Chapter 21, Problem 3NST

Because of its accessibility and biological significance, the proteome of human plasma has been intensively studied and used co provide biomarkers for such conditions as myocardial infarction (troponin) and congestive heart failure (B-type natriuretic peptide). Polanski and Anderson compiled a lise of 1261 proteins, some occurring in plasma, that appear to be differentially expressed in human cancers [Polanski, M., and Anderson, N. L. (2006) Biomarker Insights 2:1–48]. Of these 1261 proteins, only 9 have been recognized by the FDA as tumor-associated proteins. First, what advantage should there be in using plasma as a diagnostic screen for cancer? Second, what criteria should be used to validate that a cancerous state can be assessed through the plasma proteome?