[Expression and clinical significance of Mucin and E-cadherin in colorectal tumors].
OBJECTIVE
Mucin (MUC), a glycoprotein with high molecular weight, can lubricate and protect the epithelium. E-cadherin (E-cad) is helpful in keeping the polarity and integrity of the epithelium. The abnormal expression of Mucin and E-cad is involved in the genesis of many tumors. This study was to investigate the expression of MUC1, MUC2, MUC5AC and E-cad in different colorectal tumor tissues, and explore their correlations to clinicopathologic features of colorectal cancer and the correlations of MUC1, MUC2, and MUC5AC expression to E-cad expression.


METHODS
The expression of MUC1, MUC2, MUC5AC and E-cad in 150 specimens of normal colorectal mucosa, 150 specimens of colorectal adenoma and 150 specimens of colorectal adenocarcinoma was detected by immunohistochemistry. Patients' survival was analyzed by Kaplan-Meier method. The correlations of MUC1, MUC2, and MUC5AC expression to E-cad expression were analyzed by spearman's rank correlation.


RESULTS
The positive rates of MUC1 were 0.07% in normal colorectal mucosa, 12.7% in colorectal adenoma, and 45.3% in colorectal adenocarcinoma. Those of MUC2 were 100%, 90.0% and 52.6%, respectively. Those of MUC5AC were 8.7%, 30.7% and 44.0%, respectively. Those of E-cad were 98.7%, 82.0% and 54.0%, respectively. In colorectal adenocarcinoma, the expression of MUC1 and MUC2 was correlated to tumor differentiation, invasion, lymph node metastasis and Dukes' stage (P<0.05); the expression of MUC5AC was correlated to tumor differentiation and invasion (P<0.01); the expression of E-cad was correlated to tumor differentiation (P<0.01). The 5-year survival rate was significantly higher in MUC1-negative group, MUC2-positive group and E-cadherin-positive group than in their counterparts (P<0.05). In colorectal adenocarcinoma, MUC1 expression was negatively correlated to E-cad expression (r=-0.234, P=0.004), MUC2 and MUC5AC expression were positively correlated to E-cad expression (r=0.170, P=0.038; r=0.198, P=0.015).


CONCLUSIONS
In colorectal adenocarcinoma, MUC expression is obviously correlated to E-cad expression. The up-regulation of MUC1 and MUC5AC expression and the down-regulation of MUC2 and E-cad expression may be involved in the genesis of colorectal tumors and reflect the prognosis to a certain extent.
Yu
Xiu-Wen
XW
Department of Pathology, Qiqihaer Medical College, Qiqihaer, Heilongjiang, 161042, PR China. yxw05@sohu.com
Rong
Wei
W
Xu
Feng-Lin
FL
Xu
Guang-You
GY
Sun
Yu-Rong
YR
Feng
Mei-Yan
MY
D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000236:Adenoma / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D015820:Cadherins / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D055271:Mucin 5AC / Q000378:metabolism; D018396:Mucin-1 / Q000378:metabolism; D055262:Mucin-2 / Q000378:metabolism; D009077:Mucins / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000378:metabolism* / Q000473:pathology; D015996:Survival Rate; D055815:Young Adult
D015820:Cadherins; D055271:Mucin 5AC; D018396:Mucin-1; D055262:Mucin-2; D009077:Mucins