Chondrosarcoma Associated Gene 2 (CSAG2)

The nucleotide sequence of the TRAG-3 cDNA contains an open reading frame of 333bp that predicts for a protein product of 110 amino acids. A GenBank search identifies a cosmid clone containing a genomic sequence corresponding to that of TRAG-3. DNA and protein analysis reveals that TRAG-3 has no homology to any known cDNAs or proteins. Northern analysis demonstrates that TRAG-3 is overexpressed in the taxol-resistant breast cancer cell line MDA 435TR as well as the doxorubicin-resistant multiple myeloma cell lines 8226/DOX40 and 8226/MDR10V. A survey of normal tissue shows minimal or absent TRAG-3 mRNA expression. Screening of a wide variety of cancer cell lines demonstrates TRAG-3 expression in many cell lines derived from different tissue types. TRAG-3 is a novel gene whose expression is associated with the chemotherapy-resistant and neoplastic phenotype.