Steroid hormone regulation and prognostic value of the human kallikrein gene 14 in ovarian cancer.

To study KLK14 gene expression in endocrine-related cancers, we studied its hormonal regulation in breast and ovarian cancer cell lines. Our kinetic and blocking experiments suggest that this up-regulation is mediated through the androgen receptor. We then studied the expression of KLK14 by quantitative reverse transcriptase-polymerase chain reaction in 155 consecutive ovarian tumors and correlated these findings with clinicopathologic parameters, response to chemotherapy, and survival. A stepwise reduction was observed in the levels of KLK14 messenger RNA in normal, benign, and cancerous tissues (P < .001). Expression levels were significantly higher in patients with early stage disease and optimal debulking and in patients who responded to chemotherapy. Kaplan-Meier survival curves demonstrated longer progression-free and overall survival in patients with KLK14-positive tumors than in patients with KLK14-negative tumors (P < .001). When all other prognostic variables were controlled in the multivariate analysis, KLK14 retained its prognostic significance (progression-free and overall survival, respectively, hazard ratios, 0.43 and 0.53; P = .027 and .014). A weak negative correlation was found between KLK14 expression and serum CA-125. KLK14 is a new, independent, and favorable prognostic marker for ovarian cancer.