Tick Saliva, Hope of Brazilian Scientists for Curing Cancer

By Dialogo
August 31, 2009

SÃO PAULO, 28 August 2009 (AFP) - Tick saliva contains a protein that could cure skin, liver, and pancreatic cancer, according to Brazilian researchers. Upon studying a South American variety of this blood-sucking parasite, Amblyomma cajennense, they discovered that this protein destroys cancerous cells and preserves healthy ones. “It’s a great discovery,” in the opinion of the study’s director, Ana Marisa Chudzinski-Tavassi, a researcher in molecular biology at the Butantan Institute in São Paulo. “The substance contained in this tick’s saliva (...) could be the cure for cancer,” she declared to AFP. The researcher said that she discovered the virtues of this protein, baptized ‘Active X Factor,’ by chance when testing the anticoagulant properties of the tick’s saliva. These properties allow the parasite to ingest blood - including human blood - without it coagulating. The protein has characteristics in common with a common anticoagulant known as TFPI or as a Kunitz-type inhibitor, which also has an effect on cell growth. The hypothesis that this protein could have an effect on cancerous cells led to laboratory tests that surpassed all expectations. “To our surprise, it did not kill the normal cells,” said Chudzinski-Tavassi. “But it did kill all the cancerous cells in the test,” she added. In her modest laboratory at the institute, the researcher collects the saliva from rows of immobile ticks by placing straw under their heads. The saliva obtained in this way was used in tests on laboratory rats with cancer. The results have been more than promising. “If I treat an animal that already has a tumor, a small tumor, every day for fourteen days, the tumor does not develop and even shrinks. The tumorous mass diminishes. If I treat it for forty-two days, the tumor is completely eliminated,” the scientist affirmed. Producing a medicine based on this discovery, nevertheless, will require years of clinical trials and a significant financial investment, two things that Brazil cannot currently offer. Chudzinski-Tavassi has applied for a patent on the tick saliva and is presenting her team’s discovery in medical publications and at conferences around the world. However, she affirms that going beyond her laboratory “proof of concept” will be very difficult. “Discovering this is one thing. Turning it into a medication is something completely different,” she declared.