Plasma LPA Levels And Expression Of LPA Receptors In Ovarian Epithelial Carcinoma

Objective To determine whether elevated levels of Lysophosphatidic Acid(LPA) are present in plasma from patients with ovarian epithelial carcinoma, and to evaluate whether an elevated LPA plasma level has a significant value in diagnosis of these diseases. The mRNA expression of endothelial differentiation gene-encoded G protein-coupled receptors (EdgRs) are detected in ovarian tumor and compared with plasma LPA levels to determine whether they are significantly correlated.Methods LPA were separated with lipid extraction and chromatography from 41 plasma specimens of ovarian epithelial carcinoma> 22 of ovarian epithelial benign diseases 13 of ovarian endometriotic cysts and 21 of healthy control people , then quantified with chromatometer. The plasma levels of LPA were compared with serum CA125 levels of ovarian malignant tumors and nonmalignant diseases. The RT-PCR method was used to detect the mRNA expression of Edg2 and Edg4 of LPA receptors in ovary of 24 patients with ovarian malignant tumors and 18 with ovarian nonmalignant diseases. Results Patients in the ovarian epithelial carcinoma group had significantly higher plasma LPA levels compared with the healthy control group and ovarian nonmalignant diseases group. And plasma LPA levels was more sensitive and specific to ovarian epithelial carcinoma than serum CA125 levels in our study, but there was no significant value in statistics. The expression of Edg4 in the ovarian epithelial carcinoma group was higher than that in ovarian nonmalignant diseases, while there was no distinctive expression of Edg2 between ovarianmalignant tumors and nonmalignant diseases. The overexpression of Edg4 in the ovarian epithelial carcinoma was positively correlated with the higher levels of plasma LPA, while there was no correlation between LPA and Edg2.Conclusions Plasma LPA levels was significantly elevated in the ovarian epithelial carcinoma .which might represent a potential biomarker for ovarian carcinoma. The function of LPA to ovarian cancer might be closely related to its Edg4 receptor.