Circulating biomarker tissue kallikrein-related peptidase KLK5 impacts ovarian cancer patients' survival.

5088 Background: KLK5 is a secreted serine protease expressed in hormonally regulated tissues, including the ovary. KLK5 is almost undetectable in the serum of normal individuals and in patients with malignancies other than that of the ovary or the breast. Besides that, high levels of KLK5 were detected in the ascitic fluid obtained from advanced ovarian cancer patients. KLK5 expression in ovarian cancer tissues was also demonstrated at the gene and the protein level. Thus, KLK5 appears to be a promising disease forecast marker for predicting the clinical course of ovarian cancer. Methods: 52 patients with histologically confirmed primary ovarian carcinoma FIGO I-IV were enrolled in this study. Patients were treated by primary cytoreductive surgery followed by platinum-containing chemotherapy. Antigen concentration of KLK5 in serum and ascitic fluid was quantified by ELISA. No cross- reactivity of the KLK5-ELISA with the other 14 members of the kallikrein-like peptidase family was observed. For comparison...