Estrogen Receptor Research Articles

New insights into the role of the CHI3L2 protein in invasive ductal breast carcinoma

AbstractChitinase-like proteins have multiple biological functions that promote tumor growth, angiogenesis and metastasis. Expression of CHI3L2, which is similar in structure to CHI3L1, is detected in glioma cells and tumor-associated macrophages (TAMs) in glioma and breast cancer. However, its exact role remains unclear. We analyzed the expression of CHI3L2 in 74 invasive ductal breast carcinoma (IDC) tumors, breast cancer and macrophages cell cultures using immunohistochemistry, immunofluorescence, Western blot and PCR methods. Clinicopathologic data were included in the analysis. The results obtained show that CHI3L2 expression decreases with increasing degree of tumor grade and negative status of estrogen (ER) and progesterone receptors (PR). Furthermore, CHI3L2 is significantly and positively correlated with phosphorylation of STAT-3 and ERK1/2 signaling pathways, but negatively correlated with macrophage infiltration. CHI3L2 is expressed both in the cytoplasm of cancer cells and in macrophages and may regulate STAT-3 and ERK1/2 phosphorylation in breast cancer cell lines. Analysis of the clinicopathologic data revealed that CHI3L2 levels had no effect on patient survival. CHI3L2 expression may be specific for cancer cells in IDC and involved in cross-talk with the tumor microenvironment. Our study has shown that IDC cancer cells express the CHI3L2 protein, possibly indicating a novel function of this protein.

Pre-diagnosis blood DNA methylation profiling of twin pairs discordant for breast cancer points to the importance of environmental risk factors

Abstract Background Assessment of breast cancer (BC) risk generally relies on mammography, family history, reproductive history, and genotyping of major mutations. However, assessing the impact of environmental factors, such as lifestyle, health-related behavior, or external exposures, is still challenging. DNA methylation (DNAm), capturing both genetic and environmental effects, presents a promising opportunity. Previous studies have identified associations and predicted the risk of BC using DNAm in blood; however, these studies did not distinguish between genetic and environmental contributions to these DNAm sites. In this study, associations between DNAm and BC are assessed using paired twin models, which control for shared genetic and environmental effects, allowing testing for associations between DNAm and non-shared environmental exposures and behavior. Results Pre-diagnosis blood samples of 32 monozygotic (MZ) and 76 dizygotic (DZ) female twin pairs discordant for BC were collected at the mean age of 56.0 years, with the mean age at diagnosis 66.8 years and censoring 75.2 years. We identified 212 CpGs (p < 6.4*10–8) and 15 DMRs associated with BC risk across all pairs using paired Cox proportional hazard models. All but one of the BC risks associated with CpGs were hypomethylated, and 198/212 CpGs had their DNAm associated with BC risk independent of genetic effects. According to previous literature, at least five of the top CpGs were related to estrogen signaling. Following a comprehensive two-sample Mendelian randomization analysis, we found evidence supporting a dual causal impact of DNAm at cg20145695 (gene body of NXN, rs480351) with increased risk for estrogen receptor positive BC and decreased risk for estrogen receptor negative BC. Conclusion While causal effects of DNAm on BC risk are rare, most of the identified CpGs associated with the risk of BC appear to be independent of genetic effects. This suggests that DNAm could serve as a valuable biomarker for environmental risk factors for BC, and may offer potential benefits as a complementary tool to current risk assessment procedures.

Abstract A010: Development and characterization of novel models of lobular breast cancer metastases

Abstract Invasive lobular carcinoma (ILC) is the most common special histological subtype of breast cancer, after No Special Type (NST, ductal carcinoma/IDC), and affects 10-15% of all breast cancer patients. ILC is characterized by E-cadherin loss, Estrogen Receptor (ER) positivity, and a distinct single file invasive growth pattern associated with a unique pattern of metastasis. ILC metastasizes to common breast cancer sites like bone and lung, but ILC also spreads to gynecologic tissues, the peritoneum, gastrointestinal tract and central nervous system - with enrichment for orbital and leptomeningeal metastases. In vitro and in vivo models of ILC metastasis have not been extensively developed. Models of spontaneous metastasis from ER+ breast cancer overall are critically limited; ER+ ILC metastases models present only micro-metastatic disease with extremely long latency (>9 months). Together these issues limit research on the unique nature of metastatic ILC. We leveraged mammary intraductal (MIND) xenografting with two ER+ ILC cell lines (MM134 and 44PE) and confirmed prior reports that these lines spontaneously metastasize to bone, brain, ovary, uterus, lung, and adrenal glands with up to 100% incidence. Importantly, we find that supplementation with low dose estradiol (E2) in drinking water rapidly advances metastatic progression, but not primary tumor growth. Using ex vivo bioluminescence imaging (BLI), we find BLI+ lesions are detectable as early as 90 days. At 150 days post-challenge, 100% of mice have BLI+ metastases at multiple sites. Beyond 22 weeks, 100% of mice present with symptomatic and ultimately lethal CNS metastases. BLI+ macro-metastatic lesions were isolated and expanded ex vivo as organotrophic cell line variants. Analysis of RNA-seq data is ongoing to evaluate 1) common factors enriched in metastatic ILC, and 2) organotrophic factors and pathways enriched in specific metastatic sites. In patients with ILC, bone metastases are typically the first site of metastatic development, occur at a higher incidence versus NST, and are associated with increased morbidity. Bone metastases from ILC patients are more osteogenic compared to the characteristically osteolytic lesions of NST. To examine how ILC cells may promote osteoblastic responses, we prepared ILC and NST conditioned media (CM) and applied it to differentiating osteoblasts (OB). We observed increased OB differentiation and increased mineral deposition with ILC CM compared to NST CM, supporting that ILC cell lines have a distinct impact on the bone microenvironment which may manifest in vivo yet be defined in vitro. Collectively, our observations support that ER+ ILC cell lines can recapitulate key features of clinical disease progression, including spontaneous metastasis mimicking clinical phenotypes. We are leveraging these models to better understand the ILC metastatic cascade and adaptation to unique metastatic niches, and to identify shared and unique attributes of ILC metastases that can be exploited for advancing therapeutics. Citation Format: Joseph L. Sottnik, Matthew J. Sikora. Development and characterization of novel models of lobular breast cancer metastases [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr A010.

Abstract C032: The impact of neoadjuvant endocrine therapy (NET) in ER+ breast cancer tumor microenvironment and metastasis

Abstract Breast cancer is the most common cancer in women worldwide and the second leading cause of death. The Estrogen Receptor positive (ER+) subtype constitutes approximately 80% of the yearly 250,000 breast cancer diagnoses in the US. Anti-estrogen endocrine therapy, administered either pre- or post-operatively, is the cornerstone treatment for all stages of breast cancer. Pre- operative or neoadjuvant endocrine therapy (NET) reduces pre-surgical tumor burden, improves surgical outcome, and provides prognostic information. Although the treatment often has a favorable initial response, about 20% of patients eventually develop resistance and recurrent disease, even decades after the primary diagnosis.We hypothesized that resistance in NET is mediated through pro-metastatic changes in the tumor microenvironment affecting either (i) dissemination machinery or (ii) cancer cell phenotype.The main mode of breast cancer hematogenous dissemination to distant sites is through intravasation portals called Tumor Microenvironment of Metastasis (TMEM) doorways. Each TMEM doorway consists of a tumor cell overexpressing the actin-regulatory protein MENA, a Tie2high/ VEGFAhigh macrophage and an endothelial cell, all in direct contact. TMEM doorway activity leads to vascular opening events, during which tumor cells located in areas around TMEM doorways intravasate and disseminate to secondary sites. Therefore, to investigate the impact of NET on cancer cell dissemination, we evaluated its effect on (i) TMEM doorway score (the number of TMEM doorways per tissue area), (ii) TMEM doorway opening, (iii) the number of circulating tumor cells and (iv) the number of disseminated tumor cells. We used the orthotopic MCF7 breast cancer xenograft model grown in NOD/SCID mice and tested two drugs widely used in NET, Fulvestrant (a Selective Estrogen Receptor Degrader) and Tamoxifen (a Selective Estrogen Receptor Modulator). NET did not affect the TMEM doorway score, TMEM doorway activity, the number of CTCs or the number of DTCs. We are now focused on evaluating the effect of NET on the density of cancer cells which are upregulated in programs of invasion, stemness, and dormancy. This “Triple Threat Phenotype (TTP)” gives tumor cells an enhanced ability to disseminate to and colonize distant organs. To this effect we will stain primary MCF7 tumors from NET and vehicle-treated mice for markers of invasiveness (MENA), stemness (SOX9) and dormancy (NR2F1). Detecting any changes in the phenotype of metastatic tumor cells following NET will help us understand underlying mechanisms of endocrine therapy resistance and may lead to new therapeutic targets and improve patient outcomes. Citation Format: Anastasia Aristoteleia Chondronikola, Dimitra Anastasiadou, Aliona Zintiridou, Camille L. Duran, Nicole Barth, Burcu Karadal-Ferrena, Erika Pereira-Zambalde, Lina Ariyan, Suryansh Shukla, George S. Karagiannis, David Entenberg, John S. Condeelis, Maja H. Oktay. The impact of neoadjuvant endocrine therapy (NET) in ER+ breast cancer tumor microenvironment and metastasis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C032.

