Oct 20, 2011 - 1:38 pm
This is from this web site.http://www.chemocare.com/BIO/doxil.asp
"Doxil is an anti-cancer ("antineoplastic" or "cytotoxic") chemotherapy drug. It is the drug doxorubicin encapsulated in a closed lipid sphere (liposome). Doxil is classified as an "anthracycline antibiotic..." How Doxil Works: Cancerous tumors are characterized by cell division, which is no longer controlled as it is in normal tissue. "Normal" cells stop dividing when they come into contact with like cells, a mechanism known as contact inhibition. Cancerous cells lose this ability. Cancer cells no longer have the normal checks and balances in place that control and limit cell division. The process of cell division, whether normal or cancerous cells, is through the cell cycle. The cell cycle goes from the resting phase, through active growing phases, and then to mitosis (division).The ability of chemotherapy to kill cancer cells depends on its ability to halt cell division. Usually, the drugs work by damaging the RNA or DNA that tells the cell how to copy itself in division. If the cells are unable to divide, they die. The faster the cells are dividing, the more likely it is that chemotherapy will kill the cells, causing the tumor to shrink. They also induce cell suicide (self-death or apoptosis).Chemotherapy drugs that affect cells only when they are dividing are called cell-cycle specific. Chemotherapy drugs that affect cells when they are at rest are called cell-cycle non-specific. The scheduling of chemotherapy is set based on the type of cells, rate at which they divide, and the time at which a given drug is likely to be effective. This is why chemotherapy is typically given in cycles.Chemotherapy is most effective at killing cells that are rapidly dividing. Unfortunately, chemotherapy does not know the difference between the cancerous cells and the normal cells. The "normal" cells will grow back and be healthy but in the meantime, side effects occur. The "normal" cells most commonly affected by chemotherapy are the blood cells, the cells in the mouth, stomach and bowel, and the hair follicles; resulting in low blood counts, mouth sores, nausea, diarrhea, and/or hair loss. Different drugs may affect different parts of the body.Doxil is classified as an antitumor antibiotic. Antitumor antibiotics are made from natural products produced by species of the soil fungus Streptomyces. These drugs act during multiple phases of the cell cycle and are considered cell-cycle specific. There are several types of antitumor antibiotics:· Anthracyclines: Doxil, Daunorubicin, Mitoxantrone, and Idarubicin· Chromomycins: Dactinomycin and Plicamycin· Miscellaneous: Mitomycin and BleomycinDoxil is the drug doxorubicin encapsulated in a STEALTH® liposome. Liposomes are closed lipid spheres made of the basic components of natural human cell walls. The STEALTH® liposome have on their surface a substance to protect the liposome from detection by the body's immune system and to increase the time Doxil is circulating in the blood. By enclosing a drug in a STEALTH® liposome, scientists have shown that they are able to get close to the tumor and the encapsulated drug doxorubicin becomes available to work against the tumor cells.
Note: We strongly encourage you to talk with your health care professional about your specific medical condition and treatments. The information contained in this website is meant to be helpful and educational, but is not a substitute for medical advice.From Reuters Health Information"