Hormone replacement therapy and the risk of breast cancer

Use of personal care product mixtures and incident hormone-sensitive cancers in the Sister Study: A U.S.-wide prospective cohort

BACKGROUND

Personal care products (PCPs), a source of endocrine-disrupting chemical exposure, may be associated with the risk of hormone-sensitive cancers. Few studies have investigated associations for PCP use with the incidence of hormone-sensitive cancers or considered the joint effect of multiple correlated PCPs. We examined associations between frequently used, or "everyday", PCPs and incident cancers of the breast, ovary, and uterus with a fucus on the joint effect of multiple product exposure.

METHODS

Sister Study participants (n=49 899) self-reported frequency of use in the year before enrollment (2003-2009) for 41 PCPs. Using five-level frequency categories based on questionnaire options, hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for the associations between multiple PCP use and incident breast, ovarian, and uterine cancer using quantile-based g-computation with Cox proportional hazards regression as the underlying model. Multiple PCP use was examined using groupings (beauty, hygiene, and skincare products) determined by both a priori knowledge and Spearman correlation coefficients for co-occurring product use. Associations between individual PCPs and the three cancers were also examined using Cox proportional hazards models coupling with Benjamini-Hochberg procedure for multiple comparisons.

RESULTS

Over an average of 11.6 years, 4 226 breast, 277 ovarian, and 403 uterine cancer cases were identified. Positive associations were observed between the hygiene mixture and ovarian cancer (HR=1.35, 95%CI=1.00, 1.83) and the beauty mixture with postmenopausal breast cancer (HR=1.08, 95%CI=1.01, 1.16). Additionally, we observed an inverse association between the skincare mixture and breast cancer (HR=0.91, 95%CI=0.83, 0.99). No significant associations were observed for individual products after corrected for multiple comparison.

CONCLUSIONS

Findings from this multi-product, joint-effect approach contribute to the growing body of evidence for associations between PCPs and breast cancer and provides novel information on ovarian and uterine cancer.

Interplay between Estrogen, Kynurenine, and AHR Pathways: An immunosuppressive axis with therapeutic potential for breast cancer treatment

Breast cancer is one of the most common malignancies among women worldwide. Estrogen exposure via endogenous and exogenous sources during a lifetime, together with environmental exposure to estrogenic compounds, represent the most significant risk factor for breast cancer development. As breast tumors establish, multiple pathways are deregulated. Among them is the aryl hydrocarbon receptor (AHR) signaling pathway. AHR, a ligand-activated transcription factor associated with the metabolism of polycyclic aromatic hydrocarbons and estrogens, is overexpressed in breast cancer. Furthermore, AHR and estrogen receptor (ER) cross-talk pathways have been observed. Additionally, the Tryptophan (Trp) catabolizing enzymes indolamine-2,3-dioxygenase (IDO) and tryptophan-2,3-dioxygenase (TDO) are overexpressed in breast cancer. IDO/TDO catalyzes the formation of Kynurenine (KYN) and other tryptophan-derived metabolites, which are ligands of AHR. Once KYN activates AHR, it stimulates the expression of the IDO enzyme, increases the level of KYN, and activates non-canonical pathways to control inflammation and immunosuppression in breast tumors. The interplay between E2, AHR, and IDO/TDO/KYN pathways and their impact on the immune system represents an immunosuppressive axis on breast cancer. The potential modulation of the immunosuppressive E2-AHR-IDO/TDO/KYN axis has aroused great expectations in oncotherapy. The present article will review the mechanisms implicated in generating the immunosuppressive axis E2-AHR-IDO/TDO/KYN in breast cancer and the current state of knowledge as a potential therapeutic target.

Α Humanized RANKL Transgenic Mouse Model of Progestin-Induced Mammary Carcinogenesis for Evaluation of Novel Therapeutics

Receptor activator of nuclear factor-κB ligand (RANKL) is critically involved in mammary gland pathophysiology, while its pharmaceutical inhibition is being currently investigated in breast cancer. Herein, we investigated whether the overexpression of human RANKL in transgenic mice affects hormone-induced mammary carcinogenesis, and evaluated the efficacy of anti-RANKL treatments, such as OPG-Fc targeting both human and mouse RANKL or Denosumab against human RANKL. We established novel MPA/DMBA-driven mammary carcinogenesis models in TgRANKL mice that express both human and mouse RANKL, as well as in humanized humTgRANKL mice expressing only human RANKL, and compared them to MPA/DMBA-treated wild-type (WT) mice. Our results show that TgRANKL and WT mice have similar levels of susceptibility to mammary carcinogenesis, while OPG-Fc treatment restored mammary ductal density, and prevented ductal branching and the formation of neoplastic foci in both genotypes. humTgRANKL mice also developed MPA/DMBA-induced tumors with similar incidence and burden to those of WT and TgRANKL mice. The prophylactic treatment of humTgRANKL mice with Denosumab significantly prevented the rate of appearance of mammary tumors from 86.7% to 15.4% and the early stages of carcinogenesis, whereas therapeutic treatment did not lead to any significant attenuation of tumor incidence or tumor burden compared to control mice, suggesting the importance of RANKL primarily in the initial stages of tumorigenesis. Overall, we provide unique genetic tools for investigating the involvement of RANKL in breast carcinogenesis, and allow the preclinical evaluation of novel therapeutics that target hormone-related breast cancers.

Protaetia brevitarsis Extract Attenuates RANKL-Induced Osteoclastogenesis by Inhibiting the JNK/NF-κB/PLCγ2 Signaling Pathway

Protaetia brevitarsis (PB)-derived bioactive substances have been used as food and medicine in many Asian countries because of their antioxidant, antidiabetic, anti-cancer, and hepatoprotective properties. However, the effect of PB extracts (PBE) on osteoclast differentiation is unclear. In this study, we investigated the effect of PBE on RANKL-induced osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs). To investigate the cytotoxicity of PBE, the viability of BMMs was confirmed via MTT assay. Tartrate-resistant acid phosphatase (TRAP) staining and pit assays were performed to confirm the inhibitory effect of PBE on osteoclast differentiation and bone resorption. The expression levels of osteoclast differentiation-related genes and proteins were evaluated using quantitative real-time PCR and Western blotting. PBE attenuated osteoclastogenesis in BMMs in TRAP and pit assays without cytotoxicity. The expression levels of osteoclast marker genes and proteins induced by RANKL were decreased after PBE treatment. PBE suppressed osteoclastogenesis by inhibiting the RANKL-induced activated JNK/NF-κB/PLCγ2 signaling pathway and the expression of NFATc1 and c-Fos. Collectively, these results suggest that PBE could be a potential therapeutic strategy or functional product for osteoclast-related bone disease.

Association of hormone preparations with bone mineral density, osteopenia, and osteoporosis in postmenopausal women: data from National Health and Nutrition Examination Survey 1999-2018

OBJECTIVE

This study aimed to evaluate the associations of hormone preparations with lumbar spine bone mineral density (BMD), osteopenia, and osteoporosis in postmenopausal women, and whether these impacts persisted after hormone preparations were discontinued.

METHODS

A total of 6,031 postmenopausal women were enrolled and divided into seven groups based on the types of hormone preparations. Among them, 1,996 participants were further divided into a current users (CU) group and a past users (PU) group. Multivariable linear regression models or logistic regression models were used to evaluate the associations of hormone preparation with lumbar spine BMD, osteopenia, and osteoporosis.

RESULTS

Combined oral contraceptive pills, estrogen-only pills, estrogen/progestin combo pills, estrogen-only patches, or the use of more than two kinds of hormone preparations were positively associated with lumbar spine BMD (all P < 0.05). Except for estrogen-only patches, other hormone preparations also had a protective effect against osteopenia (all OR < 1, all P < 0.05), but none of them were associated with osteoporosis prevalence (all P > 0.05). The BMD increased by 0.10 and 0.04 g/cm 2 in the CU and PU groups, respectively, compared with the nonusers group (all P < 0.05). In both the CU and PU groups, the risk of osteopenia was reduced (OR, 0.34 and 0.57, respectively).

CONCLUSIONS

Hormone preparations increase lumbar spine BMD in postmenopausal women and exert a protective effect against osteopenia. These impacts persisted after hormone preparations were discontinued. Hormone preparations, however, were not associated with osteoporosis prevalence.

