Cytoplasmic retention of protein tyrosine kinase 6 promotes growth of prostate tumor cells.

ABSTRACT: Protein tyrosine kinase 6 (PTK6) is an intracellular tyrosine kinase that is nuclear in epithelial cells of the normal prostate, but cytoplasmic in prostate tumors and in the PC3 prostate tumor cell line. The impact of altered PTK6 intracellular localization in prostate tumor cells has not been extensively explored. Knockdown of endogenous cytoplasmic PTK6 resulted in decreased PC3 cell proliferation and colony formation, suggesting that cytoplasmic PTK6 stimulates oncogenic pathways. In contrast, reintroduction of PTK6 into nuclei of PC3 cells had a negative effect on growth. Enhanced tyrosine phosphorylation of the PTK6 substrate Sam68 was detected in cells expressing nuclear-targeted PTK6. We found that mechanisms regulating nuclear localization of PTK6 are intact in PC3 cells. Transien

SUBMITTER: Brauer PM 

PROVIDER: S-EPMC3055202 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature