Osteopontin expression in squamous cell cancer of the esophagus.
BACKGROUND
The purpose of this study was to better understand the role of osteopontin (OPN) in esophageal squamous cell carcinoma (ESCC) by comparing the OPN mRNA level in ESCC tumor tissue and matched normal tissue and by determining the prognostic significance of the gene expression.


METHODS
Initially, by an oligo-nucleotide microarray hybridization technique, OPN expressions were found to consistently elevate at least twofold in three ESCC tissues compared with their adjacent normal ones. Subsequently, the expression of OPN mRNA was detected by real-time QRT-PCR among the 58 fresh surgical ESCC specimens. The clinical information was obtained by chart review.


RESULTS
OPN mRNA expression was detectable in 58 of 58 (100%) tumor specimens and 57 of 58 (98.3%) nonmalignant esophageal specimens. OPN expression was higher in tumor tissue than in the matched normal tissue in 54 of 58 (93.1%) individual cases. The overall median mRNA expression level of OPN was approximately 8.8-fold higher in tumor tissues (4.1; range: 0.02-247) compared with matched normal esophageal tissues (0.5; range, 0.0-21.4; p < 0.001). Overexpression of OPN mRNA was significantly associated with clinical stage (p = 0.01). The more severe the clinical stage (from I-II, III, to IV) was the higher frequency of overexpression of OPN mRNA. No significant associations were found between overexpression of OPN mRNA and the patients' survival (p = 0.27).


CONCLUSIONS
Our findings suggest OPN is associated with esophageal tumorigenesis and progression, but not patients' survival.
Wu
I-Chen
IC
Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, No. 100 Tz-You 1st road, Kaohsiung, Taiwan.
Wu
Ming-Tsang
MT
Chou
Shah-Hwa
SH
Yang
Sheau-Fang
SF
Goan
Yih-Gang
YG
Lee
Jang-Ming
JM
Chou
Yi-Pin
YP
Bair
Ming-Jong
MJ
Wang
Tsang-En
TE
Chen
Angela
A
Chang
Wen-Hsiung
WH
Kuo
Fu-Chen
FC
Wu
Deng-Chyang
DC
D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016009:Chi-Square Distribution; D018450:Disease Progression; D004938:Esophageal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D004947:Esophagus / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D053495:Osteopontin / Q000235:genetics* / Q000378:metabolism; D011379:Prognosis; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate
D014408:Biomarkers, Tumor; D053495:Osteopontin