Targeting the androgen receptor in breast cancer

Stem cell-like circulating tumor cells identified by Pep@MNP and their clinical significance in pancreatic cancer metastasis

Objective

The circulating tumor cells (CTCs) could be captured by the peptide functionalized magnetic nanoparticles (Pep@MNP) detection system in pancreatic ductal adenocarcinoma (PDAC). CTCs and the CXCR4 expression were detected to explore their clinical significance. The CXCR4+ CTCs, this is highly metastatic-prone stem cell-like subsets of CTCs (HM-CTCs), were found to be associated with the early recurrence and metastasis of PDAC.

Methods

CTCs were captured by Pep@MNP. CTCs were identified via immunofluorescence with CD45, cytokeratin antibodies, and the CXCR4 positive CTCs were assigned to be HM-CTCs.

Results

The over-expression of CXCR4 could promote the migration of pancreatic cancer cell in vitro and in vivo. In peripheral blood (PB), CTCs were detected positive in 79.0% of all patients (49/62, 9 (0-71)/2mL), among which 63.3% patients (31/49, 3 (0-23)/2mL) were HM-CTCs positive. In portal vein blood (PVB), CTCs were positive in 77.5% of patients (31/40, 10 (0-40)/2mL), and 67.7% of which (21/31, 4 (0-15)/2mL) were HM-CTCs positive CTCs enumeration could be used as diagnostic biomarker of pancreatic cancer (AUC = 0.862), and the combination of CTCs positive and CA19-9 increase shows improved diagnostic accuracy (AUC = 0.963). in addition, PVB HM-CTCs were more accurate to predict the early recurrence and liver metastasis than PB HM-CTCs (AUC 0.825 vs. 0.787 and 0.827 vs. 0.809, respectively).

Conclusions

The CTCs identified by Pep@MNP detection system could be used as diagnostic and prognostic biomarkers of PDAC patients. We identified and defined the CXCR4 over-expressed CTC subpopulation as highly metastatic-prone CTCs, which was proved to identify patients who were prone to suffering from early recurrence and metastasis.

Cancer Screening for Transgender Individuals: Guidelines, Best Practices, and a Proposed Care Model

Few transgender-specific cancer screening recommendations exist. This review aims to cover current guidelines and practice patterns of cancer screening in transgender patients and, where evidence-based data are lacking, to draw from cisgender screening guidelines to suggest best practices for transgender patients based on anatomic inventory. Sufficient evidence does not exist to determine the long-term effects of gender-affirming hormone therapy on cancer risk. In the future, cancer screening and prevention should be focused on anatomic inventory and high-risk behaviors.

Efficacy of cell-free DNA as a diagnostic biomarker in breast cancer patients

Breast cancer is the most prevalent and leading cause of mortality worldwide among women. Cell-free DNA (cfDNA) analysis is an alternative quantitative approach to conventional methods for cancer diagnosis. The current research project aimed to determine the efficacy of cfDNA as a diagnostic biomarker in breast cancer patients in Pakistan. Eighty-four female breast cancer patients were selected as cases, and 152 healthy females as controls. Immunohistochemistry was performed to identify tumor biomarkers along with clinical profiling. cfDNA was extracted from serum using the phenol-chloroform method. The cfDNA level in the serum was estimated using Agarose Gel Electrophoresis and Nanodrop. SPPS version 25.0 was used to perform statistical analyses. The results showed that the cancer biomarkers were significantly associated with breast cancer. The changes in hematological parameters were insignificant, whereas the biochemical parameter variations between the cases and controls were statistically significant. A significant association of cfDNA level with breast cancer was observed. Further cfDNA levels and cancer biomarkers were not statistically significant. A significant correlation was observed between cfDNA and biochemical parameters, except for creatinine, whereas hematological parameters showed no significant correlation.ROC analysis declared cfDNA as an authentic diagnostic marker for breast cancer. It was concluded that the level of cfDNA is significantly increased in breast cancer patients and can be utilized as a diagnostic biomarker.

Core Needle Biopsy Accuracy for Androgen Receptor Expression in Invasive Breast Cancer

OBJECTIVE

 Breast cancer (BC) biomarkers, such as hormone receptors expression, are crucial to guide therapy in BC patients. Antiandrogens have been studied in BC; however, limited data are available on androgen receptor (AR) expression test methodology. We aim to report the core needle biopsy (CNB) accuracy for AR expression in BC.

METHODS

 Patients diagnosed with stage I-III invasive BC from a single institution were included. Androgen receptor expression was evaluated by immunohistochemistry (IHC) using 1 and 10% cutoff and the AR expression in surgical specimens (SS) was the gold standard. Kappa coefficients were used to evaluate the intraprocedural agreement.

RESULTS

 A total of 72 patients were included, with a mean age of 61 years old and 84% were Luminal A or B tumors. The prevalence of AR expression in all BC samples was 87.5% using a cutoff ≥ 10% in SS. With a cutoff value ≥ 1%, CNB had an accuracy of 95.8% (Kappa value = 0.645; 95% confidence interval [CI]: 0.272-1.000; p < 0.001) and 86.1% (Kappa value = 0.365; 95% CI: 0.052-0.679; p < 0.001) when ≥ 10% cutoff was used for AR positivity. Androgen receptor expression in CNB (cutoff ≥ 1%) had a sensitivity of 98.5%, specificity of 60%, positive predictive value of 97.0%, and a negative predictive value of 76.9% in the detection of AR expression in SS.

CONCLUSION

 Core needle biopsy has good accuracy in evaluating AR expression in BC. The accuracy of CNB decreases with higher cutoff values for AR positivity.

Integrins and Actions of Androgen in Breast Cancer

Androgen has been shown to regulate male physiological activities and cancer proliferation. It is used to antagonize estrogen-induced proliferative effects in breast cancer cells. However, evidence indicates that androgen can stimulate cancer cell growth in estrogen receptor (ER)-positive and ER-negative breast cancer cells via different types of receptors and different mechanisms. Androgen-induced cancer growth and metastasis link with different types of integrins. Integrin αvβ3 is predominantly expressed and activated in cancer cells and rapidly dividing endothelial cells. Programmed death-ligand 1 (PD-L1) also plays a vital role in cancer growth. The part of integrins in action with androgen in cancer cells is not fully mechanically understood. To clarify the interactions between androgen and integrin αvβ3, we carried out molecular modeling to explain the potential interactions of androgen with integrin αvβ3. The androgen-regulated mechanisms on PD-L1 and its effects were also addressed.

The prognostic value and immune microenvironment association of AR in HER2+ nonmetastatic breast cancer

This study aimed to investigate the prognostic value of AR in HER2+ nonmetastatic breast invasive ductal carcinoma (IDC) and its relationship with the immune microenvironment. HER2+ nonmetastatic breast IDC patients diagnosed by pathology who underwent surgery at Sun Yat-sen University Cancer Center from 2016 to 2017 were included. AR+ and AR- breast IDC samples were matched 1:1 in age, T stage, and N stage for immune infiltration analysis. A total of 554 patients with HER2+ nonmetastatic breast cancer were included in this retrospective study, regardless of HR status. The cut-off value for AR was set at 10%. ER+ (p < 0.001) and PR+ (p < 0.001) were associated with positive AR expression. Kaplan-Meier survival curve analysis suggested that AR was closely correlated with overall survival (OS) (p = 0.001) but not disease-free survival (DFS) (p = 0.051). After eliminating the potential impact caused by HR, AR also predicted longer OS (p = 0.014) and was an independent predictive factor for OS of HER2+HR- nonmetastatic breast IDC patients, as revealed by multivariate analysis (p = 0.036). For AR+ and AR- matched HER2+HR- patients, TILs (p = 0.043) and PD-L1 (p = 0.027) levels were significantly lower in AR+ patients. The strongest negative correlation was observed between AR and PD-L1 (Pearson's r = -0.299, p = 0.001). AR+ status was markedly related to better OS in HER2+HR- nonmetastatic breast cancer patients, while a negative correlation was observed between AR and PD-L1/TILs. We provide new insights into the prognostic value of AR and its association with the immune microenvironment to optimize treatment strategies in HER2+ nonmetastatic breast IDCs.

Prognostic value of androgen receptor expression in different molecular types of breast cancer in women

BACKGROUND

Breast cancer is a common women's disease. Usually, oestrogen is blamed in the aetiology and correlated with the prognosis; however, androgens are recently raising concern about its role in the breast cancer treatment and prognosis.

METHODS

In this study we retrieved archival paraffin blocks of breast cancer patients and stained it for androgen. Thereafter, we compared clinico-epidemiologic parameters, histopathology, neoadjuvant response and recurrence rate and pattern among patients with and without androgen receptor (AR) expression.

