title: VIP induces NF-κB1-nuclear localisation through different signalling pathways in human tumour and non-tumour prostate cells.
abstract: The nuclear factor κB (NF-κB) is a powerful activator of angiogenesis, invasion and metastasis. Transactivation and nuclear localisation of NF-κB is an index of recurrence in prostate cancer. Vasoactive intestinal peptide (VIP) exerts similar effects in prostate cancer models involving increased expression of vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) which are related to NF-κB transactivation. Here we studied differential mechanisms of VIP-induced NF-κB transactivation in non-tumour RWPE-1 and tumour LNCaP and PC3 human prostate epithelial cells. Immunofluorescence studies showed that VIP increases translocation of the p50 subunit of NF-κB1 to the nucleus, an effect that was inhibited by curcumin. The signalling transduction pathways involved are different depending on cell transformation degree. In control cells (RWPE1), the effect is mediated by protein kinase A (PKA) activation and does not implicate extracellular signal-regulated kinase (ERK) or phosphoinositide 3-kinase (PI3-K) pathways whereas the opposite is true in tumour LNCaP and PC3 cells. Exchange protein directly activated by cAMP (EPAC) pathway is involved in transformed cells but not in control cells. Curcumin blocks the activating effect of VIP on COX-2 promoter/prostaglandin E2 (PGE2) production and VEGF expression and secretion. The study incorporates direct observation on COX-2 promoter and suggests that VIP effect on VEGF may be indirectly mediated by PGE2 after being synthesised by COX-2, thus amplifying the initial signal. We show that the signalling involved in VIP effects on VEGF is cAMP/PKA in non-tumour cells and cAMP/EPAC/ERK/PI3K in tumour cells which coincides with pathways mediating p50 nuclear translocation. Thus, VIP appears to use different pathways for NF-κB1 (p50) transactivation in prostate epithelial cells depending on whether they are transformed or not. Transformed cells depend on pro-survival and pro-proliferative signalling pathways involving ERK, PI3-K and cAMP/EPAC which supports the potential therapeutic value of these targets in prostate cancer.
authors.affiliation: Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Fernández-Martínez
authors.affiliation: Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain.
authors.forename: María J
authors.initials: MJ
authors.lastname: Carmena
authors.affiliation: Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Bajo
authors.affiliation: Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Vacas
authors.affiliation: Department of Surgery and Medical and Social Sciences, University of Alcalá, 28871 Alcalá de Henares, Spain; Department of Urology, Príncipe de Asturias Hospital, 28871 Alcalá de Henares, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Sánchez-Chapado
authors.affiliation: Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain. Electronic address: juancarlos.prieto@uah.es.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Prieto
mesh_terms: D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D003474:Curcumin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D006801:Humans; D008297:Male; D052002:NF-kappa B p50 Subunit / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011467:Prostate / Q000166:cytology / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology; D018005:Receptors, Vasoactive Intestinal Peptide / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D015533:Transcriptional Activation / Q000187:drug effects; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
chemical_list: D020662:Guanine Nucleotide Exchange Factors; D052002:NF-kappa B p50 Subunit; C116122:RAPGEF3 protein, human; D018005:Receptors, Vasoactive Intestinal Peptide; D042461:Vascular Endothelial Growth Factor A; D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP; D051546:Cyclooxygenase 2; D019869:Phosphatidylinositol 3-Kinases; D017868:Cyclic AMP-Dependent Protein Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; D003474:Curcumin; D015232:Dinoprostone
keywords: NF-κB; PI3-K; Tumour prostate cells; VIP; cAMP