AsianScientist (Oct. 25, 2011) – Scientists from Germany, USA, Switzerland, and Australia have identified a new biochemical mechanism that allows brain tumors to survive and grow, offering hope of new drug treatments for some of the most aggressive tumors.
The research, led by Professor Michael Platten from the Department of Neurooncology at the University Hospital of Heidelberg, was recently published in the journal Nature.
Gliomas, the most common and aggressive type of brain tumor in both adults and children, progress rapidly and the median survival time of patients is less than a year. The survival time for patients with gliomas, particularly the more aggressive tumours such as glioblastoma multiforme, has not changed in decades despite changes in therapeutic approaches.
In the study, the international team identified the key role played by kynurenine, a by-product of the metabolism of the essential amino acid tryptophan, in favoring brain tumor growth and at the same time suppressing anti-tumor immune response.
The researchers were also able to identify the receptor expressed by tumor cells that kynurenine acts through – the aryl hydrocarbon receptor (AhR).
While particularly relevant in the development and persistence of gliomas, the kynurenine pathway also has a role in other brain cancers, and is implicated in other neurodegenerative diseases.
Associate Professor Guillemin, a co-author on the study, said the breakthrough could potentially lead to viable therapeutics for a range of conditions, including Alzheimer’s disease, motor neuron diseases, multiple sclerosis and Parkinson’s disease.
“We are currently looking at all the molecules deriving from the tryptophan metabolism through the kynurenine pathway that can be linked to tumour persistence and immune suppression,” said Prof. Guillemin, who is head of the Neuroinflammation Group in UNSW’s School of Medical Sciences.
An oral drug able to block enzymes leading to kynurenine production has been developed and the drug could potentially be available for clinical trials within a few years, Prof. Guillemin said, and the mechanism elucidated here offers an entirely novel approach to therapy.
The article can be found at: Opitz CA et al. (2011) An endogenous tumour-promoting ligand of the human aryl hydrocarbon receptor.
——
Source: UNSW.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.
