High Estrogen Receptor Research Articles

Adjunctive Statistical Standardization of Adjuvant Estrogen Receptor and Progesterone Receptor in Canadian Cancer Trials Group MA.27 Postmenopausal Breast Cancer Trial of Exemestane Versus Anastrozole.

ASCO/College of American Pathologists guidelines recommend reporting estrogen receptor (ER) and progesterone receptor (PgR) as positive with (1%-100%) staining. Statistically standardized quantitated positivity could indicate differential associations of positivity with breast cancer outcomes. MA.27 (ClinicalTrials.gov identifier: NCT00066573) was a phase III adjuvant trial of exemestane versus anastrozole in postmenopausal women with early-stage breast cancer. Immunochemistry ER and PgR HSCORE and % positivity (%+) were centrally assessed by machine image quantitation and statistically standardized to mean 0 and standard deviation (SD) 1 after Box-Cox variance stabilization transformations of square for ER; for PgR, (1) natural logarithm (0.1 added to 0 HSCOREs and 0%+) and (2) square root. Our primary end point was MA.27 distant disease-free survival (DDFS) at a median 4.1-year follow-up, and secondary end point was event-free survival (EFS). Univariate survival with cut points at SDs about a mean of 0 (≤-1; (-1, 0]; (0, 1]; >1) was described with Kaplan-Meier plots and examined with Wilcoxon (Peto-Prentice) test statistic. Adjusted Cox multivariable regressions had two-sided Wald tests and nominal significance P < .05. Of 7,576 women accrued, 3,048 women's tumors had machine-quantitated image analysis results: 2,900 (95%) for ER, 2,726 (89%) for PgR, and 2,582 (85% of 3,048) with both ER and PgR. Higher statistically standardized ER and PgR HSCORE and %+ were associated with better univariate DDFS and EFS (P < .001). In multivariable assessments, ER HSCORE and %+ were not significantly associated (P = .52-.88) with DDFS in models with PgR, whereas higher PgR HSCORE and %+ were significantly associated with better DDFS (P = .001) in models with ER. Adjunctive statistical standardization differentiated quantitated levels of ER and PgR. Patients with higher ER- and PgR-standardized units had superior DDFS compared with those with HSCOREs and %+ ≤-1.

Therapeutic response and outcomes with uncommon breast cancer subtypes in the I-SPY trial 2010-2022.

1 Background: Uncommon histologies are over-represented among high-risk breast cancer (BC) and denote an area with limited trial data and of significant unmet medical need. To better understand trial outcomes in this group and identify signals of tumor responsiveness, we report pathologic complete response (pCR) and early event-free survival (EFS) by disease subtype in the I-SPY2 trial. Additionally, the I-SPY2 trial currently utilizes a combination of tumor molecular signature and receptor status to determine response predictive subtype (RPS) first developed from 987 I-SPY2 patients [Wolf et al, Cancer Cell 2022]. We report disease response rates for those who received what is now known to be optimal RPS guided therapy. Methods: The I-SPY2 platform trial tests novel agents given neo-adjuvantly with a chemotherapy backbone in high-risk BC (HER2 positive, triple negative and high molecular risk estrogen receptor positive BC). Histologic images of research biopsies, local biopsy and surgical pathology reports were reviewed centrally by I-SPY pathologists. Receptor subtype distribution and pCR rates were summarized; and EFS was estimated using the Kaplan Meier method. Association between pCR and EFS was evaluated using the Cox proportional hazard model with significance assessed by the log rank test. Results: 144/2118 (7%) of I-SPY2 participants were identified with metaplastic (60), lobular (55), mucinous (9), micropapillary (8), neuroendocrine (4) and other (8) BCS. Tumor receptor status, pCR rate and EFS by tumor type are shown in the Table. For the full cohort, pCR was associated with better EFS (hazard ratio (95% CI): 0.12 (0.02 - 0.88), p = 0.01). Within metaplastic (metapBC) 11/32 (34%) and 5/28 (18%) patients had a pCR with or without checkpoint blockade, respectively. By RPS group, 9 of 18 (50%) (13 metapBC, 3 other, 2 lobular) in the HER2-Immune+ group who received RPS optimized therapy had a pCR. In this group 6/13 (46%) with metapBC had a pCR. In the HER2+ driven RPS groups, pCR rate in the HER+HER2orBasal was 88% (7/8) and 0% (0/3) in the HER2+Luminal. Conclusions: High pCR rates observed in metapBC and other among subsets of often difficult to treat BC subtypes support novel approaches and provide a roadmap for future study of uncommon BCs. Outcomes were improved when therapy matched RPS vulnerabilities. Participants presenting with uncommon BC subtypes will be prospectively identified in the I-SPY2.2 trial to further develop effective approaches for this group. Clinical trial information: NCT01042379 .[Table: see text]

Intragastric exposure of rats to silver nanoparticles modulates the redox balance and expression of steroid receptors in testes

