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)

Chemotaxis is an important step in monocyte recruitment in inflammation, wound healing, and tumor growth. We reported previously that monocyte chemotactic activity secreted by malignant cells and normal smooth muscle cells is associated with a protein or family of proteins that are related to the monocyte-specific smooth muscle cell-derived chemotactic factor (SMC-CF) (Graves, D. T., Jiang, Y. L., Williamson, M. J., and Valente, A. J. (1989) Science 245, 1490-1493). Similar monocyte chemotactic proteins (MCP-1) produced by U-105MG human glioma cells have also been identified (Yoshimura, T., Robinson, E. A., Tanaka, S., Appella, E., Kuratsu, J., and Leonard, E. J. (1989) J. Exp. Med. 169, 1449-1459). We now report that the MCP-1 gene is expressed in MG-63 human osteosarcoma and vascular smooth muscle cells and that SMC-CF antiserum specifically immunoprecipitates proteins synthesized by U-105MG glioma cells. Experiments were undertaken to elucidate the processing pathway of MCP-1/SMC-CF-like proteins in each of these cell types. These experiments demonstrate that larger MCP-1/SMC-CF-like proteins are derived from a Mr = 9000 precursor. Post-translational modification involves the addition of O-linked carbohydrates and sialic acid residues. Differences in carbohydrate processing account for the heterogeneity in MCP-1/SMC-CF-like proteins produced by different cell types. Secretion of these proteins occurs rapidly following processing events in the endoplasmic reticulum-Golgi compartment.
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PMID:Post-translational modification of a monocyte-specific chemoattractant synthesized by glioma, osteosarcoma, and vascular smooth muscle cells. 221 4

In order to elucidate the mechanism of increased alkaline phosphatase (AI-P) activity of bone origin in serum of patients with hyperthyroidism, the effects of thyroid hormone on mouse osteoblast-like cells (MC3T3-E1) were studied in vitro. Triiodo-L-thyronine (T3) and thyroxine (T4) produced a dose-dependent increase in AI-P activity in the cells at minimum concentrations of 10(-10)M T3 (free T3, 5 x 10(-12) M) and 10(-8) M T4 (free T4, 8 x 10(-11) M), respectively. Scatchard analysis revealed that MC3T3-E1 cells contained nuclear binding sites specific for T3 with an apparent Kd of 120 pM (maximum number of binding sites, approximately 2500 per cell). When cells were cultured with T3 in alpha-minimal essential medium (alpha-MEM) for a prolonged period, AI-P activity also became detectable in the conditioned medium. In contrast to rat osteosarcoma cells (ROS 17/2.8), MC3T3-E1 cell growth was inhibited by T4 in a concentration-dependent manner. These findings suggest that thyroid hormone inhibits proliferation and stimulates differentiation of mouse osteoblast-like cells. Since T3 and T4 stimulate AI-P activity not only in the cells but also in the medium, we speculate that the hyper-alkaline phosphatasia frequently seen in patients with hyperthyroid Graves' disease is partly due to a direct effect of thyroid hormone on osteoblasts or osteoblast-like cells.
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PMID:Stimulation of alkaline phosphatase activity by thyroid hormone in mouse osteoblast-like cells (MC3T3-E1): a possible mechanism of hyperalkaline phosphatasia in hyperthyroidism. 319 Dec 90

The expression of thyrotropin receptor (TSH-R) on various cells derived from bone, including osteoblast-like rat osteosarcoma cells (UMR106 cells), was investigated. TSH receptor mRNA was detected in UMR106 cells by Northern blot analysis. 125I-labeled TSH binding analysis revealed specific high- and low-affinity binding sites (association constants of 5.6 x 10(9) M(-1) and 3.0 x 10(7) M(-1), respectively) on UMR106 cells. Recombinant TSH, but not recombinant human chorionic gonadotropin, increased cyclic adenosine monophosphate (cAMP) production in a concentration-dependent manner in these cells. Furthermore, immunoglobulin Gs from patients with Graves' disease induced cAMP response in UMR106 cells, and the cAMP response index in this cell line correlated with thyroid-stimulating antibody (TSAb) activity detected by Chinese hamster ovary (CHO)-K1 cells transfected with rat TSH-R. We have also demonstrated that recombinant TSH increased cAMP production in human osteoblast-like osteosarcoma (MG63) cells and mouse primary osteoblastic cells. These results suggest that osteoblasts possess functional TSH-R and that abnormal bone metabolism in Graves' disease may be partly explained by the interaction of TSAb with TSH-R in osteoblasts in some patients.
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PMID:Expression of thyrotropin receptor on clonal osteoblast-like rat osteosarcoma cells. 984 24