Starvation for brain tumour cells
Primary brain tumours are highly aggressive and prone to resistance to therapy. Recent advances enable tumour sensitisation to radiation-induced death but this is not always effective in practice. Other challenges of RT include systemic toxicity, poor penetration of the brain and relative sensitivity of normal brain tissue versus tumour tissue. Despite these drawbacks, RT remains a cornerstone of available treatment. The RECURRENT GLIOMA TX project aimed to investigate the combination of RT and a new epigenetic modulator, vorinostat. However, due to unavailability of the drug, the team turned their attention to the effects of energy metabolism in brain tumours. Normal and cancer cells obtain their energy in different ways and brain tumour cells in particular are dependent on glucose. Starved of the sugar, brain tumour cells grow very poorly and are very sensitive to radiation. In an eight-week clinical trial, patients received an anti-diabetic drug or had a very low carbohydrate diet, or both. Treatment response was measured with brain magnetic resonance imaging scans and metabolic profiles. The trial is ongoing and preliminary results are promising. Early results indicate radiation-resistant cells demonstrate increased expression of anti-apoptotic variants of key proteins in the DNA-damage response pathway, explaining their resistance to radiation-induced cell death. Of critical importance, the researchers discovered that metabolic manipulation was able to reverse this phenotype. Although not possible to conclude that dietary intervention conclusively improves cancer outcomes, RECURRENT GLIOMA TX research results suggest that cancer prognosis could be improved with changes in diet. This study, along with others worldwide, stands to provide evidence-based conclusions for a new holistic approach to cancer treatment involving diet along with other treatments.
Keywords
Brain tumour cells, diet, radiation therapy, RECURRENT GLIOMA TX, clinical trial