with release of high levels of mature miR-34a from pre-miR-34a prodrug and consequently reduction of protein levels of many miR-34a target genes including SIRT1, BCL2, c-MET, and CDK6. Furthermore, intravenous administration of in vivo-jetPEI formulated miR-34a prodrug significantly reduced OS tumor growth in orthotopic xenograft mouse models. In addition, mouse blood chemistry profiles indicated that therapeutic doses of bioengineered miR-34a prodrug were well tolerated in these animals. The results demonstrated that bioengineered miR-34a prodrug was effective to control OS tumor growth which involved the induction of apoptosis and cell cycle arrest, supporting the development of bioengineered RNAs as a novel class of large molecule therapeutic agents. PMID:27216562

  7. Fluoroquinolone-Mediated Inhibition of Cell Growth, S-G2/M Cell Cycle Arrest, and Apoptosis in Canine Osteosarcoma Cell Lines

    PubMed Central

    Seo, Kyoung won; Holt, Roseline; Jung, Yong-Sam; Rodriguez, Carlos O.; Chen, Xinbin; Rebhun, Robert B.

    2012-01-01

    Despite significant advancements in osteosarcoma research, the overall survival of canine and human osteosarcoma patients has remained essentially static over the past 2 decades. Post-operative limb-spare infection has been associated with improved survival in both species, yet a mechanism for improved survival has not been clearly established. Given that the majority of canine osteosarcoma patients experiencing post-operative infections were treated with fluoroquinolone antibiotics, we hypothesized that fluoroquinolone antibiotics might directly inhibit the survival and proliferation of canine osteosarcoma cells. Ciprofloxacin or enrofloxacin were found to inhibit p21WAF1 expression resulting in decreased proliferation and increased S-G2/M accumulation. Furthermore, fluoroquinolone exposure induced apoptosis of canine osteosarcoma cells as demonstrated by cleavage of caspase-3 and PARP, and activation of caspase-3/7. These results support further studies examining the potential impact of quinolones on survival and proliferation of osteosarcoma. PMID:22927942

  8. Fluoroquinolone-mediated inhibition of cell growth, S-G2/M cell cycle arrest, and apoptosis in canine osteosarcoma cell lines.

    PubMed

    Seo, Kyoung won; Holt, Roseline; Jung, Yong-Sam; Rodriguez, Carlos O; Chen, Xinbin; Rebhun, Robert B

    2012-01-01

    Despite significant advancements in osteosarcoma research, the overall survival of canine and human osteosarcoma patients has remained essentially static over the past 2 decades. Post-operative limb-spare infection has been associated with improved survival in both species, yet a mechanism for improved survival has not been clearly established. Given that the majority of canine osteosarcoma patients experiencing post-operative infections were treated with fluoroquinolone antibiotics, we hypothesized that fluoroquinolone antibiotics might directly inhibit the survival and proliferation of canine osteosarcoma cells. Ciprofloxacin or enrofloxacin were found to inhibit p21(WAF1) expression resulting in decreased proliferation and increased S-G(2)/M accumulation. Furthermore, fluoroquinolone exposure induced apoptosis of canine osteosarcoma cells as demonstrated by cleavage of caspase-3 and PARP, and activation of caspase-3/7. These results support further studies examining the potential impact of quinolones on survival and proliferation of osteosarcoma. PMID:22927942

  9. Acquisition of anoikis resistance in human osteosarcoma cells does not alter sensitivity to chemotherapeutic agents

    PubMed Central

    Díaz-Montero, C Marcela; McIntyre, Bradley W

    2005-01-01

    Background Chemotherapy-induced cell death can involve the induction of apoptosis. Thus, aberrant function of the pathways involved might result in chemoresistance. Since cell adhesion to the extracellular matrix acts as a survival factor that homeostatically maintains normal tissue architecture, it was tested whether acquisition of resistance to deadhesion-induced apoptosis (anoikis) in human osteosarcoma would result in resistance to chemotherapy. Methods Osteosarcoma cell lines (SAOS-2 and TE-85) obtained from ATCC and were maintained in complete Eagle's MEM medium. Suspension culture was established by placing cells in tissue culture wells coated with poly-HEMA. Cell cytotoxicity was determined using a live/dead cytotoxicity assay. Cell cycle/apoptosis analyses were performed using propidium iodide (PI) staining with subsequent FACS analysis. Apoptosis was also assayed by Annexin-FITC/PI staining. Results Etoposide, adriamycin, vinblastine, cisplatin and paclitaxel were able to induce apoptosis in human osteosarcoma cells SAOS-2 regardless of their anoikis resistance phenotype or the culture conditions (adhered vs. suspended). Moreover, suspended anoikis resistant TE-85 cells (TE-85ar) retained their sensitivity to chemotherapy as well. Conclusion Acquisition of anoikis resistance in human osteosarcoma cells does not result in a generalized resistance to all apoptotic stimuli, including chemotherapy. Moreover, our results suggest that the pathways regulating anoikis resistance and chemotherapy resistance might involve the action of different mediators. PMID:15829011

  10. The flavonoid luteolin enhances doxorubicin-induced autophagy in human osteosarcoma U2OS cells

    PubMed Central

    Zhang, Baoliang; Yu, Xin; Xia, Hong

    2015-01-01

    Luteolin (LUT), a flavone, which is universally present as constituent of medicinal plants as well as some vegetables and spices, has been demonstrated display specific anti-carcinogenic effects. However, the mechanisms by which LUT inhibits human osteosarcoma growth remain unknown. The effects of LUT on cell growth in human osteosarcoma U2OS cells were measured by MTT assay and flowcytometry. The effects of LUT on morphological markers of autophagy in U2OS were analyzed by fluorescence microscopy and electron microscopy. Autophagic markers, beclin1 and LC3 were detected by western blotting. Here, we found that LUT induced autophagy in U2OS and acted as an enhancer to sensitize doxorubicin (DOX)-mediated autophagy signaling. The combined treatment of LUT and DOX greatly decreases the growth of U2OS, showing synergistic cytotoxicity. Our results indicate that LUT in combination with DOX maybe a novel strategy for the treatment of human osteosarcoma. PMID:26629003

  11. Biocompatibility of core@shell particles: cytotoxicity and genotoxicity in human osteosarcoma cells of colloidal silica spheres coated with crystalline or amorphous zirconia.

    PubMed

    Di Virgilio, A L; Arnal, P M; Maisuls, I

    2014-08-01

    The cytotoxicity and genotoxicity of novel colloidal silica spheres coated with crystalline or amorphous zirconia (SiO2@ZrO2(cryst) or SiO2@ZrO2(am)) have been studied in a human osteosarcoma cell line (MG-63), after 24 h exposure. SiO2@ZrO2(cryst) and SiO2@ZrO2(am) had mean diameters of 782±19 and 891±34 nm, respectively. SiO2@ZrO2(cryst) exposure reduced cell viability, with an increase in reactive oxygen species (ROS) and a decrease of the GSH/GSSG ratio. The comet and micronucleus (MN) assays detected DNA damage at 5 and 25 μg/mL, respectively. SiO2@ZrO2(am) induced genotoxic action only at 10 and 50 μg/mL (comet and MN assays), along with a decrease of the GSH/GSSG ratio at 50 μg/mL. Both particles were found inside the cells, forming vesicles; however, none of them entered the nucleus. Our findings show that crystallization of the shell of the amorphous ZrO2 increases both cytotoxicity and genotoxicity. PMID:25344169

  12. Butyl benzyl phthalate suppresses the ATP-induced cell proliferation in human osteosarcoma HOS cells

    SciTech Connect

    Liu, P.-S.; Chen, C.-Y.

    2010-05-01

    Butyl benzyl phthalate (BBP), an endocrine disruptor present in the environment, exerts its genomic effects via intracellular steroid receptors and elicits non-genomic effects by interfering with membrane ion-channel receptors. We previously found that BBP blocks the calcium signaling coupled with P2X receptors in PC12 cells (Liu and Chen, 2006). Osteoblast P2X receptors were recently reported to play a role in cell proliferation and bone remodeling. In this present study, the effects of BBP on ATP-induced responses were investigated in human osteosarcoma HOS cells. These receptors mRNA had been detected, named P2X4, P2X7, P2Y2, P2Y4, P2Y5, P2Y9, and P2Y11, in human osteosarcoma HOS cells by RT-PCR. The enhancement of cell proliferation and the decrease of cytoviability had both been shown to be coupled to stimulation via different concentrations of ATP. BBP suppressed the ATP-induced calcium influx (mainly coupled with P2X) and cell proliferation but not the ATP-induced intracellular calcium release (mainly coupled with P2Y) and cytotoxicity in human osteosarcoma HOS cells. Suramin, a common P2 receptor's antagonist, blocked the ATP-induced calcium signaling, cell proliferation, and cytotoxicity. We suggest that P2X is mainly responsible for cell proliferation, and P2Y might be partially responsible for the observed cytotoxicity. BBP suppressed the calcium signaling coupled with P2X, suppressing cell proliferation. Since the importance of P2X receptors during bone metastasis has recently become apparent, the possible toxic risk of environmental BBP during bone remodeling is a public problem of concern.

  13. In vitro generation of cytotoxic T lymphocyte response using dendritic cell immunotherapy in osteosarcoma

    PubMed Central

    He, Ye-Teng; Zhang, Qing-Min; Kou, Quan-Chun; Tang, Bo

    2016-01-01

    Immunotherapy with tumor lysate-pulsed dendritic cells (DCs) is one of the breakthrough strategies used in the treatment of cancer. However, DC-based immunotherapies for osteosarcoma are limited. In the present study, preclinical studies of a C3H osteosarcoma mouse model (produced by subcutaneous injection of LM8 murine osteosarcoma cells) validated the concept that LM8 cell lysate-pulsed bone marrow-derived DCs may evoke a more potent immune response compared with DCs that have been matured using polyinosinic:polycytidylic acid (poly I:C). A cytotoxic T lymphocyte (CTL) response was established using two groups of C3H mice (n=9) with osteosarcoma; the treatment group consisted of LM8 cell lysate-pulsed DCs and the control group consisted of DCs matured using poly I:C. Each group was immunized with doses of 1×106 cells twice per week for 3 weeks. No difference in the expression of cluster of differentiation markers was identified in the two groups. DCs pulsed with LM8 cell lysate were associated with the increased induction of CTL activity. Serum interferon-γ levels were increased in mice that received DCs pulsed with LM8 cell lysate compared with that in the poly I:C-matured DC group (P<0.041). Serum interleukin-4 was decreased in the treatment group vs. the control group (P<0.033). A mixed lymphocyte reaction assay confirmed that LM8-DC immunotherapy may evoke a significant antigen-specific immune response in a mouse model. The present study reveals promising data on efficacy of a DC-based immunotherapy in the treatment of osteosarcoma; however, further clinical studies are warranted. PMID:27446401

  14. Osteosarcoma After Hematopoietic Stem Cell Transplantation in Children and Adolescents: Case Report and Review of the Literature.

