Expression of estrogen sulfotransferase in breast tissues and the regulation of ESTmRNA by estrogen
Deng, W.-h.; Wu, Y.-y.; Luo, L.-h.; Wang, S.; Tang, W.-q.; Zhang, Y.-f.
Zhonghua Yi Xue Za Zhi 83(21): 1891-1894
2003
ISSN/ISBN: 0376-2491 PMID: 14642074 Document Number: 559486
To detect the expression of estrogen sulfotransferase (EST) in breast tissues, and to investigate its significance in breast carcinogenesis and the relationship between EST mRNA and estrogen. Seven specimens of normal human breast tissues from patients with benign breast diseases were implanted subcutaneously into athymic nude mice, one specimen divided into many pieces to be implanted into 2 groups of mice, totalling 14 mice. Then the 14 mice were divided into 2 groups: as control and the other injected intramuscularly with estradiol benzoate (B-E(2)) every other day for 6 weeks. Six weeks after, the implanted tissues were taken out. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of EST mRNA in 24 specimens of breast cancer, 6 specimens of normal breast tissues around the breast fibroadenoma, all resected during operation, and the specimens of implanted normal breast tissues from the mice (control group and B-E(2) group). The protein expression of estrogen receptor (ER) was detected by immunohistochemistry in the 24 specimens of breast cancer. EST mRNA was expressed in all normal human breast tissues and the expression was increased in the grafts from mice of B-E(2) group. However, the specimens of breast cancer showed decrease or absence of EST mRNA expression. EST mRNA expression is decreased or lost in breast cancer tissues. EST mRNA can be regulated by estrogen in normal breast tissues.