Percutaneous estradiol/oral micronized progesterone has less-adverse effects and different gene regulations than oral conjugated equine estrogens/medroxyprogesterone acetate in the breasts of healthy women in vivo

Effects of progestogens used in menopause hormone therapy on the normal breast and benign breast disease in postmenopausal women

Hormone replacement therapy in menopause is used to improve climacteric syndrome in women whose quality of life is affected. However, given the wide variety of progestogens available, it is important to evaluate their differential benign changes (radiological, cellular, and clinical) on the breast. This review aimed to determine the different benign changes of progestogens used in postmenopausal combined hormone therapy on the breast (radiological, cellular, and clinical), in women without mammary pathology, in order to establish their safety profile. A systematic review of the literature was carried out with a balanced search strategy for the identification of relevant references in the MEDLINE, BVSalud, EMBASE, ProQuest, and Cochrane databases until November 2019. The search terms used were 'menopause' or 'hormonal replacement therapy' or 'progestins' or 'estrogen' or 'mastodynia' or 'benign breast disease' or 'mammography'. Data were collected from the 'eligible' articles by two researchers (ARF and SHA), and possible discrepancies in inclusion were resolved by consensus. A total of 1886 articles were identified; 60 full-text articles were reviewed, and 17 articles that met the inclusion criteria were included for the qualitative analysis. In conclusion, combined hormone replacement therapy is associated with benign effects on the breast, such as mastodynia and increased mammographic density.

Breast effects of oral, combined 17β-estradiol, and progesterone capsules in menopausal women: a randomized controlled trial

Objective:

To evaluate the effect of a single-capsule, bioidentical 17β-estradiol (E2) and progesterone (P4) hormone therapy on mammograms and breasts in postmenopausal women after 1 year of use.

Methods:

In the 12-month, phase 3, randomized, double-blind, placebo-controlled, multicenter REPLENISH trial, postmenopausal women (40-65 y) with moderate to severe vasomotor symptoms and a uterus were randomized to four active daily dose groups of E2/P4 (TX-001HR) or a placebo group. Mammograms were performed and read locally at screening (or ≤6 months before first dose) and at study end using BI-RADS classification. Incidence of abnormal mammograms and breast adverse events was evaluated.

Results:

All but 8 (0.4%) mammograms at screening were normal (BI-RADS 1 or 2). At 1 year, 39 (2.9%) of the 1,340 study-end mammograms were abnormal (BI-RADS 3 or 4); incidence was 1.7% to3.7% with active doses and 3.1% with placebo. Breast cancer incidence was 0.36% with active doses and 0% with placebo. Breast tenderness was reported at frequencies of 2.4% to 10.8% with active doses versus 0.7% with placebo, and led to eight study discontinuations (1.6% of discontinuations in active groups).

Conclusions:

In this phase 3 trial of a combined E2/P4, results of secondary outcomes suggest that E2/P4 may not be associated with increased risk of abnormal mammograms versus placebo, and the incidence of breast tenderness was low relative to most of the rates reported in other studies using hormone therapy.

Changes in breast density during hormone treatment with transdermal estrogens alone or in combination with progesterone

A retrospective observational study to assess whether hormonal treatment (HT) with transdermal estrogens alone or in combination with micronized progesterone increases breast density and to compare these changes to those of a control group of 4120 patients were not given HT. We included 150 patients whose baseline breast density was assessed with photon-counting spectral mammography and 1 year after hormone treatment. The reduction in breast density was compared using an analysis of covariance. The difference in breast density between mammographies in the HT group was -0.40 ± 5.5 and -0.85 ± 4.2 in the control group. The changes in density according to the type of HT, we found that women on treatment with estrogen alone presented a difference of 0.44 ± 5.8, and -1.35 ± 5 (p = 0.13) in women on combined treatment. After adjusting changes in density for age and average number of days between mammographies, we observed a difference of -0.36 95% confidence intervals (CI) [-1.04 to -0.31] in the women on HT and -0.71 95% CI [-1.65 to -0.21] in the control group. No increased breast density was observed in women on HT treatment, nor did we observe an increase according to HT type. The difference in breast density loss was smaller in the HT group versus the control group.