Nanosilver (AgNPs) is popular nanomaterials used in food industry that makes gastrointestinal tract an essential route of its uptake. The aim of the presented study was to assess the effects of intragastric exposure to AgNPs on redox balance and steroid receptors in the testes of adult Fisher 344 rats. The animals were exposed to 20 nm AgNPs (30 mg/kg bw/day, by gavage) for 7 and 28 days compared to saline (control groups). It was demonstrated that 7-day AgNPs administration resulted in increased level of total antioxidant status (TAS), glutathione reductase (GR) activity, lower superoxide dismutase activity (SOD), decreased glutathione (GSH) level and GSH/GSSG ratio, as well as higher estrogen receptor (ESR2) and aromatase (Aro) protein expression in Leydig cells compared to the 28-day AgNPs esposure. The longer-time effects of AgNPs exposition were associated with increased lipid hydroperoxidation (LOOHs) and decreased SOD activity and androgen receptor protein level. In conclusion, the present study demonstrated the adverse gastrointestinally-mediated AgNPs effects in male gonads. In particular, the short-term AgNPs exposure impaired antioxidant defence with concurrent effects on the stimulation of estrogen signaling, while the sub-chronic AgNPs exposition revealed the increased testicle oxidative stress that attenuated androgens signaling.

Is there a correlation between estrogen receptor expression level and early breast cancer survival? A retrospective study.

e12574 Background: The optimal cut-off of estrogen receptor (ER) positivity is still debatable; however, adjuvant hormonal therapy is usually given if ER expression is ≥ 1%. The present study aims to assess the clinicopathological features and survival outcomes of patients with low compared to high ER expression levels. Methods: In this retrospective, we checked non-metastatic hormonal receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer patients who presented to three hospitals in Egypt and Saudi Arabia between 2016 and 2019. Different clinicopathological factors and data on relapse were checked in patients’ medical records. These data were compared in patients with ER-Low (1–10%) vs. ER-High (&gt;10%) expression levels. Results: We included 419 patients who met the eligibility criteria for the study. Only 3.3% of patients had ER-Low. Compared to the ER-high group, the ER-low expression group was more likely to have grade 3 tumours (64.3% vs. 21.0%, p = &lt;0.0001) and PR-negative tumors (64.3% vs. 16.3%, p = &lt;0.0001). Furthermore, younger age (≤ 50 years) was more frequent in the ER-Low group compared to ER-High patients (71.4% vs. 42.5%, respectively, p = 0.032). Likewise, ER-high patients were more likely to have high ER-staining intensity (74.1% vs. 0.0%, p&lt;0.0001). Disease-free survival (DFS) was numerically improved in patients with ER-high, but without statistical significance. After adjustment of different clinicopathological prognostic factors, the DFS benefit in the ER-high group was more definite (hazard ratio (HR) = 3.59, 95%, confidence interval (CI) = 1.11–11.55, and p value = 0.032). Conclusions: A lower estrogen receptor expression level (varying from 1 to 10%) in hormone-positive early breast cancer patients is an uncommon pattern associated with more aggressive disease features at diagnosis. This group of patients had a lower DFS than those with a higher degree of estrogen receptor expression, although there was no statistically significant difference in OS.

Therapeutic response and outcomes with less common breast cancer subtypes in the I-SPY trial 2011-2022.

582 Background: Uncommon histologies are over-represented among high-risk breast cancer (BC) and denote an area with limited trial data and of significant unmet medical need. To better understand trial outcomes in this group and identify signals of tumor responsiveness, we report pathologic complete response (pCR) and early event-free survival (EFS) by disease subtype in the I-SPY2 trial. Additionally, the I-SPY2 trial currently utilizes a combination of tumor molecular signature and receptor status to determine response predictive subtype (RPS) first developed from 987 I-SPY2 patients (1). We report disease response rates for those who received what is now known to be optimal RPS guided therapy. Methods: The I-SPY2 platform trial tests novel agents given neo-adjuvantly with a chemotherapy backbone in high-risk BC (HER2 positive, triple negative and high molecular risk estrogen receptor positive BC). Histologic images of research biopsies, local biopsy and surgical pathology reports were reviewed centrally by I-SPY pathologists. Receptor subtype distribution and pCR rates were summarized. EFS was estimated using the Kaplan Meier method. Association between pCR and EFS was evaluated using the Cox proportional hazard model with significance assessed by the log rank test. Results: 144/2118 (7%) of I-SPY2 participants were identified with metaplastic (60), lobular (55), mucinous (9), micropapillary (8), neuroendocrine (4) and other (8) BCs. Tumor receptor status, pCR rate and EFS by tumor type are shown in the Table. For the full cohort, pCR was associated with better EFS (hazard ratio (95% CI): 0.12 (0.02 - 0.88), p = 0.01). Within metaplastic (metapBC) 11/32 (34%) and 5/28 (18%) patients had a pCR with or without checkpoint blockade, respectively. By RPS group, 9 of 18 (50%) (13 metapBC, 3 other, 2 lobular) in the HER2-Immune+ group who received RPS optimized therapy had a pCR. In this group 6/13 (46%) with metapBC had a pCR. In the HER2+ driven RPS groups, pCR rate in the HER+HER2orBasal was 88% (7/8) and 0% (0/3) in the HER2+Luminal. Conclusions: High pCR rates observed in metapBC and other among subsets of often difficult to treat BC subtypes support novel approaches and provide a roadmap for future study of uncommon BCs. Outcomes were improved when therapy matched RPS vulnerabilities. Participants presenting with uncommon BC subtypes will be prospectively identified in the I-SPY2.2 trial to further develop effective approaches for this group. 1. Wolf et al, Cancer Cell 2022. Clinical trial information: NCT01042379 . [Table: see text]

