Endocrine therapy for breast cancer in the primary care setting

Influence of tumor microenvironment on the different breast cancer subtypes and applied therapies

Despite the significant improvements made in breast cancer therapy during the last decades, this disease still has increasing incidence and mortality rates. Different targets involved in general processes, like cell proliferation and survival, have become alternative therapeutic options for this disease, with some of them already used in clinic, like the CDK4/6 inhibitors for luminal A tumors treatment. Nevertheless, there is a demand for novel therapeutic strategies focused not only on tumor cells, but also on their microenvironment. Tumor microenvironment (TME) is a very complex and dynamic system that, more than surrounding and supporting tumor cells, actively participates in tumor development and progression. During the last decades, it has become clear that the cellular and acellular components of TME differ between the various breast cancer subtypes and shape the differences regarding their severity and prognosis. The pivotal role of the TME in controlling tumor growth and influencing responses to therapy represents a potential source for novel targets and therapeutic strategies. In this review, we present a description of the multiple therapeutic options used for different breast cancer subtypes, as well as the influence that the TME may exert on the development of the disease and on the response to the distinct therapies, which in some cases may explain their failure by the occurrence of relapses and resistance. Furthermore, the ongoing studies focused on the use of TME components for developing potential cancer treatments are described.

Feasibility of implementing acupuncture in medically underserved breast cancer survivors (FAB): A protocol

Nearly 94% of breast cancer survivors experience one or more symptoms or side effects during or after endocrine therapy. Joint pain, hot flashes, sleep disturbance, fatigue, depression, and anxiety are the most common concurrent symptoms, some of which can persist for 5 to 10 years. Acupuncture is a holistic modality that addresses multiple symptoms and side effects in a single therapy. Acupuncture has not yet been investigated for its effectiveness in treating the multiple symptoms experienced by breast cancer survivors receiving endocrine therapy. Medically underserved breast cancer survivors typically have limited access to acupuncture. The barriers limiting access to acupuncture need to be removed to enable equal access to breast cancer survivors for this evidence-based treatment. Thus, we developed a randomized controlled trial with a 5-week acupuncture intervention versus usual care for medically underserved breast cancer survivors. Mixed methods (semi-structured interviews, surveys, study notes) will be used to obtain in-depth understanding of barriers and facilitators for eventual implementation of the acupuncture intervention. This study will facilitate the widespread implementation, dissemination, and sustained utilization of acupuncture for symptom management among medically underserved breast cancer survivors receiving endocrine therapy.

Tailoring Potential Natural Compounds for the Treatment of Luminal Breast Cancer

Breast cancer (BC) is the most diagnosed cancer worldwide, mainly affecting the epithelial cells from the mammary glands. When it expresses the estrogen receptor (ER), the tumor is called luminal BC, which is eligible for endocrine therapy with hormone signaling blockade. Hormone therapy is essential for the survival of patients, but therapeutic resistance has been shown to be worrying, significantly compromising the prognosis. In this context, the need to explore new compounds emerges, especially compounds of plant origin, since they are biologically active and particularly promising. Natural products are being continuously screened for treating cancer due to their chemical diversity, reduced toxicity, lower side effects, and low price. This review summarizes natural compounds for the treatment of luminal BC, emphasizing the activities of these compounds in ER-positive cells. Moreover, their potential as an alternative to endocrine resistance is explored, opening new opportunities for the design of optimized therapies.

Breast Tumor Cells Evade the Cytotoxic Action of Anastrozole, Aspirin, and Clopidogrel Cocktail

Globally, breast cancer is among the most frequently diagnosed and common cause of death among women. Aromatase inhibitors, such as anastrozole, are one of the first-line therapies used in the treatment of breast cancer in postmenopausal women; however, thromboembolic complications are common. Thus, this study investigated the combined effects of anastrozole and antiplatelet therapies, aspirin and clopidogrel, on breast cancer cytotoxicity and survival in vitro. Breast cancer cell lines (MCF-7 and T47D) were treated with varying Cmax concentrations of anastrozole and/or antiplatelet therapies for 24 h. A wound-healing scratch assay was used to measure migration and the WST-1 assay for cellular proliferation. An autophagy/cytotoxicity dual staining kit was used to assay cell death and survival. Changes in cell morphology were assessed using scanning electron microscopy. Data were analyzed with Statistica software. Our findings showed that sub-phenotypic differences exist between the luminal-A breast cancer cell lines, with T47D cells being more aggressive than MCF-7 cells. Cellular proliferation and migration responded in a dose-dependent manner for the different treatment groups. Notably, anastrozole combined with aspirin and clopidogrel mediated higher levels of cell survival than each agent individually, with autophagy levels being significantly increased in comparison to that induced with antiplatelet therapy alone.

Understanding and targeting resistance mechanisms in cancer

Resistance to cancer therapies has been a commonly observed phenomenon in clinical practice, which is one of the major causes of treatment failure and poor patient survival. The reduced responsiveness of cancer cells is a multifaceted phenomenon that can arise from genetic, epigenetic, and microenvironmental factors. Various mechanisms have been discovered and extensively studied, including drug inactivation, reduced intracellular drug accumulation by reduced uptake or increased efflux, drug target alteration, activation of compensatory pathways for cell survival, regulation of DNA repair and cell death, tumor plasticity, and the regulation from tumor microenvironments (TMEs). To overcome cancer resistance, a variety of strategies have been proposed, which are designed to enhance the effectiveness of cancer treatment or reduce drug resistance. These include identifying biomarkers that can predict drug response and resistance, identifying new targets, developing new targeted drugs, combination therapies targeting multiple signaling pathways, and modulating the TME. The present article focuses on the different mechanisms of drug resistance in cancer and the corresponding tackling approaches with recent updates. Perspectives on polytherapy targeting multiple resistance mechanisms, novel nanoparticle delivery systems, and advanced drug design tools for overcoming resistance are also reviewed.

Cannabidiol as a Promising Adjuvant Therapy for Estrogen Receptor-Positive Breast Tumors: Unveiling Its Benefits with Aromatase Inhibitors

BACKGROUND

Estrogen receptor-positive (ER⁺) breast cancer is the most diagnosed subtype, with aromatase inhibitors (AIs) being one of the therapeutic drug types used in the clinic. However, endocrine resistance may develop after prolonged treatment, and different approaches, such as combining endocrine and targeted therapies, have been applied. Recently, we demonstrated that cannabidiol (CBD) induces anti-tumor actions in ER⁺ breast cancer cells by targeting aromatase and ERs. Considering this, we studied, in vitro, whether CBD when combined with AIs could improve their effectiveness.

METHODS

MCF-7aro cells were used and the effects on cell viability and on the modulation of specific targets were investigated.

RESULTS

CBD when combined with anastrozole (Ana) and letrozole (Let) caused no beneficial effect in comparison to the isolated AIs. In contrast, when combined with the AI exemestane (Exe), CBD potentiated its pro-cell death effects, abolished its estrogen-like effect, impaired ERα activation, and prevented its oncogenic role on the androgen receptor (AR). Moreover, this combination inhibited ERK_1/2 activation, promoting apoptosis. The study of the hormonal microenvironment suggests that this combination should not be applied in early stages of ER⁺ breast tumors.

CONCLUSIONS

Contrary to Ana and Let, this study highlights the potential benefits of combining CBD with Exe to improve breast cancer treatment and opens up the possibility of new therapeutic approaches comprising the use of cannabinoids.

Adherence to Adjuvant Endocrine Therapy in Breast Cancer Patients

BACKGROUND

Adjuvant endocrine therapy (AET) reduces breast cancer recurrence and mortality of women with hormone-receptor-positive tumors, but poor adherence remains a significant problem. The aim of this study was to analyze AET side effects and their impact on adherence to treatment.

METHODS

A total of 373 breast cancer patients treated with AET filled out a specific questionnaire during their follow up visits at the Breast Unit of our Centre.

RESULTS

Side effects were reported by 81% of patients, 84% of those taking tamoxifen and 80% of those taking aromatase inhibitors (AIs). The most common side effect in the tamoxifen group was hot flashes (55.6%), while in the AI group it was arthralgia (60.6%). The addition of GnRH agonists to both tamoxifen and AI significantly worsened all menopausal symptoms. Overall, 12% of patients definitively discontinued AET due to side effects, 6.4% during the first 5 years and 24% during extended therapy. Patients who had previously received chemotherapy or radiotherapy reported a significantly lower discontinuation rate.

CONCLUSIONS

AET side effects represent a significant problem in breast cancer survivors leading to irregular assumption and discontinuation of therapy. Adherence to AET may be improved by trustful patient-physician communication and a good-quality care network.

An Exemestane Derivative, Oxymestane-D1, as a New Multi-Target Steroidal Aromatase Inhibitor for Estrogen Receptor-Positive (ER+) Breast Cancer: Effects on Sensitive and Resistant Cell Lines

