In males, androgen can be aromatized into estrogen by aromatase. Estrogen receptors were shown to be present in male-derived human osteoblasts. For males bone is an important target tissue of estrogen. It was demonstrated that deficiency of estrogen or mutation of estrogen receptor gene in males could lead to osteopenia, even osteoporosis. Estrogens are required for the pubertal growth of bone and play important roles in maintenance of bone mass in males.
Androgens ; metabolism ; Animals ; Aromatase ; metabolism ; Bone and Bones ; metabolism ; Estrogens ; metabolism ; Humans ; Male ; Puberty ; metabolism ; Receptors, Estrogen ; metabolism

OBJECTIVETo establish a human breast cancer MCF-7 cell model stably overexpressing the aromatase gene (MCF-7-aromatase) and aromatase inhibitor letrozole-resistant MCF-7 cell model (MCF-7-LR).

METHODSWe utilized the lentivirus-mediated gene transfer approach to establish MCF-7-aromatase cell and MCF-7 cell model stably overexpressing green fluorescent protein (GFP) (MCF-7-GFP). The expression of aromatase in the MCF-7-aromatase and MCF-7-GFP cells was determined by reverse transcription polymerase chain reaction (RT-PCR), real time quantitative PCR (RT-qPCR), Western blot and immunoprecipitation (IP) assay. The proliferative ability in vitro of MCF-7-aromatase and MCF-7-GFP cells treated with testostorone and β-estradiol (E2) was determined by WST-1 cell proliferation assay. The proliferative ability of MCF-7-aromatase cells treated with letrozole was determined by WST-1 assay. The half maximal inhibitory concentration (IC50 value) for letrozole was calculated from the nonlinear regression line of the plot of cell viability (percentage of control) versus letrozole concentration using Graphpad Prism software. MCF-7-aromatase cells were continuously cultured in the presence of testosterone and letrozole, thus letrozole-resistant MCF-7-LR cells were obtained. WST-1 assay was performed to determine their chemoresistance to letrozole.

RESULTSRT-PCR and RT-qPCR results revealed that the mRNA expression of aromatase was significantly increased in the MCF-7-aromatase cells compared with that in the MCF-7-GFP cells. Both Western blot and IP assays showed that the expression of aromatase protein was drastically increased in the MCF-7-aromatase cells, compared with that in the MCF-7-GFP cells. WST-1 assay showed that the cell proliferation rate of MCF-7-aromatase cells treated with 1 and 10 nmol/L testosterone was 1.43- and 1.53-fold higher than that of the control cells, respectively. The proliferation rate of MCF-7-aromatase cells treated with 1 and 10 nmol/L E2 was 1.41- and 1.55-fold higher than that of the control cells, respectively. In contrast, the proliferation rate of MCF-7-GFP cells treated with 10 nmol/L testosterone was 1.12-fold higher than that of the control cells, and the proliferation rate of MCF-7-GFP cells treated with 1 and 10 nmol/L E2 was 1.41- and 1.51-fold higher than that of the control cells, respectively. Letrozole treatment significantly inhibited the testosterone-induced proliferation ability of MCF-7-aromatase cells in a dose-dependent manner and the IC50 value was 5.3 nmol/L. In contrast, letrozole treatment showed no inhibitory effect on the proliferative ability of MCF-7-LR cells and the IC50 value was >1000 nmol/L.

CONCLUSIONSMCF-7-aromatase and MCF-7-LR cells exhibit different response to letrozole treatment, which provides an important basis for further investigating the mechanism of letrozole resistance.

Antineoplastic Agents ; pharmacology ; Aromatase ; metabolism ; Aromatase Inhibitors ; pharmacology ; Breast Neoplasms ; Cell Proliferation ; Drug Resistance, Neoplasm ; Humans ; MCF-7 Cells ; Models, Biological ; Nitriles ; pharmacology ; Triazoles ; pharmacology

OBJECTIVETo explore the expressions of endothelial nitric oxide synthase (eNOS) and cytochrome P450 (aromatase) in the testis of sexually mature male SD rats and their significance.

