Hormone-dependent Breast Cancer Research Articles

A functional survey of the regulatory landscape of estrogen-receptor-positive breast cancer evolution.

Only a handful of somatic alterations have been linked to endocrine therapy resistance in hormone-dependent breast cancer (HDBC), potentially explaining ~40% of relapses. If other mechanisms underlie the evolution of HDBC under adjuvant therapy is currently unknown. In this work, we employ functional genomics to dissect the contribution of cis-regulatory elements (CREs) to cancer evolution by focusing on 12 megabases of non-coding DNA, including clonal enhancers, gene promoters, and boundaries of topologically associating domains. Parallel epigenetic perturbation (CRISPRi) in vitro reveals context-dependent roles for many of these CREs, with a specific impact on dormancy entrance and endocrine therapy resistance. Profiling of CRE somatic alterations in a unique, longitudinal cohort of patients treated with endocrine therapies identifies a limited set of non-coding changes potentially involved in therapy resistance. Overall, our data uncover how endocrine therapies triggers the emergence of transient features which could ultimately be exploited to hinder the adaptive process.

Breast Cancer Prevention by Dietary Polyphenols: Microemulsion Formulation and In Vitro Studies

Concerns surrounding breast cancer have been increasing, as it leads to the current global cancer incidence and causes a high mortality rate in women. This study investigated the physiological effects of common dietary polyphenols that might prevent breast cancer progression. Quercetin, kaempferol, and rosmarinic acid were selected to explore their potential bioactivities. Each polyphenol was formulated into a microemulsion to improve its bioactivity and bioavailability. In vitro antioxidant and cytotoxicity activities of the selected polyphenols and their microemulsion forms were further investigated. The optimized microemulsion carrier with 1% oleic acid, 3% ethanol, 10% polysorbate 20, and 86% ultrapure water achieved more than 90% polyphenol encapsulation efficiency. The microemulsion was stable for more than 30 days when encapsulating polyphenol in the fluctuating temperature treatment. In vitro studies suggested that rosmarinic acid-loaded microemulsion had the best antioxidant activity compared with other polyphenol-loaded microemulsions (PL-MEs). Blank microemulsion and all PL-MEs significantly inhibited the proliferation of both hormone-dependent (T47D) and hormone-independent (MDA-MB-231) breast cancer cells. More studies are warranted to confirm the contribution of the microemulsion carrier components to the polyphenols’ improved antioxidant activity and high toxicity of PL-MEs on breast cancer cells.

Regulation of Med1 protein by overexpression of BAP1 in breast cancer cells

ABSTRACT Med1 binds to a nuclear receptor and regulates transcription. Elevated Med1 protein expression promotes cancer growth in hormone-dependent breast and prostate cancers. Med1 protein expression was investigated by deubiquitinating enzymes (DUBs) overexpression in breast cancer cell lines. Various DNA constructs of SRT-DUBs were overexpressed in the MCF7 cell line, and Med1 protein expression was investigated by western blotting. The cell growth and in vitro invasion assay were performed in BRCA1-associated protein 1 (BAP1) wild type and mutant (C91A) overexpressed cells. Ubiquitination of the Med1 protein was observed, and Med1 protein expression and transcriptional activity were verified by various DUBs overexpressed. Although Med1 protein expression increased upon the overexpression of BAP1, it was not affected by the overexpression of BAP1 mutant (C91A). BAP1 was increased by the E2 treatment, which has an important effect on the breast cancer growth, and cell growth was decreased by BAP1 C91A overexpression. However, metastatic capacities were decreased by BAP1. In addition, the binding between the Med1 and the BAP1 protein was observed. These data suggested that BAP1 regulated Med1 protein expression in breast cancer cells and involved in cancer cell growth and metastasis by binding to Med1 protein.