RESULTS

In total, 119 patients fulfilled enrolment criteria; AR expression were present in 77.3% of the patients. AR expression was associated with less grade III (6.8% versus 36.4%), and less triple negative (6.2% versus 25%), but similar overall recurrence rate (25% versus 22.2%). However, distant recurrence was significantly higher in androgen positive patients (91.3% versus 33.3% of all recurrences).

CONCLUSION

Androgen expression appears to be common among breast cancer, but with no clear implication in tumour aggressiveness or effect on the rate of recurrence. However, being commonly associated with distant spread may have an impact on survival of the patients.

Disparities in health condition diagnoses among aging transgender and cisgender medicare beneficiaries, 2008-2017

INTRODUCTION

The objective of this research is to provide national estimates of the prevalence of health condition diagnoses among age-entitled transgender and cisgender Medicare beneficiaries. Quantification of the health burden across sex assigned at birth and gender can inform prevention, research, and allocation of funding for modifiable risk factors.

METHODS

Using 2009-2017 Medicare fee-for-service data, we implemented an algorithm that leverages diagnosis, procedure, and pharmacy claims to identify age-entitled transgender Medicare beneficiaries and stratify the sample by inferred gender: trans feminine and nonbinary (TFN), trans masculine and nonbinary (TMN), and unclassified. We selected a 5% random sample of cisgender individuals for comparison. We descriptively analyzed (means and frequencies) demographic characteristics (age, race/ethnicity, US census region, months of enrollment) and used chi-square and t-tests to determine between- (transgender vs. cisgender) and within-group gender differences (e.g., TMN, TFN, unclassified) difference in demographics (p<0.05). We then used logistic regression to estimate and examine within- and between-group gender differences in the predicted probability of 25 health conditions, controlling for age, race/ethnicity, enrollment length, and census region.

RESULTS

The analytic sample included 9,975 transgender (TFN n=4,198; TMN n=2,762; unclassified n=3,015) and 2,961,636 cisgender (male n=1,294,690, female n=1,666,946) beneficiaries. The majority of the transgender and cisgender samples were between the ages of 65 and 69 and White, non-Hispanic. The largest proportion of transgender and cisgender beneficiaries were from the South. On average, transgender individuals had more months of enrollment than cisgender individuals. In adjusted models, aging TFN or TMN Medicare beneficiaries had the highest probability of each of the 25 health diagnoses studied relative to cisgender males or females. TFN beneficiaries had the highest burden of health diagnoses relative to all other groups.

DISCUSSION

These findings document disparities in key health condition diagnoses among transgender Medicare beneficiaries relative to cisgender individuals. Future application of these methods will enable the study of rare and anatomy-specific conditions among hard-to-reach aging transgender populations and inform interventions and policies to address documented disparities.

Impacts of COVID-19 in Breast Cancer: From Molecular Mechanism to the Treatment Approach

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has already infected more than 272 million people, resulting in 5.3 million deaths worldwide from COVID-19. Breast tumors are considered the world's most commonly diagnosed cancer. Both breast cancer and COVID-19 share common pathogenic features, represented by inflammatory mediators and the potential of SARS-CoV-2 replication in metastatic cancer cells. This may intensify viral load in patients, thereby triggering severe COVID-19 complications. Thus, cancer patients have a high risk of developing severe COVID-19 with SARS-CoV-2 infection and a higher rate of complications and death than non-cancer patients. The present review discusses common mechanisms between COVID-19 and breast cancer and the particular susceptibility to COVID-19 in breast cancer patients. We describe the effects of chemotherapeutic agents that are used against this cancer, which should be considered from the perspective of susceptibility to SARS-CoV-2 infection and risk of developing severe events. We also present potential drug interactions between chemotherapies that are used to treat breast cancer and drugs that are applied for COVID-19. The drugs that are identified as having the most interactions are doxorubicin and azithromycin. Both drugs can interact with each other and with other drugs, which likely requires additional drug monitoring and changes in drug dosage and timing of administration. Further clinical and observational studies involving breast cancer patients who acquire COVID-19 are needed to define the best therapeutic approach when considering the course of both diseases.

Correlation of TBK1, AR, and other serum cancer-related biomarkers in breast cancer patients: An observational study

Breast cancer (BC) ranks first for incidence and mortality in gynecological malignant tumors. This study aims to investigate the diagnostic value of Tank-binding kinase 1 (TBK1) and its correlation with androgen receptor (AR) and other serum cancer-related biomarkers in BC patient. The present observational study included 451 female BC patients and 451 healthy controls. Serum levels of TBK1, AR and other cancer-related biomarkers were detected in all the patients and healthy controls. Patients' demographic data and clinical data including age, body mass index (BMI), tumor node Metastasis (TNM), pathological type, tumor size and lymph node metastasis were collected. The follow-up lasted for 5 years. The deceased group had higher rate of patients with TNM III~IV, lymph node metastasis or tumor diameter >2. Deceased group had much higher rate of patients with negative ER and positive Ki67. Besides, increased TBK1 was found in BC patients with positive correlation with AR, CA15-3, CA125, CEA, and CA19-9. Serum TBK1 was associated with the clinic outcomes of BC patients and those with high TBK1 had lower 5-year survival rate. Moreover, cutoff value of 13.95 ng/mL TBK1 showed AUC of 0.981 (93.6% for sensitivity and 86.3% for specificity) for diagnosing BC, and cutoff value of 22.65 ng/mL TBK1 had AUC of 0.996 (97.7% for sensitivity and 96.3% for specificity) for diagnosing the death of BC patients. Serum TBK1 was positively correlated with AR and other serum cancer-related biomarkers. In addition, high TBK1 predicted the poor prognosis and might be used for the diagnosis of BC.

The obesity-breast cancer link: a multidisciplinary perspective

Obesity, exceptionally prevalent in the USA, promotes the incidence and progression of numerous cancer types including breast cancer. Complex, interacting metabolic and immune dysregulation marks the development of both breast cancer and obesity. Obesity promotes chronic low-grade inflammation, particularly in white adipose tissue, which drives immune dysfunction marked by increased pro-inflammatory cytokine production, alternative macrophage activation, and reduced T cell function. Breast tissue is predominantly composed of white adipose, and developing breast cancer readily and directly interacts with cells and signals from adipose remodeled by obesity. This review discusses the biological mechanisms through which obesity promotes breast cancer, the role of obesity in breast cancer health disparities, and dietary interventions to mitigate the adverse effects of obesity on breast cancer. We detail the intersection of obesity and breast cancer, with an emphasis on the shared and unique patterns of immune dysregulation in these disease processes. We have highlighted key areas of breast cancer biology exacerbated by obesity, including incidence, progression, and therapeutic response. We posit that interception of obesity-driven breast cancer will require interventions that limit protumor signaling from obese adipose tissue and that consider genetic, structural, and social determinants of the obesity–breast cancer link. Finally, we detail the evidence for various dietary interventions to offset obesity effects in clinical and preclinical studies of breast cancer. In light of the strong associations between obesity and breast cancer and the rising rates of obesity in many parts of the world, the development of effective, safe, well-tolerated, and equitable interventions to limit the burden of obesity on breast cancer are urgently needed.

Impact of Androgen Receptor Expression and the AR:ER Ratio on the Survival Outcomes in the Diverse Subgroups of Vietnamese Breast Cancer: A Single Institutional Retrospective Cohort Analysis

Background: The androgen receptor (AR) has recently emerged as a useful marker for the more favorable prognosis and better outcomes among women with estrogen receptor (ER) + ve breast cancer (BC) and the further refinement of BC subtype. Furthermore, AR expression in ER − ve tumors has a particular prognostic significance. Additionally, the ratio of nuclear AR to ER may critically have an influence on tumor biology and respond to endocrine therapy. Purpose: To define the AR expression and AR:ER ratio, and explored their correlation with the clinicopathological features, prognosis, and survival outcomes in the various subclasses of invasive BC. Methods: The current study was conducted on 522 BC patients who had surgical operations, without neoadjuvant chemotherapy by applying a retrospective cohort analysis. The clinicopathological characteristics were recorded. Immunohistochemical staining was performed on AR, ER, PR, HER2, and Ki67. Expression of AR was paired into different immunophenotypes for analysis with clinicopathological features and survival. All BC patients’ survival was analyzed using Kaplan–Meier and log-rank models. Results: The presence of AR was detected in 65.3%. Positive AR, the ratio of AR:ER<2, luminal androgen receptor (LAR) + and AR + HER2 + immunophenotypes were significantly associated with better prognostic features. AR:ER<2 was observed in the prolonged overall survival (OS) and disease-free survival (DFS) (87.9 and 86.2%, respectively) compared to AR:ER≥2 (25.0% in both) (P < .001). In contrast, in HR + ve BCs, the AR expression was not significantly correlated with survival. The multivariate model revealed that the ratio of nuclear AR to ER remained as an independent prognostic variable. Conclusion: The AR expression had a distinct OS and DFS. The AR:ER ratio is an independent indicator for predicting the OS and DFS of BC patients in both univariate and multivariate analyses.

