Growth hormone affects gene expression and proliferation in human prostate cancer cells.

We previously showed that growth hormone (GH) receptors (GHR) are expressed in the most commonly studied human prostate cancer (PCa) cell lines and that GHR isoforms undergo differential, cell-type-specific hormonal regulation. We now report that human GH (hGH) can stimulate/modulate insulin-like growth factor (IGF) and β-oestradiol (E(2) ) receptor (ER(β) ) gene expressions in these cells and interact with IGF-I and E(2) to stimulate androgen-dependent LNCaP cell proliferation. We observed a cell type-dependent, differential regulation of IGF axis gene expression by GH: IGF-I was stimulated in the androgen-dependent LNCaP cells; IGF-II was stimulated in androgen-insensitive (AI) PC3 cells; the IGF-I cognate receptor, IGF-IR, was stimulated in LNCaP cells, but inhibited in PC3 cells; IGF-IIR was stimulated in both LNCaP and PC3 cells.

Regulation of growth hormone receptors in human prostate cancer cell lines.

We previously demonstrated the gene expression of two growth hormone (GH) receptor (GHR) isoforms in prostate cancer (PCa) patient tissues and human PCa cell lines. In that initial study, we characterized LNCaP cell GH binding characteristics to GHR and its activation of relevant signal transduction pathways. We now show that GH binding to GHR and GHR mRNA expression in the cell lines studied are hormonally regulated.

Growth hormone (GH) receptors in prostate cancer: gene expression in human tissues and cell lines and characterization, GH signaling and androgen receptor regulation in LNCaP cells.

Various hormones and growth factors have been implicated in progression of prostate cancer, but their role and the underlying molecular mechanism(s) involved remain poorly understood. In this study, we investigated the role of human growth hormone (GH) and its receptor (GHR) in human prostate cancer. We first demonstrated mRNA expression of GHR and of its exon 9-truncated isoform (GHR(tr)) in benign prostate hyperplasia (BPH) and prostate adenocarcinoma patient tissues, as well as in LNCaP, PC3 and DU145 human prostate cancer cell lines.