Methylation of the chromatin modifier KMT2D by SMYD2 contributes to therapeutic response in hormone-dependent breast cancer

Activating mutations in PIK3CA are frequently found in estrogen-receptor-positive (ER+) breast cancer, and the combination of the phosphatidylinositol 3-kinase (PI3K) inhibitor alpelisib with anti-ER inhibitors is approved for therapy. We have previously demonstrated that the PI3K pathway regulates ER activity through phosphorylation of the chromatin modifier KMT2D. Here, we discovered a methylation site on KMT2D, at K1330 directly adjacent to S1331, catalyzed by the lysine methyltransferase SMYD2. SMYD2 loss attenuates alpelisib-induced KMT2D chromatin binding and alpelisib-mediated changes in gene expression, including ER-dependent transcription. Knockdown or pharmacological inhibition of SMYD2 sensitizes breast cancer cells, patient-derived organoids, and tumors to PI3K/AKT inhibition and endocrine therapy in part through KMT2D K1330 methylation. Together, our findings uncover a regulatory crosstalk between post-translational modifications that fine-tunes KMT2D function at the chromatin. This provides a rationale for the use of SMYD2 inhibitors in combination with PI3Kα/AKT inhibitors in the treatment of ER+/PIK3CA mutant breast cancer.

Tuning of the Anti-Breast Cancer Activity of Betulinic Acid via Its Conversion to Ionic Liquids.

Betulinic acid (BA) is a natural pentacyclic triterpene with diverse biological activities. However, its low water solubility limits its pharmaceutical application. The conversion of pharmaceutically active molecules into ionic liquids (ILs) is a promising strategy to improve their physicochemical properties, stability, and/or potency. Here, we report the synthesis and characterization of 15 novel ILs containing a cation ethyl ester of a polar, non-polar, or charged amino acid [AAOEt] and an anion BA. Except for [ValOEt][BA], we observed preserved or up to 2-fold enhanced cytotoxicity toward hormone-dependent breast cancer cells MCF-7. The estimated IC50 (72 h) values within the series varied between 4.8 and 25.7 µM. We found that the most cytotoxic IL, [LysOEt][BA]2, reduced clonogenic efficiency to 20% compared to that of BA. In addition, we evaluated the effect of a 72 h treatment with BA or [LysOEt][BA]2, the most cytotoxic compound, on the thermodynamic behavior of MCF-7 cells. Based on our data, we suggest that the charged amino acid lysine included in the novel ILs provokes cytotoxicity by a mechanism involving alteration in membrane lipid organization, which could be accompanied by modulation of the visco-elastic properties of the cytoplasm.

Abstract 3276: The effects of extracellular ATP signaling on the anticancer activities of macrophages

Abstract Among cancers in women worldwide, breast cancer has the highest incidence and the highest mortality. Patients with triple negative breast cancer (TNBC) have a markedly worse outcome in comparison to patients diagnosed with hormone-dependent and human epidermal growth factor receptor-positive breast cancers due to the aggressive and rapidly progressive nature of the disease and the deficit in specifically targeted therapies available. Therefore, there is a need for new therapeutic approaches. Extracellular ATP has been shown to cause cell death in an autocrine and paracrine manner and is also a known danger signal that causes immune activation. Our published data reveals that at high micromolar concentrations extracellular ATP (eATP) can induce cell death through the eATP-gated ion channels, purinergic P2RX7 and P2RX4 receptors. We also showed that in the context of chemotherapy treatment, eATP modulates TNBC cell death at submicromolar concentrations. A feature of the tumor microenvironment is a pronounced increase in the concentrations of eATP (micromolar) to levels that are closer to the threshold for cytotoxicity than in normal tissues (nanomolar). In addition, we discovered that chemotherapy induces the release of eATP from TNBC cells, further augmenting its concentration. Despite this, eATP is rapidly degraded to adenosine by extracellular ATPases (eATPases). It should be noted that extracellular ATP release and activation of its receptor, P2XR7, are prerequisites for the activation of a complex of proteins known as the NLRP3 inflammasome that is critical for IL-1β and IL-18 secretion and the induction of a highly inflammatory form of programmed cell death known as pyroptosis. The objective of this study was to evaluate if augmenting eATP levels using extracellular ATPase inhibitors will increase the efficacy of chemotherapy against THP-1 and differentiated THP-1 cells to undergo an inflammatory form of cell death known as pyroptosis. We treated THP-1 and differentiated THP-1 cells with increasing concentrations of the chemotherapeutic agent paclitaxel in the presence of eATPase inhibitors POM-1 and PSB 069 with eATP content and cell viability being assessed. Additionally, we examined NLRP3 inflammasome activation by immunoblot analysis. We analyzed the oligomerization of NLRP3 and ASC, the cleavage of caspase 1 and gasdermin and the secretion of IL-1β and IL-18, all components of pyroptosis. These results reveal that eATP modulates the chemotherapeutic response in the monocytic THP-1 and differentiated THP-1 cells, which could be exploited to augment the anticancer effects of macrophages on TNBC cells. These preclinical experiments could be applied to develop effective therapies that increase the depth and length of responses to chemotherapy and immunotherapy in TNBCs by augmenting pyroptosis of tumor associate macrophages through enhanced eATP. Citation Format: Jasmine M. Manouchehri, Lynn M. Marcho, Mathew A. Cherian. The effects of extracellular ATP signaling on the anticancer activities of macrophages [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 3276.

