YKL-40 tissue expression andplasma levels in patients with ovarian cancer.
YKL-40 (chitinase-3-like-1) is a member of "mammalian chitinase-like proteins". The protein is expressed in many types of cancer cells and the highest plasma YKL-40 levels have been found in patients with metastatic disease, short recurrence/progression-free intervals, and short overall survival.
The aim of the study was to determine the expression of YKL-40 in tumor tissue and plasma in patients with borderline ovarian tumor or epithelial ovarian cancer (OC), and investigate prognostic value of this marker.
Methods: YKL-40 protein expression was determined by immunohistochemistry in tissue arrays from 181 borderline tumors and 473 OC.
Plasma YKL-40 was determined by ELISA in preoperative samples from 19 patients with borderline tumor and 76 OC patients.
Results: YKL-40 protein expression was found in cancer cells, tumor associated macrophages, neutrophils and mast cells.
The tumor cell expression was higher in OC than in borderline tumors (p=0.001), and associated with FIGO stage (p<0.0001) and histological subtype (p=0.0009). Positive YKL-40 expression (>5% staining) was not associated with reduced survival.
Plasma YKL-40 was also higher in patients with OC than in patients with borderline tumors (p<0.0001), and it was positively correlated to serum CA-125 (p<0.0001) and FIGO stage (p=0.0001). Univariate Cox analysis of plasma YKL-40 showed association with overall survival (p<0.0001).
Multivariate Cox analysis, including plasma YKL-40, serum CA125, FIGO stage, age and radicality after primary surgery as variables, showed that elevated plasma YKL-40 was associated with a shorter survival (HR=2.13, 95% CI: 1.40-3.25, p=0.0004).
Conclusions: YKL-40 in OC tissue and plasma are related to stage and histology, but only plasma YKL-40 is a prognostic biomarker in patients with OC.
Published on: 2009-01-09