Identification of serum biomarkers for colon cancer by proteomic analysis

Abstract

Colorectal cancer (CRC) is often diagnosed at a late stage with concomitant poor prognosis. Early detection greatly improves prognosis; however, the invasive, unpleasant and inconvenient nature of current diagnostic procedures limits their applicability. No serum-based test is currently of sufficient sensitivity or specificity for widespread use. In the best currently available blood test, carcinoembryonic antigen exhibits low sensitivity and specificity particularly in the setting of early disease. Hence, there is great need for new biomarkers for early detection of CRC. We have used surface-enhanced laser desorbtion/ionisation (SELDI) to investigate the serum proteome of 62 CRC patients and 31 noncancer subjects. We have identified proteins (complement C3a des-arg, a1-antitrypsin and transferrin) with diagnostic potential. Artificial neural networks trained using only the intensities of the SELDI peaks corresponding to identified proteins were able to classify the patients used in this study with 95% sensitivity and 91% specificity.

Identification of disease- and therapy-associated proteome changes in the sera of patients with myelodysplastic syndromes and del(5q)

“…All these proteins have been identified by others as disease-associated markers. [29][30][31][32][33][34][35][36] We obtained a classification model that could distinguish between the diseased and the control subjects with high sensitivity and specificity. Because of the restriction of sample size, we assessed the performance of this model using a procedure of 10-fold cross validation.…”

Adenovirus 5 E1A is responsible for increased expression of insulin receptor substrate 4 in established adenovirus 5-transformed cell lines and interacts with IRS components activating the PI3 kinase/Akt signalling pathway

“…Protein bands were excised and tryptic peptides were produced (Ward et al, 2006). Peptides were analysed using an LCQ DECA XP Plus ion trap (Thermo Fisher Scientific, Waltham, MA, USA).…”

Identification of macrophage migration inhibitory factor and human neutrophil peptides 1–3 as potential biomarkers for gastric cancer

“…SELDI combines on-chip retentate chromatography with mass spectrometry to generate 'proteomic profiles' and can be applied to fluids, such as serum, plasma and urine and tissue extracts (e.g., Rogers et al, 2003;Albrethsen et al, 2005;Ward et al, 2006Ward et al, , 2008Brozkova et al, 2008). SELDI provides a wealth of information on the low molecular proteome (o20 kDa), which contains diagnostic information (Villanueva et al, 2006).…”