Neogenin expression may be inversely correlated to the tumorigenicity of human breast cancer.
BACKGROUND
Neogenin is expressed in cap cells that have been suggested to be mammary stem or precursor cells. Neogenin is known to play an important role in mammary morphogenesis; however its relationship to tumorigenesis remains to be elucidated.


METHODS
To compare the expression levels of neogenin in cells with different tumorigenicity, the expression levels in M13SV1, M13SV1R2 and M13SV1R2N1 cells, which are immortalized derivatives of type I human breast epithelial cells, were evaluated. Then we measured the expression level of neogenin in paired normal and cancer tissues from eight breast cancer patients. Tissue array analysis was performed for 54 human breast tissue samples with different histology, and the results were divided into four categories (none, weak, moderate, strong) by a single well-trained blinded pathologist and statistically analyzed.


RESULTS
The nontumorigenic M13SV1 cells and normal tissues showed stronger expression of neogenin than the M13SV1R2N1 cells and the paired cancer tissues. In the tissue array, all (8/8) of the normal breast tissues showed strong neogenin expression, while 93.5% (43/46) of breast cancer tissues had either no expression or only moderate levels of neogenin expression. There was a significant difference, in the expression level of neogenin, in comparisons between normal and infiltrating ductal carcinoma (p < 0.001).


CONCLUSIONS
Neogenin may play a role in mammary carcinogenesis as well as morphogenesis, and the expression may be inversely correlated with mammary carcinogenicity. The value of neogenin as a potential prognostic factor needs further evaluation.
Lee
Jeong Eon
JE
Department of Surgery, Seoul National University College of Medicine, 28 Yongon-dong, Seoul 110-744, Korea. paojlus@hanmail.net
Kim
Hee Joung
HJ
Bae
Ji Yeon
JY
Kim
Seok Won
SW
Park
Joon-Suk
JS
Shin
Hyuk Jai
HJ
Han
Wonshik
W
Kim
Sung-Won
SW
Kang
Kyung-Sun
KS
Noh
Dong-Young
DY
D014408:Biomarkers, Tumor / Q000096:biosynthesis; D015153:Blotting, Western; D001940:Breast / Q000378:metabolism* / Q000473:pathology; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D002460:Cell Line; D045744:Cell Line, Tumor; D004847:Epithelial Cells / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000096:biosynthesis*; D015233:Models, Statistical; D009362:Neoplasm Metastasis; D011379:Prognosis; D014018:Tissue Distribution
D014408:Biomarkers, Tumor; D008565:Membrane Proteins; C091279:neogenin