Serum protein kinase Cα as a diagnostic biomarker of cancers

Cancer Biomark. 2013;13(2):99-103. doi: 10.3233/CBM-130340.

Abstract

Background: Several serum biomarkers such as antigens, soluble proteins, metabolites, and genes have been identified for the diagnosis of cancers and for monitoring the recurrence after cancer treatment.

Methods: In the present study, a protein kinase C (PKC) α-specific peptide substrate was phosphorylated with serum samples collected from cancer-bearing mice (U87, A431, HepG2, and A549) and the phosphorylation ratio was detected by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS).

Results: The phosphorylation ratio for peptide substrates significantly increased in the serum of cancer-bearing mice compared with the ratio found in control mice. The addition of a PKCα inhibitor induced a concentration-dependent decrease in phosphorylation ratios, but the non-PKCα inhibitors, rottlerin and H-89, did not significantly effect phosphorylation ratios.

Conclusions: These results suggest that serum activated PKCα is a good biomarker applicable to cancer diagnosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomarkers, Tumor / blood*
  • Cell Line, Tumor
  • Humans
  • Male
  • Mice
  • Neoplasms / blood*
  • Neoplasms / diagnosis*
  • Peptides / metabolism
  • Phosphorylation
  • Protein Kinase C-alpha / blood*
  • Protein Kinase C-alpha / metabolism
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Substrate Specificity

Substances

  • Biomarkers, Tumor
  • Peptides
  • Protein Kinase C-alpha