MOLECULAR EVENTS IN PROSTATE CANCER: LENTIVIRUS INDUCED KNOCKDOWN OF HUMAN MKP-2 ENHANCES ERK SIGNALLING IN LNCaP (AI) CELLSAbstract
The MAP kinase phosphatases regulate the magnitude and kinetics of MAP kinase signalling within the cell and as a consequence cell cycle progression and division. Therefore, these enzymes have been implicated in the regulation of number of disease conditions. One member of this family, MKP-2, has been linked to cancers of the breast and prostate. However, in human cells correlating changes in MKP-2 expression and effects upon ERK signalling, the main substrate for MKP-2 has been difficult, due to lack of convincing cellular analysis. Therefore, we utilized a novel lentivirus shRNA MKP-2 construct (L.001) to examine the consequences of knockdown on the regulation of ERK MAP kinase signalling. Infection of LNCaP AI cells with lentivirus shRNA MKP-2 reduced endogenous MKP-2 mRNA by approximately 80% in LNCaP cells. Immunofluorescent GFP labelling revealed strong cellular expression of MKP-2, approximately 70% of the cells were infected. MKP-2 knockdown reduced adenoviral induced hMKP-2 expression by approximately 50%. Both EGF and FCS induced strong but transient activation of ERK phosphorylation in LNCaP (AI), EGF giving a more rapid activation of the two agents. However, following MKP-2 knockdown ERK phosphorylation was enhanced and more sustained relative to control cells. These findings demonstrate a key role for MKP-2 in the regulation of MAP kinase (ERK) in human cancer cells and its potential role in controlling cell proliferation in cancer and metastasis.
University of Anbar, College of Pharmacy, Department of Clinical Laboratories Sciences, Anbar - Ramadi, Iraq.
14 July, 2017
13 January, 2017
27 January, 2018
01 April, 2018