Potential Therapeutic Effects of Phytochemicals and Medicinal Herbs for Cancer Prevention and Treatment

Cancer has a major impact on society across the world. It is one of the major causes of death, with approximately 1.7 million new cases expected to be diagnosed in the United States and 600,000 people will die from the disease. Worldwide statistics in 2012 reported over 14 million new cases and 8.2 million cancer-related deaths. New cases are expected to rise by about 70% over the next 20 years. The current standard of care, surgery, chemotherapy, and radiation has not proved to be highly effective and comes with significant side effects and costs. Although conventional cancer therapy can target certain cancer cells and sometimes prevent relapse of the illness, complementary and alternative therapies are required due to disadvantages of the current therapies such as low effectiveness, adverse effects, or availability. Moreover, a number of studies have found adjunctive therapeutic approaches to improve outcomes for cancer patients. One potential complementary method with conventional cancer drugs involves the use of medicinal herbs and phytochemicals. The possible therapeutic benefits include, but are not limited to antiproliferative, apoptotic, anti-metastatic, and anti-angiogenic effects, of which have been demonstrated in in vitro experiments and some clinical trials; more clinical trials need to be done. This review summarizes some plant sources exhibiting anti-cancer and chemoprevention activity. An overview of how phytochemicals and medicinal herbs permit the prevention and ultimate removal of cancer cells with minimal trauma to the host will be presented