HOUSTON -- An overexpressed gene found at the scene of a variety of tumors is implicated in the development of two types of malignant brain cancer in a paper by researchers at The University of Texas M. D. Anderson Cancer Center to be published in the Proceedings of the National Academy of Sciences. The paper will be posted online at the PNAS web site the week of July 2.
Just because a gene is associated with cancer doesnt mean that its actually causing cancer. In this paper we show for the first time that insulin-like growth factor binding protein 2 (IGFBP2) connects with two other proteins to fuel development and progression of brain tumors, says senior author Wei Zhang, Ph.D., professor in M. D. Andersons Department of Pathology.
Using a gene transfer delivery system in a mouse model, a team led by Zhang and Professor of Pathology Gregory Fuller, M.D., Ph.D., shows that IGFBP2 plays an active role in the tumorigenesis of astrocytoma and oligodendroglioma. Both cancers are forms of glioma, cancers that develop in the glial cells which normally support and nourish neurons -- that are highly resistant to treatment.
This makes IGFBP2 an important candidate for development of targeted therapy to treat gliomas, Zhang says. Gliomas kill about 13,000 people in the United States annually.
The possibilities are not limited to brain cancer, Fuller notes, because of the pervasive overexpression of IGFBP2 documented in other cancer types. The gene is expressed only at low levels in normal cells, which would potentially reduce side effects caused by a treatment that targeted the gene or its protein product.
Fuller and Zhang first associated overexpression of the gene with brain cancer in 1999. Other researchers have since found it to be overexpressed in prostate, ovarian, breast and colorectal cancers, some leukemias, and also in drug-resistant tumors.