Molecular profiling of the immune response in colon cancer using protein microarrays: occurrence of autoantibodies to ubiquitin C-terminal hydrolase L3.
We implemented a protein microarray approach to identify proteins that induce a humoral response in colon cancer. Solubilized proteins from the LoVo colon adenocarcinoma cell line were separated into 1760 fractions, arrayed onto nitrocellulose-coated slides, and hybridized with individual sera from 15 newly diagnosed patients with colon cancer, 15 with lung cancer, and 15 healthy subjects. 39/1760 fractions showed enhanced reactivity with sera from patients with colon cancer (p < 0.01) relative to healthy controls. A distinct pattern of reactivity was observed with sera from colon cancer relative to lung cancer. One fraction that exhibited reactivity with 9/15 colon cancer sera was subjected to mass spectrometry leading to the identification of ubiquitin C-terminal hydrolase isozyme 3 (UCH-L3) as a constituent. To validate the occurrence of autoantibodies to UCH-L3, independent analysis was done by means of Western blots. UCH-L3 antibodies were detected in 19/43 sera from patients with colon cancer, and in 0/54 sera from subjects with lung cancer (24), colon adenoma (15) or otherwise healthy (15). Our findings indicate the occurrence of an immune response to a broad set of antigens in colon cancer and the feasibility of identifying the antigenic targets using a combination of protein microarrays and mass spectrometry.
Department of Pediatrics, University of Michigan Medical School, 1150 W. Medical Drive, Ann Arbor, MI 48109-0656, USA.
Myeong J
MJ
Nam
Juan
J
Madoz-Gurpide
Hong
H
Wang
Pascal
P
Lescure
Cecelia E
CE
Schmalbach
Rong
R
Zhao
David E
DE
Misek
Rork
R
Kuick
Dean E
DE
Brenner
Samir M
SM
Hanash
D001323:Autoantibodies / Q000276:immunology*; D003110:Colonic Neoplasms / Q000737:chemistry / Q000276:immunology*; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D008175:Lung Neoplasms / Q000737:chemistry / Q000276:immunology; D013058:Mass Spectrometry; D040081:Protein Array Analysis; D011485:Protein Binding; D013869:Thiolester Hydrolases / Q000276:immunology* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D001323:Autoantibodies; D013869:Thiolester Hydrolases