See Addendum for full list of Affiliations.
SILAC-based quantitative proteomic analysis of gastric cancer secretome
Article first published online: 21 MAY 2013
© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PROTEOMICS - Clinical Applications
Special Issue: Focus on Cancer Proteomics
Volume 7, Issue 5-6, pages 355–366, June 2013
How to Cite
Marimuthu, A., Subbannayya, Y., Sahasrabuddhe, N. A., Balakrishnan, L., Syed, N., Sekhar, N. R., Katte, T. V., Pinto, S. M., Srikanth, S. M., Kumar, P., Pawar, H., Kashyap, M. K., Maharudraiah, J., Ashktorab, H., Smoot, D. T., Ramaswamy, G., Kumar, R. V., Cheng, Y., Meltzer, S. J., Roa, J. C., Chaerkady, R., Prasad, T. S. K., Harsha, H. C., Chatterjee, A. and Pandey, A. (2013), SILAC-based quantitative proteomic analysis of gastric cancer secretome. Prot. Clin. Appl., 7: 355–366. doi: 10.1002/prca.201200069
Colour Online: See the article online to view Figs. 1–5 in colour.
- Issue published online: 18 JUN 2013
- Article first published online: 21 MAY 2013
- Accepted manuscript online: 14 NOV 2012 08:57AM EST
- Manuscript Accepted: 25 OCT 2012
- Manuscript Revised: 24 SEP 2012
- Manuscript Received: 30 JUL 2012
- Council of Scientific and Industrial Research (CSIR)
- NIH. Grant Numbers: U24CA160036, G12 MD007597
- Cell supernatants;
- Early diagnosis;
- Gastric carcinoma;
- In vivo labeling;
- Secreted proteins
Gastric cancer is a commonly occurring cancer in Asia and one of the leading causes of cancer deaths. However, there is no reliable blood-based screening test for this cancer. Identifying proteins secreted from tumor cells could lead to the discovery of clinically useful biomarkers for early detection of gastric cancer.
A SILAC-based quantitative proteomic approach was employed to identify secreted proteins that were differentially expressed between neoplastic and non-neoplastic gastric epithelial cells. Proteins from the secretome were subjected to SDS-PAGE and SCX-based fractionation, followed by mass spectrometric analysis on an LTQ-Orbitrap Velos mass spectrometer. Immunohistochemical labeling was employed to validate a subset of candidates using tissue microarrays.
We identified 2205 proteins in the gastric cancer secretome of which 263 proteins were overexpressed greater than fourfold in gastric cancer-derived cell lines as compared to non-neoplastic gastric epithelial cells. Three candidate proteins, proprotein convertase subtilisin/kexin type 9 (PCSK9), lectin mannose binding 2 (LMAN2), and PDGFA-associated protein 1 (PDAP1) were validated by immunohistochemical labeling.
Conclusions and clinical relevance
We report here the largest cancer secretome described to date. The novel biomarkers identified in the current study are excellent candidates for further testing as early detection biomarkers for gastric adenocarcinoma.