Hormone-responsive Breast Cancer Research Articles

Virtual Screening of Apigenin and Luteolin as Natural Aromatase Inhibitors for the Treatment of Breast Cancer Patients

Aromatase is an enzyme that converts androgens (like testosterone) to estrogens (like 17- estradiol). It is also a highly successful therapeutic target for endocrine-responsive breast cancer. Aromatase inhibitors, which suppress estrogen synthesis in postmenopausal women, have been useful in the treatment of individuals with estrogen receptor-positive breast cancer. Anastrozole is an aromatase inhibitor medication that is used in the management and treatment of breast cancer. Flavonoids inhibit cancer cell proliferation by causing apoptosis, encouraging autophagy, and changing the cell cycle. Although several dietary flavonoids (like in parsley, celery and Broccoli) can inhibit aromatase, the tissue specificity and mechanism of binding are uncertain. According to several researches, flavonoids (apigenin and luteolin) dramatically suppress estrogen production. The study aims to examine binding of 3EQM (Aromatase) in the A chain with both of flavonoid (Apigenin and luteolin) and Anastrozole, using an in silico approach. PyRx default program was used to detect docking accuracy. Virtually, results showed that flavonoids have higher binding strength for apigenin and luteolin (which was -8.2 and -8.3) than Anastrozole (which was -7.6) with chain A of Aromatase. So, flavonoids can potentially be used as a natural medication to reduce breast cancer incidence. However, clinical trial studies are needed to investigate the role of apigenin and luteolin in the treatment of breast cancer.

A Randomized Trial Comparing Concurrent versus Sequential Radiation and Endocrine Therapy in Early-Stage, Hormone-Responsive Breast Cancer.

Concerns exist regarding increased toxicities, including endocrine therapy toxicity, with concurrent radiation and endocrine therapy in early breast cancer (EBC). We present a pragmatic, randomized trial comparing concurrent versus sequential endocrine and radiotherapy in hormone-responsive EBC. In this multicenter trial, patients were randomized to receive adjuvant endocrine therapy concurrent with, or sequential to, radiotherapy. The primary outcome was change in endocrine therapy toxicity from baseline to 3 months post radiotherapy using the Functional Assessment of Cancer Therapy-Endocrine Symptom (FACT-ES) score. From September 2019 to January 2021, 133 patients were randomized to concurrent endocrine and radiotherapy, and 127 to sequential treatment. Most patients were post-menopausal (72.7%, 189/260) with stage 1 disease (65.8%, 171/260). Tamoxifen was the endocrine therapy of choice for 69.6% (181/260) of patients, and an aromatase inhibitor for the remainder. The median total radiation dose and fractions were 40.1 Gray (range 26-50) and 15 fractions (range 5-25), respectively. For the primary outcome of change in endocrine therapy toxicity per FACT-ES scores from baseline to 3 months post radiotherapy, no significant difference was found between the groups (median [range] = -4.9 (-82, 38.8) for concurrent and -5.1 (-42, 40) for sequential, p = 0.87). This is the first trial to investigate the impact of concurrent versus sequential adjuvant endocrine and radiotherapy on endocrine therapy-related toxicities. The findings provide further support to allow the optimal timing of radiation and endocrine therapy to be tailored for the individual patient.

Longitudinal analysis of circulating tumor cell numbers improves tracking metastatic breast cancer progression

Hormone-responsive breast cancer represents the most common type and has the best prognosis, but still approximately 40% of patients with this type can develop distant metastases, dramatically worsening the patient’s survival. Monitoring metastatic breast cancer (mBC) for signs of progression is an important part of disease management. Circulating tumor cell (CTC) detection and molecular characteristics gain importance as a diagnostic tool, but do not represent a clinical standard and its value as a predictor of progression is not yet established. The main objective of this study was to estimate the prognostic value of not only the CTC numbers, but also the dynamics of the CTC numbers in the same patient during the continuous evaluation of CTCs in patients with advanced breast cancer. The other objective was to assess the molecular changes in CTCs compared to primary tumor samples by genetic analysis of the seven genes associated with estrogen signaling pathway, mutations in which are often responsible for the resistance to endocrine therapy, and subsequent progression. This approach was taken to evaluate if genetic analysis of CTCs can be used in tracking the resistance, signaling that hormonal therapy should be replaced. Consequently, this report presents the results of a longitudinal CTC study based on three subsequent blood collections from 135 patients with metastatic breast cancer, followed by molecular analysis of the isolated single CTCs. CTCs were detected and isolated using an image-based, EpCAM-independent system CytoTrack; this approach allowed evaluation of EpCAM expression in detected CTCs. Isolated CTCs were subjected to NGS analysis to assess mutational changes. The results confirm the importance of the status of the CTC for progression-free survival and overall survival and provide new data on the dynamics of the CTC during a long monitoring period and in relation to clinical progression, highlighting the advantage of constant monitoring over the single count of CTC. Furthermore, high genetic and phenotypic inter- and intrapatient heterogeneity observed in CTCs suggest that metastatic lesions are divergent. High genetic heterogeneity in the matching CTC/primary tumor samples may indicate early dissemination. The tendency towards the accumulation of activating/oncogenic mutation in CTCs, leading to anti-estrogen resistant disease, was not confirmed in this study.

