Small GTPase proteins, including RhoA, RhoB, RhoC, Rac1 and cdc42, are molecules that have significant roles in linking cell shape and cell cycle progression in cytoskeletal arrangements and mitogenic signaling.
Rho GDP dissociation inhibitor 2 (
RhoGDI2) has recently been identified as a metastasis suppressor gene in models of
bladder cancer.
RhoGDI2 has also been identified as a potential regulator of
tumorigenesis and
cancer progression. The present study aimed to clarify the significance of
RhoGDI2 gene expression in gastric
carcinoma and to evaluate the outcome of affected patients. A total of 46 pairs of normal mucosa and
cancer specimens were obtained from patients who had undergone a
gastrectomy for primary gastric
carcinoma and were subjected to semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) for
RhoGDI2. The expression of
RhoGDI2 mRNA was significantly higher in early-stage
gastric cancer specimens compared with the normal gastric epithelium samples. By contrast, the depth of the
tumor was negatively correlated with
RhoGDI2 mRNA expression. In addition, a reduced expression of
RhoGDI2 mRNA was associated with venous system invasion and
lymph node metastasis.
RhoGDI2 mRNA was more frequently expressed in differentiated
adenocarcinoma compared with poorly-differentiated
adenocarcinoma. Although the statistical significance was not established, RhoGDI2-positive patients tended to have a superior oncological outcome compared with RhoGDI2-negative patients. The reduced expression of
RhoGDI2 mRNA in gastric
carcinoma is associated with venous system invasion and
lymph node metastasis.