title: Identification of haptoglobin peptide as a novel serum biomarker for lung squamous cell carcinoma by serum proteome and peptidome profiling.
abstract: To date, a number of potential biomarkers for lung squamous cell cancer (SCC) have been identified; however, sensitive biomarkers are currently lacking to detect early stage SCC due to low sensitivity and specificity. In the present study, we compared the 7 serum proteomic profiles of 11 SCC patients, 7 chronic obstructive pulmonary disease (COPD) patients and 7 healthy smokers as controls to identify potential serum biomarkers associated with SCC and COPD. Two-dimensional difference gel electrophoresis (2D-DIGE) and mass-spectrometric analysis (MS) using an affinity column revealed two candidate proteins, haptoglobin (HP) and apolipoprotein 4, as biomarkers of SCC, and α-1-antichymotrypsin as a marker of COPD. The iTRAQ technique was also used to identify SCC-specific peptides. HP protein expression was significantly higher in SCC patients than in COPD patients. Furthermore, two HP protein peptides showed significantly higher serum levels in SCC patients than in COPD patients. We established novel polyclonal antibodies for the two HP peptides and subsequently a sandwich enzyme-linked immunosorbent assay (ELISA) for the quantification of these specific peptides in patient and control sera. The sensitivity of detection by ELISA of one HP peptide (HP216) was 70% of SCC patients, 40% of COPDs patients and 13% of healthy controls. We also measured CYFRA, a cytokeratin fragment clinically used as an SCC tumor marker, in all the 28 cases and found CYFRA was detected in only seven SCC cases. However, when the measurement of HP216 was combined with that of CYFRA, 100% (10 of 10 patients) of SCC cases were detected. Our proteomic profiling demonstrates that the SCC-specific HP peptide HP216 may potentially be used as a diagnostic biomarker for SCC.
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Okano
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Seike
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Kuribayashi
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Soeno
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, The Respiratory Care Clinic, Nippon Medical School, Tokyo 113-8603, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Ishii
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, The Respiratory Care Clinic, Nippon Medical School, Tokyo 113-8603, Japan.
authors.forename: Kozui
authors.initials: K
authors.lastname: Kida
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, Bunkyo-ku, Tokyo 113-8603, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Gemma
mesh_terms: D000328:Adult; D000368:Aged; D001054:Apolipoproteins A / Q000097:blood; D014408:Biomarkers, Tumor / Q000097:blood*; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000175:diagnosis; D016022:Case-Control Studies; D015180:Electrophoresis, Gel, Two-Dimensional; D004797:Enzyme-Linked Immunosorbent Assay; D006242:Haptoglobins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007633:Keratins / Q000378:metabolism; D008175:Lung Neoplasms / Q000097:blood* / Q000175:diagnosis; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D010446:Peptide Fragments / Q000737:chemistry*; D020543:Proteome / Q000378:metabolism*; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood; D012907:Smoking; D000514:alpha 1-Antichymotrypsin / Q000097:blood
chemical_list: D001054:Apolipoproteins A; D014408:Biomarkers, Tumor; D006242:Haptoglobins; D010446:Peptide Fragments; D020543:Proteome; D000514:alpha 1-Antichymotrypsin; C022205:apolipoprotein A-IV; C000612076:haptoglobin (216-228), human; D007633:Keratins