A molecular biologist, Dr. Ana Marisa Chudzinski-Tavassi, at the Instituto Butantan in Sao Paulo, is directing a group of colleagues who are exploring the possibility that a protein found in tick saliva, and identified as Factor X active, may be able to selectively destroy cancer cells.

Researchers were studying the anti-coagulent properties of tick saliva—when a tick bites a host, human or otherwise, their saliva helps stop the blood from clotting and thus allows the tick to continue feeding. Because a similar protein inhibits cell growth, researchers wondered if the Factor X active might behave in a similar fashion.

First the researchers had to collect enough tick saliva—no mean feat in itself, since it involved positioning gorged ticks over minute straws to collect the salivia, then creating a way to convince yeast cultures to reproduce the protein.

Next, Chudzinski-Tavassi's group tried applying the protein to tumors on text animals. The results were promising:

"If I treat every day for 14 days an animal's tumor, a small tumor, this tumor doesn't develop—it even regresses. The tumor mass shrinks. If I treat for 42 days, you totally eliminate the tumor" Dr. Chudzinski-Tavassi reported.

This is a long way from being a possible cure; but it at least is a promising avenue of research.