Mitochondrial calcium overload contributes to cannabinoid-induced paraptosis in hormone-responsive breast cancer cells.

Studies have shown that natural products can induce paraptosis in tumour cell lines. Paraptosis is characterized by cytoplasmic vacuolation arising from the endoplasmic reticulum (ER) and mitochondria. The mechanism of paraptosis is unclear; however, dysregulation of Ca2+ homeostasis is believed to affect paraptosis induction. This study investigated the mechanism of cell death induced by a phytocannabinoid ratio in the MCF7 breast cancer cell line. The crystal violet assay was used to detect changes in viability and morphology changes were investigated using light and transmission electron microscopy. Various inhibitors, fluorescent staining with high-content screening, and Western blot analysis were used to investigate different cell death mechanisms. The phytocannabinoid ratio induced significant cell death and cytoplasmic vacuolation in MCF7 cells; however, no apoptosis, necrosis, autophagy, or ferroptosis was detected. Vacuolation induced by phytocannabinoid treatment was inhibited by cycloheximide, suggesting paraptosis induction. The mechanism of paraptosis induction was investigated, and it was found that treatment (1) induced ER dilation and mitochondrial swelling, (2) induced significant ER stress and mitochondrial Ca2+ overload and dysfunction, which appeared to be mediated by the voltage-dependent anion channel, and (3) significantly impaired all mitochondrial metabolic pathways. The data demonstrated that paraptosis induced by the cannabinoid ratio was mediated by Ca2+ flux from the ER to the mitochondria. These findings highlight a novel mechanism of cannabinoid-induced cell death and emphasize the anti-cancer potential of cannabinoid ratios, which exhibited enhanced effects compared to individual cannabinoids.

Abstract PO2-11-03: A long-term follow-up of patients who interrupted endocrine therapy to become pregnant following breast cancer surgery

Abstract Introduction: Regarding discontinue adjuvant endocrine therapy to attempt pregnancy, Pregnancy Outcome and Safety of Interrupting Therapy for Women with Endocrine Responsive Breast Cancer (POSITIVE) clinical trials have revealed temporary interruption of endocrine therapy to attempt pregnancy did not confer short-term risk of breast cancer events. However, that report involved a short observation period, longer-term follow-up is required. This study was aimed to evaluate the safety of endocrine therapy interruption with long-term followed-up data base. Methods: This was a retrospective study using surveying of medical chart data between June 2007 and November 2015 at St. Luke’s International Hospital. The subjects were 65 patients with estrogen-receptor positive primary breast cancer (clinical stage I-III) who had been performed fertility preservation prior to starting breast cancer treatment. Adjuvant endocrine therapy completion was defined as 120 months (10 years) and discontinuation was defined as < 120 months. Using the definition, we classified the patients into an endocrine therapy interruption-group and a continuation-group. The primary outcome was the breast cancer free interval (BCFI). We defined breast cancer events as local, regional, or distant recurrence of invasive breast cancer or new contralateral invasive breast cancer during follow-up. Results: Median follow-up period was 110 (range, 36–181) months. The number of adjuvant endocrine therapy interruption-group was 30 and continuation-group was 35. Among 65 patient, the mean patient age in the interruption vs. continuation groups were as follows: 38(range, 26-48) years vs. 36.5 (range, 26–45) years at breast cancer diagnosis and HER2 positive breast cancer was identified in 4 (11.4%) vs 4 (13.3%) patients. Clinical stages were Stage I, 9 (30%) vs. 11 (31.4%) patients; Stage II, 18 (60%) vs. 18 (51.4%) patients; and Stage III, 3 (10%) vs. 6 (17.1%) patients. Chemotherapy was administered in 17 (56.7%) and 23 (65.7%) patients, respectively. The median duration of endocrine therapy before interruption was 25.5 months: 3 (10%) patients received endocrine therapy for 0–18 months, 16 (53.3%) for 18–30 months, and 11 (36.7%) for >30 months. The BCFI was 124 and 119 months in the interruption and continuation groups, respectively (p = 0.16). There were 6 (20%) and 9 (25.7%) breast cancer events in the interruption-group and continuation-group, respectively (p = 0.4). All the pregnancies were in the endocrine therapy interruption group (17 pregnancies, 16 deliveries), with one pregnancy involving the delivery of twins. Three pregnancies were spontaneous. Endocrine therapy was resumed in 16 (59.3%) patients in the interruption-group (median time to resumption, 20.5 months). One patient developed distant metastasis during endocrine therapy interruption period. Conclusion: Among patients who performed fertility preservation prior to starting breast cancer treatment, our long-term follow-up data, almost 9 years, suggested that the BCFI was not statistically different between endocrine therapy interruption-group and continuation-group. A limitation of this study is that only three cases of Stage III breast cancer were included in the interruption group. Therefore, we consider that careful decisions should be made regarding interruption of endocrine therapy. Citation Format: Risa Kasahara, Atsuko Kitano, Fumi Akitani, Kyoko Shiota, Kumiko Kida, Junko Takei, Atsushi Yoshida. A long-term follow-up of patients who interrupted endocrine therapy to become pregnant following breast cancer surgery [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 PO2-11-03.

Association of Chlamydia trachomatis Infection With Breast Cancer Risk and the Modification Effect of IL-12

BackgroundChlamydia trachomatis (C. trachomatis) infection has been implicated in various cancers, yet its association with breast cancer remains unexplored. This infection triggers a cascade of immune responses primarily regulated by Interleukins-12 (IL-12). Thus, the objective of this case-control study was to investigate the link between C. trachomatis infection and breast cancer risk, as well as the modification effect of IL-12. MethodsWe assessed IgG levels against C. trachomatis in serum of 1,121 women with breast cancer (861 with estrogen receptor-positive (ER+) and 260 with estrogen receptor-negative (ER-) tumors) and 400 controls in Guangzhou, China. Logistic regression models were applied to estimate the odds ratios (ORs) and 95% confidence intervals (95% CIs) for breast cancer risk in association with C. trachomatis infection. The interaction between C. trachomatis infection and IL-12 on breast cancer risk was estimated by the product terms in the logistic regression models. ResultsSeropositivity of C. trachomatis IgG showed a slight association with an increased risk of breast cancer (OR = 1.20; 95% CI: 0.86∼1.78). This association was more pronounced among women with a higher (OR = 5.82; 95% CI: 1.31∼25.94) than a lower (OR = 0.73; 95% CI: 0.41∼1.30) level of IL-12, with a statistically significant interaction observed (Pinteraction = 0.013). In addition, C. trachomatis IgG seropositivity was related to an increased risk of breast cancer among PR+ patients (OR = 1.53; 95% CI: 1.04∼2.23). ConclusionsC. trachomatis infection may contribute to the development of hormone-responsive breast cancer in women with high levels of IL-12. Further studies are needed to uncover the underlying mechanisms.

Abstract LB335: Steroid receptor cross-talk in breast cancer

Abstract Breast cancer is the most frequently diagnosed cancer in women worldwide. Oestrogen Receptor-α (ERα), is expressed in two thirds of human breast cancers, and the majority of patients are sensitive to endocrine therapy, i.e. anti-oestrogens or aromatase inhibitors that aim to block oestrogen signalling. In addition to ERα, the other members of the steroid receptor family (androgen, AR; progesterone, PR; glucocorticoid, GR; mineralocorticoid receptors, MR) also appear to play an important role in tumour development and recurrence, but the role of this signalling in cancer progression has not been fully characterised. Therefore, this study aims to address the role of the steroid receptor family members in breast cancer and to assess the effect of downstream signalling upon prognosis. Investigation of receptor signalling cross-talk using reporter, proliferation and migration assays, demonstrated that ERα and the other steroid receptors inhibit each other’s activity in endocrine responsive breast cancer cell lines, MCF7 and T47D. Furthermore, treatment with antioestrogen reversed the suppressive effects of ER𝛼;;; on the activity of the androgen, glucocorticoid progesterone receptors. To characterize receptor crosstalk on a global scale, RNA-seq and ChIP-seq datasets were analysed. Analysis of the ChIP-seq data demonstrated that the PR, GR and AR reprogramming of ERα results in the loss of ERα canonical binding sites and the gain of novel response elements/binding sites. Motif enrichment analysis of the novel ERα binding sites suggested that the altered binding in response to AR, GR and PR signalling, promotes the recruitment of ERα to androgen, glucocorticoid and progesterone response elements, respectively. Gene ontology analysis also revealed that this change in ERα binding sites is correlated with alterations in genes linked to cell proliferation and growth. Moreover, transcriptome studies showed that cotreatment of cells with estradiol and glucocorticoid or mineralocorticoid resulted in the upregulation of apoptotic signalling pathways. These findings may provide an explanation for the observed downregulation of GR and MR expression in ERα positive breast cancer. Patient datasets were used to investigate the prognostic significance of the steroid receptor target genes of interest, more specifically, those deregulated as a result of cross-talk. Considering overall survival and disease specific survival, univariate and multivariate Cox models with Lasso Regression were used to identify prognostic gene signatures using RNA_seq datasets. Kaplan-Meier (KM) and ROC analyses were applied to evaluate risk models. Established genetic markers associated with MR, AR, GR and PR was used to stratify BC patients into low and high risk groups. Patients survival was found to be positively correlated with these signatures, demonstrates that these gene sets have prognostic value. Further studies are required to validate these preliminary results to understand the role of steroid receptor crosstalk in breast cancer formation, progression, and survival. Citation Format: Aygun Azadova, Greg Brooke, Antonio Marco. Steroid receptor cross-talk in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB335.

