Downregulation of protein tyrosine phosphatase PTPL1 alters cell cycle and upregulates invasion-related genes in prostate cancer cells

The final publication is available at link.springer.comPTPL1, a non-receptor type protein tyrosine phosphatase, has been involved in the regulation of apoptosis and invasiveness of various tumour cell types, but its role in prostate cancer remained to be investigated. We report here that downregulation of PTPL1 by small interfering RNA in PC3 cells decreases cell proliferation and concomitantly reduces the expression of cell cycle-related proteins such as cyclins E and B1, PCNA, PTTG1 and phospho-histone H3. PTPL1 downregulation also increases the invasion ability of PC3 cells through Matrigel coated membranes. cDNA array of PTPL1-silenced PC3 cells versus control cells showed an upregulation of invasion-related genes such as uPA, uPAR, tPA, PAI-1, integrin α6 and osteopontin. This increased expression was also confirmed in PTPL1-silenced DU145 prostate cancer cells by quantitative real time PCR and western blot. These findings suggest that PTPL1 is an important mediator of central cellular processes such as proliferation and invasion. © 2012 Springer Science+Business Media B.V.This work was supported by Grants from the Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III, Spain (FIS PI10/02026 and SAF2008-05046-C02-02), ISCIIIRETIC-RD06/0020-FEDER, Consejería de Salud (PI-2009-0589, AI-2010-003 to M.A.J.), and Consejería de Innovación, Ciencia y Empresa (CTS-6243), Junta de Andalucía (06/189, PI-2009-0589, and AI-2010-003 to M. A. J.). C. C. was supported by a pre-doctoral Grant from the Spanish Ministerio de Educación (F.P.I.: BES200612419) co-financiated by Fondo Social Europeo. C. S. was supported by a contract from Instituto de Salud Carlos III/FIS and Fundación Progreso y Salud, Consejería de Salud, Junta de Andalucía, Miguel Servet Program.Peer Reviewe