The Establishment of an HE4-CLIA Method and the Combined Analysis of HE4 and CA125 in Ovarian Cancer.

Background: The human epididymal secretory protein 4 (HE4) is a novel, verified biomarker for the early diagnosis of ovarian cancer.

Methods: Magnetic beads were coated with capture antibodies and were used with acridinium ester labeled detection antibodies in a sandwich-type immunoassay. The patient's HE4 serum levels were measured simultaneously with the chemiluminescence immunoassay (CLIA) kit we developed and electrochemiluminescence immunoassay (ECLIA) kit from Roche (Mannheim, Germany). CA125 was also detected by time-resolved fluoroimmunoassay. The diagnostic value was analyzed.

Results: The assay demonstrated a linear range from 2.5 to 2,000 pmol/l, with an analytical sensitivity of 2.5 pmol/l. The reproducibility, recovery, and specificity of the immunoassay were demonstrated to be acceptable. Compared with the ECLIA kit from Roche in 124 serum samples (40 patients with ovarian cancer, 35 patients with benign gynecological diseases, and 49 health controls), there is a satisfied correlation coefficient of 0.875. The area under the receiver-operating curve (ROC-AUC) was 0.903 (95% CI was 0.839-0.966, P < 0.001) for HE4, 0.787 (95% CI was 0.694-0.879, P < 0.001) for CA125, and 0.914 (95% CI was 0.866-0.962, P < 0.001) for combined analysis of HE4 and CA125.

Conclusions: A quantitative method (HE4-CLIA) for detecting HE4 in serum was successfully established. Preliminary clinical sample analysis showed HE4-CLIA has a certain clinical value in the screening and diagnosis of ovarian cancer. Moreover, in distinguishing benign from malignant ovarian lesions, HE4 has higher demonstrated accuracy than CA125.