The gene for the axonal cell adhesion molecule TAX-1 is amplified and aberrantly expressed in malignant gliomas

The human TAX-1 gene encodes a M-r 135,000 glycoprotein that is transiently expressed on the surface of a subset of neurons during development and is involved in neurite outgrowth, The TAX-1 gene has been mapped to a region o n chromosome 1 that has been implicated in microcephaly and the Van der Wou de syndrome. Using restriction landmark genome scanning to search for ampli fied genes in gliomas, we found TAX-1 to be amplified in 2 high-grade gliom as among a group of 26 gliomas investigated. Real-time reverse transcriptio n-quantitative PCR analysis detected high levels of TAX-1 mRNA in glial tum ors, even in the absence of TAX-1 gene amplification. Immunohistochemical a nalysis revealed abundant levels of TAX-1 in neoplastic glial cells of glio blastoma multiforme tumors, Because glial tumors are highly invasive and in view of the role of TAX-1 in neurite outgrowth, we investigated the potent ial role of TAX-1 in glioma cell migration, Using an in vitro assay, we fou nd that the migration of glioma tumor cells is profoundly reduced in the pr esence of either an anti-TAX-1 antibody or a TAX-1 antisense oligonucleotid e, Our findings suggest that TAX-1 plays a role in glial tumorigenesis and may provide a potential target for therapeutic intervention.