Abstract PO5-03-03: Nomogram for predicting brain metastasis in early-stage breast cancer patients

Abstract Nomogram for predicting brain metastasis in early-stage breast cancer patients Background: Brain metastasis is a significant concern for patients with early-stage breast cancer, as it can have a detrimental impact on survival and quality of life. Clinical and pathological characteristics of the primary tumor may be modeled into a nomogram that can predict the risk of brain metastasis. The goal is to create a nomogram and clinical calculator to assist in selection of patients with high risk of brain metastasis to enrich patient population for accrual on clinical trials for the purpose of preventing or delaying emergence of brain metastasis, at an early stage of their disease. Methods: We reviewed all early-stage breast cancer patients (stages I to III) N=40290 from the University of Texas MD Anderson Cancer Center, Houston, TX, from 1/1/1997 to 5/8/2020. We utilized multiple predictive statistical models to identify the most relevant variables and optimal predictive criteria. Variables for the model included patient age, tumor characteristics (such as grade,hormone receptor and HER2 status) and medical treatment (such as chemotherapy and endocrine therapy). The Receiver Operating Characteristic (ROC), and its AUC (area under the curve) was used to demonstrate the performance of the multivariate model to predict the occurrence of brain metastasis at different time points (1 year, 2 years, and 5 years), distinguishing between patients who develop brain metastasis in a time-dependent manner and those who do not. Results: The results showed the following clinical variables to be statistically significant in predicting brain metastasis: younger age, high estrogen and progesterone receptor percentage, higher tumor size; use of aromatase inhibitor therapy, and use of selective estrogen receptor modulator therapy were associated with a decreased risk of brain metastasis. Higher grade, Ki-67 levels, HER2-positive status, lymphovascular invasion and the use of chemotherapy was associated with an increased risk. The AUC values for the prediction of brain metastasis at different time points are as follows: 0.85 at 1 year, 0.83 at 2 years, and 0.82 at 5 years. These values indicate that the multivariate model has good discriminative ability, with higher values indicating a better predictive performance. An AUC of 0.85 suggests that the model has a high probability of correctly distinguishing between patients who will develop brain metastasis and those who will not at 1 year. Conclusions: Our predictive tool holds promise in assisting clinicians when making informed, personalized care decisions for patients at risk of developing brain metastasis. The model will be validated using independent patient cohorts from Institut Jules Bordet, Brussel, Belgium, to assess their accuracy and reproducibility. Continued research and validation will further refine these models, increasing their reliability and their clinical/clinical research applicability. Citation Format: Akshara Singareeka Raghavendra, Nuria Kotecki, Kristofer Jennings, Ottavia Amato, Debu Tripathy, Ahmad Awada, Nuhad Ibrahim. Nomogram for predicting brain metastasis in early-stage breast cancer patients [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-03-03.

Abstract PO3-25-06: Expression of CD28, Fas, PD1, and CTLA4 molecules on cellular immune response in the blood peripheral of patients with locally advanced triple-negative breast cancer

Abstract Background: Locally advanced triple-negative breast cancer (TNBC) represents a public health problem in Brazil; its standard treatment consists of neoadjuvant chemotherapy followed by surgical and radiotherapy, with highly variable success rates are depended on access to appropriate cancer treatment, and the type of pathological response. In the last decade, the immune system's role in breast cancer has gained space by demonstrating the favorable impact of lymphocyte tumor infiltrate (TILs) and gene expression of the immune response, especially in tumors with high proliferation rates and negative estrogen receptors. The cellular immune response is regulated by co-stimulatory and co-inhibitory proteins such as CD28, Fas, PD1, and CTLA4 molecules. Methods: This was a longitudinal study with follow-up performed between 2015 and 2017. The study was conducted at the Hospital de Cancer de Pernambuco and Translational Research Laboratory of the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP). Thirty women (18 to 60 years) diagnosed with locally advanced TNBC submitted to neoadjuvant chemotherapy (NAC), and 30 healthy women as a control group were included. The co-stimulatory and co-inhibitory proteins analyses were performed in the peripheral blood of TNBC women before (Pre-NAC) and after NAC (Post-NAC) Results: High levels of CD28+CD3+ T, CD28+CD4+ T, PD1+CD3+ T, and CTLA4+CD3+ T cells in the pathological complete response (pCR) and non-pCR groups compared to the control group (p &amp;lt; 0.05). High levels of Fas+CD4+T cells and PD1+CD8+T cells in the non-pCR compared to the pCR group (p &amp;lt; 0.05). In the paired analysis, significant differences were observed in CD3+T and CD4+T levels with CD28, Fas, and PD1 expression between pre- and post-NAC. Conclusion: Fas+CD4+T and PD1+CD8+T levels in peripheral blood in TNBC are associated with pCR, suggesting potential predictive biomarkers of NAC response. Preliminary results allow us to infer that neoadjuvant chemotherapy modulates the cellular immune response in TNBC women. Citation Format: Marcelo Salgado, Fernando Soares, Denise Viana, Amanda Salgado, Carolina Vasconcelos, Carlos Eduardo Anunciação, Eduardo Salgado, Leuridan Torres. Expression of CD28, Fas, PD1, and CTLA4 molecules on cellular immune response in the blood peripheral of patients with locally advanced triple-negative breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-25-06.