    PubMed

    Kebudi, Rejin; Ozger, Harzem; Kızılocak, Hande; Bay, Sema Buyukkapu; Bilgiç, Bilge

    2016-09-01

    Osteosarcoma as a secondary malignancy after hematopoietic stem cell transplantation (HSCT) is very rare. We present a case and review of 18 other cases reported to date. Our patient underwent HSCT for myelodysplastic syndrome at the age of 4 years. She developed osteosarcoma 13 years later. She underwent surgery after three courses of neoadjuvant chemotherapy followed by chemotherapy and mifamurtide. She has no evidence of disease 28 months after termination of chemotherapy. In 18 other cases of secondary osteosarcoma in the literature, 15 had received total body irradiation, eight had received alkylating agents, and six had received etoposide. The median interval from HSCT to the onset of osteosarcoma was 6.5 years (range 2.5-15.3), which confirms that children undergoing HSCT should be followed up for many years. In conclusion, osteosarcoma must be included in the differential diagnosis among solid tumors that may develop following HSCT. PMID:27187839

  15. Ampelopsin suppresses TNF-α-induced migration and invasion of U2OS osteosarcoma cells.

    PubMed

    Liu, Changying; Zhao, Pengfei; Yang, Yubao; Xu, Xiaodong; Wang, Liang; Li, Bo

    2016-06-01

    Ampelopsin has been suggested as a novel anticancer agent, however, there is no evidence regarding its direct effect on the migration and invasion of osteosarcoma cells. The aims of the present study were to investigate the influence of ampelopsin on the migration and invasion of osteosarcoma cells and to clarify the underlying mechanisms. Scratch wound healing and Transwell assays were used to measure the migratory and invasive activities of the cells, respectively. The protein and RNA levels of matrix metalloproteinase-2 (MMP-2) were detected with western blot and RT-qPCR, respectively, following stimulation with tumor necrosis factor‑α (TNF-α) and ampelopsin. The expression levels of phospho‑ and total-p38MAPK were detected using western blot analysis. Additionally, SB203580, an inhibitor of p38MAPK, was used to investigate the effect of TNF‑α and ampelopsin. The results demonstrated that TNF‑α upregulated the expression level of MMP‑2 and promoted the migration and invasion of osteosarcoma cells. TNF‑α also activated the p38MAPK pathway, and SB203580 significantly inhibited the effect of TNF‑α on MMP‑2 expression. The application of ampelopsin abolished the effects of TNF‑α on the activation of the p38MAPK pathway and the expression of MMP‑2, and downregulated the migration and invasion of the osteosarcoma cells. These results demonstrated that ampelopsin inhibits the TNF‑α‑induced migration and invasion of osteosarcoma cells, and that the effect of ampelopsin was mediated by p38MAPK/MMP‑2 signaling. PMID:27082056

  16. Effectiveness evaluation of dendritic cell immunotherapy for osteosarcoma on survival rate and in vitro immune response.

    PubMed

    Fang, X; Jiang, C; Xia, Q

    2015-01-01

    The aim of this study was to investigate the effects of dendritic cell (DC) therapy in osteosarcoma. Bone marrow DCs from Wistar (allograft group) and Sprague Dawley (SD) (homograft group) rats were electrically fused with the SD-derived osteosarcoma cell line UMR106 to generate a DC-osteosarcoma fusion (DOF) tumor vaccine, which was co-incubated with SD T lymphocytes to stimulate T cell proliferation. CD8+ and CD4+ cell percentages were measured by flow cytometry; tumor-cytotoxic effects of cytotoxic T lymphocytes (CTLs) were measured by the MTT assay. Active immunotherapy was applied to SD osteosarcoma model rats via subcutaneous injection of the tumor vaccine. Significant potentiation of T lymphocyte proliferation was observed in both groups. In the homograft group, the CD8+/CD4+ ratio was elevated to 78.2 from 55.1% after stimulation (P < 0.05) whereas the CD4+ cell percentage was reduced from 61.3 to 21.2% (P < 0.05). Similarly, in the allograft group the CD8+ and CD4+ cell percentages significantly increased (33.8 to 69.6%) or decreased (61.3 to 28.1%) after stimulation, respectively (P < 0.05). The preferential homograft group response was not significant (P > 0.05). Induced UMR106- specific CTLs showed a significantly higher tumor-cytotoxic effect after stimulation (P < 0.05). After DOF active immunotherapy, tumor bodies displayed atrophy or disappearance, leading to higher survival times and rates (60 and 70% in the allograft and homograft groups) (P < 0.05). This study demonstrated that osteosarcoma immunotherapy using a DC-fused tumor vaccine can effectively stimulate T lymphocyte proliferation and induce the tumor-cytotoxic activity of CTLs. PMID:26436501

  17. p53-Dependent Activation of microRNA-34a in Response to Etoposide-Induced DNA Damage in Osteosarcoma Cell Lines Not Impaired by Dominant Negative p53 Expression

    PubMed Central

    Novello, Chiara; Pazzaglia, Laura; Conti, Amalia; Quattrini, Irene; Pollino, Serena; Perego, Paola; Picci, Piero; Benassi, Maria Serena

    2014-01-01

    Osteosarcoma (OS) is the most common primary malignant bone tumor and prevalently occurs in the second decade of life. Etoposide, a chemotherapeutic agent used in combined treatments of recurrent human OS, belongs to the topoisomerase inhibitor family and causes DNA breakage. In this study we evaluated the cascade of events determined by etoposide-induced DNA damage in OS cell lines with different p53 status focusing on methylation status and expression of miR-34a that modulate tumor cell growth and cell cycle progression. Wild-type p53 U2-OS cells and U2-OS cells expressing dominant-negative form of p53 (U2- OS175) were more sensitive to etoposide than p53-deficient MG63 and Saos-2 cells, showing increased levels of unmethylated miR-34a, reduced expression of CDK4 and cell cycle arrest in G1 phase. In contrast, MG63 and Saos-2 cell lines presented aberrant methylation of miR-34a promoter gene with no miR-34a induction after etoposide treatment, underlining the close connection between p53 expression and miR-34a methylation status. Consistently, in p53siRNA transfected U2-OS cells we observed loss of miR-34a induction after etoposide exposure associated with a partial gain of gene methylation and cell cycle progress towards G2/M phase. Our results suggest that the open and unmethylated conformation of the miR-34a gene may be regulated by p53 able to bind the gene promoter. In conclusion, cell response to etoposide-induced DNA damage was not compromised in cells with dominant-negative p53 expression. PMID:25490093

  18. The HIF-1α/CXCR4 pathway supports hypoxia-induced metastasis of human osteosarcoma cells.

    PubMed

    Guan, Guofeng; Zhang, Yinglong; Lu, Yao; Liu, Lijuan; Shi, Doufei; Wen, Yanhua; Yang, Lianjia; Ma, Qiong; Liu, Tao; Zhu, Xiaodong; Qiu, Xiuchun; Zhou, Yong

    2015-02-01

    HIF-1α mediates hypoxia-induced expression of the chemokine receptor CXCR4 and contributes to metastasis in many different cancers. We have previously shown that hypoxia promotes migration of human osteosarcoma cells by activating the HIF-1α/CXCR4 pathway. Here, immunohistochemical analysis showed that unlike control osteochondroma samples, osteosarcoma specimens were characterized by elevated expression levels of HIF-1α and CXCR4. Moreover, we found that hypoxia-induced invasiveness was more pronounced in high metastatic potential F5M2 osteosarcoma cells than in low metastatic potential F4 cells, and that this induction was sensitive to treatment with the CXCR4 antagonist AMD3100 and the HIF-1α inhibitor KC7F2. Interestingly, hypoxia-induced CXCR4 expression persisted after cultured osteosarcoma cells were returned to normoxic conditions. These observations were confirmed by experiments in a mouse model of osteosarcoma lung metastasis showing that hypoxia stimulation of pulmonary metastasis was greater in F5M2 than in F4 cells, and was sensitive to treatment with AMD3100. Our study provides further evidence of the contributions of hypoxia and the HIF-1α/CXCR4 pathway to the progression of osteosarcoma, and suggests that this axis might be efficiently leveraged in the development of novel osteosarcoma therapeutics. PMID:25444927

  19. Deciphering the effect of an oxovanadium(iv) complex with the flavonoid chrysin (VOChrys) on intracellular cell signalling pathways in an osteosarcoma cell line.

    PubMed

    León, Ignacio E; Díez, Paula; Etcheverry, Susana B; Fuentes, Manuel

    2016-08-01

    Vanadium complexes were studied during recent years and considered as a representative of a new class of non-platinum metal antitumor agents in combination with their low toxicity. However, a few challenges still remain in the discovery of new molecular targets for these novel metal-based drugs. The study of cell signaling pathways related to vanadium drugs, which is highly critical for identifying specific targets that play an important role in the antitumor activity of vanadium compounds, is scarce. This research deals with the alterations in intracellular signaling pathways promoted by an oxovanadium(iv) complex with the flavonoid chrysin [VO(chrysin)2EtOH]2 (VOChrys) in a human osteosarcoma cell line (MG-63). Herein we report for the first time the effect of [VO(chrysin)2EtOH]2 on the relative abundance of 224 proteins, which are involved in the most common intracellular pathways. Besides, full-length human recombinant (FAK and AKT1) kinases are produced using an in situ IVTT system and then we have evaluated the variation of relative tyrosine-phosphorylation levels caused by the [VO(chrysin)2EtOH]2 compound. The results of the differential protein expression levels reveal that several proteins such as PKB/AKT, PAK, DAPK, Cdk 4, 6 and 7, FADD, AP2, NAK, and JNK, among others, were altered. Moreover, cell signaling pathways related to the PTK2B, FAK, PKC families suggests an important role associated with the antitumor activity of [VO(chrysin)2EtOH]2 was demonstrated. Finally, the effect of this compound on in situ expressed FAK and AKT1 is validated by determining the phosphorylation level, which decreased in the former and increased in the latter. PMID:27175625

  20. MiR-29b suppresses the proliferation and migration of osteosarcoma cells by targeting CDK6.

    PubMed

    Zhu, Kegan; Liu, Lei; Zhang, Junliang; Wang, Yanbo; Liang, Hongwei; Fan, Gentao; Jiang, Zhenhuan; Zhang, Chen-Yu; Chen, Xi; Zhou, Guangxin

    2016-06-01

    Osteosarcoma is the most common primary sarcoma of bone, and it is a leading cause of cancer death among adolescents and young adults. However, the molecular mechanism underlying osteosarcoma carcinogenesis remains poorly understood. Recently, cyclin-dependent kinase 6 (CDK6) was identified as an important oncogene. We found that CDK6 protein level, rather than CDK6 mRNA level, is much higher in osteosarcoma tissues than in normal adjacent tissues, which indicates a post-transcriptional mechanism involved in CDK6 regulation in osteosarcoma. MiRNAs are small non-coding RNAs that repress gene expression at the post-transcriptional level and have widely been shown to play important roles in many human cancers. In this study, we investigated the role of miR-29b as a novel regulator of CDK6 using bioinformatics methods. We demonstrated that CDK6 can be downregulated by miR-29b via binding to the 3'-UTR region in osteosarcoma cells. Furthermore, we identified an inverse correlation between miR-29b and CDK6 protein levels in osteosarcoma tissues. Finally, we examined the function of miR-29b-driven repression of CDK6 expression in osteosarcoma cells. The results revealed that miR-29b acts as a tumor suppressor of osteosarcoma by targeting CDK6 in the proliferation and migration processes. Taken together, our results highlight an important role for miR-29b in the regulation of CDK6 in osteosarcoma and may open new avenues for future osteosarcoma therapies. PMID:27230400

  1. Hydrogel-PLGA delivery system prolongs 2-methoxyestradiol-mediated anti-tumor effects in osteosarcoma cells.

    PubMed

    Maran, Avudaiappan; Dadsetan, Mahrokh; Buenz, Colleen M; Shogren, Kristen L; Lu, Lichun; Yaszemski, Michael J

    2013-09-01

    Osteosarcoma is a bone tumor that affects children and young adults. 2-Methoxyestradiol (2-ME), a naturally occurring estrogen metabolite, kills osteosarcoma cells, but does not affect normal osteoblasts. In order to effectively target osteosarcoma and improve the therapeutic index of the drug 2-ME, we have encapsulated 2-ME in a composite of oligo-(polyethylene glycol) fumarate (OPF) hydrogel and poly (lactic-co-glycolic acid) (PLGA) microspheres and investigated the effect of polymer composition on 2-ME release kinetics and osteosarcoma cell survival. The in vitro study shows that 2-ME can be released in a controlled manner over 21-days. The initial burst releases observed on day 1 were 50% and 32% for OPF and OPF/PLGA composites, respectively. The extended release kinetics show that 100% of the encapsulated 2-ME is released by day 12 from OPF, whereas the OPF/PLGA composites showed a release of 85% on day 21. 2-ME released from the polymers was biologically active and blocked osteosarcoma cell proliferation in vitro. Also, comparison of 2-ME delivery in osteosarcoma cells in culture, shows that direct treatment has no effect after 3 days, whereas polymer-mediated delivery produces anti-tumor effects that could be sustained for 21 days. These findings show that the OPF and PLGA polymeric system may prove to be useful in controlled and sustained delivery of 2-ME and could be further explored in the treatment of osteosarcoma. PMID:23355512