Abstract 4692: A novel ceramide synthase 2 agonist and its implication in triple-negative breast cancer therapy

Abstract Based on the biological/molecular markers, breast cancer can be classified into five subgroups: Luminal A (ER+/PR+/HER2-), Luminal B (ER+/PR-/HER2- or ER+/PR+/HER2+, triple-positive), ER-/PR-/HER2+, and ER-/PR-/HER2- (triple-negative). Significant progress has been made in treating hormone-responsive and HER2-expressing breast cancer. However, the targeted therapies are limited for triple-negative breast cancer (TNBC) due to lack of well-defined druggable targets. Additionally, all breast cancer subtypes can quickly develop resistance to current treatments. Thus, there is an urgent need for therapeutic strategies targeting pathways common to all subtypes, irrespective of receptor status. In this effort, we have synthesized a novel biisoquinoline-derivative, DH20931 (US Patent ID: US9914733B2) that induces cytotoxicity in breast cancer cells, including TNBC cells. The spatial molecular modeling and enzymatic assays show that DH20931 interacts with and stimulates ceramide synthase 2 (CerS2) activity, reduces the growth of hormone-responsive, HER2-expressing, and TNBC cells in monolayer and 3D spheroid culture models. DH20931 treatment increases the level of very long chain fatty acid (VLCFA) containing ceramides, induces lipotoxic endoplasmic reticulum (ER) stress, and ATF4/CHOP/PUMA pathway of apoptosis. Based on Swiss-ADME analysis, DH20931 possess all the properties of a druggable molecule and obeys the Lipinski-rule-of-five. Thus, DH20931 can be developed as a novel targeted therapeutic agent independent of ER, PR and HER2 status that potentially may reduce the morbidity and mortality for women with breast cancer. Citation Format: Hissah Alatawi, Nayeong Koo, Iqbal Mahmud, Haritha Nair, Amandeep Singh, Timothy J. Garrett, Arun K. Sharma, Sukwon Hong, Satya Narayan. A novel ceramide synthase 2 agonist and its implication in triple-negative breast cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4692.

Benefits and limitations of breastfeeding for mothers
 with malignant tumors

In the modern world breastfeeding (BF) is considered as a significant factor in reducing the risk of developing malignant tumors of the mammary gland and ovaries. However, the problem of maintenance or refusing BF in malignant neoplasms (malignant neoplasms) still remains open. In recent years, there has been a steady increase in breast cancer (BC), especially in developed countries, with more than 10% of all breast malignancies (BC) diagnosed in women under 40 years of age. The presented article highlights aspects of maintaining lactation in different periods of the relevance of BF in relation to the timing of manifestation of cancer, and also presents data from the multicenter study POSITIVE (Pregnancy Outcome and Safety of Interrupting Therapy for women with endocrine responsIVE breast cancer) on the possibilities of implementing reproductive function and BF in women receiving therapy for hormone-receptor positive (HR+) BC stages I–III. BF with cancer detected in the postpartum period depends on the treatment of the underlying disease. In patients undergoing surgical treatment, BF is not contraindicated, but it is not always technically possible. During chemotherapy, BF is not recommended. When carrying out radiotherapy, it is possible to undergo BF using a healthy mammary gland. There is currently no evidence to suggest that BF woman diagnosed with cancer may have any negative effects. In general, it has been shown that preserving and maintaining lactation in women with a history of cancer is safe for both mother and child.

A progesterone derivative linked to a stable phospholipid activates breast cancer cell response without leaving the cell membrane

In hormone-responsive breast cancer cells, progesterone (P4) has been shown to act via its nuclear receptor (nPR), a ligand-activated transcription factor. A small fraction of progesterone receptor is palmitoylated and anchored to the cell membrane (mbPR) forming a complex with estrogen receptor alpha (ERα). Upon hormone exposure, either directly or via interaction with ERα, mbPR activates the SRC/RAS/ERK kinase pathway leading to phosphorylation of nPR by ERK. Kinase activation is essential for P4 gene regulation, as the ERK and MSK1 kinases are recruited by the nPR to its genomic binding sites and trigger chromatin remodeling. An interesting open question is whether activation of mbPR can result in gene regulation in the absence of ligand binding to intracellular progesterone receptor (iPR). This matter has been investigated in the past using P4 attached to serum albumin, but the attachment is leaky and albumin can be endocytosed and degraded, liberating P4. Here, we propose a more stringent approach to address this issue by ensuring attachment of P4 to the cell membrane via covalent binding to a stable phospholipid. This strategy identifies the actions of P4 independent from hormone binding to iPR. We found that a membrane-attached progestin can activate mbPR, the ERK signaling pathway leading to iPR phosphorylation, initial gene regulation and entry into the cell cycle, in the absence of detectable intracellular progestin.

Abstract IA13: Molecular and genomic mechanisms of estrogen signaling and gene regulation in breast cancer

Abstract Transcriptional enhancers function as nucleation sites for the assembly of transcription-regulating complexes across the genome, which act to drive cell type-specific patterns of gene expression. Although many features of active enhancers [e.g., H3K4me1, H3K27ac, enrichment of p300/CBP and Mediator, and production of enhancer RNAs (eRNAs)] have been defined by genomic assays, the roles of these features in estrogen receptor alpha (ERa) enhancer function are not well understood. We are interested in how the molecular underpinnings of ERa enhancer formation and activity control the gene expression programs that drive breast cancer phenotypes and responses to therapeutic agents. We have used a variety of molecular, biochemical, genomic, genetic, and computational approaches to determine the following aspects of ERa enhancers biology in hormone-responsive breast cancer cells: (1) where ERa enhancers are formed across the genome, (2) the kinetics of ERa enhancer formation and disassembly, (3) the influence of genetic variation on ERa enhancer function, (4) the role of the enhancer features noted above in ERa enhancer function, and (5) how protein complexes and small polypeptides serve as coregulators to drive ERa transcriptional activity. Our current focus has been on eRNAs, which are poorly characterized noncoding RNAs that are thought to regulate enhancer function and gene expression. We have identified a ~40 nucleotide functional eRNA regulatory motif (FERM) present in many estrogen-regulated eRNAs that promotes gene expression by increasing ERα recruitment and stimulating p300-catalyzed H3K27 acetylation. In addition, we have been examining how the dose of estrogen impacts the efficiency of enhancer assembly by ERα. Finally, we have been exploring the role of PARP1, a ubiquitous chromatin-associated regulator, and small polypeptides derived from “non-coding” RNAs, control ERa enhancer function. In all cases, we perform analyses to link enhancer function to gene expression outcomes and breast cancer biology. Collectively, our results demonstrate the biological and mechanistic roles of eRNAs in breast cancer. This work is supported by grants from the NIH/NIDDK (DK058110) and CPRIT (RP160319) to W.L.K. Citation Format: W. Lee Kraus. Molecular and genomic mechanisms of estrogen signaling and gene regulation in breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr IA13.

Phytochemicals from Pterocarpus angolensis DC and Their Cytotoxic Activities against Breast Cancer Cells.

Pterocarpus anglonesis DC is an indigenous medicinal plant belonging to the Pterocarpus genus of the Fabaceae family. It is used to treat stomach problems, headaches, mouth ulcers, malaria, blackwater fever, gonorrhea, ringworm, diarrhea, heavy menstruation, and breast milk stimulation. Column chromatography of the stem bark extracts resulted in the isolation of eight compounds, which included friedelan-3-one (1), 3α-hydroxyfriedel-2-one (2), 3-hydroxyfriedel-3-en-2-one (3), lup-20(29)-en-3-ol (4), Stigmasta-5-22-dien-3-ol (5), 4-O-methylangolensis (6), (3β)-3-acetoxyolean-12-en-28-oic acid (7), and tetradecyl (E)-ferulate (8). The structures were established based on NMR, IR, and MS spectroscopic analyses. Triple-negative breast cancer (HCC70), hormone receptor-positive breast cancer (MCF-7), and non-cancerous mammary epithelial cell lines (MCF-12A) were used to test the compounds' cytotoxicity. Overall, the compounds showed either no toxicity or very low toxicity to all three cell lines tested, except for the moderate toxicity displayed by lupeol (4) towards the non-cancerous MCF-12A cells, with an IC50 value of 36.60 μM. Compound (3β)-3-acetoxyolean-12-en-28-oic acid (7) was more toxic towards hormone-responsive (MCF-7) breast cancer cells than either triple-negative breast cancer (HCC70) or non-cancerous breast epithelial (MCF-12A) cells (IC50 values of 83.06 vs. 146.80 and 143.00 μM, respectively).

