Immunohistochemical analysis showed that 60 of 98 (61.22%) adenocarcinoma tissues showed high expression of Tiam1, and high Tiam1 expression was significantly associated with advanced TNM stage (P < 0.0005) and lymph node status (P < 0.0005) of lung adenocarcinoma. Here, TIAM1 is linked to lung adenocarcinoma.