Estrogen and Estrogen Receptor Modulators: Potential Therapeutic Strategies for COVID-19 and Breast Cancer

Owing to the ongoing coronavirus disease 2019 (COVID-19) pandemic, we need to pay a particular focus on the impact of coronavirus infection on breast cancer patients. Approximately 70% of breast cancer patients express estrogen receptor (ER), and intervention therapy for ER has been the primary treatment strategy to prevent the development and metastasis of breast cancer. Recent studies have suggested that selective estrogen receptor modulators (SERMs) are a potential therapeutic strategy for COVID-19. With its anti-ER and anti-viral combined functions, SERMs may be an effective treatment for COVID-19 in patients with breast cancer. In this review, we explore the latent effect of SERMs, especially tamoxifen, and the mechanism between ER and virus susceptibility.

The Other Side of the Coin: May Androgens Have a Role in Breast Cancer Risk?

Breast cancer prevention is a major challenge worldwide. During the last few years, efforts have been made to identify molecular breast tissue factors that could be linked to an increased risk of developing the disease in healthy women. In this concern, steroid hormones and their receptors are key players since they are deeply involved in the growth, development and lifetime changes of the mammary gland and play a crucial role in breast cancer development and progression. In particular, androgens, by binding their own receptor, seem to exert a dichotomous effect, as they reduce cell proliferation in estrogen receptor α positive (ERα+) breast cancers while promoting tumour growth in the ERα negative ones. Despite this intricate role in cancer, very little is known about the impact of androgen receptor (AR)-mediated signalling on normal breast tissue and its correlation to breast cancer risk factors. Through an accurate collection of experimental and epidemiological studies, this review aims to elucidate whether androgens might influence the susceptibility for breast cancer. Moreover, the possibility to exploit the AR as a useful marker to predict the disease will be also evaluated.

SARS-CoV-2 spike protein and RNA dependent RNA polymerase as targets for drug and vaccine development: A review

The present pandemic has posed a crisis to the economy of the world and the health sector. Therefore, the race to expand research to understand some good molecular targets for vaccine and therapeutic development for SARS-CoV-2 is inevitable. The newly discovered coronavirus 2019 (COVID-19) is a positive sense, single-stranded RNA, and enveloped virus, assigned to the beta CoV genus. The virus (SARS-CoV-2) is more infectious than the previously detected coronaviruses (MERS and SARS). Findings from many studies have revealed that S protein and RdRp are good targets for drug repositioning, novel therapeutic development (antibodies and small molecule drugs), and vaccine discovery. Therapeutics such as chloroquine, convalescent plasma, monoclonal antibodies, spike binding peptides, and small molecules could alter the ability of S protein to bind to the ACE-2 receptor, and drugs such as remdesivir (targeting SARS-CoV-2 RdRp), favipir, and emetine could prevent SASR-CoV-2 RNA synthesis. The novel vaccines such as mRNA1273 (Moderna), 3LNP-mRNAs (Pfizer/BioNTech), and ChAdOx1-S (University of Oxford/Astra Zeneca) targeting S protein have proven to be effective in combating the present pandemic. Further exploration of the potential of S protein and RdRp is crucial in fighting the present pandemic.

A First-in-Human Phase 1 Study of a Novel Selective Androgen Receptor Modulator (SARM), RAD140, in ER+/HER2- Metastatic Breast Cancer

INTRODUCTION/BACKGROUND

This first-in-human, phase 1 study aimed to characterize the safety, tolerability, maximum tolerated dose (MTD), pharmacokinetic (PK) profile, and antitumor activity of RAD140, an oral selective androgen receptor (AR) modulator (SARM).

PATIENTS AND METHODS

This dose-escalation study with a 3 + 3 design and PK expansion cohort enrolled postmenopausal women with ER+/HER2- metastatic breast cancer (mBC). Serum sex hormone-binding globulin (SHBG) and prostate-specific antigen (PSA) were used as surrogate markers of AR engagement.

RESULTS

Twenty-two (21 AR+) heavily pretreated mBC patients were enrolled. Dose levels included 50 mg (n = 6), 100 mg (n = 13), and 150 mg (n = 3) once daily (QD). Most frequent (> 10%) treatment-emergent adverse events (TEAEs) were elevated AST (59.1%), ALT (45.5%), and total blood bilirubin (27.3%), and vomiting, dehydration, and decreased appetite and weight (27.3% each). Grade 3/4 TEAEs occurred in 16 (72.7%) patients and included elevations in AST/ALT and hypophosphatemia (22.7% each). Treatment-related TEAEs occurred in 17 per 22 patients (77.3%); 7 (31.8%) were Grade 3; none were Grade 4. The half-life (t_1/2) of 44.7 hours supported QD dosing. At the MTD of 100 mg/day, 1 patient with an ESR1 mutation at baseline had a partial response. Overall, clinical benefit rate at 24 weeks was 18.2%, and median progression-free survival was 2.3 months. SHBG decreased in 18 per 18 patients, and PSA increased in 16 per 20 patients. Paired baseline and on-treatment tumor biopsies demonstrated AR engagement.

CONCLUSION

RAD140 is a novel oral AR-targeted agent for the treatment of AR+/ER+/HER2- mBC with an acceptable safety profile and preliminary evidence of target engagement and antitumor activity.

The role of androgens in women's health and wellbeing

Androgens in women, as well as in men, are intrinsic to maintenance of (i) reproductive competency, (ii) cardiac health, (iii) appropriate bone remodeling and mass retention, (iii) muscle tone and mass, and (iv) brain function, in part, through their mitigation of neurodegenerative disease effects. In recognition of the pluripotency of endogenous androgens, exogenous androgens, and selected congeners, have been prescribed off-label for several decades to treat low libido and sexual dysfunction in menopausal women, as well as, to improve physical performance. However, long-term safety and efficacy of androgen administration has yet to be fully elucidated. Side effects often observed include (i) hirsutism, (ii) acne, (iii) deepening of the voice, and (iv) weight gain but are associated most frequently with supra-physiological doses. By contrast, short-term clinical trials suggest that the use of low-dose testosterone therapy in women appears to be effective, safe and economical. There are, however, few clinical studies, which have focused on effects of androgen therapy on pre- and post-menopausal women; moreover, androgen mechanisms of action have not yet been thoroughly explained in these subjects. This review considers clinical effects of androgens on women's health in order to prevent chronic diseases and reduce cancer risk in gynecological tissues.

Breast Cancer: Targeting of Steroid Hormones in Cancerogenesis and Diagnostics

Breast cancer is the most common malignancy in women with high mortality. Sensitive and specific methods for the detection, characterization and quantification of endogenous steroids in body fluids or tissues are needed for the diagnosis, treatment and prognosis of breast cancer and many other diseases. At present, non-invasive diagnostic methods are gaining more and more prominence, which enable a relatively fast and painless way of detecting many diseases. Metabolomics is a promising analytical method, the principle of which is the study and analysis of metabolites in biological material. It represents a comprehensive non-invasive diagnosis, which has a high potential for use in the diagnosis and prognosis of cancers, including breast cancer. This short review focuses on the targeted metabolomics of steroid hormones, which play an important role in the development and classification of breast cancer. The most commonly used diagnostic tool is the chromatographic method with mass spectrometry detection, which can simultaneously determine several steroid hormones and metabolites in one sample. This analytical procedure has a high potential in effective diagnosis of steroidogenesis disorders. Due to the association between steroidogenesis and breast cancer progression, steroid profiling is an important tool, as well as in monitoring disease progression, improving prognosis, and minimizing recurrence.

Advanced Approaches to Breast Cancer Classification and Diagnosis

The International Agency for Research on Cancer (IARC) has recently reported a 66% increase in the global number of cancer deaths since 1960. In the US alone, about one in eight women is expected to develop invasive breast cancer(s) (breast cancer) at some point in their lifetime. Traditionally, a BC diagnosis includes mammography, ultrasound, and some high-end molecular bioimaging. Unfortunately, these techniques detect BC at a later stage. So early and advanced molecular diagnostic tools are still in demand. In the past decade, various histological and immuno-molecular studies have demonstrated that BC is highly heterogeneous in nature. Its growth pattern, cytological features, and expression of key biomarkers in BC cells including hormonal receptor markers can be utilized to develop advanced diagnostic and therapeutic tools. A cancer cell's progression to malignancy exhibits various vital biomarkers, many of which are still underrepresented in BC diagnosis and treatment. Advances in genetics have also enabled the development of multigene assays to detect genetic heterogeneity in BC. However, thus far, the FDA has approved only four such biomarkers-cancer antigens (CA); CA 15-3, CA 27-29, Human epidermal growth factor receptor 2 (HER2), and circulating tumor cells (CTC) in assessing BC in body fluids. An adequately structured portable-biosensor with its non-invasive and inexpensive point-of-care analysis can quickly detect such biomarkers without significantly compromising its specificity and selectivity. Such advanced techniques are likely to discriminate between BC and a healthy patient by accurately measuring the cell shape, structure, depth, intracellular and extracellular environment, and lipid membrane compositions. Presently, BC treatments include surgery and systemic chemo- and targeted radiation therapy. A biopsied sample is then subjected to various multigene assays to predict the heterogeneity and recurrence score, thus guiding a specific treatment by providing complete information on the BC subtype involved. Thus far, we have seven prognostic multigene signature tests for BC providing a risk profile that can avoid unnecessary treatments in low-risk patients. Many comparative studies on multigene analysis projected the importance of integrating clinicopathological information with genomic-imprint analysis. Current cohort studies such as MINDACT, TAILORx, Trans-aTTOM, and many more, are likely to provide positive impact on long-term patient outcome. This review offers consolidated information on currently available BC diagnosis and treatment options. It further describes advanced biomarkers for the development of state-of-the-art early screening and diagnostic technologies.

Estrogen and Androgen Receptor Inhibitors: Unexpected Allies in the Fight Against COVID-19

Translational Relevance

No prophylactic treatments for COVID-19 have been clearly proven and found. In this pandemic context, cancer patients constitute a particularly fragile population that would benefit the best from such treatments, a present unmet need. TMPRSS2 is essential for COVID-19 replication cycle and it is under androgen control. Estrogen and androgen receptor dependent cues converge on TMPRSS2 regulation through different mechanisms of action that can be blocked by the use of hormonal therapies. We believe that there is enough body of evidence to foresee a prophylactic use of hormonal therapies against COVID-19 and this hypothesis can be easily tested on cohorts of breast and prostate cancer patients who follow those regimens. In case of pandemic, if the protective effect of hormonal therapies will be proven on cancer patients, the use of specific hormonal therapies could be extended to other oncological groups and to healthy individuals to decrease the overall risk of infection by SARS-CoV-2.

Given the COVID-19 coronavirus emergency, a special focus is needed on the impact of this rapidly spreading viral infection on cancer patients. Androgen receptor (AR) signaling in the transmembrane protease serine 2 (TMPRSS2) regulation is emerging as an important determinant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) susceptibility. In our study, we analyzed AR and TMPRSS2 expression in 17,352 normal and 9,556 cancer tissues from public repositories and stratified data according to sex and age. The emerging picture is that some patient groups may be particularly susceptible to SARS-CoV-2 infection and may benefit from antiandrogen- or tamoxifen-based therapies. These findings are relevant to choose proper treatments in order to protect cancer patients from concomitant SARS-CoV-2 contagion and related symptoms and put forward the idea that hormonal therapies could be used as prophylactic agents against COVID-19.

Cancer screening in the transgender population: a review of current guidelines, best practices, and a proposed care model

Over the last 50 years cancer mortality has decreased, the biggest contributor to this decrease has been the widespread adoption of cancer screening protocols. These guidelines are based on large population studies, which often do not capture the non-gender conforming portion of the population. The aim of this review is to cover current guidelines and practice patterns of cancer screening in transgender patients, and, where evidence-based data is lacking, to draw from cis-gender screening guidelines to suggest best-practice screening approaches for transgender patients. We performed a systematic search of PubMed, Google Scholar and Medline, using all iterations of the follow search terms: transgender, gender non-conforming, gender non-binary, cancer screening, breast cancer, ovarian cancer, uterine cancer, cervical cancer, prostate cancer, colorectal cancer, anal cancer, and all acceptable abbreviations. Given the limited amount of existing literature inclusion was broad. After eliminating duplicates and abstract, all queries yielded 85 unique publications. There are currently very few transgender specific cancer screening recommendations. All the guidelines discussed in this manuscript were designed for cis-gender patients and applied to the transgender community based on small case series. Currently, there is not sufficient to evidence to determine the long-term effects of gender-affirming hormone therapy on an individual’s cancer risk. Established guidelines for cisgender individuals and can reasonably followed for transgender patients based on what organs remain in situ. In the future comprehensive cancer screening and prevention initiatives centered on relevant anatomy and high-risk behaviors specific for transgender men and women are needed.

Luteolin suppresses androgen receptor-positive triple-negative breast cancer cell proliferation and metastasis by epigenetic regulation of MMP9 expression via the AKT/mTOR signaling pathway

BACKGROUND

Triple-negative breast cancer (TNBC) represents up to 20% of all breast cancers. This cancer lacks the expression of the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. The current therapeutic strategy for patients with this subtype is the use of cytotoxic chemotherapy and surgery. Luteolin is a natural herbal flavonoid and a potential therapeutic candidate for multiple diseases. The use of a treatment that combines Chinese herbal medicine and western medicine is rising in Asia.

PURPOSE

The present study evaluates the effects and molecular mechanisms involved with luteolin treatment and evaluates whether this herb affects androgen receptor-positive breast cancer cell proliferation or metastasis.

STUDY DESIGN

In vitro evaluation of the effect of luteolin on androgen receptor-positive TNBC cell proliferation and metastasis METHODS: Cell viability analysis was used for the cytotoxicity test. Colony formation and Bromodeoxyuridine (BrdU) staining-based proliferation experiments were used for cell proliferation. Wound healing and transwell assays were used for in vitro migration/invasion. The RT-qPCR analysis was used for gene expression. Furthermore, ChIP-qPCR analysis was used for epigenetic modification of gene promoters.

RESULTS

Luteolin significantly inhibited the proliferation and metastasis of androgen receptor-positive TNBC. Furthermore, luteolin inactivated the AKT/mTOR signaling pathway and reversed the epithelial-mesenchymal transition (EMT). The combination of luteolin and inhibitors of AKT/mTOR synergistically repressed an androgen receptor-positive TNBC cell proliferation and metastasis. Luteolin also downregulated MMP9 expression by decreasing the levels of the AKT/mTOR promoting H3K27Ac and H3K56A on the MMP9 promoter region.

CONCLUSION

Our findings indicate that luteolin inhibited the proliferation and metastasis of androgen receptor-positive TNBC by regulating MMP9 expression through a reduction in the levels of AKT/mTOR-inducing H3K27Ac and H3K56Ac.

Contrasting activities of estrogen receptor beta isoforms in triple negative breast cancer

PURPOSE

Triple negative breast cancer (TNBC), an aggressive subtype of breast cancer, lacks the three major receptors for predicting outcome or targeting therapy. Hence, our aim was to evaluate the potential of estrogen receptor beta (ERβ) as a possible endocrine therapy target in TNBC.

METHODS

The expression and prognostic effect of ERβ isoforms were analyzed using TCGA breast tumor data, and the expression of ERβ isoform mRNA and protein in TNBC cell lines was assayed. Endogenous ERβ2 and ERβ5 were knocked down with siRNA, and ERβ2, ERβ5, and ERβ1 were upregulated using a doxycycline-inducible lentiviral system. Cell proliferation, migration and invasion, and specific gene expressions were evaluated.

RESULTS

ERβ2 and ERβ5 were the predominant endogenous forms of ERβ in TNBC tumors and cell lines. High ERβ2 predicted worse clinical outcome. Knockdown of endogenous ERβ2/ERβ5 in cell lines suppressed proliferation, migration and invasion, and downregulated proto-oncogene survivin expression. ERβ2/ERβ5 upregulation did the reverse, increasing survivin and these cell activities. ERβ1 was barely detectable in TNBC cell lines, but its upregulation reduced survivin, increased tumor suppressor expression (E-cadherin and cystatins), and suppressed proliferation, migration and invasion in both ligand-independent and dependent manners, suggesting the possible translational benefit of ERβ ligands.

CONCLUSIONS

ERβ2/ERβ5 and ERβ1 exhibit sharply contrasting activities in TNBC cells. Our findings imply that delineating the absolute amounts and relative ratios of the different ERβ isoforms might have prognostic and therapeutic relevance, and could enable better selection of optimal approaches for treatment of this often aggressive form of breast cancer.

Androgen receptor expression in a Sri Lankan patient cohort with early breast carcinoma

BACKGROUND

Androgen receptor (AR) expression is emerging as a prognostic biomarker in breast carcinoma (BCa). The study aimed to determine the prevalence of AR expression by immunohistochemical analysis among a cohort of Sri Lankan women with early BCa and to evaluate its association with clinicopathological features including immunohistochemical molecular subtype and early survival.

METHOD

We studied the clinical and pathological features and immunohistochemical profile of 141 women undergoing primary surgery for early BCa, followed by standard adjuvant therapy. AR status was assessed by immunohistochemistry in all cases. Overall survival (OS) and disease-free survival (DFS) was determined. The relationship between AR expression and clinical and pathological parameters and immunohistochemical molecular subtype was analyzed using Student T test and chi-square tests. Cox regression analysis was used to analyze the prognostic impact of AR expression.

