title: Soluble c-Met Levels Correlated With Tissue c-Met Protein Expression in Patients With Advanced Non-Small-Cell Lung Cancer.
abstract: Immunohistochemistry (IHC) and fluorescent in situ hybridization are reliable methods for identifying c-Met protein expression or c-Met gene amplification. However, each technique requires a high-quality tissue sample, which might not be available. The aim of the present study was to investigate the correlation between the soluble c-Met level and tissue c-Met protein expression and the relationship between these markers and patient prognosis.
  
  
  
  In 198 patients with advanced non-small-cell lung cancer, tumor tissue c-Met expression was determined using IHC according to the H score criteria. Positivity was defined as ≥ 50% of cells with strong staining (IHC 3+). The concentration of c-Met protein in paired plasma samples was measured using a human soluble c-Met quantitative enzyme-linked immunosorbent assay kit, and the predictive value was determined using receiver operating characteristic curve analysis.
  
  
  
  Of the 198 patients, 140 (70.7%) had tissue c-Met-findings and 58 (29.3%) tissue c-Met+findings. Receiver operating characteristic curve analysis showed 67.2% specificity and 65.0% sensitivity for predicting tissue c-Met positivity at a plasma c-Met cutoff of 766 ng/mL. The correlation between the soluble c-Met level and tissue c-Met protein expression was significant (Pearson's r = 0.309; P < .001). Patients with high soluble c-Met levels (> 766 ng/mL) had poorer overall survival than patients with low soluble c-Met levels (9.5 vs. 22.2 months; P < .001). Multivariate analyses demonstrated the same result (hazard ratio, 2.15; 95% confidence interval, 1.334-3.446; P = .002).
  
  
  
  A significant correlation was found between the plasma soluble c-Met levels and tissue c-Met protein expression in patients with advanced non-small-cell lung cancer. A high level of soluble c-Met was associated with a poor prognosis.
authors.affiliation: Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China; Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Hong-Fei
authors.initials: HF
authors.lastname: Gao
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: An-Na
authors.initials: AN
authors.lastname: Li
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Jin-Ji
authors.initials: JJ
authors.lastname: Yang
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Chen
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Xie
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Xu-Chao
authors.initials: XC
authors.lastname: Zhang
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Su
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Na-Na
authors.initials: NN
authors.lastname: Lou
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Hong-Hong
authors.initials: HH
authors.lastname: Yan
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Jie-Fei
authors.initials: JF
authors.lastname: Han
authors.affiliation: Guangdong Lung Cancer Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People's Republic of China. Electronic address: syylwu@live.cn.
authors.forename: Yi-Long
authors.initials: YL
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood / Q000175:diagnosis* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D019859:Proto-Oncogene Proteins c-met / Q000032:analysis* / Q000378:metabolism*; D015996:Survival Rate; D046888:Tissue Array Analysis; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met
keywords: Advanced NSCLC; Immunohistochemistry; Prognosis; Soluble c-Met; c-Met