FISHing for answers

FISHing for answers

A new diagnostic technology could revolutionize cancer testing and treatment
September 2, 2009
Linda Pilarski
Linda Pilarski

University of Alberta (U of A) researchers have developed a cancer-testing technology with a snappy name but a serious purpose.

The “FISH on a chip” is a complex test that detects abnormalities in chromosomes which characterize particular types of cancer. To create it, researchers miniaturize a conventional diagnostic test called FISH (fluorescent in situ hybridization) onto a microfluidic chip, allowing them to make a diagnosis using extremely small fluid volumes. The resulting “laboratory on a chip” promises to turn what, until now, has been a rare and expensive test into a routine part of cancer treatment — one that could target individual cancers and spare patients needless suffering.

The FISH test involves attaching fluorescent dyes to chromosomes to detect cancer-promoting breaks and reattachments. These abnormalities provide clinicians with critical information about disease outcomes and treatment options.

“The biggest benefit of this test is to ensure patients get the right treatment in a timely manner,” says Linda Pilarski, a researcher at the U of A and a Canada Research Chair in Biomedical Nanotechnology. “If research has shown that a particular chromosome abnormality is associated with a bad outcome or a lack of response to particular drugs, then you want to know that. Patients shouldn’t have to suffer side effects from a treatment that can’t help them, and they want treatment that can target their particular cancer.”

Pilarski has worked with Christopher Backhouse, a professor in the U of A’s department of electrical and computer engineering, to develop FISH on a chip. Backhouse’s lab has produced progressively smaller and less expensive instruments to ultimately create a portable device with the technological wherewithal of a major medical diagnostics facility.

The FISH test is particularly applicable to blood cancers, including myeloma, leukemia and lymphoma, which account for about 20 percent of all cancers. But Pilarski says it could also potentially play a role in diagnosing prostate cancer and in helping determine whether, for example, Herceptin — an expensive drug used to treat certain types of breast cancer — is likely to be effective.

Currently, conventional FISH tests are rarely conducted in Canada outside of research hospitals and clinical trials, since each one costs $2,000 or more, and multiple tests are usually needed to achieve a reliable diagnosis. The test, which requires expensive lab space and highly skilled technologists, can also take several days to complete.

Because the miniaturized version requires fewer reagents — the chemical solutions used to cause a reaction and detect other substances — 10 FISH-on-a-chip tests can be done for as little as $100. And the tests can be completed in less than a day. Another critical advantage is that FISH-on-a-chip technology is more portable than conventional testing and could be made available to patients in rural and remote areas.

Pilarski and her colleagues are continuing to refine the technology while looking for commercial sponsors to help take their invention into the medical marketplace, where she is certain there is a healthy appetite for FISH on a chip.

“As an oncology researcher, I understand the clinical demand for more accessible and affordable diagnostic systems,” says Pilarski. “Doctors want to treat their patients with the most effective therapy possible. I believe this technology is an important step in that direction.”