Expression of MAGE-D4, a novel MAGE family antigen, is correlated with tumor-cell proliferation of non-small cell lung cancer.
OBJECTIVE
MAGE-D4, originally termed MAGE-E1, is a novel MAGE family gene that is expressed at high levels in malignant tumors as compared to normal tissue. The present study was conducted to assess the clinical significance of MAGE-D4 expression in non-small cell lung cancer (NSCLC).


METHODS
Expression of MAGE-D4 protein was estimated by immunohistochemistry and MAGE-D4 mRNA expression was investigated using quantitative reverse transcription-PCR (RT-PCR).


RESULTS
We assessed MAGE-D4 expression in NSCLC tissues and was found to be up-regulated in tumor tissues compared with normal lung tissues (mean MAGE-D4/GAPDH values, 0.035 for tumor tissues and 0.009 for normal lung tissues; p=0.002). However, there was no significant difference in MAGE-D4 expression among different pathological stages. The proliferative activity of tumor cells was significantly higher in high MAGE-D4 tumors (mean proliferative indices, 58.3 for high MAGE-D4 tumor levels and 34.0 for low MAGE-D4 tumor levels; p<0.001). In addition, a high MAGE-D4 expression was more frequently seen in squamous cell carcinoma than in adenocarcinoma (p=0.008), and less frequently in well-differentiated tumors than in moderately to poorly differentiated tumors (p=0.036). There was no difference in the postoperative survival between low and high MAGE-D4 patients (5-year survival rates, 65% and 69%, respectively; p=0.742).


CONCLUSIONS
MAGE-D4 plays some roles in tumor cells proliferation in NSCLC, but MAGE-D4 expression status did not provided a prognostic significance.
Ito
Shinya
S
Department of Thoracic Surgery, Graduate School of Medicine, Kyoto University, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan.
Kawano
Yozo
Y
Katakura
Hiromichi
H
Takenaka
Kazumasa
K
Adachi
Masashi
M
Sasaki
Manabu
M
Shimizu
Keiji
K
Ikenaka
Kazuhiro
K
Wada
Hiromi
H
Tanaka
Fumihiro
F
D000818:Animals; D000951:Antigens, Neoplasm; D017209:Apoptosis; D002289:Carcinoma, Non-Small-Cell Lung / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015151:Immunoblotting; D007424:Intracellular Fluid / Q000378:metabolism; D008175:Lung Neoplasms / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D009363:Neoplasm Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics*
D000951:Antigens, Neoplasm; C120897:MAGED1 protein, human; D009363:Neoplasm Proteins; D012333:RNA, Messenger