Researchers at the National Institutes of Health (NIH) recently identified a master switch protein linked to cancer that is also involved with normal fetal growth. Studying models of rapid growth of cells that occur in healthy fetal developed helped NIH scientists to determine that the E2F3 protein acts as a master switch. This protein switch can, in turn, activate a major growth promoting gene, IGF2, instructs the building of insulin-like growth-factor-2 protein that has increases in many cancers. http://www.nichd.nih.gov/news/releases/Pages/040913-IGF2.aspx
The insulin-like growth factor 2 protein plays an essential role in growth and development before birth and promotes the growth and division (proliferation) of cells in many different tissues. There is data on more than 200 growth factors that are common in fetal development that support rapid fetal growth and which gradually switch off as the body ages.
During fetal development, typically only the paternal copy of the IGF2 gene is active, a process known as genetic imprinting. In some cancers, both the copies of the gene become active, increasing the amount of insulin-like growth factor 2 produced. This loss of imprinting (LOI) phenomenon results in high amounts of insulin-like growth factor 2 that could stimulate tumor cell growth. Loss of imprinting of the IGF2 gene is associated with many types of cancer, including cancer of blood-forming cells (leukemia) and cancers of the breast, prostate, lung, colon, and liver. http://ghr.nlm.nih.gov/gene/IGF2
“We’ve long known that some of the genes that promote rapid growth in prenatal and early postnatal life become reactivated in cancer cells,” said Dr. Baron. “Now we’ve identified a molecular switch that appears to turn on some of these genes, taking us a step forward in understanding normal body growth and the abnormal growth in some types of cancer.” http://www.nichd.nih.gov/news/releases/Pages/040913-IGF2.aspx
Prior research into cancer showed that some of these fetal growth genes could be switched back on in adults and increased in certain cancers. The discovery of the E2F3 protein is key to understanding the process of reactivating growth of cells into cancers of the bladder, prostate and childhood cancers. http://ghr.nlm.nih.gov/gene/IGF2
Relevant to the advancement of cancer diagnosis and therapy is that this E2F3 protein switch may be act as a master controller that limits body growth. http://www.pnas.org/content/110/15/6181.short One goal for cancer research is being able to use gene markers to detect cancer onset. The ultimate goals are finding therapeutic approaches to managing E2F3 expression and safely dim this master switch and prevent cancer and metastasis. http://www.wpi.edu/Pubs/E-project/Available/E-project-042612-111106/unrestricted/Neil_Crawford_MQP_Final.pdf