Intense cancer research is ongoing at UCLA’s Jonsson Comprehensive Cancer Center. One area of research is the growing interest in developing noninvasive methods to identify rare cancer cells or cancer cell DNA in blood. Current techniques remain complicated and are often extremely expensive. Now, UCLA researchers have developed a more effective approach to these “liquid biopsies” that has the potential to offer a streamlined and low-cost solution for cancer victims. The findings of the two-year study were published online on February 6 in the journal Oncotarget.
The study authors note that the technology creates millimeter-scale whirlpools to draw in and concentrate circulating tumor cells, known as CTCs, based on their size. CTCs are large, abnormal cells that are present in the circulation of cancer patients; they can be used as cellular markers of the disease. Analysis of these cells provides critical information regarding which treatments are best suited and most effective for a patient, and whether those receiving a therapy may relapse.
“CTCs are extremely rare, so isolating them is a problem similar to finding a needle in a haystack,” explained Dino Di Carlo, PhD, director of UCLA’s Jonsson Comprehensive Cancer Center Nanotechnology Program and professor of bioengineering at the UCLA Henry Samueli School of Engineering. He added, “Our filterless system avoids issues of previous technologies that clog and break cells apart, and we found this approach was more effective than technologies currently available at isolating cells from breast and lung cancer patients.”
For the study, the researchers isolated cells and detected specific proteins on these cells from 50 cancer patients. In a subgroup of these patients, they then compared the number of CTCs discovered by the FDA-approved gold standard instrument and found significantly higher numbers of cells per patient; more than 80% of patients had CTC levels above age-matched healthy individuals, compared to only 20% with the currently approved instrument.
In a 2014 study, the investigators discovered that the micro-whirlpools, or vortices, entrapped cancer cells with epithelial characteristics in a small number of patients (epithelial cells help to protect or enclose organs within the body). The new findings revealed that almost half of the CTCs isolated with this new Vortex HT system developed by UCLA researchers did not have epithelial-like markers and that the number of CTCs isolated in the same time was almost doubled compared to the previous iteration of the technology.
Dr. Di Carlo noted that he hopes the new system will enable clinicians to better understand how to administer and monitor treatments and that over the long-term such an approach could potentially be used to detect cancer much earlier with a simple blood test.