A study has uncovered several new genetic mutations that could drive testicular cancer – and also identified a gene which may contribute to tumours becoming resistant to current treatments, reports Science Codex.
The study is the first to use state-of-the-art sequencing technology to explore in detail testicular germ cell tumours – which make up the vast majority of testicular cancers and are the most common cancers in young men. The study used whole-exome sequencing to examine tumor samples from 42 patients with testicular cancer treated at the Royal Marsden NHS Foundation Trust.
They uncovered a number of new chromosome duplications and other abnormalities that could contribute to the development of this cancer, as well as confirming a previous association with the gene KIT. Their study also found defective copies of a DNA repair gene called XRCC2 in a patient who had become resistant to platinum-based chemotherapy. They were able to verify the link between XRCC2 and platinum resistance by sequencing an additional sample from another platinum-resistant tumour.
Although generally testicular cancer responds well to treatment, resistance to platinum-based chemotherapy is associated with a poor long-term survival rate. The research provides a clue to why around 3% of patients develop resistance to platinum chemotherapy, as well as new insights into testicular germ cell tumours generally.
Dr Clare Turnbull, team leader in predisposition and translational genetics at The Institute of Cancer Research, London and honorary consultant in clinical genetics at The Royal Marsden NHS Foundation Trust said: "Our study is the largest comprehensive sequencing study of testicular tumours published to date, describing their mutational profile in greater detail than has been possible using previous technologies. We have identified new potential driver mutations for this type of cancer, and provided new evidence of a link between mutations in the gene XRCC2 and platinum treatment-resistant tumours. We now need additional studies with a larger number of patients, focusing in particular on platinum-resistant tumours, to help our discoveries lead to new options for those unlucky men whose cancer progresses in spite of the best available treatments."
[link url="http://www.sciencecodex.com/major_study_links_gene_to_drug_resistance_in_testicular_cancer-149328"]Full Science Codex report[/link]
[link url="http://www.nature.com/ncomms/2015/150122/ncomms6973/full/ncomms6973.html"]Nature Communications abstract[/link]