Concerns regarding the veracity of the images and data presented in the article, “MicroRNA-21 regulates expression of the PTEN tumor suppressor gene in human hepatocellular cancer” by Meng F, et al. Gastroenterology 2007;133(2):647–658, were brought to the attention of the editors. The journal contacted the authors, who were able to validate their original results using an independent set of samples.