title: Identification of a new protein biomarker for colorectal cancer diagnosis.
abstract: As one of the most common cancers, colorectal cancer (CRC) is a major public health issue worldwide. Thus, the identification of novel biomarkers to aid in the early diagnosis of CRC is crucial. The aim of the present study was to identify a novel protein biomarker for CRC, and to identify its structure. In this study, a total of 99 serum samples from 73 CRC patients and 26 healthy controls were collected and analyzed by SELDI-TOF-MS. The biomarkers were separated using HPLC and detected with MALDI-TOF-MS. The qualified peaks were ranked by p-value of non-parametric tests and the top 10 peaks displaying significant differences were selected. Among the 10 protein biomarkers, the concentration of a 3.9‑kDa protein in the serum of the CRC patients was much lower than that in the healthy controls. Therefore, the 3.9‑kDa protein was selected as a biomarker for CRC and its separation and purification were performed. The structure of the 3.9-kDa protein biomarker was determined by LC-MS/MS, and was confirmed to be a fragment of serine/theonine kinase 4 (MST1/STK4). The 3.9‑kDa protein biomarker had high sensitivity and specificity for CRC, and its potential clinical application warrants further investigation.
authors.affiliation: Cancer Institute, Key Laboratory of Cancer Prevention and Intervention, China National Ministry of Education, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, PR China.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Zhai
authors.forename: Jie-Kai
authors.initials: JK
authors.lastname: Yu
authors.forename: Fu-Quan
authors.initials: FQ
authors.lastname: Yang
authors.forename: Shu
authors.initials: S
authors.lastname: Zheng
mesh_terms: D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D014408:Biomarkers, Tumor / Q000097:blood*; D016022:Case-Control Studies; D002853:Chromatography, Liquid; D015179:Colorectal Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D019295:Computational Biology; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009367:Neoplasm Staging; D010446:Peptide Fragments / Q000097:blood*; D017346:Protein Serine-Threonine Kinases / Q000097:blood* / Q000235:genetics; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D000099317:Hippo Kinases
chemical_list: D014408:Biomarkers, Tumor; D047908:Intracellular Signaling Peptides and Proteins; D010446:Peptide Fragments; D017346:Protein Serine-Threonine Kinases; C095566:STK4 protein, human; D000099317:Hippo Kinases