Fatal brain cancer tamed by gene therapy
25 February 2008
From New Scientist
Rats with an aggressive form of human brain cancer have been successfully treated with gene therapy that "trains" the immune system to attack tumours.
The results could pave the way for human trials early next year, say researchers who developed the system at the Cedars-Sinai Medical Center in Los Angeles.
Previous attempts to treat glioblastomas with gene therapy failed because some tumour cells survived and regrew. The new treatment overcomes this problem by permanently priming the immune system to pick off any straggler tumour cells.
A harmless virus that only infects fast-dividing cancer cells is injected directly into the brain, and used to deliver the therapeutic genes into the tumour. One gene, HSV1-TK, kills the cancer cells by activating ganciclovir, an otherwise ineffective drug administered into the rat's abdomen. Yet the key to the therapy's long-term success is a second gene, Flt3L, which summons immune "dendritic" cells from the bloodstream into the brain.
These cells engulf the debris and transport it back to lymph nodes, where they re-prime the immune system to attack any remaining tumour cells during and after treatment. The work will appear in Molecular Therapy (DOI: 10.1038/mt.2008.18).
Cancer - Learn more about one of the world’s biggest killers in our comprehensive special
Kad se ova ideja prvi put pojavila pre nekih 10-15 godina, mnogi su prognozirali da ce uskoro doci do nove revolucije u tretmanu raznih obolenja. Medjutim, ispostavilo se da se krenulo suvise brzo u neke klinicke poduhvate i nakon jednog smrtnog slucaja, genetska terapija se morala vratiti na pocetak - tj. ponovnom izucavanju njenih osnova i poboljsanju virusa/vektora koji se koriste.
Najnovija istrazivanja na ovom polju sada vec obecavaju mnogo vise, a ovaj gore primer je samo jedan od njih.
