Saturday, February 7, 2009

Saturday....February 7th...2009

Avastin...Linda's big helper......

How is Avastin Thought to Work?

In order to grow and spread, tumors need a constant supply of oxygen and other nutrients. Tumors get this supply by creating their own network of blood vessels. This process is called angiogenesis (an´-gee-o-jen´-i-sis). To start angiogenesis, a tumor sends out signals to nearby blood vessels. These signals cause new blood vessels to grow toward the tumor. Once these new vessels reach the tumor, they provide the supply of blood that brings oxygen and other nutrients to the tumor. This helps the tumor grow.

Avastin: an anti-angiogenic agent

A tumor creates a network of blood vessels—a process called angiogenesis.

An anti-angiogenic agent may inhibit blood vessel formation, which starves the tumor.

Avastin is thought to work by blocking one of the key signals that causes angiogenesis. Specifically, Avastin blocks a protein called vascular endothelial growth factor (VEGF, for short). This may allow Avastin to affect the tumor in different ways:

* Avastin may cause the blood vessels to shrink away from the tumor, blocking the supply of oxygen and nutrients that the tumor needs

* Avastin may also cause the existing blood vessels to change in ways that help the chemotherapy reach the tumor more effectively

* Finally, Avastin may interfere with the growth of new blood vessels, potentially helping to block further growth and spread of the cancer

What is a targeted therapy?

The phrase “targeted therapy” is often used to distinguish between treatments like Avastin and chemotherapy. Chemotherapy affects all cells that divide rapidly. Because tumor cells are constantly dividing, chemotherapy may be effective against tumors. However, some healthy cells may also divide rapidly. Chemotherapy can affect these cells too, and this can cause some of the side effects that people experience with these types of drugs.
Targeted therapies treat cancer in a different way. Because of this, the side effects of Avastin can be different than those of chemotherapy. Avastin is a particular type of targeted therapy called anti-angiogenic therapy, and it is given with chemotherapy. Anti-angiogenic therapy helps block the growth of new blood vessels that provide nutrients to the tumor.

Monoclonal antibodies and biologic therapy
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You may also hear Avastin called a monoclonal antibody or a biologic therapy. Antibodies are proteins made naturally by the body's immune system that help identify and fight foreign substances. Scientists in a lab can make many copies of one kind of antibody. Because they are “clones” of a single type, these lab-made antibodies are described as “monoclonal antibodies.” In cancer therapy, monoclonal antibodies are used to target specific substances in the body that help cancer cells grow. Avastin targets a substance that is known to help tumors grow a new network of blood vessels. Because monoclonal antibodies (proteins) are made from natural substances in the body, they are also sometimes called biologic agents

2 comments:

Anonymous said...

Very interesting. What an education we are getting on this Blog......No pop quizes, now, Dave. I know you like to keep us on our toes.
Marilyn

Anonymous said...

Wow I have taken physiology and anatomy and Med terminology, but this is very interesting, and technical. I appreciate the break down of the process. I am a visual and audio learner so this really helped me. I read words and try to put a picture to it. Good Job David, I think I have a visual, on the way the medications are going to heal. I really am praying for for you guys and a speedy recovery.
Love Ya, Vicky