Enhanced expression of vimentin in motile prostate cell lines and in poorly differentiated and metastatic prostate carcinoma.

BACKGROUND. The metastatic potential of a series of prostate cell lines was analysed bymeasuring motility and invasiveness, and further correlated to the expression of epithelialdifferentiation markers.METHODS. Invasion and motility were measured using in vitro assays. Immunohistochem-istry of cell lines and tissues was used to identify expression of cytokeratins 8 and 1, 5, 10, 14,vimentin, prostate specific antigen, prostate specific membrane antigen, androgen receptor,desmoglein, E-cadherin, b1 integrin, CD44, hmet, vinculin and actin.RESULTS. Expressionofvimentinwastheonlymarkertocorrelatewithmotility, nomarkerscorrelated to invasion. Lower vimentin expression was observed in cells with low motility(PNT2-C2) and high expression in cells with high motility (P4E6, PNT1a, PC-3). Vimentinexpression was not detected in well differentiated tumours, moderately differentiated tumorscontained vimentin positive cells (1/9 bone scan negative, 2/5 bone scan positive), but themajority of poorly differentiated cancers (4/11 bone scan negative, 9/14 bone scan positive)and bone metastases (7/8) had high vimentin expression in tumor cells.CONCLUSIONS. Motile prostate cancer cell lines express vimentin. In tissue sections, thepresence of vimentin positive tumour cells correlated positively to poorly differentiatedcancersandthepresenceofbonemetastases. Prostate52:253–263,2002.