Current progress on in vitro differentiation of ovarian follicles from pluripotent stem cells

Mammalian female reproduction requires a functional ovary. Competence of the ovary is determined by the quality of its basic unit-ovarian follicles. A normal follicle consists of an oocyte enclosed within ovarian follicular cells. In humans and mice, the ovarian follicles are formed at the foetal and the early neonatal stage respectively, and their renewal at the adult stage is controversial. Extensive research emerges recently to produce ovarian follicles in-vitro from different species. Previous reports demonstrated the differentiation of mouse and human pluripotent stem cells into germline cells, termed primordial germ cell-like cells (PGCLCs). The germ cell-specific gene expressions and epigenetic features including global DNA demethylation and histone modifications of the pluripotent stem cells-derived PGCLCs were extensively characterized. The PGCLCs hold potential for forming ovarian follicles or organoids upon cocultured with ovarian somatic cells. Intriguingly, the oocytes isolated from the organoids could be fertilized in-vitro. Based on the knowledge of in-vivo derived pre-granulosa cells, the generation of these cells from pluripotent stem cells termed foetal ovarian somatic cell-like cells was also reported recently. Despite successful in-vitro folliculogenesis from pluripotent stem cells, the efficiency remains low, mainly due to the lack of information on the interaction between PGCLCs and pre-granulosa cells. The establishment of in-vitro pluripotent stem cell-based models paves the way for understanding the critical signalling pathways and molecules during folliculogenesis. This article aims to review the developmental events during in-vivo follicular development and discuss the current progress of generation of PGCLCs, pre-granulosa and theca cells in-vitro.

Adipose-derived stem cells promote the repair of chemotherapy-induced premature ovarian failure by inhibiting granulosa cells apoptosis and senescence

BACKGROUND

Chemotherapeutic drugs, particularly alkylating cytotoxics such as cyclophosphamide (CTX), play an important role to induce premature ovarian failure (POF). Hormone replacement therapy (HRT) is a widely used treatment to improve hormone secretion. However, the long-term HRT increases the risk of breast cancer and cardiovascular disease are attracting concerns. Therefore, there is an urgent need to develop a safe and effective treatment for POF.

METHOD

Adipose-derived stem cells (ADSCs) were isolated and identified from human adipose tissue. For POF modeling, CTX were intraperitoneal injected into CTX-acute group, CTX-chronic group, CTX-acute + ADSCs group and CTX-chronic + ADSCs group rats; For transplantation, ADSCs were transplanted into POF rats through tail-vein. The control group rats were injected with PBS. The effects of POF modeling and transplantation were determined by estrous cycle analysis, histopathological analysis, immunohistochemical staining and apoptosis-related marker. To evaluate the effects of ADSC on granulosa cells in vitro, CTX-induced senescent KGN cells were co-cultured with ADSCs, and senescent-related marker expression was investigated by immunofluorescent staining.

RESULTS

In vivo studies revealed that ADSCs transplantation reduced the apoptosis of ovarian granulosa cells and secretion of follicle-stimulating hormone. The number of total follicles, primordial follicles, primary follicles, and mature follicles and secretion of anti-Müllerian hormone and estradiol (E2) were also increased by ADSCs. The estrous cycle was also improved by ADSC transplantation. Histopathological analysis showed that CTX-damaged ovarian microenvironment was improved by ADSCs. Furthermore, TUNEL staining indicated that apoptosis of granulosa cells was decreased by ADSCs. In vitro assay also demonstrated that ADSC markedly attenuated CTX-induced senescence and apoptosis of granulosa cell. Mechanistically, both in vivo and in vitro experiments proved that ADSC transplantation suppressed activation of the PI3K/Akt/mTOR axis.

CONCLUSION

Our experiment demonstrated that a single injection of high-dose CTX was a less damaging chemotherapeutic strategy than continuous injection of low-dose CTX, and tail-vein injection of ADSCs was a potential approach to promote the restoration of CTX-induced POF.

Genistein Modified with 8-Prenyl Group Suppresses Osteoclast Activity Directly via Its Prototype but Not Metabolite by Gut Microbiota

Postmenopausal osteoporosis is a significant threat to human health globally. Genistein, a soy-derived isoflavone, is regarded as a promising anti-osteoporosis drug with the effects of promoting osteoblastogenesis and suppressing osteoclastogenesis. However, its oral bioavailability (6.8%) is limited by water solubility, intestinal permeability, and biotransformation. Fortunately, 8-prenelylated genistein (8PG), a derivative of genistein found in Erythrina Variegate, presented excellent predicted oral bioavailability (51.64%) with an improved osteoblastogenesis effect, although its effects on osteoclastogenesis and intestinal biotransformation were still unclear. In this study, an in vitro microbial transformation platform and UPLC-QTOF/MS analysis method were developed to explore the functional metabolites of 8PG. RANKL-induced RAW264.7 cells were utilized to evaluate the effects of 8PG on osteoclastogenesis. Our results showed that genistein was transformed into dihydrogenistein and 5-hydroxy equol, while 8PG metabolites were undetectable under the same conditions. The 8PG (10^-6 M) was more potent in inhibiting osteoclastogenesis than genistein (10^-5 M) and it down-regulated NFATC1, cSRC, MMP-9 and Cathepsin K. It was concluded that 8-prenyl plays an important role in influencing the osteoclast activity and intestinal biotransformation of 8PG, which provides evidence supporting the further development of 8PG as a good anti-osteoporosis agent.

MCU Inhibitor Ruthenium Red Alleviates the Osteoclastogenesis and Ovariectomized Osteoporosis via Suppressing RANKL-Induced ROS Production and NFATc1 Activation through P38 MAPK Signaling Pathway

Osteoporosis is a disorder of bone metabolism that is extremely common in elderly patients as well as in postmenopausal women. The main manifestation is that the bone resorption capacity is greater than the bone formation capacity, which eventually leads to a decrease in bone mass, increasing the risk of fracture. There is growing evidence that inhibiting osteoclast formation and resorption ability can be effective in treating and preventing the occurrence of osteoporosis. Our study is the first time to explore the role of the mitochondrial calcium uniporter (MCU) and its inhibitor ruthenium red (RR) in bone metabolism, clarifying the specific mechanism by which it inhibits osteoclast formation in vitro and plays a therapeutic role in osteoporosis in vivo. We verified the suppressive effects of RR on the receptor activator of nuclear factor-κB ligand (RANKL-)-induced differentiation and bone resorption function of osteoclasts in vitro. The reactive oxygen species (ROS) production stimulated by RANKL and the expression level of P38 MAPK/NFATc1 were also found to be inhibited by RR. Moreover, the promotion of RR on osteogenesis differentiation was investigated by alkaline phosphatase (ALP) and alizarin red S (ARS) staining and the detection of osteogenesis-specific gene expression levels by quantitative polymerase chain reaction (qPCR) and western blotting. Moreover, in ovariectomy (OVX-)-induced osteoporosis models, RR can downregulate the expression and function of the MCU, relieving bone loss and promoting osteogenesis to present a therapeutic effect on osteoporosis. This new finding will provide an important direction for the study of RR and MCU in the study of bone metabolism therapy targets.

A Systematic Review and Meta-Analysis of Phytoestrogen Protects Against Myocardial Ischemia/Reperfusion Injury: Pre-Clinical Evidence From Small Animal Studies

Background: Phytoestrogens are a class of natural compounds that have structural similarities to estrogens. They have been identified to confer potent cardioprotective effects in experimental myocardial ischemia-reperfusion injury (MIRI) animal models. We aimed to investigate the effect of PE on MIRI and its intrinsic mechanisms. Methods: A systematic search was conducted to identify PEs that have been validated in animal studies or clinical studies as effective against MIRI. Then, we collected studies that met inclusion and exclusion criteria from January 2016 to September 2021. The SYRCLE's RoB tool was used to evaluate the quality. Data were analyzed by STATA 16.0 software. Results: The search yielded 18 phytoestrogens effective against heart disease. They are genistein, quercetin, biochanin A, formononetin, daidzein, kaempferol, icariin, puerarin, rutin, notoginsenoside R1, tanshinone IIA, ginsenoside Rb1, ginsenoside Rb3, ginsenoside Rg1, ginsenoside Re, resveratrol, polydatin, and bakuchiol. Then, a total of 20 studies from 17 articles with a total of 355 animals were included in this meta-analysis. The results show that PE significantly reduced the myocardial infarct size in MIRI animals compared with the control group (p < 0.001). PE treatment significantly reduced the creatine kinase level (p < 0.001) and cTnI level (p < 0.001), increased left ventricular ejection fraction (p < 0.001) and left ventricular fractional shortening (p < 0.001) in MIRI animals. In addition, PE also exerts a significant heart rate lowering effect (p < 0.001). Conclusion: Preclinical evidence suggests that PE can be multi-targeted for cardioprotective effects in MIRI. More large animal studies and clinical research are still needed in the future to further confirm its role in MIRI.

