Expression of fibroblast growth factor-8 in adult rat tissues and human prostate carcinoma cells.
Androgens are essential for normal prostatic and testicular function. However, paracrine and/or autocrine actions of a number of growth factors have been implicated in the function of these tissues. A recent addition to the fibroblast growth factor family, the so called androgen-induced growth factor (AIGF) or fibroblast growth factor-8 (FGF-8), has been proposed to be under strict androgen regulation and induction in the mouse mammary carcinoma cell line SC3. FGF-8, therefore, may have a local role in the prostate, which is known to be an androgen-responsive organ. This study reports, for the first time, the presence of FGF-8 mRNA in normal adult rat tissues (heart, brain, lung, kidney, testis, prostate and ovary), using an optimised reverse transcription and nested polymerase chain reaction (RT-PCR) procedure, although androgen-dependent FGF-8 expression was not demonstrated in these adult tissues. Consistent with the oncogenic characteristics of FGF-8, the corresponding mRNA was detected in the human prostate tumour cell lines LNCaP and DU145. Because the DU145 cell line is known to be androgen-independent, and the expression of FGF-8 mRNA in cultured LNCaP cells also occurred in the absence of exogenous androgens, it can be concluded that the expression of FGF-8 mRNA in these human cell lines, in the rat prostate and in other rat tissues is not under the regulation of androgens as hitherto proposed.
Schmitt
J F
JF
Institute of Reproduction and Development, Monash Medical Centre, Clayton, Victoria, Australia.
Hearn
M T
MT
Risbridger
G P
GP
D000728:Androgens / Q000502:physiology; D000818:Animals; D001483:Base Sequence; D005260:Female; D051524:Fibroblast Growth Factor 8; D005346:Fibroblast Growth Factors; D005786:Gene Expression Regulation; D006133:Growth Substances / Q000096:biosynthesis / Q000235:genetics*; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics*; D009928:Organ Specificity; D016133:Polymerase Chain Reaction / Q000379:methods; D011467:Prostate / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017422:Sequence Analysis, DNA; D013737:Testis / Q000378:metabolism; D014407:Tumor Cells, Cultured
D000728:Androgens; C496456:FGF8 protein, human; C496458:Fgf8 protein, rat; D006133:Growth Substances; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D051524:Fibroblast Growth Factor 8; D005346:Fibroblast Growth Factors