A role for heparan sulfate in androgen-induced deoxyribonucleic acid synthesis of mouse mammary carcinoma (Shionogi carcinoma 115)-derived SC-3 cells.
In response to androgen stimuli, SC-3 cells cloned from mouse mammary carcinoma (Shionogi carcinoma 115) secrete heparin-binding growth factor, which is able to bind to fibroblast growth factor (FGF) receptor, ultimately resulting in SC-3 cell proliferation. A role for glycosaminoglycan in the process of this androgen-induced autocrine loop was examined. When quiescent SC-3 cells were stimulated with testosterone, enhanced DNA synthesis was demonstrated even at the early phase (12-24 h) of stimulation. During this early period, autocrine growth-promoting activity was found to be associated with cell surface and extracellular matrix, but not to be present in the conditioned medium. This bound form of growth-promoting activity was able to be extracted with 2 M NaCl (pH 7.5) and absorbed onto a heparin-Sepharose affinity column, from which it was eluted at a concentration of 1.1-1.3 M NaCl. Extracted growth factor, whose activity was partially blocked by anti-basic FGF antibody, up-regulated the expression of FGF receptor-1 mRNA. These characteristics were similar to those of a soluble form of SC-3-derived growth factor previously reported from our laboratory. Androgen-induced enhancement of DNA synthesis was inhibited by simultaneous treatment of SC-3 cells with 10 mIU/ml heparitinase or 25 mM sodium chlorate (an inhibitor of phosphoadenosine sulfate synthesis). However, chlorate treatment did not affect the synthesis and distribution of androgen-induced growth factor, suggesting that the response of chlorate-treated cells to this growth factor was impaired. These results indicate that heparan sulfate has important roles in concentrating androgen-induced heparin-binding growth factor on or very close to the cell surface and in potentiating its bioactivity.
Sumitani
S
S
Department of Internal Medicine III, Osaka University Hospital, Japan.
Kasayama
S
S
Sato
B
B
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002704:Chlorates / Q000494:pharmacology; D002846:Chromatography, Affinity; D002999:Clone Cells; D004261:DNA Replication / Q000187:drug effects*; D004273:DNA, Neoplasm / Q000096:biosynthesis*; D006025:Glycosaminoglycans / Q000302:isolation & purification / Q000378:metabolism; D006133:Growth Substances / Q000302:isolation & purification / Q000502:physiology*; D006497:Heparan Sulfate / Q000502:physiology*; D007700:Kinetics; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism*; D051379:Mice; D011133:Polysaccharide-Lyases / Q000494:pharmacology*; D013431:Sulfates / Q000378:metabolism; D013462:Sulfur Radioisotopes; D013739:Testosterone / Q000494:pharmacology*; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium; D014407:Tumor Cells, Cultured
D002704:Chlorates; D004273:DNA, Neoplasm; D006025:Glycosaminoglycans; D006133:Growth Substances; D006497:Heparan Sulfate; D011133:Polysaccharide-Lyases; D013431:Sulfates; D013462:Sulfur Radioisotopes; D013739:Testosterone; D013936:Thymidine; D014316:Tritium; C021349:heparitinsulfate lyase; C032706:sodium chlorate