Complementary and Alternative Medicine for Premature Ovarian Insufficiency: A Review of Utilization and Mechanisms

Premature ovarian insufficiency (POI) is defined as a decline in ovarian function before the age of 40 and is one of the leading causes of infertility in women. The etiology is complex, and the pathogenesis is not clear. The main treatment is hormone replacement therapy, but a growing body of data confirms that such treatment can increase the risk of endometrial disease and cardiovascular disease. Complementary and alternative medicine (CAM) has been widely used in patients with POI due to its limited adverse reactions and high efficiency. According to literature reports, CAM therapy for POI mainly includes traditional Chinese medicine, acupuncture, psychotherapy, dietary supplements, and exercise therapy. This article reviews the application of CAM in the treatment of POI and attempts to determine the therapeutic effects and the mechanisms behind these effects based on existing clinical and experimental studies in order to provide theoretical support for the treatment of POI.

TrkB agonist antibody ameliorates fertility deficits in aged and cyclophosphamide-induced premature ovarian failure model mice

Premature ovarian failure (POF) is a leading cause of women's infertility without effective treatment. Here we show that intravenous injection of Ab4B19, an agonistic antibody for the BDNF receptor TrkB, penetrates into ovarian follicles, activates TrkB signaling, and promotes ovary development. In both natural aging and cyclophosphamide-induced POF models, treatment with Ab4B19 completely reverses the reduction of pre-antral and antral follicles, and normalizes gonadal hormone. Ab4B19 also attenuates gonadotoxicity and inhibits apoptosis in cyclophosphamide-induced POF ovaries. Further, treatment with Ab4B19, but not BDNF, restores the number and quality of oocytes and enhances fertility. In human, BDNF levels are high in granulosa cells and TrkB levels increase in oocytes as they mature. Moreover, BDNF expression is down-regulated in follicles of aged women, and Ab4B19 activates TrkB signaling in human ovary tissue ex vivo. These results identify TrkB as a potential target for POF with differentiated mechanisms, and confirms superiority of TrkB activating antibody over BDNF as therapeutic agents.

Prognostic value of preoperative low bone mineral density in patients with digestive cancers: a systematic review and meta-analysis

PURPOSE

Osteopenia typically presents low bone mineral density (BMD) and has recently been reported as a prognostic factor in various cancers. However, the prognostic value of osteopenia in digestive tract cancers remains to be defined. We aimed to review the prognostic value of preoperative osteopenia in patients with digestive cancers.

METHODS

Cohort studies evaluating the prognostic value of preoperative osteopenia in digestive cancers (colorectal, esophageal, hepatic, bile duct, and pancreatic cancer) were searched using electronic databases and trial registries. The exposure was defined as low BMD estimated by computed tomography at 11^th thoracic vertebra, while comparator was normal BMD. The primary outcomes were overall survival and recurrence-free survival for osteopenia. Random effect meta-analyses were performed. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to assess the certainty of evidence.

RESULTS

A total of 11 studies (2230 patients) were included. Osteopenia was an independent risk factor for overall survival (hazard ratio [HR] = 2.02, 95% CI = 1.47 to 2.78; I² = 74%), along with sarcopenia. Osteopenia also predicted poor recurrence-free survival (HR = 1.96, 95% CI = 1.36 to 2.81; I² = 85%). In subgroup analyses, osteopenia predicted prognosis in colorectal, esophageal, hepatic, and bile duct cancers, but not in pancreatic cancer. The certainty of the evidence was low due to inconsistency and publication bias.

CONCLUSION

Osteopenia may be independently associated with poor prognosis in patients with digestive tract cancer. Further studies are needed to establish the relevance of osteopenia in the operative prognosis of these patients.

Triple-Negative Breast Cancer: A Brief Review About Epidemiology, Risk Factors, Signaling Pathways, Treatment and Role of Artificial Intelligence

Triple-negative breast cancer (TNBC) is a kind of breast cancer that lacks estrogen, progesterone, and human epidermal growth factor receptor 2. This cancer is responsible for more than 15–20% of all breast cancers and is of particular research interest as it is therapeutically challenging mainly because of its low response to therapeutics and highly invasive nature. The non-availability of specific treatment options for TNBC is usually managed by conventional therapy, which often leads to relapse. The focus of this review is to provide up-to-date information related to TNBC epidemiology, risk factors, metastasis, different signaling pathways, and the pathways that can be blocked, immune suppressive cells of the TNBC microenvironment, current and investigation therapies, prognosis, and the role of artificial intelligence in TNBC diagnosis. The data presented in this paper may be helpful for researchers working in the field to obtain general and particular information to advance the understanding of TNBC and provide suitable disease management in the future.

Oral contraceptives and risk of breast cancer and ovarian cancer in women with a BRCA1 or BRCA2 mutation: A meta-analysis of observational studies

It remains inconclusive whether the use of oral contraceptives (OCs) alters the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. We investigated the association between OC use and the risks of breast or ovarian cancer in this group by using a meta-analysis. PubMed and EMBASE were searched using keywords until February 2021 to identify relevant studies that evaluated the association between OC ever use and the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. Twelve studies for breast cancer and eight studies for ovarian cancer were identified. In the random-effects meta-analysis, the ever use of OCs was significantly associated with an increased risk of breast cancer [odds ratio (OR), relative risk (RR), or hazard ration (HR) = 1.24; 95% confidence interval (CI) 1.08 - 1.41] and a decreased risk of ovarian cancer (OR/RR/HR = 0.53, 95% CI 0.41 - 0.67). Consistent findings were observed, when BRCA1 and BRCA2 mutation carriers were analyzed separately. The increased risk of breast cancer was observed only in the long-term (>5 years) users of OCs, while the decrease risk of ovarian cancer was observed regardless of the duration of OC use. The current study suggests that the ever use of OCs in BRCA mutation carriers is significantly associated with an increased risk of breast cancer and a decreased risk of ovarian cancer. Therefore, the use of OCs as chemoprevention of ovarian cancer should be cautious in BRCA mutation carriers.

Case report: acromegaly and breast cancer in a woman with turner syndrome

PURPOSE

To present a case with a woman with Turner syndrome (TS) with acromegaly and breast cancer, in her medical history.

METHOD

A descriptive case report of a single patient.

RESULTS

The woman had short stature and lack of puberty and was not treated with hormones. When she was 36-year-old, acromegaly was diagnosed. She was treated with transsphenoidal surgery, followed by external radiation on the adenoma, without any affection on the pituitary gland. Annual controls revealed ordinary pituitary axes during 40 years' follow-up. She was treated for hypertension, had an aortic dilatation and started menopausal hormone therapy (MHT),1 mg estradiol and 0.5 mg norethisterone acetate daily, at the age of 50, due to osteoporosis. At the age of 60, she was diagnosed with breast cancer at the mammography screening. After, mastectomy, neoadjuvant radiation, and treatment with tamoxifen citrate were given due to the tubular breast cancer.

CONCLUSIONS

Despite a possible growth hormone (GH) resistance and lack of endogenous estradiol in women with TS, this patient was diagnosed with acromegaly and breast cancer. This case demonstrates the potential for co-occurring two hormonally active tumors in a woman with TS with monosomy karyotype.