  2. MicroRNA-409-3p inhibits osteosarcoma cell migration and invasion by targeting catenin-δ1.

    PubMed

    Wu, Shifeng; Du, Xinjie; Wu, Manwu; Du, Hechun; Shi, Xiaoliang; Zhang, Tao

    2016-06-10

    Osteosarcoma is the most common primary bone cancer which is associated with early metastatic potential and poor prognosis. However, the molecular mechanisms underlying osteosarcoma progression are not well characterized. Here, we investigated the role of miR-409-3p in osteosarcoma metastasis. Osteosarcoma tissue showed decreased expression of miR-409-3p compared to adjacent non-tumorous tissue. The expression level of miR-409-3p was negatively correlated with osteosarcoma metastasis. Overexpression of miR-409-3p in osteosarcoma cells (U2OS) inhibited cell migration and invasion. Bioinformatics analysis showed that catenin-δ1 (CTNND1, p120-catenin) is a direct target of miR-409-3p. Overexpression of miR-409-3p repressed the expression of catenin-δ1 in U2OS cells at both mRNA and protein levels. Meanwhile, miR-409-3p repressed the activity of luciferase reporter containing the 3'-untranslated region (3'UTR) of CTNND1 gene. Furthermore, expression of catenin-δ1 rescued the inhibitory effect of miR-409-3p on cell migration and invasion. Altogether, these results indicated that miR-409-3p targets catenin-δ1 to repress osteosarcoma metastasis. PMID:26992637

  3. Antibacterial Activity of Elephant Garlic and Its Effect against U2OS Human Osteosarcoma Cells

    PubMed Central

    Huang, Zehao; Ren, Jianwu

    2013-01-01

    Objective(s): The present study was designed to investigate the antibacterial function and pharmacological effect of elephant garlic (Allium ampeloprasum var. ampeloprasum) on U2OS human osteosarcoma cells. Materials and Methods: Seven kinds of bacteria were reconstituted, inoculated and tested in this research to evaluate elephant garlic antibacterial activity. By the means of FACS analysis, cell proliferation assay, confocal laser scanning microscopy and Transwell migration assays, the effect of elephant garlic against U2OS human osteosarcoma cells was unveiled. Rerults: The antimicrobial activity of elephant garlic was stronger than ampicillin when used against Escherichia coli, Bacillus subtilis, Bacillus thuringiensis, Staphylococcus actinomycetes, and gray actinomycetes. Even at a very low concentration (12.5%), elephant garlic still had an antibacterial effect on common bacteria E. coli and S. aureus. The G0/G1 ratio of elephant garlic treated group cells increased while S phase decreased. Elephant garlic extract inhibited the growth of human osteosarcoma cells, U2OS, through preventing the transition from G1 phase to S phase. It reduced osteosarcoma cell, U2OS, invasion ability and significantly increased the proportion of apoptosis. It significantly affected the cytoskeleton generation. Conclusion: Elephant garlic exhibits antibacterial property and has an inhibitory effect on osteosarcoma cells (U2OS) proliferation and cell activity, suggesting the mechanism of its anticancer effects on U2OS human osteosarcoma cells. PMID:24379966

  4. Taurolidine: a novel anti-neoplastic agent induces apoptosis of osteosarcoma cell lines.

    PubMed

    Walters, Denise K; Muff, Roman; Langsam, Bettina; Gruber, Philipp; Born, Walter; Fuchs, Bruno

    2007-08-01

    Taurolidine, the active agent of Taurolin, is a broad spectrum anti-biotic that has been used for over 15 years for the treatment of severe surgical infections. Recently, taurolidine has been shown to possess anti-neoplastic properties in vitro and in vivo against a variety of cancers including ovarian, colon and prostate. In this study we assessed the cytotoxic activity of taurolidine against human osteosarcoma (OS) cell lines and normal human bone cells. Treatment with taurolidine inhibited the growth of all ten osteosarcoma cell lines tested and taurolidine was equally potent against cell lines with and without distinct genetic defects (i.e. p53, Rb). Moreover, taurolidine-induced growth inhibition was found to be associated with a dose dependent increase in the number of apoptotic cells and apoptosis was shown to be caspase-dependent. Taurolidine treatment was also found to inhibit adhesion of OS cell lines. Compared to OS cell lines, normal bone cells in primary culture were found to be less sensitive to the cytotoxic and anti-adhesive effects of taurolidine. These data indicate that taurolidine possesses potent anti-neoplastic activity against osteosarcoma cell lines and may have potential as a novel OS chemotherapeutic agent. PMID:17458504

  5. Downregulation of RSK2 influences the biological activities of human osteosarcoma cells through inactivating AKT/mTOR signaling pathways.

    PubMed

    Qiu, Quanhe; Jiang, Jing; Lin, Liangbo; Cheng, Si; Xin, Daqi; Jiang, Wei; Shen, Jieliang; Hu, Zhenming

    2016-06-01

    RSK2 (90 kDa ribosomal S6 kinase) is a downstream effector of the Ras/ERK (extracellular signal-regulated kinase) signaling pathway that has major functions in cell biological activities, including regulating nuclear signaling, cell cycle progression, cell proliferation, cell growth, protein synthesis, cell migration and cell survival, and is expressed in most types of human malignant tumors, including lung cancer, prostate and breast tumors, skin cancer and osteosarcomas (OS). RSK2 was found to be essential for osteosarcoma formation. To investigate whether RSK2 is expressed at high levels in human osteosarcome tissues and whether its expression is correlated with the aggressive biological behavior of osteosarcoma cell line (OCLs), we assessed the association between RSK2 expression and OS cell progression, as well as the effects of RSK2 inhibition on the biological activities of osteosarcoma cells. We performed immunohistochemistry to analyze the expression of RSK2 in specimens from 30 humans with osteosarcoma, and 15 normal tissues. RSK2 gene expression levels in 30 specimens with osteosarcoma were significantly higher than those of normal tissues. We performed RNA interference on three OCLs to evaluate cell apoptosis, cell growth, cell proliferation, cell motility, chemosensitivity and oncogenicity. After transfection with RSK2 shRNA, increased cell apoptosis, cell growth inhibition, cell cycle progression, weaker cell proliferation, cell migration and weaker tumor formation were observed in all OCLs. These results suggested that RSK2 expression may mediate the biological activities of OS cells and RSK2 may be an effective therapeutic target for the treatment of osteosarcomas. The AKT/mTOR, MAPK/ERK/c-Fos and Bcl2/Bax pathways were analysed to clarify the mechanisms involved. PMID:27082640

  6. Human osteosarcoma CD49f−CD133+ cells: impaired in osteogenic fate while gain of tumorigenicity

    PubMed Central

    Ying, Meidan; Liu, Gang; Shimada, Hiroyuki; Ding, Wanjing; May, William A.; He, Qiaojun; Adams, Gregor B.; Wu, Lingtao

    2014-01-01

    The biological relationships among self-renewal, tumorigenicity, and lineage differentiation of human osteosarcoma-initiating cells (OSIC) remain elusive, making it difficult to identify and distinguish OSIC from osteosarcoma-forming cells (OSFC) for developing OSIC-targeted therapies. Using a new inverse lineage tracking strategy coupled with serial human-to-mouse xenotransplantation, we identified a subpopulation of osteosarcoma cells with OSIC-like properties and sought to distinguish them from their progeny, OSFC. We found that serial transplantation of cells from different osteosarcoma cell lines and primary osteosarcoma tissues progressively increased the CD49f+ subpopulation composing the bulk of the osteosarcoma mass. These CD49f+ cells displayed characteristics of OSFC: limited in vivo tumorigenicity, weak lineage differentiation, more differentiated osteogenic feature, and greater chemo-sensitivity. By contrast, their parental CD49f−CD133+ cells had an inhibited osteogenic fate, together with OSIC-like properties of self-renewal, strong tumorigenicity, and differentiation to CD49f+ progeny. Hence, the CD49f−CD133+ phenotype appears to identify OSIC-like cells that possess strong tumorigenicity correlated with an impaired osteogenic fate and the ability to initiate tumor growth through generation of CD49f+ progeny. These findings advance our understanding of OSIC-like properties and, for the first time, provide a much-needed distinction between OSIC and OSFC in this cancer. PMID:23045288

  7. Knockdown of Akt Sensitizes Osteosarcoma Cells to Apoptosis Induced by Cisplatin Treatment

    PubMed Central

    Zhang, Guoyou; Li, Ming; Zhu, Xiaodong; Bai, Yushu; Yang, Changwei

    2011-01-01

    Akt plays an important role in the inhibition of apoptosis induced by chemotherapy and other stimuli. We therefore investigated if knockdown of Akt2 promoted drug-induced apoptosis in cultured osteosarcoma cells in vitro. SAOS-2 cells were transfected with Akt2 siRNA. The sensitivity of the transformed cell line to the chemotherapeutic drug cisplatin was assessed. Reduced expression of Akt2 did not directly inhibit the growth rate of the transfected cells; however, it significantly increased their sensitivity to cisplatin. Knockdown of Akt2, together with cisplatin treatment, promoted the expression of p53 up-regulated modulator of apoptosis (PUMA). It is possible that the augmentation of cisplatin cytotoxicity may be mediated by PUMA activation. The results of this study suggest that knockdown of Akt2 expression may have therapeutic applications in enhancing the efficacy of chemotherapy in patients with osteosarcoma. PMID:21686164

  8. 6-Gingerol inhibits osteosarcoma cell proliferation through apoptosis and AMPK activation.

    PubMed

    Fan, Jingzhang; Yang, Xin; Bi, Zhenggang

    2015-02-01

    6-Gingerol, a major component of ginger, is demonstrated to possess a variety of pharmacological activities. Despite demonstration of its anti-cancer activity, the exact mechanism underlying the effects of 6-gingerol against sarcoma remains sketchy. In the present study, we investigated the anti-cancer effects of 6-gingerol on osteosarcoma cells. MTT assay was performed to determine cell viability. Phosphorylation and protein levels were determined by immunoblotting. Cell cycle was determined using flow cytometry. Quantitative polymerase chain reaction was employed to determine the changes in the messenger RNA (mRNA) expression of genes. Treatment with 6-gingerol resulted in a significant decrease in the viability of osteosarcoma cells in a dose-dependent fashion. In parallel, the number of cells arrested at the sub-G1 cell cycle phase was significantly increased. The results showed that 6-gingerol induced activation of caspase cascades and regulated cellular levels of Bcl2 and Bax. Moreover, 6-gingerol activated AMP-activated protein kinase (AMPK) signaling associated with the apoptotic pathways. Our findings suggest that 6-gingerol suppresses the growth of osteosarcoma cells. The anti-cancer activity is attributed to the activation of apoptotic signaling and the inhibition of anti-apoptotic signaling incorporating with 6-gingerol-induced AMPK activation. The study identifies a new molecular mechanism by which AMPK is involved in anti-cancer effects of 6-gingerol. PMID:25330949

  9. Overexpression of potassium channel ether à go-go in human osteosarcoma.

    PubMed

    Wu, J; Wu, X; Lian, K; Lin, B; Guo, L; Ding, Z

    2012-01-01

    Human ether à go-go (hEAG) potassium channels are primarily expressed in brain but also frequently overexpressed in solid tumors, which could indicate their potential value for cancer diagnosis and therapy. hEAG1, one member of the hEAG subfamily, has been shown to play a role in neoplastic process. Here we report the expression of hEAG1 in human osteosarcoma detected by a new polyclonal antibody. The full-length hEAG1 cDNA was cloned from human osteosarcoma cell line MG63 by RT-PCR and expressed in Escherichia coli as His tagged protein. The 6His-hEAG1F protein was purified by nickel agarose and used as the antigen to immunize rabbits following standard protocols. The obtained antiserum could detect hEAG1 exogenously expressed in HEK 293 cells. Furthermore, the polyclonal antibody was used to evaluate hEAG1 expression in 42 human osteosarcoma specimens and 19 osteochondromas specimens by immunohistochemistry. hEAG1 was expressed in 71.4% (30/42) osteosarcoma, and 15.8% (3/19) osteochondromas. Moreover, statistical analysis revealed that hEAG1 expression was not dependent on age, sex, site, histology, grade and type in the osteosarcoma specimens. Our data provide evidence that hEAG1 is overexpressed in human osteosarcoma and the hEAG1 polyclonal antibody offers a good tool for further characterization of the oncogenic function of hEAG1 in osteosarcoma. PMID:22248279

  10. Differential regulation and expression of hyaluronan synthases in human articular chondrocytes, synovial cells and osteosarcoma cells.