Abstract PO2-13-11: High circulating tumor DNA (ctDNA) concentration was associated with shorter progression free survival in patients with metastatic breast cancer

Abstract Background: Metastatic breast cancer can be classified into different subtypes depending on hormone receptor (HR) and HER2 status. The subtype can change during tumor progression, and repeated biopsy is needed to deliver the most appropriate treatment every time a new lesion is found. It is not always possible to get a new biopsy from metastatic sites, and therefore liquid biopsy using circulating tumor DNA (ctDNA) is suggested as an alternative method to replace conventional biopsy. Methods: We performed a prospective serial collection of 65 ctDNA samples from 17 patients with metastatic breast cancer (mBC) at Seoul National University Hospital from October 2020 to March 2022. We used IMBdx AlphaLiquid®100 method to detect the genetic changes and analyzed the correlation with clinical outcomes. Results: Median age was 45 (range 32 – 62). Fifteen patients (88.2%) were relapsed mBC and most of the patients (14/17: 82.4%) were HR-positive and HER2-negative. Most of the patients had their ctDNA examined at baseline and at the time of maximal response and/or at progression. Fifteen patients (88.2%) received systemic therapy including hormone therapy, anti-HER2 therapy, and cytotoxic chemotherapy. Eight patients (47.1%) were on the first-line treatment for mBC, and 7 patients (41.2%) were on the second or later lines for mBC at the time of baseline sampling. The concentration of ctDNA and the sum of mutated allelic frequency was calculated for each sample. The ctDNA concentration ranged from 0.71 to 1386.00 ng/mL, and the median value was 5.37 ng/mL. We dichotomized these samples into two groups, with ctDNA concentration either higher or lower than the median value. Then we analyzed progression free survival (PFS) of each group. Patients with higher ctDNA concentration showed shorter PFS (7 mo. vs. not reached, p&amp;lt; 0.001). The sum of mutated allelic frequency ranged from 0.00% to 223.46% and the median value was 6.36%. Patients with higher mutated allelic frequency showed shorter PFS (6 mo. vs. 22 mo., p&amp;lt; 0.001). In addition, the PFS was significantly worse in patients who had mutated PIK3CA (5 mo vs. 22 mo, p&amp;lt; 0.001). The patients with mutated TP53 also showed shorter PFS (6 mo vs. 17 mo, p&amp;lt; 0.001) in univariate analysis. High estrogen receptor positivity in immunohistochemistry was correlated with lower mutated allelic frequency in ctDNA (p=0.003) but had no impact on the concentration of ctDNA (p=0.165). The concentration of ctDNA differed by metastatic sites. Patients with metastases to bones (p=0.007), liver (p&amp;lt; 0.001), soft tissue or lymph nodes (p=0.002) were more likely to have higher concentrations of ctDNA, while patients with brain metastases had significantly lower ctDNA concentration (p=0.006). When the sum of mutated allelic frequency of ctDNA and metastatic sites was analyzed, bone (p=0.001), liver (p&amp;lt; 0.001), and soft tissue or lymph node (p&amp;lt; 0.001) metastases had a positive correlation, while brain had negative correlation (p=0.017). Lung or pleural metastases had no significant correlation with ctDNA, neither concentration (p=0.271) nor mutated allelic frequency (p=0.965). Conclusion: Patients with mBC with higher concentrations of ctDNA or higher mutated allelic frequency of ctDNA at baseline showed significantly shorter PFS. PIK3CAmt and TP53mt detected by liquid biopsy could be used as a poor prognostic biomarkers for mBC patients. Citation Format: Hanbaek Yi, Tae-Yong Kim, Myung Geun Song, Hwang-Phill Kim, Tae-You Kim, Jinyong Kim, Dae-Won Lee, Kyung-Hun Lee, Seock-Ah Im. High circulating tumor DNA (ctDNA) concentration was associated with shorter progression free survival in patients with metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-13-11.

Exemestane plus everolimus and palbociclib in metastatic breast cancer: clinical response and genomic/transcriptomic determinants of resistance in a phase I/II trial

The landscape of cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) resistance is still being elucidated and the optimal subsequent therapy to overcome resistance remains uncertain. Here we present the final results of a phase Ib/IIa, open-label trial (NCT02871791) of exemestane plus everolimus and palbociclib for CDK4/6i-resistant metastatic breast cancer. The primary objective of phase Ib was to evaluate safety and tolerability and determine the maximum tolerated dose/recommended phase II dose (100 mg palbociclib, 5 mg everolimus, 25 mg exemestane). The primary objective of phase IIa was to determine the clinical benefit rate (18.8%, n = 6/32), which did not meet the predefined endpoint (65%). Secondary objectives included pharmacokinetic profiling (phase Ib), objective response rate, disease control rate, duration of response, and progression free survival (phase IIa), and correlative multi-omics analysis to investigate biomarkers of resistance to CDK4/6i. All participants were female. Multi-omics data from the phase IIa patients (n = 24 tumor/17 blood biopsy exomes; n = 27 tumor transcriptomes) showed potential mechanisms of resistance (convergent evolution of HER2 activation, BRAFV600E), identified joint genomic/transcriptomic resistance features (ESR1 mutations, high estrogen receptor pathway activity, and a Luminal A/B subtype; ERBB2/BRAF mutations, high RTK/MAPK pathway activity, and a HER2-E subtype), and provided hypothesis-generating results suggesting that mTOR pathway activation correlates with response to the trial’s therapy. Our results illustrate how genome and transcriptome sequencing may help better identify patients likely to respond to CDK4/6i therapies.

A phase II, multicenter, open-label study of abemaciclib and letrozole in patients with estrogen receptor-positive rare ovarian cancer: ALEPRO trial

BackgroundLow-grade serous and endometrioid ovarian cancers and adult-type granulosa cell tumors are rare ovarian malignancies that show high estrogen receptor positivity. Recurrences of these subtypes of ovarian cancer are often...

Abstract B031: High risk no specific molecular profile (HR-NSMP) endometrial cancer can be stratified into three subgroups based on tumor grade and estrogen receptor status with differing clinicopathologic characteristics and outcomes

Abstract Introduction: Recent publications have identified ‘low risk’ (LR-NSMP) and ‘high risk’ no specific molecular profile (HR-NSMP) endometrial cancers (ECs). Although LR-NSMP (low grade (G1/2) estrogen receptor (ER) positive tumors have extremely low rates (&amp;lt;2%) of death from disease and are considered candidates for de-escalation of adjuvant therapy, little is known about the newly defined entity of HR-NSMP (G3 and/or ER-negative), including optimal management, with 27% of HR-NSMP patients dying from their disease We aimed to perform in-depth characterization of a cohort of HR-NSMP ECs to identify additional prognostic or predictive features that may inform management. Methods: Clinicopathologic data collection, immunohistochemistry (IHC), and next generation sequencing was performed on a cohort of 148 HR-NSMP ECs testing for associations with outcomes. Three subgroups of HR-NSMP were assessed: i) low grade without any ER expression (G1/2ER-, n=40), ii) high grade with ER (G3ER+, n=67), and iii) high grade without ER expression (G3ER-, n=41). Results: In a univariate analysis, advanced stage (III/IV), positive lymph node (LN) status, no LN assessment, and PIK3CA mutations were associated with inferior progression-free survival (PFS), disease specific survival (DSS), and overall survival (OS). HR-NSMP patients with positive LNs had a hazard ratio (HR) of death of 7.55 (95% CI: 3.41−16.73) compared to node negative. Additionally, patients with no LN assessment had an increased risk of death with a HR of 2.33 (95% CI: 1.12−4.85) compared to node negative. Within the three HR-NSMP subgroups, the worst OS (HR 7.06, CI 4.12-12.09, p&amp;lt; 0.001), DSS (HR 20.43, CI 10.14-41.19, p&amp;lt; 0.001), and PFS (HR 3.69, CI 1.59-8.63, p&amp;lt;0.001) were observed in patients with both adverse features (G3ER-). PIK3CA mutations were found in 32.7% of all HR-NSMP tumors tested (G1/2ER- 45.5%, G3ER+ 42.3%, G3ER- 6.7%) and associated with inferior OS (HR 4.84, CI 1.21-19.41, p=0.014), DSS (HR 4.84, CI 1.21-19.41, p=0.014), and PFS (HR 3.22, CI=1.08-9.66, p=0.028). There was a trend towards decreased OS and DSS in HR-NSMP patients with overexpression of HER2 IHC. L1CAM IHC overexpression and CTNNB1 mutation status were not associated with outcomes when assessed across all HR-NSMP or within subgroups. Conclusion: Among HR-NSMP ECs, the worst clinical outcomes were observed in patients harboring both high grade and ER negative tumors. In contrast to LR-NSMP ECs where patients who had no lymph node assessment had excellent outcomes mirroring node negative status, HR-NSMP patients who had no nodal assessment had a high rate of recurrence and death from disease suggesting the importance of comprehensive staging in this cohort. PIK3CA appears to be a prognostic stratification feature within HR-NSMP and represents a potential therapeutic pathway. More work is needed to understand the association of HER2 expression and ER status and whether HER2 -targeted therapies represent actionable opportunities for these patients. Citation Format: Andrea Neilson, Amy Jamieson, Derek Chiu, Samuel Leung, Amy Lum, Jennifer Pors, Stefan Kommoss, Aline Talhouk, David G. Huntsman, Naveena Singh, C. Blake Gilks, Jessica N. McAlpine. High risk no specific molecular profile (HR-NSMP) endometrial cancer can be stratified into three subgroups based on tumor grade and estrogen receptor status with differing clinicopathologic characteristics and outcomes [abstract]. In: Proceedings of the AACR Special Conference on Endometrial Cancer: Transforming Care through Science; 2023 Nov 16-18; Boston, Massachusetts. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(5_Suppl):Abstract nr B031.

The use of transcriptomic data in developing biomarkers in breast cancer

AbstractHER2 and hormone receptors are biomarkers for selecting breast cancer therapy and predicting outcomes. In the era of antibody‐drug conjugates (ADC), a relatively low HER2 expression level is adequate for targeting tumor cells. We explored the potential of RNA profiling, determined by next generation sequencing (NGS), to provide more flexible clinical biomarkers as compared with immunohistochemistry (IHC) or fluorescent in situ hybridization (FISH). Data from 57 breast cancers was used to study biomarker levels as detected by routine clinical transcriptomic tests. HER2 (ERBB2), estrogen receptor alpha (ESR1), and androgen receptor (AR) mRNA levels were compared with IHC and FISH results. There was a significant overlap in the levels of ERBB2 mRNA between cases scored by IHC as zero, 1+, and 2+. This variation correlated with progression‐free survival (PFS). Similarly, the ESR1 RNA accurately reflected estrogen receptor (ER) status. Patients with high AR mRNA had better PFS (p = 0.05). Patients expressing high ER and AR levels had better PFS than those expressing low ESR1 and AR (p = 0.03). These findings suggest that RNA analysis can be an alternative to IHC and FISH and provides continuous data that can better determine cut‐off points for predicting response to ADC.

Optimization of small molecule degraders and antagonists for targeting estrogen receptor based on breast cancer: current status and future.

The estrogen receptor (ER) is a classical receptor protein that plays a crucial role in mediating multiple signaling pathways in various target organs. It has been shown that ER-targeting therapies inhibit breast cancer cell proliferation, enhance neuronal protection, and promote osteoclast formation. Several drugs have been designed to specifically target ER in ER-positive (ER+) breast cancer, including selective estrogen receptor modulators (SERM) such as Tamoxifen. However, the emergence of drug resistance in ER+ breast cancer and the potential side effects on the endometrium which has high ER expression has posed significant challenges in clinical practice. Recently, novel ER-targeted drugs, namely, selective estrogen receptor degrader (SERD) and selective estrogen receptor covalent antagonist (SERCA) have shown promise in addressing these concerns. This paper provides a comprehensive review of the structural functions of ER and highlights recent advancements in SERD and SERCA-related small molecule drugs, especially focusing on their structural optimization strategies and future optimization directions. Additionally, the therapeutic potential and challenges of novel SERDs and SERCAs in breast cancer and other ER-related diseases have been discussed.

Prevalence of ESR1 gene mutations in gynecologic malignancies with high-estrogen receptor expression (1283)

Prevalence of ESR1 gene mutations in gynecologic malignancies with high-estrogen receptor expression (1283)

Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

Despite similar infection rates, COVID-19 has resulted in more deaths in men than women. To understand the underlying mechanisms behind this sex-biased difference in disease severity, we infected K18-human angiotensin converting enzyme 2 (ACE2) mice of both sexes with SARS-CoV-2. Our study revealed a unique protein expression profile in the lung microenvironment of female mice. As a result, they were less vulnerable to severe infection, with higher ACE2 expression and a higher estrogen receptor α (ERα)/androgen receptor (AR) ratio that led to increased antiviral factor levels. In male mice, inhaling recombinant ACE2 neutralized the virus and maintained the ERα/AR ratio, thereby protecting the lungs. Our findings suggest that inhaling recombinant ACE2 could serve as a decoy receptor against SARS-CoV-2 and protect male mice by offsetting ERα-associated protective mechanisms. Additionally, our study supports the potential effectiveness of recombinant ACE2 therapy in human lung organoids infected with the Delta variant.

Distinct histopathological features are associated with molecular subtypes and outcome in low grade serous ovarian carcinoma

Low grade serous ovarian carcinoma (LGSOC) demonstrates unique clinical and molecular features compared to other ovarian cancer types. The relationship between common histological features of LGSOC and molecular events, such as hormone receptor expression patterns and MAPK gene mutation status, remains poorly understood. Recent data suggest some of these molecular features may be biomarkers of response to recently introduced biologically-targeted therapies, namely endocrine therapy and MEK inhibitors. We utilize a cohort of 63 pathologically-confirmed LGSOC cases with whole exome sequencing and hormone receptor expression data to investigate these relationships. LGSOC cases demonstrated uniformly high oestrogen receptor (ER) expression, but variable progesterone receptor (PR) expression intensity. 60% and 37% of cases demonstrated micropapillary and macropapillary patterns of stromal invasion, respectively. 63% of cases demonstrated desmoplasia, which was significantly associated with advanced disease stage and visible residual disease after cytoreductive surgery. MAPK-mutant cases (KRAS, BRAF, NRAS) more frequently demonstrated macropapillary stromal invasion, while Chr1p loss was associated with desmoplasia and low PR expression. Presence of micropapillary stromal invasion and low PR expression were associated with significantly poorer survival after accounting for stage and residual disease status. Together, these data identify novel relationships between histopathological features and molecularly-defined subgroups in LGSOC.

