Basic And Clinical Studies Of Blood Derived Markers In Ovarian Cancer

Part Ⅰ The significance of DNA methylation of peripheral blood leukocytes in the diagnosis of ovarian cancerObjective: Ovarian cancer is one of the common malignant tumor and the most lethal cancer in women’s reproductive organs.Due to the lack of effective diagnostic indicators,about 70% of the patients were being diagnosed at late stage and the 5-year survival rate is only 20%.Therefore,early diagnosis is very important to improve patient’s survival.The aim of this study is to find DNA methylation based biomarkers which could be used for early diagnosis of ovarian cancer.Methods: We conducted a two stage epigenome-wide association study.In the first phase,the Illumina 450 K Infinium Methylation Bead Chip was used to measure genome wide methylation level of 24 patients with epithelial ovarian cancer and 24 healthy controls.Differential methylation sites between the cases and the controls were analyzed.In the second validation phase,206 epithelial ovarian cancer cases and 205 healthy controls were selected to verify the differential methylated CpG sites by Illumina Custom Vera Code Methylation Assay.The relevant genes regulated by different CpG sites were annotated and related biological signaling pathways were analyzed using DAVID software.Results: We selected 96 significantly differentially methylated CpG sites for validation and 46 CpG sites were found to be significantly correlated with ovarian cancer.A set of six CpG sites was found by the receiver operating characteristic analysis to have a prediction accuracy of 77.3% in ovarian cancer(95% CI:72.9-81.8%).Pathway analysis found that the related genes was enriched in immune system-associated signaling pathways include LYST(cg16962115,FDR=1.24E-04),CADM1(cg21933078,P=1.22E-02),and NFATC1(cg06784563,FDR=1.46E-02).In addition,we found that DNA methylation status in peripheral blood leukocytes correlated with platelet parameters/coagulation factors.Conclusion: The case-control analysis discovered a panel of epigenetic liquid biopsy markers closely associated with overall immunologic conditions and platelet parameters/coagulation systems of the patients for detection in all stages and subtypes of epithelial ovarian cancer.Part Ⅱ The significance of routine blood test in the diagnosis of ovarian cancerObjective: In the part I,we found the correlation between DNA methylation and platelet/coagulation parameters.Therefore,we hypothesis that blood cell counts may be used as a diagnosis biomarker of ovarian cancer.This study aimed to investigate the utility and importance of the various parameters of routine blood test for distinguishing benign ovarian masses from malignant.Methods: This study involved 887 epithelial ovarian cancer patients and 207 patients with benign tumor,who underwent primary surgical treatment and confirmed by pathology.The data of preoperative routine blood test,tumor biomarkers and the clinicopathological information of the patients were analyzed.Results: The area under the ROC curve of CA125 was 90.76%(95% CI: 88.64-92.88%).When CA125 combined with single inflammatory marker,the area under the ROC curve of CA125+NEUT,CA125+ WBC and CA125 +NLR were 90.82%(95% CI: 88.70-92.94%),90.82%(95% CI: 88.70-92.94%),and 90.78%(95% CI: 88.66-92.91%),respectively.In the early stage ovarian cancer,the area under the ROC curve of CA125+WBC and CA125 were 81.20%(95% CI: 77.37-85.02%)and 81.06%(95% CI: 77.22-84.89%),respectively.When CA125 combined with several inflammatory markers,the area under the ROC curve of CA125+NEUT_R+NLR+NEUT+WBC and CA125+HE4+WBC+LYMPH_R were 90.91%(95% CI: 88.80-93.03%)and 89.58%(95% CI: 85.85-93.32%),respectively,which was superior to CA125(90.76%,95% CI: 88.64-92.88%)and CA125+HE4(89.43%,95% CI: 85.68-93.18%).In the diagnosis of early ovarian cancer,the area under the ROC curve of CA125+WBC+NEUT+NLR,CA125+HE4+WBC+ LYMPH_R was 81.26%(95%CI:77.4-85.1%)and 79.5%(95% CI:73.6-85.4%)respectively,which was superior to CA125(81.06%,95% CI:77.2-84.9%)and CA125+HE4(78.88%,95% CI: 72.9-84.9%).Conclusion: This study found that the parameters of routine blood test could improve the ability of CA125 and HE4 to identify early ovarian cancer,and it will improve ovarian cancer survival rates.