    PubMed Central

    Recklies, A D; White, C; Melching, L; Roughley, P J

    2001-01-01

    Recently three isoforms of hyaluronan synthase (HAS), the enzyme responsible for hyaluronate/hyaluronan (HA) biosynthesis, have been cloned, allowing us to study their expression pattern. Our objective was to determine which of the HAS isoenzymes were expressed in human articular chondrocytes, synovial fibroblasts and osteosarcoma cells, whether their expression could be modulated by growth factors (insulin-like growth factor-1, basic fibroblast growth factor and transforming growth factor (TGF-beta1) and cytokines [interleukin 1beta1 (IL-1beta)], and whether changes in the rate of HA synthesis by the cells correlated with changes in mRNA levels for one or more of the HAS isoforms. All three HAS isoforms were found to be expressed in the cultured cells analysed in this study, although the relative proportions varied for each cell type. HAS2 mRNA was usually predominant in chondrocytes, whereas synovial cells contained increased amounts of HAS1. HAS3 was always the least abundant message. The rapidly growing osteosarcoma cells contained almost exclusively HAS2 message. HAS usage in uncultured cartilage and synovial tissues was similar to that in the cultured cells, with HAS2 message being the predominant species in cartilage and HAS1 usually being the predominant species in synovium. HA synthesis was stimulated by the growth factors, but the extent of the response was cell-type specific. Synovial cells responded particularly well to IL-1beta, and showed a unique synergistic response when IL-1beta was used in combination with TGF-beta1. This response was much reduced in articular chondrocytes and absent in the osteosarcoma cells. Analysis of changes in HAS message levels indicated that there was often no correlation with the changes in HA secretion following exposure to growth factors. Although HAS-1 mRNA was increased in synovial cells after exposure to TGF-beta1/IL-1beta, the magnitude of the change was far less than the effect on HA synthesis. Our data thus

  11. Estrogen binding, receptor mRNA, and biologic response in osteoblast-like osteosarcoma cells

    SciTech Connect

    Komm, B.S.; Terpening, C.M.; Benz, D.J.; Graeme, K.A.; Gallegos, A.; Korc, M.; Greene, G.L.; O'Malley, B.W.; Haussler, M.R.

    1988-07-01

    High specific activity estradiol labeled with iodine-125 was used to detect approximately 200 saturable, high-affinity (dissociation constant approximately equal to 1.0 nM) nuclear binding sites in rat (ROS 17/2.8) and human (HOS TE85) clonal osteoblast-like osteosarcoma cells. Of the steroids tested, only testosterone exhibited significant cross-reactivity with estrogen binding. RNA blot analysis with a complementary DNA probe to the human estrogen receptor revealed putative receptor transcripts of 6 to 6.2 kilobases in both rat and human osteosarcoma cells. Type I procollagen and transforming growth factor-beta messenger RNA levels were enhanced in cultured human osteoblast-like cells treated with 1 nM estradiol. Thus, estrogen can act directly on osteoblasts by a receptor-mediated mechanism and thereby modulate the extracellular matrix and other proteins involved in the maintenance of skeletal mineralization and remodeling.

  12. S-adenosylmethionine blocks osteosarcoma cells proliferation and invasion in vitro and tumor metastasis in vivo: therapeutic and diagnostic clinical applications

    PubMed Central

    Parashar, Surabhi; Cheishvili, David; Arakelian, Ani; Hussain, Zahid; Tanvir, Imrana; Khan, Haseeb Ahmed; Szyf, Moshe; Rabbani, Shafaat A

    2015-01-01

    Osteosarcoma (OS) is an aggressive and highly metastatic form of primary bone cancer affecting young children and adults. Previous studies have shown that hypomethylation of critical genes is driving metastasis. Here, we examine whether hypermethylation treatment can block OS growth and pulmonary metastasis. Human OS cells LM-7 and MG-63 were treated with the ubiquitous methyl donor S-adenosylmethionine (SAM) or its inactive analog S-adenosylhomocystine (SAH) as control. Treatment with SAM resulted in a dose-dependent inhibition of tumor cell proliferation, invasion, cell migration, and cell cycle characteristics. Inoculation of cells treated with 150 μmol/L SAM for 6 days into tibia or via intravenous route into Fox Chase severe combined immune deficient (SCID) mice resulted in the development of significantly smaller skeletal lesions and a marked reduction in pulmonary metastasis as compared to control groups. Epigenome wide association studies (EWAS) showed differential methylation of several genes involved in OS progression and prominent signaling pathways implicated in bone formation, wound healing, and tumor progression in SAM-treated LM-7 cells. Real-time polymerase chain reaction (qPCR) analysis confirmed that SAM treatment blocked the expression of several prometastatic genes and additional genes identified by EWAS analysis. Immunohistochemical analysis of normal human bone and tissue array from OS patients showed significantly high levels of expression of one of the identified gene platelet-derived growth factor alpha (PDGFA). These studies provide a possible mechanism for the role of DNA demethylation in the development and metastasis of OS to provide a rationale for the use of hypermethylation therapy for OS patients and identify new targets for monitoring OS development and progression. PMID:25619880

  13. Homotypic RANK signaling differentially regulates proliferation, motility and cell survival in osteosarcoma and mammary epithelial cells.

    PubMed

    Beristain, Alexander G; Narala, Swami R; Di Grappa, Marco A; Khokha, Rama

    2012-02-15

    RANKL (receptor activator of NF-κB ligand) is a crucial cytokine for regulating diverse biological systems such as innate immunity, bone homeostasis and mammary gland differentiation, operating through activation of its cognate receptor RANK. In these normal physiological processes, RANKL signals through paracrine and/or heterotypic mechanisms where its expression and function is tightly controlled. Numerous pathologies involve RANKL deregulation, such as bone loss, inflammatory diseases and cancer, and aberrant RANK expression has been reported in bone cancer. Here, we investigated the significance of RANK in tumor cells with a particular emphasis on homotypic signaling. We selected RANK-positive mouse osteosarcoma and RANK-negative preosteoblastic MC3T3-E1 cells and subjected them to loss- and gain-of-RANK function analyses. By examining a spectrum of tumorigenic properties, we demonstrate that RANK homotypic signaling has a negligible effect on cell proliferation, but promotes cell motility and anchorage-independent growth of osteosarcoma cells and preosteoblasts. By contrast, establishment of RANK signaling in non-tumorigenic mammary epithelial NMuMG cells promotes their proliferation and anchorage-independent growth, but not motility. Furthermore, RANK activation initiates multiple signaling pathways beyond its canonical target, NF-κB. Among these, biochemical inhibition reveals that Erk1/2 is dominant and crucial for the promotion of anchorage-independent survival and invasion of osteoblastic cells, as well as the proliferation of mammary epithelial cells. Thus, RANK signaling functionally contributes to key tumorigenic properties through a cell-autonomous homotypic mechanism. These data also identify the likely inherent differences between epithelial and mesenchymal cell responsiveness to RANK activation. PMID:22421365

  14. Anticancer Effects of Geopropolis Produced by Stingless Bees on Canine Osteosarcoma Cells In Vitro

    PubMed Central

    Cinegaglia, Naiara Costa; Bersano, Paulo Ricardo Oliveira; Araújo, Maria José Abigail Mendes; Búfalo, Michelle Cristiane; Sforcin, José Maurício

    2013-01-01

    Geopropolis is produced by indigenous stingless bees from the resinous material of plants, adding soil or clay. Its biological properties have not been investigated, such as propolis, and herein its cytotoxic action on canine osteosarcoma (OSA) cells was evaluated. OSA is a primary bone neoplasm diagnosed in dogs being an excellent model in vivo to study human OSA. spOS-2 primary cultures were isolated from the tumor of a dog with osteosarcoma and incubated with geopropolis, 70% ethanol (geopropolis solvent), and carboplatin after 6, 24, 48, and 72 hours. Cell viability was analyzed by the crystal violet method. Geopropolis was efficient against canine OSA cells in a dose- and time-dependent way, leading to a distinct morphology compared to control. Geopropolis cytotoxic action was exclusively due to its constituents since 70% ethanol (its solvent) had no effect on cell viability. Carboplatin had no effect on OSA cells. Geopropolis exerted a cytotoxic effect on canine osteosarcoma, and its introduction as a possible therapeutic agent in vivo could be investigated, providing a new contribution to OSA treatment. PMID:23690851

  15. Anticancer effects of geopropolis produced by stingless bees on canine osteosarcoma cells in vitro.

    PubMed

    Cinegaglia, Naiara Costa; Bersano, Paulo Ricardo Oliveira; Araújo, Maria José Abigail Mendes; Búfalo, Michelle Cristiane; Sforcin, José Maurício

    2013-01-01

    Geopropolis is produced by indigenous stingless bees from the resinous material of plants, adding soil or clay. Its biological properties have not been investigated, such as propolis, and herein its cytotoxic action on canine osteosarcoma (OSA) cells was evaluated. OSA is a primary bone neoplasm diagnosed in dogs being an excellent model in vivo to study human OSA. spOS-2 primary cultures were isolated from the tumor of a dog with osteosarcoma and incubated with geopropolis, 70% ethanol (geopropolis solvent), and carboplatin after 6, 24, 48, and 72 hours. Cell viability was analyzed by the crystal violet method. Geopropolis was efficient against canine OSA cells in a dose- and time-dependent way, leading to a distinct morphology compared to control. Geopropolis cytotoxic action was exclusively due to its constituents since 70% ethanol (its solvent) had no effect on cell viability. Carboplatin had no effect on OSA cells. Geopropolis exerted a cytotoxic effect on canine osteosarcoma, and its introduction as a possible therapeutic agent in vivo could be investigated, providing a new contribution to OSA treatment. PMID:23690851

  16. MicroRNA-144 inhibits the proliferation, apoptosis, invasion, and migration of osteosarcoma cell line F5M2.

    PubMed

    Cui, Shao-Qian; Wang, Huan

    2015-09-01

    This study is aimed to investigate the role of microRNA-144 (miR-144) in osteosarcoma cell line F5M2 proliferation, apoptosis, invasion, and metastasis. Between 2007 and 2014, 66 cases of osteosarcoma samples in the corresponding adjacent normal tissue samples were selected from surgical resection or biopsy in the Department of Orthopedics, Shengjing Hospital, China Medical University. MiR-144 levels and Ezrin messenger RNA (mRNA) levels in osteosarcoma and the adjacent bone tissues were detected, and clinical and pathological features were analyzed. Exogenous miR-144 was transfected into human osteosarcoma cell lines at two different concentrations (low and high), and the expression levels of miR-144 and Ezrin protein between highly metastatic osteosarcoma cells and lowly metastatic osteosarcoma cells were compared. Real-time polymerase chain reaction (RT-PCR) and Western blot were used for detecting the expression levels of miR-144 or Ezrin protein, respectively. Cell proliferation was measured by methylthiazol tetrazolium (MTT) assay. Cell invasion and migration was evaluated by Transwell assays. Finally, flow cytometry was employed to determine the cell apoptosis. MiR-144 expression in osteosarcoma tissue was significantly lower than that in the surrounding normal bone tissue (P < 0.001), while Ezrin mRNA expression in osteosarcoma tissue was significantly higher than that in the surrounding normal bone tissue (P < 0.001); correlation analysis showed a significant negative correlation between miR-144 and Ezrin mRNA levels (r = 0.982, P < 0.001). MiR-144 and Ezrin mRNA expressions were significantly related with cell metastasis (P < 0.05) but were not related with other clinical factors such as gender, age, tumor location, tumor size, Enneking staging, and Dahlin's histological classification. The results of RT-PCR showed that the expression level of miR-144 in osteosarcoma cells increased after transfected with exogenous miR-144 mimics, and

  17. CCL3 promotes angiogenesis by dysregulation of miR-374b/ VEGF-A axis in human osteosarcoma cells

    PubMed Central

    Chou, Pei-Yu; Wang, Shih-Wei; Chen, Hsien-Te; Lin, Yu-Min; Chiang, I-Ping; Chang, Tzu-Ming; Hsu, Shao-Keh; Chou, Ming-Chih; Tang, Chih-Hsin; Fong, Yi-Chin

    2016-01-01

    Osteosarcoma is the most frequent bone tumor, characterized by a high metastatic potential. However, the crosstalk between chemokine (C-C motif) ligand 3 (CCL3), which facilitates tumor progression and metastasis. Vascular endothelial growth factor-A (VEGF-A), an angiogenesis inducer and a highly specific mitogen for endothelial cells, has not been well explored in human osteosarcoma. Here we demonstrate the correlation of CCL3 and VEGF-A expressions, quantified by immunohistochemistry, with the tumor stage of human osteosarcoma tissues. Furthermore, CCL3 promotes VEGF-A expression in human osteosarcoma cells that subsequently induces human endothelial progenitor cell (EPC) migration and tube formation. Phosphorylation of JNK, ERK, and p38 was found after CCL3 stimulation. In addition, JNK, ERK, and p38 inhibitors also abolished CCL3-induced VEGF-A expression and angiogenesis. We noted that CCL3 reduces the expression of miR-374b and miR-374b mimic by reversing CCL3-promoted VEGF-A expression and angiogenesis in vitro and in vivo. This study shows that CCL3 promotes VEGF-A expression and angiogenesis in human osteosarcoma cells by down-regulating miR-374b expression via JNK, ERK, and p38 signaling pathways. Thus, CCL3 may be a new molecular therapeutic target in osteosarcoma angiogenesis and metastasis. PMID:26713602

  18. Osteosarcoma tissues and cell lines from patients with differing serum alkaline phosphatase concentrations display minimal differences in gene expression patterns.

