Cyclooxygenase-2 expression in the endometrium at the end of 2 years' continuous combined hormone replacement therapy.
OBJECTIVE
To evaluate the change of endometrial histology and the expression of cyclooxygenase-2 (Cox-2) in the endometrium after continuous combined hormone replacement therapy (HRT).


METHODS
Forty-five postmenopausal women were recruited. All participants received 0.625 mg conjugated equine estrogen (CEE) and 2.5 mg medroxyprogesterone (MPA) daily for 2 years. Endometrial biopsy was performed twice, before medication (baseline) and after 2 years of HRT, respectively. Immunohistochemistry was used to detect the presence of Cox-2 expression.


RESULTS
More atrophic and weak secretory features of endometrium were noted after the 2-year HRT. Endometrial hyperplasia and carcinoma were not found and immunohistochemistry results revealed that Cox-2 was not expressed in the endometrium.


CONCLUSIONS
Cox-2, known to play an important role in the tumorigenesis of cancer, was not stained in endometrium tissue after hormonal induction and more endometrium atrophy was noted after the 2-year HRT. From the results, it is noted that continuous combined HRT may be a relatively safe and appropriate regimen for long-term use in postmenopausal women.
Hsu
Shih-Cheng
SC
Department of Obstetrics and Gynecology, Kaohsiung Municipal Hsiao Kang Hospital, Hsiao-Kang District, 812 Kaohsiung, Taiwan, ROC.
Long
Cheng-Yu
CY
Yang
Cheng-Hui
CH
Wu
Ching-Hu
CH
Chen
Chien-Hsin
CH
Liu
Fang-I
FI
D051546:Cyclooxygenase 2; D004334:Drug Administration Schedule; D004717:Endometrium / Q000187:drug effects / Q000201:enzymology*; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000378:metabolism*; D008525:Medroxyprogesterone / Q000008:administration & dosage; D008565:Membrane Proteins; D008875:Middle Aged; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*
D004966:Estrogens, Conjugated (USP); D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D008525:Medroxyprogesterone