Positive surgical margins after breast-conserving surgery for ductal carcinoma in-situ: does histologic grade or estrogen receptor status matter?

DCIS has been shown to have a higher rate of positive margins following breast-conserving surgery (BCS) than invasive breast cancer. We aim to analyze certain factors of DCIS, specifically histologic grade and estrogen receptor (ER) status, in patients with positive surgical margins following BCS to determine if there is an association. A retrospective review of our institutional patient registry was performed to identify women with DCIS and microinvasive DCIS who underwent BCS by a single surgeon from 1999 to 2021. Demographics and clinicopathologic characteristics between patients with and without positive surgical margins were compared using chi-square or Student's t-test. We assessed factors associated with positive margins using univariate and multivariable logistic regression. Of the 615 patients evaluated, there was no significant difference in demographics between the patients with and without positive surgical margins. Increasing tumor size was an independent risk factor for margin positivity (P = < 0.001). On univariate analysis both high histologic grade (P = 0.009) and negative ER status (P = < 0.001) were significantly associated with positive surgical margins. However, when adjusted in multivariable analysis, only negative ER status remained significantly associated with margin positivity (OR = 0.39 [95% CI 0.20-0.77]; P = 0.006). The study confirms increased tumor size as a risk factor for positive surgical margins. We also demonstrated that ER negative DCIS was independently associated with a higher rate of positive margins after BCS. Given this information, we can modify our surgical approach to reduce rate of positive margins in patients with large-sized ER negative DCIS.

Abstract 967: Real-world transcriptomic biomarkers as replacement for immunohistochemistry and FISH studies in breast cancer

Abstract Background: Human epidermal growth factor receptor-2 (HER2) and hormone receptors are typically used as binary biomarkers for selecting breast cancer therapy. There is a need to explore the clinical relevance of these biomarkers as continuous variables. This is particularly relevant for the new class of antibody-drug conjugates (ADC), in which a relatively low HER2 expression level is adequate for targeting tumor cells. We explored the potential of RNA profiling, determined by next generation sequencing (NGS), to provide more flexible clinical biomarkers as compared with immunohistochemistry (IHC) or fluorescent in situ hybridization (FISH). Methods: Clinical and laboratory data from 57 breast cancers collected by the COTA real-world data company were used to study biomarker levels as detected by routine clinical transcriptomic tests. HER2 (ERBB2), estrogen receptor alpha (ESR1), and androgen receptor (AR) mRNA levels were compared with reported HER2 and estrogen receptor (ER) IHC and FISH results. Results: RNA levels accurately reflected and predicted HER2 amplification (see table below). Importantly, RNA data showed significant variation and overlap in the levels of ERBB2 mRNA between cases scored by IHC as zero, 1+, and 2+. This variation correlated with progression-free survival (PFS). Similarly, the ESR1 RNA levels accurately reflected ER status and demonstrated significant variation between positive cases. RNA data also showed significant variations in the AR levels. Patients wssith high AR mRNA levels had significantly better PFS (P=0.05). Patients expressing high ER and AR levels had significantly better PFS than those expressing low ESR1 and AR levels (P=0.03). Conclusions: These findings suggest that RNA analysis using NGS is an alternative to IHC and FISH. RNA provides continuous data that can determine cut-off points predicting response to therapy and should be explored in predicting ADC response. ERBB2 mRNA levels (FPKM) in various HER2 IHC groupss IHC Score Valid N Mean Median Minimum Maximum Quartile Range Std.Dev. Zero 19 231 243 63 537 170 110 Zero vs one 3 151 155 45 253 208 104 Zero to one vs one 18 397 302 172 845 365 222 One Vs two 13 495 423 159 1094 273 284 Two vs three 4 7523 7649 937 13859 7183 5310 Citation Format: Maher Albitar, Andre Goy, Andrew Pecora, Deena Graham, Donna Donna McNamara, Ahmad Ahmad Charifa, Andrew IP, Wanlong Ma, Stanley Waintraub. Real-world transcriptomic biomarkers as replacement for immunohistochemistry and FISH studies in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 967.

Functional estrogen receptor signal transduction pathway activity and antihormonal therapy response in low-grade ovarian carcinoma.