Around 70-85% of all breast cancer (BC) cases are estrogen receptor-positive (ER⁺). The third generation of aromatase inhibitors (AIs) is the first-line treatment option for these tumors. Despite their therapeutic success, they induce several side effects and resistance, which limits their efficacy. Thus, it is crucial to search for novel, safe and more effective anti-cancer molecules. Currently, multi-target drugs are emerging, as they present higher efficacy and lower toxicity in comparison to standard options. Considering this, this work aimed to investigate the anti-cancer properties and the multi-target potential of the compound 1α,2α-epoxy-6-methylenandrost-4-ene-3,17-dione (Oxy), also designated by Oxymestane-D1, a derivative of Exemestane, which we previously synthesized and demonstrated to be a potent AI. For this purpose, it was studied for its effects on the ER⁺ BC cell line that overexpresses aromatase, MCF-7aro cells, as well as on the AIs-resistant BC cell line, LTEDaro cells. Oxy reduces cell viability, impairs DNA synthesis and induces apoptosis in MCF-7aro cells. Moreover, its growth-inhibitory properties are inhibited in the presence of ERα, ERβ and AR antagonists, suggesting a mechanism of action dependent on these receptors. In fact, Oxy decreased ERα expression and activation and induced AR overexpression with a pro-death effect. Complementary transactivation assays demonstrated that Oxy presents ER antagonist and AR agonist activities. In addition, Oxy also decreased the viability and caused apoptosis of LTEDaro cells. Therefore, this work highlights the discovery of a new and promising multi-target drug that, besides acting as an AI, appears to also act as an ERα antagonist and AR agonist. Thus, the multi-target action of Oxy may be a therapeutic advantage over the three AIs applied in clinic. Furthermore, this new multi-target compound has the ability to sensitize the AI-resistant BC cells, which represents another advantage over the endocrine therapy used in the clinic, since resistance is a major drawback in the clinic.

Marker assessments in ER-positive breast cancers: old markers, new applications?

Evaluation of oestrogen receptor (ER) expression by immunostaining is essential in the pathological assessment of breast cancer. Its expression is intercorrelated with clinicopathological features, molecular typing, and treatment selection. The development of novel therapeutic agents related to ER status, the recent ASCO introduction of an ER-low positive category of breast cancers, and the ever-increasing plethora of diagnostic and theragnostic markers call for a timely update. In this article we aim to review the clinicopathological features of ER-positive breast cancers, with an emphasis on ER-low positive breast cancers, and a focus on updating the (i) assessment, reporting and interpretation of ER immunohistochemical (IHC) staining, (ii) correlations of ER status with other diagnostic and theragnostic markers, and (iii) implications for treatment selection and response. In the face of the developments in IHC and molecular techniques and targeted therapy, ER immunostaining is still expected to remain as the core component of prognostic and theragnostic assessment of breast cancers.

Effects of Endocrine Therapy on Cardiovascular Diseases and Type 2 Diabetes Among Breast Cancer Survivors: The National Health Insurance Service Database of Korea

Background Although endocrine therapy is an effective treatment for breast cancer, its antiestrogen effects are associated with increased risks of cardiovascular diseases and type 2 diabetes. This study aimed to investigate the association between endocrine therapy and the risk of cardiovascular diseases and type 2 diabetes among breast cancer survivors in Korea, in consideration of various age groups. Methods and Results In the National Health Insurance Service database of Korea, a total of 133 171 patients with breast cancer aged ≥20 years were included in the current study. Endocrine therapy was treated as time-varying exposure, and patients were categorized as nonusers, selective estrogen receptor modulator users, aromatase inhibitor users, and both users. Time-dependent Cox regression models were used to estimate hazard ratios (HRs) and 95% CIs. Age at diagnosis, socioeconomic status, histological type, other treatments, and comorbidities were adjusted in the model. Compared with nonusers, selective estrogen receptor modulator users were associated with higher risks of stroke (HR, 1.20 [95% CI, 1.04-1.40]) and venous thromboembolism (HR, 1.47 [95% CI, 1.13-1.90]), whereas aromatase inhibitor users were associated with a higher risk of coronary heart disease (HR, 1.22 [95% CI, 1.06-1.41]). The risk of type 2 diabetes was associated with selective estrogen receptor modulator users (HR, 1.13 [95% CI, 1.05-1.21]), aromatase inhibitor users (HR, 1.14 [95% CI, 1.05-1.23]), and both users (HR, 1.24 [95% CI, 1.10-1.39]). In particular, the risk of a composite of cardiovascular diseases was higher in younger or premenopausal patients. Conclusions In breast cancer survivors in Korea, endocrine therapy is associated with a higher risk of cardiovascular diseases and type 2 diabetes. Monitoring of cancer comorbidities after endocrine therapy is needed in younger and older patients.

Design and Evaluation of pH Sensitive PEG-Protamine Nanocomplex of Doxorubicin for Treatment of Breast Cancer

Cancer is the most common cause of mortality worldwide. There is dire need of modern strategies—such as surface modification of nanocarriers—to combat this global illness. Incorporation of active targeting ligands has arisen as a novel platform for specific tumor targeting. The aim of the current study was to formulate PEG-protamine complex (PPC) of doxorubicin (DOX) for treatment of breast cancer (BC). DOX coupling with PEG can enhance cell-penetrating ability: combating resistance in MDA-MB 231 breast cancer cells. Ionic gelation method was adopted to fabricate a pH sensitive nanocomplex. The optimized nanoformulation was characterized for its particle diameter, zeta potential, surface morphology, entrapment efficiency, crystallinity, and molecular interaction. In vitro assay was executed to gauge the release potential of nanoformulation. The mean particle size, zeta potential, and polydispersity index (PDI) of the optimized nanoparticles were observed to be 212 nm, 15.2 mV, and 0.264, respectively. Crystallinity studies and Fourier transform infrared (FTIR) analysis revealed no molecular interaction and confirmed the amorphous nature of drug within nanoparticles. The in vitro release data indicate sustained drug release at pH 4.8, which is intracellular pH of breast cancer cells, as compared to the drug solution. PPC loaded with doxorubicin can be utilized as an alternative and effective approach for specific targeting of breast cancer.

