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Human Osteosarcoma (human + osteosarcoma)

Distribution by Scientific Domains

Medical Sciences	70%
Life Sciences	30%

Terms modified by Human Osteosarcoma

human osteosarcoma cell

human osteosarcoma cell line

Selected Abstracts

2-methoxyestradiol-induced cell death in osteosarcoma cells is preceded by cell cycle arrest

JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2008
Avudaiappan Maran
Abstract 2-Methoxyestradiol (2-ME), a naturally occurring mammalian metabolite of 17,-Estradiol (E2), induces cell death in osteosarcoma cells. To further understand the molecular mechanisms of action, we have investigated cell cycle progression in 2-ME-treated human osteosarcoma (MG63, SaOS-2 and LM8) cells. At 5 µM, 2-ME induced growth arrest by inducing a block in cell cycle; 2-ME-treatment resulted in 2-fold increases in G1 phase cells and a decrease in S phase cells in MG63 and SaOS-2 osteosarcoma cell lines, compared to the appropriate vehicle controls. 2-ME-treatment induced a threefold increase in the G2 phase in LM8 osteosarcoma cells. The results demonstrated steroid specificity, as the tumorigenic metabolite, 16,-hydroxyestradiol (16-OHE), did not have any effect on cell cycle progression in osteosarcoma cells. The cell cycle arrest coincided with an increase in expression of the cell cycle markers p21, p27 and p53 proteins in 2-ME-treated osteosarcoma cells. Also, MG63 cells, transiently transfected with cDNA for a ,loss of function mutant' RNA-dependent protein kinase (PKR) protein, were resistant to 2-ME-induced cell cycle arrest. These results suggest that 2-ME works in concert with factors regulating cell cycle progression, and cell cycle arrest precedes cell death in 2-ME-treated osteosarcoma cells. J. Cell. Biochem. 104: 1937,1945, 2008. © 2008 Wiley-Liss, Inc. [source]

Effect of ketoprofen in topical formulation on vascular endothelial growth factor expression and tumor growth in nude mice with osteosarcoma

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2004
Kenshi Sakayama
Abstract OST cells, a low metastatic cell line established from human osteosarcoma, were inoculated under the periosteum of the ossa cranii of nude mice. Four weeks later, tumors were percutaneously treated for an additional 4 weeks with a patch containing either placebo or ketoprofen (KP). In the placebo group, OST cells formed osteoid and invaded the cranial bone. Tumor mass weighed 3.54 g. Approximately 85% of cells within the tumor expressed proliferating cell nuclear antigen (PCNA), indicating that they were proliferating with a high mitotic activity. Many feeder vessels were located within the tumor. The majority of tumor cells expressed intensely vascular endothelial growth factor (VEGF). In the KP group, invasion of OST cells into the cranial bone was suppressed and the tumor mass was 47% of that of the placebo group. Approximately 65% of cells within the tumor were PCNA-negative, indicating that their growth was arrested. There were considerably fewer feeder vessels within the tumor in the KP group than in the placebo group. Only a small number of cells expressed VEGF. Based on these findings, we concluded that topical administration of KP to nude mice with osteosarcoma inhibited VEGF expression, reduced the development of feeder vessels for supply of nutrients and oxygen, and suppressed tumor growth. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]

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

PATHOLOGY INTERNATIONAL, Issue 2 2005
Toshiaki Hitora
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. [source]

The Aberrant Expressions of Nuclear Matrix Proteins During the Apoptosis of Human Osteosarcoma Cells

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010
Zhen-Li Zhao
Abstract The objective of this study was to investigate altered expressions of nuclear matrix proteins (NMPs) of human osteosarcoma (OS) MG-63 cells during curcumin-induced apoptosis of human OS MG-63 cells. MG-63 cells were cultured with curcumin (7.5 mg/L) for 72 hr. Morphological alterations of cells were captured using light microscopy and transmission electron microscopy, and cell cycle distribution was estimated by flow cytometry. NMPs were selectively extracted and subjected to two-dimensional gel electrophoresis (2-DE) analysis. Western blots were performed to determine changes in the expression levels of specific NMPs. The results demonstrated that typical characteristics of apoptosis were observed. Cellular chromatin agglutinated, cell nuclei condensed, and apoptotic bodies were formed after treatment with curcumin. The 2-DE results displayed 27 NMPs, 21 of which were identified to have change in expression levels significantly during apoptosis. The altered expressions of three of these NMPs (nucleophosmin, prohibitin, and vimentin) were further confirmed by immunoblotting. These findings indicated that the apoptosis of MG-63 cells was accompanied by the expression alteration of NMPs. Our results might help to reveal the relationship between NMPs and the regulation of gene expression in the process of apoptosis, as well as provide the basic concepts for future studies on the mechanisms of apoptosis and the therapy for bone diseases. Anat Rec, 2010. © 2010 Wiley-Liss, Inc. [source]