Abstract C011: The impact of reproductive factors on breast tumor and normal-adjacent tissue immune profile from menarche to menopause

Abstract Background: Reproductive factors and sex hormones are tightly linked to systemic immunity. However, no studies have examined whether reproductive factors and exogenous hormone use modulate the immune microenvironment of breast tissue. Methods: We prospectively evaluated the associations of reproductive factors (age at menarche, parity, age at first birth, age at menopause, and menopausal status) and exogenous hormone use (oral contraceptives, and menopausal hormone therapy (MHT)) with breast tumor and normal-adjacent tissue immune cell markers among 935 breast cancer cases in the Nurses’ Health Studies. We deconvoluted immune cell abundance using CIBERSORTx and derived gene expression signatures of markers for immune checkpoint (PD1, PDL1, and CTLA4), co-regulatory signal and antigen presentation (MHC class I/ II and T cell receptor) and mammary cytokine signaling (IFN gamma, IL2, IL4, IL12, IL13, TGF beta). Linear regression was used with adjustment for potential confounders. Results: Majority of participants had estrogen receptor (ER)-positive breast cancer (81%) and were post-menopausal at diagnosis (72%). Compared to tumors from pre-menopausal women, tumors from post-menopausal women had higher signature scores for tumor pro-inflammatory cytokine signaling (IFN gamma, IL2, IL4, IL12, IL13, TGF beta) and antigen presentation (FDR≤0.05). Several of the inflammatory cytokine signatures showed modest inverse relations with signatures of immune checkpoint markers (ρ=-0.3 to -0.4). Women who reported current use of estrogen only MHT had higher expression of CTLA4 in ER-positive breast tumors. For normal-adjacent tissues of ER-positive tumors, parity was associated with higher CD8+ T cell abundance, higher PDL1 expression and lower cytokine signaling in normal-adjacent tissues at p≤0.05; while breastfeeding was associated with lower abundance of CD8+ T cell and higher expression of cytokine signaling in normal-adjacent tissues of ER-negative tumors (p≤0.05). None of the associations in normal-adjacent tissues met FDR significance. The associations between other reproductive factors and immune cell profiles were in general weak. Conclusions: Our study suggests pre-diagnostic reproductive factors may influence breast tumor immune profiles. Future studies are needed to validate these results. Citation Format: Cheng Peng, Yuxi Liu, Yujing Heng, Clara Bodelon, Daniel Stover, Wendy Y. Chen, Michelle D. Holmes, A. Heather Eliassen, Peter Kraft, Rulla M. Tamimi. The impact of reproductive factors on breast tumor and normal-adjacent tissue immune profile from menarche to menopause [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C011.

Unleashing the potential of Genistein and its derivatives as effective therapeutic agents for breast cancer treatment.

Breast cancer remains one of the leading causes of cancer-related deaths among women worldwide. Genistein (Gen), a phytoestrogen soy isoflavone, has emerged as a promising agent in the prevention and treatment of breast cancer due to its ability to function as a natural selective estrogen receptor modulator (SERM). This review explores the multifaceted mechanisms through which Gen and its derivatives exert their anticancer effects, including modulation of the PI3K/Akt signaling pathway, regulation of apoptosis, inhibition of angiogenesis, and impacts on DNA methylation and enzyme functions. We discuss the dual roles of Gen in both enhancing and inhibiting estrogen receptor (ER)-dependent pathways., highlighting its complex interactions with ERα and ERβ. Furthermore, the review examines the synergistic effect of combining Gen with conventional chemotherapeutic agents such as doxorubicin, cisplatin, and selenium, as well as other natural compounds like lycopene. Clinical studies suggest that while isoflavones may not significantly influence breast cancer progression in general, the high consumption of soy isoflavones is associated with reduced recurrence rates in breast cancer survivors. Importantly, Gen's ability to modulate key signaling pathways and enhance the efficacy of existing treatments improves its potential as a valuable adjunct in breast cancer therapy. In conclusion, Gen and its derivatives offer a novel and promising approach for treatment of breast cancer. Continued research into their mechanisms of action and clinical applications will be essential in optimizing their therapeutic potential and translating these findings into effective clinical interventions.

Case series of pure mucinous breast carcinoma: A rare histopathological subtype

Pure mucinous breast carcinoma (PMBC) is even rarer and accounts for about 2% of all primary breast carcinoma. It is composed entirely of tumour cells with abundant extracellular mucin and without admixing of infiltrating ductal carcinoma. We studied a total of ten cases of Pure Mucinous Breast Carcinoma. Here we describes each case of demographic features and histopathological features of PMBC. The results of immunohistochemistry of Estrogen receptor (ER), Progesterone receptor (PR), Human epidermal growth factor receptor 2(HER-2neu) were also noted in this case series. All the cases were female and above 50 years of age. Out of 10 cases, 6 cases have the tumour’s location on the left side of the breast and 4 cases have the tumour’s location on the right side of the breast. All the cases belong to the lower grading and staging of the tumour. Only one case had positive lymph node status.Hormone receptor status of all the cases has ER & PR positive expression, HER-2neu negative expression and low Ki 67 labelling index. To conclude, PMBC was associated with lower-grade tumours, lower-stage, infrequent lymph node metastasis and luminal type A hormonal receptor status. These favourable findings suggest that PMBC has a better prognosis and may give a better response to hormonal therapy.

