1. Engineering Viruses to Fight Cancer
Virotherapy
Engineering Viruses to Fight Cancer
Miles Carmody
11/17/09
ITMG

2. Beginnings and History
Earliest reports were from an Italian gynecologist in 1912 using
More tests in late 1940’s early 1950’s
Tests on both animals and humans
Dropped because of effectiveness of chemotherapy and lack of advances in technology

3. Beginnings and History
At the end of the 20th century, there were progressions in the field of virotherapy which led to more research
These studies have advanced virotherapy to what it is today

4. What is Virotherapy?
Virotherapy is the use of genetically altered viruses to treat cancer.
To do this scientists create oncolytic viruses; viruses whose genetic makeup has been altered to combat cancer
Oncolytic viruses are built to seek out cancer and destroy it; they serve no other function

5. How Does Virotherapy Work?
Oncolytic viruses are engineered with different ways to be useful. They can enter cancer cells and multiply until the cell bursts…

6. How Does Virotherapy Work?
They can enter cancer cells and destroy the cell’s ability to multiply…

7. How Does Virotherapy Work?
They can be built to only attach to cancer cells, not healthy ones…
Notice the receptor-binding-protein attaching only to the cancer cell on the right.

8. How Does Virotherapy Work?
Or they can be built so that they can only replicate in cancer cells, not healthy cells.
Notice the RNA matching with the of the cancer cell at the bottom right, but not that of the healthy cell at the bottom left.

9. Advantages and Disadvantages of Virotherapy
More efficient than radiation and chemotherapy
The same strengthening of the immune system the viruses’ produce that helps fight the cancer can also serve to expel the viruses from the body
Kills fewer healthy cells
There is a risk of the virus mutating
Is less damaging to bone marrow
The cancerous tumor might adapt to the virus, limiting it’s effectiveness
Can effect a broader spectrum of cancer
It has been difficult to get enough of the virus to the tumor mass before the immune system attacks
Is very efficient at both finding and killing cancer cells
Possible for viruses to remain dormant unless host is cancerous
Possible to engineer viruses that cannot survive without cancerous cells
The viruses’ presence can strengthen the immune system, increasing the body’s cancer fighting potential

10. Current Research
Biovex has just raised $40 million for the development of new drugs.
The company has commenced phase III tests on their new drug OncoVEX.
OncoVEX works specifically with melanoma.
Viralytics is a public, anti-cancer company that has developed numerous virotheraputic drugs.
Cavatak has been tested and lab animals and noted to destroy melanoma cells.

11. Current Research
Oncolytics has developed a drug called REOLYSIN, which is now being tested for use on head and neck cancers.
The company continues to grow and it just bought a new drug company.
They’ve completed nine human based trials.
Sunway Biotech is a firm based in China.
They currently have oncolytic virus based drugs on the market in China.
Another drug is about to be sold which focuses on head and neck cancers.

12. References
Nettelbeck, Dirk M., and David T. Curiel. "Tumor-Busting." Tumor-Busting (2003): Abstract. Scientific America (2003).
-Kelly, Elizabeth, and Stephen J. Russell. "History of Oncolytic Viruses: Genesis to Genetic Engineering." Molecular Therapy (2007): 1-8