Vesicle-Encapsulated Rolipram (PDE4 Inhibitor) and Its Anticancer Activity.

Vesicular carriers of drugs are popular for specific targeting and delivery. The most popular vesicles among these are liposomes. However, they suffer from some inherent limitations. In this work, alternative vesicles with enhanced stability, i.e., niosomes and bilosomes have been prepared, characterized, and their delivery efficiency studied. Bilosomes have the additional advantage of being able to withstand the harsh environment of the gastrointestinal tract (GIT). The taurine-derived bile salt (NaTC) was incorporated into the bilosome bilayer. The inspiration behind NaTC insertion is the recent reports on antiaging action and immune function of taurine. Fluorescence probing was used to study the vesicle environment. The entrapment and subsequent release of the important cAMP-specific PDE4 inhibitor/drug Rolipram, which has antibreast cancer properties, was assessed on the breast cancer cell line MCF-7. Rolipram has important therapeutic applications, one of the most significant in recent times being the treatment of Covid-19-triggered pneumonia and cytokine storms. As for cancer chemotherapy, the localization of drug, targeted delivery, and sustained release are extremely important issues, and it seemed worthwhile to explore the potential of the bilosomes and niosomes to entrap and release Rolipram. The important finding is that niosomes perform much better than bilosomes in the hormone-responsive breast cancer mileau MCF-7. Moreover, there was a 4-fold decrease in the IC50 of Rolipram encapsulated in niosomes compared to Rolipram alone. On the other hand, bilosome-encapsulated Rolipram shows higher IC50 value. The results can be further understood by molecular docking studies.

Association of androgen receptor and tumour-infiltrating lymphocytes with bone recurrence in triple-negative breast cancer

BackgroundAs compared to endocrine responsive breast cancer bone is less frequent site of distant recurrence in triple-negative breast cancer (TNBC). A biomarker which predicts bone recurrence would allow a more personalized treatment approach with adjuvant bisphosphonates in TNBC. Here we hypothesised that tumour expression of androgen receptor (AR) is associated with bone recurrence in TNBC. Materials and methodsPatients with operable TNBC who were treated at the Institute of Oncology Ljubljana between 2005 and 2015 and developed distant recurrence were included into our study. Nuclear expression of AR in the tissue of primary tumours was determined immunohistochemically by using the Androgen Receptor (SP107) Rabbit Monoclonal Antibody. We applied a logistic regression model to test the association between expression of AR and development of bone metastases. The model was adjusted for selected known prognostic factors and possible confounders in TNBC, including the level of the stromal tumour-infiltrating lymphocytes (sTILs). ResultsAt recurrence 45 (45 %) out of 100 patients presented with bone metastases. Additionally, seven (7 %) developed bone metastases metachronously. AR was expressed in primary tumours of 35 (35 %) women and 19 (54.3 %) developed bone recurrence. In 25 (25 %) patients sTILs were absent. Neither the proportion of AR positive cancer cells (OR = 1.00; 95 % CI 0.96–1.03; p = 1.00) nor the intensity of AR positive reaction (OR = 0.71; 95 % CI 0.02–21.4; p = 1.00) were significantly associated with bone recurrence. However, women with at least mild level of the sTILs were at significantly lower risk for bone recurrence as compared to those without any sTILs (OR = 0.01; 95 % CI < 0.01–0.08; p = 0.01). ConclusionsExpression of AR is not significantly associated with the development of bone metastases in TNBC. However, patients with absent sTILs in their primary tumours are highly susceptible for recurrence in the bone and might particularly benefit from adjuvant bisphosphonates.

