Researchers from Penn State University have identified a molecule which, when introduced to the TRAIL protein, causes cancer cells to "commit suicide".
For nearly two decades, scientists have been aware that a protein known as TRAIL (tumour-necrosis-factor-related apoptosis-inducing ligand) causes a process called apoptosis. Apoptosis occurs when the nuclear DNA of a cell become fragmented, causing the cell to self destruct and "commit suicide".
TRAIL occurs naturally as part of our immune system and has been shown to be quite effective in causing apoptosis in cancer cells. Wafik El-Deiry, an oncologist at Pennsylvania State University, explains:
TRAIL is a part of our immune system: all of us with functional immune systems use this molecule to keep tumors from forming or spreading, so boosting this will not be as toxic as chemotherapy.
Although researchers have proven that TRAIL is an effective treatment for some cancers, it had limitations. Unable to cross the blood-brain barrier, it was not a practical treatment in more hard to treat cancers. However, Penn State researchers have found a single molecule known as TIC10 can trigger the production of the TRAIL protein and eliminate the previous limited uses.
El-Deiry, a Penn State researcher, explains that TIC10 is effective because it is much smaller than the proteins that have previously been tested, which makes it capable of crossing the blood–brain barrier that separates the main circulatory system from the brain, He tells Eureka Alert:
Using a small molecule to significantly boost and overcome limitations of the TRAIL pathway appears to be a promising way to address difficult to treat cancers using a safe mechanism already used in those with a normal effective immune system. This candidate new drug, a first-in-its-class, shows activity against a broad range of tumor types in mice and appears safe at this stage.
He continued by saying:
We didn't actually anticipate that this molecule would be able to treat brain tumours — that was a pleasant surprise.
TIC10 appears to work on a wide range of other cancerous tumors, including breast, lymphatic, colon and lung cancer, causing those cancer cells to enter apoptosis. It also appears to trigger healthy, non cancerous cells to create the TRAIL protein as well. According to El Deiry:
TIC10 activates the TRAIL gene not only in cancerous cells, but also in healthy ones. This gives it enormous potential to create a 'bystander effect', in which apoptosis - or cell death - is induced in cancer cells immediately next to healthy ones. Healthy cells are also stimulated to increase the amount of TRAIL receptors on their cell surface. These receptors can then bind to the adjacent cancerous cells, triggering their demise. It's almost like TRAIL-plus - it does so much more.