Serum Proteomic Profiling by Matrix-Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry for Cancer Diagnosis: Next Steps

Publisher Website
Google Scholar
Abstract
Approximately 4 years ago, Petricoin et al. published a new approach for diagnosing ovarian cancer by using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF-MS; ref. 1). The principle of this method is relatively straightforward. It has been hypothesized that proteins or protein fragments released by tumor cells or their environment may enter the general circulation. By using a protein chip, which performs a crude extraction of proteins from whole serum, groups of proteins may be immobilized and then detected by using SELDI (a deri- vative of matrix-assisted laser desorption-ionization, MALDI), in association with a mathematical algorithm. Since that time, the method has been used by numerous investigators to diagnose other malignancies such as breast, prostate, bladder, pancreatic, head and neck, lung, melanoma, liver, nasopharyngeal cancers, gliomas, etc. (2). Invariably, all these articles reported impressive diagnostic sensitivities and specificities, in many cases approaching 100%. None of the currently available serum cancer biomarkers is characterized by such sensitivity/specificity. It is thus natural that this method has created tremendous excitement among scientists, clinicians, the public, and the media (3). Soon after publication of the first report, this author, and others,