Estrogen-responsive finger protein as a new potential biomarker for breast cancer.
OBJECTIVE
Estrogen-responsive finger protein (Efp) is a member of RING finger-B box-Coiled Coil family and is also a downstream target of estrogen receptor alpha. Previously, Efp was shown to mediate estrogen-induced cell growth, which suggests possible involvement in the development of human breast carcinomas. In this study, we examined expression of Efp in breast carcinoma tissues and correlated these findings with various clinicopathologic variables.


METHODS
Thirty frozen specimens of breast carcinomas were used for immunohistochemistry and laser capture microdissection/real-time PCR of Efp. Immunohistochemistry for Efp was also done in 151 breast carcinoma specimens fixed with formalin and embedded in paraffin wax.


RESULTS
Efp immunoreactivity was detected in breast carcinoma cells and was significantly associated with the mRNA level (n = 30). Efp immunoreactivity was positively associated with lymph node status or estrogen receptor alpha status and negatively correlated with histologic grade or 14-3-3sigma immunoreactivity (n = 151). Moreover, Efp immunoreactivity was significantly correlated with poor prognosis of breast cancer patients, and multivariate analyses of disease-free survival and overall survival for 151 breast cancer patients showed that Efp immunoreactivity was the independent marker.


CONCLUSIONS
Our data suggest that Efp immunoreactivity is a significant prognostic factor in breast cancer patients. These findings may account for an oncogenic role of Efp in the tumor progression of breast carcinoma.
Suzuki
Takashi
T
Department of Pathology, Tohoku University School of Medicine, Aoba-ku, Sendai, Miyagi-ken, Japan. t-suzuki@patholo2.med.tohoku.ac.jp
Urano
Tomohiko
T
Tsukui
Tohru
T
Horie-Inoue
Kuniko
K
Moriya
Takuya
T
Ishida
Takanori
T
Muramatsu
Masami
M
Ouchi
Yasuyoshi
Y
Sasano
Hironobu
H
Inoue
Satoshi
S
D048948:14-3-3 Proteins / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D000070584:Tripartite Motif Proteins; D044767:Ubiquitin-Protein Ligases
D048948:14-3-3 Proteins; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D014157:Transcription Factors; D000070584:Tripartite Motif Proteins; C084523:TRIM25 protein, human; D044767:Ubiquitin-Protein Ligases