Abstract 2977: Novel HSP90 inhibitors with senolytic activity for a targeted therapy in a hormone-induced breast cancer senescence model

Abstract Background: The research into senescent cells, particularly their accumulation and contribution to aging and age-related diseases, has gained significant momentum in recent years. This interest is primarily driven by findings in mouse models, where the excessive buildup of senescent cells is linked to various age-related pathologies. Consequently, there has been a concerted effort in the scientific community to identify and develop senolytics. A notable development in this field is the identification of senolytics within the class of HSP90 inhibitors. These inhibitors, initially investigated for their potential in cancer therapy, have been repurposed due to their high selectivity for senescent cells. Our research has led to new compounds with mild inhibitory activity against HSP90α in response to these challenges. These compounds stand out for their lack of toxic side effects and their demonstrated senolytic activity across multiple cellular models. Objective: The primary objective of this research is to identify and characterize innovative HSP90 inhibitors that exhibit senolytic properties, specifically in the context of hormone-driven cancers. Methods and Results: Utilizing a structure-based virtual screening technique, we identified several compounds displaying strong affinity and predicted inhibitory activity against the target protein, HSP90α. Among these, two inhibitors designated K4 and K5, demonstrated notable senolytic activity in vitro without inducing cytotoxic effects in non-senescent cells. These compounds were tested for their efficacy in senolytic activity and displayed half-maximal inhibitory concentrations (IC50) of 155 nM and 111 nM, respectively. The experimental model for this study was the MCF7 cell line, which was treated with 4-Hydroxytamoxifen (Tam, 10uM for 96 hours) to induce a state of senescence. Subsequent growth curve analyses and beta-galactosidase assays established that Tam treatment effectively halted cell proliferation and induced a senescence state in about 40% of the cell population compared to the ethanol control. When treated with K4 and K5 (10 uM for an additional 96 hours), a significant reduction in the senescent cell population was observed, with K5 showing a particularly pronounced increase in the mortality rate of these cells (up to 2.5-fold compared to the DMSO control). Western blot analysis supported these results, suggesting the effectiveness of K5 combined with Tam in inhibiting proliferation and inducing cell death in MCF7 cells. Conclusion: Our findings propose a novel therapeutic approach for hormone-dependent breast cancer, combining the dual roles of tamoxifen and HSP90 inhibitors to target senescent cancer cells. This strategy could reduce tumor recurrence and contribute to the advancement of cancer treatment methods. Citation Format: Luca Cis, Michela Gottardi Zamperla, Veronica Barbi, Pietro Cigala Fulgosi, Sara De Martino, Aurora Aiello, Simona Nanni, Chiara Cencioni, Davide Pirolli, Paola Tabarelli De Fatis, Giovanni Battista Ivaldi, Marco Malavolta, Christian Steinkühler, Maria Cristina De Rosa, Antonella Farsetti, Sandra Atlante, Carlo Gaetano. Novel HSP90 inhibitors with senolytic activity for a targeted therapy in a hormone-induced breast cancer senescence model [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 2977.

