Endothelial dysfunction in breast cancer survivors on aromatase inhibitors: changes over time

BACKGROUND

Breast cancer is estimated to comprise about 290,560 new cases in 2022. Aromatase inhibitors (AIs) are recommended as adjuvant treatment for estrogen-receptor positive (ER+) breast carcinoma in postmenopausal women, which includes approximately two-thirds of all women with breast cancer. AIs inhibit the peripheral conversion of androgens to estrogen by deactivation of the aromatase enzyme, leading to a reduction in serum estrogen level in postmenopausal women with ER+ breast carcinoma. Estrogen is known for its cardiovascular (CV) protective properties through a variety of mechanisms including vasodilation of blood vessels and inhibition of vascular injury resulting in the prevention of atherosclerosis. In clinical trials and prospective cohorts, the long-term use of AIs can increase the risk for hypertension and hyperlipidemia. Studies demonstrate mixed results as to the impact of AIs on actual CV events and overall survival.

METHODS

A single arm longitudinal study of 14 postmenopausal women with ER+ breast cancer prescribed adjuvant AIs at the University of Minnesota (UMN). Subjects with a history of known tobacco use, hypertension, hyperlipidemia, and diabetes were excluded to eliminate potential confounding factors. Participants underwent routine labs, blood pressure assessments, and vascular testing at baseline (prior to starting AIs) and at six months. Vascular assessment was performed using the EndoPAT 2000 and HDI/PulseWave CR-2000 Cardiovascular Profiling System and pulse contour analysis on two occasions as previously described. Vascular measurements were conducted by one trained vascular technician. Assessments were performed in triplicate, and the mean indices were used for analyses. All subjects were on an AI at the follow-up visit. The protocol was approved by the UMN Institutional Review Board and all participants were provided written informed consent. Baseline and follow-up characteristics were compared using Wilcoxon signed-rank tests. Analyses were performed using R version 3.6.1 (R Foundation for Statistical Computing, Vienna, Austria).

RESULTS

After six months of AI treatment, EndoPAT® ratio declined to a median 1.12 (Q1: 0.85, Q3: 1.86; p = 0.045; Figure 1) and median estradiol levels decreased to 2 pg/mL (Q1: 2, Q3: 3; p=0.052). There was no evidence of association between change in EndoPAT® and change in estradiol level (p = 0.91). There were no statistically significant changes in small or large arterial elasticity.

CONCLUSIONS

We hypothesize that long-term use of AI can lead to persistent endothelial dysfunction, and further investigation is necessary. In our study, patients were on AI for approximately 5-10 years. As a result, we do not have data on whether these changes, such as EndoPAT® ratio and the elasticity of small and large arterial, are reversible with discontinuation of AI. These findings set the stage for a larger study to more conclusively determine the association between AI exposure and cardiovascular outcomes. Further studies should evaluate for multivariate associations withmodifiable risk factors for CV disease.

Cardiovascular toxicities associated with bispecific T-cell engager therapy

BACKGROUND

Bispecific T-cell engagers (BTEs) are novel agents used to treat hematological malignancies. Early trials were underpowered to define cardiovascular adverse events (CVAE) and no large-scale studies systematically examined the CVAEs associated with BTEs.

METHODS

Leveraging the US Food and Drug Administration's Adverse Event Reporting System-(FAERS), we identified the relative frequency of CVAEs after initiation of five BTE products approved by the Food and Drug Administration between 2014 and 2023 for the treatment of hematological malignancies. Adjusted reporting ORs (aROR) were used to identify disproportionate reporting of CVAEs with BTEs compared with background rates in the database. Fatality rates and risk ratios (RRs) for each adverse event (AE) were calculated.

RESULTS

From 3668 BTE-related cases reported to FAERS, 747 (20.4%) involved CVAEs. BTEs as a class were associated with fatal CVAEs (aROR 1.29 (95% CI 1.12 to 1.50)), an association mainly driven by teclistamab (aROR 2.44 (95% CI 1.65 to 3.60)). Teclistamab was also associated with a disproportionate risk of myocarditis (aROR 25.70 (95% CI 9.54 to 69.23)) and shock (aROR 3.63 (95% CI 2.30 to 5.74)), whereas blinatumomab was associated with a disproportionate risk of disseminated intravascular coagulation (aROR 3.02 (95% CI 1.98 to 4.60)) and hypotension (aROR 1.59 (95% CI 1.25 to 2.03)). CVAEs were more fatal compared with non-CVAEs (31.1% vs 17.4%; RR 1.76 (95% CI 1.54 to 2.03)). Most CVAEs (83.3%) did not overlap with cytokine release syndrome.

CONCLUSION

In the first postmarketing surveillance study of BTEs, CVAEs were involved in approximately one in five AE reports and carried a significant mortality risk.

