Study results from Antoni van Leeuwenhoek Hospital, Division of Immunology provide new insights into oncology

02-09-2007

A report, "TRAIL enhances efficacy of radiotherapy in a p53 mutant, Bcl-2 overexpressing lymphoid malignancy," is newly published data in Radiotherapy and Oncology. "Resistance to apoptosis is a contributing factor in the response to radiotherapy. Aim of this study was to evaluate whether TRAIL--in a soluble isoleucine zippered form--enhances the cytotoxic effect of irradiation on tumor cells with a blockade in the mitochondrial apoptosis route and/or a dysfunctional p53 pathway. The p53 mutant human T acute lymphoblastic leukemia line Jurkat transduced with the Bcl-2 gene was used as model system in vitro and in a subcutaneous transplant setting in immunodeficient mice," scientists in Amsterdam, Netherlands report.

"Sensitivity to single and combined treatment was read out by apoptosis hallmarks and clonogenic survival in vitro, and by bioluminescence and palpation in vivo. Jurkat cells overexpressing Bcl-2 did not undergo apoptosis after irradiation, but the combination with TRAIL synergistically induced apoptosis without breaking mitochondrial resistance. TRAIL also reduced clonogenic survival after irradiation. In vivo, radiotherapy or TRAIL alone delayed tumor outgrowth, but combination treatment had the most profound effect," wrote E.H. Wissink and colleagues, Antoni van Leeuwenhoek Hospital, Division of Immunology.

The researchers concluded: "Isoleucine zippered TRAIL can strongly enhance the efficacy of tumor therapy with ionising radiation in an unfavourable setting of p53 mutation and Bcl-2 overexpression."

Wissink and colleagues published their study in Radiotherapy and Oncology (TRAIL enhances efficacy of radiotherapy in a p53 mutant, Bcl-2 overexpressing lymphoid malignancy. Radiotherapy and Oncology, 2006;80(2):214-22).

For more information, contact E.H. Wissink, Antoni van Leeuwenhoek Hospital, Division of Immunology, Netherlands Cancer Institute, Amsterdam, Netherlands.

Publisher contact information for the journal Radiotherapy and Oncology is: Elsevier Science Ireland Ltd., Customer Relations Manager, Bay 15, Shannon Industrial Estate, Co. Clare, Ireland.

This article was prepared by Hospital Law Week editors from staff and other reports. Copyright 2007, Hospital Law Week via NewsRx.com.