Co-administering Melatonin With an Estradiol-Progesterone Menopausal Hormone Therapy Represses Mammary Cancer Development in a Mouse Model of HER2-Positive Breast Cancer

Melatonin has numerous anti-cancer properties reported to influence cancer initiation, promotion, and metastasis. With the need for effective hormone therapies (HT) to treat menopausal symptoms without increasing breast cancer risk, co-administration of nocturnal melatonin with a natural, low-dose HT was evaluated in mice that develop primary and metastatic mammary cancer. Individually, melatonin (MEL) and estradiol-progesterone therapy (EPT) did not significantly affect mammary cancer development through age 14 months, but, when combined, the melatonin-estradiol-progesterone therapy (MEPT) significantly repressed tumor formation. This repression was due to effects on tumor incidence, but not latency. These results demonstrate that melatonin and the HT cooperate to decrease the mammary cancer risk. Melatonin and EPT also cooperate to alter the balance of the progesterone receptor (PR) isoforms by significantly increasing PRA protein expression only in MEPT mammary glands. Melatonin significantly suppressed amphiregulin transcripts in MEL and MEPT mammary glands, suggesting that amphiregulin together with the higher PRA:PRB balance and other factors may contribute to reducing cancer development in MEPT mice. Melatonin supplementation influenced mammary morphology by increasing tertiary branching in the mouse mammary glands and differentiation in human mammary epithelial cell cultures. Uterine weight in the luteal phase was elevated after long-term exposure to EPT, but not to MEPT, indicating that melatonin supplementation may reduce estrogen-induced uterine stimulation. Melatonin supplementation significantly decreased the incidence of grossly-detected lung metastases in MEL mice, suggesting that melatonin delays the formation of metastatic lesions and/or decreases aggressiveness in this model of HER2⁺ breast cancer. Mammary tumor development was similar in EPT and MEPT mice until age 8.6 months, but after 8.6 months, only MEPT continued to suppress cancer development. These data suggest that melatonin supplementation has a negligible effect in young MEPT mice, but is required in older mice to inhibit tumor formation. Since melatonin binding was significantly decreased in older mammary glands, irrespective of treatment, melatonin supplementation may overcome reduced melatonin responsiveness in the aged MEPT mice. Since melatonin levels are known to decline near menopause, nocturnal melatonin supplementation may also be needed in aging women to cooperate with HT to decrease breast cancer risk.

Evidence on the use of progesterone in menopausal hormone therapy

A need exists for a regulatory agency-approved hormone therapy (HT) with naturally occurring hormones combining progesterone (P4) and estradiol (E2), since no single product contains both endogenous hormones. Many women choose HT with P4 and millions of women around the world are using unapproved, poorly regulated compounded HT. The use of natural P4 in HT results, for the most part, in favorable outcomes without deleterious effects, as shown in clinical studies of postmenopausal women. Importantly, P4 used in HT prevents endometrial hyperplasia from estrogens while helping relieve vasomotor symptoms and improving quality-of-life measures. Additionally, risk of venous thromboembolism and breast cancer does not appear to increase with use of P4 plus estrogens as shown with synthetic progestins plus estrogens in large observations studies, and no detrimental effects of P4 in HT have been found on outcomes related to cardiovascular disease or cognition. A regulatory agency-approved HT with naturally occurring E2/P4 could be an option for the millions of women who desire a bioidentical product and/or are exposed to potential risks of inadequately studied and under-regulated compounded HT.