Identifying women with increased risk of breast cancer and implementing risk-reducing strategies and supplemental imaging

Breast cancer (BC) is the second most common cancer in women, affecting 1 in 8 women in the United States (12.5%) in their lifetime. However, some women have a higher lifetime risk of BC because of genetic and lifestyle factors, mammographic breast density, and reproductive and hormonal factors. Because BC risk is variable, screening and prevention strategies should be individualized after considering patient-specific risk factors. Thus, health care professionals need to be able to assess risk profiles, identify high-risk women, and individualize screening and prevention strategies through a shared decision-making process. In this article, we review the risk factors for BC, risk-assessment models that identify high-risk patients, and preventive medications and lifestyle modifications that may decrease risk. We also discuss the benefits and limitations of various supplemental screening methods.

Breast Cancer-Epidemiology, Risk Factors, Classification, Prognostic Markers, and Current Treatment Strategies-An Updated Review

Simple Summary

Breast cancer is the most common cancer among women. It is estimated that 2.3 million new cases of BC are diagnosed globally each year. Based on mRNA gene expression levels, BC can be divided into molecular subtypes that provide insights into new treatment strategies and patient stratifications that impact the management of BC patients. This review addresses the overview on the BC epidemiology, risk factors, classification with an emphasis on molecular types, prognostic biomarkers, as well as possible treatment modalities.

Abstract

Breast cancer (BC) is the most frequently diagnosed cancer in women worldwide with more than 2 million new cases in 2020. Its incidence and death rates have increased over the last three decades due to the change in risk factor profiles, better cancer registration, and cancer detection. The number of risk factors of BC is significant and includes both the modifiable factors and non-modifiable factors. Currently, about 80% of patients with BC are individuals aged >50. Survival depends on both stage and molecular subtype. Invasive BCs comprise wide spectrum tumors that show a variation concerning their clinical presentation, behavior, and morphology. Based on mRNA gene expression levels, BC can be divided into molecular subtypes (Luminal A, Luminal B, HER2-enriched, and basal-like). The molecular subtypes provide insights into new treatment strategies and patient stratifications that impact the management of BC patients. The eighth edition of TNM classification outlines a new staging system for BC that, in addition to anatomical features, acknowledges biological factors. Treatment of breast cancer is complex and involves a combination of different modalities including surgery, radiotherapy, chemotherapy, hormonal therapy, or biological therapies delivered in diverse sequences.

Breast cancer incidence and mortality in women in China: temporal trends and projections to 2030

OBJECTIVE

Breast cancer was the most common cancer and the fifth cause of cancer deaths among women in China in 2015. The evaluation of the long-term incidence and mortality trends and the prediction of the future burden of breast cancer could provide valuable information for developing prevention and control strategies.

METHODS

The burden of breast cancer in China in 2015 was estimated by using qualified data from 368 cancer registries from the National Central Cancer Registry. Incident cases and deaths in 22 cancer registries were used to assess the time trends from 2000 to 2015. A Bayesian age-period-cohort model was used to project the burden of breast cancer to 2030.

RESULTS

Approximately 303,600 new cases of breast cancer (205,100 from urban areas and 98,500 from rural areas) and 70,400 breast cancer deaths (45,100 from urban areas and 24,500 from rural areas) occurred in China in 2015. Urban regions of China had the highest incidence and mortality rates. The most common histological subtype of breast cancer was invasive ductal carcinoma, followed by invasive lobular carcinoma. The age-standardized incidence and mortality rates increased by 3.3% and 1.0% per year during 2000-2015, and were projected to increase by more than 11% until 2030. Changes in risk and demographic factors between 2015 and 2030 in cases are predicted to increase by approximately 13.3% and 22.9%, whereas deaths are predicted to increase by 13.1% and 40.9%, respectively.

CONCLUSIONS

The incidence and mortality of breast cancer continue to increase in China. There are no signs that this trend will stop by 2030, particularly in rural areas. Effective breast cancer prevention strategies are therefore urgently needed in China.

Dancing With Health: Quality of Life and Physical Improvements From an EU Collaborative Dance Programme With Women Following Breast Cancer Treatment

Background: Women's health has received renewed attention in the last few years including health rehabilitation options for women affected by breast cancer. Dancing has often been regarded as one attractive option for supporting women's well-being and health, but research with women recovering from breast cancer is still in its infancy. Dancing with Health is multi-site pilot study that aimed to evaluate a dance programme for women in recovery from breast cancer across five European countries.

Methods: A standardized 32 h dance protocol introduced a range of Latin American dances presented within a sports and exercise framework with influences from dance movement therapy. Fifty-four women (M age 53.51; SD 7.99) participated in the study who had a breast cancer diagnosis <3 years, chemotherapy >6 weeks, no indication of metastasis, or scheduled surgery/chemotherapy/radiation treatment for the duration of the intervention. Primary outcome data was collected for anthropometric and fitness measures next to cancer-related quality of life. T-tests and Wilcoxon signed ranked tests were used to establish differences pre and post intervention. Cohen's d was also calculated to determine the effect size of the intervention.

Results: Statistically significant changes were found for: (i) weight, right and left forearm circumference and hip; (ii) 6 min walking, right and left handgrip, sit-to-stand and sit-and-reach; (iii) the EORTC-QLQ C30 summary score as well as the subscales of emotional and social functioning and symptoms. In all cases the direction of change was positive, while Cohen's d calculated showed that the effect of the intervention for these parameters ranged from intermediate to large.

Conclusion: Changes on the above anthropometric, fitness and quality of life measures suggest that the intervention was of value to the participating women recovering from breast cancer. Results also advocate collaborative efforts across countries to further research.

Primary Neuroendocrine Neoplasms of the Breast: Still Open Issues

Neuroendocrine breast tumors represent a rare subtype of breast cancer, accounting for less than 1% of all neuroendocrine neoplasms. Starting from their pathology definition, and going through their prevalence, prognosis and treatment, our knowledge is still really uncertain. In the present short review of the medical literature on this topic, we have evaluated in details their epidemiology, risk factors, pathogenesis, pathology, clinical presentation, radiographic aspects, prognosis, and therapy. We have thus been able to identify a number of open issues regarding primary neuroendocrine neoplasms of the breast that need to be clarified. Our ultimate aim was actually to try to understand whether neuroendocrine neoplasms of the breast can be considered a definite clinical entity and if neuroendocrine differentiation of breast tumors has a really clinical relevance.

A novel strategy for exploring food originated anti-adipogenesis substances and mechanism by structural similarity evaluation, ADME prediction, network pharmacology and experimental validation

Screening potential functional substances based on active compounds is still a challenge faced by researchers since hundreds and thousands of possible compounds exist in natural products (food, herb, etc.). In this study, an integrated strategy by a combination of structural similarity evaluation, ADME (absorption, distribution, metabolism, excretion) prediction, network pharmacology and experimental validation (SANE strategy) was proposed and applied to explore anti-adipogenesis substances. This strategy was divided into four parts: first, potential compounds were screened based on representative active compounds by similarity evaluation and ADME prediction. Second, the activity of targeted compounds was evaluated in vitro based on the molecular biology method. Third, network pharmacology was used to explore potential targets and pathways. Last, the core pharmacological mechanism was confirmed by modern pharmacology methods. As a result, 8-prenylgenistein (8PG) was screened with chemical structure similarity with genistein and improved ADME propriety. Meanwhile, 8PG was found to present significant anti-adipogenesis effects in pre-adipocyte 3T3-L1 cells and primary human bone marrow stromal cells (hBMSC). Through using methods including: chemical staining, functional assays, and Real time PCR, 8PG was found to present more potency than genistein in suppressing the adipocyte differentiation. Further, the potential pharmacological mechanism was predicted, and significant effects of 8PG on activating the Wnt/β-catenin pathway in 3T3-L1 cells and hBMSC were confirmed by  immunoblotting in the absence/presence of signaling pathway blocker and immunofluorescence staining. A new insight for exploring more potent compounds based on accurate effect compounds is provided in our work. Moreover, a potential compound (8PG), suppressing adipogenesis, was also supplied.

Comparative efficacy, safety, and acceptability of single-agent poly (ADP-ribose) polymerase (PARP) inhibitors in BRCA-mutated HER2-negative metastatic or advanced breast cancer: a network meta-analysis

Background: Breast cancer is the most commonly diagnosed cancer and is the leading cause of cancer death in women worldwide. Both talazoparib and olaparib are approved by the US Food and Drug Administration for treating BRCA (breast cancer 1, early onset)-mutated HER2 (human epidermal growth factor receptor 2)-negative metastatic or advanced breast cancer. However, the optimal choice of first-line treatment has not been determined.

