Abstract: The human HLJ1 tumor suppressor gene is herein defined as regulated by promoter, enhancer, and silencer regions. HLJ1 promoter activity and gene expression are inversely correlated with metastatic ability. HLJ1 is highly expressed, and inducible, in cells with low metastatic ability and expressed to a lesser extent in highly metastatic cells. HLJ1 gene expression suppressed the growth of human lung adenocarcinoma cells in vitro, and inhibited tumor growth in vivo. It also impeded the motility of human adenocarcinoma cells and reduced the anchorage-independent growth capacity and invasiveness of metastatic lung adenocarcinoma cells. The degree to which human lung adenocarcinoma patients express HLJ1 predicts their survival prognosis and their probability of relapse.