The impact of micronized progesterone on breast cancer risk: a systematic review

Postmenopausal women with an intact uterus using estrogen therapy should receive a progestogen for endometrial protection. The debate on bioidentical hormones including micronized progesterone has increased in recent years. Based on a systematic literature review on the impact of menopausal hormone therapy (MHT) containing micronized progesterone on the mammary gland, an international expert panel's recommendations are as follows: (1) estrogens combined with oral (approved) or vaginal (off-label use) micronized progesterone do not increase breast cancer risk for up to 5 years of treatment duration; (2) there is limited evidence that estrogens combined with oral micronized progesterone applied for more than 5 years are associated with an increased breast cancer risk; and (3) counseling on combined MHT should cover breast cancer risk - regardless of the progestogen chosen. Yet, women should also be counseled on other modifiable and non-modifiable breast cancer risk factors in order to balance the impact of combined MHT on the breast.

Suicidal ideation among postmenopausal women on hormone replacement therapy: The Korean National Health and Nutrition Examination Survey (KNHANES V) from 2010 to 2012

BACKGROUND

Suicide is a major public health problem around the world. Some studies have found that hormone replacement therapy (HRT) is associated with depression in postmenopausal women. Depression is a well-known risk factor for suicide; therefore, we investigated the relationship between HRT and suicidal ideation in postmenopausal Korean women.

METHODS

We included 2286 postmenopausal women with or without HRT from the Korean National Health and Nutrition Examination Survey 2010-2012. The use and duration of HRT and mental health status, including stress, depressive mood, and suicidal ideation and attempts, were assessed by self-report questionnaires.

RESULTS

The proportion of participants with depressive mood and suicidal ideation was higher in the HRT group than the non-HRT group (all p values<0.05). As the duration of HRT increased, the percentage of participants with suicidal ideation increased (p for trend=0.006). After adjusting for all covariates, the odds ratio (95% confidence intervals) for suicidal ideation was 1.742 (1.223-2.482) in the women with HRT, compared to women without HRT. HRT duration longer than 10 years was associated with suicidal ideation (odds ratio=2.089 and 95% confidence intervals=1.069-4.084).

LIMITATIONS

The cross-sectional design, a possibility of incorrect answer about menopausal status, and no assessment of the type of HRT are the main limitations of this study.

CONCLUSION

Postmenopausal women receiving HRT, especially for more than 10 years, showed increased suicidal ideation compared with postmenopausal women without HRT. Physicians should pay attention to mood symptoms and suicidal ideation in postmenopausal women with HRT.

EFFICACY OF ESTRADIOL IN PERIMENOPAUSAL DEPRESSION: SO MUCH PROMISE AND SO FEW ANSWERS

BACKGROUND

Controversy regarding the antidepressant efficacy of hormone replacement therapy (HRT) stems almost from its inception and reflects the same methodological inconsistencies that have compromised efforts to determine whether the perimenopause is accompanied by an increase in mood symptoms or depression. Methodologic differences of note (other than study design) include menopausal state (perimenopause vs. postmenopause), determination of state (earlier studies used age as a proxy measure), baseline symptomatology (asymptomatic vs. depressive symptoms vs. syndromic depression), route of hormone administration (transdermal vs. oral), and symptom or syndrome measure. Zweifel and O'Brien's 1997 meta-analysis included 26 studies of the effects of menopausal HRT on depressed mood and revealed an overall effect size of 0.68. This moderate to large effect size, showing lower ratings of depressed mood in treated patients compared with controls, implicated HRT as a potential treatment of or prophylactic for depression in menopausal women. Since this publication, multiple studies have aimed to discern the relationship between HRT and menopausal mood.

METHODS

The purpose of this systematic review is to examine the findings and quality of the evidence amassed since Zweifel and O'Brien's meta-analysis.

RESULTS

Of the 24 studies meeting criteria for review, only five RCTs examined depressed subjects, and only two of the study samples were solely perimenopausal.

