Aberrant expression of ether à go-go potassium channel in colorectal cancer patients and cell lines.
OBJECTIVE
To study the expression of ether à go-go (Eag1) potassium channel in colorectal cancer and the relation-ship between their expression and clinico-pathological features.


METHODS
The expression levels of Eag1 protein were determined in 76 cancer tissues with paired non-cancerous matched tissues as well as 9 colorectal adenoma tissues by immunohistochemistry. Eag1 mRNA expression was detected in 13 colorectal cancer tissues with paired non-cancerous matched tissues and 4 colorectal adenoma tissues as well as two colorectal cancer cell lines (LoVo and HT-29) by reverse transcription PCR.


RESULTS
The frequency of positive expression of Eag1 protein was 76.3% (58/76) and Eag1 mRNA was 76.9% (10/13) in colorectal cancer tissue. Expression level of Eag1 protein was dependent on the tumor size, lymphatic node metastasis, other organ metastases and Dukes' stage (P < 0.05), while not dependent on age, sex, site and degree of differentiation. Eag1 protein and mRNA were negative in normal colorectal tissue, and absolutely negative in colorectal adenomas except that one case was positively stained for Eag1 protein.


CONCLUSIONS
Eag1 protein and mRNA are aberrantly expressed in colorectal cancer and occasionally expressed in colorectal adenoma. The high frequency of expression of Eag1 in tumors and the restriction of normal expression to the brain suggest the potential of this protein for diagnostic, prognostic and therapeutic purposes.
Ding
Xiang-Wu
XW
Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China.
Yan
Juan-Juan
JJ
An
Ping
P
Lü
Peng
P
Luo
He-Sheng
HS
D000236:Adenoma / Q000378:metabolism* / Q000473:pathology; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology; D051638:Ether-A-Go-Go Potassium Channels / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D019073:HT29 Cells; D006801:Humans; D008297:Male; D008875:Middle Aged; D012007:Rectum / Q000473:pathology
D051638:Ether-A-Go-Go Potassium Channels; C496884:KCNH1 protein, human