Cyclooxygenase-2 is expressed in human fibroblasts isolated from intraperitoneal adhesions but not from normal peritoneal tissues

Abstract

Objective To determine whether the COX-2 gene is expressed in human fibroblasts isolated from normal peritoneal and adhesion tissues. Design Prospective experimental study. Setting University medical center. Patient(s) Five patients undergoing laparotomy for pelvic pain. Primary cultures of fibroblasts were taken from both peritoneum and adhesion tissues. Intervention(s) Hypoxia treatment of the primary cultured fibroblasts. Main outcome measure(s) We used the multiplex reverse transcription–polymerase chain reaction (RT-PCR) and immunohistochemistry techniques to determine whether COX-2 mRNA and its protein were present in normal peritoneal and adhesion fibroblasts from the same patients. Total RNA was extracted from cultured fibroblasts and subjected to multiplex RT-PCR to detect the presence of COX-2 mRNA in these cells. Cultured fibroblasts from all tissues were also fixed on slides and stained with COX-2 monoclonal antibody labeled with immunofluorescence. Result(s) COX-2 mRNA and its protein were absent in normal peritoneal fibroblasts from all five subjects but were present in adhesion fibroblasts from the same patients, as indicated by the multiplex RT-PCR and immunohistochemistry techniques. Hypoxia treatment significantly induced the mRNA and COX-2 protein levels in normal peritoneal fibroblasts to levels seen in adhesion fibroblasts under normoxic conditions. However, hypoxia had no effects on COX-2 expression by adhesion fibroblasts. Conclusion(s) Adhesion fibroblasts develop a specific phenotype, an adhesion phenotype, which is in part characterized by the expression of COX-2. The expression of COX-2 mRNA in adhesion fibroblasts and the induction of COX-2 in peritoneal fibroblasts in response to hypoxia indicate a possible inflammatory response. Regulation of COX-2 may alter peritoneal healing and may provide the opportunity to reduce postoperative adhesion development.