title: Divergent responses to epidermal growth factor in hormone sensitive and insensitive human prostate cancer cell lines.
abstract: The present study was undertaken to compare the relationship between response to exogenous epidermal growth factor (EGF) and the expression of the EGF-receptor (EGF-R) in an androgen sensitive (LNCaP) and insensitive (DU145) prostate cancer cell line. Although both cell lines demonstrated a single EGF-R binding site of similar high affinities (mean dissociation constant (Kd) +/- S.D. for DU145 = 1.0 +/- 0.6 nmol l-1; LNCaP = 2.8 +/- 2.2 nmol l-1) the number of binding sites (RT) for the hormone insensitive DU145 cells (mean +/- S.D. = 2.5 +/- 1.0 x 10(5) sites/cell) and 10-fold greater than that expressed in the androgen responsive LNCaP cell line (mean +/- S.D. = 2.0 +/- 1 x 10(4) sites/cell). Additionally exogenous EGF only minimally affected the growth and DNA synthesis of DU145 cells whereas LNCaP cells showed a significant response which was dose dependent. The autologous production of EGF-like molecules by DU145 cells is believed to reduce the cells needs for exogenous mitogens, thereby rendering the cells autostimulatory. Treatment of LNCaP cells with Mibolerone--a synthetic androgen--did not affect either the expression of the EGF receptor or the proliferative response observed with EGF. Western blot analysis, using monoclonal antibodies directed against the EGF receptor revealed a band of approximately 170 kD with DU145 cell lysates but the LNCaP EGF receptor was not detected using this technique.
authors.affiliation: University Department of Surgery, Western General Hospital, Edinburgh, UK.
authors.forename: A
authors.initials: A
authors.lastname: MacDonald
authors.forename: F K
authors.initials: FK
authors.lastname: Habib
mesh_terms: D015153:Blotting, Western; D002455:Cell Division / Q000187:drug effects; D004273:DNA, Neoplasm / Q000096:biosynthesis; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D066246:ErbB Receptors / Q000032:analysis* / Q000187:drug effects; D006801:Humans; D008297:Male; D009277:Nandrolone / Q000031:analogs & derivatives / Q000494:pharmacology; D011471:Prostatic Neoplasms / Q000378:metabolism*; D013936:Thymidine / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D004815:Epidermal Growth Factor; D009277:Nandrolone; C100075:mibolerone; D066246:ErbB Receptors; D013936:Thymidine