Role of HOXB7 in regulation of progression and metastasis of human lung adenocarcinoma.

Dysregulation of homeobox B7 (HOXB7), a member of the homeobox genes family, was suggested to play a role in regulation of tumorigenesis and metastases of some cancers. However, the functions of HOXB7 in association with lung adenocarcinoma (LAC) have not been investigated. The correlation between the level of HOXB7 expression and cancer progression in patients is not known. In this study, through analysis of 75 LAC samples and their corresponding normal lung epithelium tissues immunohistochemistry (IHC), we demonstrate that HOXB7 was overexpressed in LAC specimens compared to their paired normal lung epithelium tissues. Increased expression of HOXB7 was associated with poor clinical outcomes, correlating significantly with a short survival time in patients who had LAC. Moreover, HOXB7 expression level was correlated with the tumor status (P = 0.028), nodal status (P = 0.012) and tumor stage (P = 0.029) in lung adenocarcinoma. Silencing HOXB7 inhibited cell growth and metastases in vitro and in vivo. In conclusion, our results suggest that HOXB7 promotes LAC progression by enhancing proliferation and metastasis. The increased expression of HOXB7 in LAC is a potential prognostic indicator for patients, and HOXB7 could be a novel target for treatment of LAC patients.