Blood Clues: Proteins Predict Cancer 7 Years in Advance

Researchers have identified specific proteins in the blood that may signal the presence of cancer more than seven years before diagnosis. The scientists discovered 618 proteins associated with 19 types of cancer, including bowel, prostate, and breast cancers.

Among these proteins, 107 were found in individuals whose blood was collected at least seven years before they were diagnosed with cancer. These proteins could potentially be targeted for cancer prevention, shifting the focus from detection to prevention, and with further research, they could lead to the development of drugs that stop cancer before it begins.

The two studies, funded by Cancer Research UK and conducted by Oxford Population Health, suggest that these proteins might play a role in the early stages of cancer development and could indicate an increased risk of the disease. Early detection through these proteins could enable treatment at an earlier stage or even prevent cancer altogether.

Professor Ruth Travis, a senior molecular epidemiologist at Oxford Population Health and a senior author of the studies, emphasized the importance of understanding the factors driving the earliest stages of cancer to prevent it. She noted that these studies provide new insights into the causes and biology of various cancers, highlighting what happens years before a cancer diagnosis.

Dr. Iain Foulkes, executive director of research and innovation at Cancer Research UK, highlighted the significance of finding early molecular signals for preventing cancer. He stated that this painstaking research is crucial for developing preventative therapies, which aim to extend and improve lives by eliminating the fear of cancer.

In the first study, researchers analyzed blood samples from the UK Biobank, which included samples from more than 44,000 individuals, 4,900 of whom were later diagnosed with cancer. They used proteomics, the study of proteins, to analyze 1,463 proteins in a single blood sample from each person. By comparing the proteins in those later diagnosed with cancer to those who were not, the researchers identified proteins linked to cancer risk, finding 182 proteins that varied in the blood three years before diagnosis.

The second study involved analyzing genetic data from over 300,000 cancer cases to determine which blood proteins were involved in cancer development and could be targeted by new treatments. They identified 40 proteins in the blood that influenced the risk of nine types of cancer, including bladder, breast, endometrial, head and neck, lung, ovarian, pancreatic, kidney, and malignant non-melanoma cancers.

The findings suggest that altering these proteins could change the likelihood of developing cancer, although it may also lead to unintended side effects. The researchers stress the need for further investigation to determine the exact role of these proteins in cancer development, identify the most reliable ones for testing, develop clinical tests for detection, and find drugs that target these proteins.

Currently, the Galleri test, which detects circulating tumor DNA in the blood, is being trialed in the NHS. Researchers propose that the newly discovered proteins could be used for cancer prevention, emphasizing the ongoing need for prevention and early detection to improve cancer survival rates.

The findings are published in the Nature Communications journal.