Amplification and overexpression of TGIF2, a novel homeobox gene of the TALE superclass, in ovarian cancer cell lines.
Homeodomain transcription factors play important roles in directing cellular proliferation and differentiation. A TALE-superclass homeodomain protein, multifunctional repressor of TGFbeta-induced transcription. Here we report identification of TGIF2, a novel TALE-superclass homeodomain protein that shows distinct homology with TGIF, especially in its DNA-binding domain. TGIF2 is expressed ubiquitously in human tissues, with the highest levels being found in heart, kidney, and testis. The TGIF2 product contains a putative nuclear localization signal; translocation of the protein to the nucleus was confirmed by transfection of epitope-tagged cDNA. TGIF2 lies on chromosome 20q11.2-12. Since amplification of 20q is often observed among ovarian cancers, we determined the status of DNA copy-number and expression of TGIF2 in 14 ovarian-cancer cell lines. This gene was over-expressed in all lines that showed amplification by FISH analysis. The results suggested that TGIF2 may play an important role in the development and/or progression of some ovarian tumors through a mechanism of gene amplification.
Imoto
I
I
Department of Molecular Cytogenetics, Medical Research Institute, Tokyo, 113-8510, Japan.
Pimkhaokham
A
A
Watanabe
T
T
Saito-Ohara
F
F
Soeda
E
E
Inazawa
J
J
D000595:Amino Acid Sequence; D005260:Female; D005784:Gene Amplification; D015972:Gene Expression Regulation, Neoplastic; D005801:Genes, Homeobox; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D010051:Ovarian Neoplasms / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics; D016415:Sequence Alignment; D014407:Tumor Cells, Cultured
D018398:Homeodomain Proteins; D012097:Repressor Proteins; C414585:TGIF2 protein, human