Scientists don’t know for sure. Since chemotherapy and radiation kill cells that divide often, stem cells may be less vulnerable because they rarely divide. Some scientists believe cancer stem cells may have genetic mutations that make them resistant to damage from chemotherapy or radiation, or cancer stem cells may be able to repair DNA damage more rapidly than normal cells.
Teas are a great way to get the benefits of sage all you need to do is steep one teaspoon of sage in a cup of water for about 10 minutes. You can also make a pretty awesome sore throat reliever by combining sage and thyme. Take an ounce of both grind them, and cover them with 16 ounces of apple cider vinegar. Be sure to shake it periodically and let it sit for ten days before using.