What makes aggressive brain cancer 'immortal?'
A new study has discovered what makes glioblastoma cells so resilient and difficult to destroy. The finding may lead to more effective, targeted treatments in the future, the researchers argue.
Scientists from the University of California, San Francisco have recently investigated why a very aggressive and often treatment-resistant type of brain cancer, called glioblastoma, is "immortal."
They explain that it all starts with a mutation in TERT promoters, which influence when the TERT gene is activated.
TERT is one of the genes that encode the telomerase complex.
The activity of telomerase, a specialized protein, is important when it comes to regulating the length of telomeres. These are structures that "cap" the ends of chromosomes, or molecules found in the nuclei of most cells, which carry genetic information.
Telomeres' role is to stop DNA material contained in the chromosomes from unraveling. However, every time a cell divides, telomeres will become shorter and shorter until they are no longer functional. This also determines the end of a cell's life.
Telomerase works by prolonging telomeres, thus ensuring the continued life of a cell. Yet normally, telomerase is active in very few cells; usually the stem cells of human embryos, thereby allowing them to continue to grow and develop in the womb.
The scientists explain that the cells of many types of cancer are able to imitate the mechanism of stem cells thanks to mutations in the TERT gene, which allows them to continue living for an indeterminate period of time.
However, they also add that recent studies have pointed out that over 50 types of cancer may access "immortality" not through mutations of the TERT gene, but through mutations of TERT promoters — and glioblastoma is one of them.
