Background We conducted this study to measure the levels of GRB2 associated binding protein 1 (Gab1) mRNA in cholangiocarcinoma (CCA) tissues and the paired normal tissues. And then assess the prognostic significance of Gab1 in CCA patients.
Methods Quantitative real-time (qRT-PCR) was adopted to confirm the expression levels of Gab1 mRNA in both CCA tissues and normal controls. The Chi-square test was applied to estimate the influence of clinical parameters on Gab1 expression. Kaplan-Meier survival analysis with log-rank test were used to determine overall survival rates of patients with different Gab1 expression. Cox regression analysis was carried out to evaluate prognostic value of factors in CCA patients.
Results According to the qRT-PCR result, increased expression of Gab1 mRNA was found in CCA tissues compared with the paired noncancerous controls (P<0.0001). The Chi-square test demonstrated that the elevated expression of Gab1 was affected by poor differentiation (P=0.022), positive lymph node metastasis (P=0.008) and high TNM stage (P=0.004). However, age, gender, family history and resection margin had no significant influence on Gab1 levels (all, P>0.05). The survival curves suggested that up-regulation of Gab1 was related with poor prognosis of CCA patients. Furthermore, the Cox analysis demonstrated Gab1 was a prognostic biomarker for CCA patients (P=0.000, 95%CI=2.576, HR=1.552-4.275).
Conclusion Taken together, Gab1 expression was increased in CCA and may be a useful biomarker to predict the outcomes of CCA patients.