METHODSEighteen male SD rats, 6 five-week, 6 seven-week and 6 ten-week old, were selected for this study. Paraffin sections of the left testis were made and the expressions of eNOS and P450 observed by the immunohistochemical ABC method.

RESULTSPositive expressions of eNOS and P450 were found to be + + +, + and + + in the Leydig cells of the five-week, seven-week and ten-week old rats, respectively, and they were also observed in a few spermatocytes, though with no regularity.

CONCLUSIONIn the Leydig cells of sexually mature male SD rats, eNOS and P450 are differently expressed in different stages of sexual maturation, and they are correlated as well.

Animals ; Aromatase ; metabolism ; Male ; Nitric Oxide Synthase Type III ; metabolism ; Rats ; Rats, Sprague-Dawley ; Sexual Maturation ; Testis ; metabolism

OBJECTIVETo investigate the expression status of the P450arom mRNA in breast tissue of pubertal mammary hypertrophy and then explore the possible etiology of pubertal mammary hypertrophy.

METHODS15 patients were selected for pubertal mammary hypertrophy group. Breast hypertrophy tissue specimens were collected from the gland excised during reduction mammaplasty. 15 patients with pathologically simple fibroadenoma were used as another control group. Patient approval of participation in this study was obtained preoperatively. The expression of P450arom mRNA was detected by RT-PCR in all the cases above.

RESULTSThere was no significant difference between the pubertal mammary hypertrophy groups and normal groups on the expression rates of P450arom mRNA. But among the positive cases, the expression of P450arom mRNA within breast tissue were 0.202 +/- 0.048 in pubertal mammary hypertrophy group; and 0.159 +/- 0.068 in normal group. There was significant difference between the pubertal mammary hypertrophy and normal groups (P < 0.05).

CONCLUSIONThe expression of P450arom mRNA in pubertal mammary hypertrophy are significantly higher than in normal mammary glandular tissue. The pubertal mammary hypertrophy may be related to the expression status of P450arom mRNA within breast tissue.

Adolescent ; Adult ; Aromatase ; genetics ; metabolism ; Breast ; metabolism ; pathology ; Female ; Humans ; Hypertrophy ; metabolism ; pathology ; Puberty ; RNA, Messenger ; genetics ; Young Adult

OBJECTIVETo study the effects of aromatase on breast cancer proliferation and invasive ability, so as to detect the relationship between in situ estrogen levels and molecular biological characteristics of breast cancer.

METHODSBy immunohistochemistry staining, the expression of aromatase, matrix metalloproteinases 2 (MMP2) and matrix metalloproteinases (MMP 9) in the primary breast cancers were detected, the associations between aromatase and MMPs as well as clinical-pathological factors were analyzed.

RESULTSThe positive rates of aromatase were 25.0% (+) and 29.9% (++). Aromatase status was associated with MMP2, MMP9 and co-expression of MMP2 and MMP9 (P < 0.05), but not associated with tumor size, ER/PR status, menopausal status and tumor grade (P > 0.05). In the postmenopausal patients there was a relationship between aromatase and tumor size (P < 0.05), but not in the premenopausal patients (P > 0.05); there was a relationship between aromatase and co-expression of MMP2/MMP9 in the patients with ER and/or PR positive (P < 0.05), but not in the patients with ER and PR negative (P > 0.05).

CONCLUSIONSIn the breast cancer in situ estrogen produced by tumor aromatase may promote the cancer cells proliferation and invasiveness and maybe through ER pathway especially in the postmenopausal patients.

Adult ; Aged ; Aromatase ; metabolism ; Breast Neoplasms ; enzymology ; metabolism ; pathology ; Female ; Humans ; Immunohistochemistry ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Middle Aged ; Receptors, Estrogen ; metabolism ; Receptors, Progesterone ; metabolism

OBJECTIVETo study the effects of Wenyang Shengjing Decoction (WSD) containing serum on the estradiol (E2) secretion, the synthesized cytochrome P450 aromatase (P450arom) activities, as well as the expression of its encode gene CYP19 in Leydig cells of male sterile rats of adenine induced Shen-yang deficiency (SYD).