Cardiovascular Toxicities of BTK Inhibitors in Chronic Lymphocytic Leukemia: JACC: CardioOncology State-of-the-Art Review

Over the past decade, the treatment landscape of chronic lymphocytic leukemia (CLL) has dramatically changed, shifting from cytotoxic chemotherapy to targeted therapies. Bruton's tyrosine kinase (BTK) inhibitors have revolutionized the treatment of CLL and are increasingly applied in many other malignancies. However, ibrutinib, the first BTK inhibitor approved, is associated with serious toxicities, including atrial fibrillation in up to 38% of patients, ventricular arrhythmias, and other cardiovascular toxicities. Emerging data suggest several newer BTK inhibitors (eg, acalabrutinib, zanubrutinib) are still associated with cardiotoxic risks. This review examines the current state of evidence, including incidence rates, risk factors, mechanisms, and management strategies of cardiovascular toxicities with BTK inhibitors and other CLL therapies. We specifically focus on atrial fibrillation, ventricular arrhythmias/sudden death, hypertension, heart failure, bleeding, and stroke. We also touch on other emerging BTK therapies (eg, pirtobrutinib). Finally, we highlight key unanswered questions and future directions of research.

Direct current cardioversion practices following percutaneous left atrial appendage closure

INTRODUCTION

Among patients with non-valvular atrial fibrillation (AF) and percutaneous left atrial appendage closure (LAAC) undergoing direct current cardioversion (DCCV), the need for and use of LAA imaging and oral anticoagulation (OAC) is unclear.

OBJECTIVE

The purpose of this study is to evaluate the real-world use of transesophageal echocardiography (TEE) or cardiac computed tomography angiography (CCTA) before DCCV and use of OAC pre- and post-DCCV in patients with AF status post percutaneous LAAC.

METHODS

This retrospective single center study included all patients who underwent DCCV after percutaneous LAAC from 2016 to 2022. Key measures were completion of TEE or CCTA pre-DCCV, OAC use pre- and post-DCCV, incidence of left atrial thrombus (LAT) or device-related thrombus (DRT), incidence of peri-device leak (PDL), and DCCV-related complications (stroke, systemic embolism, device embolization, major bleeding, or death) within 30 days.

RESULTS

A total of 76 patients with AF and LAAC underwent 122 cases of DCCV. LAAC consisted of 47 (62%), 28 (37%), and 1 (1%) case of Watchman 2.5, Watchman FLX, and Lariat, respectively. Among the 122 DCCV cases, 31 (25%) cases were identified as "non-guideline based" due to: (1) no OAC for 3 weeks and no LAA imaging within 48 h before DCCV in 12 (10%) cases, (2) no OAC for 4 weeks following DCCV in 16 (13%) cases, or (3) both in 3 (2%) cases. Among the 70 (57%) cases that underwent TEE or CCTA before DCCV, 16 (23%) cases had a PDL with a mean size of 3.0 ± 1.1 mm, and 4 (6%) cases had a LAT/DRT on TEE resulting in cancellation. There were no DCCV-related complications within 30 days.

DISCUSSION

There is a widely varied practice pattern of TEE, CCTA, and OAC use with DCCV after LAAC, with a 6% rate of LAT/DRT. LAA imaging before DCCV appears prudent in all cases, especially within 1 year of LAAC, to assess for device position, PDL, and LAT/DRT.

Oxytocin versus a combination of tranexamic acid and ethamsylate in reducing intraoperative bleeding during abdominal myomectomy: a randomized clinical trial

OBJECTIVE

Myomectomy is the preferred surgical approach to manage uterine fibroids. However, uterine fibroids are highly vascular tumors and, consequently, extremely susceptible to problems from myomectomy-related hemorrhage. Hence, we aim to compare oxytocin efficacy and safety profile versus tranexamic acid (TA) with ethamsylate for reducing bleeding during myomectomy.

METHODS

This randomized, double-blinded multicenter study was performed between 20th August 2020 and 20th October 2020 at El-Galaa Teaching Hospital, El Hussein University Hospital, Al-Azhar University Hospitals of Assiut, and Al-Azhar University Hospitals of Damietta. One hundred and eighty patients were enrolled and divided into three groups: group (1) received an injection of 30 IU of oxytocin in 500 ml of normal saline; group (2) received injections of 1 g of TA, 250 mg of Ethamsylate, and 110 ml of normal saline IV; and group (3) received an injection of 110 ml of normal saline IV just before surgical incision.

RESULTS

In 180 premenopausal women, oxytocin and TA with ethamsylate had no significant value in lowering intraoperative blood loss compared with the placebo for abdominal myomectomy (666.25 ± 183.03, 630.72 ± 145.83, and 646.67 ± 168.92, respectively (P = 0.506)). Non-significant trends were observed for a reduction in operation time (P = 0.760), intra/postoperative blood transfusion (P = 0.624), hospital stay (P = 0.986), postoperative fever (P = 0.659), and wound infection (P = 1).

CONCLUSION

Oxytocin and TA with ethamsylate had no significant value in lowering intraoperative blood loss compared with the placebo for abdominal myomectomy which opens a new question about the role of the use of the hemostatic drug during myomectomy especially in centers with limited resources and had higher rates.