    PubMed

    Rodrigues, L C de Sá; Holmes, K E; Thompson, V; Piskun, C M; Lana, S E; Newton, M A; Stein, T J

    2016-06-01

    Serum alkaline phosphatase (ALP) concentration is a prognostic factor for osteosarcoma in multiple studies, although its biological significance remains incompletely understood. To determine whether gene expression patterns differed in osteosarcoma from patients with differing serum ALP concentrations, microarray analysis was performed on 18 primary osteosarcoma samples and six osteosarcoma cell lines from dogs with normal and increased serum ALP concentration. No differences in gene expression patterns were noted between tumours or cell lines with differing serum ALP concentration using a gene-specific two-sample t-test. Using a more sensitive empirical Bayes procedure, defective in cullin neddylation 1 domain containing 1 (DCUN1D1) was increased in both the tissue and cell lines of the normal ALP group. Using quantitative PCR (qPCR), differences in DCUN1D1 expression between the two groups failed to reach significance. The homogeneity of gene expression patterns of osteosarcoma associated differing serum ALP concentrations are consistent with previous studies suggesting serum ALP concentration is not associated with intrinsic differences of osteosarcoma cells. PMID:25643733

  19. Osteosarcoma tissues and cell lines from patients with differing serum alkaline phosphatase concentrations display minimal differences in gene expression patterns

    PubMed Central

    de Sá Rodrigues, L. C.; Holmes, K. E.; Thompson, V.; Piskun, C. M.; Lana, S. E.; Newton, M. A.; Stein, T. J.

    2016-01-01

    Serum alkaline phosphatase (ALP) concentration is a prognostic factor for osteosarcoma in multiple studies, although its biological significance remains incompletely understood. To determine whether gene expression patterns differed in osteosarcoma from patients with differing serum ALP concentrations, microarray analysis was performed on 18 primary osteosarcoma samples and six osteosarcoma cell lines from dogs with normal and increased serum ALP concentration. No differences in gene expression patterns were noted between tumours or cell lines with differing serum ALP concentration using a gene-specific two-sample t-test. Using a more sensitive empirical Bayes procedure, defective in cullin neddylation 1 domain containing 1 (DCUN1D1) was increased in both the tissue and cell lines of the normal ALP group. Using quantitative PCR (qPCR), differences in DCUN1D1 expression between the two groups failed to reach significance. The homogeneity of gene expression patterns of osteosarcoma associated differing serum ALP concentrations are consistent with previous studies suggesting serum ALP concentration is not associated with intrinsic differences of osteosarcoma cells. PMID:25643733

  20. Secondary osteosarcoma developing 10 years after chemoradiotherapy for non-small-cell lung cancer.

    PubMed

    Yagishita, Shigehiro; Horinouchi, Hidehito; Yorozu, Takashi; Kitazono, Satoru; Mizugaki, Hidenori; Kanda, Shintaro; Fujiwara, Yutaka; Nokihara, Hiroshi; Yamamoto, Noboru; Mori, Taisuke; Tsuta, Koji; Sumi, Minako; Tamura, Tomohide

    2014-02-01

    A 53-year-old female patient was admitted with pain and a progressively enlarging mass in the right upper chest. Chest computed tomography revealed a mass lesion in the region of the right upper ribs. Ten years prior to this admission, the patient had undergone right lobectomy for lung adenocarcinoma. One year after the surgery, follow-up computed tomography had revealed tumor recurrence in the mediastinal and supraclavicular lymph nodes, and the patient had been treated by chemoradiotherapy. Thereafter, regular follow-up had revealed no evidence of recurrence of the non-small-cell lung cancer. Histopathological findings revealed proliferation of spindle-shaped malignant tumor cells in a background of osteoid, consistent with the diagnosis of osteosarcoma. The location of the tumor was consistent with the radiation field. Based on the clinicopathological findings, the patient was diagnosed as having secondary osteosarcoma occurring as a result of the chemoradiotherapy administered previously for the recurrent non-small-cell lung cancer. Unfortunately, the patient died of rapid progression of the osteosarcoma within a week of admission to the hospital. The autopsy revealed contiguous invasion by the tumor of the heart, with massive thrombus formation. The peripheral pulmonary arteries were diffusely occluded by metastatic tumors. Our case serves to highlight the risk of development of secondary sarcoma as a life-threatening late complication after chemoradiotherapy for locally advanced non-small-cell lung cancer, even after complete cure of the primary tumor. PMID:24338556

  1. miR-125b suppresses the proliferation and migration of osteosarcoma cells through down-regulation of STAT3

    SciTech Connect

    Liu, Li-hong; Li, Hui; Li, Jin-ping; Zhong, Hui; Zhang, Han-chon; Chen, Jia; Xiao, Tao

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. Black-Right-Pointing-Pointer Ectopic restoration of miR-125b suppresses cell proliferation and migration in vitro. Black-Right-Pointing-Pointer STAT3 is the direct and functional downstream target of miR-125b. Black-Right-Pointing-Pointer STAT3 can bind to the promoter region of miR-125b and serves as a transactivator. -- Abstract: There is accumulating evidence that microRNAs are involved in multiple processes in development and tumor progression. Abnormally expressed miR-125b was found to play a fundamental role in several types of cancer; however, whether miR-125b participates in regulating the initiation and progress of osteosarcoma still remains unclear. Here we demonstrate that miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. The ectopic restoration of miR-125b expression in human osteosarcoma cells suppresses proliferation and migration in vitro and inhibits tumor formation in vivo. We further identified signal transducer and activator of transcription 3 (STAT3) as the direct and functional downstream target of miR-125b. Interestingly, we discovered that the expression of miR-125b is regulated by STAT3 at the level of transcription. STAT3 binds to the promoter region of miR-125b in vitro and serves as a transactivator. Taken together, our findings point to an important role in the molecular etiology of osteosarcoma and suggest that miR-125b is a potential target in the treatment of osteosarcoma.

  2. Characterization of mouse model-derived osteosarcoma (OS) cells in vitro and in vivo.

    PubMed

    Uluçkan, Özge; Bakiri, Latifa; Wagner, Erwin F

    2015-01-01

    Osteosarcoma (OS) is the most common primary tumor of bone with a high incidence in children. Treatment options for OS are limited, and once metastasized, the prognosis is very poor. Genetically engineered mouse models (GEMMs) are valuable tools to understand the mechanisms of tumorigenesis and to test possible therapies. In this chapter, we summarize the methods related to the isolation, characterization, and transplantation of OS cells obtained from GEMMs. PMID:25636475

  3. Morphologic characterization of osteosarcoma growth on the chick chorioallantoic membrane

    PubMed Central

    2010-01-01

    Background The chick chorio-allantoic membrane (CAM) assay is a commonly used method for studying angiogenic or anti-angiogenic activities in vivo. The ease of access allows direct monitoring of tumour growth by biomicroscopy and the possibility to screen many samples in an inexpensive way. The CAM model provides a powerful tool to study effects of molecules, which interfere with physiological angiogenesis, or experimental tumours derived from cancer cell lines. We therefore screened eight osteosarcoma cell lines for their ability to form vascularized tumours on the CAM. Findings We implanted 3-5 million cells of human osteosarcoma lines (HOS, MG63, MNNG-HOS, OST, SAOS, SJSA1, U2OS, ZK58) on the CAM at day 10 of embryonic development. Tumour growth was monitored by in vivo biomicroscopy at different time points and tumours were fixed in paraformaldehyde seven days after cell grafting. The tissue was observed, photographed and selected cases were further analyzed using standard histology. From the eight cell lines the MNNG-HOS, U2OS and SAOS were able to form solid tumours when grafted on the CAM. The MNNG-HOS tumours showed the most reliable and consistent growth and were able to penetrate the chorionic epithelium, grow in the CAM stroma and induce a strong angiogenic response. Conclusions Our results show that the CAM assay is a useful tool for studying osteosarcoma growth. The model provides an excellent alternative to current rodent models and could serve as a preclinical screening assay for anticancer molecules. It might increase the speed and efficacy of the development of new drugs for the treatment of osteosarcoma. PMID:20202196

  4. Antiproliferative effect of Tualang honey on oral squamous cell carcinoma and osteosarcoma cell lines

    PubMed Central

    2010-01-01

    Background The treatment of oral squamous cell carcinomas (OSCC) and human osteosarcoma (HOS) includes surgery and/or radiotherapy which often lead to reduced quality of life. This study was aimed to study the antiproliferative activity of local honey (Tualang) on OSCC and HOS cell lines. Methods Several concentrations of Tualang honey (1% - 20%) were applied on OSCC and HOS cell lines for 3, 6, 12, 24, 48 and 72 hours. Morphological characteristics were observed under light and fluorescent microscope. Cell viability was assessed using MTT assay and the optical density for absorbance values in each experiment was measured at 570 nm by an ELISA reader. Detection of cellular apoptosis was done using the Annexin V-FITC Apoptosis Detection Kit. Results Morphological appearance showed apoptotic cellular changes like becoming rounded, reduction in cell number, blebbed membrane and apoptotic nuclear changes like nuclear shrinkage, chromatin condensation and fragmented nucleus on OSCC and HOS cell lines. Cell viability assay showed a time and dose-dependent inhibitory effect of honey on both cell lines. The 50% inhibitory concentration (IC50) for OSCC and HOS cell lines was found to be 4% and 3.5% respectively. The maximum inhibition of cell growth of ≥80% was obtained at 15% for both cell lines. Early apoptosis was evident by flow cytometry where percentage of early apoptotic cells increased in dose and time dependent manner. Conclusion Tualang honey showed antiproliferative effect on OSCC and HOS cell lines by inducing early apoptosis. PMID:20840769

  5. MiR-34a and miR-203 Inhibit Survivin Expression to Control Cell Proliferation and Survival in Human Osteosarcoma Cells

    PubMed Central

    Chen, Xun; Chen, Xiao-Gang; Hu, Xiaojing; Song, Tao; Ou, Xuehai; Zhang, Caiguo; Zhang, Wentao; Zhang, Chun

    2016-01-01

    Elevated expression of survivin is observed in a number of cancer types, including human osteosarcoma. Few studies have demonstrated that survivin expression levels can be considered an independent predictor of survival for human osteosarcoma patients. However, the underlying molecular mechanisms of survivin in the process of human osteosarcoma carcinogenesis remain unclear. In the current study, we evaluated the biological effects of survivin knockdown on osteosarcoma cell proliferation, colony formation rate, and sensitivity to the chemotherapeutic agent cisplatin. We found that two different osteosarcoma cell lines, U2OS and Saos-2, have relatively higher expression levels of survivin, and specific knockdown of survivin resulted in a number of effects, such as inhibition of cell proliferation, decreased colony formation rate, cell cycle arrest at G2/M phase, induction of apoptosis, and increased sensitivity to cisplatin. In addition, we identified two microRNAs, miR-34a and miR-203, that are aberrantly expressed in human osteosarcoma cells and specifically target survivin by inhibiting its expression, therefore repressing osteosarcoma cell maintenance and proliferation. PMID:27326248

