Blood-derived molecular signatures as biomarker panels for the early detection of colorectal cancer

Colorectal cancer (CRC) is one of the leading causes of tumor morbidity and mortality worldwide. Endoscopy is currently the main screening method, but the invasiveness and high cost hamper the application of endoscopy in asymptomatic patients with a risk of CRC and lead to a low diagnostic rate for early CRC. In recent years, the progress of transcriptomics, epigenetics, immunomics and metabolomics has greatly contributed to the identification of novel molecular markers for the noninvasive screening of CRC, and many molecules in various biological processes have been identified and evaluated for CRC detection. However, individual molecules always have insufficient diagnostic performance as biomarkers for the detection of CRC; therefore, a frequent strategy to overcome this deficiency is the use of molecule signatures as biomarker panels to improve the diagnostic power. Here, we reviewed the diagnostic performance of blood-derived molecular signatures (mRNAs, microRNAs, autoantibodies, and metabolites) as biomarker panels for CRC detection, particularly for early detection, and discussed their limitations and prospects.