The relationship among psychosocial adaptation, medication adherence and quality of life in breast cancer women with adjuvant endocrine therapy

BACKGROUND

Patients undergoing endocrine therapy for breast cancer often suffer from poor psychosocial adaptation, low compliance with endocrine therapy and poor quality of life. However, the relationship among the three is not completely clear. The aims of this study were to investigate the status of psychosocial adaptation (PSA), medication adherence and quality of life (QOL) in breast cancer women with adjuvant endocrine therapy (AET), and to analyze the influencing factors of QOL and explore the relationship among them.

METHODS

346 breast cancer women were selected who underwent endocrine therapy after surgery, and data collected by the general information questionnaire, the PSA questionnaire among breast cancer women with AET, Morisky Medication Adherence Scale and The Functional Assessment of Cancer Therapy-Breast (FACT-B). The relationship among the variables was investigated by univariate analysis, multiple stepwise regression analysis and mediating effect analysis.

RESULTS

The scores of PSA, medication adherence and QOL were slightly above the medium level. Univariate analysis showed that there were significant differences in QOL among breast cancer women of AET with different types of exercise, medical payment methods, discomfort symptoms (headache, hypomnesis, arthralgia, perturbation), type of discomfort symptoms, medication adherence and PSA; Multi-factor analysis showed that PSA and medication adherence were the influential factors of QOL; mediating effect showed that medication adherence played a partial mediating role in PSA and QOL.

CONCLUSION

The QOL of breast cancer women with AET will be directly affected by PSA. Medication compliance has a weak mediating effect in the indirect impact of PSA on the QOL. In the future, clinical nursing work should take targeted measures to improve the PSA level of patients, and effectively improve the compliance of patients with medication, so as to better improve the QOL of breast cancer women.

Gynecologic Symptoms among Hormone Receptor-Positive Breast Cancer Patients on Oral Endocrine Therapy: A Cross-Sectional Study

Endocrine therapy (ET) for hormone receptor-positive (HR+) breast cancer can contribute to gynecologic symptoms (GS) that impact vaginal health, sexual function, and quality of life (QoL). A cross-sectional study was conducted at St. Michael’s Hospital in Toronto, Canada between July 2017 and June 2018 to examine the occurrence and frequency of GS among HR+ breast cancer patients on ET, patient-provider communication, female sexual dysfunction (FSD), and QoL. A Treatment Experience questionnaire was developed for this study and the Female Sexual Function Index (FSFI) and Menopause-Specific Quality of Life questionnaire (MENQOL) were also administered. Of 151 patients surveyed, 77 (51.0%) were on tamoxifen and 74 (49.0%) on an aromatase inhibitor. Most patients (84.1%, 95% confidence interval [CI] 77.3% to 89.5%) experienced at least one GS “all the time” or “often”, or one or more infections, in the past year. Only 44 (31.9%) patients reported that their oncologist had ever previously asked them about experiencing GS. The prevalence of FSD was 61.2% (95% CI 46.2% to 74.8%) among 49 sexually active patients that completed the FSFI. Symptoms captured in the MENQOL’s vasomotor domain were deemed most bothersome. Side effect management and patient-provider communication should be prioritized to optimize GS, vaginal health, and sexual function of ET users.

Towards Unravelling the Role of ERα-Targeting miRNAs in the Exosome-Mediated Transferring of the Hormone Resistance

Hormone therapy is one of the most effective breast cancer treatments, however, its application is limited by the progression of hormonal resistance, both primary or acquired. The development of hormonal resistance is caused either by an irreversible block of hormonal signalling (suppression of the activity or synthesis of hormone receptors), or by activation of oestrogen-independent signalling pathways. Recently the effect of exosome-mediated intercellular transfer of hormonal resistance was revealed, however, the molecular mechanism of this effect is still unknown. Here, the role of exosomal miRNAs (microRNAs) in the transferring of hormonal resistance in breast cancer cells has been studied. The methods used in the work include extraction, purification and RNAseq of miRNAs, transfection of miRNA mimetics, immunoblotting, reporter analysis and the MTT test. Using MCF7 breast cancer cells and MCF7/T tamoxifen-resistant sub-line, we have found that some miRNAs, suppressors of oestrogen receptor signalling, are overexpressed in the exosomes of the resistant breast cancer cells. The multiple (but not single) transfection of one of the identified miRNA, miR-181a-2, into oestrogen-dependent MCF7 cells induced the irreversible tamoxifen resistance associated with the continuous block of the oestrogen receptor signalling and the activation of PI3K/Akt pathway. We suppose that the miRNAs-ERα suppressors may act as trigger agents inducing the block of oestrogen receptor signalling and breast cancer cell transition to an aggressive oestrogen-independent state.

