Breast Cancer Drug Research Articles

Revealing Propolis Potential Activity on Inhibiting Estrogen Receptor and Heat Shock Protein 90 Overexpressed in Breast Cancer by Bioinformatics Approaches.

Breast cancer is the most commonly diagnosed cancer globally, with the highest incidence of breast cancer occurring in Asian countries including Indonesia. Among the types of breast cancer, the estrogen receptor (ER)-positive subtype which is prominent with estrogen receptor alpha (ERα) and heat shock protein 90 (HSP90) overexpression genes becomes the most prevalent than the others, approximately 75% of all breast cancer cases. ERα and HSP90 play a role in breast cancer activities including breast tumor growth, invasion, and metastasis mechanism. Propolis, a natural bee product, has been explored for its anticancer activity. However, there is lack of studies that evaluated the potential inhibitor from propolis compounds to the ERα and HSP90 proteins. Therefore, this article focuses on examining the correlation between ERα and HSP90's role in breast cancer and investigating the potential of 93 unique propolis compositions in inhibiting these genes in breast cancer using in silico approaches. This study revealed the positive correlation between ERα and HSP90 genes in breast cancer disease development. Furthermore, we also found novel potential bioactive compounds of propolis against breast cancer through binding with ERα and HSP90; they were 3',4',7-trihydroxyisoflavone and baicalein-7-O-β-D glucopyranoside, respectively. Further research on these compounds is needed to elucidate deeper mechanisms and activity in the real biological system to develop new breast cancer drug treatments.

Pyridine Based Chalcone Derivatives as Inhibitor Against Breast Cancer: A Computational Approach.

To evaluate the potency of two pyridine chalcone derivatives, CHA and CHB, against breast cancer, their inhibitory activities were assessed on four different cancer cell lines (6CZ2, 6CZ3, 6CZ4, and 5TWU) using the docking and scoring method. The binding energies of CHA on the four receptors were found to be -8.0, -8.5, -8.6, and -8.3 kcal/mol, respectively, and for the CHB ligand, they were -7.9, -8.3, -8.0, and 8.1 kcal/mol. A standard breast cancer drug, exemestane, was also docked with these cancer cell lines, yielding binding energies of -8.1, -8.9, 8.9, and -8.4 kcal/mol, respectively. Both ligands demonstrated good conformity with the standard drug, with CHA exhibiting higher binding energy than CHB. Additionally, both compounds adhere strictly to the Rule of Five (Lipinski’s rule), suggesting that these drug-like compounds may be suitable for oral administration.

Quantum DFT analysis and molecular docking investigation of various potential breast cancer drugs.

Breast cancer is among the deadliest cancers worldwide, highlighting the urgent need for effective treatments. This study employs density functional theory (DFT) and molecular docking analyses to evaluate the anti-cancer efficacy and specificity of drug molecules lapatinib, tucatinib, neratinib, anastrozole, and letrozole. DFT analysis provides comprehensive insights into the structural, electronic, optical, and vibrational properties of these drugs, helping to elucidate their molecular stability and reactivity through global reactivity descriptors. Additionally, molecular docking simulations reveal the binding conformations and interaction profiles of these drugs with key breast cancer targets, underscoring their therapeutic potential. Docking results indicate that lapatinib, tucatinib, and neratinib have high binding affinities for HER2, with lapatinib exhibiting the strongest overall binding, particularly with PDK1 (PDB ID: 1UU7), PAK4 (PDB ID: 2X4Z), GSK3 (PDB ID: 1GNG), and HER2 (PDB ID: 2IOK). The stable hydrogen bonding and other interactions observed with lapatinib support its effectiveness in treating HER2-positive breast cancers, tucatinib's selective HER2 binding reduces off-target effects, while neratinib's irreversible binding provides prolonged inhibition, making it useful for overcoming resistance in HER2-positive cases. In contrast, anastrozole and letrozole show lower binding affinities for HER2 and EGFR due to their simpler structures but are potent aromatase inhibitors, making them effective in treating estrogen receptor-positive (ER-positive) breast cancers. In conclusion, DFT and molecular docking studies affirm the suitability of lapatinib, tucatinib, and neratinib for HER2-positive cancers, while anastrozole and letrozole are effective in ER-positive cancers, emphasizing the role of molecular structure and binding affinity in optimizing cancer treatment strategies.

