Serum level of ANGPTL4 as a potential biomarker in renal cell carcinoma

This study aimed to determine the serum levels of angiopoietin-like 4 (ANGPTL4) in patients with renal cell carcinoma (RCC) and explore its potential as a biomarker. Blood samples were taken from 110 patients with RCC, 66 healthy controls, and patients with other solid tumors. Serum ANGPTL4 levels were measured using the enzyme-linked immunosorbent assay, and their correlation with clinical characteristics was further analyzed. Received operating characteristic (ROC) curves, Kaplan-Meier curves, and log-rank analyses were used to evaluate diagnostic and prognostic significance. Serum ANGPTL4 levels were significantly higher in patients with RCC compared with healthy controls and patients with other types of cancers (P<0.0001) and associated with sex, Fuhrman grades, metastasis states, and tumor node metastasis stages (P<0.05), but not with age, tumor size, and histological types (P>0.05). The ROCs/area under the ROC curve analysis indicated an area under the ROC curve of 0.844 (sensitivity = 0.691; specificity = 0.939) and 0.725 (sensitivity = 0.909; specificity = 0.568), respectively, to distinguish patients with RCC from healthy controls and those with metastasis from those without metastasis. The survival analysis revealed that patients with low serum ANGPTL4 had longer progression-free survival compared with those with high serum ANGPTL4 (P = 0.033). The present study suggested that the elevated serum ANGPTL4 level might be a novel diagnostic and prognostic biomarker for patients with RCC.