Ovarian cancer is the fifth leading cause of female death globally due to its low survival rates. Thus, improved approaches for ovarian cancer detection are urgently needed. MicroRNAs as a new class of biomarkers have been explored in recent studies. This study was trying to identify and validate the two kinds of serum microRNA (miR-200c and miR-141) as biomarkers for ovarian cancer. We extracted serum samples from 74 epithelial ovarian cancer patients, 19 borderline ovarian cancer, and 50 healthy controls. Relative expression of these miRNA markers were measured by quantificational real-time polymerase chain reaction assay (qRT-PCR). Receiver operating characteristics (ROC) and area under the ROC curve (AUC) were used to validate the diagnostic value of miR-200c and miR-141. Kaplan-Meier curve and the log-rank test were conducted to detect the prognostic value of miR-200c and miR-141. miR-200c and miR-141 were significantly elevated in the epithelial ovarian cancer patients compared to healthy controls. The relative expression level of miR-200c showed a descending trend from early stages to advanced stages, while the level of miR-141 displayed an escalating trend. Patients with high miR-200c level achieved significantly a higher 2-year survival rate compared with the other group (P < 0.001), while low miR-141 group showed a significantly higher survival rate. The results of the current study suggested that serum miR-200c and miR-141 were able to discriminate the ovarian cancer patients from healthy controls. In addition, miR-200c and miR-141 may be predictive biomarkers for ovarian cancer prognosis. Further large-scale studies are still needed to confirm our findings.
Utilization of carbon nanodots (CNDs), newcomers to the world of carbonaceous nanomaterials, in the electrochemistry realm has rarely been reported so far. In this study, CNDs were used as immobilization supports and electron carriers to promote direct electron transfer (DET) reactions of glucose oxidase (GOx) and bilirubin oxidase (BOD). At the CNDs electrode entrapped with GOx, a high rate constant (k(s)) of 6.28 ± 0.05 s(-1) for fast DET and an apparent Michaelis-Menten constant (K(M)(app)) as low as 0.85 ± 0.03 mM for affinity to glucose were found. By taking advantage of its excellent direct bioelectrocatalytic performances to glucose oxidation, a DET-based biosensor for glucose detection ranging from 0 to 0.64 mM with a high sensitivity of 6.1 μA mM(-1) and a limit of detection (LOD) of 1.07 ± 0.03 μM (S/N = 3) was proposed. Additionally, the promoted DET of BOD immobilized on CNDs was also observed and effectively catalyzed the reduction of oxygen to water at the onset potential of +0.51 V (vs Ag/AgCl). On the basis of the facilitated DET of these two enzymes at CNDs electrodes, a mediator-free DET-type glucose/air enzymatic biofuel cell (BFC), in which CNDs electrodes entrapped with GOx and BOD were employed for oxidizing glucose at the bioanode and reducing oxygen at the biocathode, respectively, was successfully fabricated. The constructed BFC displayed an open-circuit voltage (OCV) as high as 0.93 V and a maximum power density of 40.8 μW cm(-2) at 0.41 V. These important features of CNDs have implied to be promising materials for immobilizing enzymes and efficient platforms for elaborating bioelectrochemical devices such as biosensors and BFCs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.