title: LyGDI is a promising biomarker for ovarian cancer.
abstract: BACKGROUND
  LyGDI is an inhibitor of Rho protein activation by blocking its transformation between guanosine 5'-diphosphate- and guanosine 5'-triphosphate-bound states. The aim of this study was to investigate the usefulness of LyGDI as a biomarker for the detection of ovarian cancer, and its specificity and sensitivity were compared with those of cancer antigen 125 (CA125).
  
  
  METHODS
  The serum levels of LyGDI were determined by enzyme-linked immunosorbent assay in 42 patients with ovarian disease, including 30 ovarian cancers and 12 benign ovarian lesions, and 76 healthy controls. The expression of LyGDI was also evaluated by immunohistochemical staining in resected ovarian tissues of these patients.
  
  
  RESULTS
  The serum LyGDI level of cancers was significantly greater than those of the benign and healthy groups (P = 0.002 and P < 0.0001, respectively), whereas no difference was observed between the benign and control groups (P = 0.889). Based upon receiver operating characteristic curve analysis, LyGDI levels were able to distinguish ovarian cancer from benign ovarian disease (P = 0.0001) and healthy control (P < 0.0001; areas under the receiver operating characteristic curves, 0.876 and 0.833, respectively). For ovarian cancers, 83.3% (25/30) or 80.0% (24/30) was identified by serum LyGDI (> or = 1.5 ng/mL) alone or by CA125 (>35 U/mL) alone. It is of particular importance to note that all cancer patients were identified by use of both markers, and the specificity was 83.3% for the benign group. Moreover, in early-stage cancers, 88.9% (8/9) had elevated serum LyGDI levels as compared with 44.4% (4/9) elevation of CA125 levels (P = 0.125). Immunohistochemical staining confirmed the expression of LyGDI on cancerous epithelial cells other than benign ovarian epithelium.
  
  
  CONCLUSIONS
  These results suggest that LyGDI has significant potential as a marker for detection of ovarian cancer in the patients with ovarian enlargement, including detection of early-stage cancers.
authors.affiliation: Department of Cell Biology, Peking University Health Science Center, Beijing, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhen
authors.forename: Shaomin
authors.initials: S
authors.lastname: Yang
authors.forename: Hounan
authors.initials: H
authors.lastname: Wu
authors.forename: Shuling
authors.initials: S
authors.lastname: Wang
authors.forename: Jingqiao
authors.initials: J
authors.lastname: Lv
authors.forename: Lijun
authors.initials: L
authors.lastname: Ma
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhang
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000097:blood / Q000175:diagnosis; D002288:Adenocarcinoma, Mucinous / Q000097:blood / Q000175:diagnosis; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D018394:CA-125 Antigen / Q000097:blood; D016022:Case-Control Studies; D018284:Cystadenocarcinoma, Serous / Q000097:blood / Q000175:diagnosis; D016889:Endometrial Neoplasms / Q000097:blood / Q000175:diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000097:blood*; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000097:blood / Q000175:diagnosis*; D010053:Ovary / Q000378:metabolism; D011379:Prognosis; D012680:Sensitivity and Specificity; D025521:Tumor Suppressor Proteins / Q000097:blood*; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors
chemical_list: C569658:ARHGDIB protein, human; D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D020730:Guanine Nucleotide Dissociation Inhibitors; D025521:Tumor Suppressor Proteins; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors