A novel way to reduce the genetic risk of prostate cancer has been identified by researchers from the University of Michigan Comprehensive Cancer Centre.
Typically, vaccines are based on specific antigens and trigger immunity for a specific pathogen.
It is challenging for cancer as the best lymphocytes that generate immunity to cancer are eliminated during development.
They sought to rescue key lymphocytes - called high affinity cancer-reactive T cells - during their development.
During the study, researchers showed that T cells involved in prostate cancer are deleted because of a gene called lymphotoxin alpha.
When the mice lacked lymphotoxin, these T cells came back. These mice become more resistant to prostate cancer. This result suggests that lymphotoxin can be a good target for immune prevention.
The researchers injected a protein targeting lymphotoxin into cancer-susceptible mice.
Without treatment, all of these mice will develop prostate cancer, and typically by age 6 months half of them will have metastatic cancer that has spread to distant organs. Although the treated mice still developed tumours, none developed metastases after 30 weeks.
"It appears that the rescued T cells delay tumour formation. It may not be that this approach can prevent cancer altogether, but it can delay the process and slow the aggressive growth and spread of cancer," said study author Dr Pan Zheng, associate professor of surgery and pathology at the U-M Medical School.
"There is a certain population with a high likelihood of getting cancer, and we need better strategies to minimize their risk.
This approach may be translated into clinical care for those patients," Zheng added.