Autophagy Modulation in Therapeutic Strategy of Breast Cancer Drug Resistance.

Breast cancer (BC) is a prevalent malignancy globally. Autophagy plays a pivotal role in all stages of this disease, including development, metastasis, and onset. Therefore, it is envisaged that targeting cell autophagy through appropriate tactics would evolve into a novel breast cancer prevention and therapy strategy. A multitude of chemotherapeutic medications can stimulate autophagy in tumor cells. It has led to divergent opinions on the function of autophagy in cancer treatment, as both stimulating and blocking autophagy can improve the effectiveness of anticancer medications. Consequently, the decision of whether to stimulate or inhibit autophagy during breast cancer treatment has become crucial. Understanding the distinctive mechanisms of autophagy in BC and its significance in medication therapy might facilitate the creation of targeted treatment plans based on the roles particular to autophagy. This review summarizes recent studies on the autophagy mechanism in breast cancer and provides insights into autophagy-based BC therapeutic techniques, giving fresh avenues for future BC treatment.

Advances in Breast Cancer Drug Discovery: A Review of Therapeutic Strategies and Studies Involving Photosensitizers, Caged Xanthones and Thiosemicarbazones Derivatives

Cancer is one of the major causes of death worldwide, and breast cancer is the most prevalent and deadly type among women. Despite the side effects and the phenomena of chemoresistance associated with the drugs involved, chemotherapy remains the main therapeutic strategy to combat and control breast cancer. Therefore, several new classes of compounds against breast cancer have been explored, in an effort to identify new drug candidates with alternative mechanisms of action. The principal results of such exploration, focusing on caged xanthones, thiosemicarbazones and photosensitizers, are presented in this review, along with the main aspects of the drug discovery process against breast cancer. More specifically, the design, structure-activity relationship investigations and anti-breast cancer properties of these three classes are described and discussed in this work.

Etlingera elatior Compounds as Anticancer Agents of Breast Cancer Through Inhibition of Progesterone Receptor: An In Silico Study

Breast cancer is the leading cause of cancer-related death in women globally. Progesterone receptor (PR) is known as the prime example of receptors amenable to targeted breast cancer drug therapy. Etlingera elatior is an herbal plant that has been renowned to have anticancer effect. This study aimed to identify the potential compounds derived from Etlingera elatior as anticancer agents of PR in breast cancer using molecular docking method. This study used fifteen compounds from Etlingera elatior along with lonaprisan as the comparative drug. The PR was downloaded from RCSB, whereas compounds and lonaprisan were from Pubchem. The drug-likeness test based on Lipinski’s rule of five was conducted using SwissADME. Toxicity analysis using admetSAR 2.0 was used to predict toxicological profile of the compounds. Compounds and lonaprisan were docked on PR using AutoDock tools 1.5.6 and AutoDock Vina 1.1.2. Molecular interactions were visualized by Discovery Studio v16. A total of nine compounds met the criteria as drugs based on drug-likeness and toxicity tests. All nine compounds except caffeic acid and vanillic acid had higher binding affinities on PR compared with lonaprisan. Ergosterol peroxide exhibited the highest binding affinity on PR with values of -9.8 kcal/mol. Moreover, ergosterol peroxide-PR interaction had thirteen hydrophobic bonds and a hydrogen bond with amino acid residues were found in the active site of PR. Most of the compounds found in Etlingera elatior have the potential to be anticancer agents of PR in breast cancer with ergosterol peroxide being the most potential compound. Further in vitro and in vivo research are needed.Keywords: breast cancer, ergosterol peroxide, Etlingera elatior, progesterone receptor, in silico.

