Gene blockage may help treat childhood cancer

NEW YORK (Reuters Health) - Overactivity of a gene called ODC1 is associated with poor survival of neuroblastoma, a common, often fatal cancer seen mostly in young children, according to research presented Sunday at the American Association for Cancer Research 2008 meeting in San Diego.

The good news, however, is that blocking this gene may improve outcomes. In the study, the researchers gave an ODC1-blocking drug called DFMO to mice with the disease and actually cured some of them.

Dr. Michelle Haber of the Children’s Cancer Institute Australia in Sydney and colleagues analyzed neuroblastoma specimens from 209 patients before treatment and found that ODC1 overactivity predicted poor outcomes. “Patients with low levels of ODC1 in their tumors had significantly better survival,” Haber told the conference.

Moreover, patients with a variant of ODC1 associated with lower activity had better outcomes than patients without this variant, she reported.

“We’ve shown that ODC1 is a good target in primary neuroblastoma because the higher the levels of this gene, the worse the patients do,” Haber said.

Haber’s team also showed that inhibition of ODC1 with DFMO delayed or prevented the development of neuroblastoma in mice.

“Most importantly,” Haber said, the findings demonstrate that the effectiveness of standard chemotherapy drugs can be substantially improved by adding DFMO. In fact, when DFMO was combined with the chemotherapy drug cyclophosphamide, a number of the mice were cured of their cancer.

These findings suggest there is a new treatment approach for this childhood cancer, which has a very high relapse rate, she concluded.