Insulin-like growth factor-binding protein-3 is induced by tamoxifen and fulvestrant and modulates fulvestrant response in breast cancer cells

IntroductionInsulin-like growth factor binding protein-3 (IGFBP-3) exerts varying effects on estrogen receptor alpha (ERα)-positive and triple-negative breast cancer (TNBC) cells. In ERα-positive cells, IGFBP-3 is antiproliferative and proapoptotic. In contrast, IGFBP-3 stimulates proliferation in triple-negative breast cancer (TNBC) cells via EGFR activation.MethodsTo identify potential mechanisms that underlie the opposing effects of IGFBP-3 on these two breast cancer subtypes, IGFBP-3 expression was determined in cell line models of both ERα-positive breast cancer and TNBC, and cells were treated with antiestrogens tamoxifen and fulvestrant. Results and discussionMCF-7 and T-47D cells expressed low levels of IGFBP-3 when compared to MDA-MB-231 and MDA-MB-468 cells. MCF-7 cells with acquired resistance to the selective estrogen receptor degrader fulvestrant expressed high IGFBP-3 and MCF-7 cells with constitutive IGFBP-3 expression were fulvestrant resistant. IGFBP-3 expression was increased in all cell lines upon treatment with fulvestrant or the selective estrogen receptor modulator tamoxifen and both fulvestrant and tamoxifen increased TNBC cell proliferation. Further, IGFBP-3 expression was increased by treatment with the GPER1 agonist G-1 and attenuated upon treatment with P17, a YAP/TAZ inhibitor. These data suggest that IGFBP-3 modulates breast cancer cells and is a mediator of breast cancer cell response to fulvestrant and tamoxifen.

Cell-cycle machinery is critical in regulating uterine steroid hormone for embryo implantation and development.

Proper embryo implantation is necessary for a successful pregnancy. In this issue of the JCI, Aljubran et al. identified the cell cycle regulatory protein cyclin A2 (CCNA2) as a factor in supporting embryo implantation and embryo development. Endometrial stromal cells showed higher levels of CCNA2 in patients undergoing assisted reproductive technology who had successful pregnancies. CCNA2 expression correlated with stromal cell proliferation and the expression of steroid hormone receptors for estrogen (ESR1, also known as ERα) and progesterone (PGR). Notably, loss of Ccna2 in mouse models resulted in infertility. The uteri of these mice were hypoplastic with reduced estrogen sensitivity, resulting in the disruption of stroma cell decidualization and loss of embryo viability after implantation. These findings demonstrate the importance of stroma cell proliferation in preparing the uterus for embryo implantation. They also identify CCNA2 as a coregulator of steroid hormone receptor signaling and suggest that impaired uterine stroma can underly early pregnancy loss.

Regulatory mechanisms of steroid hormone receptors on gene transcription through chromatin interaction and enhancer reprogramming.

Regulation of steroid hormone receptors (SHRs) on transcriptional reprogramming is crucial for breast cancer progression. SHRs, including estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), and glucocorticoid receptor (GR) play key roles in remodeling the transcriptome of breast cancer cells. However, the molecular mechanisms by which SHRs regulate chromatin landscape in enhancer regions and transcription factor interactions remain largely unknown. In this review, we summarized the regulatory effects of 3 types of SHRs (AR, PR, and GR) on gene transcription through chromatin interactions and enhancer reprogramming. Specifically, AR and PR exhibit bi-directional regulatory effects (both inhibitory and promoting) on ER-mediated gene transcription, while GR modulates the transcription of pro-proliferation genes in ER-positive breast cancer cells. In addition, we have presented four enhancer reprogramming mechanisms (transcription factor cooperation, pioneer factor binding, dynamic assisted loading, and tethering) and the multiple enhancer-promoter contact models. Based on these mechanisms and models, this review proposes that the combination of multiple therapy strategies such as agonists/antagonists of SHRs plus endocrine therapy and the adoption of the latest sequencing technologies are expected to improve the efficacy of ER positive breast cancer treatment.

Survival outcomes for HER2-low breast cancer: Danish national data.