Repurposing FDA-Approved Anastrozole-based Drugs for Breast Cancer through Drug-Drug Transcriptomic Similarity and Cavity Detection Guided Blind Docking

Breast cancer remains a significant global health concern, necessitating innovative strategies for drug discovery and development. Repurposing existing drugs offers a promising avenue, leveraging the wealth of information available on food and drug administration (FDA) approved compounds. This study investigates the repurposing potential of anastrozole-based drugs, already established for their efficacy in certain conditions, for breast cancer treatment. This research presents a multifaceted investigation into the identification, structural refinement, and virtual screening of potential therapeutics targeting the aromatase CYP19A enzyme, a crucial player in hormone-related conditions such as breast cancer. The study commences with the identification of anastrozole-based drugs exhibiting transcriptomic profiles closely resembling known breast cancer therapeutics. Through a comprehensive analysis, a subset of compounds demonstrates high transcriptomic similarity, suggesting shared molecular pathways and target interactions. Notably, anastrozole, a well-known aromatase inhibitor, emerges as a top candidate, highlighting its potential in breast cancer treatment. The crystallographic structure of aromatase CYP19A is subjected to meticulous preprocessing using the PDB-REDO server, resulting in significant improvements in various validation metrics. Structural changes, including alterations in rotamers, removal of water molecules, and peptide flips, indicate the success of the refinement process in enhancing the accuracy of the protein model. The refined structure serves as a reliable foundation for subsequent studies. Further, structure-based cavity detection unveils potential binding sites on the aromatase enzyme. Docking studies employing the cb-dock server elucidate the interaction patterns and binding affinities of selected compounds within these cavities. Anastrozole, along with other candidates like dolasetron and stiripentol, exhibits promising binding scores and interacts with specific residues crucial for enzyme activity. This integrative approach, combining transcriptomic similarity analysis, structural refinement, and virtual screening, provides valuable insights into potential lead compounds for the inhibition of aromatase in breast cancer therapy. The identified compounds offer a starting point for further experimental validation and drug development. The most promising compound that can be repurposed for as an aromatase inhibitor is dolasetron. Overall, this research contributes to the ongoing efforts to leverage computational methodologies for the rational design of targeted therapeutics against hormone-related disorders.

Guidelines for clinical application of platinum drugs in breast cancer (2023 edition)

Breast cancer is the most common malignant tumor in women around the world, and it is also a common cause of death in female patients with malignant tumors in China, which seriously harms women's health. At present, with the application of comprehensive treatment approaches, breast cancer has become one of the most effective solid tumors. Platinum drugs are widely used in malignant tumors, and they are also commonly used as effective chemotherapeutic drugs for breast cancer. To regulate the application of platinum drugs in breast cancer, the experts from Breast Cancer Group, Branch of Oncologist, Chinese Medical Doctor Association, discuss and approve the "Guidelines for clinical application of platinum drugs in breast cancer (2023 edition)" . This guideline is developed from the "Expert consensus on the clinical application of platinums in advanced breast cancer (2020 version)" , which is updated from the latest evidence based on breast cancer at home and abroad, for platinum drugs in breast cancer clinical use, application scheme, efficacy analysis and treatment of adverse effects. This guideline aims to guide clinicians to use drugs rationally, and to further standardize the diagnosis and treatment.

Mechanism of ferroptosis in breast cancer and research progress of natural compounds regulating ferroptosis.

Breast cancer is the most prevalent cancer worldwide and its incidence increases with age, posing a significant threat to women's health globally. Due to the clinical heterogeneity of breast cancer, the majority of patients develop drug resistance and metastasis following treatment. Ferroptosis, a form of programmed cell death dependent on iron, is characterized by the accumulation of lipid peroxides, elevated levels of iron ions and lipid peroxidation. The underlying mechanisms and signalling pathways associated with ferroptosis are intricate and interconnected, involving various proteins and enzymes such as the cystine/glutamate antiporter, glutathione peroxidase 4, ferroptosis inhibitor 1 and dihydroorotate dehydrogenase. Consequently, emerging research suggests that ferroptosis may offer a novel target for breast cancer treatment; however, the mechanisms of ferroptosis in breast cancer urgently require resolution. Additionally, certain natural compounds have been reported to induce ferroptosis, thereby interfering with breast cancer. Therefore, this review not only discusses the molecular mechanisms of multiple signalling pathways that mediate ferroptosis in breast cancer (including metastasis, invasion and proliferation) but also elaborates on the mechanisms by which natural compounds induce ferroptosis in breast cancer. Furthermore, this review summarizes potential compound types that may serve as ferroptosis inducers in future tumour cells, providing lead compounds for the development of ferroptosis-inducing agents. Last, this review proposes the potential synergy of combining natural compounds with traditional breast cancer drugs in the treatment of breast cancer, thereby suggesting future directions and offering new insights.

