title: Isocitrate dehydrogenase 1 is a novel plasma biomarker for the diagnosis of non-small cell lung cancer.
abstract: OBJECTIVE
  Effective biomarkers for the diagnosis of non-small cell lung cancer (NSCLC) are needed. We previously showed that isocitrate dehydrogenase 1 (IDH1) is significantly increased in NSCLC tumors. This study aimed to examine the plasma levels of IDH1 in a large patient population to evaluate its effectiveness in NSCLC diagnosis.
  
  
  METHODS
  The plasma levels of IDH1, CA125, Cyfra21-1, and CEA were assayed by ELISA. Blood samples were obtained from 1,422 participants (943 patients with NSCLC and 479 healthy controls). The samples were randomly divided into a training set and a test set. Receiver operating characteristic and binary logistic regression analyses were applied to evaluate diagnostic efficacy and establish diagnostic mathematical models.
  
  
  RESULTS
  Plasma IDH1 levels were significantly higher in patients with NSCLCs than in healthy controls (P < 0.001). The diagnostic use of IDH1 in lung adenocarcinoma [area under curve (AUC): 0.858 and 0.810; sensitivity: 77.1% and 76.2%; specificity: 82.9% and 76.6%; in the training set and test set, respectively] was significantly greater than that of CA125, Cyfra21-1, or CEA (P < 0.001). The model combining IDH1 with CEA, CA125, and Cyfra21-1 was more effective for lung adenocarcinoma diagnosis than IDH1 alone (sensitivity and specificity in the training set: 75.8%, 89.6%; test set: 86.3%, 70.7%). In addition, the plasma levels of IDH1 could contribute to the diagnostic model of lung squamous cell carcinoma.
  
  
  CONCLUSIONS
  IDH1 can be used as a plasma biomarker for the diagnosis of NSCLCs, particularly lung adenocarcinoma, with relatively high sensitivity and specificity.
authors.affiliation: Authors' Affiliation: Department of Thoracic Surgery, Cancer Institute and Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Sun
authors.forename: Zhaoli
authors.initials: Z
authors.lastname: Chen
authors.forename: Fengwei
authors.initials: F
authors.lastname: Tan
authors.forename: Baihua
authors.initials: B
authors.lastname: Zhang
authors.forename: Ran
authors.initials: R
authors.lastname: Yao
authors.forename: Chengcheng
authors.initials: C
authors.lastname: Zhou
authors.forename: Jiagen
authors.initials: J
authors.lastname: Li
authors.forename: Yibo
authors.initials: Y
authors.lastname: Gao
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Liu
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Tan
authors.forename: Fang
authors.initials: F
authors.lastname: Zhou
authors.forename: Max Y F
authors.initials: MY
authors.lastname: He
authors.forename: Kang
authors.initials: K
authors.lastname: Shao
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Bin
authors.initials: B
authors.lastname: Qiu
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.forename: Yue
authors.initials: Y
authors.lastname: Yu
authors.forename: Suya
authors.initials: S
authors.lastname: Wang
authors.forename: Yuda
authors.initials: Y
authors.lastname: Zhao
authors.forename: Xuejiao
authors.initials: X
authors.lastname: Shi
authors.forename: Jie
authors.initials: J
authors.lastname: He
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000175:diagnosis*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000097:blood; D019540:Area Under Curve; D014408:Biomarkers, Tumor / Q000097:blood*; D018394:CA-125 Antigen / Q000097:blood; D002272:Carcinoembryonic Antigen / Q000097:blood; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood / Q000175:diagnosis*; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000175:diagnosis*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000097:blood*; D053539:Keratin-19 / Q000097:blood; D008175:Lung Neoplasms / Q000097:blood / Q000175:diagnosis*; D008297:Male; D008565:Membrane Proteins / Q000097:blood; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012372:ROC Curve
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D002272:Carcinoembryonic Antigen; D053539:Keratin-19; C451759:MUC16 protein, human; D008565:Membrane Proteins; C102012:antigen CYFRA21.1; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human