Noninvasive molecular biomarkers for the detection of colorectal cancer

Colorectal cancer (CRC) is the third most common malignancy in the world. Because CRC develops slowly from removable precancerous lesions, detection of the disease at an early stage during regular health examinations can reduce both the in-cidence and mortality of the disease. Although sigmoidoscopy offers significant improvements in the detection rate of CRC, its diagnostic value is limited by its high costs and inconvenience. Therefore, there is a compelling need for the identification of noninvasive biomarkers that can enable earlier detection of CRC. Accordingly, many validation studies have been con-ducted to evaluate genetic, epigenetic or protein markers that can be detected in the stool or in serum. Currently, the fe-cal-occult blood test is the most widely used method of screen-ing for CRC. However, advances in genomics and proteomics combined with developments in other relevant fields will lead to the discovery of novel non invasive biomarkers whose use-fulness will be tested in larger validation studies. Here, non-invasive molecular biomarkers that are currently used in clin-ical settings and have the potential for use as CRC biomarkers are discussed. [BMB reports 2008; 41(10): 685-692]