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.

Presence of Breast Cancer Information Recorded in United Kingdom Primary Care Databases: Comparison of CPRD Aurum and CPRD GOLD (Companion Paper 1).

To evaluate the presence of data elements related to diagnosis and treatment of malignant breast cancer in CPRD Aurum compared to those in the previously validated CPRD GOLD. Females in CPRD Aurum or GOLD with a first-time code for malignant breast cancer, mastectomy, or ≥1 prescription for tamoxifen or aromatase inhibitors (2004-2019) were selected. We compared the presence of the codes for breast cancer diagnosis, surgeries (mastectomy, lumpectomy), tamoxifen and aromatase inhibitor prescriptions, radiation, chemotherapy, and supporting clinical codes (suspected breast cancer, lump symptoms, biopsy, lumpectomy, cancer care, referral/visit to specialist, palliative care). Age standardized incidence rates of breast cancer diagnosis in CPRD Aurum and GOLD were calculated. There were 131,936 eligible patients in CPRD Aurum and 69,102 patients in GOLD. A similar proportion of patients in CPRD Aurum and GOLD had codes for breast cancer diagnosis, mastectomy, drug prescriptions, lump, biopsy, lumpectomy, chemotherapy, and cancer and palliative care coded in their electronic record during follow-up. However, suspected breast cancer, radiation, and referral/visits to specialists were coded more frequently in patients in CPRD Aurum compared to GOLD. Age-standardized incidence rates were similar for CPRD Aurum and GOLD. Overall, there was consistency between data elements related to malignant breast cancer recorded in CPRD Aurum and GOLD, particularly for the most informative clinical details. These findings provide reassurance that breast cancer information recorded in CPRD Aurum is generally comparable to that recorded in the previously validated CPRD GOLD and support the use of CPRD Aurum for breast cancer research.

Potent VEGFR-2 inhibitors for resistant breast cancer: a comprehensive 3D-QSAR, ADMET, molecular docking and MMPBSA calculation on triazolopyrazine derivatives

More people are being diagnosed with resistant breast cancer, increasing the urgency of developing new effective treatments. Several lines of evidence suggest that blocking the kinase activity of VEGFR-2 reduces angiogenesis and slows tumor growth. In this study, we developed novel VEGFR-2 inhibitors based on the triazolopyrazine template by using comparative molecular field analysis (CoMFA) and molecular similarity indices (CoMSIA) models for 3D-QSAR analysis of 23 triazolopyrazine-based compounds against breast cancer cell lines (MCF -7). Both CoMFA (Q2 = 0.575; R2 = 0.936, Rpred2 = 0.956) and CoMSIA/SE (Q2 = 0.575; R2 = 0.936, Rpred2 = 0.847) results demonstrate the robustness and stability of the constructed model. Six novel compounds with potent inhibitory activity were carefully designed, and screening of ADMET properties revealed their good oral bioavailability and ability to diffuse through various biological barriers. When compared with the most active molecule in the data set and with Foretinib (breast cancer drug), molecular docking revealed that the six designed compounds had strengthened affinity (−8.9 to −10 kcal/mol) to VEGFR-2. Molecular Dynamics Simulations and MMPBSA calculations were applied to the selected compound T01 with the highest predicted inhibitory activity, confirming its stability in the active pocket of VEGFR-2 over 100 ns. The present results provided the basis for the chemical synthesis of new compounds with improved inhibitory properties against the breast cancer cell line (MCF -7).