CONCLUSIONS

One can generalize from the studies reviewed here only with great caution, but there is little evidence to support the use of estradiol to improve mood in nondepressed patients (not surprisingly) and some evidence to support the antidepressant efficacy of estradiol in perimenopausal but not postmenopausal women.

Is breast cancer risk the same for all progestogens?

The population-based case–control study CECILE investigated the impact of various menopausal hormone therapy (MHT) products on breast cancer (BC) risk in 1,555 postmenopausal women [1]. The case group (n = 739) included incident cases of in situ (!) or invasive BC in postmenopausal women. The control group (n = 816) included women from the general population within predefined quotas by age and socio-economic status (SES). While quotas by age were applied to obtain similar distributions by age among controls and among cases, quotas by SES in control women were applied to reflect the distribution by SES of women in the general population in the study area. Data of participants were obtained by a structured questionnaire during in-person interviews, and from pathology reports if applicable, respectively. Women were divided into current and past MHT user. MHTs were classified in estrogen-only therapy (ET), estrogen combined with progestin therapy (EPT) and tibolone. EPT was subdivided in three subtypes according to the progestogen constituent: natural micronized progesterone, progesterone derivatives, and testosterone derivatives. In comparison to never MHT users, any current or past MHT use (ET, EPT, tibolone) was not associated with an increased BC risk. However, in subanalysis BC risk was significantly increased for current use of EPT for 4 or more years (n = 73 cases and n = 56 controls, adjusted OR 1.55; 95 % CI 1.02–2.36). Within the group of current EPT users for 4 or more years, 14 cases had used estrogens combined with micronized progesterone (n = 17 controls), and 55 a combination with a synthetic progestogen (n = 34 controls), respectively. Compared to never MHT use, current use of EPT containing a synthetic progestogen for 4 or more years was associated with a significantly increased BC risk (adjusted OR 2.07; 95 % CI 1.26–3.39), but EPT containing micronized progesterone was not (adjusted OR 0.79; 95 % CI 0.37–1.71). 73 % of current MHT users started treatment within the first year of onset of menopause. Early EPT (n = 52 cases and n = 38 controls, adjusted OR 1.65; 95 % CI 1.02–2.69), but not early ET, starters had a significantly higher BC risk compared to never MHT users. In contrast, MHT initiation beyond 1 year after menopause was not associated with an increased BC risk. The authors concluded that: (1) ET and EPT containing natural progesterone did not increase BC risk whereas, (2) BC risk was increased in users of tibolone or EPT containing a synthetic progestogen, respectively, and that (3) MHT use early after onset of menopause was associated with an increased BC risk as compared to women who delay MHT beyond 1 or more years.

Medroxyprogesterone acetate-driven increase in breast cancer risk might be mediated via cross-talk with growth factors in the presence of progesterone receptor membrane component-1

BACKGROUND

The WHI trial suggests an increase of breast cancer in postmenopausal women probably according to the progestogenic compound, i.e. medroxyprogesterone acetate (MPA). However, the mechanism for a possible carcinogenic effect of MPA remains unclear so far. Progesterone receptor membrane component-1 (PGRMC1) may be important in tumorigenesis and thus may increase breast cancer risk. We investigated the influence of MPA alone and in combination with growth factors on breast cancer cells overexpressing PGRMC1.

METHODS

MCF-7 cells were stably transfected with PGRMC1 expression plasmid (WT-12 cells). Cells transfected only with the vector were used as control cells (EVC-cells). Medroxyprogesterone acetate (MPA), norethisterone (NET) and progesterone (P) were tested alone and in combination with a mixture of growth factors. Cell proliferation was measured by MTT assay.

RESULTS

The growth factor mixture (GF) was able to induce cell proliferation in both cell types, however, the effect was much higher in the WT-12 cells. In WT-12 cells both MPA and NET alone significantly increased cell proliferation with values of 40% and 97%, respectively. Progesterone, however, had no effect. In combination with GF MPA significantly further enhanced cell proliferation as compared to the effect of MPA alone and GF alone in both cell lines. NET showed no further increase as compared to NET alone and P had no effect.

