Biomarkers in Mice and Men Identified

Clinically relevant trace proteins, or biomarkers, are leaked by tumours into the blood. Since every protein is different, each has the equivalent of a distinguishing molecular “bar code.” The goal is to identify protein signatures that are only present in cancer, which may then serve as biomarkers in screening blood tests to detect early disease.

Investigators from Massachusetts General Hospital, University of Michigan and Belfer Institute for Innovative Cancer Science at Dana-Farber Cancer Institute collaborated on the research. For this study, the researchers first analysed blood samples from genetically engineered mouse models of pancreatic ductal adenocarcinoma at both early and late stages of tumour development. Of nearly 1,500 proteins identified in these mice, five were associated consistently with a precancerous condition known as pancreatic intraepithelial neoplasia, or PanIN, which, if left untreated, eventually progresses to full-blown pancreatic cancer.

The researchers then sought to determine whether the same biomarkers turned up in blood samples obtained from 30 recently diagnosed pancreatic-cancer patients. They also looked for the biomarkers in 13 people with asymptomatic, early-stage pancreatic cancer. To compare, the researchers analysed blood from 20 healthy and 15 people diagnosed with chronic pancreatitis.

The five-biomarker panel, if developed into a screening test, may be particularly useful when combined with a currently available test that measures a pancreatic-cancer biomarker called CA19.9, which is elevated in 80 percent of newly diagnosed patients but is not linked to asymptomatic, early-stage disease.

Both together may improve the detection of early-stage disease prior to the onset of symptoms and may also help better distinguish between cancer and pancreatitis, a noncancerous, inflammatory condition, so the scientists hope.; Source: Fred Hutchinson Cancer Research Center