Identification and characterization of a novel cancer/testis antigen gene CAGE.
We applied serological analysis of cDNA expression library technique to identify cancer-associated genes. We screened cDNA expression libraries of human testis and gastric cancer cell lines with sera of patients with gastric cancers. We identified a gene whose expression is testis-specific among normal tissues. We cloned and characterized this novel gene. It contains D-E-A-D box domain and encodes a putative protein of 630 amino acids with possible helicase activity. It showed wide expression in various cancer tissues and cancer cell lines. The corresponding gene was named cancer-associated gene (CAGE). PCR of human x hamster Radiation Hybrids showed localization of CAGE on the human chromosome Xp22. Transient transfection of CAGE showed predominantly nuclear localization. Both Western blot and plaque assay indicated seroreactivity of CAGE protein. We found that demethylation played a role in the activation of CAGE in some cancer cell lines that do not express it. Cell synchronization experiments showed that the expression of CAGE was related with cell cycle. This suggests that CAGE might play a role in cellular proliferation. Because CAGE is expressed in a variety of cancers but not in normal tissues except testis, this gene can be a target of antitumor immunotherapy.
Cho
Bomsoo
B
Cancer Genomics Division, In2Gen Company, Seoul 110-799, Korea.
Lim
Yoon
Y
Lee
Dae-Yeon
DY
Park
Sae-Young
SY
Lee
Hosoon
H
Kim
Woo Ho
WH
Yang
Hankwang
H
Bang
Yung-Jue
YJ
Jeoung
Doo-Il
DI
D000236:Adenoma / Q000235:genetics* / Q000276:immunology; D000595:Amino Acid Sequence; D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D034961:Antigens, Nuclear; D001483:Base Sequence; D002277:Carcinoma / Q000235:genetics* / Q000276:immunology; D002453:Cell Cycle / Q000502:physiology; D006224:Cricetinae; D053487:DEAD-box RNA Helicases; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D016415:Sequence Alignment; D013274:Stomach Neoplasms / Q000235:genetics* / Q000276:immunology; D013737:Testis / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured; D014960:X Chromosome
D000951:Antigens, Neoplasm; D034961:Antigens, Nuclear; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; C454199:DDX53 protein, human; D053487:DEAD-box RNA Helicases