Synchrotron used to improve cancer treatment

Traditional cancer treatment tablets and injections deliver cancer-killing drugs indiscriminately to all parts of the body, often causing serious side effects.

That’s why University of Saskatchewan student Masoomeh Poorghorban is designing a new nano-sized way to carry a cancer drug right to the diseased cells.

The pharmacy PHD student is the first U of S student to use the Canadian Light Source synchrotron to design a drug delivery system, placing her at the forefront of an emerging field.

The Canadian Institutes of Health Research have awarded her $84,000 over four years for the work.

“The synchrotron provides this wonderful chance for us,” she said. “Every day we evaluate drugs, and the X-ray beam allows you to see these tiny details nothing else does.” Researchers at the U of S are developing a skin cancer drug that causes minimal damage to the surrounding healthy cells. But an effective drug isn’t enough if it can’t make it to the cell.

“There are so many good drugs but with a big problem — they’re not soluble in water,” Poorghorban said.

Since the human body is 60 to 70 per cent water, this means non-soluble drugs can’t get anywhere in the body on their own.

Photo by Scott Bell

Poorghorban’s work gets around this problem by using a protective carrier for the drug to get it to the cancer cells, like water in a bucket or water balloon. The carrier also needs to have a bit of fat to attach to fatty skin cells and drop off the drug, so the drug delivery system is like a bucket with a fatty handle.

She has already used the synchrotron to find an appropriate drug delivery molecule, or “bucket,” to fit the drug. This molecule, which allows the drug to slip into a human cell, is 1,000 times smaller than a human skin cell.

To determine whether the carrier and drug are a good fit, shape and structure are vital. Poorghorban and a group of CLS researchers aim synchrotron X-rays at a crystal — in this case, the drugcarrying “bucket.” Then they observe how the beam gets scattered, which allows them to reconstruct the molecule.

“We get a picture of the molecule atom by atom,” Poorghorban said.

As fit depends upon how the drug and carrier interact at a molecular level, the researchers will use synchrotron X-rays to observe how the carrier bucket and drug attach and release from one another.

The final step will be to engineer and connect a fatty handle to the bucket, which will be attracted to skin cells and pull the drug inside, delivering the treatment.

This combination will also be studied using synchrotron techniques.

“I think the synchrotron is the future of most pharmaceutical drug development. It’s awesome because there are no boundaries between the sciences,” she said.

For instance, her two project supervisors — Ildiko Badea of the college of pharmacy and nutrition and Pawel Grochulski at the Canadian Light Source — bridge the gap between two very different fields: Pharmacy and physics.

Poorghorban, who came to the U of S from Iran to pursue her studies, wants to move into industry work after this project, using her valuable synchrotron research experience.

She has a few years left on the design project, but the research will continue much longer.

“Drug discovery is a lengthy process. It takes 10 to 15 years to get a new drug on the market,” Badea said.

This article first ran as part of the 2011 Young Innovators series, an initiative of the U of S Research Communications office in partnership with the Saskatoon StarPhoenix.