Heparin-binding growth factor gene expression and receptor characteristics in normal rat prostate and two transplantable rat prostate tumors.
Heparin-binding polypeptide growth factors (HBGF) are essential mitogens for isolated prostate cells. HBGF type one (HBGF-1) mRNA was expressed specifically in the epithelial cells of prostates from normal 6- to 8-week-old rats. Expression declined significantly at 14 weeks and was undetectable in 35-week-old animals. Slow-growing, androgen-responsive, nonmetastatic Dunning R3327PAP tumors, which are composed of a well-defined epithelium and stroma, expressed HBGF-1 mRNA constitutively in specifically the mesenchymal cells. A rapid-growing, androgen-independent, metastatic variant (Dunning R3327AT-3), which was composed of a single clonogenic cell type, expressed both HBGF-1 and HBGF type two (HBGF-2) mRNA. HBGF activity in the extracts of normal and tumor tissues correlated with mRNA levels. Epithelial cells from the R3327PAP tumor and the single cell type that composed the R3327AT-3 tumor exhibited alterations in HBGF receptor characteristics that correlated with increased sensitivity to mitogenic effects of HBGF. The results suggest that alterations in HBGF gene expression in both prostate epithelial and mesenchymal cells and in properties of the receptor in specifically epithelial cells may contribute to differential growth rates and malignancy of different prostatic tumors.
Mansson
P E
PE
W. Alton Jones Cell Science Center, Inc., Lake Placid, New York 12946.
Adams
P
P
Kan
M
M
McKeehan
W L
WL
D000818:Animals; D004247:DNA / Q000032:analysis; D016220:Fibroblast Growth Factor 1; D006133:Growth Substances / Q000032:analysis / Q000235:genetics*; D006493:Heparin / Q000032:analysis / Q000235:genetics*; D008297:Male; D008934:Mitogens / Q000494:pharmacology; D008970:Molecular Weight; D009368:Neoplasm Transplantation; D011467:Prostate / Q000032:analysis*; D011471:Prostatic Neoplasms / Q000032:analysis*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011975:Receptors, Mitogen / Q000032:analysis*; D040262:Receptors, Vascular Endothelial Growth Factor; D014407:Tumor Cells, Cultured
D006133:Growth Substances; D008934:Mitogens; D012333:RNA, Messenger; D011975:Receptors, Mitogen; D016220:Fibroblast Growth Factor 1; D006493:Heparin; D004247:DNA; D040262:Receptors, Vascular Endothelial Growth Factor