Tamoxifen induced cardiac damage via the IL-6/p-STAT3/PGC-1α pathway

Tamoxifen (TAM) is an effective anticancer drug for breast and ovarian cancer. However, increased risk of cardiotoxicity is a long-term clinical problem associated with TAM, while the underlying mechanisms remain unclear. Here, we performed experiments in cardiomyocytes and tumor-bearing or nontumor-bearing mice, and demonstrated that TAM induced cardiac injury via the IL-6/p-STAT3/PGC-1α/IL-6 feedback loop, which is responsible for reactive oxygen species (ROS) accumulation. Compared with non-tumor bearing mice, tumor-bearing mice showed stronger cardiac toxicity after TAM injection, although there was no significant difference. In vitro experiments demonstrated STAT3 phosphorylation inhibitor can increase PGC-1α expression and protect cardiomyocyte via decreasing ROS. Since tumor has higher STAT3 phosphorylation and IL-6 expression level, our research results indicated combining TAM and STAT3 inhibitor might be an effective treatment strategy which can provide both tumor killing and cardioprotective function. Further in vivo research is needed to fully elucidate the effect and mechanisms of the combination therapy of TAM and STAT3 inhibitor.

Structure-based design, synthesis and biological evaluation of N-substituted 6H-thiochromeno[2,3–c]quinolin-12(12H)-one as potential breast cancer drugs

Tetraheterocyclic compounds, derived from natural sources and contemporary pharmaceuticals, have shown promise as multitarget therapeutic agents. However, their mechanisms of action remain partially understood. In this study, we synthesized a series of 6H-thiochromeno[2,3-c]quinolin-12(12H)-one derivative, totaling 26 compounds, and assessed their potential for therapeutic application. We evaluated their effects on cell proliferation and conducted NCI-60 cell panel assays. MTT assays revealed that select compounds exhibited notable antiproliferative activity against two breast cancer cell lines (MCF-7 and MDA-MB-468). Notably, compounds 17 and 18 displayed the highest cytotoxicity against these cell lines. Furthermore, one-dose assays of the NCI-60 human tumor cell line screening program identified compounds 6, 7, 16, 18, 20, 24, 25, and 30 for further investigation.Subsequent five-dose cytotoxicity studies focused on compounds 18 and 20, which met the threshold inhibition criteria across a panel of cell lines. Our study highlights the effectiveness of compounds 18 and 20 in targeting breast cancer cell lines. Molecular docking simulations revealed that these compounds bind to the active sites of topoisomerase I (TOPO I). Our findings suggest that these novel compounds are promising anticancer agents, particularly against breast cancer, and are worthy of consideration as lead pharmacological candidates.

42P A promising anticancer drug for triple-negative breast cancer: OZ-001 suppresses tumor growth by dual targeting STAT3 and calcium signaling

42P A promising anticancer drug for triple-negative breast cancer: OZ-001 suppresses tumor growth by dual targeting STAT3 and calcium signaling

Additive Effects of Helix aspersa Mucus Fractions with Chemotherapy Drugs in Breast Cancer: Exploring Anti-proliferative Potential

This study investigated the anti-proliferative effects of biologically active substances (BAS) derived from the mucus of the garden snail Helix aspersa on breast cancer cell lines (MCF-7 and MDA-MB-231) and a non-cancerous cell line (MCF-10A). Two mucus fractions with different molecular weights (Mw) were examined, and their interactions with the chemotherapy drugs cisplatin and tamoxifen were evaluated.
 The results showed that the mucus fractions exhibited a slight anti-proliferative effect on breast cancer cells, with the fraction having Mw above 50 kDa demonstrating stronger activity compared to the fraction with Mw above 20 kDa. Furthermore, the combination of the mucus fractions with cisplatin or tamoxifen resulted in significant reductions in the half effective dose, indicating possible synergistic effects which were more pronounced with the fraction having Mw above 20 kDa. Dose-response curves and microscopic images supported the presence of such effects, revealing lower IC50 values and significant cell death when the cancer cells were treated with the combination of the mucus fractions and chemotherapy drugs. However, the analysis using the (highest single agent) HSA model indicated mostly additive interactions between the mucus fractions and chemotherapy drugs.
 These findings suggest the potential of biologically active substances derived from Helix aspersa mucus in enhancing the anti-proliferative effects of chemotherapy drugs in breast cancer treatment. The identification of additive interactions provides insights into the development of combination therapies with reduced drug dosage. Overall, this study contributes to the understanding of the anti-proliferative effects of Helix aspersa mucus fractions and their interactions with chemotherapy drugs, highlighting their potential as novel therapeutic approaches in breast cancer treatment.

