| Chemotherapy and radiation are very ineffective | | | | melanoma. Burd commented that quercetin is similar |
| when being used on melanoma skin cancer or | | | | to precursors of melanin, and so tyrosinase identifies |
| glioblastoma multiforme brain cancer. The department | | | | and stimulates quercetin to a pro-oxidant rather than |
| of nutritional sciences at the University of Arizona has | | | | an antioxidant. Quercetin, when it is tested with |
| a very intense interest in both forms of cancer and | | | | melanoma tumor-cell cultures, the tumor cells die. This |
| wants to find how quercetin, a natural, | | | | happens because the melanoma enzyme is tricked |
| biologically-active compound is capable of sensitizing | | | | into stimulating so much quercetin that it changes and |
| the cancerous tumors to treatment and not harm | | | | sensitizes the cancerous melanoma cells to the |
| normal tissue. This research has become very | | | | chemotherapy drug and dies. In this situation, |
| important as the occurrence of melanoma, often a | | | | quercetin is acting as a biological response modifier. A |
| fatal form of skin cancer, is growing at the rate of | | | | response modifier is a drug or a chemical compound |
| three percent per year according to the American | | | | acting to change the function of tumor cells to make |
| Cancer Society. | | | | them more responsive to chemotherapy or radiation. |
| The standard chemotherapeutic drug used to treat | | | | Burd's team is now analyzing a group of bioactive |
| melanoma cancer has been proven ineffective over | | | | food and plant substances to see if they can find out |
| the years of use when used by itself. Randy Burd, | | | | if they will kill tumor cells for different cancers. If |
| assistant professor of nutritional sciences and a | | | | they do, they want to discover the genes or |
| member of The University of Arizona BIO Institute, | | | | proteins involved in this action. Successful compounds |
| and his team are testing the drug, as well as its new | | | | like the quercetin used in the melanoma study, need |
| analog Temozolomide. They are being tested with a | | | | to be modified by scientists so they can be made |
| variety of biochemical backbones and plant | | | | into functional pharmaceutical drugs. This will make |
| compounds. They then analyzed the enzymes | | | | the compounds more influential and each of them can |
| involved in their activation. They worked with COX-2 | | | | be tested in clinical trials. The goal of this work is to |
| inhibitors and found they each had their own | | | | find quercetin combinations so they can design a |
| complications so they started looking at quinones, | | | | specific therapy for each cancer type that has been |
| which can be found in nature as pigments, vitamin | | | | successful in their research. |
| biochemical backbones and plant compounds. | | | | Glioblastoma multiforme brain cancer research has |
| Quercetin is a polyphenol that is found in fruits and | | | | one fundamental focus and that is to find and screen |
| vegetables, a quinone, and it has demonstrated it has | | | | quinones which can be used in the brain to reverse |
| an exciting effect on melanoma tumors. If quercetin | | | | the radiation-resistance of tumors. Those compounds |
| is used in low concentrations, it acts as an antioxidant | | | | would then be in conjunction with radiation treatment. |
| but if it is used in high concentrations, it changes to a | | | | This approach is new and much has to be done |
| cell-damaging pro-oxidant. The study is taking | | | | before they are ready to develop successful |
| advantage of this pro-oxidant character of quercetin. | | | | pharmaceutical drugs. |
| Burd's team is using tyrosinase as a highly expressed | | | | DISCLAIMER: I am not a Doctor and do not give |
| enzyme responsible for the pigment formation in | | | | medical advice; this is a news report and cannot |
| human skin cells which grow out-of-control in | | | | substitute for the advice of a medical professional. |