Prognostic significance of EpCAM expression in human esophageal cancer.
EpCAM is a 40-kDa epithelial transmembrane glycoprotein that has a well-known role in Ca2+ -independent homophilic cell-cell adhesion. Recently, correlations between EpCAM expression and clinicopathological features have been investigated in various cancers. We examined EpCAM expression in surgical specimens from esophageal cancer patients (n = 138), using real-time RT-PCR, immunohistochemistry and ELISA. The mean expression level of EpCAM mRNA in tumor tissues was significantly higher than that in corresponding normal tissues (P < 0.0001). Immunohistochemically, positive staining for EpCAM was found in 135 (97.8%) of the 138 primary tumor specimens. EpCAM expression was correlated with tumor depth (P = 0.0005), stage (P = 0.0037), blood-vessel invasion (P = 0.0397) and infiltrative growth pattern (P = 0.0015). The survival rates of patients with tumors with high EpCAM expression was significantly higher than those for patients with tumors with low EpCAM expression (P = 0.0213). Furthermore, the serum EpCAM levels of patients with esophageal cancer were significantly higher than those of normal volunteers (P = 0.0221). The survival rates of patients with a high EpCAM level in the peripheral vein were also significantly higher than those for patients with a low serum EpCAM level (P = 0.0291). The serum EpCAM level in the peripheral vein was independently associated with prognosis (P = 0.0074; hazard ratio 7.40). Tumor-specific EpCAM expression and release into the circulation may serve as effective immunotherapy in esophageal cancer patients.
Kimura
Hitoshi
H
Department of General Surgical Science, Gunma University, Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan. hkimura@med.gunma-u.ac.jp.
Kato
Hiroyuki
H
Faried
Ahmad
A
Sohda
Makoto
M
Nakajima
Masanobu
M
Fukai
Yasuyuki
Y
Miyazaki
Tatsuya
T
Masuda
Norihiro
N
Fukuchi
Minoru
M
Kuwano
Hiroyuki
H
D000368:Aged; D000951:Antigens, Neoplasm / Q000235:genetics*; D001483:Base Sequence; D015815:Cell Adhesion Molecules / Q000235:genetics*; D017931:DNA Primers; D000071858:Epithelial Cell Adhesion Molecule; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D013997:Time Factors
D000951:Antigens, Neoplasm; D015815:Cell Adhesion Molecules; D017931:DNA Primers; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule