Overexpression of T lymphoma invasion and metastasis 1 predict renal cell carcinoma metastasis and overall patient survival.

T lymphoma invasion and metastasis 1 (Tiam1) is a metastasis-related gene of T lymphoma that is also involved in the metastasis of a variety of other cancers, but little research has been done yet to test its usefulness as a prognostic marker in renal cell carcinoma (RCC). In the present study, we investigated Tiam1 expression and its prognostic significance in RCC. RCC surgical tissue samples were taken from 136 patients with RCC who had been followed up for 5 years. The Tiam1 expressions in the 136 clinical samples were tested by immunohistochemical assay to find their association with prognostic significance. We found that 93 of 136 (68.4%) paraffin-embedded archival RCC biopsies showed positive expression of Tiam1. Statistical analysis showed that there was significant difference of Tiam1 overexpression in patients categorized according to lymph node metastasis. Patients with higher Tiam1 expression had shorter overall survival time, whereas patients with lower Tiam1 expression had better survival. Multivariate analysis showed that Tiam1 overexpression was an independent prognostic indicator for patient's survival. Our results suggest that Tiam1 protein is a valuable marker of RCC progression. High Tiam1 expression is associated with poor overall survival in patients with RCC.