TRIAL REGISTRATION

The study was registered on Pan African Clinical Trials Registry with the following number: PACTR202008739887429 and was approved on 24/08/2020.

Endothelial Dysfunction in Breast Cancer Survivors on Aromatase Inhibitors: Changes over Time

Background

Aromatase inhibitors (AIs) are recommended as adjuvant treatment for estrogen-receptor positive breast carcinoma in postmenopausal women. Studies demonstrate mixed results as to the impact of AIs on cardiovascular (CV) events and overall survival. With the increasing number of pre- and postmenopausal women on AIs for five to ten years, understanding the long-term impact of AIs on blood vessels and CV risk in cancer survivors is vital.

Methods

A single arm longitudinal study of 14 postmenopausal women with ER+ breast cancer prescribed adjuvant AIs at the University of Minnesota. Subjects with a history of tobacco use, hypertension, or hyperlipidemia were excluded. Participants underwent routine labs, blood pressure assessments, and vascular testing at baseline (prior to starting AIs) and at six months. Vascular assessment was performed using the EndoPAT 2000 and HDI/PulseWave CR-2000 Cardiovascular Pro ling System and pulse contour analysis on two occasions as previously described. Vascular measurements were conducted by one trained vascular technician. Assessments were performed in triplicate, and the mean indices were used for analyses. All subjects were on an AI at the follow-up visit. The protocol was approved by the UMN Institutional Review Board and all participants were provided written informed consent. Baseline and follow-up characteristics were compared using Wilcoxon signed-rank tests. Analyses were performed using R version 3.6.1 (R Foundation for Statistical Computing, Vienna, Austria).

Results

After six months of AI treatment, EndoPAT® ratio declined to a median 1.12 (Q1: 0.85, Q3: 1.86; p=0.045) and median estradiol levels decreased to 2 pg/mL (Q1: 2, Q3: 3; p=0.052). There was no evidence of association between change in EndoPAT® and change in estradiol level (p=0.91). There were no statistically significant changes in small or large arterial elasticity.

Conclusion

Endovascular dysfunction is an early sign for atherosclerosis and vascular impairment. This study suggests that postmenopausal breast cancer survivors on aromatase inhibitor therapy develop endothelial dysfunction as early as six months which is a predictor of adverse CV disease. We hypothesize that long-term use of AIs can lead to persistent endothelial dysfunction. It is unclear if these changes are reversible once AI use is discontinued and further investigation is necessary.

Sudden Onset Iron Overload Cardiomyopathy After Liver Transplantation

Iron overload cardiomyopathy has been described in patients who develop acute heart failure after liver transplantation but few reports of this are available. We present a case of a patient with end-stage liver disease who underwent a deceased donor liver transplantation and developed acute onset systolic heart failure with reduced left ventricular ejection fraction. A cardiac magnetic resonance image demonstrated late gadolinium enhancement with diffuse enhancement globally and T1 mapping with severely decreased pre-contrast T1 values suggesting iron overload cardiomyopathy. The patient was treated with iron chelating therapy as well as heart failure guideline-directed medical therapy with subsequent improvement in cardiac function on follow-up magnetic resonance images. Despite our patient's diagnosis of iron overload cardiomyopathy, her iron studies showed normal serum iron and ferritin levels and no evidence of hepatic iron deposition in the transplanted liver.

Case of Primary Hepatic Angiosarcoma Presenting With Jaundice and Infiltrative Liver Masses

Primary hepatic angiosarcoma (PHA) is a rare and aggressive mesenchymal liver tumor with a poor prognosis and high mortality. Treatment options are limited to palliative chemotherapy with surgical resection reserved for the few cases that present early. We present a case of a patient who presented with jaundice and elevated liver enzymes. Imaging identified a diffusely heterogeneous liver consistent with cirrhosis, findings of portal hypertension, and 2 ill-defined liver lesions. Biopsy results confirmed PHA. Primary hepatic angiosarcoma does not have a typical presentation but should be considered for any patient presenting with an infiltrative liver mass.

Presentation and Outcomes of Hepatocellular Carcinoma in the Arabian Peninsula: A Review of a Single Institution Experience in the Sorafenib Era

PURPOSE

There is a growing evidence showing that there are geographic differences in hepatocellular carcinoma (HCC). Little is known about the characteristics of hepatocellular carcinoma in the Arabian Peninsula. The present study examines the presentation and outcomes of HCC in a single institution.

METHODS

A retrospective chart review of patients presented with advanced-stage HCC to Kuwait Cancer Control Center (KCCC) between 2008 and 2018 was conducted. Data collected included patients demographics, HCC risk factors, performance status, Child-Pugh score, pick up of sorafenib, and survival.

RESULTS

About 111 cases were analyzed. The mean age of the cohort was 61.8 ± 11.4 years and 94 patients (84.7%) were males. HCV and diabetes were the most common risk factors for HCC and presented in 60 patients (54.1%) and 45 patients (40.5%), respectively. About 78 (70.3%) patients had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1 at presentation. Only 29 (26.1%) patients presented with Child-Pugh class A, while 42 (40.4%) patients received sorafenib. The median overall survival was only 3 months.