Evaluating flavonoids as potential aromatase inhibitors for breast cancer treatment: In vitro studies and in silico predictions

Aromatase inhibitors are commonly employed in the treatment of hormone-dependent breast cancers, and flavonoids have emerged as a promising alternative to existing drug classes with unfavorable side effects. In this study, we conducted in vitro investigations into CYP19A1 (aromatase) inhibitory potential of 14 flavonoids, including pinocembrin, sakuranetin, eriodictyol, liquiritigenin, naringenin, hesperetin, flavanone, baicalein, chrysin, nobiletin, luteolin, sinensetin, tricin, and primuletin. Flavonoids displaying inhibitory activity were further assessed using in silico tools, such as molecular docking to predict binding affinities, as well as SwissADME, admetSAR, and QED (Quantitative Estimate of Drug-likeness) for drug-likeness prediction. Flavonoids with IC50 values less than 10 μM, pinocembrin, eriodictyol, naringenin, liquirtigenin, sakuranetin, and chrysin, exhibited favorable physicochemical properties and ADME profiles, suggesting their potential for development as novel flavonoid-based aromatase inhibitors. This study would provide valuable insights for the development of flavonoid-based aromatase inhibitors for the treatment of breast cancer.

Novel quinazolines bearing 1,3,4-thiadiazole-aryl urea derivative as anticancer agents: design, synthesis, molecular docking, DFT and bioactivity evaluations

A novel series of 1-(5-((6-nitroquinazoline-4-yl)thio)-1,3,4-thiadiazol-2-yl)-3-phenylurea derivatives 8 were designed and synthesized to evaluate their cytotoxic potencies. The structures of these obtained compounds were thoroughly characterized by IR, 1H, and 13C NMR, MASS spectroscopy and elemental analysis methods. Additionally, their in vitro anticancer activities were investigated using the MTT assay against A549 (human lung cancer), MDA-MB231 (human triple-negative breast cancer), and MCF7 (human hormone-dependent breast cancer). Etoposide was used as a reference marketed drug for comparison. Among the compounds tested, compounds 8b and 8c demonstrated acceptable antiproliferative activity, particularly against MCF7 cells. Considering the potential VEGFR-2 inhibitor potency of these compounds, a molecular docking study was performed for the most potent compound, 8c, to determine its probable interactions. Furthermore, computational investigations, including molecular dynamics, frontier molecular orbital analysis, Fukui reactivity descriptor, electrostatic potential surface, and in silico ADME evaluation for all compounds were performed to illustrate the structure–activity relationship (SAR).

Potential therapeutic efficacy of photodynamic therapy on female hormonal-dependent cancers in a hormonal simulated microenvironment

BackgroundPhotodynamic Therapy (PDT) is a clinically approved cancer treatment. Sex hormones, the key drivers for the development of female hormonal dependent cancers, might affect cancer treatment. There are seldom studies to evaluate the effect of sex hormones mimicked the menstrual cycle on the PDT mediated by prodrug 5-aminolevulinic acid (ALA) and its ester derivatives to the hormonal dependent cancers. AimsTo evaluate the efficacy of sex hormones on Hexyl-ALA-PDT in hormonal dependent cancers and the effect of the sex hormones on heme biosynthetic pathway. MethodsCell culture system that mimicked the fluctuation of sex hormones 17β-estradiol (E2) and progesterone (PG) in the menstrual cycle was developed. Two pairs of hormonal-independent and hormonal dependent uterine sarcoma and breast cancer cell lines were used as cell models. Hexyl-ALA induced PpIX production and intracellular localization were examined. Key enzymes for PpIX synthesis were analysed. Hexyl-ALA-PDT mediated phototoxicity was evaluated. ResultsThe PpIX generation was increased in the hormonal-dependent cells (28–50 %) when cultured in the hormonal microenvironment with long incubation of Hexyl-ALA for 15 and 24 h compared to that cultured without hormones; whereas only slight difference in PpIX generation in their hormonal-independent counterpart. The PpIX generation was in a time-dependent manner. The CPOX, PPOX and FECH expressions were significantly enhanced by Hexyl-ALA-PDT in uterine sarcoma cells in hormonal microenvironment. Hexyl-ALA-PDT triggered significant increase of PPOX expression in breast cancer cells in hormonal microenvironment. The Hexyl-ALA-PDT phototoxicity was enhanced by 18–40 % in cells cultured in the hormonal system in a dose-dependent manner. ConclusionThe PpIX generation and the efficacy of Hexyl-ALA-PDT in both uterine sarcoma and breast cancer cells was significantly enhanced by the sex hormones via cultured in the hormonal microenvironment.

