Translation elongation factor eEF1A2 is a potential oncoprotein that is overexpressed in two-thirds of breast tumours.
BACKGROUND
The tissue-specific translation elongation factor eEF1A2 was recently shown to be a potential oncogene that is overexpressed in ovarian cancer. Although there is no direct evidence for an involvement of eEF1A2 in breast cancer, the genomic region to which EEF1A2 maps, 20q13, is frequently amplified in breast tumours. We therefore sought to establish whether eEF1A2 expression might be upregulated in breast cancer.


METHODS
eEF1A2 is highly similar (98%) to the near-ubiquitously expressed eEF1A1 (formerly known as EF1-alpha) making analysis with commercial antibodies difficult. We have developed specific anti-eEF1A2 antibodies and used them in immunohistochemical analyses of tumour samples. We report the novel finding that although eEF1A2 is barely detectable in normal breast it is moderately to strongly expressed in two-thirds of breast tumours. This overexpression is strongly associated with estrogen receptor positivity.


CONCLUSIONS
eEF1A2 should be considered as a putative oncogene in breast cancer that may be a useful diagnostic marker and therapeutic target for a high proportion of breast tumours. The oncogenicity of eEF1A2 may be related to its role in protein synthesis or to its potential non-canonical functions in cytoskeletal remodelling or apoptosis.
Tomlinson
Victoria A L
VA
Molecular Medicine Centre, Western General Hospital, School of Molecular and Clinical Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK. V.A.L.Tomlinson@sms.ed.ac.uk
Newbery
Helen J
HJ
Wray
Naomi R
NR
Jackson
Juliette
J
Larionov
Alexey
A
Miller
William R
WR
Dixon
J Michael
JM
Abbott
Catherine M
CM
D017209:Apoptosis; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D015233:Models, Statistical; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism*; D020648:Peptide Elongation Factor 1 / Q000096:biosynthesis* / Q000378:metabolism; D012313:RNA / Q000737:chemistry; D011960:Receptors, Estrogen / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation
C503234:EEF1A2 protein, human; D020648:Peptide Elongation Factor 1; D011960:Receptors, Estrogen; D012313:RNA