CHARLOTTESVILLE, Va. (CBS19 NEWS) -- A new discovery about human papillomavirus, or HPV, could lead to new treatments for cervical cancer and other cancers that are caused by it.
Researchers at the University of Virginia School of Medicine have been working on this project.
According to a release, HPV is responsible for almost all cases of cervical cancer and 95 percent of anal cancers.
It is also the most common sexually transmitted disease, infecting more than 79 million people in America, most of whom do not know they are infected and could be spreading it.
"Human papillomavirus causes a lot of cancers. Literally thousands upon thousands of people get cervical cancer and die from it all over the world," said researcher Anindya Dutta, PhD, of the UVA Cancer Center. "Cancers of the mouth and anal cancers are also caused by human papillomaviruses. Now there's a vaccine for HPV, so we're hopeful the incidences will decrease. But that vaccine is not available all around the world, and because of religious sensitivity, not everybody is taking it. The vaccine is expensive, so I think the human papillomavirus cancers are here to stay. They're not going to disappear, so we need new therapies."
Scientists do understand how HPV causes cancers by producing a protein that shuts down a healthy cell's ability to prevent them, but efforts to block one of those proteins, called oncoprotein E6, have so far proven unsuccessful.
Dutta and his fellow researchers have found the virus takes the help of a protein already present in human cells, an enzyme called USP46, which then become essential for HPV-induced tumor formation.
The researchers say that enzyme could be very susceptible to drugs.
"It's an enzyme, and because it's an enzyme, it has a small pocket essential for its activity, and because drug companies are very good at producing small chemicals that will jam that pocket and may enzymes like USP46 inactive," added Dutta. "So we are very excited by this possibility that by inactivating USP46 we'll have a way to treat HPV-caused cancers."
The release says HPV uses the enzyme for an activity that is opposite to what the oncoprotein E6 was known to do, which is recruit another cellular enzyme to degrade the cell's tumor suppressor.
The new findings show E6 uses USP46 to stabilize other cellular proteins and prevent them from being degraded.
Both of these E6 activities are critical to the growth of cancer.
The researchers add the enzyme is specific to HPV strains that do cause cancer, and it is not used by other strains of the virus that do not cause cancer.
The findings have been published in the scientific journal Molecular Cell.