BACKGROUND: The transcriptional repressor EZH2 is implicated in control of cell 
proliferation in embryonic, immortalized and transformed cells. EZH2 expression 
in prostate cancer correlates with progression to hormone-refractory and 
metastatic disease, but it is unknown whether EZH2 plays a specific role in the 
acquisition of an advanced prostate cancer phenotype.
METHODS: Using siRNA knockdown, we investigated the role of EZH2 in maintenance 
of prostate cancer cell proliferation and invasiveness. Using LNCaP cells with 
inducible EZH2 overexpression, we investigated whether EZH2 upregulation 
promotes an aggressive phenotype.
RESULTS: Knockdown of endogenous EZH2 reduced proliferation of 
androgen-responsive and androgen-independent prostate cancer cells. EZH2 
knockdown also inhibited prostate cancer cell invasion. However, overexpression 
of EZH2 in androgen-responsive cancer cells did not appreciably affect either 
proliferation or invasiveness.
CONCLUSIONS: EZH2 promotes proliferation and invasion of prostate cancer cells, 
which can account for the correlation between EZH2 expression levels and an 
adverse prostate cancer prognosis.