Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0154059 (Esophagus)
 2,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cyclooxygenase-2 (COX-2) expression is increased in metaplastic and dysplastic Barrett's esophageal epithelium and it is thought that selective COX-2 inhibitors could offer hope as chemoprevention therapy. The aim of the study was to investigate the in vivo effect of celecoxib on COX-2 expression in patients with Barrett's esophagus and no recent history of non-steroidal anti-inflammatory drug use. Endoscopic mucosal biopsy specimens were collected at baseline and after 28 days of therapy in a patient treated with celecoxib 200 mg twice daily. Samples were analyzed for COX-2 expression by immunoblot analysis with chemiluminescence detection. COX-2 expression was found to decline 20% and 44% at two different biopsy sites compared to the baseline sample. Longer exposures revealed a number of previously unidentified proteins above and below the 67 kDa COX-2 protein including 38 kDa and 45 kDa proteins which were present only at study completion consistent with up-regulation after celecoxib therapy. Further investigations of the 38 kDa and 45 kDa proteins were undertaken using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) with immunoblot and MALDI-TOF (matrix assisted laser desorption ionization - time of flight) analysis but no matches were found and results were inconclusive. Unmatched masses from MALDI-TOF peptide mass fingerprinting were compared with human COX-2 (67 kDa) and COX-2b (39 kDa) using unspecific cleavage. Peptide sequence homology with COX-2 and COX-2b was found for a length of 19 amino acids. Based on immunodetection, molecular weight and equivical MALDI-TOF results, one of these up-regulated proteins may be COX-2b.
Dis Esophagus 2007
PMID:Effect of celecoxib on cyclooxygenase-2 expression and possible variants in a patient with Barrett's esophagus. 1750 25

To investigate cyclooxygenase-2 (COX-2) mRNA expression in human esophageal squamous cell carcinoma and the effect of a non-steroidal anti-inflammatory drug (NSAID) on it, in order to explore the mechanism of COX-2 in esophageal squamous cell carcinoma (ESCC) carcinogenesis and the ability of NSAID to prevent or treat ESCC. Frozen specimens of human ESCC and adjacent normal esophageal squamous epithelium pairs (n = 22) were examined for COX-2 mRNA expression by reverse-transcription polymerase chain reaction (RT-PCR). After incubation with aspirin (a non-selective COX inhibitor) or Nimesulide (a selective COX-2 inhibitor), the proliferation status of two human esophageal squamous cancer cell lines, EC-9706 and EC-109, was quantified by 3-(4,5-dimethyl-thiazol-2yl)-2,5-diphenyltetrazolium bromide assay. The expression of COX-2 mRNA in these cells was detected by RT-PCR. COX-2 mRNA was expressed in 12 of 22 (54.5%) ESCC tissue samples, but it was undetectable in all the specimens of adjacent normal esophageal squamous epithelium COX-2 mRNA expression. Both aspirin (5-20 mmol/L) and Nimesulide (0.1-0.8 mmol/L) inhibited EC-9706 cell line proliferation and suppressed its COX-2 mRNA expression dose-dependently. However, only aspirin (5-20 mmol/L) could inhibit proliferation in the EC-109 cell line and suppress COX-2 mRNA expression. Nimesulide (0.1-0.8 mmol/L) could neither inhibit EC-109 cell growth nor suppress COX-2 mRNA expression. COX-2 mRNA expression is a frequent phenomenon in human ESCC tissue samples and plays an important role in the carcinogenesis of ESCC. NSAID may be useful in the chemoprevention and therapy of human ESCC and its effects are likely to be mediated by modulating COX-2 activity.
Dis Esophagus 2008
PMID:COX-2 mRNA expression in esophageal squamous cell carcinoma (ESCC) and effect by NSAID. 1819 33