Effects of the Better Model Based Counseling on Sexuality of Women with Breast Cancer

Purpose

Breast cancer and side effects of its treatment cause many problems such as body image, impaired quality of life, and sexual dysfunction. The aim of this experimental study is to determine the effect of BETTER Model-based counseling programme on sexual problems of female patients with breast cancer.

Methods

This study was conducted with experimental and control group design. The data of the study were obtained between April 2016 and March 2018. The sample group consisted of 60 women who agreed to participate in the study. Information Form, "EORTC Quality of Life Questionnaire-BR23", "Female Sexual Function Index", and "Body Cathexis Scale" were used in order to collect the data. The "Better Model"-based counseling programme was applied in four sessions a week in the experimental group. The scales were applied again one month after the last session. The women in the control group were subjected to routine hospital control after the scales were applied. The scales were applied again in this group one month later.

Results

After the "Better Model"-based counseling programme was applied,the women in the experimental group had higher scores from lubrication, orgasm, and pain subscales, and overall female sexual function index. Besides, the women in the experimental group had higher scores from body image subscale of functional scale of the quality of life questionnaire.

Conclusions

In the study, it was detected that the "Better Model"-based counseling was effective in raising and enhancing sexual health awareness and decreasing the existing sexual issues in women with breast cancer.

Network Pharmacology-Based Dissection of the Comprehensive Molecular Mechanisms of the Herbal Prescription FDY003 Against Estrogen Receptor-Positive Breast Cancer

Estrogen receptor-positive breast cancer (ERPBC) is the commonest subtype of breast cancer, with a high prevalence, incidence, and mortality. Herbal drugs are increasingly being used to treat ERPBC, although their mechanisms of action are not fully understood. Therefore, in this study, we aimed to analyze the therapeutic properties of FDY003, a herbal anti-ERPBC prescription, using a network pharmacology approach. FDY003 decreased the viability of human ERPBC cells and sensitized them to tamoxifen, an endocrine drug that is widely used in the treatment of ERPBC. The network pharmacology analysis revealed 18 pharmacologically active components in FDY003 that may interact with and regulate 66 therapeutic targets. The enriched gene ontology terms for the FDY003 targets were associated with the modulation of cell survival and death, cell proliferation and growth arrest, and estrogen-associated cellular processes. Analysis of the pathway enrichment of the targets showed that FDY003 may target a variety of ERPBC-associated pathways, including the PIK3-Akt, focal adhesion, MAPK, and estrogen pathways. Overall, these data provide a comprehensive mechanistic insight into the anti-ERPBC activity of FDY003.

The anti-cancer potential of crotoxin in estrogen receptor-positive breast cancer: Its effects and mechanism of action

Estrogen receptor-positive (ER⁺) breast cancer is the most diagnosed subtype of breast cancer. Currently, aromatase inhibitors (AIs) are used as first-line treatment option in this type of tumors, however they cause several side effects, which is why new therapeutic approaches are demanding. The South American rattlesnake Crotalus durissus terrificus produces a venom enriched in several bioactive substances, like phospholipases A₂ (PLA₂). One of those is crotoxin, a β-neurotoxin, that has already been reported for its anti-cancer properties in different cancers. Recently, its clinical interest has emerged and, in fact, a clinical trial in patients with advanced cancer is underway. Considering this, in this work, we studied the biological mechanisms behind the anti-cancer effects of crotoxin B (CTX) in an ER⁺ aromatase-overexpressing breast cancer cell line (MCF-7aro cells). Results revealed that CTX impairs MCF-7aro cells growth, through a cell cycle arrest at G₂/M phase, inhibition of ERK1/2 pathway and by apoptosis through activation of caspase-8. In addition, it can be considered a safe natural compound as did not affect non-cancerous cells and only showed anti-growth effects in breast cancer cells. Therefore, this study represents an important landmark to better understand the effects and mechanisms of action of crotoxin in ER⁺ breast cancer.

Analyses of the association between breast cancer and osteoporosis/fracture history: a cross-sectional study using KoGES HEXA data

We performed a nationwide, population-based cohort study to evaluate the risk of osteoporosis and osteoporotic fracture in patients with breast cancer using the data from Korean Genome and Epidemiology Study (KoGES) and concluded that Korean women with breast cancer had a higher risk of osteoporosis than healthy women, regardless of age.

PURPOSE

This study aimed to evaluate the association between breast cancer and the occurrence of osteoporosis and osteoporotic fracture using data from the Korean Genome and Epidemiology Study (KoGES).

