Transplant Envisioned The latest proposal involves transplanting a bacterial gene into a type of white blood cell that attacks tumors.

Angiogenesis inhibitors are promising candidates for attacking tumors by cutting off their blood supply.

A 2002 study showed that caffeine applied to the skin of mice may fend off skin cancer, attacking tumors before they fully form and healing the skin.

Biotech companies can customize antibodies to attack not only germs but also tumors or other disease-causing proteins.

Dr. Folkman has spent his career trying to prove that blocking angiogenesis could turn out to be an ideal therapy for attacking malignant tumors while leaving normal tissue intact.

Their findings, they say, open a new avenue for attacking tumors by thwarting the bone marrow's contributory role.

Several substances successfully attack tumors in mice but turn out to be useless in treating human cancers.

Vectibix, or panitumumab, is the first drug from Amgen that attacks tumors directly.

But during decades of experience, doctors had noticed that B.C.G. was a potent stimulant of local immune cells, including those that attack tumors, when injected in the skin.

But toxin chimeras should attack tumors more specifically, he said.