CONCLUSIONS

In our cohort, HCV and diabetes were the main risk factors for HCC. The majority of patients was not amenable to sorafenib treatment and carries a very poor prognosis.

Does the Time of Starting Progesterone Luteal Support Affect Embryo Transfer in Long Agonist Protocol Downregulated ICSI Cycles? A Randomized Controlled Trial

The aim of this study was to compare the effects of starting progesterone (P4) luteal support (LS) on day of egg retrieval (ER) or day of embryo transfer (ET) on the ratio of difficult ET and cycle outcome. This was a RCT ( ClinicalTrials.gov Identifier: NCT03040830) carried out at Mansoura Integrated Fertility Center (MIFC), Mansoura, Egypt, from November 2015 to January 2017. A total of 171 eligible long agonist ICSI cases were randomly allocated on day of ER into group A (86) starting LS as daily IM 100 mg P4 on day of ER and group B (85) starting P4-LS on day of ET. Difficult ET was defined as blood on ET catheter and/or sounding or dilating the cervix. Primary outcome was the overall ratio of difficult ET and ratios on day 3 and 5 ET. Secondary outcome was the ongoing pregnancy rate (OPR) and implantation rate (IR). The results are presented as % for groups A and B respectively: overall difficult ET (44.1, 24.7) (p = 0.009); day 3 difficult ET (23.2, 24.4) (p = 0.45); day 5 difficult ET (62.7, 25.6) (p = 0.001); overall OPR (38.3, 44.7) (p = 0.43); day 3 ET OPR (41.8, 33.3) (p = 0.51); day 5 ET OPR (34.8, 57.5) (p = 0.048); overall IR (20.0, 22.5) (p = 0.62); day 3 ET IR (17.8, 13.4) (p = 0.44); day 5 ET IR (22, 34.1) (p = 0.09). In conclusion, starting P4 luteal support on egg retrieval day is associated with significantly higher ratio of difficult embryo transfer and lower ongoing pregnancy rate and tendency to lower IR in day 5 ET, so starting P4-LS on day of ET is recommended.

Decreased Renal Function is Associated with Heart Failure Readmissions

Introduction Heart failure (HF) is one of the most common causes of hospitalization and readmissions. Approximately six million Americans are living with HF. Among patients with HF, hospitalization rate in the United States is higher for those over age 65, making it one of the leading causes of hospitalization in this age group. Furthermore, about 15% of those who were hospitalized with HF were readmitted within 30 days and 30% within 60 days. HF and chronic kidney disease (CKD) share many risk factors; therefore, it is expected that CKD is more prevalent in HF. About 50% of patients with HF also have concomitant CKD. Those patients have been found to have an increased risk of mortality and morbidity. This risk increases as glomerular filtration rate (GFR) decreases. Strategies to reduce the hospitalization rate in patients with HF include optimizing evidence-based drug and device therapies, addressing the causes of HF, treating comorbidities, and improving management of care. In our study, we aim to find an association between HF and the patient's renal function as well as the GFR level. This study investigates the effect of renal function on HF morbidity and readmission rate. Methods We performed a retrospective study looking at 132 patients who were admitted to the hospital with HF and compared their measured GFR at three key time periods: admissions, discharges, and readmissions at 30 days. A Pearson product-moment correlation coefficient was calculated to determine the association between the GFR and readmission in HF admission cases. Results There is a statistically significant difference in the readmission rate based on the change in GFR between admission and discharge (Admit GFR - Discharge GFR; t = 2.28; p < 0.05). We found that patients who were readmitted in 30 days had an average decrease in GFR by 2.46 ml/min/1.73 m2, whereas patients with a lower readmission rate had an average increase in GFR by 1.92 ml/min/1.73 m2. Conclusion A decline in renal function due to hospitalization in patients with renal failure is associated with an increase in readmission for HF. Providers should be cognizant of the need to optimize renal function as well as cardiac function during hospitalization.

Abstract P4-09-05: Withdrawn

This abstract was withdrawn by the authors.

Evaluation of applying IHC4 as a prognostic model in the translational study of Intergroup Exemestane Study (IES): PathIES

BACKGROUND

Intergroup Exemestane Study (IES) was a randomised study that showed a survival benefit of switching adjuvant endocrine therapy after 2-3 years from tamoxifen to exemestane. This PathIES aimed to assess the role of immunohistochemical (IHC)4 score in determining the relative sensitivity to either tamoxifen or sequential treatment with tamoxifen and exemestane.

PATIENTS AND METHODS

Primary tumour samples were available for 1274 patients (27% of IES population). Only patients for whom the IHC4 score could be calculated (based on oestrogen receptor, progesterone receptor, HER2 and Ki67) were included in this analysis (N = 430 patients). The clinical score (C) was based on age, grade, tumour size and nodal status. The association of clinicopathological parameters, IHC4(+C) scores and treatment effect with time to distant recurrence-free survival (TTDR) was assessed in univariable and multivariable Cox regression analyses. A modified clinical score (PathIEscore) (N = 350) was also estimated.