METHODSExperimental rats were randomly divided into 4 groups, i.e., the normal control group, the high, middle, and low dose WSD groups, 5 in each group. The normal saline, low, middle, and high dose WSD were respectively given to rats of all groups for 10 successive days. Blood was drawn from rats' heart 2 h after the last gastrogavage. The serum was separated after centrifuge. Leydig cells isolated and purified from SYD rats were primary cultured in vitro and divided into 5 groups in random, i. e., the blank control group, the model group, the high, middle, and low dose WSD groups (1.2, 1.0, and 0.8 g/mL, respectively). The content of E2 released in the culture supernate was determined by radioimmunoassay. The P450arom activity was detected by tritium release assay. Meanwhile, the mRNA and protein expressions of CYP19 were analyzed using fluorescent quantitative PCR and Western blot respectively.

RESULTSCompared with the blank control group, the E2 secretion of the supernate of Leydig cells obviously decreased in the model groups, accompanied with the inhibition of P450arom activities, significant decreased protein and mRNA expressions of CYP19 (P < 0.01, P < 0.05). Compared with the model group, after intervened by WSD containing serum, the E2 secretion in the Leydig cells could be significantly increased, the P450arom activities up-regulated, the CYP19 expressions up-regulated at the protein and mRNA levels partially in a dose-dependent manner (P < 0.01, P < 0.05).

CONCLUSIONSWSD containing serum could effectively elevate the E2 secretion in Leydig cells, which might be partially achieved through up-regulating P450arom activities and enhancing the gene expression of CyP19. This might be one of its mechanisms of action for treating male infertility of SYD.

Animals ; Aromatase ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Estradiol ; secretion ; Leydig Cells ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Serum ; Yang Deficiency ; metabolism

Aromatase deficiency (AD) is a rare autosomal recessive genetic disease caused by loss-of-function mutations in aromatase gene (CYP19A1), leading to congenital estrogen deficiency syndrome. Both mothers of AD patients during pregnancy and female AD fetus show virilization, while male patients are usually diagnosed in adulthood due to continued height increase and metabolic abnormalities. In 2019, a patient with AD was admitted in the Second Xiangya Hospital. The patient was a 37-year-old adult male who continued to grow linearly after adulthood. His estradiol was below the measurable line, the follicle-stimulating hormone (FSH) increased, bone age delayed, epiphysis unfused, and the bone mass reduced. CYP19A1 gene detection showed that c.1093C>T, p.R365W was homozygous mutation. This disease is rare in clinic. Clinicians need to raise awareness of the disease for early diagnosis and treatment to improve the long-term prognosis of patients.
46, XX Disorders of Sex Development/genetics* ; Adult ; Aromatase/metabolism* ; Female ; Gynecomastia/genetics* ; Humans ; Infertility, Male ; Male ; Metabolism, Inborn Errors ; Mutation ; Pregnancy

OBJECTIVETo investigate the expression of aromatase P450 in the mammary gland of hypertrophic breast.

METHODSThe expression of aromatase P450 in the mammary gland was detected by SP immunohistochemistry in 28 cases of hypertrophic breasts and 12 cases of normal volume breasts. The results were analysed by SPSS 13.0, and comparison among groups was performed by Fisher's exact test.

RESULTSThe positive expression rate of aromatase P450 in hypertrophic group was 39.29%, while there was no positive expression in normal group, showing a significant difference between the two groups (P < 0.05). There was no significant difference between the gland hyperplasia group and adipose hyperplasia group (P > 0.05). There were also no significant difference between the groups with different lactation history or different extent of hypertrophy and mastocytosis (P > 0.05).

CONCLUSIONSOverexpression of aromatase P450 in mammary gland may be related to the development of hypertrophic breast.

