Disseminated Breast Cancer Research Articles

Breast cancer stem cells origins and the memory stem cells: clinical significance of biomarkers and the active therapeutic approaches

Despite recent improvements in diagnosis and treatment, breast cancer (BC) remains one of the leading causes of cancer-related deaths among women. In this complex disease, breast cancer stem cells (BCSCs) are a small but significant subset of different cancer cells with the ability to proliferate and self-renew. According to an increasing amount of studies, BCSCs are essential for breast cancer metastasis, drug resistance, and recurrence. Due to its diverse nature, BC includes numerous subtypes, each of which displays unique BCSC types and concentrations that are connected to different therapy outcomes and outcomes. Despite significant advancements in the treatment of early-stage breast cancer, there are still few effective therapy approaches for metastatic BC. The development, progression, and dissemination of BC are largely attributed to cancer stem-like cells (CSCs), which are characterized by their exceptional adaptability and self-renewal ability. An overview of the development of BCSCs, their biomarkers, clinical significance, and the mechanisms behind their behavior is the goal of the current study. The active therapy strategies being employed to address BCSCs will also be examined.

Class Effect Unveiled: PPARγ Agonists and MEK Inhibitors in Cancer Cell Differentiation.

Epithelial-to-mesenchymal transition (EMT) plays a major role in breast cancer progression and the development of drug resistance. We have previously demonstrated a trans-differentiation therapeutic approach targeting invasive dedifferentiated cancer cells. Using a combination of PPARγ agonists and MEK inhibitors, we forced the differentiation of disseminating breast cancer cells into post-mitotic adipocytes. Utilizing murine breast cancer cells, we demonstrated a broad class effect of PPARγ agonists and MEK inhibitors in inducing cancer cell trans-differentiation into adipocytes. Both Rosiglitazone and Pioglitazone effectively induced adipogenesis in cancer cells, marked by PPARγ and C/EBPα upregulation, cytoskeleton rearrangement, and lipid droplet accumulation. All tested MEK inhibitors promoted adipogenesis in the presence of TGFβ, with Cobimetinib showing the most prominent effects. A metastasis ex vivo culture from a patient diagnosed with triple-negative breast cancer demonstrated a synergistic upregulation of PPARγ with the combination of Pioglitazone and Cobimetinib. Our results highlight the potential for new therapeutic strategies targeting cancer cell plasticity and the dedifferentiation phenotype in aggressive breast cancer subtypes. Combining differentiation treatments with standard therapeutic approaches may offer a strategy to overcome drug resistance.

The influence of polymorphism of genes associated with breast cancer on the effectiveness of drug antitumor therapy

Background. Increasing the survival rate of breast cancer patients is a problem all over the world and directly depends on the early detection of a malignant tumor. Genome-wide associative studies (GWAS) as a minimally invasive method may be used in determining risk of breast cancer or detection at an early stage. The increase in the number of patients with disseminated breast cancer in the Republic of Kazakhstan makes it necessary to search for molecular genetic markers of breast cancer for their use in the diagnosis and treatment of patients with this pathology.Aim. To retrospectively estimate the correlation of the effectiveness of drug antitumor therapy for breast cancer with gene polymorphism.Materials and methods. The study included the results of genotyping biomaterial samples on high-density DNA chips (venous blood of 1,277 Kazakh patients (in the third generation) with a verified diagnosis of breast cancer with locally advanced and disseminated breast cancer who received anticancer therapy), clinical data of patients, data on the clinical efficacy and toxicity of drug therapy. GWAS data (genotypes) associated with identified responses to chemotherapy drugs were compared with similar data recorded in international databases.Results. The family history study showed 16.52 % of women in the questionnaires had a family history of various types of ESR, and 86.25 % of them had a burden of breast cancer in women of the first degree of kinship. The average age of patients with breast cancer was 48.79 ± 11.44 years. According to the TNM classification, cancer in situ was detected in 4.78 % of patients, stage I of the disease was recorded in 15.27 %, stage II in 63.43 %, stage III in 12.60 %, stage IV in 3.92 % of patients. The vast majority of the patients (96.9 %) had a nodular form of breast cancer. The distribution of the patients by tumor phenotype: luminal type A was found in 20.4 % of patients, luminal type B in 38.3 %, luminal type B with HER2 overexpression in 14.3 %, HER2 positive form in 11.9 % of cases, 12.4 % of patients had an aggressive form – triple negative breast cancer. 18 main genotypes were identified in the Kazakh population as a result of the analysis of associations of the effectiveness of neoadjuvant chemotherapy (its individual components, according to chemotherapy regimens) and individual gene polymorphisms.Conclusion. An associative relationship between different types of gene polymorphism and the characteristics of response to various chemotherapeutic drugs used in the treatment of breast cancer has been confirmed. The obtained results formed the basis for the development of recommendations for making changes to the clinical practice of the Republic of Kazakhstan in order to use them in identifying a genetic predisposition to breast cancer and the effectiveness of drugs used in treatment.