RESULTS

Our results confirm the prognostic importance of the original IHC4, alone and in conjunction with clinical scores, but no significant difference with treatment effects was observed. The combined IHC4 + Clinical PathIES score was prognostic for TTDR (P < 0.001) with a hazard ratio (HR) of 5.54 (95% CI 1.29-23.70) for a change from 1st quartile (Q1) to Q1-Q3 and HR of 15.54 (95% CI 3.70-65.24) for a change from Q1 to Q4.

CONCLUSION

In the PathIES population, the IHC4 score is useful in predicting long-term relapse in patients who remain disease-free after 2-3 years. This is a first trial to suggest the extending use of IHC4+C score for prognostic indication for patients who have switched endocrine therapies at 2-3 years and who remain disease-free after 2-3 years.

Imaging features of haematological malignancies of kidneys

Haematological malignancies are relatively uncommon neoplasms of kidneys. Nevertheless, the incidence of these neoplasms is increasing, partly due to more widespread use of computed tomography and magnetic resonance imaging. This article discusses the clinical and imaging features of renal lymphoma, leukaemia, extra-osseous multiple myeloma, and post-transplant lymphoproliferative disorder. Although there is overlap of imaging features with other more common malignancies, such as transitional and renal cell cancers, the combination of imaging findings and the appropriate clinical picture should allow the radiologist to raise a provisional diagnosis of a haematological neoplasm. This has management implications including the preference for image-guided core biopsies and a shift towards medical rather than surgical therapy.

Self-healing dynamic bond-based rubbers: understanding the mechanisms in ionomeric elastomer model systems

Systematic structure-property investigations on the time-dependent mechanical properties of an ionomer model system with variation of the ionic fraction and the counter ion as obtained from SAXS, dynamic oscillatory rheology and tensile tests, deliver the prerequisites and tools for property adjustment and optimization of their self-healing efficiency.

Abstract P2-02-01: Did established clinical practice regarding MRI bias the COMICE trial?

Introduction: The negative COMICE study and reports of inappropriate mastectomies worldwide have served to discredit the use of preoperative MRI for the purpose of aiding conservative breast surgery. We postulate that established clinical practice regarding MRI at the time of the COMICE trial lead to bias in case selection, with more complicated cases being preselected out prior to randomisation. We reviewed the local practice at the time of COMICE.

Methods and materials: Retrospective analysis of all cases of Breast MRI performed to assess disease extent pre-operatively during recruitment to COMICE (December 2001 - January 2007) was undertaken. Size on mammogram/ultrasound, MRI and histology was documented. As pre-PAC's era, the information was obtained from imaging and pathology reports. Where reports did not include distance between lesions in multifocal/multicentric disease, the sum of the lesions was used (taken as immediately adjacent) so as not to overestimate the size. All cases were reviewed blinded to COMICE status. Cases with mammogram/ultrasound size &gt;/ = 40mm were excluded as these were deemed unsuitable for conservative surgery.

Results: A total of 318 breast MRI examinations were performed in this interval to assess disease extent pre-operatively of which, 81 were excluded appropriately, for inadequate information (n = 47), size on conventional imaging &gt;/ = 40mm (n = 18), receiving neo-adjuvant treatment (n = 6), non cancer diagnosis (n = 7) and non invasive disease (n = 3). 242 cancers from 237 patients were included comprising 77COMICE and 160NON-COMICE patients. Statistical difference was noted in the types of surgery between the groups, p&lt;0.001. Re-excision rates were similar: COMICE = 11.7% and NON-COMICE = 8%. Mastectomy rates were however different, 15.6% of the COMICE group and 42% of the NON-COMICE group.

There was a significant difference in histological size between the 2 groups, mean size in NON-COMICE cases 32mm versus 26mm in the COMICE group (p = 0.009). There was a significant difference in the tumour types between the 2 groups (p&lt;0.001). Notably 37% of cases in the NON-COMICE group were of lobular type compared to 13% of the COMICE group.

Conclusion: Data from this well established MRI unit has demonstrated clinical bias in the COMICE trial with more complicated cases, which benefited from MRI, being pre-selected out prior to randomisation which understated the value of MRI. MRI in appropriately selected patients in conjunction with modern oncoplastic surgical techniques will increase the opportunities for conservative surgery rather than increase mastectomy rates. An aggressive biopsy policy for MRI detected lesions is required to avoid inappropriate mastectomies.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-02-01.

P3-04-01: Molecular Characterization of African Breast Cancer; Results from a Large Tissue Microarray Study

Introduction: Breast cancer in African women has been understudied for decades. Evidence derived mainly from studies on African-American women, supports that tumours of black women are biologically different and more aggressive than those occurring in the white population. Of the 4 main taxonomic groups of breast cancer, basal tumours are more represented in those women. In the present state of knowledge, very little is known about the biology and molecular profile of breast cancer in Africa. The aim of this study was to test the hypothesis that the molecular profile of African breast cancer is distinct from its Western counterpart. This was achieved by collecting a large cohort of breast carcinomas from an indigenous African population for phenotypical characterization and testing for expression of potential predictive and prognostic markers.