Advanced low-grade ovarian carcinoma (LGOC) is difficult to treat. In several studies, high estrogen receptor (ER) protein expression was observed in patients with LGOC, which suggests that antihormonal therapy (AHT) is a treatment option. However, only a subgroup of patients respond to AHT, and this response cannot be adequately predicted by currently used immunohistochemistry (IHC). A possible explanation is that IHC only takes the ligand, but not the activity, of the whole signal transduction pathway (STP) into account. Therefore, in this study, the authors assessed whether functional STP activity can be an alternative tool to predict response to AHT in LGOC. Tumor tissue samples were obtained from patients with primary or recurrent LGOC who subsequently received AHT. Histoscores of ER and progesterone receptor (PR) were determined. In addition, STP activity of the ER STP and of six other STPs known to play a role in ovarian cancer was assessed and compared with the STP activity of healthy postmenopausal fallopian tube epithelium. Patients who had normal ER STP activity had a progression-free survival (PFS) of 16.1months. This was significantly shorter in patients who had low and very high ER STP activity, with a median PFS of 6.0 and 2.1months, respectively (p<.001). Unlike ER histoscores, PR histoscores were strongly correlated to the ER STP activity and thus to PFS. Aberrant low and very high functional ER STP activity and low PR histoscores in patients with LGOC indicate decreased response to AHT. ER IHC is not representative of functional ER STP activity and is not related to PFS.

Abstract P4-02-14: Gain of HER2 Amplification in Patients with HR+/HER2- and Triple Negative Early Breast Cancer Treated with Neoadjuvant Chemotherapy

Abstract Background: Neoadjuvant chemotherapy (NAC) is standard of care for the majority of patients with clinical stage II-III triple negative breast cancer (TNBC) and is considered in high-risk patients with hormone receptor positive (HR+)/human epidermal growth factor receptor 2 (HER2) negative (-) tumors, with expected pathological complete response (pCR) rates of 40-60% and 10-12%, respectively. In HER2- patients with residual disease (RD) after NAC, there is limited data on rates of gain of HER2 amplification. The biological and clinical significance of this phenomenon is unknown and determining the best adjuvant therapy for these patients remains a challenge. We sought to determine the rate of HER2 gain in a cohort of consecutive patients with HER2- breast cancer (BC) treated with NAC. Methods: From 01/2021 to 12/2021, we identified patients with HER2- breast cancer treated with NAC followed by surgery at our institution. Patients who received neoadjuvant endocrine therapy were excluded. The rates of pCR (ypT0/is ypN0) and HER2 status pre- and post-NAC were assessed. Estrogen receptor (ER), progesterone receptor (PR) and HER2 status on surgery specimens were internally determined for all patients using ASCO/CAP 2020 guidelines. ER-low was defined as ER expression by immunohistochemistry (IHC) 1-10%. Results: We included 256 patients, 130 (51%) HR+/HER2- [13/130(10%) ER-low] and 126 (49%) TNBC. Median age was 48 years (range 25-82) and the majority presented with clinical T2 (57%) and N1 (59%). Of 130 patients with HR+/HER2-tumors, 120 (92%) received dose-dense (dd) doxorubicin/cyclophosphamide-paclitaxel (AC-T). Of 126 TNBC patients, 46 (37%) received ddAC followed by carboplatin in combination with paclitaxel +/- pembrolizumab. Centralized HER2 status assessment on the core biopsy was performed in 22% of samples. Overall, pCR was achieved in 40% of TNBC and 11% of HR+/HER2-. Among the 192 patients with RD, the rate of HER2 gain was 8/192 (4%), including 3% (2/76) of TNBC and 5% (6/116) of HR+/HER2- patients. 7 of the 8 patients (88%) converted from IHC 1+ or 2+ fluorescence in situ hybridization (FISH) not amplified on core biopsy to IHC 2+ FISH amplified on the surgical specimen. In only 1 case, the HER2 status converted from IHC2+ FISH not amplified to IHC3+. 3/8 patients had multifocal disease. All 6 patients with HR+/HER2- BC and HER2 gain had high (&amp;gt;90%) ER expression (Table 1). All but one patient with HER2 gain received adjuvant anti-HER2 therapy. After a median follow-up of 10 months, no recurrence events occurred in this group.12 of the remaining 184 patients experienced a recurrence [11 distant recurrences (8 and 3, in the TNBC and HR+/HER2- groups, respectively), and there was 1 local event (localized chest wall recurrence) in the HR+/HER2- group]. Conclusions: At a single center, we found that in patients with HER2- BC treated with NAC, HER2 gain in patients with RD was uncommon and occurred more frequently in those with HR+ tumors. Analysis of a larger cohort is ongoing to corroborate these results. It is remains to be determined if this phenomenon represents a true HER2 status conversion or tumor heterogeneity. Table 1: Clinico-pathological characteristics of patients with HER2 gain on residual disease Citation Format: Emanuela Ferraro, Sonya Chew Minmin, Anton Safonov, Andrea V. Barrio, Shanu Modi, Andrew D Seidman, Hanna Y Wen, Edi Brogi, Mark E. Robson, Chau T Dang. Gain of HER2 Amplification in Patients with HR+/HER2- and Triple Negative Early Breast Cancer Treated with Neoadjuvant Chemotherapy [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-02-14.