Moving forward in colorectal cancer research, what proteomics has to tell

Abstract

Colorectal cancer is the third most common cancer and is highly fatal. During the last several years, research has been primarily based on the study of expression profiles using microarray technology. But now, investigators are putting into practice proteomic analyses of cancer tissues and cells to identify new diagnostic or therapeutic biomarkers for this cancer. Because the proteome reflects the state of a cell, tissue or organism more accurately, much is expected from proteomics to yield better tumor markers for disease diagnosis and therapy monitoring. This review summarizes the most relevant applications of proteomics the biomarker discovery for colorectal cancer.

Proteomic Techniques in Colorectal Cancer Research

“…This technique is used in disease proteomics to discover diagnostic and prognostic biomarkers for cancer patients. Although 2-D PAGE is laborious and does not resolve highly basic or proteins, smaller than 10 kDa, it is ideal for studying cancer biomarkers (5,21).…”

“…The technique combines protein separation directly with presentation to the mass spectrometer. It is a very attractive technique because of several advantages -easy of use, high throughput, and relatively reasonable cost, allthough still controversial in its reproducibility and ability to detect actual tumor specifi c proteins (5,15,21). It has been developed bioinformatic algorithms for analysis of SELDI-TOF-MS data such as single classifi cation trees, neural nets, genetic algorithms, and random forest algorithms, which share a common goal: to construct a classifi er and discover peak intensities most likely to be responsible for segregating classes of samples.…”

“…The diagnostic models generated from mass spectra acquired using the highresolution q-TOF MS were statistically superior. Different combinations of bioinformatic heuristic parameters (similarity space for cluster classifi cation, learning rate in training of the genetic algorithm) were used to generate different diagnostic models (5,21).…”

“…Genomic and proteomic approaches are applied in studying carcinogenesis, as proteomics allows more reliable analysis. Proteomics, when combined with genomics, may reveal the molecular basis of carcinogenesis and the development of more effective anti-cancer therapies (5). In the ''post-genomic era,'' proteomics identifies tumor markers, pathways controlling growth, differentiation, and death of cells.…”

Comparative proteomics analysis of human gastric cancer

“…However, in most cases, although studies of differential mRNA expression are informative, they do not always correlate with protein concentrations because proteins are often subject to proteolytic cleavage or posttranslational modifications (such as phosphorylation or glycosylation). Cancer biomarkers discovery strategies that target expressed proteins are becoming increasingly popular because proteomic approaches can characterize the proteins, modified or unmodified, involved in cancer progression [2][3][4][5][6] . Recent years, proteomics analysis was has been applied in many kinds of tumors, such as breast cancer [7][8][9] , lung cancer [10,11] , prostate cancer [12] , liver cancer [13][14][15] and ovarian cancer [16] , etc.…”