Discovery and Verification of Potential Cancer Biomarkers: An Integration of QqTOF, Multiple-Reaction Monitoring and Immunohistochemistry.

摘要

Mass spectrometry-based proteomic strategies involving mass tagging of peptides permit the identification and quantification of proteins from control and test samples of tissue homogenates simultaneously. These approaches, when applied to cancer and non-malignant controls, provide a means for detection of differentially expressed proteins. When used to screen larger cohorts of samples, such techniques can indicate proteins that are consistently differentially expressed in the cancer samples, thus suggesting their possible utility as cancer biomarkers. Our efforts to discover potential biomarkers for endometrial cancer (EmCa) using iTRAQ technology and LC-MS/MS analysis on a QqTOF-type instrument have yielded promising results. Some of these potential biomarkers have been validated in studies involving immunohistochemistry in a tissue-microarray (TMA) format. In an effort to maximize the numbers of samples in which the potential cancer markers (PCMs) can be detected and quantified, as well as to improve sensitivity, we have developed a targeted approach that involves the use of multiple-reaction monitoring (MRM) scans on a triple-quadrupole/linear ion-trap mass spectrometer.