Vasoactive intestinal peptide induces neuroendocrine differentiation in the LNCaP prostate cancer cell line through PKA, ERK, and PI3K

• Published in: The Prostate Vol. 63; no. 1; pp. 44 - 55
• Main Authors: Gutiérrez-Cañas, Irene, Juarranz, María G., Collado, Beatriz, Rodríguez-Henche, Nieves, Chiloeches, Antonio, Prieto, Juan C., Carmena, María J.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.04.2005; Wiley-Liss
• Subjects: Biological and medical sciences; Carcinoma, Neuroendocrine; Cell Differentiation - drug effects; Cell Line, Tumor; Cyclic AMP-Dependent Protein Kinases - metabolism; Gynecology. Andrology. Obstetrics; Humans; LNCaP; Male; Male genital diseases; MAP Kinase Signaling System - drug effects; Medical sciences; Mitogen-Activated Protein Kinase 1 - metabolism; Mitogen-Activated Protein Kinase 3 - metabolism; NE differentiation; Nephrology. Urinary tract diseases; Neuroprotective Agents - pharmacology; Phosphatidylinositol 3-Kinases - metabolism; prostate cancer; Prostatic Neoplasms; protein kinases; Tumors; Tumors of the urinary system; Urinary tract. Prostate gland; Vasoactive Intestinal Peptide - pharmacology; VIP; Andrology; Nephrology; NE differentiation; Urinary system disease; LNCaP; Prostate disease; Extracellular signal-regulated protein kinase; Enzyme; Transferases; Gynecology; Mitogen-activated protein kinase; protein kinases; Malignant tumor; 1-Phosphatidylinositol 3-kinase; Cell line; Protein kinase; Established cell line; Vasoactive intestinal peptide; Differentiation; VIP; Male genital diseases; Prostate cancer; Tumor cell
• ISSN: 0270-4137; 1097-0045
• DOI: 10.1002/pros.20173

BACKGROUND Neuroendocrine (NE) differentiation in prostate cancer has been correlated with unfavorable clinical outcome. The mechanisms by which prostate cancer acquires NE properties are poorly understood, but several signaling pathways have been proposed. We have previously observed that vasoactive intestinal peptide (VIP) stimulates cAMP production mainly through VPAC1 receptor, inducing NE differentiation in LNCaP cells. The aim of this study was to analyze the mechanisms involved in this process. METHODS Reverse transcriptase (RT)‐polymerase chain reaction (PCR), quantitative real‐time RT‐PCR, Western blotting, and immunocytochemistry were performed. RESULTS LNCaP cells produce VIP, as demonstrated by RT‐PCR and immunocytochemistry. VIP induced NE differentiation of LNCaP cells at a time as short as 1 hr of treatment, and the same occurred with the expression and secretion of neuronal‐specific enolase (NSE, a NE differentiation marker). These effects were faster than those exerted by serum‐deprivation. VIP induced extracellular signal‐regulated kinase 1 and 2 (ERK1/2) phosphorylation and NE differentiation by PKA‐dependent and independent pathways, since the PKA inhibitor H89 partially blocked VIP‐induced NE differentiation and did not affect ERK1/2 phosphorylation. mitogen‐activated protein kinase kinase (MEK) and phosphoinositide 3‐kinase (PI3K) appear to be also involved since the inhibitors PD98059 and wortmannin abolished ERK1/2 phosphorylation and decreased NE differentiation induced by VIP. Moreover, VIP activated Ras suggesting the involvement of a Ras‐dependent pathway. CONCLUSIONS VIP behaves as autocrine/paracrine factor in LNCaP cells by inducing NE differentiation through PKA, ERK1/2, and PI3K. © 2004 Wiley‐Liss, Inc.