Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Normal osteoblasts from newborn rat calvaria and human osteosarcoma (Saos-2) cells express IGFBP-5 mRNA. IGF I increases IGFBP-5 mRNA levels in both cell types, whereas retinoic acid stimulates IGFBP-5 mRNA expression in calvaria but suppresses it in Saos-2 cells. IGFBP-5 mRNA expression is stimulated in normal bone cells by parathyroid hormone. 30 nM IGFBP-5 stimulates 3H-thymidine incorporation in calvaria (which produce IGF I contributing to basal proliferation in serum-free medium) but not in Saos-2 cells which produce little IGF I and IGF II. Among the 5 rhIGFBPs tested (IGFBP-2 to -6), only IGFBP-5 stimulates DNA synthesis in calvaria cells, and only IGFBP-6 in Saos-2 cells. RhIGFBP-5 displays a short half-life (approximately 30 min) in serum-free medium of calvaria cells and a long half-life (approximately 15 h) in the medium of Saos-2 cells. Fragments of 20 and 14 kDa accumulate in the media of both cell types. Intact (31 kDa) IGFBP-5 is associated and remains with the extracellular matrix of mature calvaria osteoblasts but not of Saos-2 cells. Among the IGFBPs produced IGFBP-5 is unique with regard to its marked affinity to matrix of normal bone cells, its short half-life when released, and its stimulatory effects on DNA synthesis.
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PMID:Expression, effects, and fate of IGFBP-5 are different in normal and malignant osteoblastic cells. 881 58

Bone only metastasis in patients with estrogen receptor (ER) positive breast cancer reported to have favorable response to chemotherapy, favorable prognosis, and an "indolent" course. Therefore, we assessed the ability of MG-63 osteoblast-like human osteosarcoma cells (MG-63 cells) and MG-63 conditioned media (CM) to influence adriamycin-cytotoxicity of ER-positive MCF-7 human breast cancer cells. Estradiol (E2; 100 nM) increased the distribution at S and G2/M phases in the cell cycle and stimulated the growth of MCF-7 cells. Adriamycin (100 nM) inhibited the growth and arrested the MCF-7 cells supplemented with or without 100 nM of estradiol [(-E2) and (+E2) MCF-7 cultures] at G2/M phase in the cell cycle. In addition, adriamycin (100 nM) increased the distribution at G1/G0 phase in the cell cycle of (+E2) MCF-7 cultures. Adriamycin (100 nM and 10 microM) did not induce apoptosis of MCF-7 cells as assessed by flow cytometry and analysis of DNA fragmentation on simple agarose gel. Exogenous insulin-like growth factor I (IGF I) stimulated while transforming growth factor beta 1 (TGF beta 1) and MG-63 CM inhibited the growth of MCF-7 cells. Furthermore, MG-63 CM and TGF beta 1 enhanced while exogenous IGF I reversed adriamycin (100 nM)-cytostasis of MCF-7 cells. These data suggested that osteoblastic CM contained growth factors, such as TGF beta 1 capable of enhancing adriamycin-cytostasis, in vitro. Conceivably, these osteoblast-derived "enhancers" of chemotherapy-cytostasis can explain the favorable prognosis and "indolent" course of ER-positive breast cancer patients with bone only metastasis.
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PMID:Osteoblast-derived growth factors enhance adriamycin-cytostasis of MCF-7 human breast cancer cells. 989 70

Insulin-like growth factor (IGF) I is a potent mitogen for human osteosarcoma cells such as the Saos-2/B-10 cell line. IGF binding proteins (IGFBPs) prevent stimulation of DNA synthesis by IGFs. In contrast to recombinant human (rh) IGFBP-2, -3, -4, and -5, 10-100 nM rhIGFBP-6 stimulated [(3)H]thymidine incorporation into DNA and multiplication of Saos-2/B-10 cells. Upon withdrawal of serum, 30 nM IGFBP-6 also decreased apoptosis (within 4 h) and increased protein content and sodium-dependent phosphate uptake (within 24 h), but less potently than IGF I. (125)I-labeled rhIGFBP-6 did not bind to the cells, and cold IGFBP-6 did not affect (125)I-labeled IGF I binding. Production of IGF I, IGF II, and IGFBP-6 by the cells or significant degradation of rhIGFBP-6 could not be detected within 24 h of incubation. Thus, among the rhIGFBPs tested, rhIGFBP-6 is unique in stimulating osteosarcoma cell growth. Furthermore, it has an antiapoptotic effect.
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PMID:Mitogenic and antiapoptotic effects of insulin-like growth factor binding protein-6 in the human osteoblastic osteosarcoma cell line Saos-2/B-10. 1051 58

Studies in osteosarcoma over the past 40 years have led to a steady improvement in the overall outcome of patients with osteosarcoma. In the year 2008, we can expect greater than 60% overall survival for newly diagnosed non-metastatic appendicular osteosarcoma. However, to achieve this current outcome, many patients are treated with aggressive cytotoxic chemotherapy and ultimately are not cured, and some patients who would be curable even without this aggressive approach are likely treated and cured. And finally, patients presenting with metastatic disease and those whose tumors recur after standard approaches continue to do very poorly. We believe that in order to continue to make progress in the treatment of this disease, we must achieve two main objectives. Firstly, we must find biomarkers that prospectively and accurately identify newly diagnosed non-metastatic patients who will not be cured with current modalities. We hope that the achievement of this goal will allow for innovative clinical studies in this high-risk population while not jeopardizing those patients who currently are cured using the available treatment approaches, and ultimately accelerate progress toward curing more patients. Secondly, we must develop entirely new approaches to the treatment of metastatic and recurrent osteosarcoma. Our approach has been to develop models of highly aggressive and less aggressive osteosarcoma, and to use these models to identify genetic alterations and signaling pathways that distinguish the two phenotypic behaviors. We have identified plasma membrane-cytoskeletal linker protein, ezrin, as one pathway that identifies aggressive biological behavior in mouse and dog osteosarcoma. Using ezrin as the initial discriminator, we have high ezrin expression to activation of mTOR signaling, suggesting a possible novel target for therapy of aggressive osteosarcoma. We have also linked beta4 integrin signaling to metastatic behavior that also appears to be linked to mTOR signaling. Most recently, we have identified a critical relationship between mTOR signaling and the IGF I signaling pathway that may help point the way to combination targeting therapy aimed at blocking both mTOR and IGF signaling in these tumors. Finally, we have proposed a novel clinical trial design to begin to test agents targeted at recurrent, metastatic disease, and this also will be discussed.
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PMID:Strategies to explore new approaches in the investigation and treatment of osteosarcoma. 2021 13