We investigated the prognosis of breast cancer (BC) with low expression of human epidermal growth factor receptor 2 (HER2), as previous studies have found varying impacts on survival of HER2-low BC compared with HER2 0 BC (HER2 IHC score of 0). HER2-low is defined as a score of 1+ or 2+ in an immunohistochemical (IHC) assay without HER2 gene amplification. Patients with HER2 0 or HER2-low BC from the national Danish Breast Cancer Group database were examined by multivariable survival analysis in a retrospective noninterventional investigation. Patients were grouped as either HER2 0 or HER2-low. The primary endpoint was time to recurrence (TR), and the secondary endpoints were overall survival (OS) and distant recurrence-free interval (DRFI). 41,610 patients were included (12,981 with HER2 0 BC and 28,629 with HER2-low BC). HER2-low BC was associated with a lower risk of recurrence (hazard ratio [HR]: 0.92, p = 0.03). Regarding secondary endpoints, HER2-low disease was linked to improved overall OS (HR: 0.94, p = 0.02). No statistically significant effect of HER2-low was found for DRFI, along with no differential effect of HER2-low according to estrogen receptor (ER) status. HER2-low BC was found to show an improved HR for OS and DRFI compared with HER2 0 BC; however, further studies are need to establish whether it represents a separate biological entity.

Aptamer Proteolysis-Targeting Chimeras (PROTACs): A Novel Strategy to Combat Drug Resistance in Estrogen Receptor α-Positive Breast Cancer

Aptamer Proteolysis-Targeting Chimeras (PROTACs): A Novel Strategy to Combat Drug Resistance in Estrogen Receptor α-Positive Breast Cancer

Evidence that CRISPR-Cas9 Y537S-mutant expressing breast cancer cells activate Yes-associated protein 1 to driving the conversion of normal fibroblasts into cancer-associated fibroblasts.

Endocrine therapy (ET) has improved the clinical outcomes of Estrogen receptor alpha-positive (ERɑ +) breast cancer (BC) patients, even though resistance to ET remains a clinical issue. Mutations in the hormone-binding domain of ERɑ represent an acquired intrinsic mechanism of ET resistance. However, the latter also depends on the multiple functional interactions between BC cells and the tumor microenvironment (TME). Here, we investigated how the most common Y537S-ERɑ mutation may influence the behavior of fibroblasts, the most prominent component of the TME. We conducted coculture experiments with normal human foreskin fibroblasts BJ1-hTERT (NFs), cancer-associated fibroblasts (CAFs), isolated from human BC specimens, and Y537S CRISPR-expressing MCF-7 BC cells (MCF-7YS). Mass spectrometry (MS) and Metacore analyses were performed to investigate how the functional interactions between BC cells/fibroblasts may affect their proteomic profile. The impact of fibroblasts on BC tumor growth and metastatic potential was evaluated in nude mice. Mutant BC conditioned medium (CM) affected the morphology/proliferation/migration of both NFs and CAFs. 198 deregulated proteins signed the proteomic similarity profile of NFs exposed to the YS-CM and CAFs. Among the upregulated proteins, Yes-associated protein 1 (YAP1) was the main central hub in the direct interaction network. Increased YAP1 protein expression and activity were confirmed in NFs treated with MCF-7YS-CM. However, YAP1 activation appears to crosstalk with the insulin growth factor-1 receptor (IGF-1R). Higher amount of IGF-1 were noticed in the MCF-7YS-CM cells compared to the MCF-7P, and IGF-1 immunodepletion reversed the enhanced YAP1 expression and activity. Mutant cells upon exposure to the NF- and CAF-CM exhibited an enhanced proliferation/growth/migration/invasion compared to the MCF-7P. MCF-7YS cells when implanted with CAFs showed an early relative increased tumor volume compared to YS alone. No changes were observed when MCF-7P cells were co-implanted with CAFs. Compared with that in MCF-7P cells, the metastatic burden of MCF-7YS cells was intrinsically greater, and this effect was augmented upon treatment with NF-CM and further increased with CAF-CM. YS mutant BC cells induced the conversion of fibroblasts into CAFs, via YAP, which represent a potential therapeutic target which interrupt the functional interactions between mutant cells/TME and to be implemented in the novel therapeutic strategy of a subset of metastatic BC patients carrying the frequent Y537S mutations.

Multifunctional acyltransferase HBO1: a key regulatory factor for cellular functions.

HBO1, also known as KAT7 or MYST2, is a crucial histone acetyltransferase with diverse cellular functions. It typically forms complexes with protein subunits or cofactors such as MEAF6, ING4, or ING5, and JADE1/2/3 or BRPF1/2/3, where the BRPF or JADE proteins serve as the scaffold targeting histone H3 or H4, respectively. The histone acetylation mediated by HBO1 plays significant roles in DNA replication and gene expression regulation. Additionally, HBO1 catalyzes the modification of proteins through acylation with propionyl, butyryl, crotonyl, benzoyl, and acetoacetyl groups. HBO1 undergoes ubiquitination and degradation by two types of ubiquitin complexes and can also act as an E3 ubiquitin ligase for the estrogen receptor α (ERα). Moreover, HBO1 participates in the expansion of medullary thymic epithelial cells (mTECs) and regulates the expression of peripheral tissue genes (PTGs) mediated by autoimmune regulator (AIRE), thus inducing immune tolerance. Furthermore, HBO1 influences the renewal of hematopoietic stem cells and the development of neural stem cells significantly. Importantly, the overexpression of HBO1 in various cancers suggests its carcinogenic role and potential as a therapeutic target. This review summarizes recent advancements in understanding HBO1's involvement in acylation modification, DNA replication, ubiquitination, immunity, and stem cell renewal.