RESULTS

AR expression was seen in 40.8%(95%CI 33.10-49.07%) of the BCa study cohort. None of the clinical data studied showed a significant association with the AR status(p > 0.05). Ductal carcinoma in situ(p = 0.003), oestrogen receptor (ER) (p = 0.001) and progesterone receptor (PR) (p = 0.001) positivity and luminal IHC molecular subtype(p = 0.016) were significantly associated with AR-positive status. AR-negative status was significantly associated with tumour necrosis > 50%(p = 0.031), moderate to extensive lymphocytic infiltrate at the tumour margin(p = 0.025) and basal triple negative breast carcinoma(p = 0.016). The mean duration of patient follow-up was 46.70(95% CI 46.495-46.905) months (3.89 years). On univariate analysis, AR-positivity was associated with better OS among ER-positive tumours(p = 0.047), specifically in postmenopausal women (p = 0.030). In ER-negative tumours, AR positivity was associated with worse DFS (p = 0.036). On multivariate analysis, TNM stage and ER/AR status were predictive of survival. ER-positive/AR-positive (ER+/AR+) tumours demonstrated better OS than ER-positive/AR-negative (ER+/AR-) tumours(p = 0.015). ER-negative/AR-positive (ER-/AR+) tumours (p = 0.014) had a worse DFS than ER-negative/AR-negative (ER-/AR-) tumours.

CONCLUSIONS

AR prevalence obtained was low. AR positivity was associated with positivity for ER and PR. On multivariate analysis, apart from TNM stage only ER/AR status were predictive of OS and DFS, with concordant expression of ER/AR demonstrating a better, early survival.

Circulating Tumor Cells Expressing the Prostate Specific Membrane Antigen (PSMA) Indicate Worse Outcome in Primary, Non-Metastatic Triple-Negative Breast Cancer

Background: We analyzed mRNA profiles of prostate cancer related genes in circulating tumor cells (CTCs) of primary, non-metastatic triple-negative breast cancer (TNBC) patients (pts) before and after neoadjuvant chemotherapy to elucidate the potential of prostate cancer targets in this BC subgroup.

Method: Blood from 41 TNBC pts (n = 41 before / 26 after therapy) was analyzed for CTCs applying the AdnaTest EMT-2/Stem Cell Select. Multimarker RT-qPCR allowed the detection of the prostate specific antigen PSA, the prostate specific membrane antigen PSMA, full-length androgen receptor (AR-FL), and AR splice-variant seven (AR-V7).

Results: Before therapy, at least one prostate cancer related gene was detected in 15/41 pts (37%). Notably, in 73% of AR-FL positive cases, AR-V7 was co-expressed. After therapy, CTCs of only one patient harbored prostate cancer related genes. AR-V7+ and PSMA+ CTCs significantly correlated with early relapse (p = 0.041; p = 0.00039) whereas PSMA+ CTCs also associated with a reduced OS (p = 0.0059). This correlation was confirmed for PSMA+ CTCs in univariate (PFS p = 0.002; OS p = 0.015), but not multivariate analysis.

Conclusion: Although CTCs that expressed prostate cancer related genes were eliminated by the given therapy, PSMA+ CTCs significantly identified pts at high risk for relapse. Furthermore, AR inhibition, often discussed for this BC subgroup, might not be successful in the primary setting of the disease since we identified AR-FL+ CTCs together with AR-V7+ CTCs, associated with therapeutic failure.

Distribution and characteristics of androgen receptor (AR) in breast cancer among women in Addis Ababa, Ethiopia: A cross sectional study

Evaluation of the role of androgen receptor (AR) in the biology of breast cancer is an emerging area of research. There are compelling evidences that AR expression may be used to further refine breast cancer molecular subtyping with prognostic and therapeutic implications. Many studies indicated co-expression of AR with the hormonal receptors in breast cancer has a favorable prognosis. AR is also investigated by many researchers as a potential therapeutic target in treatment of breast cancer. Studies on the frequency and distribution of AR in breast cancer among Africans is barely available. Given the heightened interest to understand its role in breast cancer, we determined AR expression and assessed its association with clinicopathological parameters among Ethiopian women. In this study, 112 newly diagnosed patient with invasive breast cancer at Tikur Anbessa Specialized Hospital were enrolled. Immunohistochemical assessment of AR, ER, PR, Ki67 and HER2 were performed using tissue microarrays (TMA) constructed from their primary tumor block. Out of the 112 participants, 91 (81%) were positive for AR expression and the remaining 21 participants (19%) were negative for AR expression. Expression of AR in ER+, HER2+ and TNBC cases were 93%, 83% and 48% respectively. Our study reveals AR is expressed in a significant number of breast cancers patients and this may indicate that breast cancers cases in Ethiopia have favorable prognosis and could benefit from progresses in AR targeted treatments. Since AR expression has important consequences on the prognosis and treatment of breast cancer, further studies with an increased number of participants is necessary to confirm our reports.

Sex steroid hormone function in the brain niche: Implications for brain metastatic colonization and progression

BACKGROUND

While sex hormones and their receptors play well-known roles in progression of primary tumors through direct action on sex steroid hormone-responsive cancer cells, emerging evidence suggest that hormones also play important roles in metastatic progression by modulating the tumor microenvironment. Estrogens and androgens synthesized in gonads and within the brain influence memory, behavior, and outcomes of brain pathologies. Yet, their impact on brain metastatic colonization and progression is just beginning to be explored.

RECENT FINDINGS

Estradiol and testosterone cross the blood-brain barrier and are synthesized de novo in astrocytes and other cells within the adult brain. Circulating and brain-synthesized estrogens have been shown to promote brain metastatic colonization of tumors lacking estrogen receptors (ERs), through mechanisms involving the upregulation of growth factors and neurotrophins in ER+ reactive astrocytes. In this review, we discuss additional mechanisms by which hormones may influence brain metastases, through modulation of brain endothelial cells, astrocytes, and microglia.

CONCLUSION

A greater understanding of hormone-brain-tumor interactions may shed further light on the mechanisms underlying the adaptation of cancer cells to the brain niche, and provide therapeutic alternatives modulating the brain metastatic niche.

Targeting cancer cells with nanotherapeutics and nanodiagnostics: Current status and future perspectives

Nanotechnology is reshaping health care strategies and is expected to exert a tremendous impact in the coming years offering better healthcare facilities. It has led to not only therapeutic drug delivery feasibility but also to diagnostics. Materials in the size of nano range (1-100 nm) used in the design, fabrication, regulation, and application of therapeutic drugs or devices are classified as medical nanotechnology and nanopharmacology. Delivery of more complex molecules to the specific site of action as well as gene therapy has pushed forward the nanoparticle-based drug delivery to its maximum. Areas that benefit from nano-based drug delivery systems are cancer, diabetes, infectious diseases, neurodegenerative diseases, blood disorders and orthopedic-related ailments. Moreover, development of nanotherapeutics with multi-functionalities has a considerable potential to fill the gaps that exist in the present therapeutic domain. In cancer treatment, nanomedicines have superiority over current therapeutic practices as they can effectively deliver the drug to the affected tissues, thus reducing drug toxicities. Along this line, polymeric conjugates of asparaginase and polymeric micelles of paclitaxel have recently been recommended for the treatment of various types of cancers. Nanotechnology-based therapeutics and diagnostics provide greater effectiveness with less or no toxicity concerns. Similarly, diagnostic imaging holds promising future applications with newer nano-level imaging elements. Advancements in nanotechnology have emerged to a newer direction which use nanorobotics for various applications in healthcare. Accordingly, this review comprehensively highlights the potentialities of various nanocarriers and nanomedicines for multifaceted applications in diagnostics and drug delivery, especially the potentialities of polymeric nanoparticle, nanoemulsion, solid-lipid nanoparticle, nanostructured lipid carrier, self-micellizing anticancer lipids, dendrimer, nanocapsule and nanosponge-based therapeutic approaches in the field of cancer. Furthermore, this article summarizes the most recent literature pertaining to the use of nano-technology in the field of medicine, particularly in treating cancer patients.

Androgen Receptor in Breast Cancer: From Bench to Bedside

Breast cancer (BC) is one of the most common malignancies and the leading cause of cancer-related mortality in women. Androgen receptor (AR) is frequently expressed in diverse BC subtypes. Accumulating evidence has revealed that AR might be a predictive or prognostic factor and a drug target in BC. AR expression and AR pathways differ in various BC subtypes, thereby resulting in controversial inferences on the predictive and prognostic value of AR. Herein, we summarized the roles of AR in different BC subtypes and AR-targeting therapies based on preclinical and clinical studies. Moreover, we highlighted the possible efficacy of a combination therapy via exploiting the AR-related mechanisms and the research on therapeutic resistance.

