Evolution of breast cancer incidence in relation to hormone replacement therapy use in Belgium

Menopausal hormone therapy use in relation to breast cancer incidence in 11 European countries

INTRODUCTION

The use of menopausal hormone therapy (MHT) has decreased in many countries in the past 10 years. This is a consequence of the initial publication of the results of the Women's Health Initiative (WHI) randomized trial of estrogen plus progestin. In various countries, further studies then analyzed the incidence of breast cancer (BC) in relation to changes in MHT use. Some reported a decreased BC incidence following cessation of MHT, but others did not. This may reflect differences in BC incidence, in MHT use or in confounding factors, but also in study methodology.

AIM

To analyze the changes in BC incidence and MHT use, using the same methodology, in 11 European countries.

MATERIALS & METHOD

We limited the study to women between the ages of 45 and 69. BC incidence data were provided from cancer registries. MHT sales data were extracted from health sales databases for the years 2003-2013. The association between BC incidence and the rate of MHT use during the past year in Europe was assessed using linear mixed models.

RESULTS

A drop in MHT sales was consistent in all countries for the whole period of follow-up. This was not the case for BC incidence. We found no evidence of a relation between BC incidence and MHT sales in the past year, except for sales of tibolone.

CONCLUSIONS

The longer observation period did not confirm the results of studies that had a shorter follow-up, except in relation to tibolone. The role of confounding factors needs to be clarified.

A systematic review of non-hormonal treatments of vasomotor symptoms in climacteric and cancer patients

The cardinal climacteric symptoms of hot flushes and night sweats affect 24-93% of all women during the physiological transition from reproductive to post-reproductive life. Though efficacious, hormonal therapy and partial oestrogenic compounds are linked to a significant increase in breast cancer. Non-hormonal treatments are thus greatly appreciated.

This systematic review of published hormonal and non-hormonal treatments for climacteric, and breast and prostate cancer-associated hot flushes, examines clinical efficacy and therapy-related cancer risk modulation.

A PubMed search included literature up to June 19, 2014 without limits for initial dates or language, with the search terms, (hot flush* OR hot flash*) AND (clinical trial* OR clinical stud*) AND (randomi* OR observational) NOT review). Retrieved references identified further papers. The focus was on hot flushes; other symptoms (night sweats, irritability, etc.) were not specifically screened. Included were some 610 clinical studies where a measured effect of the intervention, intensity and severity were documented, and where patients received treatment of pharmaceutical quality. Only 147 of these references described studies with alternative non-hormonal treatments in post-menopausal women and in breast and prostate cancer survivors; these results are presented in Additional file 1.

The most effective hot flush treatment is oestrogenic hormones, or a combination of oestrogen and progestins, though benefits are partially outweighed by a significantly increased risk for breast cancer development.

This review illustrates that certain non-hormonal treatments, including selective serotonin reuptake inhibitors, gabapentin/pregabalin, and Cimicifuga racemosa extracts, show a positive risk-benefit ratio.

Key points

Several non-hormonal alternatives to hormonal therapy have been established and registered for the treatment of vasomotor climacteric symptoms in peri- and post-menopausal women.

There are indications that non-hormonal treatments are useful alternatives in patients with a history of breast and prostate cancer. However, confirmation by larger clinical trials is required.

Systematic review about breast cancer incidence in relation to hormone replacement therapy use

BACKGROUND

Several studies report a decrease in breast cancer incidence subsequent to the decrease in hormone replacement therapy (HRT) use. But its magnitude and the time-lag may vary between countries. This may reflect differences in populations, previous type and prevalence of HRT use and breast cancer screening.

AIM

To review systematically studies assessing the relation between breast cancer incidence and change of HRT use.

MATERIAL AND METHOD

Descriptive analysis of the methodology of the studies including design limitations and presence of confounding factors, data sources for breast cancer and HRT and regimens of HRT used.

RESULTS AND DISCUSSION

Eighteen articles were selected. Most studies were ecological and confounding factors such as mammography screening and changes in reproductive and lifestyle habits could not be excluded. Sources of data on breast cancer and HRT were heterogeneous and only few data on HRT regimens used were available. Most studies concluded that the decrease in HRT use during the last decade was probably associated with a decrease in breast cancer incidence, especially for women aged 50 years or more.

CONCLUSIONS

Data, mostly from epidemiological studies, suggest that the decrease in breast cancer incidence can be partly attributed to the drop in HRT use. Nevertheless, available studies are hampered by a number of limitations and it remains difficult to evaluate the exact impact of the drop in HRT use on the decrease in breast cancer incidence. Especially, the studies are seldom based on detailed individual data and do not provide information on regimens used, type of cancers and possible confounding factors.

Ginsenoside Rg1 protection against β-amyloid peptide-induced neuronal apoptosis via estrogen receptor α and glucocorticoid receptor-dependent anti-protein nitration pathway

Ginsenoside Rg1 (Rg1) acts as a neuroprotective agent against various insults, however, the underlying mechanism has not been fully elucidated yet. Here, we report that Rg1 protects primary rat cerebrocortical neurons against β-amyloid peptide₂₅₋₃₅ (Aβ₂₅₋₃₅) injury via estrogen receptor α (ERα) and glucocorticoid receptor (GR)-dependent anti-protein nitration pathway. In primary rat cerebrocortical neuron cultures under basal conditions, Rg1 leads to nuclear translocation of ERα and GR, induces related responsive gene PR, pS₂ and MKP-1, SGK transcription. Meantime, Rg1 also increases the basal level of ERK1/2 phosphorylation. In the presence of toxic level of Aβ₂₅₋₃₅, Rg1 maintains ERK1/2 phosphorylation, attenuates iNOS expression, NO production, and inhibits NF-κB nuclear translocation, protein nitration and cell death. The antiapoptotic effects of Rg1 via both ERα and GR were abolished by small interfering RNAs (siRNA). ERK1/2 phosphorylation inhibitor U0126 can block downstream iNOS expression and NO generation. Interestingly, the anti-protein nitration effect of Rg1 is well matched with ERα and GR activation, although its anti-ROS production effect is in an ERα- and GR-independent manner. These results suggest that Rg1 ameliorates Aβ₂₅₋₃₅-induced neuronal apoptosis at least in part by two complementary ERα- and GR-dependent downstream pathways: (1) upregulation of ERK1/2 phosphorylation followed by inhibiting iNOS expression, NO generation and protein tyrosine nitration. (2) reduction NF-κB nuclear translocation. These data provide new understanding into the mechanisms of Rg1 anti-apoptotic functions after Aβ₂₅₋₃₅ exposure, suggesting that ERα and GR-dependent anti-protein tyrosine nitration pathway might take an important role in the neuroprotective effect of Rg1.