NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,176 terms related to cancer and medicine.
We offer a widget that you can add to your website to let users look up cancer-related terms. Get NCI’s Dictionary of Cancer Terms Widget.
- listen (AN-tee-proh-JES-tin)
- A substance that prevents cells from making or using progesterone (a hormone that plays a role in the menstrual cycle and pregnancy). Antiprogestins may stop some cancer cells from growing and they are being studied in the treatment of breast cancer. An antiprogestin is a type of hormone antagonist.