Objective: To compare the efficacy, safety, and acceptability of single-agent poly (ADP-ribose) polymerase (PARP) inhibitors for patients with BRCA-mutated HER2-negative metastatic or advanced breast cancer.

Results: We included two trials comprising 733 participants. Compared with talazoparib, olaparib was not associated with improved PFS (HR = 1.08, 95% CrI = 0.34–3.45) or OS (HR = 1.18, 95% CrI = 0.61–2.31). Compared with talazoparib, olaparib was associated with non-significantly improved ORR (OR = 0.83, 95% CrI = 0.05–12.64). Regarding safety, olaparib had reduced risk for both grade 3–4 anemia (OR = 0.34, 95% CrI = 0.003–34.94) and any-grade anemia (OR = 0.37, 95% CrI = 0.02–6.81) compared with talazoparib. Olaparib also showed a low risk for grade 3–4 neutropenia (OR = 0.57, 95% CrI = 0.06–5.75) compared with talazoparib. Both talazoparib and olaparib were not associated with high risk of treatment discontinuation (OR = 0.95, 95% CrI = 0.21–4.47). Regarding time to QoL deterioration, olaparib was associated with short time to clinically meaningful QoL deterioration (HR = 1.16, 95% CrI = 0.19–7.17) compared to talazoparib.

Conclusion: Both talazoparib and olaparib have similar efficacy, safety, and acceptability in patients with BRCA-mutated HER2-negative metastatic or advanced breast cancer. Well-designed head-to-head randomized controlled trials with large samples are suggested to determine the optimal treatment choice.

Methods: We performed a systematic review and network meta-analysis. We performed a systematic search of Web of Science, Embase, PubMed, Medline, ClinicalTrials.gov, the Cochrane Central Register of Controlled Trials, and the World Health Organization International Clinical Trials Registry Platform, and international registers for published and unpublished double-blind randomized controlled trials from database inception to July 20, 2019. The pooled estimates of hazard ratios (HR) with 95% credible intervals (CrIs) were calculated for PFS, OS, and the time to deterioration of quality of life (QoL). The pooled estimates of odds ratio (OR) with 95% CrIs were calculated for ORR, AEs, and treatment discontinuation. This study is registered with PROSPERO (CRD42019138939).

Use of postmenopausal hormone therapies and risk of histology- and hormone receptor-defined breast cancer: results from a 15-year prospective analysis of NIH-AARP cohort

Background

Menopausal hormone therapy (MHT) increases breast cancer (BC) risk, but cohort studies largely consider use only at enrollment. Evidence is limited on how changes in MHT use alter the magnitude of risk, and whether risk varies between invasive and in situ cancer, by histology or by hormone receptor status.

Methods

We investigated the roles of estrogen-alone therapy (ET) and estrogen plus progestin therapy (EPT) on BC risk overall, by histology and estrogen receptor (ER) and progesterone receptor (PR) status, and on incidence of in situ disease, in the NIH-AARP cohort. Participants included 118,760 postmenopausal women (50–71 years), of whom 63.5% (n = 75,398) provided MHT use information at baseline in 1996 and in a follow-up survey in 2004, subsequent to the dissemination in 2002 of the Women’s Health Initiative trial safety concerns regarding EPT. ET analyses included 50,476 women with hysterectomy (31,439 with follow-up data); EPT analyses included 68,284 women with intact uteri (43,959 with follow-up data). Adjusted hazard ratios (HRs) were estimated using Cox proportional hazards models using age as the time metric with follow-up through 2011.

Results

Eight thousand three hundred thirty-three incident BC cases were accrued, 2479 in women with follow-up data. BC risk was not elevated in current ET users at baseline (HR = 1.05, 95% confidence interval [CI] CI = 0.95–1.16) but was higher in women continuing use through 2004 (HR = 1.35, 95% CI = 1.04–1.75). Ever EPT use at baseline was associated with elevated BC risk overall (HR = 1.54 (1.44–1.64), with a doubling in risk for women with 10 or more years of use, for in situ disease, and across subtypes defined by histology and ER/PR status (all p < 0.004). Risk persisted in women who continued EPT through 2004 (HR = 1.80, 95% CI = 1.39–2.32). In contrast, no association was seen in women who discontinued EPT before 2004 (HR = 1.14, 95% CI = 0.99–1.30).

Conclusions

ET use was not associated with BC risk in this cohort, although excess risk was suggested in women who continued use through 2004. EPT use was linked to elevated in situ and invasive BC risk, and elevated risk across invasive BC histologic and hormone receptor-defined subtypes, with the highest risk for women who continued use through the 2004 follow-up survey.

Supplementary information

The online version contains supplementary material available at 10.1186/s13058-020-01365-9.

Progesterone receptor promotes degradation of STAT2 to inhibit the interferon response in breast cancer

Type I (IFNα/β) interferon signaling represents a critical transduction pathway involved in recognition and destruction of nascent tumor cells. Downregulation of this pathway to promote a more immunosuppressed microenvironment contributes to the ability of tumor cells to evade the immune system, a known Hallmark of Cancer. The present study investigates the progesterone receptor (PR), which is expressed in the vast majority of breast cancers, and its ability to inhibit efficient interferon signaling in tumor cells. We have shown that PR can block the interferon signaling cascade by promoting ubiquitination and degradation of STAT2. Targeting STAT2 is critical, as we show that it is an essential protein in inducing transcription of interferon-stimulated genes (ISG); shRNA-mediated knockdown of STAT2 severely abrogates the interferon response in vitro. Importantly, we were able to reverse this inhibition by treating with onapristone, an anti-progestin currently being investigated in breast cancer clinical trials. Additionally, we have found that an interferon-related gene signature (composed of ISGs) is inversely correlated with PR expression in human tumors. We speculate that PR inhibition of interferon signaling may contribute to creating an immunosuppressed microenvironment and reversal of this through anti-progestins may present a novel therapeutic target to promote immune activity within the tumor.

Effects of Puerarin on the Ovariectomy-Induced Depressive-Like Behavior in ICR Mice and Its Possible Mechanism of Action

Daily treatment of ovariectomized (OVX) ICR mice with puerarin, a glycosyl isoflavone isolated from the root bark of Pueraria candollei var. mirifica, and 17β-estradiol attenuated ovariectomy-induced depression-like behavior, as indicated by a decrease in immobility times in the tail suspension test (TST) and the forced swimming test (FST), an increase in the uterine weight and volume, a decrease in serum corticosterone levels, and dose-dependently normalized the downregulated transcription of the brain-derived neurotrophic factor (BDNF) and estrogen receptor (Erβ and Erα) mRNAs. Like 17β-estradiol, puerarin also inhibited ovariectomy-induced suppression of neurogenesis in the dentate gyrus of the hippocampus (increased the number of doublecortin (DCX)-immunosuppressive cells). These results suggest that puerarin exerts antidepressant-like effects in OVX animals, possibly by attenuating the OVX-induced hyperactivation of the HPA axis and/or normalizing the downregulated transcription of BDNF and ER mRNA in the brain.

Hormone Replacement Therapy After Oophorectomy and Breast Cancer Risk Among BRCA1 Mutation Carriers

Importance

Prophylactic bilateral salpingo-oophorectomy is recommended for BRCA1 mutation carriers to prevent ovarian cancer. Whether or not hormone replacement therapy (HRT) initiated after oophorectomy is associated with an increased risk of breast cancer has not been evaluated in a prospective study.

Objective

To determine the association between HRT use and BRCA1-associated breast cancer.

Design, Setting, and Participants

A prospective, longitudinal cohort study of BRCA1 and BRCA2 mutation carriers from 80 participating centers in 17 countries was conducted between 1995 and 2017 with a mean follow-up of 7.6 years. Participants had sought genetic testing for a BRCA1 or BRCA2 mutation because of a personal or family history of breast and/or ovarian cancer. Carriers of BRCA1 mutation with no personal medical history of cancer who underwent bilateral oophorectomy following enrollment were eligible for the cohort study.

