NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 7,926 terms related to cancer and medicine.
Browse the dictionary by selecting a letter of the alphabet or by entering a cancer-related word or phrase in the search box.
- listen (PROH-toh-ON-koh-jeen)
- A gene involved in normal cell growth. Mutations (changes) in a proto-oncogene may cause it to become an oncogene, which can cause the growth of cancer cells.