  6. Retinal Targets ALDH Positive Cancer Stem Cell and Alters the Phenotype of Highly Metastatic Osteosarcoma Cells

    PubMed Central

    Mu, Xiaodong; Patel, Stuti; Mektepbayeva, Damel; Mahjoub, Adel; Huard, Johnny; Weiss, Kurt

    2015-01-01

    Aldehyde dehydrogenase (ALDH) is a cancer stem cell marker. Retinoic acid has antitumor properties, including the induction of apoptosis and inhibition of proliferation. Retinal, the precursor of retinoic acid, can be oxidized to retinoic acid by dehydrogenases, including ALDH. We hypothesized that retinal could potentially be transformed to retinoic acid with higher efficiency by cancer stem cells, due to the higher ALDH activity. We previously observed that ALDH activity is greater in highly metastatic K7M2 osteosarcoma (OS) cells than in nonmetastatic K12 OS cells. We also demonstrated that ALDH activity correlates with clinical metastases in bone sarcoma patients, suggesting that ALDH may be a therapeutic target specific to cells with high metastatic potential. Our current results demonstrated that retinal preferentially affected the phenotypes of ALDH-high K7M2 cells in contrast to ALDH-low K12 cells, which could be mediated by the more efficient transformation of retinal to retinoic acid by ALDH in K7M2 cells. Retinal treatment of highly metastatic K7M2 cells decreased their proliferation, invasion capacity, and resistance to oxidative stress. Retinal altered the expression of metastasis-related genes. These observations indicate that retinal may be used to specifically target metastatic cancer stem cells in OS. PMID:26819566

  7. On the measurement of human osteosarcoma cell elastic modulus using shear assay experiments.

    PubMed

    Cao, Yifang; Bly, Randy; Moore, Will; Gao, Zhan; Cuitino, Alberto M; Soboyejo, Wole

    2007-01-01

    This paper presents a method for determining the elastic modulus of human osteosarcoma (HOS) cells. The method involves a combination of shear assay experiments and finite element analysis. Following in-situ observations of cell deformation during shear assay experiments, a digital image correlation (DIC) technique was used to determine the local displacement and strain fields. Finite element analysis was then used to determine the Young's moduli of HOS cells. This involved a match of the maximum shear stresses estimated from the experimental shear assay measurements and those calculated from finite element simulations. PMID:17200819

  8. Model for Osteosarcoma-9 as a potent factor in cell survival and resistance to apoptosis

    NASA Astrophysics Data System (ADS)

    Vourvouhaki, Ekaterini; Carvalho, Carla; Aguiar, Paulo

    2007-07-01

    In this paper we use a simple model to explore the function of the gene Osteosarcoma-9 (OS-9). We are particularly interested in understanding the role of this gene as a potent anti-apoptotic factor. The theoretical description is constrained by experimental data from induction of apoptosis in cells where OS-9 is overexpressed. The data available suggest that OS-9 promotes cell viability and confers resistance to apoptosis, potentially implicating OS-9 in the survival of cancer cells. Three different apoptosis-inducing mechanisms were tested and are modeled here. A more complex and realistic model is also discussed.

  9. Genetically Modified T Cells Targeting Interleukin-11 Receptor α-Chain Kill Human Osteosarcoma Cells and Induce the Regression of Established Osteosarcoma Lung Metastases

    PubMed Central

    Cooper, Laurence JN; Hollomon, Mario; Huls, Helen; Kleinerman, Eugenie S

    2013-01-01

    The treatment of osteosarcoma (OS) pulmonary metastases remains a challenge. T cells genetically modified to express a chimeric antigen receptor (CAR), which recognizes a tumor-associated antigen, have shown activity against hematopoetic malignancies in clinical trials, but this requires the identification of a specific receptor on the tumor cell. In the current study, we found that interleukin (IL)-11Rα was selectively expressed on 14 of 16 OS patients’ lung metastases and 4 different human OS cell lines, indicating that IL-11Rα may be a novel target for CAR-specific T-cell therapy. IL-11Rα expression was absent or low in normal organ tissues, with the exception of the GI track. IL-11Rα-CAR-specific T cells were obtained by non-viral gene transfer of Sleeping Beauty DNA plasmids and selectively expanded ex vivo using artificial antigen presenting cells derived from IL-11Rα + K562 cells genetically modified to co-express T-cell co-stimulatory molecules. IL-11Rα-CAR+ T cells killed all 4 OS cell lines in vitro; cytotoxicity correlated with the level of IL-11Rα expression on the tumor cells. Intravenous injection of IL-11Rα-CAR+ T cells into mice resulted in the regression of OS pulmonary metastases with no organ toxicity. Together, the data suggest that IL-11Rα-CAR T cells may represent a new therapy for OS patients with pulmonary metastases. PMID:22075555

  10. Establishment and characterization of a KIT-positive and stem cell factor-producing cell line, KTHOS, derived from human osteosarcoma.

    PubMed

    Hitora, Toshiaki; Yamamoto, Tetsuji; Akisue, Toshihiro; Marui, Takashi; Nakatani, Tetsuya; Kawamoto, Teruya; Nagira, Keiko; Yoshiya, Shinichi; Kurosaka, Masahiro

    2005-02-01

    Osteosarcoma is a malignant bone tumor that commonly affects adolescents and young adults. In the present study a human osteosarcoma cell line, KTHOS, was established from a primary osteosarcoma lesion in the distal femur of a 16-year-old girl. After 106 passages, the KTHOS cell line retained the biological characteristics of osteosarcoma. The KTHOS cells had spindle to pleomorphic cytoplasm with round to ovoid nuclei containing multiple prominent nucleoli, as expected based on the mesodermic origin of osteoblasts. The KTHOS cells were immunoreactive for osteocalcin, osteonectin, stem cell factor (SCF), and KIT (CD117). Reverse transcriptase-polymerase chain reaction indicated that the KTHOS cell line expressed mRNA for SCF and KIT. The KTHOS cells produced relatively high amounts of soluble SCF as determined by enzyme-linked immunosorbent assay. The results suggest that cell proliferation of the KTHOS cell line might be involved in autocrine and/or paracrine loops of the SCF/KIT signaling system. The KTHOS cell line is a novel human osteosarcoma cell line that releases SCF and expresses KIT. This cell line can be used for studies to explore the mechanisms for oncogenesis of human osteosarcomas. PMID:15693848

  11. VEGF Silencing Inhibits Human Osteosarcoma Angiogenesis and Promotes Cell Apoptosis via PI3K/AKT Signaling Pathway.

    PubMed

    Zhao, Jian; Zhang, Zi-Ru; Zhao, Na; Ma, Bao-An; Fan, Qing-Yu

    2015-11-01

    Vascular endothelial growth factor (VEGF) is one of the most effective angiogenic factors that promote generation of tumor vasculature. VEGF is usually up-regulated in multiple cancers including osteosarcoma and glioma. To further explore the potential molecular mechanism that inhibits tumor growth induced by interference of VEGF expression, we constructed a Lv-shVEGF vector and assessed the efficiency of VEGF silencing and its influence in U2OS cells. The data demonstrate that Lv-shVEGF has high inhibition efficiency on VEGF expression, which inhibits proliferation and promotes apoptosis of U2OS cells in vitro. Our results also indicate that inhibition of VEGF expression suppresses osteosarcoma tumor growth in vivo and reduces osteosarcoma angiogenesis. We also found that the activations of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) were considerably reduced after osteosarcoma cells were treated with Lv-shVEGF. Taken together, our data demonstrate that VEGF silencing suppresses cell proliferation, promotes cell apoptosis, and reduces osteosarcoma angiogenesis through inactivation of PI3K/AKT signaling pathway. PMID:27352347

  12. Changes in cell shape are correlated with metastatic potential in murine and human osteosarcomas.

    PubMed

    Lyons, Samanthe M; Alizadeh, Elaheh; Mannheimer, Joshua; Schuamberg, Katherine; Castle, Jordan; Schroder, Bryce; Turk, Philip; Thamm, Douglas; Prasad, Ashok

    2016-01-01

    Metastatic cancer cells for many cancers are known to have altered cytoskeletal properties, in particular to be more deformable and contractile. Consequently, shape characteristics of more metastatic cancer cells may be expected to have diverged from those of their parental cells. To examine this hypothesis we study shape characteristics of paired osteosarcoma cell lines, each consisting of a less metastatic parental line and a more metastatic line, derived from the former by in vivo selection. Two-dimensional images of four pairs of lines were processed. Statistical analysis of morphometric characteristics shows that shape characteristics of the metastatic cell line are partly overlapping and partly diverged from the parental line. Significantly, the shape changes fall into two categories, with three paired cell lines displaying a more mesenchymal-like morphology, while the fourth displaying a change towards a more rounded morphology. A neural network algorithm could distinguish between samples of the less metastatic cells from the more metastatic cells with near perfect accuracy. Thus, subtle changes in shape carry information about the genetic changes that lead to invasiveness and metastasis of osteosarcoma cancer cells. PMID:26873952

  13. Changes in cell shape are correlated with metastatic potential in murine and human osteosarcomas

    PubMed Central

    Lyons, Samanthe M.; Alizadeh, Elaheh; Mannheimer, Joshua; Schuamberg, Katherine; Castle, Jordan; Schroder, Bryce; Turk, Philip; Thamm, Douglas; Prasad, Ashok

    2016-01-01

    ABSTRACT Metastatic cancer cells for many cancers are known to have altered cytoskeletal properties, in particular to be more deformable and contractile. Consequently, shape characteristics of more metastatic cancer cells may be expected to have diverged from those of their parental cells. To examine this hypothesis we study shape characteristics of paired osteosarcoma cell lines, each consisting of a less metastatic parental line and a more metastatic line, derived from the former by in vivo selection. Two-dimensional images of four pairs of lines were processed. Statistical analysis of morphometric characteristics shows that shape characteristics of the metastatic cell line are partly overlapping and partly diverged from the parental line. Significantly, the shape changes fall into two categories, with three paired cell lines displaying a more mesenchymal-like morphology, while the fourth displaying a change towards a more rounded morphology. A neural network algorithm could distinguish between samples of the less metastatic cells from the more metastatic cells with near perfect accuracy. Thus, subtle changes in shape carry information about the genetic changes that lead to invasiveness and metastasis of osteosarcoma cancer cells. PMID:26873952

  14. Mesenchymal stem cells increase proliferation but do not change quiescent state of osteosarcoma cells: Potential implications according to the tumor resection status

    PubMed Central

    Avril, Pierre; Le Nail, Louis-Romée; Brennan, Meadhbh Á.; Rosset, Philippe; De Pinieux, Gonzague; Layrolle, Pierre; Heymann, Dominique; Perrot, Pierre; Trichet, Valérie

    2015-01-01

    Conventional therapy of primary bone tumors includes surgical excision with wide resection, which leads to physical and aesthetic defects. For reconstruction of bone and joints, allografts can be supplemented with mesenchymal stem cells (MSCs). Similarly, adipose tissue transfer (ATT) is supplemented with adipose-derived stem cells (ADSCs) to improve the efficient grafting in the correction of soft tissue defects. MSC-like cells may also be used in tumor-targeted cell therapy. However, MSC may have adverse effects on sarcoma development. In the present study, human ADSCs, MSCs and pre-osteoclasts were co-injected with human MNNG-HOS osteosarcoma cells in immunodeficient mice. ADSCs and MSCs, but not the osteoclast precursors, accelerated the local proliferation of MNNG-HOS osteosarcoma cells. However, the osteolysis and the metastasis process were not exacerbated by ADSCs, MSCs, or pre-osteoclasts. In vitro proliferation of MNNG-HOS and Saos-2 osteosarcoma cells was increased up to 2-fold in the presence of ADSC-conditioned medium. In contrast, ADSC-conditioned medium did not change the dormant, quiescent state of osteosarcoma cells cultured in oncospheres. Due to the enhancing effect of ADSCs/MSCs on in vivo/in vitro proliferation of osteosarcoma cells, MSCs may not be good candidates for osteosarcoma-targeted cell therapy. Although conditioned medium of ADSCs accelerated the cell cycle of proliferating osteosarcoma cells, it did not change the quiescent state of dormant osteosarcoma cells, indicating that ADSC-secreted factors may not be involved in the risk of local recurrence. PMID:26998421

  15. Establishment and characterization of OS 99-1, a cell line derived from a highly aggressive primary human osteosarcoma.

