Characterization of a putative ovarian oncogene, elongation factor 1alpha, isolated by panning a synthetic phage display single-chain variable fragment library with cultured human ovarian cancer cells.
OBJECTIVE
In an effort to identify cell surface targets and single short-chain antibody (scFv) for ovarian cancer therapy, we used a phage display approach to isolate an antibody with high reactivity against ovarian cancer.


METHODS
A phage scFv library was subjected to panning against human SK-OV-3 ovarian cancer cells. A clone with high reactivity was selected and tested in immunoperoxidase staining on a panel of normal tissues and ovarian carcinoma. Using immunoprecipitation, a differentially expressed band was analyzed by mass spectrometry. The antigen subclass was characterized with reverse transcription-PCR on cDNA library of normal tissues, and 91 ovarian cancer specimens, and correlated with clinicohistopathologic characteristics.


RESULTS
Ninety-six individual scFv clones were screened in ELISA following panning. scFv F7 revealed high reactivity with ovarian cancer cell lines and showed intense staining of 15 fresh ovarian cancer specimens and no staining of a panel of normal tissues. A 40-kDa protein was identified to be translation elongation factor 1alpha1 (EEF1A1; P < 0.05). The expression of EEF1A2, a highly homologous and functionally similar oncogene, was found to be restricted only to the normal tissues of the heart, brain, and skeletal muscle. Aberrant EEF1A2 mRNA expression was found in 21 of 91 (23%) of ovarian cancer specimens and significantly correlated with increased likelihood of recurrence (P = 0.021).


CONCLUSIONS
scFv F7 may represent an ovarian cancer-specific antibody against translation EEF1A family of translational factors. We propose that EEF1A2 may be a useful target for therapy of human ovarian cancer.
Sharma
Sameer
S
Department of Gynecologic Oncology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
Tammela
Jonathan
J
Wang
Xinhui
X
Arnouk
Hilal
H
Driscoll
Deborah
D
Mhawech-Fauceglia
Paulette
P
Lele
Shashikant
S
Kazim
A Latif
AL
Odunsi
Kunle
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000378:metabolism; D045744:Cell Line, Tumor; D005260:Female; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics / Q000276:immunology*; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000378:metabolism*; D010053:Ovary / Q000473:pathology; D020648:Peptide Elongation Factor 1 / Q000235:genetics* / Q000502:physiology*; D019151:Peptide Library; D014176:Protein Biosynthesis; D014018:Tissue Distribution
D007135:Immunoglobulin Variable Region; D020648:Peptide Elongation Factor 1; D019151:Peptide Library