In Translation

Dawn of a New Machine
(continued)

The work constitutes a giant step forward for the fields of human toxicology and cancer control. With the power of the AMS, Dingley traced the path of a realistic human dose of a potential carcinogen as it moves through a living human being. Dingley showed that the carcinogen rapidly reached a cancer site and lurked there for several days as it infiltrated and damaged DNA.

Realistic doses in real people. It’s a big improvement over the common way of testing a suspected carcinogen — giving megadoses of the substance to laboratory rodents, and waiting to see if the animals develop cancer.

Dingley is also using the AMS to look at cancer prevention: Can anti-cancer compounds, like those found in fruits and vegetables, help to prevent the kind of DNA damage caused by carcinogens like PhIP?

To find out, she fed various anti-cancer compounds — including isothiocyanates, found in broccoli and other cruciferous vegetables, and chlorophyllin, found in green, leafy veggies — to laboratory animals for two weeks. Then she gave the animals PhIP.
The AMS revealed that in animals pre-treated with the anti-cancer compounds, less PhIP reached the tissues, and less DNA damage was done.

“We found a sound, scientific reason why eating fruits and vegetables is good for you,” Dingley said.

In other AMS-based research, Turteltaub and Dingley are teaming up with David Gandara, associate director for clinical research at UC Davis Cancer Center, to trace chemotherapy drugs in the body.

The idea: to determine whether a chemotherapy drug is reaching a target tumor, and, if so, in what quantity.

The Accelerator Mass Spectrometer, or AMS.