Cancer Risk in Transgender People

Gender-affirming hormonal treatment (HT) in transgender people is considered safe in general, but the question regarding (long-term) risk on sex hormone-related cancer remains. Because the risk on certain types of cancer differs between men and women, and some of these differences are attributed to exposure to sex hormones, the cancer risk may be altered in transgender people receiving HT. Although reliable epidemiologic data are sparse, the available data will be discussed in this article. Furthermore, recommendations for cancer screening and prevention will be discussed as well as whether to withdraw HT at time of a cancer diagnosis.

Phase II Study of Dehydroepiandrosterone in Androgen Receptor-Positive Metastatic Breast Cancer

LESSONS LEARNED

The androgen receptor (AR) is present in most breast cancers (BC), but its exploitation as a therapeutic target has been limited.This study explored the activity of dehydroepiandrosterone (DHEA), a precursor being transformed into androgens within BC cells, in combination with an aromatase inhibitor (to block DHEA conversion into estrogens), in a two-stage phase II study in patients with AR-positive/estrogen receptor-positive/human epidermal growth receptor 2-negative metastatic BC.Although well tolerated, only 1 of 12 patients obtained a prolonged clinical benefit, and the study was closed after its first stage for poor activity.

BACKGROUND

Androgen receptors (AR) are expressed in most breast cancers, and AR-agonists have some activity in these neoplasms. We investigated the safety and activity of the androgen precursor dehydroepiandrosterone (DHEA) in combination with an aromatase inhibitor (AI) in patients with AR-positive metastatic breast cancer (MBC).

METHODS

A two-stage phase II study was conducted in two patient cohorts, one with estrogen receptor (ER)-positive (resistant to AIs) and the other with triple-negative MBC. DHEA 100 mg/day was administered orally. The combination with an AI aimed to prevent the conversion of DHEA into estrogens. The main endpoint was the clinical benefit rate. The triple-negative cohort was closed early.

RESULTS

Twelve patients with ER-positive MBC were enrolled. DHEA-related adverse events, reported in four patients, included grade 2 fatigue, erythema, and transaminitis, and grade 1 drowsiness and musculoskeletal pain. Clinical benefit was observed in one patient with ER-positive disease whose tumor had AR gene amplification. There was wide inter- and intra-patient variation in serum levels of DHEA and its metabolites.

CONCLUSION

DHEA showed excellent safety but poor activity in MBC. Although dose and patient selection could be improved, high serum level variability may hamper further DHEA development in this setting.

Breast cancer risk in transgender people receiving hormone treatment: nationwide cohort study in the Netherlands

OBJECTIVE

To investigate the incidence and characteristics of breast cancer in transgender people in the Netherlands compared with the general Dutch population.

DESIGN

Retrospective, nationwide cohort study.

SETTING

Specialised tertiary gender clinic in Amsterdam, the Netherlands.

PARTICIPANTS

2260 adult trans women (male sex assigned at birth, female gender identity) and 1229 adult trans men (female sex assigned at birth, male gender identity) who received gender affirming hormone treatment.

MAIN OUTCOME MEASURES

Incidence and characteristics (eg, histology, hormone receptor status) of breast cancer in transgender people.

RESULTS

The total person time in this cohort was 33 991 years for trans women and 14 883 years for trans men. In the 2260 trans women in the cohort, 15 cases of invasive breast cancer were identified (median duration of hormone treatment 18 years, range 7-37 years). This was 46-fold higher than in cisgender men (standardised incidence ratio 46.7, 95% confidence interval 27.2 to 75.4) but lower than in cisgender women (0.3, 0.2 to 0.4). Most tumours were of ductal origin and oestrogen and progesterone receptor positive, and 8.3% were human epidermal growth factor 2 (HER2) positive. In 1229 trans men, four cases of invasive breast cancer were identified (median duration of hormone treatment 15 years, range 2-17 years). This was lower than expected compared with cisgender women (standardised incidence ratio 0.2, 95% confidence interval 0.1 to 0.5).

CONCLUSIONS

This study showed an increased risk of breast cancer in trans women compared with cisgender men, and a lower risk in trans men compared with cisgender women. In trans women, the risk of breast cancer increased during a relatively short duration of hormone treatment and the characteristics of the breast cancer resembled a more female pattern. These results suggest that breast cancer screening guidelines for cisgender people are sufficient for transgender people using hormone treatment.

Androgen Receptors in Resected Ductal Carcinoma In Situ of Breast: Novel Insights With Possible Implications for Testing and Targeted Endocrine Chemoprevention Trials

Mammary ductal carcinoma in situ (DCIS) is classically treated by combinations of excision, radiation, and endocrine therapy, based upon the specific needs of individual patients. Estrogen receptor (ER) status is generally assessed by immunohistochemistry (IHC) in newly diagnosed cases of DCIS, and endocrine therapy in this setting is thought to be chemopreventive. The potential impact of androgens on mammary carcinogenesis has been studied in recent years, and several authors have proposed androgen receptor (AR) IHC testing and targeted antiandrogenic therapy in patients with locally advanced or metastatic triple-negative invasive breast cancer (ie, negative for ER and progesterone receptor and HER-2). Very little has been published on AR in DCIS. We report results of AR IHC on archival tissue blocks from 221 adult female patients, each of whom underwent definitive breast resection of DCIS. Of the 221 cases, 72 (33%) were shown to express AR in their DCIS at or above the 10% threshold often used for invasive carcinoma. AR expression was seen in all grades of DCIS. Of the 72 positive AR cases, 21 (29%) were ER negative, corresponding to 10% (21/221) of all patients. The majority of the AR-positive cases were high grade, and the most common histologic subtype in this subset was a solid growth pattern with apocrine features. Early data from clinical trials evaluating AR antagonists in invasive/metastatic triple-negative breast cancer suggest that some patients may benefit from androgen blockade. IHC testing and potential clinical trials of AR antagonists for chemoprevention in patients with AR-positive and ER-negative DCIS could be considered.

MicroRNAs and Androgen Receptor: Emerging Players in Breast Cancer

Breast cancer (BC) is the most common cause of cancer among women, with a high incidence rate occurrence every year worldwide despite advances in its management. BC is characterized by a spectrum of subtypes which respond differently to treatments due to their biological features, representing the main issue in the control of this type of malignancy. Androgen receptor (AR) is emerging as a target to investigate among hormone receptors, since it seems to play a role at various stages of development of specific BC subsets. For this reason, in recent years AR has become very important in the clinical practice, although its role remains controversial. A number of studies have proposed a correlation between microRNAs (miRNAs), a class of gene expression modulators, and AR in prostate cancer (PC), but there are still few evidences about the relationship between miRNAs and AR in BC. The purpose of this review is to present a state of the art scenario with consideration to the most recent discoveries about miRNAs involved in the AR associated pathogenesis of BC, in order to provide new insights into the role of miRNAs as key drivers in the modulation of AR, and possible actors in the development and progression of BC. Moreover, we consider findings about involvement of AR signaling in all stages of BC, highlighting its association with different subsets of breast carcinomas and with pre- and postmenopausal state of patients.

Androgen receptor: A promising therapeutic target in breast cancer

Breast cancer (BCa) is the second most common cancer worldwide and the most prevalent cancer in women. The majority of BCa cases are positive (+) for the estrogen receptor (ER⁺, 80%) and progesterone receptor (PR⁺, 65%). Estrogen and progesterone hormones are known to be involved in cancer progression, and thus hormonal deprivation is used as an effective treatment for ER⁺PR⁺ BCa subtypes. However, some ER⁺PR⁺ BCa patients develop resistance to such therapies. Meanwhile, chemotherapy is the only available treatment for ER^-PR^- BCa tumors. Another hormone receptor known as the androgen receptor (AR) has also been found to be widely expressed in human breast carcinomas. However, the mechanisms of AR and its endogenous androgen ligands is not well-understood in BCa and its biological role in this hormone-related disease remains unclear. In this review, we aim to address the importance of the AR in BCa diagnosis and prognosis, current AR-targeting approaches in BCa, and the potential for AR-downstream molecules to serve as therapeutic targets.

