The diagnostic and prognostic role of cytokines in colon cancer

Abstract: In the United States, colorectal cancer (CRC) is the third most common cancer diagnosis in both men and women. Many patients are diagnosed with advanced stage CRC which has a high rate of mortality compared to localized CRC. Developing novel diagnostic tools is important for early detection to decrease both morbidity and mortality. Currently, colonoscopy is the most common screening test, though its effectiveness in reducing mortality remains uncertain and it is costly, invasive and carries risk. Stool-based tests such as fecal occult blood test and fecal immunochemical test for hemoglobin are relatively inexpensive, cause no discomfort and have no risk but lack sufficient specificity or sensitivity. Stool DNA tests may be more sensitive, but are not cost-effective and have not been sufficiently evaluated in population-based studies. To improve diagnostic efficacy, it is necessary to develop tests that limit patient discomfort and are cost-effective while providing adequate sensitivity and specificity. Elucidating serum biomarker profiles for various stages of CRC would provide a platform from which to develop enzyme-linked immunosorbent and multiplex bead array assays for clinical use. Both inflammation-induced and sporadic CRC trigger immune responses that are mediated by cytokine production. Many inflammatory serum proteins have been analyzed for their ability to predict cancer. Patient cohort studies have detected differential expression of inflammatory serum biomarkers in healthy controls compared to persons with various stages of CRC. Moreover, proteomics and animal research have uncovered additional serum factors implicated in CRC. Analysis of known differentially-expressed biomarkers along with further study of potential biomarkers may lead to clinically useful serum biomarker profiles for CRC. Keywords: cytokine, multiplex bead array, inflammatory bowel disease, colitis-associated cancer