Researchers have created a small implant that successfully captures early circulating cancer cells in mice – a development they say could lead to new strategies to reduce cancer progression in humans.
Study co-author Prof. Lonnie Shea, of Northwestern University Feinberg School of Medicine in Evanston, IL, and colleagues publish the details of their creation in Nature Communications.
When cancer cells migrate away from the primary tumors and spread to other parts of the body, this is known as metastatic cancer.
Most commonly, cancer cells circulate through the bloodstream to reach other areas, but they can also travel through the lymph system. These circulating cancer cells bind to the wall of a blood or lymph vessel and make their way to a new organ, where they can start new tumors.
Cancer patients are much more likely to survive the disease if circulating cancer cells are spotted early, before they have spread to other organs. However, Prof. Shea and colleagues say it is challenging to do so.
The team explains that circulating cancer cells are present in low numbers in the blood, often residing there for long periods before inhabiting a new site, while some of the cancer cells are shed in early tumor progression, making their detection difficult.
Implant entices circulating cancer cells before ‘trapping’ them
In their study, the researchers describe how they created a “biomaterial implanted scaffold” that identifies and captures metastatic cancer cells.
Created using poly(lactide-co-glycolide), or PLG – a microporous biomaterial approved by the US Food and Drug Administration (FDA) for a variety of pharmaceutical applications – the implant works by recruiting immune cells that entice circulating cancer cells, before “trapping” them.
An imaging technique called inverse spectroscopic optical coherence tomography (ISOCT) is then applied, allowing researchers to distinguish between healthy cells and cancer cells that have been trapped by the implant.
The researchers tested the implant in eight mice with metastatic breast cancer. Two implants around 5 mm (0.2 inches) in diameter were inserted either under the skin or into the abdominal fat of each mouse.
The team found the implants successfully captured circulating cancer cells in the mice, reducing the number of these cells in the bloodstream and, in turn, reducing the likelihood of them starting tumors at new sites.
For example, they say mice that received the implants had a much lower abundance of cancer cells in their lungs, compared with a group of mice with cancer that did not receive the implants.
While their study was only conducted in mice, the researchers believe their implant has potential as a therapeutic tool to reduce cancer progression in humans. They add:
“Taken together, the early detection, reduced burden of metastatic disease and potential to apply targeted therapies afforded by this technology could significantly extend the time to disease progression.”
Talking to BBC News, Prof. Shea said the team is hoping to test the implant in human trials soon.
“We need to see if metastatic cells will show up in the implant in humans like they did in the mice,” he explained, “and also if it’s a safe procedure and that we can use the same imaging to detect cancer cells.”
Medical News Today recently reported on a study in which researchers from the University of California-San Francisco identified a mutation in a deadly form of brain cancer called desmoplastic melanoma that allows it to escape attack from the immune system. The team says the discovery may hold hope for immunotherapy as a cancer treatment.
Written by Honor Whiteman