    PubMed

    Gillette, Jennifer M; Gibbs, C Parker; Nielsen-Preiss, Sheila M

    2008-01-01

    Osteosarcoma is the most common form of primary bone cancer. In this study, we established a human osteosarcoma cell line (OS 99-1) from a highly aggressive primary tumor. G-banding karyotype analysis demonstrated a large number of clonal abnormalities, as well as extensive intercellular heterogeneity. Through the use of immunologic, molecular, and biochemical analyses, we characterized protein and gene expression profiles confirming the osteogenic nature of the cells. Further evaluation indicated that OS 99-1 cells maintain the capacity to differentiate in an in vitro mineralization assay as well as form tumors in the in vivo chicken embryo model. This cell line provides a useful tool to investigate the molecular mechanisms contributing to osteosarcoma and may have the potential to serve as a culture system for studies involving bone physiology. PMID:18247100

  16. MicroRNA profiling identifies MiR-195 suppresses osteosarcoma cell metastasis by targeting CCND1.

    PubMed

    Han, Kang; Chen, Xiang; Bian, Na; Ma, Baoan; Yang, Tongtao; Cai, Chengkui; Fan, QingYu; Zhou, Yong; Zhao, Ting Bao

    2015-04-20

    Metastasis is a leading cause of mortality for osteosarcoma patients. The molecular pathological mechanism remains to be elucidated. In the previously study, we established two osteosarcoma cell lines with different metastatic potentials. Differential expressed genes and proteins regarding metastatic ability have been identified. MicroRNAs are important regulators in tumorigenesis and tumor progression. In this study, microRNA microarray was used to assess the differential expressed miRNAs level between these two cell lines. One of the top ranked miRNAs-miR-195 was identified highly expressing in lowly metastatic cells. It was showed that over-expression of miR-195 substantially inhibits migration and invasion of osteosarcoma cells in vitro and pulmonary metastasis formation in vivo. Meanwhile, CCND1 was identified as the target gene of miR-195 and further studied. More importantly, using real-time PCR, we evaluated the expression of miR-195 and CCND1 in osteosarcoma samples from 107 frozen biopsy tissues and 99 formalin- or paraformalin-fixed, paraffin-embedded (FFPE) tissues. Results indicated lowly expressed miR-195 or highly CCND1 correlated with positive overall survival and their expression inversely related to each other. In summary, our study suggests miR-195 functions as a tumor metastasis suppressor gene by down-regulating CCND1 and can be used as a potential target in the treatment of osteosarcoma. PMID:25823925

  17. MicroRNA profiling identifies MiR-195 suppresses osteosarcoma cell metastasis by targeting CCND1

    PubMed Central

    Ma, Baoan; Yang, Tongtao; Cai, Chengkui; Fan, QingYu; Zhou, Yong; Zhao, TingBao

    2015-01-01

    Metastasis is a leading cause of mortality for osteosarcoma patients. The molecular pathological mechanism remains to be elucidated. In the previously study, we established two osteosarcoma cell lines with different metastatic potentials. Differential expressed genes and proteins regarding metastatic ability have been identified. MicroRNAs are important regulators in tumorigenesis and tumor progression. In this study, microRNA microarray was used to assess the differential expressed miRNAs level between these two cell lines. One of the top ranked miRNAs-miR-195 was identified highly expressing in lowly metastatic cells. It was showed that over-expression of miR-195 substantially inhibits migration and invasion of osteosarcoma cells in vitro and pulmonary metastasis formation in vivo. Meanwhile, CCND1 was identified as the target gene of miR-195 and further studied. More importantly, Using real-time PCR, we evaluated the expression of miR-195 and CCND1 in osteosarcoma samples from 107 frozen biopsy tissues and 99 formalin- or paraformalin-fixed, paraffin-embedded (FFPE) tissues. Results indicated lowly expressed miR-195 or highly CCND1 correlated with positive overall survival and their expression inverse relate to each other. In summary, our study suggests miR-195 function as a tumor metastasis suppressor gene by down-regulating CCND1 and can be used as a potential target in the treatment of osteosarcoma. PMID:25823925

  18. Identification of Dormancy-Associated MicroRNAs for the Design of Osteosarcoma-Targeted Dendritic Polyglycerol Nanopolyplexes.

    PubMed

    Tiram, Galia; Segal, Ehud; Krivitsky, Adva; Shreberk-Hassidim, Rony; Ferber, Shiran; Ofek, Paula; Udagawa, Taturo; Edry, Liat; Shomron, Noam; Roniger, Maayan; Kerem, Batsheva; Shaked, Yuval; Aviel-Ronen, Sarit; Barshack, Iris; Calderón, Marcelo; Haag, Rainer; Satchi-Fainaro, Ronit

    2016-02-23

    The presence of dormant, microscopic cancerous lesions poses a major obstacle for the treatment of metastatic and recurrent cancers. While it is well-established that microRNAs play a major role in tumorigenesis, their involvement in tumor dormancy has yet to be fully elucidated. We established and comprehensively characterized pairs of dormant and fast-growing human osteosarcoma models. Using these pairs of mouse tumor models, we identified three novel regulators of osteosarcoma dormancy: miR-34a, miR-93, and miR-200c. This report shows that loss of these microRNAs occurs during the switch from dormant avascular into fast-growing angiogenic phenotype. We validated their downregulation in patients' tumor samples compared to normal bone, making them attractive candidates for osteosarcoma therapy. Successful delivery of miRNAs is a challenge; hence, we synthesized an aminated polyglycerol dendritic nanocarrier, dPG-NH2, and designed dPG-NH2-microRNA polyplexes to target cancer. Reconstitution of these microRNAs using dPG-NH2 polyplexes into Saos-2 and MG-63 cells, which generate fast-growing osteosarcomas, reduced the levels of their target genes, MET proto-oncogene, hypoxia-inducible factor 1α, and moesin, critical to cancer angiogenesis and cancer cells' migration. We further demonstrate that these microRNAs attenuate the angiogenic capabilities of fast-growing osteosarcomas in vitro and in vivo. Treatment with each of these microRNAs using dPG-NH2 significantly prolonged the dormancy period of fast-growing osteosarcomas in vivo. Taken together, these findings suggest that nanocarrier-mediated delivery of microRNAs involved in osteosarcoma tumor-host interactions can induce a dormant-like state. PMID:26815014

  19. SPAG9 controls the cell motility, invasion and angiogenesis of human osteosarcoma cells

    PubMed Central

    YANG, XIAORONG; ZHOU, WENLAI; LIU, SHIQING

    2016-01-01

    Sperm-associated antigen 9 (SPAG9) is an oncoprotein involved in the progression of various human malignancies; however, its role in osteosarcoma (OS) remains poorly evaluated. The present study used Matrigel™ cell migration and invasion assays, tube formation assay, Cell Counting kit-8, quantitative polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay to investigate the role of SPAG9 in OS cell motility, invasion and angiogenesis. The results of the present study demonstrated that SPAG9 expression was upregulated in OS tissues, as compared with adjacent normal tissues, and knockdown of SPAG9 in an OS cell line inhibited cell motility and invasion via inactivation of metalloproteinase (MMP)-2 and MMP-9. Furthermore, the present study demonstrated that silencing of SPAG9 in OS cells inhibited tube formation, the proliferation of human umbilical vascular endothelial cells, and suppressed vascular endothelial growth factor (VEGF) expression and secretion, contributing to a reduction in angiogenesis. The results of the present study indicated that SPAG9 may be an important regulator in OS and may be involved in metastasis. Therefore SPAG9 may be a promising target for the treatment of metastatic OS. PMID:26893659

  20. Self-assembled monolayers of alkanethiolates on surface chemistry groups in osteosarcoma cells

    PubMed Central

    DENG, YING-HU; LI, LI-HUA; HE, JIN; LI, MEI; ZHANG, YU; WANG, XIU-MEI; CUI, FU-ZHAI; XIA, HONG

    2015-01-01

    Cell biomedical behavior is influenced by a number of factors, and the extracellular matrix (ECM) of the cellular microenvironment affects certain cancer cells. In the current study, U-2OS cells were cultured on gold surfaces modified with different terminal chemical groups [methyl (-CH3), amino (-NH2), hydroxyl (-OH) and carboxyl (-COOH)]. The results revealed that different chemical surfaces convey different behaviors. The density of the different functional surfaces was confirmed by atomic force microscopy. Cell morphology, proliferation rate and cell cycle were investigated using scanning electron microscopy, cell counting and flow cytometry. In conclusion, the type of chemical group on a biomaterial is an important property for the growth of osteosarcoma cells; -NH2 and -COOH surfaces sustained visible cell adhesion and promoted cell growth. PMID:25373556

  1. GLIPR1 inhibits the proliferation and induces the differentiation of cancer-initiating cells by regulating miR-16 in osteosarcoma.

    PubMed

    Dong, Jian; Bi, Binna; Zhang, Lianhai; Gao, Kaituo

    2016-09-01

    Osteosarcoma is a common, highly malignant and metastatic bone cancer. Elucidation of the molecular mechanisms of osteosarcoma may further help us to understand the pathogenesis of the disease, and offer novel targets for effective therapies. Human glioma pathogenesis-related protein 1 (GLIPR1) has been found to be downregulated in human cancers. However, its roles have not been reported in osteosarcoma. In the present study, we demonstrated that GLIPR1 protein was downregulated in osteosarcoma. Its overexpression inhibited the proliferation, migration and invasion and induced the differentiation of cancer-initiating cells (CICs) in osteosarcoma. Moreover, GLIPR1 overexpression upregulated miR-16 in osteosarcoma cells. The upregulation suppressed proliferation, migration and invasion as well as induced differentiation of CICs in osteosarcoma. Thus, we conclude that GLIPR1 inhibited the proliferation, migration and invasion and induced the differentiation of CICs by regulating miR-16 in osteosarcoma. The present study provides direct evidence that GLIPR1 is a bona fide tumor suppressor and identified GLIPR1 and miR-16 as key components for regulating the proliferation, migration, invasion and CICs in osteosarcoma. PMID:27460987

  2. Osteosarcoma: Cells-of-Origin, Cancer Stem Cells, and Targeted Therapies

    PubMed Central

    Abarrategi, Ander; Tornin, Juan; Martinez-Cruzado, Lucia; Hamilton, Ashley; Martinez-Campos, Enrique; Rodrigo, Juan P.; González, M. Victoria; Baldini, Nicola; Garcia-Castro, Javier; Rodriguez, Rene

    2016-01-01

    Osteosarcoma (OS) is the most common type of primary solid tumor that develops in bone. Although standard chemotherapy has significantly improved long-term survival over the past few decades, the outcome for those patients with metastatic or recurrent OS remains dismally poor and, therefore, novel agents and treatment regimens are urgently required. A hypothesis to explain the resistance of OS to chemotherapy is the existence of drug resistant CSCs with progenitor properties that are responsible of tumor relapses and metastasis. These subpopulations of CSCs commonly emerge during tumor evolution from the cell-of-origin, which are the normal cells that acquire the first cancer-promoting mutations to initiate tumor formation. In OS, several cell types along the osteogenic lineage have been proposed as cell-of-origin. Both the cell-of-origin and their derived CSC subpopulations are highly influenced by environmental and epigenetic factors and, therefore, targeting the OS-CSC environment and niche is the rationale for many recently postulated therapies. Likewise, some strategies for targeting CSC-associated signaling pathways have already been tested in both preclinical and clinical settings. This review recapitulates current OS cell-of-origin models, the properties of the OS-CSC and its niche, and potential new therapies able to target OS-CSCs. PMID:27366153

  3. Canine osteosarcoma cell lines contain stem-like cancer cells: biological and pharmacological characterization.

    PubMed

    Gatti, Monica; Wurth, Roberto; Vito, Guendalina; Pattarozzi, Alessandra; Campanella, Chiara; Thellung, Stefano; Maniscalco, Lorella; De Maria, Raffaella; Villa, Valentina; Corsaro, Alessandro; Nizzari, Mario; Bajetto, Adriana; Ratto, Alessandra; Ferrari, Angelo; Barbieri, Federica; Florio, Tullio

