This observation suggests that the induction of neoplastic transformation by the FBJ murine osteosarcoma virus may require the expression of the fos gene product at high levels in an inappropriate cell type.
Structure of the FBJ murine osteosarcoma virus genome: molecular cloning of its associated helper virus and the cellular homolog of the v-fos gene from mouse and human cells.
These molecules are able to interact and induce tyrosine-specific phosphorylation and early actin reorganization in the osteosarcoma cells, effects similar to those that PDGF induces in normal responsive cells.
A factor that promotes the growth of certain B cell hybridomas and of plasmacytomas is shown to be produced by normal human fibroblasts and by a line of human osteosarcoma cells (MG-63) after treatment with IL-1 or TNF.
We recently reported that the steroid hormone, 1 alpha,25-dihydroxyvitamin D3 (1,25-(OH)2D3) can inhibit growth, alter morphology, and increase cell associated and medium concentrations of fibronectin (FN) in MG-63 human osteosarcoma cells (Franceschi, R. T., James, W., and Zerlauth, G. (1985) J.Cell.Physiol.123, 401-409).
MG-63 human osteosarcoma cells were selected for attachment and growth in the presence of increasing concentrations of a synthetic peptide containing the cell attachment-promoting Arg-Gly-Asp sequence derived from the cell-binding region of fibronectin.
A factor that promotes the growth of certain B cell hybridomas and of plasmacytomas is shown to be produced by normal human fibroblasts and by a line of human osteosarcoma cells (MG-63) after treatment with IL-1 or TNF.
In spite of an increased number of apparently normal chromosomes #13, a 50% reduction in esterase D activity in osteosarcoma cells from the retinoblastoma patient was observed.
We used human oncogene DNA to transform the nontumorigenic, revertant, human osteosarcoma cell line HOS TE-85 clone 5 (ATCC CRL 1543) to tumorigenicity in athymic nude mice with latency periods as short as 3 weeks.
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.
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.
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.
The converse experiment, in which in vitro-translated E1b 58-kDa protein was mixed with lysates of osteosarcoma cells, showed little or no p53-E1b 58-kDa protein association, even though the in vitro E1b 58-kDa protein could associate stably with p53 from cells containing endogenous p53-E1b 58-kDa protein complex.
Recombinant human IL-1 beta inhibits human osteosarcoma cell proliferation, stimulates integrin expression, and induces alkaline phosphatase activity, a marker of osteoinductive and osteoblastic phenotype.
These data indicate that the beta 1 integrin family of cell surface receptors is a target for regulation by IL-1 beta, which also regulates cell proliferation and the expression of the osteoblastic phenotype in human osteosarcoma cells.