Methods: Breast tumours were collected via collaboration with five centres in Nigeria (the most populous country in Africa) and assembled into tissue microarrays (TMAs). All tumours were reviewed by a specialist breast pathologist following the Royal College of Pathologists (RCPath) guidelines to confirm diagnosis, type, grade and nodal status. Patients age, tumour size and clinical data, where available, were collected from the original pathology reports and case notes. Representative tumour areas were selected and marked for TMA construction. TMA sections were stained for a range of markers including hormone receptors (ERα, ERβ, PR, AR), cyclin D, HER2, Ki67, bcl2, basal (CK5/6, CK14) and luminal cytokeratins (CK18, 19).

Results: A total of 830 tumours were assembled into TMAs. The mean age at diagnosis was 47.69yrs with 58% of patients presenting under the age of 50. Only 8.5% of tumours were of grade 1. Most tumours (87%) were of ductal no special type, followed by lobular and metaplastic carcinomas. The majority of the tumours were ERα, PR and HER2 negative (77%, 80% and 81% respectively). The triple negative tumours were the predominant phenotype (55.6%). Luminal A type tumours comprised 24.3% followed by the HER2 positive (13.9%) and luminal B tumours (6.2%). The differences of all those parameters were statistically highly significant (p&lt;0.001). Most tumours expressed ERß including 75% of those that were ERα/PR negative. A large proportion of the tumours (22%) were of the basal phenotype of which two thirds were also triple negative. Over half of the triple negative tumours were also node positive.

Hierarchal cluster analysis showed the basal tumours dendrogram to comprise two groups; one showing clustering of ***ERα/PR/HER2 and the second showing clustering of ERß with CK5 and CK14.

Conclusion: To our knowledge, this is largest and most comprehensive study of African breast cancer to date. Our data confirms the hypothesis that African breast cancer is biologically distinct and shows remarkable differences in histological type, grade, hormone receptors & HER2 status when compared with breast cancer in white women. The early age at presentation, predominance of high grade and triple negative, but not necessarily basal phenotype, may explain the poor prognosis and requires tailoring treatment strategies to target this unique profile.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-04-01.

NM23-H2, an ERβ Associated Protein, as a Prognostic Marker in Breast Cancer

Purpose: Endocrine therapy is a well established therapy for estrogen receptor (ER) positive breast cancer. Two ER have been identified but currently only ERα is used in clinical practice. The role of ERβ in breast cancer is less well understood. Two human NM23 genes exist, NM23-H1 and NM23-H2. Several studies have shown an inverse relationship between overexpression of NM23-H1 in breast cancer and disease aggressiveness. NM23-H2, a metastasis suppressor protein, was recently identified as ERβ associated protein in vascular wall of atherosclerotic lesions, but the prognostic significance of this protein and its association with ERβ has not being studied in breast carcinoma. The purpose of this study was to investigate whether NM23-H2 is expressed in breast cancer and its potential clinical implications.Material and Methods: A cohort of 427 patients with diagnosis of primary invasive breast carcinoma between the period of 1994 to 1997 was used for this study. They all were patients diagnosed and treated at the Leeds Teaching Hospitals, UK. Immunohistochemistry was used primarily to identify the expression of NM23-H2 in this study. Regulation of NM23-H2 in vitro in MCF-7 cells was assessed by Western blotting. p&lt;0.05 was considered statistically significant.Results: Patients ages were 27-92 years (median = 58 years, IQ range 47-69 years) with median follow up of 110 months. Tumour size varied from 1 and 130 mm (median=22.7mm, IQ range 14-26mm). Seventy eight percent were invasive ductal carcinoma NST and 11.5% were invasive lobular; 3.9% were special type (tubular, mucinous); and 6.6% were mixed type. Twenty-three percent of the tumours were grade 1, 43.3% were grade 2 and 33.7% were grade 3. Axillary metastases were present in 51% of the cases. NM23-H2 expression was variable between tumours and demonstrated only in the cytoplasm of breast carcinomas. The percentage of staining ranged from 0% to 100% (median 80%).NM23-H2 was strongly correlated with ERβ1 and ERα (p &lt;0.001; correlation coefficient 0.252 and 0.176 respectively). No correlation was found between NM23-H2 with age, size, grade or lymph node status. NM23-H2 when expressed at levels higher than 30% was associated with improved overall survival (p= 0.030). In a multivariate Cox hazard analysis, NM23-H2 overexpression was a significant predictor of better survival independent of tumor grade, lymph node status, size or ERα. MCF-7 cells treated with 17β-estradiol (E2) expressed higher levels of NM23-H2(17.5kDa) compared with serum treated cells.Conclusion: This is the first time to our knowledge that the expression of NM23- H2 in breast cancer and its association with ERβ has been investigated. Our data provide evidence that immunohistochemical overexpression of NM23 H2 is associated with ERβ and ERα in breast cancer and with improved survival. NM23-H2 might be a good prognostic marker in breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4148.

