Localisation of COX-2 protein is different in breast ductal carcinoma and adjacent non-tumour ductal epithelium.

Abstract

INTRODUCTION:

A number of findings suggest that cyclooxygenase-2 (COX-2) is overexpressed in breast tumours. However, there is a lack of consensus in the literature regarding the pattern of expression of this protein in invasive breast ductal carcinoma and in the adjacent non-tumour ductal epithelium. This study compares the expression of COX-2 mRNA and protein in breast ductal carcinoma relative to non-tumour breast tissue.

MATERIAL AND METHODS:

We analysed the expression of COX-2 mRNA by quantitative PCR, and COX-2 protein by immunohistochemistry in invasive ductal carcinoma as well as in non-tumour adjacent ductal epithelium from 34 breast biopsies diagnosed as being invasive ductal carcinoma. As control, we analysed expression of COX-2 protein by immunohistochemistry in surgically-resected benign breast lesions.

RESULTS:

Our results show that COX-2 mRNA and protein are overexpressed in non-tumour ductal epithelium compared with invasive ductal carcinoma. However, the pattern of the protein expression is different in tumour and non-tumour tissue: COX-2 protein is expressed predominantly in the membrane of the non-tumour ductal epithelium (including in benign breast lesions) while, in invasive ductal carcinoma cells, it is localised in the cytoplasm.

CONCLUSIONS:

The non-tumour ductal epithelium adjacent to invasive ductal carcinoma shows a higher COX-2 expression than does the invasive ductal carcinoma. However, the different localisation of the immunohistochemically-detected protein suggests a possible post-translational regulation of the protein.

• Authors: P Cejas, M A García-Cabezas, E Casado, J Barriuso, J A Fresno, E Díaz, C Belda-Iniesta, J Castro, E Espinosa, P Zamora, J Feliu, A Redondo, D A Hardisson, M González-Barón
• Journal: Clinical & translational oncology : official publication of the Federation of Spanish Oncology Societies and of the National Cancer Institute of Mexico (Clin Transl Oncol) Vol. 7 Issue 6 Pg. 239-43 (Jul 2005) ISSN: 1699-048X [Print] Italy
• PMID: 16131446 (Publication Type: Journal Article)

Chemical References

• RNA, Messenger

Topics

• Adult
• Aged
• Breast (metabolism, pathology)
• Breast Neoplasms (metabolism, pathology)
• Carcinoma, Ductal, Breast (metabolism, pathology)
• Epithelium (metabolism, pathology)
• Female
• Humans
• Immunohistochemistry
• Middle Aged
• Polymerase Chain Reaction
• RNA, Messenger (analysis)