METHODS

Using the national KoGES health examinee (HEXA) data consisting of data from urban resident participants ≥ 40 years old, we extracted data for patients with breast cancer (n = 1080) and for control participants (n = 106,993); we then analyzed the occurrence of osteoporosis and osteoporotic fracture at baseline from 2004 to 2013 and during follow-up from 2012 to 2016. A logistic regression model was used to analyze the odds ratios (ORs) and the 95% confidence intervals (CIs). Subgroup analysis was performed based on age (younger group aged ≤ 51 years old; older group aged ≥ 52 years old).

RESULTS

The ORs (95% CIs) for osteoporosis and osteoporotic fracture were 1.54 (95% CI = 1.28-1.84, P < 0.001) and 1.01 (95% CI = 0.82-1.23, P = 0.949), respectively, in the breast cancer group. In the subgroup analysis based on age, the ORs (95% CIs) for osteoporosis were 2.41 (95% CI = 1.70-3.43, P < 0.001) in the younger group and 1.33 (95% CI = 1.08-1.64, P = 0.007) in the older group of breast cancer patients. The ORs (95% CIs) for osteoporotic fracture were 1.15 (95% CI = 0.81-1.63, P = 0.441) in the younger group and 0.95 (95% CI = 0.74-1.21, P = 0.661) in the older group of breast cancer patients.

CONCLUSION

We concluded that Korean women with breast cancer had a higher risk of osteoporosis than healthy women, but the same finding was not observed for osteoporotic fracture, regardless of age.

Discovery of a multi-target compound for estrogen receptor-positive (ER+) breast cancer: Involvement of aromatase and ERs

Despite intense research, breast cancer remains the leading cause of cancer-related death in women worldwide, being estrogen receptor-positive (ER⁺) the most common subtype. Nowadays, aromatase inhibitors (AIs), the selective estrogen receptor modulator (SERM) tamoxifen and the selective estrogen receptor down-regulator (SERD) fulvestrant are used as therapeutic options for ER⁺ breast cancer, since they interfere directly with the production of estrogens and with the activation of estrogen-dependent signaling pathways. Despite the success of these treatments, the occurrence of resistance limits their clinical efficacy, demanding the development of novel therapies. Recently, multi-target compounds emerged as promising therapeutic strategies for ER⁺ breast cancer, as they can potentially modulate several important targets simultaneously. In line with this, in this work, the anti-cancer properties and multi-target action of 1,1-Bis(4-hydroxyphenyl)-2-phenylbut-1-ene, tamoxifen bisphenol (1,1-BHPE), were evaluated in an ER⁺ breast cancer cell model (MCF-7aro cells). Molecular docking analysis predicted that 1,1-BHPE was able to bind to aromatase, ERα and ERβ. In vitro studies showed that, although it did not present anti-aromatase activity, 1,1-BHPE reduced aromatase protein levels and interfered with ERα and ERβ signaling pathways, acting as an ERα antagonist and inducing ERβ up-regulation. Through these mechanisms, 1,1-BHPE was able to impair breast cancer growth and induce apoptosis. This represents an important therapeutic advantage because the main players responsible for estrogen production and signaling are modulated by a single compound. To the best of our knowledge, this is the first study describing the anti-cancer properties of 1,1-BHPE as a multi-target compound specific for ER⁺ breast cancer.

How patients experience endocrine therapy for breast cancer: an online survey of side effects, adherence, and medical team support

PURPOSE

Many patients with hormone receptor-positive (HR+) breast cancer do not adhere to endocrine therapy (ET), and treatment-related side effects are often discussed by participants in online breast cancer forums. Our aim was to survey this unique group of patients about their ET-related experiences.

METHODS

We partnered with patients active in breast cancer social media communities to develop a survey assessing ET-related side effects and medical team communication. Patients with a history of HR+ breast cancer who had received a recommendation to take ET were eligible to participate in the anonymous, online survey.

RESULTS

Respondents included 2353 women and 54 men. Aromatase inhibitors were the most commonly used medication. Side effects were reported by 91.2%, were more often experienced by women than men (p < 0.001), and were primarily related to medication type. Approximately one-third of respondents discontinued therapy early. While most felt supported by their medical team, 31.5% reported that their side effects were dismissed or minimized. Survey respondents most frequently reported that a healthy diet and exercise, yoga/acupuncture, and vitamins/supplements were helpful in managing ET-related side effects.

CONCLUSIONS

ET-related side effects are very common, and one-third discontinued treatment early. Lifestyle changes and complementary therapies can be important tools for side effect management. One-third of patients did not feel that their side effects were taken seriously.

IMPLICATIONS FOR CANCER SURVIVORS

This is the largest survey of ET use by participants in online breast cancer communities. Further research is needed to identify strategies to improve treatment adherence and to better manage ET-related side effects.

