University of Arizona study links Y chromosome loss to cancer risk

A study led by Dr. Dan Theodorescu at the University of Arizona Cancer Center suggests that the loss of the Y chromosome in men may serve as an early indicator of cancer development. Published in JCI Insights, the research indicates that mosaic loss of the Y (mLOY) creates a pre-neoplastic field effect, establishing a zone of genetic vulnerability in tissues that appear normal under a microscope.

Researchers analyzed 1,000 tissue samples from 405 men, using automated fluorescent imaging to inspect over 4.3 million cell nuclei. The team identified a genetic gradient where Y-to-X chromosome ratios shifted from normal tissue to early abnormal cells, culminating in full-blown cancer. This progression was particularly evident in bladder tissue mapping.

The study found that this pattern of chromosome loss is not limited to a single area but is observed across multiple organs, including the colon, rectum, esophagus, pancreas, and lungs. Dr. Theodorescu noted that finding LOY in normal-appearing tissues adjacent to tumors suggests it could act as both a biomarker and a mechanism contributing to the formation of cancer.