[Suppression of proteolysis in serum samples after collection is NOT a good thing?]
>>J. Clin. Invest. 116:26-30 (2006). doi:10.1172/JCI27467.
Commentary
Serum peptidome for cancer detection: spinning biologic trash into diagnostic gold
Lance A. Liotta and Emanuel F. Petricoin Center for Applied Proteomics and Molecular Medicine, College of Arts and Sciences, George Mason University, Manassas, Virginia, USA.
Address correspondence to: Lance A. Liotta or Emanuel F. Petricoin, Center for Applied Proteomics and Molecular Medicine, College of Arts and Sciences, George Mason University, 10900 University Boulevard, MS 4E3, Room 181A, Manassas, Virginia 20110, USA. Phone: (703) 993-9444; Fax: (703) 993-4288; E-mail: lliotta@gmu.edu (L.A. Liotta). Phone: (703) 993-8646; Fax: (703) 993-4288; E-mail: epetrico@gmu.edu (E.F. Petricoin).
The low molecular weight region of the serum peptidome contains protein fragments derived from 2 sources: (a) high-abundance endogenous circulating proteins and (b) cell and tissue proteins. While some researchers have dismissed the serum peptidome as biological trash, recent work using mass spectrometry–based (MS-based) profiling has indicated that the peptidome may reflect biological events and contain diagnostic biomarkers. In this issue of the JCI, Villanueva et al. report on MS-based peptide profiling of serum samples from patients with advanced prostate, bladder, or breast cancer as well as from healthy controls. Surprisingly, the peptides identified as cancer-type–specific markers proved to be products of enzymatic breakdown generated after patient blood collection. The impact of these results on cancer biomarker discovery efforts is significant because it is widely believed that proteolysis occurring ex vivo should be suppressed because it destroys endogenous biomarkers. Villanueva et al. now suggest that this suppression may in fact be preventing biomarker generation.<<
Here's the link to the article which is free:
jci.org
VERY INTERESTING. One could conceivably get results by both methods, perhaps by drawing a slightly larger sample, and doing an analysis before and after proteolysis suppression. Presumably this would give better predictive value, though it would cost more. A whole new area to mine . . .
Cheers, Tuck |