Adolescent ; Adult ; Aromatase ; biosynthesis ; Breast Diseases ; metabolism ; pathology ; Case-Control Studies ; Female ; Humans ; Immunohistochemistry ; Mammary Glands, Human ; metabolism ; pathology ; Young Adult

OBJECTIVE: To investigate the therapeutic mechanism of letrozole, the third-generation aromatase inhibitor, on endometriotic lesions in a rat model and its effect on the apoptosis of ectopic endometrial cells. METHODS: Endometriosis was induced by autotransplanting pieces of uterus onto the peritoneum in rats. The rats with successful ectopic implants were divided into 2 groups: A letrozole group (n=15) and a control group (n=15). The volume, appearance, and histopathology of ectopic implant were determined before and after the treatment. Expression of P450arom, COX-2, bcl-2, and bax in the ectopic implant was detected by immunohistochemistry and RT-PCR in the 2 groups. RESULTS: The volume of ectopic implant in the letrozole group was significantly reduced compared with the control group (P<0.05). The protein and mRNA levels of P450arom and COX-2 in the ectopic implant were significantly decreased in the letrozole group compared with the control group (P<0.05). There was a positive correlation between the expression of P450arom and the expression of COX-2 (r=0.943, P<0.001; r=0.913, P<0.001). The protein and mRNA expression of bcl-2 was significantly decreased (P<0.05), and the bax protein and mRNA expression was significantly increased (P<0.05) in the ectopic implant with an increased bax/bcl-2 ratio in the letrozole group compared with the control group (P<0.05). CONCLUSION Letrozole can obviously reduce the size of ectopic implant through decreasing P450arom and COX-2 expression, suppressing the secretion of estrogen, inhibiting the proliferation, and inducing the apoptosis of ectopic implants.
Animals ; Apoptosis ; drug effects ; Aromatase ; metabolism ; Aromatase Inhibitors ; therapeutic use ; Cyclooxygenase 2 ; metabolism ; Endometriosis ; drug therapy ; pathology ; Endometrium ; metabolism ; pathology ; Female ; Letrozole ; Nitriles ; therapeutic use ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Triazoles ; therapeutic use ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo explore the effect mechanism of Sanlengwan (SLW) on estrogen production in ectopic endometrium of rats.

METHODThe rat model of endometriosis was established by surgical implant of endometrial tissue which belong to its body. Forty EMS model rats were randomly divided into five groups (n = 8): model control group, three different concentration SLW groups and anastrozole group. Meanwhile, eight normal rats were used as the normal control group. All the rats were treated for 4 weeks respectively, the changes of the P450 arom and cyclooxygenase-2 protein were measured by immunohistochemical test and western blot respectively before and after treatment of SLW, and the level of secretion of estrodiol and prostaglandin E2 was also measured by ECLIA and RIA.

RESULTSLW can reduce the expression of P450 arom protein, and the levels of estradiol after treatment of SLW were significantly lower than that of the model group in ectopic endometrial tissue (P < 0. 05); The high dose group of SLW can inhibit the expression of cyclooxygenase-2 protein and also reduce the production of prostaglandin E2 (P < 0.05).

CONCLUSIONSLW can reduce the production of estradiol in the ectopic endometrial tissue of rats, and its mechanism might be associated with inhibiting the expression of P450 arom and interruption the positive feedback loop of estradiol production.

Animals ; Aromatase ; metabolism ; Aromatase Inhibitors ; pharmacology ; Cyclooxygenase 2 ; metabolism ; Cyclooxygenase 2 Inhibitors ; pharmacology ; Cytochrome P-450 Enzyme System ; metabolism ; Dinoprostone ; biosynthesis ; Dose-Response Relationship, Drug ; Endometriosis ; enzymology ; pathology ; Endometrium ; drug effects ; metabolism ; Estradiol ; biosynthesis ; Female ; Gene Expression Regulation, Enzymologic ; drug effects ; Rats ; Rats, Wistar