Abstract A062: Somatic engineering of rat models to recapitulate human breast cancer evolution and heterogeneity

Abstract Estrogen receptor (ER) positive breast cancer accounts for over 75% of all presenting clinical cases. In addition, almost all Ductal Carcinoma in situ (DCIS) lesions, now accounting for about 25% of all newly diagnosed ‘breast cancers’, are ER-dependent. Despite the high occurrence, the molecular underpinnings regulating DCIS initiation and progression to invasive disease remain elusive. This gap in knowledge is primarily due to the dearth of suitable preclinical models that accurately emulate breast cancer heterogeneity. To overcome this impediment, we developed a platform of somatic models by engineering the rat mammary gland and manipulating the genes most frequently mutated in hormone-dependent (pre-)breast cancer. This has successfully led to the generation of ER-positive disease models that provide a nuanced understanding of ER functionality and the complex mechanisms of ER signaling, which we show to be dependent on the cancer genotype. This has potential implications for the formulation of innovative endocrine therapy treatment regimens. Our models have generated an array of tumor types, including ductal and lobular carcinomas, manifesting both in situ and invasive phenotypes, faithfully recapitulating human breast disease and the evolution of tumorigenesis. Intriguingly, our results indicate how different oncogenic mutations modulate not only the architectural and histopathological characteristics of cancer but also the immune microenvironment, thereby generating possibilities for future therapeutic testing. Our research augments the range of available ER-positive in situ and invasive breast cancer models, benefitting the stratification of indolent from aggressive disease and facilitating the exploration of novel treatment strategies for this pervasive breast cancer subtype. Citation Format: Catrin Lutz, Ji-Ying Song, Hendrik A Messal, Madelon Badoux, Timo Eijkman, Bim de Klein, Jelle Wesseling, Jos Jonkers. Somatic engineering of rat models to recapitulate human breast cancer evolution and heterogeneity [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 A062.

Loading of anticancer drug anastrozole using Fe3O4@SiO2

Anastrozole is a prescription drug that is used to treat hormone-dependent breast cancer, mostly in women who have gone through menopause. Once a day, it is taken by mouth. Anastrozole stops the activity of an enzyme called aromatase, which changes androgens into oestrogens. But taking the drug often comes with side effects that depend on how much you take, such as tiredness, diarrhea, hot flashes, nausea, headaches, muscle and joint pain, and so on. Anastrozole has also been linked to other side effects and more bone loss. To overcome the side effects of anastrozole and for their efficient delivery anastrozole must be loaded on the surfaces which is biocompatible and stable towards human body. So, the co-precipitation method was used to make iron oxide nanoparticles, which were then covered with silica using the Stober method. The made Fe3O4@SiO2 nanocomposite was taken out as a black powder and studied using FTIR, EDX, and SEM. The SEM picture showed that the Fe3O4 and Fe3O4@SiO2 nanoparticles size ranges were between 30 and 45 nm and 55 to 70 nm respectively. We also looked at how contact time, pH, and the amount of nanocomposite affected the loading of the drug. The best adsorption (85.6%) happened when the reaction lasted 12 h, the pH was 4, and the adsorbent dose was 10 mg.