Abstract B014: Prospective analysis of circulating tumor cell dynamics during preoperative radiotherapy in locally advanced breast cancer

Abstract Introduction: This is a per-protocol interim analysis of circulating tumor cell (CTC) dynamics among patients diagnosed with locally advanced breast cancer receiving preoperative radiotherapy (RT) on the TOPAz trial (“Trial of Preoperative Radiation”) with concurrent enrollment on a prospective observational cohort study (2022-0601). Methods: Eligible patients with clinical or pathologic T3-4 or node-positive non-metastatic breast cancer were prospectively enrolled. All patients received preoperative RT followed by mastectomy and were randomized to conventional fractionation (CFx, 50Gy/25Fx) versus hypofractionation (HFx, 40Gy/15Fx). CTCs were enumerated using the CellSearch® assay immediately prior to RT (Pre-RT) and within 1 week of completing RT (End of RT). Rates of CTC detection and clearance with RT were calculated. Results: As of August 2024, 46 enrolled patients had a Pre-RT assessment for CTCs, of which 45 (98%) received neoadjuvant chemotherapy (NAC), 30 (65%) had clinical T3-4 disease, 10 (22%) had advanced nodal (cN3) disease, 39 (85%) had estrogen receptor (ER)- positive disease, 3 (7%) overexpressed Her2, and 6 (13%) had triple negative disease. Prior to RT, 15 (33%) patients had ≥1 detectable CTC (median [IQR] = 2 cells [1-2.5]). Of the 14 CTC- positive patients with a completed “End of RT” blood draw to date, 11 (79%) achieved CTC clearance, while 3 patients had persistent CTCs (median [IQR] = 2 cells [1.5-2.5]). Patients who achieved CTC clearance had significantly lower median initial CTC count compared to patients who had persistent CTCs ((2 [1-2]) versus 8 [5-19], Kruskal-Wallis test, p<0.05). CTC status at either time point was not significantly associated with clinicopathologic or treatment variables. Of the 9 CTC-positive patients who achieved CTC clearance and completed surgery, 1 experienced pCR (11%) while all 3 patients with persistent CTCs had residual disease. The median RCB index score for patients without detectable CTCs at End of RT (n=33) was 2.9 [1.4- 3.4] versus 3.3 [2.2-3.4] for the 3 patients with persistent CTCs. In a subgroup of 37 patients with ER+ Her2- disease, 11 (30%) patients had detectable CTCs prior to RT. Of the 10 with completed “End of RT” blood draw to date, 8 (80%) achieved CTC-clearance. The median RCB index score for patients without detectable CTCs at End of RT (n=27) was 3.0 [1.5-3.6] versus 3.4 [3.4-3.4] for the 2 patients with persistent CTCs. Conclusion: In this prospective analysis of CTC dynamics during preoperative RT for patients with locally advanced breast cancer, one- third of patients had detectable CTCs prior to RT (33%). Following comprehensive RT, 79% of patients with detectable CTCs prior to RT experienced CTC clearance prior to surgical resection. All patients with persistent CTCs had residual disease at surgery. These interim results support further study of longitudinal monitoring of circulating tumor material as a potential real-time biomarker for residual locoregional disease in the preoperative setting. Citation Format: Chelain R Goodman, Simona F Shaitelman, Saleh Ramezani, Jonathan B. Strauss, Anam Zia, Nathan Comeaux, Ritupreet Virk, Ruitao Lin, Kevin Nead, Melissa P Mitchell, Karen E Hoffman, Eric Strom, Michael Stauder, George Perkins, Valerie Reed, Elizabeth Bloom, Melissa Joyner, Pamela Schlembach, Vicente Valero, Bora Lim, Carlos H Barcenas, Anthony Lucci, Wendy A Woodward, Benjamin D Smith. Prospective analysis of circulating tumor cell dynamics during preoperative radiotherapy in locally advanced breast cancer [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr B014.