Synthesis of 1,4-Biphenyl-triazole Derivatives as Possible 17β-HSD1 Inhibitors: An in Silico Study

Triazoles occupy an important position in medicinal chemistry because of their various biological activities. The structural features of 1,2,3-triazoles enable them to act as a bioisostere of different functional groups such as amide, ester, carboxylic acid, and heterocycle, being capable of forming hydrogen bonds and π-π interactions or coordinate metal ions with biological targets. In this work, the synthesis of 1,2,3-triazole derivatives via copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is reported. Overexpression of 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1) is often found in breast cancer cells. Molecular similarity and docking analysis were used to evaluate the potential inhibitory activity of 1,2,3-triazoles synthesized over 17β-HSD1 for the treatment of mammary tumors. Our in silico analysis shows that compounds 4c, 4d, 4f, 4g, and 4j are good molecular scaffold candidates as 17β-HSD1 inhibitors.

Computer-Aided Ligand Discovery for Estrogen Receptor Alpha

Breast cancer (BCa) is one of the most predominantly diagnosed cancers in women. Notably, 70% of BCa diagnoses are Estrogen Receptor α positive (ERα+) making it a critical therapeutic target. With that, the two subtypes of ER, ERα and ERβ, have contrasting effects on BCa cells. While ERα promotes cancerous activities, ERβ isoform exhibits inhibitory effects on the same. ER-directed small molecule drug discovery for BCa has provided the FDA approved drugs tamoxifen, toremifene, raloxifene and fulvestrant that all bind to the estrogen binding site of the receptor. These ER-directed inhibitors are non-selective in nature and may eventually induce resistance in BCa cells as well as increase the risk of endometrial cancer development. Thus, there is an urgent need to develop novel drugs with alternative ERα targeting mechanisms that can overcome the limitations of conventional anti-ERα therapies. Several functional sites on ERα, such as Activation Function-2 (AF2), DNA binding domain (DBD), and F-domain, have been recently considered as potential targets in the context of drug research and discovery. In this review, we summarize methods of computer-aided drug design (CADD) that have been employed to analyze and explore potential targetable sites on ERα, discuss recent advancement of ERα inhibitor development, and highlight the potential opportunities and challenges of future ERα-directed drug discovery.

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Objectif

Produire un Outil national de soutien aux survivantes d’un cancer du sein (SSCS) qui facilite des soins appropriés, par les professionnels des soins primaires, aux patientes qui ont eu un cancer du sein après avoir terminé leur thérapie adjuvante.

Sources des données

Une recension a été effectuée dans MEDLINE et PubMed pour trouver des ouvrages publiés de 2002 à 2018 au moyen des mots clés en anglais breast cancer, survivorship, survivorship care plan, guideline, review, meta-analysis, chemotherapy, radiotherapy, treatment complications, adverse effects, late effects, screening, health promotion et follow up care. Les lignes directrices nationales et provinciales des organisations de cancérologie ont aussi fait l’objet d’une revue. Les données probantes sont classées comme étant de niveau I, II ou III.

Message principal

L’Outil SSCS présente un modèle fondé sur des données probantes pour assurer un transfert ininterrompu des soins des centres de cancérologie vers les soins primaires. Cet article explique les 4 étapes de la survie : la connaissance et la coordination des soins, la surveillance du cancer, la prise en charge des effets à long terme du traitement et la promotion de la santé.

Conclusion

L’Outil SSCS aidera les professionnels des soins primaires à assurer que les survivantes d’un cancer du sein reçoivent des soins de grande qualité et fondés sur des données probantes.

Breast Cancer Survivorship Tool: Facilitating breast cancer survivorship care for family physicians and patients

OBJECTIVE

To create an evidence-based national Breast Cancer Survivorship (BCS) Tool that facilitates appropriate care of breast cancer patients by primary care providers after patients have completed adjuvant therapy.

SOURCES OF INFORMATION

MEDLINE and PubMed were searched from 2002 to 2018 with the key words breast cancer, survivorship, survivorship care plan, guideline, review, meta-analysis, chemotherapy, radiotherapy, treatment complications, adverse effects, late effects, screening, health promotion, and follow up care. National or provincial cancer care organization guidelines were also reviewed. Evidence was graded as level I, II, or III.

MAIN MESSAGE

The BCS Tool provides an evidence-based template to ensure seamless transitions of care from cancer centres to primary care. Four steps of survivorship care are outlined in this article: care knowledge and coordination, cancer surveillance, management of long-term side effects of treatment, and health promotion.

CONCLUSION

The BCS Tool will support primary care providers in ensuring breast cancer survivors receive high-quality, evidence-based care.

