Researchers from the University of Southern California demonstrated in breast and colorectal cancers that a technique for determining a tumor’s immune signature could be useful for diagnosing and treating specific cancers.
While the genetic variations that comprise an immune signature are complex, the team found that a small subset of genes is integral in explaining immunological behavior.
Using real-time PCR, the scientists screened tumors to identify 14 proimmunity genes and 11 anti-immunity genes. They studied the expression of these genes in five mouse tumor models for breast cancer, leukemia, colon cancer, lung cancer, and renal cell carcinoma. They then compared two of these immune signatures with corresponding human tumors, eight cases of human ductal carcinoma, and 11 cases of colorectal cancer.
Remarkably, the researchers found that the immune signatures of each of the human breast cancer cases nearly matched that of mice. In all cases, the researchers saw a suppression of CD83 and CD28, two genes that affect activation of immune cells, and over-production of B7-H4, a gene whose protein product inhibits immune activation. The human colorectal cancers, however, showed variations in their immune signatures. The investigators saw this as an indication of the need to understand the signature for each patient’s individual cancer.
The research appeared in the July 1 issue of Clinical Cancer Research.