The Cancer Research UK Grand Challenge brings together the very best researchers from around the globe to unite their talent, pool resources and crack the biggest questions in cancer research. Matthew L. Meyerson, MD, PhD (Damon Runyon Fellow '95-'98) of the Dana-Farber Cancer Institute, Boston, and Wendy S. Garrett, MD, PhD (Damon Runyon Fellow '06-'09) of the Harvard T.H. Chan School of Public Health, Cambridge, received £20 million to lead an international, multidisciplinary team of researchers focusing on the microbiome and its role in colorectal cancer. The microbiome is composed of the trillions of different microorganisms including bacteria, fungi and viruses that inhabit the human body and differs from person to person. By the end of the project, they aim to revolutionize the understanding of the role the microbiome plays in cancer development, find new ways to prevent colorectal cancer and define new treatment strategies through manipulating the gut microbiome.