Abstract
BACKGROUND: CLPTM1L (Cleft lip and palate transmembrane protein 1-like) has been previously shown to be overexpressed in lung cancer and is involved in regulating cisplatin sensitivity. In this study, we assessed the relationship between CLPTM1L expression and prognosis of lung cancer in patients and explored its role in regulating cell migration and invasion. METHODS: Immunohistochemistry was used to examine CLPTM1L expression levels on a tissue microarray containing 73 sets of human lung cancer specimens with adjacent normal tissue. The correlation between CLPTM1L expression and patient survival was analysed by the Kaplan-Meier method. In addition, CLPTM1L-knockdown lung cells were used to investigate the effect of CLPTM1L on cell migration and invasion in vitro. RESULTS: The results of immunohistochemical analysis showed that CLPTM1L was overexpressed in lung cancer tissues compared with adjacent normal tissues. Kaplan-Meier analyses revealed that patients with high CLPTM1L expression showed poorer survival than those with low CLPTM1L expression. In addition, in vitro studies revealed that the knockdown of CLPTM1L expression in 95-D lung cancer cells suppressed cell migration and invasion. Further, the loss of CLPTM1L resulted in decreased matrix metalloproteinase-2 (MMP-2) expression in these cells. CONCLUSION: Our data demonstrate that CLPTM1L overexpression can predict poor prognosis in patients with lung cancer and suggest that CLPTM1L might be associated with the regulation of cell migration and invasion.