Background: Insulin-like growth factor binding protein-3 (IGFBP-3) is a glycoprotein with specific binding affinity to peptide hormones insulin-like growth factors (IGFs) which are potent mitogens for a variety of cells. IGFBP-3 can inhibit the activities of IGFs by interfering with the interaction between IGFs and their receptor IGF-IR. Epithelial ovarian cancer (EOC) tissues express IGFBP-3, IGFs and IGF-IR. Moreover, high levels of IGF-I and IGF-IR have been shown in epithelial ovarian cancer, and IGF-I stimulates the growth of ovarian cancer.
Methods: We measured IGFBP-3 levels in ovarian cancer tissues of 147 consecutive patients and we examined its association with clinical and pathological features of the disease and patient survival. The average age of the patients in the study was 55 years and the median follow-up time was 37 months. IGFBP-3 levels were measured in the tissue extracts by a commercial ELISA kit and non-parametric statistics and the Cox regression survival analysis were used to determine the associations of IGFBP-3 with clinical and pathologic variables as well as with patient survival.
Results: High IGFBP-3 levels resulted significantly associated with some of the favorable prognostic features of the disease, including early clinical stage (p=0.048), small size of residual tumor (p=0.007), and optimal debulking result (p=0.007). High IGFBP-3 was also associated with a significantly reduced risk for disease progression (RR=0.52, p=0.034) and we showed an inverse dose-dependent relationship between IGFBP-3 and disease progression-free survival (p=0.033). However, the association with disease progression-free survival was no longer statistically significant in a multivariate analysis. An association between IGFBP-3 and overall survival was not shown.
Conclusions: This study suggest that IGFBP-3 may play a role in the progression of epithelial ovarian cancer.