Identification of Preferentially Expressed Antigen of Melanoma as a Potential Tumor Suppressor in Lung Adenocarcinoma

BACKGROUND Preferentially expressed antigen of melanoma (PRAME) is known as a tumor-associated antigen that is altered in a variety of malignancies, including lung cancer. However, the role of PRAME in lung cancer remains unclear. MATERIAL AND METHODS We analyzed the expression of PRAME in human lung adenocarcinomas and studied the function of PRAME using small interfering RNA (siRNA)-induced gene knockdown in lung cancer cell lines PC9 and A549. RESULTS We found that PRAME expression is down-regulated in lung adenocarcinomas. Knockdown of PRAME promoted proliferation and suppressed apoptosis of PC9 and A549 cells. CONCLUSIONS In line with its roles in controlling cell growth, RPAME regulates multiple critical cell-growth related genes, including IGF1R oncogene. IGF1R up-regulation contributes to increase of cell growth upon the knockdown of PRAME. Taken together, our results suggest that PRAME has inhibitory roles in lung cancer.