Computational studies and structural insights for discovery of potential natural aromatase modulators for hormone-dependent breast cancer

Introduction: The aromatase enzyme plays an important role in the progress of hormone-dependent breast cancer, especially in estrogen receptor-positive (ER+) breast cancers. In case of postmenopausal women, the aromatization of androstenedione to estrone in adipose tissue is the most important source of estrogen. Generally 60%-75% of pre- and post-menopausal women suffer from estrogen-dependent breast cancer, and thus suppressing estrogen has been recognized to be a successful therapy. Hence, to limit the stimulation of estrogen, aromatase inhibitors (AIs) are used in the second-line treatment of breast cancer. Methods: The present computational study employed an in silico approach in the identification of natural actives targeting the aromatase enzyme from a structurally diverse set of natural products. Molecular docking, QSAR studies and pharmacophore modeling were carried out using the VLife Molecular Design Suite (version 4.6). The stability of the compounds was confirmed by molecular dynamics. Results: From molecular docking and analysis of interactions with the amino acid residues of the binding cavity, it was found that the amino acid residues interacting with the non-steroidal inhibitors exhibited π-stacking interactions with PHE134, PHE 221, and TRP 224, while the steroidal drug exemestane lacked π-stacking interactions. QSAR studies were performed using the flavonoid compounds, in order to identify the structural functionalities needed to improve the anti-breast cancer activity. Molecular dynamics of the screened hits confirmed the stability of compounds with the target in the binding cavity. Moreover, pharmacophore modelling presented the pharmacophoric features of the selected scaffolds for aromatase inhibitory activity. Conclusion: The results presented 23 hit compounds that can be developed as anti-breast cancer modulating agents in the near future. Additionally, anthraquinone compounds with minor structural modification can also serve to be potential aromatase inhibitors. The in silico protocol utilised can be useful in the drug discovery process for development of new leads from structurally diverse set of natural products that are comparable to the drugs used clinically in breast cancer therapy.

Aromatase inhibition using Juniperus procera phytochemical constituents: molecular docking study

AbstractThe key step in the biosynthesis of estrogen is the enzyme activity of aromatase. Several malignancies, including breast cancer, have been linked to the initiation and progression of estrogen overexpression. Exemestane, Arimidex and Femara are the most common aromatase inhibitors used to treat hormone-dependent breast cancers. Drug resistance and side effects are commonly associated with these treatments. The purpose of this in silico study was to list the chemical compounds of Juniperus procera that have been published in scientific papers. The second goal was to evaluate the inhibitory activity of 124 phytochemicals of Juniperus procera compared to known aromatase inhibitors such as Exemestane, Arimidex and Femara. The 3D structure of aromatase (PDB id: 3s7s) employed for docking studies using AutoDock Tools as well as normal mode analysis studies utilizing the NMSim web server. Juniperolide, Kaurenoic acid and Isocupressic acid were identified as competitive aromatase inhibitors compared to FDA approved anti-cancer drugs, specifically Exemestane, Arimidex and Femara. The stability of the ligand–protein interface was studied to support the docking findings. To our knowledge, this is the first study that investigates the possible inhibition roles of some compounds of Juniperus procera on the aromatase enzyme.

Opportunities and prospects for the treatment of hormone-dependent breast cancer

The high incidence of breast cancer requires increased attention to the problem of rational pharmacotherapy of this condition. When choosing tactics for the treatment of breast cancer, it is recommended to take into account the immunohistochemical subtype of cancer cells. In the case of detection of estrogen-positive expression, an obligatory component of pharmacotherapy is endocrine therapy with antiestrogen orientation. Despite the fact that there are already many years of positive experience with the use of selective estrogen receptor modulators and aromatase inhibitors, the search for new more effective agents continues in terms of prolonging the life of patients and reducing the risk of adverse reactions.
 In recent years, cyclin-dependent kinase 4/6 inhibitors have been added to first-line therapy, which is a breakthrough in the treatment of metastatic breast cancer. The introduction of combined antiestrogen therapy with targeted agents that have the ability to inhibit phosphatidylinositol-3-kinase is logical in the event of resistance to primary endocrine therapy. However, the need to search and study new drugs remains. In this regard, the most promising direction is the development of agents that can reduce the expression of the Estrogen receptor alpha protein, and block estrogen-dependent and independent estrogen receptor signaling.

