Cancer’s Defenses
Crushing
Vaccine approval
offers hope while
other armies muster
By Daniel Strain
Twirling globs of white blood cells circle a tumor like a Greek army ready to lay siege. These cells are used to winning — they take
down baddies such as viruses and bacteria on a daily basis. But cancer cells are
not an ordinary enemy. Like Troy, they
set up hefty barricades against attack,
often killing white blood cells or turning
them off on the spot. Too often, the
immune system loses this Trojan War.
But recent advances in therapeutic
cancer vaccine research may provide
the immune system with an offensive
edge. Such therapies aren’t the same as
the shots kids get before starting school
to prevent measles or polio. Nor are they
like antiviral vaccines, such as Gardasil,
that stave off infections which can lead
to cancer. Therapeutic cancer vaccines
wouldn’t prevent cancer, they would
treat it: training the immune system to
turn its forces on a tumor already in the
body with the skill of Achilles and the
strength of Ajax.
At least that has been the hope. For
about a decade, large clinical trials of
cancer vaccine candidates have turned
out mostly disappointing. But now a
handful of new therapies are showing
signs that the cancer vaccine effort could
be on the brink of big breakthroughs.
