Device Predicts Tumor Spread by Sorting Traveling Cancer Cells

Cancer researchers and doctors are interested in methods that analyze circulating tumor cells because they offer ways to determine how aggressive tumors are without having to do biopsies.

Devices that capture circulating tumor cells from the blood of cancer patients currently are in use, but they cannot differentiate among the different types of tumor cells — they simply count them all. They do, however, give an indication of tumor aggressiveness — the more circulating tumor cells there are, the higher the chance the cancer is spreading. But they cannot determine, for example, whether a sample contains a high or low proportion of more aggressive tumor cells.

In the journal Angewandte Chemie, Shana Kelley, a professor at the Leslie Dan Faculty of Pharmacy at the University of Toronto in Canada, and colleagues write about a new device they have developed that sorts circulating tumor cells.

Team members describe how they used nanoparticles to tag the circulating tumor cells, then used the device to sort them into discrete subgroups based on their “phenotype” or observable molecular characteristics to provide a snapshot of the tumor cells present in the blood of cancer patients.

“In the lab, we were able to demonstrate that the tool was not only highly effective at differentiating these cells, but also proved to be more sensitive than the current leading methods of cellular sorting,” Kelley said.

In their study, Kelley and her team, with collaborators at the Sunnybrook Health Sciences Centre, also in Toronto, and the London Health Sciences Centre in London, Ontario, tested the new device on samples collected from 20 patients with localized prostate cancer.

Researchers found significant levels of circulating tumor cells in all the patients. But not all the samples had the same mix — the subpopulation profiles were quite varied — despite the fact the patients had all received very similar clinical diagnoses.

Although their study only involved a small number of patients, the group now plans to test the device with samples from patients with breast, colon, ovarian, lung and pancreatic cancers.

Kelley is hoping the research will show that the sensitive technology in the device has the potential to provide useful information about circulating tumor cells, leading to better diagnoses and improved outcomes for patients.

“As a result, we are excited to pursue new research opportunities in an effort to more accurately and less invasively diagnose and improve the health outcomes for cancer patients,” she added.