In most cases, some brain tumors can prove to be quite arduous to completely eradicate, even following the best treatment. However, a group of researchers from Washington University School of Medicine in St. Louis, MO, have potentially discovered a means to cutting off the spear of brain tumors by examining the source by which the brain tumor stem cells regenerate.
“The discovery may help us attack the root of some of the deadliest brain tumors. A successful brain cancer treatment will very likely require blocking the tumor stem cells’ ability to survive and replenish themselves,” noted senior author and assistant professor of neurological surgery, Dr. Albert H. Kim.
Perhaps the deadliest forms of brain cancer is glioblastoma, a disease commonly referred to as “grow and go tumors” that occurs in approximately 18,000 people in the United States annually. Prognosis of those patients diagnosed with glioblastoma is seldom good; with the mean length of survival following diagnosis at only 15 months. Furthermore, only about 30 percent of patients with the deadly brain tumor survive for more than a period of 2 years. The treatment of glioblastomas commonly involves surgical resection as evidence points out that the more of a tumor that can be excisioned, the greater the survival outcome is for the patient. However, a great risk of damaging parts of the brain while removing a large portion of the tumor(s) remains a grave concern. What’s more, researchers have discovered that certain cells in glioblastomas in addition to other tumors are also quite resistant to the treatments of surgery, radiation, or chemotherapy. Therefore, it is these particular stem cells that are the primary factors behind the regeneration of tumors even after treatment has been administered.
“These tumor stem cells are really the kingpins of cancers, the cells that direct and drive much of the harm done by tumors,” said Kim.
However, in spite of their resiliency, the tumor stem cells may have a point of weakness in their dependence on a specific protein known as SOX2. This strand of protein is active in both brain tumor stem cells and healthy stem cells found throughout the body. Kim and his team discovered that by shifting the tumor stem cells to produce SOX2 using a second protein, CDC20, upping the levels of CDC20 as a result increased levels of SOX2. Yet while neutralizing CDC20 altogether resulted in the tumor stem cells being unable to generate SOX2 at all. The levels of SOX2 have a direct impact on the tumor stem cells’ capability to regenerate and form new tumors. Therefore, when levels of SOX2 increased so did the tumors ability to grow and vice versa.
“The rate of growth in some tumors lacking CDC20 dropped by 95 percent compared with tumors with more typical levels of CDC20,” said Kim.
In light of such significant discoveries, the team is now approaching various methods to completely obstruct CDC20 in brain tumors. Once current method being implemented is ribonucieic acid (RNA) interference, a method that obstructs the generation of certain proteins that is currently being utilized in clinical trials as a means of treatment for various diseases.
