A better way to detect cancer early

A new, multiparameter approach developed at the Weizmann Institute of Science may lead to a blood test that will diagnose cancer with unprecedented accuracy. This research, from the lab of Dr. Efrat Shema of the Department of Immunology and Regenerative Biology, was published in September 2022 in Nature Biotechnology.

The idea for diagnosing cancer using liquid biopsies arose from the fact that blood contains free-floating DNA and proteins shed by dead blood cells in healthy people – and in cancer patients, by dead tumor cells as well. “Some of the byproducts of cell destruction, including cancer DNA and proteins, are dumped into the bloodstream, and we know how to collect and analyze them,” Dr. Shema says.

“Eliminating the discomfort means that people would be less likely to avoid getting tested – and more likely to have their cancers detected earlier,” says Vadim Fedyuk, who led the study together with fellow graduate student Nir Erez.

Using a single-molecule imaging method that Dr. Shema developed as a postdoctoral student at Harvard Medical School, Fedyuk and Erez, together with colleagues, compared the nucleosomes in the blood of 30 healthy individuals with those of 60 patients with different stages of colorectal cancer.

In collaboration with Prof. Guy Ron from the Racah Institute of Physics at the Hebrew University of Jerusalem, the scientists combined what they had revealed about the molecular biology of cancer with artificial intelligence algorithms, applying machine learning to the large data sets obtained from the two groups. The analysis was performed not only on all these cancer markers but on combinations of and relationships between them as well. To make sure their findings are not limited to colorectal cancer, the scientists also applied their technology to compare blood nucleosomes of healthy volunteers with those of 10 patients with pancreatic cancer.

“Our algorithm could tell the difference between the healthy and the patient groups at a record level of certainty for studies of this type – with 92 percent precision,” Dr. Shema says. The scientists call the new technology EPINUC, an acronym for “epigenetics of plasma-isolated nucleosomes.”

Dr. Efrat Shema’s research is supported by the Henry Chanoch Krenter Institute for Biomedical Imaging and Genomics, and the Swiss Society Institute for Cancer Prevention Research. Dr. Shema is the incumbent of the Lisa and Jeff Aronin Family Career Development Chair.