Measuring serum human epididymis secretory protein autoantibody as an early biomarker of lung cancer

BACKGROUND: Lung cancer (LC) is one of the most common types of malignant tumors and is the most prominent cause of tumor-related death worldwide. LC is a heterogeneous disease caused by somatic cell mutations and dysregulation in several signaling pathways. Understanding these pathways provides the basis for detecting LC. LC screening and diagnosis in current clinic still rely on computed tomography (CT), but its high false positive rates and cost may prevent it from being a routine screening method. Therefore, the discovery of new non-invasive and more valuable biomarkers may present an improved diagnostic approach for LC, and potentially provide more useful information for the prognosis and treatment of LC in patients. This study investigated the potential of detecting serum autoantibodies produced against human epididymis secretory protein 4 (HE4) for LC diagnosis in high-risk groups. METHODS: Serum samples from 61 patients with LC were included in this study, and another 53 serum samples from healthy donors or benign lung diseases (BLD) patients were collected as the control group. The samples were analyzed with enzyme-linked immunosorbent assays (ELISA). RESULTS: ELISA results showed significantly higher levels of serum autoantibodies against HE4 in samples from LC patients compared to the control group (P<0.001). Analysis of HE4 autoantibodies showed a receiver operating characteristic (ROC) curve indicating 67.21% sensitivity, 96.23% specificity, and an area under the curve (AUC) of 0.848. Levels of HE4 autoantibodies can discriminate early-stage LC patients from the control group with a 54.76% sensitivity. CONCLUSIONS: Detecting serum HE4 autoantibody levels may be a potential biomarker in high-risk groups of LC. We present a new method for the diagnosis of LC in the clinic.