CONCLUSIONS

We could demonstrate a significant proliferative effect of MPA when combined with high concentrations of growth factors. This effect was more pronounced in breast cancer cells overexpressing PGRMC1. These results may be of clinical relevance since in the combined WHI trial an increased breast cancer risk was found during treatment with conjugated equine estrogens plus MPA.

HRT: some unresolved clinical issues in breast cancer, endometrial cancer and premature ovarian insufficiency

Many important issues regarding HRT and the management of postmenopausal women are unresolved and require ongoing consideration and some explanation. HRT is only one of many factors affecting the risk of breast cancer and the risk of breast cancer is not increased in past users of HRT. There is seemingly a paradox in the effect of body weight and HRT on breast cancer risk. It is unclear whether the benefit of giving progestin with estrogen to prevent endometrial cancer in HRT outweighs the increased risk of breast cancer. Sequential HRT may not fully prevent endometrial cancer, and continuous combined regimes are to be preferred. The prevention of the consequences of premature ovarian insuffiency, both immediate and long term, has been neglected, and a strong case can be made for estrogen replacement therapy in all women with premature ovarian insuffiency, particularly following bilateral oophorectomy.

Does mammographic density reflect the expression of breast cancer markers?

Mammographic density reflects variation in breast tissue composition as detected on mammogram. It is associated with a number of well-known breast cancer risk factors and itself is considered one of the strongest risk factors for breast cancer. If the expression of several proteins and genes within the breast tissue influences mammographic density in the same way as it influences breast cancer risk, then mammographic density might serve as an intermediate biomarker in future epidemiological studies on breast cancer. This has the potential to provide a quick means for predicting the effect of changes in the breast microenvironment on breast cancer risk without having to wait for an eventual development of breast cancer. In this review, the expression of several proteins and genes (growth factors, enzymes, proteoglycans and pro-inflammatory markers) within the breast tissue is shown to be associated with mammographic density. These proteins and genes are suspected to play a role in breast carcinogenesis. More studies assessing differential expression of proteins and genes in mammary epithelium and stroma and their association with mammographic density among premenopausal and postmenopausal women are required. Identification of proteins and genes influencing mammographic density may provide further insight on the molecular causes of breast cancer.

Megestrol acetate may stimulate the production of insulin-like growth factor 1 in breast tissues of women with breast cancer

In women with breast cancer who were treated with either continuous tamoxifen alone or sequential tamoxifen followed by megestrol acetate (MA), we demonstrated significant positive associations between the breast tumor estrogen receptor (ER) and an increase in serum sex hormone-binding globulin (SHBG) during tamoxifen treatment. We interpreted this as “ER uniformity” in different tissues, e.g., breast, liver. No other associations with ER were found. In the same study, the breast tumor progesterone receptor (PR) was determined. Our aim was to see if there were any associations between PR and endocrine changes during MA treatment.

The breast tumor PR before treatment and serum insulin-like growth factor I (∂IGF-1), steroids, steroid-binding proteins, and insulin before and during treatment were measured in 17 postmenopausal women with breast cancer who were treated sequentially with tamoxifen 40 mg/day followed by MA 160 mg/day in alternating 3-month periods.

During MA treatment periods, the levels of IGF-1 and insulin increased significantly, whereas the levels of androgens, SHBG, corticosteroid-binding globulin, and cortisol decreased significantly. Significant positive correlations were found between the PR content and increments in ∂IGF-1 but not between PR and any other endocrine change.

PR expression in human liver is very weak, but malignant and normal breast tissues secrete considerable amounts of growth hormone and IGF-1 in vitro and in vivo. This activity is stimulated by progestogens. The association between PR and ∂IGF-1 may therefore reflect a direct PR-mediated action of MA on malignant and normal human breast tissues in vivo.