A new USC study has found evidence that targeting CD47, a protein that is part of the innate immune system, could be a key step in fighting colorectal cancer. It is one of the first indications that targeting part of the innate immune system, combined with traditional immunotherapy drugs which work on the adaptive immune system, could be more effective in fighting colorectal cancer. In the present study researchers analyzed DNA and RNA from 14,287 colorectal cancer tumors, comparing tumors with higher levels of CD47 expression to those with lower levels. The researchers found that higher levels were linked to more aggressive tumors, more activated cancer pathways and more immune cells inside the tumor. The findings suggest that developing an immune checkpoint inhibitor drug that can block the activity of CD47 could improve outcomes for colon cancer patients, many of whom are not well served by existing immunotherapy drugs.