    2016-05-01

    Cancer stem cells (CSCs) represent a small subpopulation of cells responsible for tumor formation and progression, drug resistance, tumor recurrence and metastasization. CSCs have been identified in many human tumors including osteosarcoma (OSA). CSC distinctive properties are the expression of stem cell markers, sustained growth, self-renewal and tumorigenicity. Here we report the isolation of stem-like cells from two canine OSA cultures, characterized by self-renewal, evaluated by sphere formation ability, differential marker expression, and in vitro proliferation when cultured in a medium containing EGF and bFGF. Current therapies for OSA increased survival time, but prognosis remains poor, due to the development of drug resistance and metastases. Chemotherapy shrinks the tumor mass but CSCs remain unaffected, leading to tumor recurrence. Metformin, a drug for type 2 diabetes, has been shown to possess antitumor properties affecting CSC survival in different human and animal cancers. Here we show that metformin has a significant antiproliferative effect on canine OSA stem-like cells, validating this in vitro model for further pre-clinical drug evaluations. In conclusion, our results demonstrate the feasibility of obtaining CSC-enriched cultures from primary canine OSA cells as a promising model for biological and pharmacological studies of canine and human OSAs. PMID:27506084

  4. Fuse-binding protein 1 is a target of the EZH2 inhibitor GSK343, in osteosarcoma cells.

    PubMed

    Xiong, Xifeng; Zhang, Jinli; Liang, Weiguo; Cao, Wenjuan; Qin, Shengnan; Dai, Libing; Ye, Dongping; Liu, Zhihe

    2016-08-01

    Osteosarcoma is the primary cancer of leaf tissue and is regarded as a differentiation disease caused by genetic and epigenetic changes which interrupt the osteoblast differentiation from mesenchymal stem cells. Because of its high malignancy degree and rapid development, the morbidity and mortality are high. The enhancer of zeste homolog 2 (EZH2) is a catalytic subunit of polycomb repressive complex 2 (PRC2) and has been demonstrated to be involved in a variety of biological processes, such as cell proliferation and program cell death. EZH2 impairs gene expression by catalyzing the tri-methylation of histone H3 lysine 27 (H3K27me3) which controls gene transcription epigenetically. It is reported that EZH2 expression is higher in osteosarcoma than in osteoblastoma and the highest expression of EZH2 is found in osteosarcoma with metastasis. In the past few years, several potent inhibitors of EZH2 have been discovered, and GSK343 is one of them. In this study, we found that GSK343 inhibited osteosarcoma cell viability, restrained cell cycle transition and promoted programmed cell death. GSK343 not only inhibited the expression of EZH2 and its target, c-Myc and H3K27me3, but it also inhibited fuse binding protein 1 (FBP1) expression, another c-Myc regulator. Furthermore, we found that FBP1 physically interacts with EZH2. Based on these results, we believe that GSK343 is a potential molecule for osteosarcoma clinical treatment. Other than the inhibition on EZH2-c-Myc signal pathway, we postulate that the inhibition on FBP1-c-Myc signal pathway is another potential underlying mechanism with which GSK343 inhibits osteosarcoma cell viability. PMID:27278257

  5. Childhood Cancer: Osteosarcoma

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Osteosarcoma KidsHealth > For Parents > Osteosarcoma Print A A A ... kids with osteosarcoma do recover. Risk for Childhood Osteosarcoma Osteosarcoma is most often seen in teenage boys. ...

  6. YKL-40 protein in osteosarcoma tumor tissue.

    PubMed

    Thorn, Andrea Pohly; Daugaard, Søren; Christensen, Lise Hanne; Christensen, Ib Jarle; Petersen, Michael Mørk

    2016-06-01

    YKL-40, a cellular glycoprotein isolated from the human osteosarcoma (OS) cell line MG63, is increased in the blood of patients with various types of cancer, and is found as an independent prognostic variable for survival. YKL-40 is also present with variable intensity in the tumor cells of some cancer types, but survival results have been conflicting. The aim of this study was to investigate the tissue expression of YKL-40 and its possible role as a predictive marker in patients with OS. Forty-eight patients were included in the study. Diagnostic biopsies were analyzed by immunohistochemistry; YKL-staining scores as well as CD14 and CD163 scores were determined, and survival data were determined statistically. A universal intense immunostaining for YKL-40 was found in all tumor cells, but tumor cell/stroma ratio varied, and this ratio (%) served as staining score. Using 24% as mean score to divide the material, patients with tumors of high YKL-40 score had a better survival than patients with low score (p = 0.05). YKL-positive macrophages had no influence on the result. Unexpectedly and contrary to some other findings in cancer tissues, this study has shown a correlation between high YKL-40 tumor cell/matrix ratio and longer overall survival in OS. PMID:26988273

  7. Establishment and characterization of a cisplatin‑resistant human osteosarcoma cell line.

    PubMed

    Han, Tao; Zhu, Xiaoming; Wang, Julei; Zhao, Haien; Ma, Qiong; Zhao, Jian; Qiu, Xiuchun; Fan, Qingyu

    2014-09-01

    The aim of the present study was to establish a new cisplatin-resistant human osteosarcoma cell line and investigate its biological characteristics. The human osteosarcoma cell line SOSP-9607 was exposed to cisplatin by stepwisely increasing the concentrations in the medium to select for the drug-resistant subline, SOSP-9607/CDDP cells. The morphological features were observed using inverted microscopy. The growth curves of SOSP-9607 and SOSP-9607/CDDP cells were drawn to calculate the doubling time. FCM was also used to determine the distribution of the cell cycle. The MTT assay was performed to test the drug resistance of SOSP-9607 and SOSP-9607/CDDP cells. Transwell assay was used to examine the invasive capability of the SOSP-9607/CDDP and SOSP-9607 cells. RT-PCR was performed to determine the mRNA expression levels of drug resistance-related and apoptosis-related genes, MDR1, MRP1, MRP2, LRP, ABCG2, GST-π, Bcl-2 and Bax, in both cell lines. SOSP-9607/CDDP cells exhibited changes in morphology, proliferation rate, doubling time, cell cycle distribution and invasive capability as compared with the SOSP-9607 cells. SOSP-9607/CDDP cells were 6.24-fold resistant to cisplatin in comparison with the SOSP‑9607 cells and also exhibited cross-resistance to methotrexate and adriamycin. SOSP-9607/CDDP cells overexpressed MRP1, MRP2 and GST-π. In conclusion, SOSP-9607/CDDP cells are invaluable tools with which to study the resistance of anticancer drugs and to identify the methods to overcome resistance. PMID:25017716

  8. The HSP90 inhibitor alvespimycin enhances the potency of telomerase inhibition by imetelstat in human osteosarcoma

    PubMed Central

    Hu, Yafang; Bobb, Daniel; He, Jianping; Hill, D Ashley; Dome, Jeffrey S

    2015-01-01

    The unsatisfactory outcomes for osteosarcoma necessitate novel therapeutic strategies. This study evaluated the effect of the telomerase inhibitor imetelstat in pre-clinical models of human osteosarcoma. Because the chaperone molecule HSP90 facilitates the assembly of telomerase protein, the ability of the HSP90 inhibitor alvespimycin to potentiate the effect of the telomerase inhibitor was assessed. The effect of single or combined treatment with imetelstat and alvespimycin on long-term growth was assessed in osteosarcoma cell lines (143B, HOS and MG-63) and xenografts derived from 143B cells. Results indicated that imetelstat as a single agent inhibited telomerase activity, induced telomere shortening, and inhibited growth in all 3 osteosarcoma cell lines, though the bulk cell cultures did not undergo growth arrest. Combined treatment with imetelstat and alvespimycin resulted in diminished telomerase activity and shorter telomeres compared to either agent alone as well as higher levels of γH2AX and cleaved caspase-3, indicative of increased DNA damage and apoptosis. With dual telomerase and HSP90 inhibition, complete growth arrest of bulk cell cultures was achieved. In xenograft models, all 3 treatment groups significantly inhibited tumor growth compared with the placebo-treated control group, with the greatest effect seen in the combined treatment group (imetelstat, p = 0.045, alvespimycin, p = 0.034; combined treatment, p = 0.004). In conclusion, HSP90 inhibition enhanced the effect of telomerase inhibition in pre-clinical models of osteosarcoma. Dual targeting of telomerase and HSP90 warrants further investigation as a therapeutic strategy. PMID:25920748

  9. The HSP90 inhibitor alvespimycin enhances the potency of telomerase inhibition by imetelstat in human osteosarcoma.

    PubMed

    Hu, Yafang; Bobb, Daniel; He, Jianping; Hill, D Ashley; Dome, Jeffrey S

    2015-01-01

    The unsatisfactory outcomes for osteosarcoma necessitate novel therapeutic strategies. This study evaluated the effect of the telomerase inhibitor imetelstat in pre-clinical models of human osteosarcoma. Because the chaperone molecule HSP90 facilitates the assembly of telomerase protein, the ability of the HSP90 inhibitor alvespimycin to potentiate the effect of the telomerase inhibitor was assessed. The effect of single or combined treatment with imetelstat and alvespimycin on long-term growth was assessed in osteosarcoma cell lines (143B, HOS and MG-63) and xenografts derived from 143B cells. Results indicated that imetelstat as a single agent inhibited telomerase activity, induced telomere shortening, and inhibited growth in all 3 osteosarcoma cell lines, though the bulk cell cultures did not undergo growth arrest. Combined treatment with imetelstat and alvespimycin resulted in diminished telomerase activity and shorter telomeres compared to either agent alone as well as higher levels of γH2AX and cleaved caspase-3, indicative of increased DNA damage and apoptosis. With dual telomerase and HSP90 inhibition, complete growth arrest of bulk cell cultures was achieved. In xenograft models, all 3 treatment groups significantly inhibited tumor growth compared with the placebo-treated control group, with the greatest effect seen in the combined treatment group (imetelstat, p = 0.045, alvespimycin, p = 0.034; combined treatment, p = 0.004). In conclusion, HSP90 inhibition enhanced the effect of telomerase inhibition in pre-clinical models of osteosarcoma. Dual targeting of telomerase and HSP90 warrants further investigation as a therapeutic strategy. PMID:25920748

  10. Sirolimus induces apoptosis and reverses multidrug resistance in human osteosarcoma cells in vitro via increasing microRNA-34b expression

    PubMed Central

    Zhou, Yan; Zhao, Rui-hua; Tseng, Kuo-Fu; Li, Kun-peng; Lu, Zhi-gang; Liu, Yuan; Han, Kun; Gan, Zhi-hua; Lin, Shu-chen; Hu, Hai-yan; Min, Da-liu

    2016-01-01

    Aim: Multi-drug resistance poses a critical bottleneck in chemotherapy. Given the up-regulation of mTOR pathway in many chemoresistant cancers, we examined whether sirolimus (rapamycin), a first generation mTOR inhibitor, might induce human osteosarcoma (OS) cell apoptosis and increase the sensitivity of OS cells to anticancer drugs in vitro. Methods: Human OS cell line MG63/ADM was treated with sirolimus alone or in combination with doxorubicin (ADM), gemcitabine (GEM) or methotrexate (MTX). Cell proliferation and apoptosis were detected using CCK-8 assay and flow cytometry, respectively. MiRNAs in the cells were analyzed with miRNA microarray. The targets of miR-34b were determined based on TargetScan analysis and luciferase reporter assays. The expression of relevant mRNA and proteins was measured using qRT-PCR and Western blotting. MiR-34, PAK1 and ABCB1 levels in 40 tissue samples of OS patients were analyzed using qRT-PCR and in situ hybridization assays. Results: Sirolimus (1–100 nmol/L) dose-dependently suppressed the cell proliferation (IC50=23.97 nmol/L) and induced apoptosis. Sirolimus (10 nmol/L) significantly sensitized the cells to anticancer drugs, leading to decreased IC50 values of ADM, GEM and MTX (from 25.48, 621.41 and 21.72 μmol/L to 4.93, 73.92 and 6.77 μmol/L, respectively). Treatment of with sirolimus increased miR-34b levels by a factor of 7.5 in the cells. Upregulation of miR-34b also induced apoptosis and increased the sensitivity of the cells to the anticancer drugs, whereas transfection with miR-34b-AMO, an inhibitor of miR-34b, reversed the anti-proliferation effect of sirolimus. Two key regulators of cell cycle, apoptosis and multiple drug resistance, PAK1 and ABCB1, were demonstrated to be the direct targets of miR-34b. In 40 tissue samples of OS patients, significantly higher miR-34 ISH score and lower PAK5 and ABCB1 scores were detected in the chemo-sensitive group. Conclusion: Sirolimus increases the sensitivity of human OS