The Effects of Pharmacological and Non-Pharmacological Interventions on Symptom Management and Quality of Life among Breast Cancer Survivors Undergoing Adjuvant Endocrine Therapy: A Systematic Review

Breast cancer survivors need to undergo adjuvant endocrine therapy after completion of curative treatments to prevent disease recurrence. These individuals often experience symptoms which are detrimental to their quality of life (QOL). Implementation of interventions for effective symptom management among these survivors is warranted. This review provides an overview of studies on the effectiveness of the previously developed interventions for breast cancer survivors undergoing adjuvant endocrine therapy on symptom alleviation and enhancement of QOL or health-related QOL (HRQOL). Five electronic databases were employed in the literature search. Study selection, data extraction and critical appraisal of the included studies were conducted by three authors independently. Twenty-four studies were included. Both pharmacological and non-pharmacological interventions are effective in addressing the symptoms associated with adjuvant endocrine therapy among the breast cancer survivors, and in improving their QOL, although discrepancies were noted between the studies in terms of the significance of these effects. Pharmacological and non-pharmacological interventions can be effective for symptom management among breast cancer survivors. Their implementation is recommended for effective survivorship care for these individuals. Further research on intervention development for breast cancer survivors is recommended to provide further evidence for the utility of the explored interventions in survivorship care for these patients.

Estrogen receptor-positive (ER+) breast cancer treatment: Are multi-target compounds the next promising approach?

Endocrine therapy is currently the main therapeutic approach for estrogen receptor-positive (ER⁺) breast cancer, the most frequent subtype of breast cancer in women worldwide. For this subtype of tumors, the current clinical treatment includes aromatase inhibitors (AIs) and anti-estrogenic compounds, such as Tamoxifen and Fulvestrant, being AIs the first-line treatment option for post-menopausal women. Moreover, the recent guidelines also suggest the use of these compounds by pre-menopausal women after suppressing ovaries function. However, besides its therapeutic efficacy, the prolonged use of this type of therapies may lead to the development of several adverse effects, as well as, endocrine resistance, limiting the effectiveness of such treatments. In order to surpass this issues and clinical concerns, during the last years, several studies have been suggesting alternative therapeutic approaches, considering the function of aromatase, ERα and ERβ. Here, we review the structural and functional features of these three targets and their importance in ER⁺ breast cancer treatment, as well as, the current treatment strategies used in clinic, emphasizing the importance of the development of multi-target compounds able to simultaneously modulate these key targets, as a novel and promising therapeutic strategy for this type of cancer.

Comparison of the roles of estrogens and androgens in breast cancer and prostate cancer

Breast cancer (BC) and prostate cancer (PC) are the second most common malignant tumors in women and men in western countries, respectively. The risks of death are 14% for BC and 9% for PC. Abnormal estrogen and androgen levels are related to carcinogenesis of the breast and prostate. Estradiol stimulates cancer development in BC. The effect of estrogen on PC is concentration-dependent, and estrogen can regulate androgen production, further affecting PC. Estrogen can also increase the risk of androgen-induced PC. Androgen has dual effects on BC via different metabolic pathways, and the role of the androgen receptor (AR) in BC also depends on cell subtype and downstream target genes. Androgen and AR can stimulate both primary PC and castration-resistant PC. Understanding the mechanisms of the effects of estrogen and androgen on BC and PC may help us to improve curative BC and PC treatment strategies.

Estrogen Receptor α (ERα)-targeting Compounds and Derivatives: Recent Advances in Structural Modification and Bioactivity

Breast cancer is the most common cancer suffered by female, and the second highest cause of cancer-related death among women worldwide. At present, hormone therapy is still the main treatment route and can be divided into three main categories: selective estrogen receptor modulators (SERMs), selective estrogen receptor downregulators (SERDs), and aromatase inhibitors (AIs). However, breast cancer is difficult to cure even after several rounds of anti-estrogen therapy and most drugs have serious side-effects. Here, we review the literature published over the past five years regarding the isolation and synthesis of analogs and their derivatives.

Heterogeneity of breast cancer: The importance of interaction between different tumor cell populations

INTRODUCTION

Breast cancer is the most common cancer and the second leading cause of cancer-related death in women worldwide. Despite the early detection of breast cancer and increasing knowledge of its biology and chemo-resistance, metastatic breast cancer is largely incurable disease. We provide a review of the intertumor and intratumor heterogeneity, explain the differences between triple-negative breast cancer subtypes. Also, we describe the interaction of breast tumor cells with their microenvironment cells and explain how this interaction contributes to the tumor progression, metastasis formation and resistance to the treatment.

DISCUSSION

One of the main causes that complicate the treatment is tumor heterogeneity. It is observed among patients (intertumor heterogeneity) and in each individual tumor (intratumor heterogeneity). In the case of intratumor heterogeneity, the tumor consists of different phenotypical cell populations. During breast cancer subtype identification, a small piece of solid tumor tissue does not necessarily represent all the tumor composition. Breast tumor cell phenotypical differences may appear due to cell localization in different tumor sites, unique response to the treatment, cell interaction with tumor microenvironment or tumor cell interaction with each other. This heterogeneity may lead to breast cancer aggressiveness and challenging treatment.

CONCLUSION

Understanding the molecular and cellular mechanisms of tumor heterogeneity that are relevant to the development of treatment resistance is a major area of research. Identification of differences between populations and their response to anticancer drugs would help to predict the potential resistance to chemotherapy and thus would help to select the most suitable anticancer treatment.