Exposures

A follow-up questionnaire was administered every 2 years to obtain detailed information on HRT use. A left-truncated Cox proportional hazard analysis was used to estimate the hazard ratios (HRs) and 95% CIs associated with the initiation of HRT use postoophorectomy.

Main Outcomes and Measures

Incident breast cancer.

Results

A total of 872 BRCA1 mutation carriers with a mean postoophorectomy follow-up period of 7.6 years (range, 0.4-22.1) were included in this study. Mean (SD) age of participants was 43.4 (8.5) years. Among these, 92 (10.6%) incident breast cancers were diagnosed. Overall, HRT use after oophorectomy was not associated with an increased risk of breast cancer. The HR was 0.97 (95% CI, 0.62-1.52; P = .89) for ever use of any type of HRT vs no use; however, the effects of estrogen alone and combination hormonal therapy were different. After 10 years of follow-up, the cumulative incidence of breast cancer among women who used estrogen-alone HRT was 12% compared with 22% among women who used estrogen plus progesterone HRT (absolute difference, 10%; log rank P = .04).

Conclusions and Relevance

These findings suggest that use of estrogen after oophorectomy does not increase the risk of breast cancer among women with a BRCA1 mutation and should reassure BRCA1 mutation carriers considering preventive surgery that HRT is safe. The possible adverse effect of progesterone-containing HRT warrants further study.

Pituitary Metastases: A Nationwide Study on Current Characteristics With Special Reference to Breast Cancer

OBJECTIVE

To investigate the contemporary presentation of pituitary metastases.

PATIENTS

Thirty-eight patients diagnosed with pituitary metastases from 1996 to 2018 in Sweden.

METHODS

Pituitary metastases were confirmed by histopathology (n = 27) or considered highly likely according to radiological findings, including rapid tumor progression (n = 11). Medical records were reviewed and sellar images reexamined centrally.

RESULTS

Breast and lung cancers were the most common primary tumors, in 45% and 21% of patients, respectively. Sixty-seven percent of breast cancers overexpressed human epidermal growth factor receptor 2 (HER2); 53% of pituitary metastases from breast cancers appeared ≥10 years after diagnosis of the primary tumor. At presentation, 71% appeared to have ACTH deficiency, 65% had TSH deficiency, and 26% had diabetes insipidus. Fatigue, nausea/vomiting, loss of appetite, weight loss, myalgia, and/or arthralgia were reported in 47% of patients with morning cortisol <100 nmol/L vs 23% with cortisol ≥200 nmol/L. Sixteen patients had visual field defects, and eight had diplopia. Intrasellar and suprasellar tumor growth was the most frequent finding. Initially, a pituitary adenoma was considered the etiology in 18% of patients.Radiotherapy, pituitary surgery, and chemotherapy were used in 68%, 68%, and 11% of patients, respectively. One and 2 years after diagnosis of pituitary metastases, 50% and 26% of patients were alive.

CONCLUSION

Pituitary metastases may be mistaken for pituitary adenomas and can appear late, especially in breast cancer. Breast cancers overexpressing HER2 seem prone to metastasize to the pituitary. Hypocortisolism may be misdiagnosed as cancer-related malaise. An increased awareness of pituitary metastases and undiagnosed pituitary failure can improve management in these patients.

Hormone therapy use and breast tissue DNA methylation: analysis of epigenome wide data from the normal breast study

Hormone therapy (HT) is associated with increased risk of breast cancer, strongly dependent on type, duration, and recency of use. HT use could affect cancer risk by changing breast tissue transcriptional programs. We hypothesize that these changes are preceded by changes in DNA methylation. To explore this hypothesis we used histologically normal-appearing breast tissue from the Normal Breast Study (NBS). DNA methylation β-values were obtained using the Illumina HumanMethylation 450 BeadChips for 90 samples including all NBS-participants who used HT within 5 y before surgery. Data were analyzed using the reference-free cell mixture method. Cancer Genome Atlas (TCGA) mRNA-Seq data were used to assess correlation between DNA methylation and gene expression. We identified 527 CpG sites in 403 genes that were associated with ever using HT at genome wide significance (FDR q < 0.05), of these, 68 sites were also significantly associated with duration of use or recency of use. Twelve sites reached significance in all analyses one of which was cg01382688 in ARHGEF4 (p < 1.2x10⁻⁷). Mutations in ARHGEF4 have been reported in breast tumors, but this is the first report of possible breast cancer-related DNA methylation changes. In addition, 22 genes included more than one significant CpG site and a majority of these sites were significantly correlated with gene expression. Although based on small numbers, these findings support the hypothesis that HT is associated with epigenetic alterations in breast tissue, and identifies genes with altered DNA methylation states which could be linked to breast cancer development.

Reducing the Risk of Gynecologic Cancer in Hereditary Breast Ovarian Cancer Syndrome Mutation Carriers: Moral Dilemmas and the Principle of Double Effect

Hereditary breast ovarian cancer (HBOC) syndrome is an autosomal dominant disease linked to mutations in the BRCA1 and BRCA2 genes in 90 percent of affected families. Female mutation carriers are highly susceptible to aggressive, often disseminated, usually fatal pelvic-abdominal carcinomatosis. This cancer risk can be markedly reduced by surgical removal of the internal gynecologic organs before the end of the fourth decade of life and by using estrogen-progestin formulations marketed for many years as combined oral contraceptives (COCs). Both risk-reducing methods are associated with unfavorable effects. Relying on the principle of double effect, this essay argues for the ethical justification of prophylactic surgery and the use of COC to reduce the risk of gynecologic cancer in HBOC syndrome mutation carriers. Summary: Hereditary breast ovarian cancer syndrome is an autosomal dominant disease linked to mutations in the BRCA1 and BRCA2 genes in most affected families. Female mutation carriers are highly susceptible to aggressive, often disseminated, usually fatal pelvic-abdominal carcinomatosis. This cancer risk can be markedly reduced by surgical removal of the internal gynecologic organs before the end of the fourth decade of life and by using estrogen-progestin formulations marketed for many years as combined oral contraceptives. Both risk-reducing methods are associated with unfavorable effects. Relying on the principle of double effect, this essay argues for the ethical justification for those unfavorable effects.

Cardiac autonomic modulation impairments in advanced breast cancer patients

AIM

To compare cardiac autonomic modulation in early- versus advanced-stage breast cancer patients before any type of cancer treatment and investigate associated factors.

METHODS AND RESULTS

This cross-sectional study included women (30-69 years old) with primary diagnosis of breast cancer and women with benign breast tumors. We evaluated cardiac modulation by heart rate variability and assessed factors of anxiety, depression, physical activity, and other relevant medical variables. Patients were divided into three groups based on TNM staging of cancer severity: early-stage cancer (n = 42), advanced-stage cancer (n = 37), or benign breast tumors to serve as a control (n = 37). We analyzed heart rate variability in time and frequency domains. The advanced-stage cancer group had lower vagal modulation than early-stage and benign groups; also, the advance-stage group had lower overall heart rate variability when compared to benign conditions. Heart rate variability was influenced by age, menopausal status, and BMI.

CONCLUSIONS

Heart rate variability seems to be a promising, non-invasive tool for early diagnosis of autonomic dysfunction in breast cancer and detection of cardiovascular impairments at cancer diagnosis. Cardiac autonomic modulation is inversely associated with breast cancer staging.

Interactions of coffee consumption and postmenopausal hormone use in relation to breast cancer risk in UK Biobank

PURPOSE

We investigated the association of coffee consumption with postmenopausal breast cancer risk, overall and by the status of postmenopausal hormone therapy (PMH).

METHODS

This study included 126,182 postmenopausal women (2,636 with breast cancer and 123,546 without) from UK Biobank. Cancer diagnoses were ascertained through the linkage to the UK National Health Service Central Registers. Information on breast cancer risk factors and coffee consumption was collected at baseline and updated during follow-up. We used Cox proportional hazards regression to evaluate associations between coffee consumption and breast cancer, overall and in stratified analyses by woman's PMH status (none, past, current).