The novel estrogen receptor beta agonist EGX358 and APOE genotype influence memory, vasomotor, and anxiety outcomes in an Alzheimer’s mouse model

IntroductionAlzheimer’s disease (AD) prevalence and severity are associated with increased age, female sex, and apolipoprotein E4 (APOE4) genotype. Although estrogen therapy (ET) effectively reduces symptoms of menopause including hot flashes and anxiety, and can reduce dementia risk, it is associated with increased risks of breast and uterine cancer due to estrogen receptor alpha (ERβ)-mediated increases in cancer cell proliferation. Because ERβ activation reduces this cell proliferation, selective targeting of ERβ may provide a safer method of improving memory and reducing hot flashes in menopausal women, including those with AD. APOE genotype influences the response to ET, although it is unknown whether effects of ERβ activation vary by genotype.MethodsHere, we tested the ability of long-term oral treatment with a novel highly selective ERβ agonist, EGX358, to enhance object recognition and spatial recognition memory, reduce drug-induced hot flashes, and influence anxiety-like behaviors in female mice expressing 5 familial AD mutations (5xFAD-Tg) and human APOE3 (E3FAD) or APOE3 and APOE4 (E3/4FAD). Mice were ovariectomized at 5 months of age and were then treated orally with vehicle (DMSO) or EGX358 (10 mg/kg/day) via hydrogel for 8 weeks. Spatial and object recognition memory were tested in object placement (OP) and object recognition (OR) tasks, respectively, and anxiety-like behaviors were tested in the open field (OF) and elevated plus maze (EPM). Hot flash-like symptoms (change in tail skin temperature) were measured following injection of the neurokinin receptor agonist senktide (0.5 mg/kg).ResultsEGX358 enhanced object recognition memory in E3FAD and E3/4FAD mice but did not affect spatial recognition memory. EGX358 also reduced senktide-induced tail temperature elevations in E3FAD, but not E3/4FAD, females. EGX358 did not influence anxiety-like behaviors or body weight.DiscussionThese data indicate that highly selective ERβ agonism can facilitate object recognition memory in both APOE3 homozygotes and APOE3/4 heterozygotes, but only reduce the magnitude of a drug-induced hot flash in APOE3 homozygotes, suggesting that APOE4 genotype may blunt the beneficial effects of ET on hot flashes. Collectively, these data suggest a potentially beneficial effect of selective ERβ agonism for memory and hot flashes in females with AD-like pathology, but that APOE genotype plays an important role in responsiveness.

Lower FGFR2 mRNA Expression and Higher Levels of FGFR2 IIIc in HER2-Positive Breast Cancer

Fibroblast growth factor receptor 2 (FGFR2) has been associated with breast cancer. We performed in silico analyses to investigate the FGFR2 mRNA expression and splice variants associated with breast cancer subtypes. Online databases, including cBioPortal and TCGA SpliceSeq, were used to examine the association between the FGFR2 expression and splice variants with breast cancer subtypes. A higher FGFR2 mRNA was significantly associated with luminal, oestrogen receptor (ER)-positive breast cancers, and invasive lobular carcinomas, whereas a lower FGFR2 was associated with human epidermal growth factor receptor 2 (HER2)-positive breast cancer and invasive ductal carcinomas. The epithelial alternatively spliced FGFR2 IIIb isoform was significantly enriched in ER+ breast cancer, while the mesenchymal FGFR2 IIIc isoform was significantly prevalent in HER2+ cancer. Increased levels of FGFR2 and IIIb splice isoforms are associated with less aggressive breast cancer phenotypes, while decreased levels of FGFR2 and increased IIIc splice isoform are associated with more aggressive phenotypes.

Prediction of genetic profile of breast carcinoma on MRI using a combination of DCE‐MRI, DWI, and MR spectroscopy: A prospective observational study

AbstractBackgroundClassification of breast cancer based on gene expression has emerged as the standard approach in its management, owing to the distinct prognoses and treatment responses observed among different subtypes. The aim of this study was to prospectively assess the imaging features of the molecular subtypes of breast cancer using multiparametric magnetic resonance imaging (mMRI) with the combined assessment of dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI), diffusion‐weighted imaging (DWI), and MR spectroscopy (MRS).MethodsThis was a prospective observational single‐center cohort study, which included women with BI‐RADS 4−5 lesions on mammography/ultrasound (US) who subsequently underwent 1.5 T MRI (encompassing DCE‐MRI, DWI, and MRS). The histological subtypes of breast cancer were assessed. Estrogen receptor (ER), progesterone receptor (PR), Ki‐67 status, and human epidermal growth receptor‐2 (HER2) expression, assessed by immunohistochemistry (IHC), defined four molecular subtypes: luminal A, luminal B, HER2‐enriched (Her2en), and triple‐negative breast carcinoma (TNBC). Statistical associations between the four molecular subtypes and MRI features were investigated.ResultsFifty patients were included in the study. Circumscribed margins were significantly correlated with triple‐negative tumors compared to others (78% versus 6%, p < 0.001). Spiculated margins were observed in non‐triple negative tumors. Rim enhancement was significantly correlated to triple‐negative tumors compared to all other subtypes (71.4% versus 25%, p = 0.035). Mean apparent diffusion coefficient (ADC) values were significantly lower for luminal subtypes compared to non‐luminal subtypes (p < 0.001). The total choline (tCho) signal‐to‐noise ratio (SNR) was higher in triple‐negative tumors. A combined algorithm using DCE‐MRI, DWI, and MRS can predict TNBC and Her2en with specificity of 86.6% and 100%, respectively, and sensitivity of 100% and 85.37%, respectively.ConclusionThe combination of mMRI with DCE‐MRI, DWI, and MRS can accurately differentiate the molecular subtypes of breast carcinoma.

