Gerardo-Ramirez et al. [14] demonstrated the tumor suppressive properties of exogenous GDF11 in hepatocellular carcinoma cells, and Zhang et al. [15] demonstrated that GDF11 exerts its effects through Smad2/3 signaling, and that it plays a tumor suppressor role in liver cancer. The gene discussed is GDF11; the disease is hepatocellular carcinoma.