Researchers say they may have a new therapy for the same brain cancer that Sen. John McCain died from in 2018, which may have found a way around how the tumor grows and persists.The potential novel therapy targets the circadian clock of glioblastoma, a tumor that penetrates brain tissue and hides from radiation, chemotherapy and surgical treatments, according to a study published Tuesday in Cancer Discovery.
Researchers say that targeting the circadian rhythm of stem cells left behind after surgery, radiation and chemotherapy could help to prevent it from coming back.
Each year, the rare, evasive and usually fatal disease kills roughly 15,000 people. People normally develop glioblastoma in their mid-60s and go on to live an average of 15 months after diagnosis.
"We think this is opening the door to a whole new range of therapies," said Steve Kay, a researcher at the University of Southern California and study author, in a news release. "It's a great example of collaboration and convergence."
Glioblastoma is hard to treat because the tumor regenerates from leftover stem cells. The circadian clock is made up of protein molecules that control the growth, replication and damage repair of cells throughout the human body. When a person has their clock sped up or slowed down, it can bring on cancer.
In lab experiments, the researchers noticed how the circadian clocks boosted the metabolism of the glioblastoma stem cells. This strengthened the cells, allowing them to easily block out normal therapies.
To break through this resistance, the researchers used a small molecule drug to attack the circadian clock, which then slowed down the metabolism, killing the stubborn stem cells.
"This lays the groundwork for us to explore this as a novel therapy for glioblastoma," Kay said. "In the near future, we're going to do more work with animal models of the tumor and compare our new drug with the current standard of care. Perhaps we can one day contribute towards meeting this terrible unmet medical need."