Unlocking the potential of aromatase inhibitors: recent advances in drug design, synthesis, docking activity, and in vitro bioactivity evaluations

Breast cancer, a global health concern claiming approximately 685,000 lives in 2020, necessitates continual advancements in therapeutic strategies. Estrogen and aromatase play pivotal roles in hormone-responsive breast cancer, with 80% of patients exhibiting estrogen receptor-positive tumors. Aromatase inhibitors (AIs), notably non-steroidal inhibitors like anastrozole and letrozole, have significantly improved outcomes, yet challenges persist, including side effects. This review focuses on recent developments in AIs, exploring xanthone derivatives, imidazole derivatives, and curcumin derivatives as potential inhibitors of aromatase. Molecular docking studies, employing Auto Dock and other tools, reveal the binding affinities and interactions of these compounds with the aromatase enzyme. Among xanthones, Erythrommone emerges as a potent inhibitor, holding promise for clinical trials. Imidazole derivatives, synthesized through the Debus-Radziszewski reaction, demonstrate anticancer potential, with compounds like 1a exhibiting superior efficacy against MCF7 cells. ADME-Tox analyses indicate promising drug-likeness but reveal potential mutagenic effects and environmental impacts. Curcumin derivatives, particularly 1,5-diaryl-1,4-pentadien-3-ones, present alternatives to address curcumin's bioavailability challenges. A study of 25 compounds (DKC) identifies DKC-10 as a potent inhibitor, outperforming established breast cancer drugs in terms of binding affinity and interactions with aromatase and ERα+ receptors. These findings underscore the importance of exploring diverse chemical structures in developing AIs, paving the way for more effective and well-tolerated therapeutics. The integration of computational techniques, such as molecular docking studies, accelerates drug discovery by predicting interactions at the molecular level. Overall, this comprehensive review provides valuable insights into the evolving landscape of aromatase inhibitors, offering a roadmap for future research and the development of advanced breast cancer therapeutics.

Genome-wide DNA methylation changes upon DOT1L inhibition in hormone-responsive breast cancer cells

Genome-wide DNA methylation changes upon DOT1L inhibition in hormone-responsive breast cancer cells

Real-world outcomes of patients with metastatic endocrine-responsive breast cancer receiving palbociclib-based combinations.

Aim: To describe treatment journey and clinical outcomes after palbociclib initiation in HR+/HER2- breast cancer patients across multiple lines. Materials & methods: Adult patients (n=559) were identified in a population-based study between January 2018 and June 2020. Results: Median follow-up time was 41.2months. The starting dose was 125mg for more than 85% of patients, and a third had dose reduction. Median time on treatment was 30.5months for palbociclib + aromatase inhibitors for patients that receivedfirst-line treatment after metastatic diagnosis, and 12.6months for palbociclib + fulvestrant across multiple lines, andlonger for patients that had adose reduction during treatment. At 48months, 59.3 and 27.3% of patients were still alive, respectively. Subsequent lines resulted in median time on treatment of 4.4-7.7months in both groups. Conclusion: Time on treatment for palbociclib was comparable to data from clinical trials, and follow-up allowed us to examine subsequent treatment after initial treatment failure. Dose reduction was common in the real-world setting and did not adversely affect efficacy.

Machine learning survival models trained on clinical data to identify high risk patients with hormone responsive HER2 negative breast cancer

For endocrine-positive Her2 negative breast cancer patients at an early stage, the benefit of adding chemotherapy to adjuvant endocrine therapy is not still confirmed. Several genomic tests are available on the market but are very expensive. Therefore, there is the urgent need to explore novel reliable and less expensive prognostic tools in this setting. In this paper, we shown a machine learning survival model to estimate Invasive Disease-Free Events trained on clinical and histological data commonly collected in clinical practice. We collected clinical and cytohistological outcomes of 145 patients referred to Istituto Tumori “Giovanni Paolo II”. Three machine learning survival models are compared with the Cox proportional hazards regression according to time-dependent performance metrics evaluated in cross-validation. The c-index at 10 years obtained by random survival forest, gradient boosting, and component-wise gradient boosting is stabled with or without feature selection at approximately 0.68 in average respect to 0.57 obtained to Cox model. Moreover, machine learning survival models have accurately discriminated low- and high-risk patients, and so a large group which can be spared additional chemotherapy to hormone therapy. The preliminary results obtained by including only clinical determinants are encouraging. The integrated use of data already collected in clinical practice for routine diagnostic investigations, if properly analyzed, can reduce time and costs of the genomic tests.

Targeting of microRNA-22 Suppresses Tumor Spread in a Mouse Model of Triple-Negative Breast Cancer.

microRNA-22 (miR-22) is an oncogenic miRNA whose up-regulation promotes epithelial-mesenchymal transition (EMT), tumor invasion, and metastasis in hormone-responsive breast cancer. Here we show that miR-22 plays a key role in triple negative breast cancer (TNBC) by promoting EMT and aggressiveness in 2D and 3D cell models and a mouse xenograft model of human TNBC, respectively. Furthermore, we report that miR-22 inhibition using an LNA-modified antimiR-22 compound is effective in reducing EMT both in vitro and in vivo. Importantly, pharmacologic inhibition of miR-22 suppressed metastatic spread and markedly prolonged survival in mouse xenograft models of metastatic TNBC highlighting the potential of miR-22 silencing as a new therapeutic strategy for the treatment of TNBC.

