Augmented expression of endothelin-1, endothelin-3 and the endothelin-B receptor in breast carcinoma.
OBJECTIVE
Endothelins (ETs) are peptides expressed in many tumours which may stimulate angiogenesis and desmoplasia. Because ETs have not been extensively studied mammary neoplasia, we assessed ET protein and mRNA expression and receptor mRNA expression in normal and neoplastic breast tissues.


RESULTS
Tissues from five normal breasts, six fibroadenomas, seven ductal carcinomas in situ (DCIS) and 25 invasive carcinomas were stained with anti-ET-1 and anti-ET-3 antibodies and analysed using a grading system. ET-1, ET-3, ETA and ETB mRNA expression was assessed by quantitative RT-PCR from eight carcinomas and five normals. Weak staining for ET-1 and ET-3 was detected in all normals. Moderate to strong staining was seen in 72% and 64% of carcinomas for ET-1 and ET-3, respectively. Most fibroadenomas showed weak positivity for ET-1 (83%) and ET-3 (67%). ET-1 and ET-3 mRNA levels were upregulated in carcinomas compared with normal breast. No ETA mRNA was not detected in any tissue. ETB mRNA was detected in normal breast and was increased in carcinomas.


CONCLUSIONS
These results suggest that the ET system is altered in breast carcinomas and this may be of importance in the progression from in-situ to invasive carcinoma.
Alanen
K
K
Departments of; Pathology and Microbiology; Immunology, The University of Western Ontario, London Ontario, Canada.
Deng
D X
DX
Chakrabarti
S
S
D015139:Blotting, Southern; D001940:Breast / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D002278:Carcinoma in Situ / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D019332:Endothelin-1 / Q000032:analysis / Q000235:genetics*; D019334:Endothelin-3 / Q000032:analysis / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin / Q000032:analysis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D019332:Endothelin-1; D019334:Endothelin-3; D012333:RNA, Messenger; D044023:Receptor, Endothelin B; D017466:Receptors, Endothelin