title: Osteoblast-induced EGFR/ERBB2 signaling in androgen-sensitive prostate carcinoma cells characterized by multiplex kinase activity profiling.
abstract: Bone metastases in prostate cancer are predominantly osteoblastic. To study regulatory mechanisms underlying the establishment of prostate cancer within an osteoblastic microenvironment, human androgen-sensitive prostate carcinoma cells (LNCaP) were treated with culture medium conditioned by human osteoblast-derived sarcoma cells (OHS), and activated signalling pathways in the carcinoma cells were analyzed using microarrays with tyrosine kinase substrates. Network interaction analysis of substrates with significantly increased phosphorylation levels revealed that signalling pathways mediated by EGFR and ERBB2 were activated in LNCaP cells under OHS influence but also by androgen treatment. Activation of EGFR/ERBB2 signalling was also found in LNCaP cells in cocultures with OHS cells or osteoblastic cells that had been differentiated from human mesenchymal stem cells. Our experimental data suggests osteoblast-directed induction of signalling activity via EGFR and ERBB2 in prostate carcinoma cells and may provide a rationale for the use of EGFR or ERBB2 inhibition in systemic prevention or treatment of metastatic prostate cancer in the androgen-sensitive stage of the disease.
authors.affiliation: Department of Tumor Biology, Oslo University Hospital, Montebello, 0310, Oslo, Norway.
authors.forename: Ase
authors.initials: A
authors.lastname: Bratland
authors.forename: Piet J
authors.initials: PJ
authors.lastname: Boender
authors.forename: Hanne K
authors.initials: HK
authors.lastname: Høifødt
authors.forename: Ingrid H G
authors.initials: IH
authors.lastname: Østensen
authors.forename: Rob
authors.initials: R
authors.lastname: Ruijtenbeek
authors.forename: Meng-Yu
authors.initials: MY
authors.lastname: Wang
authors.forename: Jens P
authors.initials: JP
authors.lastname: Berg
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Lilleby
authors.forename: Øystein
authors.initials: Ø
authors.lastname: Fodstad
authors.forename: Anne Hansen
authors.initials: AH
authors.lastname: Ree
mesh_terms: D000728:Androgens / Q000378:metabolism; D002277:Carcinoma / Q000188:drug therapy* / Q000378:metabolism; D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000378:metabolism*; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D010006:Osteoblasts / Q000378:metabolism*; D010766:Phosphorylation; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D012509:Sarcoma / Q000378:metabolism
chemical_list: D000728:Androgens; D066246:ErbB Receptors; D018719:Erb-b2 Receptor Tyrosine Kinases