Tiny “Blood Biopsy” Device May Improve Cancer Diagnosis

Cell nuclei predict metastasis

A team of investigators at the Cedars–Sinai Medical Center and the University of California–Los Angeles is using a new blood-analysis technique and a tiny experimental device to help physicians predict which cancers are likely to metastasize by identifying and characterizing tumor cells circulating in the blood.

The scientists are conducting “liquid biopsies” by running blood through a postage-stamp-sized chip with nanowires 1,000 times thinner than a human hair and coated with antibodies, or proteins, that recognize circulating tumor cells. The device, the NanoVelcro Chip, works by “grabbing” circulating tumor cells that break away from tumors and travel through the bloodstream looking for places in the body to spread.

Use of the chip in liquid biopsies could allow doctors to regularly and easily monitor cancer-related changes in patients, such as how well they’re responding to treatment, according to the researchers.

“It’s far better to draw a tube of blood once a month to monitor cancer than to make patients undergo repeated surgical procedures,” said co-lead investigator Edwin Posadas, MD. “The power of this technology lies in its capacity to provide information that is equal to or even superior to traditional tumor sampling by invasive procedures.”

Although some forms of prostate cancer are so slow-growing that they pose little risk to patients, other forms of the disease are lethal. Identifying which patients have which type of the disease has become a crucial area of study because prostate cancer is one of the leading causes of cancer death among men in the U.S. Nearly 27,000 U.S. men are expected to die from the disease in 2017, according to the American Cancer Society.

The research team has determined that in certain cancer cells, the nucleus is smaller than in other, more-typical cancer cells. Patients with the most-advanced cases of aggressive prostate cancer have cells with these very small nuclei.

The investigators also found that very small nuclei are associated with metastasis to the liver and lungs in patients with advanced prostate cancer. Those nuclei developed before the metastasis was detected. Identifying very small nuclei in early disease progression may help pinpoint which patients have a high risk of developing cancer that can spread and be fatal, according to the researchers.

For the past five years, Posadas and his colleague, Hsian-Rong Tseng, PhD, have collected blood samples from cancer patients to profile and analyze the circulating tumor cells and other components. That process has helped them understand how prostate and other cancers evolve. The two investigators and their teams hope that their findings will contribute to developing effective, targeted treatments for many types of cancer.

“Minimally invasive methods to both diagnose and follow cancer through simple blood tests offer a unique and novel approach that can lead to earlier diagnosis and treatment, leading to more cures,” said Robert A. Figlin, MD, deputy director of the Samuel Oschin Comprehensive Cancer Institute at Cedars–Sinai.

Source: Medical Xpress; February 13, 2017.