title: Tumor necrosis factor upregulates interleukin-4 receptors on murine sarcoma cells.
abstract: We have previously shown that murine solid tumor cells express high affinity IL-4 receptors (IL-4R) which are internalized after binding to ligand. In the present study, we have examined the regulation of IL-4R by TNF. We demonstrate that TNF upregulated the expression of IL-4R on murine MCA-106 sarcoma cells. Maximum upregulation of IL-4R surface expression occurred after 24 h, whereas, maximum elevation in IL-4R mRNA levels was observed after only 4 hours of TNF treatment. This increase in mRNA levels for IL-4R occurred in a dose dependent manner. As little as 0.83 ng/ml of TNF significantly upregulated mRNA levels, whereas maximum effect was obtained with 83 ng/ml TNF. IL-4 receptor density was increased in response to TNF, no effect on IL-4R affinity was observed. Cycloheximide and Actinomycin D treatment decreased the surface expression of IL-4R by 50% in about 2 h and 7 h, respectively, in both TNF treated and untreated cells indicating the half life for the IL-4R protein expression. These studies may help understand the mechanism of cytokine interaction on tumor cells.
authors.affiliation: Laboratory of Molecular Tumor Biology, FDA, Bethesda, MD 20892.
authors.forename: R K
authors.initials: RK
authors.lastname: Puri
authors.forename: P
authors.initials: P
authors.lastname: Leland
mesh_terms: D000818:Animals; D002460:Cell Line; D003513:Cycloheximide / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D015847:Interleukin-4 / Q000378:metabolism*; D007700:Kinetics; D051379:Mice; D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D012513:Sarcoma, Experimental / Q000378:metabolism; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D019948:Receptors, Interleukin-4; D011975:Receptors, Mitogen; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D003513:Cycloheximide