July 14, 2006 -- A common ingredient used to thicken everything from baby
food to sexual lubricants may help fight the virus that causes cervical cancerand genital warts.
Researchers found the thickener, carrageenan prevented human papilloma
viruses (HPV) from attaching to cells in laboratory tests. Certain strains of
HPV can cause cervical
cancer and genital
If more studies confirm these results, researchers say carrageenan-based
products may be developed and used to prevent HPV infection at low cost.
The FDA has recently approved a cervical cancer vaccine that targets HPV for
the prevention of cervical cancer in women at risk. But researchers say it
doesn't protect against every strain of HPV and costs about $360, which could
be too expensive for use in developing countries.
In the study, published in PLoS Pathogens, researchers found that
carrageenan, which is derived from red algae, fit the bill. Researchers say it
was an ideal candidate for testing because the thickener is already commonly
used in sexual lubricants and other topically applied products.
Normally HPV attacks cells by attaching to proteins on the cell surface and
then chemically getting access to the cells. But researchers found carrageenan
prevented infection by stopping the virus from attaching to the cells.
"We were floored by how much better it worked than anything else we have
tested. It's effective at 100-fold lower concentration than the next best
inhibitor we've found," says researcher John Schiller, senior investigator at
the National Cancer Institute, in a news release.
"Our results do not prove that carrageenans will work as a practical HPV
topical microbicide," cautions Schiller. "The potent inhibition of infection of
cells in dishes, coupled with the fact that carrageenan-based products are
already in use for genital application, are promising, but we will need to do a
well-controlled clinical trial before use of any of these products as an HPV
inhibitor could be recommended."