RESULTS

In the overall analysis, coffee consumption was not associated with breast cancer risk (Hazard Ratio [HR] 1.00, 95% CI 0.91-1.11 for 2-3 cups/day, and HR 0.98, 95% CI 0.87-1.10 for ≥ 4 cups/day, p-trend = 0.69). Women with no PMH history who consumed ≥ 4 cups/day had a 16% reduced risk of breast cancer as compared to women who consumed < 7 cups/week (HR 0.84, 95% CI 0.71-1.00). Among women with past PMH, those consuming ≥ 4 cups/day had a 22% greater risk of breast cancer than women consuming < 7 cups/week (HR 1.22, 95% CI 1.01-1.47). No association was found among current PMH users. We found no significant interaction between PMH and coffee consumption (p = 0.24).

CONCLUSIONS

Coffee consumption might be associated with increased breast cancer risk in women who used hormones in the past. Further studies are warranted to confirm these findings and elucidate potential biological mechanisms underlying the observed associations.

The Role of Steroid Hormones in Breast and Effects on Cancer Stem Cells

Purpose of Review

This review will discuss how the steroid hormones, estrogen and progesterone, as well as treatments that target steroid receptors, can regulate cancer stem cell (CSC) activity. The CSC theory proposes a hierarchical organization in tumors where at its apex lies a subpopulation of cancer cells endowed with self-renewal and differentiation capacity.

Recent Findings

In breast cancer (BC), CSCs have been suggested to play a key role in tumor maintenance, disease progression, and the formation of metastases. In preclinical models of BC, only a few CSCs are required sustain tumor re-growth, especially after conventional anti-endocrine treatments. CSCs include therapy-resistant clones that survive standard of care treatments like chemotherapy, irradiation, and hormonal therapy.

Summary

The relevance of hormones for both normal mammary gland and BC development is well described, but it was only recently that the activities of hormones on CSCs have been investigated, opening new directions for future BC treatments and CSCs.

Notoginsenoside R1 prevents H9c2 cardiomyocytes apoptosis against hypoxia/reoxygenation via the ERs/PI3K/Akt pathway

Notoginsenoside R₁ (NGR₁) is separate from Panax notoginsenosides (PNS), and plays a role similar to phytoestrogen in preventing and treating cardiovascular diseases. However, the protective mechanism of NGR₁ in the myocardial ischemia/reperfusion injury via the estrogen receptor (ER) pathway remains unclear, which hinder its application. This study aimed to study the preventive mechanisms of NGR₁ in the apoptosis of H9c2 cardiomyocytes after hypoxia/reoxygenation (H/R). NGR₁ did not affect the expression of ERα and ERβ proteins in normal H9c2 cardiomyocytes. However, NGR₁ could upregulate the ERα and G protein-coupled receptor 30 (GPR30) proteins in H9c2 cardiomyocytes after H/R without affecting ERβ levels. Moreover, it significantly affected the expression levels of PI3K and its downstream apoptosis proteins such as Bcl-2 Associated X Protein (Bax), B cell lymphoma/lewkmia-2 (Bcl-2), caspase-3, and so forth. Whereas, after adding the PI3K protein antagonist, the modulatory expression levels of PI3K and its downstream apoptosis proteins were remarkably abolished. After adding ERα and GPR30 antagonists, NGR₁ had no significant effect on the expression of PI3K and its downstream Akt protein in the model group. The data of flow cytometry showed that after adding the ERα, GPR30 and PI3K antagonists, the apoptotic rate of cardiomyocytes had no significant changes compared with the model group. This study demonstrated that NGR₁ protected H9c2 cardiomyocytes from the injury after H/R by affecting ERα and GPR30 to regulate the expression levels of PI3K and its downstream apoptosis proteins.

Notoginsenoside R₁ (NGR₁) is separate from Panax notoginsenosides (PNS), and plays a role similar to phytoestrogen in preventing and treating cardiovascular diseases.

Risk Factors and Preventions of Breast Cancer

Breast cancer is the second leading cause of cancer deaths among women. The development of breast cancer is a multi-step process involving multiple cell types, and its prevention remains challenging in the world. Early diagnosis of breast cancer is one of the best approaches to prevent this disease. In some developed countries, the 5-year relative survival rate of breast cancer patients is above 80% due to early prevention. In the recent decade, great progress has been made in the understanding of breast cancer as well as in the development of preventative methods. The pathogenesis and tumor drug-resistant mechanisms are revealed by discovering breast cancer stem cells, and many genes are found related to breast cancer. Currently, people have more drug options for the chemoprevention of breast cancer, while biological prevention has been recently developed to improve patients' quality of life. In this review, we will summarize key studies of pathogenesis, related genes, risk factors and preventative methods on breast cancer over the past years. These findings represent a small step in the long fight against breast cancer.

Characteristics and Correlates of Woman Eligible for Targeted Screening Mammography in Oman

OBJECTIVES

We sought to determine the characteristics of women eligible for a high-yield screening mammography program in Oman.

METHODS

We conducted a retrospective review of women who underwent breast cancer screening at the Oman Cancer Association from 22 December 2009 to 6 February 2011. Women with a Breast Imaging Reporting and Data System (BI-RADS) score of 4-5 were compared with those with a score of 1-3 based on well-known breast cancer risk factors using the case-control approach analysis.

RESULTS

A BI-RADS score of 4-5 was found in 16.2% of women screened for breast cancer. A higher likelihood of a BI-RADS score of 4 or 5 was observed among women who did not breastfeed (odds ratio (OR) = 2.564; 95% confidence interval (CI): 1.690, 3.890), had their first pregnancy at an older age (OR = 1.062; 95% CI: 1.041, 1.083), used oral contraceptives (OR = 1.397; 95% CI: 1.008, 1.938), and those who reported a positive family history of malignancies (OR = 1.633; 95% CI: 1.285, 2.076). A BI-RADS score of 4 or 5 was significantly less likely in women with a higher number of full-term pregnancies (OR = 0.919; 95% CI: 0.890, 0.948). BI-RADS 4-5 were independently predicted in women with a lower number of full-term pregnancies, did not breastfeed, used oral contraceptives, and who had a positive family history of malignancies. These variables explained 84.0% of the variation in mammogram results.

CONCLUSIONS

In the absence of a national screening program for breast cancer, the high-risk approach for screening should be considered. Women with the above characteristics should be identified and motivated to seek mammogram regularly to warrant a better outcome.

Pregnancy and Breast Cancer

Breast cancer is the most commonly diagnosed type of cancer among women worldwide. The majority of breast cancers are sporadic and the etiology is not well understood. Several factors have been attributed to altering the risk of breast cancer. A full-term pregnancy is a crucial factor in altering the risk. Early full-term pregnancy has been shown to reduce the lifetime risk of breast cancer, while a later first full-term pregnancy increases breast cancer risk. Epidemiological and experimental data demonstrate that spontaneous or induced abortions do not significantly alter the risk of breast cancer. In this study, we briefly discuss the different types and stages of breast cancer, various risk factors, and potential mechanisms involved in early full-term pregnancy-induced protection against breast cancer. Understanding how early full-term pregnancy induces protection against breast cancer will help design innovative preventive and therapeutic strategies. This understanding can also help in the development of molecular biomarkers that can be of tremendous help in predicting the risk of breast cancer in the general population.

An Embryonic and Induced Pluripotent Stem Cell Model for Ovarian Granulosa Cell Development and Steroidogenesis

Embryoid bodies (EBs) can serve as a system for evaluating pluripotency, cellular differentiation, and tissue morphogenesis. In this study, we use EBs derived from mouse embryonic stem cells (mESCs) and human amniocyte-derived induced pluripotent stem cells (hAdiPSCs) as a model for ovarian granulosa cell (GC) development and steroidogenic cell commitment. We demonstrated that spontaneously differentiated murine EBs (mEBs) and human EBs (hEBs) displayed ovarian GC markers, such as aromatase (CYP19A1), FOXL2, AMHR2, FSHR, and GJA1. Comparative microarray analysis identified both shared and unique gene expression between mEBs and the maturing mouse ovary. Gene sets related to gonadogenesis, lipid metabolism, and ovarian development were significantly overrepresented in EBs. Of the 29 genes, 15 that were differentially regulated in steroidogenic mEBs displayed temporal expression changes between embryonic, postnatal, and mature ovarian tissues by polymerase chain reaction. Importantly, both mEBs and hEBs were capable of gonadotropin-responsive estradiol (E2) synthesis in vitro (217-759 pg/mL). Live fluorescence-activated cell sorting-sorted AMHR2⁺ granulosa-like cells from mEBs continued to produce E2 after purification (15.3 pg/mL) and secreted significantly more E2 than AMHR2^- cells (8.6 pg/mL, P < .05). We conclude that spontaneously differentiated EBs of both mESC and hAdiPSC origin can serve as a biologically relevant model for ovarian GC differentiation and steroidogenic cell commitment. These cells should be further investigated for therapeutic uses, such as stem cell-based hormone replacement therapy and in vitro maturation of oocytes.