Mitotic arrest defective protein 2 expression abnormality and its clinicopathologic significance in human osteosarcoma

APMIS, Issue 3 2010
LING YU
Yu L, Guo W-C, Zhao S-H, Tang J, Chen J-L. Mitotic arrest defective protein 2 expression abnormality and its clinicopathologic significance in human osteosarcoma. APMIS 2010; 118: 222,29. Osteosarcoma is the most common primary malignancy of bone. Overexpression of mitotic arrest defective protein 2 (MAD2) is found in many human neoplasms, but its role in the oncogenesis of osteosarcoma is an untouched topic. The objective of this research was to observe the expression of MAD2 in human osteosarcoma and explore its clinicopathologic significance. MAD2 expression was analyzed in 48 primary osteosarcoma cases (19 osteoblastic osteosarcomas, 17 chondroblastic osteosarcomas and 12 fibroblastic osteosarcomas) using immunohistochemistry. A total of 20 normal bone specimens formed a control group. MAD2 was commonly overexpressed in human osteosarcoma. Immunopositivity was higher in tumors with lower differentiation and higher clinical stage. Increased expression of MAD2 was associated with earlier metastasis and poorer survival. Our findings provide evidence that MAD2 contributes to the pathogenesis and development of human osteosarcoma, Testing may have a clinical role in predicting prognosis, selecting appropriate chemotherapeutic strategies and providing novel strategies for osteosarcoma therapy. [source]

Immunohistochemical profile of ephrin A4 expression in human osteosarcoma

APMIS, Issue 4 2009
ASMAA GABER ABDOU
Ephrin receptors and ephrin ligands constitute one of the largest groups of tyrosine kinases. The division of ephrin receptors into type A or type B is determined by their ligand-binding specificities. Ephrin A4 as a ligand has a broad capacity to bind and stimulate different subtypes of ephrin A receptors. Little is known about the role of ephrins generally and ephrin A4 particularly in osteosarcoma. Ephrin A4 was immunohistochemically assessed on archival material from 46 primary osteosarcoma cases, 10 metastatic pulmonary lesions and 20 normal control bone specimens. Ephrin A4 was expressed in 100% of normal bone specimens, in 84.4% of primary osteosarcoma cases and in all metastatic pulmonary lesions. Cytoplasmic and nucleocytoplasmic patterns of ephrin A4 immunoreactivity were observed, with the predominance of the latter pattern in normal bone (100%), and in 43.5% of primary osteosarcoma cases, which showed a higher intensity of expression compared with normal bone (p<0.05). The cytoplasmic pattern is the only staining pattern seen in metastatic cases, which may suggest its role in enhancement of invasion and metastasis. The differences in the distribution of the two patterns of ephrin A4 may indicate a different biological activity of this molecule depending on its localization. The nuclear localization of ephrin A4 requires further investigation to clarify the mechanism and the significance of the nuclear trafficking of ephrin A4. [source]

Sex steroid receptors expression and hormone-induced cell proliferation in human osteosarcoma

CANCER SCIENCE, Issue 3 2008
Osamu Dohi
Sex steroid receptors including estrogen receptors (ER), progesterone receptors (PR), and androgen receptors (AR) have been sporadically reported in human osteosarcoma or its cell lines. Therefore, sex steroids have been considered to play some roles in human osteosarcoma, but no systematic and detailed studies regarding the correlation between the status of these receptors in sarcoma cells and clinicopathological parameters have been reported. We examined the existence of ER, PR and AR in 28 cases of osteosarcoma using immunohistochemistry. We then characterized the potential influence of sex steroids on cell proliferation of osteosarcoma cells using MG-63 human osteosarcoma cell line, which expressed all of these receptors. ER-, and PR were detected in the great majority of the cases (23 and 24 cases, respectively) but ER-, and aromatase were not detected in all the cases, and AR was detected only in eight cases. There was a significant positive correlation between ER-, and Ki-67 (MIB1) labeling indexes. The absence of aromatase in tumors also suggests the relative importance of concentrations of circulating sex steroids. Proliferation of MG-63 cells was significantly stimulated by estradiol, progesterone, and 5,-dihydrotestosterone (DHT), and was significantly suppressed by the addition of fulvestrant (ICI), mifepristone (RU), and hydroxiflutamide, blockers for ER, PR and AR, respectively. Sex steroids, particularly estrogen and progesterone, are considered to play important roles in the regulation of cell proliferation in human osteosarcoma. In addition, these data suggest the potential for a novel endocrine therapy in osteosarcoma using clinically available inhibitors of progesterone and estrogen actions. (Cancer Sci 2008; 99: 518,523) [source]