Posted on 06/21/2005 3:53:57 PM PDT by Tumbleweed_Connection
A common virus that is harmless to people can destroy cancerous cells in the body and might be developed into a new cancer therapy, U.S. researchers said on Tuesday.
The virus, called adeno-associated virus type 2, or AAV-2, infects an estimated 80 percent of the population.
"Our results suggest that adeno-associated virus type 2, which infects the majority of the population but has no known ill effects, kills multiple types of cancer cells yet has no effect on healthy cells," said Craig Meyers, a professor of microbiology and immunology at the Penn State College of Medicine in Pennsylvania.
"We believe that AAV-2 recognizes that the cancer cells are abnormal and destroys them. This suggests that AAV-2 has great potential to be developed as an anti-cancer agent," Meyers said in a statement.
He said at a meeting of the American Society for Virology that studies have shown women infected with AAV-2 who are also infected with a cancer-causing wart virus called HPV develop cervical cancer less frequently than uninfected women do.
AAV-2 is a small virus that cannot replicate itself without the help of another virus. But with the help of a second virus it kills cells.
For their study, Meyers and colleagues first infected a batch of human cells with HPV, some strains of which cause cervical cancer.
They then infected these cells and normal cells with AAV-2.
After six days, all the HPV-infected cells died.
The same thing happened with cervical, breast, prostate and squamous cell tumor cells.
All are cancers of the epithelial cells, which include skin cells and other cells that line the insides and outsides of organs.
"One of the most compelling findings is that AAV-2 appears to have no pathologic effects on healthy cells," Meyers said.
"So many cancer therapies are as poisonous to healthy cells as they are to cancer cells. A therapy that is able to distinguish between healthy and cancer cells could be less difficult to endure for those with cancer."
AAV-2 is being studied intensively as a gene therapy vector -- a virus modified to carry disease-correcting genes into the body. Gene therapy researchers favor it because it does not seem to cause disease or immune system reaction on its own.
I hope you are correct and I am totally wrong. Perhaps I'm just a bit cynical.
Just as I suspected.
fyi
Actually, only about 20 to 25% of people (in the USA) will ever get cancer of any kind in their lifetimes. Also, the article stated that the virus kills cancers of the epithilial cells, which covers many, but not all, types of cancers.
I saw this yesterday.
Is it too good to be true!?
Good to get good news.
"Although the reason why remains unclear, population-based studies have shown that people who carry AAV2 tend not to develop human papillomavirus- (HPV-) associated cervical cancer. In general, AAV2 requires association with a helper virus in order to replicate. When it finds a helper virus, such as HPV, AAV2 disrupts the life cycle of the host and induces apoptosis, a type of cell death.
"one of the ways AAV2 suppresses cancer is by inhibiting the normal process of DNA duplication of human papillomavirus (HPV). HPV is known to lead to cervical cancer. A second way AAV2 suppresses cancer is linked to its ability to slow cell-cycle progression by decreasing cancer cell proliferation rates and causing growth arrest."
http://www.eurekalert.org/pub_releases/2005-06/ps-shv062105.php
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