Researchers have long pinned hopes on biological indicators—or molecular biomarkers—to serve as tools to help clinicians identify populations at risk, classify tumor types, or monitor disease progression in cancer, which is diagnosed in an estimated 11 million people worldwide each year. Genes have held the spotlight for many years as potential biomarkers of cancer, but increasingly, researchers are turning to individual proteins or groups of proteins and their modifications with the belief that these molecules hold secrets to cancer pathophysiology.
Because protein modifications can be extremely diverse (leading to a large number of isoforms) and proteins cannot be amplified like DNA can, they don't always offer a clear molecular distinction between a cancer patient and healthy control. "There are several difficulties in the study of proteins that are not inherent in the study of nucleic acids," writes William Cho, a scientific officer in clinical oncology at Queen Elizabeth Hospital in ...