Safety and Effectiveness of Trastuzumab Biosimilar SB3 in Korean Patients, a Post-Marketing Surveillance Study

Introduction: SB3 is a trastuzumab biosimilar approved in Australia, Brazil, Canada, the European Union, the Republic of Korea, Switzerland, and the USA. This real-world study evaluated safety and effectiveness of SB3 as part of the Korean post approval safety management system. Methods: This post-marketing surveillance in Korea included patients in line with approved indications, i.e., patients with early or metastatic breast cancer or metastatic gastric cancer. Safety outcomes were adverse events (AEs) and adverse drug reactions. Effectiveness outcomes were tumor response and event-free survival. Results: 424 patients were evaluated: 366 patients (86%) with early breast cancer, 53 patients (13%) with metastatic breast cancer, and 5 patients (1%) with metastatic gastric cancer. Among patients with breast cancer, AEs (mostly mild) and adverse drug reactions were reported by 158 (37.7%) and 57 (13.6%) patients, respectively. Most patients with an AE (141, 89.2%) had no change in treatment schedule. Treatment was temporarily suspended in 14 (8.9%) patients with an AE and completely discontinued in 7 (4.4%). Among patients with early and metastatic breast cancer who were evaluated for efficacy, objective response rates were 82.7% and 38.3%, respectively. Pathological complete response was 64.6% in patients with early breast cancer. Discussion/Conclusion: Safety and efficacy of SB3 demonstrated in this real-world study were comparable with previous studies of reference trastuzumab.

Ag nanoparticles anchored onto Graphene Oxide for the ultrasensitive detection of exemestane as a Breast cancer drug in pharmaceutical, water sources and agricultural waste

Ag nanoparticles anchored onto Graphene Oxide for the ultrasensitive detection of exemestane as a Breast cancer drug in pharmaceutical, water sources and agricultural waste

Synthesis of potent MDA-MB 231 breast cancer drug molecules from single step

We have prepared novel potent breast cancer drug molecules from non-toxic and inexpensive method. Column chromatography is not necessary for purification of target molecules. The value of overall atom economy, environmental factor, environmental catalyst and product mass intensity gives additional merits for this synthetic method. Synthesized flexible dimeric imidazolium bromides showed less toxicity and gives excellent anticancer response against normal mammary epithelial cells. Novel dimeric pyridinium bromides showed excellent anticancer response against tested cancer cell lines. In cell cycle, novel flexible dimeric pyridinium bromides showed significant arrest in the G2/M phase by nearly three folds, when compared with control drug. We have studied the targeting epidermal growth factor receptor for all the synthesized flexible amino substituted and methyl substituted dimeric pyridinium bromides.

Identification of an exosome-related signature associated with prognosis and immune infiltration in breast cancer

Exosomes, nanosized vesicles, play a vital role in breast cancer (BC) occurrence, development, and drug resistance. Hence, we proceeded to study the potential prognostic value of exosome-related genes and their relationship to the immune microenvironment in BC. 121 exosome-related genes were provided by the ExoBCD database, and 7 final genes were selected to construct the prognostic signature. Besides, the expression levels of the 7 exosome-related genes were validated by the experiment in BC cell lines. Based on the signature, BC patients from the training and validation cohorts were separated into low- and high-risk groups. Subsequently, the R clusterProfiler package was applied to identify the distinct enrichment pathways between high-risk groups and low-risk groups. The relevance of the tumor immune microenvironment and exosome-related gene risk score were analyzed in BC. Eventually, the different expression levels of immune checkpoint-related genes were compared between the two risk groups. Based on the risk model, the low-risk groups were identified with a higher survival rate both in the training and validation cohorts. A better overall survival was revealed in patients with higher scores evaluated by the estimation of stromal and immune cells in malignant tumor tissues using expression (ESTIMATE) algorithm. Subsequently, BC patients with lower risk scores were indicated by higher expression levels of some immune checkpoint-related genes and immune cell infiltration. Exosomes are closely associated with the prognosis and immune cell infiltration of BC. These findings may contribute to improving immunotherapy and provide a new vision for BC treatment strategies.