Androgen receptor expression in circulating tumor cells of patients with metastatic breast cancer

The androgen receptor (AR) has potential clinical relevance in metastatic breast cancer (mBC) since it might be a treatment target and has been associated with endocrine resistance. A minimal-invasive way to determine AR expression on metastatic tumor cells is by characterization of circulating tumor cells (CTCs). Here, we assessed AR mRNA expression in CTCs (CTC-AR) and in matched primary tumor samples from mBC patients representing different breast cancer subtypes. In addition, we explored CTC-AR-status in relation to outcome on endocrine therapy. AR, and 92 AR or estrogen receptor (ER) related genes, were measured in CellSearch-enriched CTCs from 124 mBC patients and in 52 matched FFPE primary tissues using quantitative reverse-transcriptase PCR. AR in CTCs was considered positive if the expression was 1 standard deviation higher than the expression measured in 11 healthy blood donors. A total of 31% of the mBC patients had AR-positive (AR+) CTCs. 58% of the matched CTC and primary tumor samples were discordant with respect to AR status, observing both switches from AR+ to AR-negative (AR-) and vice versa. There was no statistically significant difference in progression-free survival for patients treated with ER-targeting drugs and CTC-AR-status (13 AR+/ 37 AR- cases, p = 0.28). Thus, AR can be determined in RNA isolated from CTCs, with in our set 31% AR-positive samples. Given the discordance between AR status in CTC samples and corresponding primary tumors, determination of AR expression in CTCs might be a promising tool to select mBC patients for AR inhibiting agents.

Non-canonical AR activity facilitates endocrine resistance in breast cancer

The role of androgen receptor (AR) in endocrine-resistant breast cancer is controversial and clinical trials targeting AR with an AR antagonist (e.g., enzalutamide) have been initiated. Here, we investigated the consequence of AR antagonism using in vitro and in vivo models of endocrine resistance. AR antagonism in MCF7-derived tamoxifen-resistant (TamR) and long-term estrogen-deprived breast cancer cell lines were achieved using siRNA-mediated knockdown or pharmacological inhibition with enzalutamide. The efficacy of enzalutamide was further assessed in vivo in an estrogen-independent endocrine-resistant patient-derived xenograft (PDX) model. Knockdown of AR inhibited the growth of the endocrine-resistant cell line models. Microarray gene expression profiling of the TamR cells following AR knockdown revealed perturbations in proliferative signaling pathways upregulated in endocrine resistance. AR loss also increased some canonical ER signaling events and restored sensitivity of TamR cells to tamoxifen. In contrast, enzalutamide did not recapitulate the effect of AR knockdown in vitro, even though it inhibited canonical AR signaling, which suggests that it is the non-canonical AR activity that facilitated endocrine resistance. Enzalutamide had demonstrable efficacy in inhibiting AR activity in vivo but did not affect the growth of the endocrine-resistant PDX model. Our findings implicate non-canonical AR activity in facilitating an endocrine-resistant phenotype in breast cancer. Unlike canonical AR signaling which is inhibited by enzalutamide, non-canonical AR activity is not effectively antagonized by enzalutamide, and this has important implications in the design of future AR-targeted clinical trials in endocrine-resistant breast cancer.

Androgen excess in breast cancer development: implications for prevention and treatment

The aim of this review is to highlight the pivotal role of androgen excess in the development of breast cancer. Available evidence suggests that testosterone controls breast epithelial growth through a balanced interaction between its two active metabolites: cell proliferation is promoted by estradiol while it is inhibited by dihydrotestosterone. A chronic overproduction of testosterone (e.g. ovarian stromal hyperplasia) results in an increased estrogen production and cell proliferation that are no longer counterbalanced by dihydrotestosterone. This shift in the androgen/estrogen balance partakes in the genesis of ER-positive tumors. The mammary gland is a modified apocrine gland, a fact rarely considered in breast carcinogenesis. When stimulated by androgens, apocrine cells synthesize epidermal growth factor (EGF) that triggers the ErbB family receptors. These include the EGF receptor and the human epithelial growth factor 2, both well known for stimulating cellular proliferation. As a result, an excessive production of androgens is capable of directly stimulating growth in apocrine and apocrine-like tumors, a subset of ER-negative/AR-positive tumors. The key role of androgen excess in the genesis of different subtypes of breast cancer has significant clinical implications for both treatment and prevention. Our belief stems from a thorough analysis of the literature, where an abundance of evidence is present to justify a clinical trial that would investigate the effectiveness of treating the underlying excessive androgen production.

Hormone signaling via androgen receptor affects breast cancer and prostate cancer in a male patient: A case report

Background

Male breast cancer (MBC) is rare, accounting for only around 1% of all breast cancers. Most MBCs are hormone-driven. Not only the estrogen receptor (ER), but also other steroid hormone receptors, including the androgen receptor (AR) and progesterone receptor (PgR) are expressed in MBC. AR activation in breast cancer cells facilitates downstream gene expression that drives tumorigenesis in a similar manner to ER. AR-mediated signalling works paradoxically in breast cancer and prostate cancer, and cancer cells expressing the AR are endocrine-sensitive.

Case presentation

We describe a case of double cancer of MBC and prostate cancer. A 69-year-old man was referred to our hospital with a lump in his left breast in the 1990s. The patient had cT3N3M0, stage IIIC breast cancer, and underwent a mastectomy and axillary lymph node dissection. Though adjuvant chemotherapy was administered, he experienced pleural metastasis 2 months after the surgery. Two years after the recurrence during endocrine therapy with oral 5-fluorouracil, he complained of frequent urination. Radiological and histological examinations revealed that the patient had cT3N0M0, stage III primary prostate cancer with a prostate-specific antigen (PSA) level of 40.5 ng/mL. Germline mutations in the BRCA1 and BRCA2 genes were not tested. He received multidisciplinary, continuous therapy for both breast and prostate cancer; however, 5 and 3 years after each diagnosis, respectively, he experienced a deep vein thrombosis in his right leg related to the endocrine therapy. Liver metastasis progressed after he stopped breast cancer therapy. However, long-term disease control had been achieved with anti-estrogen therapy for breast cancer and estrogen replacement therapy for prostate cancer.

Conclusions

Several studies have shown that estrogen exposure after estrogen depletion likely causes apoptosis of ER-positive breast cancer cells. Our findings indicate that this also applies to the environment in male body. AR dominant signaling prevents breast cancer recurrence and metastasis, especially in MBC patients.

Expression of hormone receptors, adipophilin, and GCDFP-15 in mucinous carcinoma of the skin

BACKGROUND

Primary cutaneous mucinous carcinoma (PCMC) is a rare epithelial tumor with unclear histogenesis.

METHODS

We evaluated the immunohistochemical expression of the estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR) in six cases of PCMC. The immunoreactivity of adipophilin and gross cystic disease fluid protein (GCDFP)-15 was investigated to determine the origin of the tumor.

RESULTS

The study included five males and one female aged 50 to 69 years who presented with a cutaneous mass in the face. Immunoreactivity for ER, PR, and AR was observed in all cases, and all cases were negative for adipophilin but positive for GCDFP-15.

CONCLUSIONS

This report is the first to show AR expression in PCMC. All of followed cases manifested indolent clinical course, and the prognostic significance of hormone receptors in PCMC remains unclear. The negative immunoreactivity of PCMC for adipophilin and positivity for GCDFP-15 suggests a more likely relationship to apocrine than to sebaceous glands.

Harnessing Androgen Receptor Pathway Activation for Targeted Alpha Particle Radioimmunotherapy of Breast Cancer

PURPOSE

The impact of androgen receptor (AR) activity in breast cancer biology is unclear. We characterized and tested a novel therapy to an AR-governed target in breast cancer.Experimental Design: We evaluated the expression of prototypical AR gene products human kallikrein 2 (hK2) and PSA in breast cancer models. We screened 13 well-characterized breast cancer cell lines for hK2 and PSA production upon in vitro hormone stimulation by testosterone [dihydrotestosterone (DHT)]. AR-positive lines were further evaluated by exposure to estrogen (17β-Estradiol) and the synthetic progestin D-Norgestrel. We then evaluated an anti-hK2-targeted radiotherapy platform (hu11B6), labeled with alpha (α)-particle emitting Actinium-225, to specifically treat AR-expressing breast cancer xenografts under hormone stimulation.

RESULTS

D-Norgestrel and DHT activated the AR pathway, while 17β-Estradiol did not. Competitive binding for AR protein showed similar affinity between DHT and D-Norgestrel, indicating direct AR-ligand interaction. In vivo production of hK2 was sufficient to achieve site-specific delivery of therapeutic radionuclide to tumor tissue at >20-fold over background muscle uptake; effecting long-term local tumor control.

CONCLUSIONS

[²²⁵Ac]hu11B6 targeted radiotherapy was potentiated by DHT and by D-Norgestrel in murine xenograft models of breast cancer. AR activity in breast cancer correlates with kallikrein-related peptidase-2 and can be activated by D-Norgestrel, a common contraceptive, and AR induction can be harnessed for hK2-targeted breast cancer α-emitter radiotherapy.

Abiraterone shows alternate activity in models of endocrine resistant and sensitive disease

BACKGROUND

Resistance to endocrine therapy remains a major clinical problem in the treatment of oestrogen-receptor positive (ER+) breast cancer. Studies show androgen-receptor (AR) remains present in 80-90% of metastatic breast cancers providing support for blockade of AR-signalling. However, clinical studies with abiraterone, which blocks cytochrome P450 17A1 (CYP17A1) showed limited benefit.