Primary Osteoporosis Induced by Androgen and Estrogen Deficiency: The Molecular and Cellular Perspective on Pathophysiological Mechanisms and Treatments

Primary osteoporosis is closely linked to hormone deficiency, which disrupts the balance of bone remodeling. It affects postmenopausal women but also significantly impacts older men. Estrogen can promote the production of osteoprotegerin, a decoy receptor for RANKL, thereby preventing RANKL from activating osteoclasts. Furthermore, estrogen promotes osteoblast survival and function via activation of the Wnt signaling pathway. Likewise, androgens play a critical role in bone metabolism, primarily through their conversion to estrogen in men. Estrogen deficiency accelerates bone resorption through a rise in pro-inflammatory cytokines (IL-1, IL-6, TNF-α) and RANKL, which promote osteoclastogenesis. In the classic genomic pathway, estrogen binds to estrogen receptors in the cytoplasm, forming a complex that migrates to the nucleus and binds to estrogen response elements on DNA, regulating gene transcription. Androgens can be defined as high-affinity ligands for the androgen receptor; their combination can serve as a ligand-inducible transcription factor. Hormone replacement therapy has shown promise but comes with associated risks and side effects. In contrast, the non-genomic pathway involves rapid signaling cascades initiated at the cell membrane, influencing cellular functions without directly altering gene expression. Therefore, the ligand-independent actions and rapid signaling pathways of estrogen and androgen receptors can be harnessed to develop new drugs that provide bone protection without the side effects of traditional hormone therapies. To manage primary osteoporosis, other pharmacological treatments (bisphosphonates, teriparatide, RANKL inhibitors, sclerostin inhibitors, SERMs, and calcitonin salmon) can ameliorate osteoporosis and improve BMD via actions on different pathways. Non-pharmacological treatments include nutritional support and exercise, as well as the dietary intake of antioxidants and natural products. The current study reviews the processes of bone remodeling, hormone actions, hormone receptor status, and therapeutic targets of primary osteoporosis. However, many detailed cellular and molecular mechanisms underlying primary osteoporosis seem complicated and unexplored and warrant further investigation.

Novel Nordaucane Sesquiterpenoid and Sesquiterpene Lactone From Laserpitium Species: Isolation, Structure Elucidation, InVitro, InVivo, and In Silico Evaluation as Anticancer Agents.

This study explores the cytotoxic activity-guided isolation of the underground parts of Laserpitium hispidum M. Bieb and Laserpitium petrophilum Boiss. & Heldr., which have not been previously investigated. The aim is to isolate and evaluate bioactive compounds from Laserpitium L. species with anticancer potential. This study involves bioactivity-guided isolation and structural studies of the pure compounds utilizing NMR, UV-Vis, IR spectroscopies, and HRMS. The cytotoxic activity of the isolated compounds was evaluated invitro and invivo, whereas molecular modeling, docking, and ADME predictions were conducted using Schrödinger software. The study isolated phenylpropanoids (laserine (1), latifolone (2), myristicin (3)), sterol (stigmasterol (4)), polyenes (falcarindiol (5)), sesquiterpene lactone (11-hydroxybadkhyzin (6)), and nordaucane sesquiterpene (norlasidiol angelate (7)) from L. hispidum, whereas L. petrophilum yielded 10β-acetoxy-8α-angeloyloxy-6αH,7αH-guaian-3-en-12,6-olide (8), 10β-acetoxy-8α-senecioyloxy-6αH,7αH-guaian-3-en-6,12-olide (9) and acetylisomontanolide (10). Molecular docking simulations revealed stable interactions between compounds 7 and 9 with estrogen receptor α (ERα) and vascular endothelial growth factor receptor 2 (VEGFR2), with compound 7 showing superior stability and binding affinity. In silico ADME predictions indicated favorable pharmacokinetic properties, including high oral absorption. Compounds 7 and 9, representing new nordaucane and sesquiterpene lactones, have not been previously reported. Invitro cytotoxicity revealed that compound 7 exhibits potent anti-cancer activity against MCF-7 cells, whereas compound 9 showed reduced cytotoxicity. Invivo testing in Caenorhabditis elegans supported these findings, suggesting safety and efficacy in organisms. In silico results emphasize the potential of these compounds, with compound 7 promising due to its stability and strong binding affinity.