Girdin, a regulator of cell motility, is a potential prognostic marker for esophageal squamous cell carcinoma.

Girdin, an actin-binding Akt substrate, regulates actin reconstruction and Akt-dependent cell motility in fibroblasts and in a human breast cancer cell line. We examined whether Girdin is also involved in the motility of esophageal squamous cell carcinoma (ESCC) cells. Immunofluorescent staining and migration assays were performed, using KYSE cell lines, to examine whether Girdin is involved in the motility of ESCC cells. Upon EGF stimulation, Girdin colocalized with filamentous actin (F-actin) in the lamellipodia as determined by immunofluorescent staining. In migration assays, cell motility was significantly reduced in KYSE cell lines transfected with Girdin siRNA compared with the negative control. In addition, we examined the relationship between Girdin expression and clinical data, using specimens resected from ESCC patients. In immunohistochemical (IHC) analyses using specimens resected from ESCC patients, overall survival was significantly longer in cases showing lower Girdin expression compared to cases with higher Girdin expression. Collectively, Girdin appears to be involved in the motility of ESCC cells. The levels of Girdin expression correlated inversely with the survival of ESCC patients. Therefore, in ESCC, Girdin may be a prognostic marker and may serve as a therapeutic target as well.