New genetic insights into brainstem glioma, a rare and deadly form of childhood and young adult brain cancer, have been published jointly by researchers and neurosurgeons in Duke Medicine and their collaborators in China.
Their publication says that a genetic mutation, which occurs in the tumor cells, contributes to the growth and the death of cells and also to the tumour’s resistance to radiation.
The findings have both immediate and long-term implications. Straight away, patients may be spared radiation as it is probably rendered ineffective by the mutation. In the longer term, the mutation would serve as a strong candidate for drug development.
Genetic tests conducted by the scientists revealed that a number of the tumor cells had a mutation in a gene called PPM1D, enabling them to defy natural death and proliferate wildly. The fact that this mutation is the force behind the development of brainstem gliomas was unknown thus far.
The more common mutation to the TP53 gene, a tumor suppressor that is linked to half of all cancers, is absent in tumors having the PPM1D mutation. Senior author Hai Yan, MD, PhD, a professor of pathology at Duke University School of Medicine says that the “finding has immediate clinical applications.” Because we now know that because of either PPM1D or TP53 mutation the tumour becomes “resistant to radiation,” patients can be spared this treatment approach.”
“Since the finding have given us a clue as to why these tumors grow inappropriately, they may help us to design better treatments,” said co-author Zachary Reitman, MD, PhD, a research associate at Duke. Work on new treatments capable of targeting the PPM1D genetic mutation and arresting its cancer-growing capabilities is already on at Yan’s lab.
“Because the gene mutation causes cells to avoid death and proliferate, PPM1D is itself a target for drug development ” Yan said. “Drugs that can switch off this growth function are simpler to develop than drugs that can switch on the cell’s defective tumor suppression mechanism.”