While its function in transformed human tumor cells is not known, two studies in untransformed human and mouse kidney podocytes have put forth that DDN encodes a proline-rich protein that may play a role in TGF-β1-induced apoptosis [29], possibly through its function as a transcription factor that promotes the cytosolic expression of cathepsin L [30]. The gene discussed is TGFB1; the disease is neoplasm.