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watch One-Minute World News Last Updated:  Tuesday, 11 March,
2003, 00:02 GMT Ricin cancer therapy tested Castor beans Ricin
is extracted from castor beans Doctors may have found a way of
harnessing the destructive power of ricin to fight cancer
without potentially lethal side-effects.  Ricin, extracted from
castor beans, is a powerful natural toxin and considered a
potential biological weapon.  Scientists want to use it to kill
cancer cells, by joining it to a protein that binds onto
lymphoma cells.  There is no doubt that there is real potential
for immunotoxins Dr David Flavell, University of Southampton
However, some patients given the experimental treatment
developed a symptom called "vascular leak syndrome", which
affects blood vessels, particularly in the lungs.  However, a
team from the University of Texas Southwestern Medical Center
believe they have found a way to genetically modify the toxin so
that it is less dangerous to humans - but st