Dietary Natural Products for Prevention and Treatment of Breast Cancer

Breast cancer is the most common cancer among females worldwide. Several epidemiological studies suggested the inverse correlation between the intake of vegetables and fruits and the incidence of breast cancer. Substantial experimental studies indicated that many dietary natural products could affect the development and progression of breast cancer, such as soy, pomegranate, mangosteen, citrus fruits, apple, grape, mango, cruciferous vegetables, ginger, garlic, black cumin, edible macro-fungi, and cereals. Their anti-breast cancer effects involve various mechanisms of action, such as downregulating ER-α expression and activity, inhibiting proliferation, migration, metastasis and angiogenesis of breast tumor cells, inducing apoptosis and cell cycle arrest, and sensitizing breast tumor cells to radiotherapy and chemotherapy. This review summarizes the potential role of dietary natural products and their major bioactive components in prevention and treatment of breast cancer, and special attention was paid to the mechanisms of action.

Radiation-associated breast cancer and gonadal hormone exposure: a report from the Childhood Cancer Survivor Study

BACKGROUND

The relationship between hormone exposure and breast cancer risk in women treated with chest radiotherapy for childhood cancer is uncertain.

METHODS

Participants included 1108 females from the Childhood Cancer Survivor Study who were diagnosed with childhood cancer 1970-1986, treated with chest radiotherapy, and survived to ages ⩾20 years. Hazard ratios (HRs) and 95% confidence intervals (CIs) from Cox models adjusted for chest radiation field, delivered dose, anthracycline exposure, and age at childhood cancer estimated risk.

RESULTS

Among 195 women diagnosed with breast cancer, 102 tumours were oestrogen-receptor positive (ER+). Breast cancer risk increased with ⩾10 years of ovarian function after chest radiotherapy vs <10 years (HR=2.89, CI 1.56-5.53) and for radiotherapy given within 1 year of menarche vs >1 year from menarche (HR=1.80, CI 1.19-2.72). Risk decreased with decreasing age at menopause (P_trend=0.014). Risk factors did not differ for ER+ breast cancer. Survivors with an age at menopause <20 years treated with hormone therapy had a lower breast cancer risk than premenopausal survivors (HR=0.47, CI 0.23-0.94).

CONCLUSIONS

Endogenous hormones are key contributors to breast cancer observed among childhood cancer survivors. Hormone therapy given for premature ovarian insufficiency does not fully replace the function that endogenous hormones have in breast cancer development.

Feruloyl dopamine-O-hexosides are efficient marker compounds as orthogonal validation for authentication of black cohosh (Actaea racemosa)-an UHPLC-HRAM-MS chemometrics study

Due to the complexity and variation of the chemical constituents in authentic black cohosh (Actaea racemosa) and its potential adulterant species, an accurate and feasible method for black cohosh authentication is not easy. A high-resolution accurate mass (HRAM) LC-MS fingerprinting method combined with chemometric approach was employed to discover new marker compounds. Seven hydroxycinnamic acid amide (HCAA) glycosides are proposed as potential marker compounds for differentiation of black cohosh from related species, including two Asian species (A. foetida, A. dahurica) and two American species (A. pachypoda, A. podocarpa). These markers were putatively identified by comparing their mass spectral fragmentation behavior with those of their authentic aglycone compounds and phytochemistry reports. Two isomers of feruloyl methyldopamine 4-O-hexoside ([M + H]⁺ 506) and one feruloyl tyramine 4-O-hexoside ([M + H]⁺ 476) contributed significantly to the separation of Asian species in principle component analysis (PCA) score plot. The efficacy of the models built on four reasonable combinations of these markers in differentiating black cohosh and its adulterants were evaluated and validated by partial least-square discriminant analysis (PLS-DA). Two models based on these reduced dataset achieved 100% accuracy based on the current sample collection, including the model that used only three feruloyl dopamine-O-hexoside isomers ([M + H]⁺ 492) and one feruloyl dopamine-O-dihexoside ([M + H-hexosyl]⁺ at m/z 492). Graphical abstract Hydroxycinnamic acid amide glycosides are proposed as potential marker compounds for authentication of black cohosh.

Hormone therapy for ovarian cancer survivors: systematic review and meta-analysis

OBJECTIVE

Hormone therapy (HT) alleviates menopausal symptoms, but there is a lack of consensus regarding its use among premenopausal ovarian cancer survivors.

METHODS

We systematically reviewed the literature and searched the Medline (1966-2014), Scopus (2004-2014), Popline (1974-2014), ClinicalTrials.gov (2008-2014), and Cochrane Central Register of Controlled Trials CENTRAL (1999-2014) databases and the reference lists of electronically retrieved studies. Statistical meta-analysis was performed using RevMan 5.1 software.

RESULTS

Six studies were included in our systematic review, which involved 1,521 women. Among them, 451 women (29.6%) received HT, whereas the remaining 1,070 women (70.4%) did not receive any treatment. We noticed a statistically significant reduction of ovarian cancer-related deaths among women who received HT (odds ratio, 0.47; 95% CI, 0.28-0.80); however, disease recurrence rates did not differ between the two groups (odds ratio, 0.71; 95% CI, 0.45-1.14). Studies included in the present systematic review did not report a significant difference in overall survival and disease-free survival rates among women receiving HT and controls.

CONCLUSIONS

Based on the results of meta-analysis, HT does not influence the odds of ovarian cancer recurrence; however, this conclusion must be confirmed separately because of significant limitations in the methodological quality of the studies included.

Population Attributable and Preventable Fractions: Cancer Risk Factor Surveillance, and Cancer Policy Projection

The proportions of new cancer cases and deaths that are caused by exposure to risk factors and that could be prevented are key statistics for public health policy and planning. This paper summarizes the methodologies for estimating, challenges in the analysis of, and utility of, population attributable and preventable fractions for cancers caused by major risk factors such as tobacco smoking, dietary factors, high body fat, physical inactivity, alcohol consumption, infectious agents, occupational exposure, air pollution, sun exposure, and insufficient breastfeeding. For population attributable and preventable fractions, evidence of a causal relationship between a risk factor and cancer, outcome (such as incidence and mortality), exposure distribution, relative risk, theoretical-minimum-risk, and counterfactual scenarios need to be clearly defined and congruent. Despite limitations of the methodology and the data used for estimations, the population attributable and preventable fractions are a useful tool for public health policy and planning.

RANK as a therapeutic target in cancer

The RANK signaling pathway has emerged as a new target in breast cancer as receptor activator of nuclear factor κB ligand (RANKL) and its receptor RANK mediate the pro-tumorigenic role of progesterone in the mammary gland. Thousands of cancer patients worldwide are already taking RANKL inhibitors for the management of bone metastasis, given the relevance of this pathway in osteoclastogenesis and bone resorption. RANK signaling also has multiple divergent effects in immunity and inflammation, both in the generation of active immune responses and in the induction of tolerance: it is required for lymph node organogenesis, thymic medullary epithelial development and self-tolerance, and regulates activation of several immune cells and inflammatory processes. The RANK pathway interferes with mammary epithelial differentiation and mediates the major proliferative response of mammary epithelium to progesterone and progesterone-driven expansion of mammary stem cells; it also controls hair follicle and epidermal stem cell homeostasis, pointing to RANK as a key regulator of epithelial stemness. Here we revisit the main functions of RANK signaling in bone remodeling, immune cells and epithelial differentiation. We also discuss the mechanistic evidence that supports its pleiotropic effects on cancer: from bone metastasis to immune and cancer-cell-dependent effects.