A new therapeutic alternative has been found for children who suffer from a malignant pediatric tumor bone and soft tissue called Ewing’s sarcoma, according to preclinical evidence.
Researchers have combined two anti-tumor agents, olaparib and trabectedin. In animal models, this combination has improved the sensitivity of cancer cells to these drugs and seems to lead to increased effects. In fact, they have been observed complete remission of cancer in 100% of cases. The study results were published in Oncotarget.1
Ewing’s sarcoma is the second most common bone cancer and affects children and youth. Currently, if diagnosed early and there is no metastasis it can be cured in 80% of cases but between 25% and 30% of cases are diagnosed when it has metastasized and survival drops to 20%.
“Our results demonstrate that the combination of trabectedin and olaparib could be a new therapeutic strategy that should be studied in greater depth so that it can benefit patients with this disease in the near future,” said Enrique de Alava, MD, PhD, director of the Unit Management Clinical Pathology Virgen del Rocio Hospital and Molecular Pathology group at Instituto de Biomedicina de Sevilla in Spain.
It has been observed as Ewing’s sarcoma cells need to keep repairing mechanisms of DNA damage in good condition to survive and continue to divide.
“Trabectedin, however, causes breaks and abnormal DNA structure of the cancer cell, which induces cell death. Olaparib works on the same line, blocking the action of a gene (PARP1), whose function is to repair DNA damage when it detects lesions,” explained Oscar Martínez Tirado, PhD, the head of the Sarcomas group of the Bellvitge Biomedical Research Institute (IDIBELL) in Spain.
The combination of both drugs is synergistic and much more powerful than the effect achieved with the application of each drug individually.
1. Ordóñez JL, Amaral AT, Carcaboso AM, et al. The PARP inhibitor olaparib enhances the sensitivity of ewing sarcoma to trabectedin. Oncotarget. May 27, 2015. [Epub ahead of print]