Towards a New Generation of Hormone Therapies: Design, Synthesis and Biological Evaluation of Novel 1,2,3-Triazoles as Estrogen-Positive Breast Cancer Therapeutics and Non-Steroidal Aromatase Inhibitors.

Aromatase inhibitors (AIs) show promising features as drugs to treat estrogen-responsive breast cancer as they block aromatase activity, the key enzyme in estrogen synthesis. The current AIs approved by the Food and Drug Administration for breast cancer treatment present severe adverse effects. For these reasons, it is important to develop of new AIs that are more specific and sensitive. In this paper, we report the synthesis and the characterization of new nonsteroidal aromatase AIs containing triazoles moieties for the treatment of hormone-dependent breast cancer in post-menopausal women. A new series of 1,2,3-triazole based molecules were successfully synthetized and their chemical structures were determined from the spectral data (FT-IR, 13C NMR, 1H NMR, mass spectroscopy) and micro-analytical data. Additionally, the physical properties of the newly synthesized derivatives were reported. The novel compounds were also tested for their anticancer activity in both breast cancer (MCF7 and T-47D) and normal breast (MCF 10A) cell lines, evaluating their effect on cell proliferation, migration, and invasion. The results revealed that the compounds exhibited promising and specific anti-cancer action.

Therapeutic implications of the interplay between interferons and ER in breast cancer

The involvement of interferons (IFNs) in various diseases, including breast cancer, has sparked controversy due to their diverse roles in immunity and significant impact on pathological mechanisms. In the context of breast cancer, the heightened expression of endogenous IFNs has been linked to anti-tumor activity and a favorable prognosis for patients. Within the tumor tissue and microenvironment, IFNs initiate a cascade of molecular events involving numerous factors, which can lead to either cooperative or repressive interactions. The specific functions of IFNs in breast cancer vary depending on the two major disease phenotypes: hormone dependent (or responsive) and hormone independent (or unresponsive) breast cancer. Hormone dependence is determined by the presence of estrogen receptors (ERs). The interplay between the IFN and ER signaling pathways, and the involvement of intermediate factors such as NFκB, are areas that have been somewhat under-researched, but that hold potential importance for the understanding and treatment of breast cancer. This review aims to provide a comprehensive overview of the actions of IFNs in breast cancer, particularly in relation to the different breast cancer phenotypes and the significance of comprehending the underlying mechanisms. Furthermore, the use of IFN-based therapies in cancer treatment remains a topic of debate and has not yet gained widespread acceptance. However, emerging discoveries may redirect focus towards the potential of IFN-based therapies.

Synthesis and biological activities of flavonoid sulfamates as steroid sulfatase inhibitors

Synthesis of potent flavonoid sulfamate inhibitors of the enzyme steroid sulfatase (STS), a topical target in treating postmenopausal women with hormone-dependent breast cancer, is described in the current article. Novel compounds were examined for estrone sulfatase (E1-STS) inhibition in intact MCF-7 breast cells. The strategies adopted to develop STS inhibitors which, while active in vivo, are devoid of any estrogenicity that would limit their use for breast cancer therapy (e.g. estrone 3-O-sulfamate, EMATE), were broadly successful. Several molecules of flavonoid sulfamates were synthesized that potentially possess both aromatase and steroid sulfatase inhibitory properties. The isoflavane-4',7-O,O-bis-sulfamate (equol bis-sulfamate) and flavone-6,4'-O,O-bis-sulfamate were found to be the most potent inhibitors of all the flavonoid sulfamate analogs in vitro, inhibiting STS by about 99% at 0.1μM in MCF-7 cells. Some of these flavonoid sulfamates were also found to be active against both enzymes’ STS and aromatase (e.g., 5-hydroxy-7-methoxyflavone-4'-O-sulfamate, 5-hydroxy-flavone-4',7-O,O-bis-sulfamate, and 5,7-dihydroxy flavanone-4'-O-sulfamate), thus demonstrating the novel concept of a dual inhibitor. The availability of flavonoid sulfamates as STS inhibitors may enable to use of them as a therapy in the treatment of breast cancer.

