Axin, an important regulator of beta-catenin, is frequently mutated in human hepatocellular carcinomas (HCCs), and transduction of the wild-type Axin gene (AXIN1) induces apoptosis in HCC cells as well as in colon cancer cells. A novel gene, AXUD1 (AXIN1 up-regulated), has enhanced expression in response to exogenously expressed AXIN1. It is expressed in all human tissues examined, most abundantly in lung, placenta, skeletal muscle, pancreas and leukocytes. Data suggests that AXUD1 may have a tumor-suppressor function in those organs.