Abstract GS4-09: Pregnancy Outcome and Safety of Interrupting Therapy for women with endocrine responsIVE breast cancer: Primary Results from the POSITIVE Trial (IBCSG 48-14/BIG 8-13)

Abstract Background: Pregnancy after breast cancer (BC) is of substantial importance for many young women at diagnosis and during follow-up. BC treatment including standard endocrine therapy (ET) (5-10 years) may reduce ovarian reserve and the chances of subsequent successful pregnancy, given conception is contraindicated during ET. A temporary interruption of ET to attempt and carry a pregnancy in this population has never been prospectively studied. Methods: POSITIVE is a single-arm, prospective, investigator-initiated, international trial evaluating the safety and pregnancy outcomes of interrupting ET for young women with early-stage hormone-receptor-positive (HR+) BC who desire pregnancy. The primary objective is to assess the risk of BC relapse associated with ET interruption for ~2 years to achieve pregnancy. Women ≤42 years with stage I-III HR+ BC who received adjuvant ET (SERM alone, GnRH analogue plus SERM or AI) for 18 to 30 months and wished to interrupt ET to attempt pregnancy were eligible. The primary endpoint is breast cancer free interval (BCFI) defined as the time from enrollment to the first BC event (local, regional, distant recurrence or a new invasive contralateral BC). Planned sample size was 500 patients. Three interim analyses of BCFI were reviewed by the Data Safety Monitoring Committee (DSMC) to assure a 95% chance of stopping the trial early if the annual BCFI event rate exceeded 4%; with primary analysis triggered after 1600 patient years of follow-up (pyfu) and no more than 46 BCFI events defined as the safety threshold. The DSMC recommended continuing the study following each interim analysis. We now report the primary results. Results: From 12/2014 to 12/2019, 518 women were enrolled. At enrollment, the median age of participants was 37 years (27-43 years); 75.0% were nulliparous, 93.4% had stage I/II disease, 66.3% node-negative. Median time from BC diagnosis to enrollment was 29 months (IQR: 25-32). Tamoxifen alone was the most prescribed ET (41.7%), followed by tamoxifen+ovarian function suppression (35.7%). 62.0% of participants had received neo/adjuvant chemotherapy. At a median follow-up of 41 months (1638 pyfu), 44 participants had experienced a BCFI event, not exceeding the pre-specified safety threshold of 46 events. The 3-year BCFI failure percent was 8.9% (95% CI: 6.3 to 11.6%), similar to the 9.2% (95% CI: 7.6 to 10.8%) calculated in the comparative external control cohort from the SOFT/TEXT trials (Sun et al, Breast 2020). Of 497 women followed for pregnancy status, 368 (74.0%) had at least one pregnancy, 317 (63.8%) had at least one live birth, with a total of 365 babies born. Based on competing risk analysis, 76.3% of patients resumed ET (half within 26 months), 8.3% had BCFI event/death before ET resumption, and 15.4% had not resumed ET yet. Conclusions: The POSITIVE trial demonstrates that for young women with early HR+ BC desiring pregnancy, temporary interruption of ET to attempt pregnancy does not confer a greater short-term risk of recurrence than that observed in a modern historical control group that did not interrupt ET. Most participants have had a live birth. Further follow-up is planned to confirm long-term safety. These results should be considered in counselling BC patients desiring future pregnancy. Citation Format: Ann Partridge, Olivia Pagani, Samuel M. Niman, Monica Ruggeri, Fedro Alessandro A. Peccatori, Hatem A. Azim, Marco Colleoni, Cristina Saura, Chikako Shimizu, Anna Saetersdal, Judith Kroep, Audrey Mailliez, Ellen Warner, Virginia F. Borges, Frédéric Amant, Andrea Gombos, Akemi Kataoka, Christine Rousset-Jablonski, Simona Borstnar, Junko Takei, Jeong Eon Lee, Janice Walshe, Manuel Ruiz Borrego, Halle Moore, Christobel Saunders, Vesna Bjelic-Radisic, Snezana Susnjar, Fatima Cardoso, Karen L. Smith, Teresa Ferreiro Vilarino, Karin Ribi, Kathryn Ruddy, Sarra El-Abed, Martine Piccart, Larissa A. Korde, Aron Goldhirsch, Richard D. Gelber. Pregnancy Outcome and Safety of Interrupting Therapy for women with endocrine responsIVE breast cancer: Primary Results from the POSITIVE Trial (IBCSG 48-14/BIG 8-13) [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 GS4-09.