A specific protein that switches on the process that releases cancer cells from the original tumor and allows the cells to spread and develop into new tumors in other parts of the body, has been discovered by researchers.
Boffins reported the finding of disabled-2 (Dab2) in Nature Cell Biology.
The process called epithelial-mesenchymal transdifferientiation (EMT) has been known to play a role in releasing cells (epithelial cells) on the surface of the solid tumor and transforming them into transient mesenchymal cell: cells with the ability to start to grow a new tumor.
This is often the fatal process in breast, ovarian, pancreatic and colon-rectal cancers.
Searching to understand how the EMT process begins, Ge Jin, who has joint appointments at the Case Western Reserve University School of Dental Medicine and the Lerner Research Institute at the Cleveland Clinic, began by working backwards from EMT to find its trigger.
The researchers found that a compound called transforming growth factor-beta (TGF-beta) triggers the formation of the Dab2 protein. It was this protein, Dab2, that activated the EMT process.
He discovered that when the researchers knocked out Dab2, EMT was not triggered.
"This is the major piece in cancer research that has been missing," Jin said.
Most tumors are epithelial in origin and have epithelial markers on their surface. The EMT process takes place when some of those cells dislodge from the surface and undergo a transformation into a fibrous mesenchymal cell maker with the ability to migrate.
"EMT is the most important step in this process," said Jin. He was part of a six-member research team, led by Philip Howe from the Department of Cancer Biology at the Lerner Research Institute in a National Cancer Institute-funded study.