Involvement of EphA2 in head and neck squamous cell carcinoma: mRNA expression, loss of heterozygosity and immunohistochemical studies.
EphA2 is a 130-kDa transmembrane protein primarily found in adult human epithelial cells and is a member of one of the largest receptor tyrosine kinases. It is located on 1p36.1, a genetic hot spot in cancer. EphA2 overexpression has been observed in aggressive solid tumors and its potential role in tumorigenesis, which includes cell growth, survival, migration and angiogenesis have been reported. However, the role of EphA2 remains unknown in head and neck cancer. In this study, we investigated the genetic profile of EphA2 in primary head and neck squamous cell carcinoma (HNSCC) by determining mRNA level, status of loss of heterozygosity and protein expression. mRNA expression was also correlated with clinicopathological data. Infrequent loss of heterozygosity (20%) was observed, though a 10-fold increase of mRNA expression in tumors compared to normal tissues was noted. A significant number of samples with normal to high mRNA expression was observed among patients with regional metastasis, with T3-T4 tumor size and with moderate to poor differentiation. However, statistical studies did not show any correlation between mRNA expression and any of the clinicopathological parameters. Tumor cells expressed EphA2 protein, but only weakly. These results suggest that EphA2 might be involved in the early development of HNSCC although not directly responsible for its progression.
Rivera
Rosario S
RS
Department of Oral Pathology and Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama City 700-8528, Japan.
Gunduz
Mehmet
M
Nagatsuka
Hitoshi
H
Gunduz
Esra
E
Cengiz
Beyhan
B
Fukushima
Kunihiro
K
Beder
Levent Bekir
LB
Pehlivan
Davut
D
Yamanaka
Noboru
N
Shimizu
Kenji
K
Nagai
Noriyuki
N
D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006258:Head and Neck Neoplasms / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D019656:Loss of Heterozygosity; D008297:Male; D008875:Middle Aged; D008957:Models, Genetic; D009362:Neoplasm Metastasis; D012333:RNA, Messenger / Q000378:metabolism*; D036104:Receptor, EphA2 / Q000096:biosynthesis* / Q000235:genetics*
D008024:Ligands; D012333:RNA, Messenger; D036104:Receptor, EphA2