METHODS

In order to address this, we assessed the impact of abiraterone on cell-viability, cell-death, ER-mediated transactivation and recruitment to target promoters. together with ligand-binding assays in a panel of ER+ breast cancer cell lines that were either oestrogen-dependent, modelling endocrine-sensitive disease, or oestrogen-independent modelling relapse on an aromatase inhibitor. The latter, harboured wild-type (wt) or naturally occurring ESR1 mutations.

RESULTS

Similar to oestrogen, abiraterone showed paradoxical impact on proliferation by stimulating cell growth or death, depending on whether the cells are hormone-dependent or have undergone prolonged oestrogen-deprivation, respectively. Abiraterone increased ER-turnover, induced ER-mediated transactivation and ER-degradation via the proteasome.

CONCLUSIONS

Our study confirms the oestrogenic activity of abiraterone and highlights its differential impact on cells dependent on oestrogen for their proliferation vs. those that are ligand-independent and harbour wt or mutant ESR1. These properties could impact the clinical efficacy of abiraterone in breast cancer.

Ethanolic Extracts from Azadirachta indica Leaves Modulate Transcriptional Levels of Hormone Receptor Variant in Breast Cancer Cell Lines

Breast Cancer (BC) encompasses numerous entities with different biological and behavioral characteristics, favored by tumor molecular complexity. Azadirachta indica (neem) presents phenolic compounds, indicating its potential as an antineoplastic compound. The present study aimed to evaluate the cellular response of MCF10, MCF7, and MDA-MB-231 breast cell lines to ethanolic extracts of neem leaves (EENL) obtained by dichloromethane (DCM) and ethyl acetate (EA) solvent. Extracts’ antiproliferative activities were evaluated against MCF 10A, MCF7, and MDA-MB-231 for 24 and 48 h using MTT assay. ESR1, ESR2, AR, AR-V1, AR-V4, and AR-V7 transcripts were quantified through qPCR for 0.03125 μg/mL of DCM and 1.0 μg/mL for EA for 48 h. The EENL was tested on Drosophila melanogaster as a sole treatment and then also together with doxorubicin. Antiproliferative effect on tumor cell lines without affecting MCF 10A were 1.0 µg/mL (P < 0.001) for EA, and 0.03125 µg/mL (P < 0.0001) for DCM, both after 48 h. Transcriptional levels of AR-V7 increased after treatment. In vivo assays demonstrated that EENL induced fewer tumors at a higher concentration with doxorubicin (DXR). The behavior of AR-V7 in the MDA-MB-231 tumor lineage indicates new pathways involved in tumor biology and this may have therapeutic value for cancer.

Clinical significance of androgen receptor expression in triple negative breast cancer-an immunohistochemistry study

Androgen receptor (AR) is closely associated with the occurrence and progression of breast cancer; however, the clinical significance of it in triple negative breast cancer (TNBC) has been controversial. There is a limited amount of research regarding the effect of neoadjuvant chemotherapy on AR expression. By examining the expression of AR in patients with TNBC, the aim of the present study is to explore the clinical significance of AR and provide evidence for AR-directed treatment in TNBC. A total of 188 patients with primary TNBC with complete medical records were included in this retrospective study. Tumor sections from 41 patients (21.8%) were positive for AR, which was more often detected in small tumors (P=0.042) and cases with no lymph node involvement (P=0.032). Among them, 102 were treated with neoadjuvant chemotherapy (NAC). A total of 17 patients (16.7%) exhibited pathological complete response. However, the patient response was irrelevant to AR expression. Matched pathological tissues before and after NAC were collected for 49 cases, suggesting an enrichment of AR-expressing tumors following chemotherapy (P=0.008). Further analysis indicated that AR expression had no correlation with the disease-free and overall survival of patients with general TNBC; rather, it predicted a poor survival of the patients with stage III TNBC in comparison with those at earlier stages (P=0.035). AR expression occurs more often in small TNBC tumors or in cases with no lymph node metastasis. It is associated with a poor prognosis of the patients with advanced stages of tumors.

The interplay of endocrine therapy, steroid pathways and therapeutic resistance: Importance of androgen in breast carcinoma

A great majority of breast carcinomas expresses estrogen receptor (ER) and estrogens have crucial roles in the progress of breast carcinomas. Endocrine therapy targeting ER and/or intratumoral estrogen production significantly improved clinical outcomes of the patients with ER-positive breast carcinomas. However, resistance to endocrine therapy is often observed and significant number of patients will recur after the treatment. In addition, treatment for the patients with triple-negative breast carcinomas (negative for all ER, progesterone receptor (PR) and HER2) are limited to cytotoxic chemotherapy and novel therapeutic targets need to be identified. In breast carcinoma tissues, not only ER but androgen receptor (AR) is frequently expressed, suggesting pivotal roles of androgens in the progress of breast carcinomas. Growing interest on androgen action as possible therapeutic target has been taken, but androgen action seems quite complicated in breast carcinomas and inconsistent findings has been also proposed. In this review, we will summarize recent studies regarding intratumoral androgen production and its regulation as well as distinct subset of breast carcinomas characterized by activated AR signaling and recent clinical trial targeting AR in the patients with either ER-positive and ER-negative breast carcinomas.

Acquired resistance to aromatase inhibitors: where we stand!

Aromatase inhibitors (AIs) are one of the principal therapeutic approaches for estrogen receptor-positive (ER⁺) breast cancer in postmenopausal women. They block estrogen biosynthesis through aromatase inhibition, thus preventing tumour progression. Besides the therapeutic success of the third-generation AIs, acquired resistance may develop, leading to tumour relapse. This resistance is thought to be the result of a change in the behaviour of ER in these breast cancer cells, presumably by PI3K/AKT pathway enhancement along with alterations in other signalling pathways. Nevertheless, biological mechanisms, such as apoptosis, autophagy, cell cycle modulation and activation of androgen receptor (AR), are also implicated in acquired resistance. Moreover, clinical evidence demonstrated that there is a lack of cross-resistance among AIs, although the reason is not fully understood. Thus, there is a demand to understand the mechanisms involved in endocrine resistance to each AI, since the search for new strategies to surpass breast cancer acquired resistance is of major concern.

Androgens and endometrium: New insights and new targets

Androgens are synthesised in both the ovary and adrenals in women and play an important role in the regulation of female fertility, as well as in the aetiology of disorders such as polycystic ovarian syndrome, endometriosis and endometrial cancer. The endometrium is an androgen target tissue and the impact of AR-mediated effects has been studied using human endometrial tissue samples and rodent models. In this review we highlight recent evidence that endometrial androgen biosynthesis and intracrine action is important in preparation of a tissue microenvironment that can support implantation and establishment of pregnancy. The impact of androgens on endometrial cell proliferation, in repair of the endometrial wound at the time of menstruation and in endometrial disorders is discussed. Future directions for research focused on AR function as a therapeutic target are considered.

Phosphorylation of androgen receptors at serine 515 is a potential prognostic marker for triple negative breast cancer

1.7 million cases of breast cancer are diagnosed every year with 522,000 deaths. Molecular classifications of breast cancer have resulted in improved treatments. However, treatments for triple negative breast cancer (TNBC) are lacking. Analysis of molecular targets for TNBC is a priority. One potential candidate is androgen receptor (AR) phosphorylation. This study assessed the role of AR phosphorylation at ser81/ser515 and their two upstream effectors, cyclin-dependent kinase 1 (pCDK1) and extracellular-regulated kinase 1/2 (pERK1/2) in 332 ductal breast cancer patients by immunohistochemistry.

pERK1/2 combined with AR-515 associated with improved cancer-specific survival (CSS, p = 0.038), decreased size (p = 0.001), invasive grade (p < 0.001), necrosis (p = 0.003), b-lymphocytes (p = 0.020), molecular subtype (p < 0.001) and estrogen receptor (ER)/progesterone receptor (PR)-status (p < 0.001). The cohort was therefore stratified into ER+ve and ER-ve patients. In ER+ve tumours, pERK1/2 combined with AR-515 associated with improved CSS (p = 0.038), smaller size (p = 0.004), invasive grade (p = 0.001), decreased b-lymphocytes (p = 0.013) and increased plasma cells (p = 0.048). In contrast, in TNBC patients, phosphorylation of AR-515 associated with poorer CSS (p = 0.007). pERK1/2 combined with AR-515 associated with decreased inflammation (p = 0.003), increased tumour stroma (p = 0.003) and tumour budding (p = 0.011), with trends towards decrease CSS (p = 0.065) and macrophage levels (p = 0.093).

In Conclusions, AR-515 may be an important regulator of inflammation in breast cancer potential via ERK1/2 phosphorylation. AR-515 is a potential prognostic marker and therapeutic target for TNBC.