Another way olive leaf helps to fight cancer is through its antiviral activity/. Keeping in mind that most cancers have been linked to viral infections.
Long before olive leaf became popular in the AIDS community to fight HIV, also a cancer virus, olive leaf's primary use was as a sedative, meaning it could also help with things such as high blood pressure as well. The AIDS community then discovered that olive leaf was also a source of natural protease inhibitors that inactivated viruses like HIV, formerly known as human T-cell leukemia/lymphoma virus type 3 (HTLV-3). A few years later olive leaf started being promoted for many other conditions such as various infections.