Expression pattern of the novel gene EG-1 in cancer.
OBJECTIVE
We recently discovered a novel gene responsive to tumor-conditioned media: endothelial-derived gene 1 (EG-1). Its transcript has been shown to be present in epithelial cells, as well as in endothelial cells. In this study, we examined the levels of EG-1 protein expression in breast, colon, prostate, and lung cancers, which constitute the four most common solid malignancies in the United States.


METHODS
Polyclonal antibodies were generated that recognize the EG-1 peptide. These antibodies were used in immunoblot analysis, as well as immunohistochemistry of multiple human clinical specimens of cancer.


RESULTS
In immunoblots of whole cell lysates, EG-1 antibodies revealed the presence of a 22-kDa peptide. Immunohistochemistry of breast, colon, and prostate specimens showed higher levels of EG-1 peptides in cancer tissues, in comparison with their benign counterparts. However, EG-1 expression was minimal in both benign and malignant lung tissues.


CONCLUSIONS
Here, we demonstrated that the expression of EG-1 is elevated in cancerous in comparison to benign epithelial cells, as seen in immunohistochemistry of human pathological specimens. These observations collectively support the hypothesis that the novel gene EG-1 is associated with the malignant phenotype of the common epithelial-derived cancers of the breast, colon, and prostate.
Zhang
Liping
L
Department of Surgery, Division of Oncology, University of California at Los Angeles, Los Angeles, California 90095, USA.
Maul
Raymond Scott
RS
Rao
JianYu
J
Apple
Sophia
S
Seligson
David
D
Sartippour
Maryam
M
Rubio
Rosalio
R
Brooks
Mai N
MN
D000906:Antibodies / Q000737:chemistry; D015153:Blotting, Western; D002460:Cell Line; D045744:Cell Line, Tumor; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D056892:Mediator Complex; D018613:Microscopy, Confocal; D009369:Neoplasms / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry; D010641:Phenotype; D011506:Proteins / Q000378:metabolism*; D014162:Transfection
D000906:Antibodies; C496877:MED28 protein, human; D056892:Mediator Complex; D010455:Peptides; D011506:Proteins