Association of enhanced cyclooxygenase-2 expression with possible local immunosuppression in human colorectal carcinomas.
Ann Surg Oncol
; 8(5): 458-65, 2001 Jun.
Article
en En
| MEDLINE
| ID: mdl-11407522
ABSTRACT
BACKGROUND:
Prostaglandin (PG) E2 has an influence on antitumor lymphocyte reactions and causes local immunosuppression at tumor sites. The contribution of cyclooxygenase (COX), a key enzyme in PGE2 synthesis, to this effect is still unclear. We examined if cyclooxygenase (COX)-2 is involved in local immunosuppression in human colon carcinoma cell lines and in clinical tumor specimens.METHODS:
PGE2 concentrations were measured in culture media from a highly COX-2-expressing human colon carcinoma cell line (CE-1) and other cell lines. Lymphocyte proliferation in response to a mitogen was used to evaluate immunosuppression in tumor cell-lymphocyte cocultures with and without selective COX-2 inhibitor NS-398. We also evaluated expression of COX-2 mRNA in surgical specimens of colorectal carcinoma by reverse transcription polymerase chain reaction (RT-PCR) and COX-2 protein by immunohistochemistry, correlating COX-2 expression with clinicopathologic features.RESULTS:
CE-1 cells produced large amounts of PGE2, which was significantly inhibited by NS-398. The proliferation index of lymphocytes cocultured with CE-1 cells was significantly less than that of control lymphocytes; again, this effect was inhibited by NS-398. While human colorectal carcinoma tissue expressed more COX-2 mRNA and protein than nonneoplastic tissue, no significant correlation was found between COX-2 levels and clinicopathologic features.CONCLUSIONS:
Overexpression of COX-2 in colon cancer may cause local immunosuppression, and COX-2 inhibitors might be therapeutically useful against these tumors.
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Base de datos:
MEDLINE
Asunto principal:
Neoplasias Colorrectales
/
Adenocarcinoma
/
Terapia de Inmunosupresión
/
Prostaglandina-Endoperóxido Sintasas
/
Isoenzimas
Tipo de estudio:
Risk_factors_studies
Límite:
Adult
/
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Ann Surg Oncol
Asunto de la revista:
NEOPLASIAS
Año:
2001
Tipo del documento:
Article
País de afiliación:
Japón