Determining ProGRP and isoforms in lung and thyroid cancer patient samples: comparing an MS method with a routine clinical immunoassay.

Abstract

This paper compares two methods to determine the tumor marker progastrin-releasing peptide (ProGRP): as routine assay, the automated time-resolved immunofluorometric assay (TR-IFMA), which allows total ProGRP determination; and the immunocapture liquid chromatography selected reaction monitoring mass spectrometry (LC-SRM-MS) method, which additionally allows isoform differentiation. The investigation included 60 serum samples from patients suffering from various cancer diseases which may cause elevated ProGRP levels (small cell lung carcinoma; SCLC, non-small cell lung carcinoma; NCLC; and medullary thyroid cancer; MTC, as well as some with unspecific diagnosis). The two methods showed good correlation (R (2) = 0.887). However, the MS method determines the total ProGRP concentration systematically approximately 30 % lower than the TR-IFMA, implying that the absolute values generated by the methods are not interchangeable. The MS method gives additional information about isoform levels in the samples, providing novel insight into isoform expression on the protein level.

• Authors: Silje Bøen Torsetnes, Marianne Nordlund Broughton, Elisabeth Paus, Trine Grønhaug Halvorsen, Léon Reubsaet
• Journal: Analytical and bioanalytical chemistry (Anal Bioanal Chem) Vol. 406 Issue 11 Pg. 2733-8 (Apr 2014) ISSN: 1618-2650 [Electronic] Germany
• PMID: 24518900 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Biomarkers, Tumor
• Peptide Fragments
• Recombinant Proteins
• pro-gastrin-releasing peptide (31-98)

Topics

• Biomarkers, Tumor (blood)
• Humans
• Immunoassay (methods)
• Lung Neoplasms (blood, diagnosis)
• Mass Spectrometry (methods)
• Peptide Fragments (blood)
• Recombinant Proteins (blood)
• Thyroid Neoplasms (blood, diagnosis)