Elevated serum antibodies against insulin-like growth factor-binding protein-2 allow detecting early-stage cancers: evidences from glioma and colorectal carcinoma studies.
 

Li Y, Jiang T, Zhang J, Zhang B, Yang W, You G, Xu K, Wu J, Luo C, Song SW.
Source
Department of Oncology, Beijing Shijitan Hospital, The Capital Medical University, Beijing.

Abstract

BACKGROUND:
Tumor-specific immunity of insulin-like growth factor-binding protein-2 (IGFBP-2) has been reported in several cancers. We aimed to assess the role of serum IGFBP-2 antibodies (IGFBP-2 Abs) in early cancer detection.

PATIENTS AND METHODS:
Glioma and colorectal carcinoma (CRC) were used as models. Serum IGFBP-2 and IGFBP-2 Abs were measured in 260 tumor patients (145 gliomas, 45 colorectal polyps, and 70 CRCs) and 141 controls. Receiver operating characteristic curves were applied.

RESULTS:
Serum IGFBP-2 Ab levels were significantly elevated in tumors (mean: 82 ng/ml, median: 17 ng/ml, range: 0-1387 ng/ml) compared with controls (11, 0, 0-212 ng/ml) (P < 0.0001) and higher in early than advanced cancers opposite of serum IGFBP-2 levels. IGFBP-2 Abs effectively discriminated between controls and grade II and III gliomas [area under the curve (AUC): 0.821-0.864; 95% confidence interval (CI) = 0.762-0.936; P < 0.0001], and CRC I-II (AUC: 0.668; 95% CI = 0.566-0.770; P = 0.002) as well as indicative of advanced polyps at high risk of CRC (AUC: 0.72; 95% CI = 0.630-0.811; P < 0.0001). The sensitivity and specificity for diagnosing grade II-III gliomas reached 66%-84% and 81%. Combined serum IGFBP-2 and IGFBP-2 Abs augmented the discriminative power of all stage tumors (AUC: 0.823), gliomas (AUC: 0.800), and CRCs (AUC = 0.917).

CONCLUSION:
Our results first demonstrate IGFBP-2 Abs for early cancer detection and in combination of serum