Phenomenon of suppression of estrogen signaling in breast cancer cells under ultraviolet irradiation: role of Snail proteins

Introduction. The study of the effect of irradiation or any other DNA-damaging agents on the sensitivity of tumors to conservative therapy, drug or hormonal, is among the most imporant tasks that determine the efficiency of combined therapy of cancer patients.Aim. To investigate the effect of irradiation on the activity of key signaling proteins and the level of hormone dependence of breast cancer cells.Materials and methods. The experiments were performed on in vitro cultured estrogen-dependent MCF-7 breast cancer cells. Ultraviolet (UV) irradiation in the range of 254 nm with the intensity of 25–50 J/m2 was used as an experimental model to study the response of tumor cells to DNA damage. Cell growth rate was determined using the MTT test, cell survival after irradiation was analyzed using the colony-forming test. Estrogen receptor transcriptional activity was determined by reporter assay; cellular protein expression was determined by immunoblotting.Results. Single UV irradiation of MCF-7 cells leads to a marked increase in the level of apoptotic markers: p53, cPARP, suppression of expression of growth signaling proteins: CDK4/6 and estrogen receptor α (ERα). The above changes are accompanied with an increase in phosphorylation of Akt protein kinase and a marked increase in the expression of Snail1, one of the key proteins of epithelial-mesenchymal transition. In UV-resistant MCF-7/UVR cell subline obtained under repeated irradiation cycles, the levels of apoptotic and growth signaling proteins (p53, cPARP, CDK4/6) return to control levels, except for the phosphorylated form of Akt and Snail1, whose content remains high. Transfection of Snail1-expressing plasmid into MCF-7 cells is accompanied by activation of apoptotic signaling, suppression of ERα activity, and development of partial hormone resistance; however, the sensitivity of cells to irradiation is practically unchanged. Transfection of microRNA-181a-2, one of the microRNAs associated with cell resistance, simultaneously activates Akt and Snail1 and leads to the development of cross-resistance of cells to irradiation and hormonal drugs.Conclusion. The obtained data allow us to consider irradiation-induced Snail1 activation as one of the factors involved in deregulation of estrogen signaling and formation of cell resistance to hormonal drugs, while simultaneous activation of Akt and Snail1 is accompanied by the development of cross-resistance to irradiation and hormonal drugs.

Identification of non-steroidal aromatase inhibitors via in-silico and in-vitro studies.

Breast cancer is the most common cancer affecting women worldwide, including Pakistan. More than half of breast cancer patients have hormone-dependent breast cancer, which is developed due to the over-production of estrogen (the main hormone in breast cancer). The biosynthesis of estrogen is catalyzed by the aromatase enzyme, which thus serves as a target for the treatment of breast cancer. During the current study, biochemical, computational, and STD-NMR methods were employed to identify new aromatase inhibitors. A series of phenyl-3-butene-2-one derivatives 1-9 were synthesized and evaluated for human placental aromatase inhibitory activity. Among them, four compounds 2, 3, 4, and 8 showed a moderate to weak inhibitory activity (IC50 = 22.6 - 47.9 µM), as compared to standard aromatase inhibitory drugs, letrozole (IC50 = 0.0147 ± 1.45 µM), anastrozole (IC50 = 0.0094 ± 0.91 µM), and exemestane (IC50 = 0.2 ± 0.032 µM). Kinetic studies on two moderate inhibitors, 4 and 8, revealed a competitive- and mixed-type of inhibition, respectively. Docking studies on all active compounds indicated their binding adjacent to the heme group and interaction with Met374, a critical residue of aromatase. STD-NMR further highlighted the interactions of these ligands with the aromatase enzyme. STD-NMR-based epitope mapping indicated close proximity of the alkyl chain followed by an aromatic ring with the receptor (aromatase). These compounds were also found to be non-cytotoxic against human fibroblast cells (BJ cells). Thus, the current study has identified new aromatase inhibitors (compounds 4, and 8) for further pre-clinical and clinical research.