It is known that radiotherapy is effective in damaging brain tumors, but radiotherapy does not fully kill the tumor because the cancer cells can repair themselves and keep living. Researchers at Sidney Kimmel Cancer Center are now testing a combination of radiotherapy and a drug called panobinostat that makes the cancer cells unable to repair themselves. The researchers are testing the combination on aggressive, recurrent brain cancer. They feel that panobinostat makes radiotherapy much more effective.
Currently, there is no standard treatment for gliomas other than radiation. Most patients will not live very long. The efficacy of panobinostat is hopeful for improving survival rates.
Panobinostat was approved for use in 2015 for treatment of multiple myeloma, and now it is being tested to treat other cancers. It is a histone deacetylase inhibitor; it works by modifying RNA to change protein production and turns off RAD51 (a DNA repair enzyme) which upsets cancer growth.
Researchers found that the highest doses of panobinostat were well tolerated and improved survival. Overall, researchers found that this cancer drug was very safe and that there is promise to treat other drugs.
The question I will pose is: If the drug works by changing protein production and turning off DNA repair enzymes, wouldn’t you think it would cause bad side effects? Yet it was shown to be very safe at even the highest doses.
Wenyin Shi, Joshua D. Palmer, Maria Werner-Wasik, David W. Andrews, James J. Evans, Jon Glass, Lyndon Kim, Voichita Bar-Ad, Kevin Judy, Christopher Farrell, Nicole Simone, Haisong Liu, Adam P. Dicker, Yaacov R. Lawrence.Phase I trial of panobinostat and fractionated stereotactic re-irradiation therapy for recurrent high grade gliomas. Journal of Neuro-Oncology, 2016; DOI:10.1007/s11060-016-2059-3