title: Clinical significance of Rho GDP dissociation inhibitor 2 in colorectal carcinoma.
abstract: BACKGROUND
  Small GTPase proteins, including RhoA, RhoB, RhoC, Rac1, and cdc42, are important molecules for linking cell shape and cell-cycle progression because of their role in both cytoskeletal arrangements and mitogenic signaling. Over-expression of wild-type or constitutively active forms of RhoA has been shown to induce invasive behavior in non-invasive rat hepatoma cells in vitro. In addition, over-expression of RhoC has been found in melanoma cells with increasing metastatic activity as well as inflammatory breast cancer. These results indicate that overexpression of Rho proteins contributes to cancer cell invasion and metastasis. Rho GDP dissociation inhibitor 2 (RhoGDI2) was recently shown to act as a metastasis suppressor gene in bladder cancer. The purpose of this study was to clarify the clinical significance of this gene expression in patients with colorectal carcinoma.
  
  
  METHODS
  Fifty pairs of normal mucosa and cancer specimens obtained at the time of surgery from patients with colorectal cancer (CRC) were subjected to reverse transcription-polymerase chain reaction for RhoGDI2.
  
  
  RESULTS
  No patients with RhoGDI2-higher expression tumors had liver metastasis (0 in 8 cases); however, 33.3% (14 in 42 cases) of patients with RhoGDI2-lower expression tumors had liver metastasis. With regard to outcome in relation to RhoGDI2-positivity, RhoGDI2-higher expression tumors had a significant correlation with superior relapse-free survival (RFS) time as compared to RhoGDI2-lower expression tumors in stage III CRC (log-rank test, P < 0.05). Moreover, multivariate analysis indicated that RhoGDI2 was an independent prognostic factor for RFS.
  
  
  CONCLUSIONS
  RhoGDI2 is a novel predictor of RFS in patients with colorectal carcinoma.
authors.affiliation: Department of Surgery, Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Fujita
authors.forename: Atsuo
authors.initials: A
authors.lastname: Shida
authors.forename: Shuichi
authors.initials: S
authors.lastname: Fujioka
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kurihara
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Okamoto
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Yanaga
mesh_terms: D000328:Adult; D000368:Aged; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology* / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D024601:Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+) / Q000378:metabolism; D020730:Guanine Nucleotide Dissociation Inhibitors / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012008:Recurrence; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors
chemical_list: C569658:ARHGDIB protein, human; D020730:Guanine Nucleotide Dissociation Inhibitors; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D062947:rho-Specific Guanine Nucleotide Dissociation Inhibitors; D024601:Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+)