Methylation Status of Promoters 0K, 0N and a Newly Identified Promoter Regulate ERβ1 Expression in Breast Cancer

Gene expression is regulated at multiple levels, including transcriptional silencing by methylation. ERβ1 is downregulated in breast cancer compared to normal breast and mechanisms surrounding this are unclear. Two novel ERβ mRNA isoforms with distinct 5'-UTRs have been identified, ERβ-0K-1 and ERβ-0N-1. The aim of study was to examine whether methylation at these promoter regions plus a novel promoter identified by our group were involved in ERβ1 regulation (figure 1).Bisulfite modification and direct sequencing analysis were performed for promoters 0K, 0N, and a novel mini CpG island upstream of ERβ exon1 in two ERβ1- and one ERβ1+ breast cancer cell lines. Distinct methylation patterns were observed. Promoter 0N was completely methylated in BT20, partially methylated in MDAMB453 and unmethylated in T47D, while the mini CpG island was methylated in all 3 cell lines. In contrast, promoter 0K was unmethylated. Furthermore, a negative correlation between ERβ1 mRNA expression and the methylation status of promoter 0N was observed in breast cells. To further investigate whether methylation of the ERβ1 promoter was responsible for the loss of ERβ1 expression, BT20 and MDAMB453 cells were treated with either 5-aza-dC, TSA or both, concentrations of which had been previously optimised for each cell line. In BT20 cells which had complete methylation of 0N, both agents were required for induction of ERβ1 and ERβ-0N-1 but not ERβ-0K-1 expression, both of which are part of the 5'UTR region. However in MDAMB453 treatment with 5-aza-dC was sufficient to induce ERβ1 and ERβ-0N-1 expression with no additional re-expression seen with TSA and no effects on ERβ-0K-1. This suggests that promoter 0N is responsible for driving the transcription of ERβ1. On going work is confirming these observations in clinical samples. Our results suggest that promoter 0N plays an important role in regulation of ERβ1 mRNA expression in breast cancer. Our results add to growing literatures which demonstrate ERβ1 is regulated at multiple levels in breast cancer and that DNA methylation is an important mechanism for silencing ERβ1 gene expression.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1148.

miR-92 Is a Novel Regulator of ERβ1 Expression in Breast Cancer

Down-regulation of ERβ1 expression is thought to contribute to carcinogenesis in the breast and consequently is seen in many breast cancers. The molecular mechanisms responsible for the down-regulation of ERβ1 remain unclear. microRNAs are a novel family of regulators of gene expression that have been shown to act on the expression of many critical cancer genes but their relationship with ERβ1 has not so far been demonstrated. The aims of this study were to establish whether miR-92 regulates ERβ1 expression, and whether this regulation plays a role in defining ERβ1 expression levels in breast cancers.Using a bioinformatics approach we initially identified potential binding sites for miR-92 within the 3' untranslated regions of ERβ transcripts using RNAhybrid software (http://bibiserv.techfak.uni-bielefeld.de/rnahybrid/). Two conserved target-sites for miR-92 were identified within the ERβ1 3'-UTR sequence contained within Genebank. We confirmed the expression of these UTRs in MCF7 cells. Next, we performed 3' RACE reactions to determine the 3'-UTR sequence of ERβ1 in MCF7 cellsWe used qPCR analyses of expression in paired normal breast and breast tumour samples (n=6) to examine the relative expression of miR-92 and ERβ1. Upregulation of miR-92 expression was observed in breast tumours compared with normal breast. An inverse relationship with ERβ1 expression was observed in these samples. In a separate cohort of breast tumours (n=36), a significant negative correlation between ERβ1 mRNA and miR-92 was observed (Spearman's correlation coefficient, r = -0.5, p=0.001). Elevated ratios of ERβ1 mRNA /miR92 were also observed in ERβ1 positive compared to ERβ1 negative cells lines.Inhibition of miR-92 in MCF-7 cells increased ERβ1 expression in a dose–dependent manner at RNA levels. Enhanced GFP reporter constructs containing miR-92 binding sites from the 3'-UTR of ERβ1 were used to determine whether miR-92 downregulates ERβ1 via the direct targeting of this 3'-UTR. Inhibition of miR-92 increased the translational efficiency (protein produced per unit of mRNA) of the GFP reporter, confirming that the miR-92 binding sites are a critical regulatory region. Finally, we showed that miR-92 expression was upregulated by 17β-estradiol and downregulated by tamoxifen in MCF7 cells (ERα+ ERβ+) but not in ERβ negative cells (BT20 and MDAMB453), suggesting ERs can mediate miR-92 regulation. Our results demonstrate that ERβ1 expression in breast cancer is regulated by miRNA-92.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4139.

Comparative Biomarker Analysis in 523 Matched Male and Female Breast Cancers

Incidence rates of male breast cancer (MBC) are rising. MBC etiology is poorly understood with most of our current knowledge regarding its biology, natural history and treatment extrapolated from our knowledge of female breast cancer (FBC). Retrospective studies on MBC have suffered from small numbers of cases available from any one centre thus a significant problem in studying this disease is accruing sufficiently large numbers to allow comparative analysis of possible prognostic markers. Using a co-ordinated multi-centre approach, the aim of this study was to conduct the first large scale study to address the relevance of the expression of recognised biomarkers in FBC in the same disease in males. Five hundred and twenty three cases were obtained retrospectively and assimilated into TMAs, including 260 MBCs and 263 cases of stage-matched FBCs. MBC comprised 21 grade 1, 121 grade 2, 68 grade 3, 50 unknown, mean age 67 (range 39-90) with 167 ductal, 4 lobular, 10 papillary, 10, mucinous, 4 DCIS, 1 mixed and 64 unknown. FBC comprised 29 grade 1, 140 grade 2, 94 grade, mean age 58 (range 27-92) with 220 ductal, 23 lobular, 14 mixed and 6 unknown. Four µm TMA sections were analysed using the following biomarkers: hormone receptors (ERα, ERβ1, ERβ2, ERβ5, total PR, PRA, PRB, AR), apoptosis markers (p53, bcl2), basal (CK5/6, CK14) and luminal epithelial markers (CK18, CK19), E-cadherin and HER2. Biomarkers were scored according to published criteria; for ERβ isoforms both nuclear and cytoplasmic immunoreactivity was determined Statistical analysis was conducted using SPSS. Luminal A (ERα+, and/or PR+, HER2-) was seen in 93% of MBC vs. 84% of FBC, Luminal B (ERα+, and/or PR+, HER2+) or HER2 subgroup (ERα-, PR-, HER2+) was not seen in MBC but found in 6% and 2% of FBC, respectively. Basal-like tumours (ERα-, PR-, HER2-, CK5/6+) were infrequent (MBC 2%, FBC 1%) and in MBC these tumours also expressed ERβ isoforms. No differences were observed in grade, stage or LN status between genders. Univariate analysis showed ERα, ERβ1, ERβ5, PRA, AR, p53 were significantly associated with FBC while cytoplasmic ERβ2, bcl2 and e-cadherin were associated with MBC (all P&lt;0.001). Although membranous HER2 was not seen in MBC, many cases displayed nuclear staining. Biomarker profile with respect to clinical outcome is on-going. This work has shown the luminal A phenotype is common in MBC and that gender-specific biomarkers are expressed. As MBC is becoming more common, this information may be useful in identifying biomarkers which might affect outcome.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2109.

Phosphorylation of Estrogen Receptor β at Serine 105 in Primary Breast Cancer

Background: Estrogen receptor (ER) α predicts response to hormonal therapy in breast carcinoma. The role of ERβ is less well understood. ER activities can be modulated by post-translational modifications including phosphorylation and phosphorylated ERα has been correlated with patient outcome. We investigated whether ERβ phosphorylated at Serine 105 (P-S105-ERβ) is expressed in breast carcinoma and assessed its potential clinical implications.Material and Methods: Tissue microarrays comprising 427 breast tumours (23% grade 1, 43% grade 2, 34% grade 3) with median follow up 118 months and 106 endocrine resistant breast tumours (15% grade 1, 41% grade 2, 44% grade 3) with median follow up 71 months were used in this study. Expression of P-S105-ERβ was studied by immunohistochemistry and analysed against clinical data. Regulation of P-S105-ERβ in vitro was assessed by immunofluorescence and Western blotting.Results: Expression of P-S105-ERβ was mainly nuclear and could be abolished by phosphatase pre-incubation, indicating specificity. In the first cohort Allred scoring ranged from 0 to 8 (median 6). Nuclear speckling was observed in 45% of cases. P-S105-ERβ correlated with ERβ1 (Allred score ≥ 3) and was associated with better overall survival (OS) and disease free survival (DFS) (p=0.028 and p=0.027, respectively). In a multivariate Cox hazard analysis, P-S105-ERβ overexpression was a significant predictor of better survival independent of tumor grade, lymph node status, size or ERα. In the endocrine resistant cohort Allred scoring ranged from 0 to 8 (median of 4) and the overexpression of P-S105-ERβ was also associated with improved OS and DFS (p=0.044 and p=0.033, respectively). Nuclear speckling was present in only 11% of cases. The difference in expression of P-S105-ERβ and association with survival outcome between the two cohorts was statistically significant. P-S105-ERβ was expressed in MCF-7 cells and in response to 17β-estradiol (E2); levels were raised within 30 min, and sustained for 24 hours. ERβ1 expression was unaffected by this treatment. Nuclear speckling was also observed and was markedly increased at 24 hours following E2 but not Tamoxifen.Conclusion: This is the first time to our knowledge that the expression of P-S105-ERβ in breast carcinoma has been investigated. Its presence in breast carcinoma and association with improved survival suggest P-S105-ERβ might be a useful additional prognostic marker in breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4141.