Tumor Biomechanics Alters Metastatic Dissemination of Triple Negative Breast Cancer via Rewiring Fatty Acid Metabolism.

In recent decades, the role of tumor biomechanics on cancer cell behavior at the primary site has been increasingly appreciated. However, the effect of primary tumor biomechanics on the latter stages of the metastatic cascade, such as metastatic seeding of secondary sites and outgrowth remains underappreciated. This work sought to address this in the context of triple negative breast cancer (TNBC), a cancer type known to aggressively disseminate at all stages of disease progression. Using mechanically tuneable model systems, mimicking the range of stiffness's typically found within breast tumors, it is found that, contrary to expectations, cancer cells exposed to softer microenvironments are more able to colonize secondary tissues. It is shown that heightened cell survival is driven by enhanced metabolism of fatty acids within TNBC cells exposed to softer microenvironments. It is demonstrated that uncoupling cellular mechanosensing through integrin β1 blocking antibody effectively causes stiff primed TNBC cells to behave like their soft counterparts, both in vitro and in vivo. This work is the first to show that softer tumor microenvironments may be contributing to changes in disease outcome by imprinting on TNBC cells a greater metabolic flexibility and conferring discrete cell survival advantages.

METTL3 orchestrates glycolysis by stabilizing the c-Myc/WDR5 complex in triple-negative breast cancer

BackgroundThe carcinogenic transcription factor c-Myc is the most aggressive oncogene, which drive malignant transformation and dissemination of triple-negative breast cancer (TNBC). Recruitment of many cofactors, especially WDR5, a protein that nucleates H3K4me chromatin modifying complexes, play a pivotal role in regulating c-Myc-dependent gene transcription, a critical process for c-Myc signaling to function in a variety of biological and pathological contexts. For this reason, interrupting the interaction between c-Myc and the transcription cofactor WDR5 may become the most promising new strategy for treating c-Myc driven TNBC. MethodsImmunoprecipitation and mass spectrometry (IP-MS) is used to screen proteins that bind c-Myc/WDR5 interactions. The interaction of METTL3 with c-Myc/WDR5 in breast cancer tissues and TNBC cells was detected by Co-IP and immunofluorescence. Subsequently, we further analyzed the influence of METTL3 expression on c-Myc/WDR5 protein expression and its interaction stability by Western blot and Co-IP. The correlation between METTL3 and c-Myc pathway was analyzed by ChIP-seq sequencing and METTL3 knockdown transcriptome data. The effect of METTL3 expression on c-Myc transcriptional activity was detected by ChIP-qPCR and Dual Luciferase Reporter. At the same time, the overexpression vector METTL3-MUT (m6A) was constructed, which mutated the methyltransferase active site (Aa395–398, DPPW/APPA), and further explored whether the interaction between METTL3 and c-Myc/WDR5 was independent of methyltransferase activity. In addition, we also detected the changes of METTL3 expression on TNBC's sensitivity to small molecule inhibitors such as JQ1 and OICR9429 by CCK8, Transwell and clonal formation assays. Finally, we further verified our conclusions in spontaneous tumor formation mouse MMTV-PyMT and nude mouse orthotopic transplantation tumor models. ResultsMETTL3 was found to bind mainly to c-Myc/WDR5 protein in the nucleus. It enhances the stability of c-Myc/WDR5 interaction through its methyltransferase independent mechanism, thereby enhancing the transcriptional activity of c-Myc on downstream glucose metabolism genes. Notably, the study also confirmed that METTL3 can directly participate in the transcription of glucose metabolism genes as a transcription factor, and knockdown METTL3 enhances the drug sensitivity of breast cancer cells to small molecule inhibitors JQ1 and OICR9429. The study was further confirmed by spontaneous tumor formation mouse MMTV-PyMT and nude mouse orthotopic transplantation tumor models. ConclusionMETTL3 binds to the c-Myc/WDR5 protein complex and promotes glycolysis, which plays a powerful role in promoting TNBC progression. Our findings further broaden our understanding of the role and mechanism of action of METTL3, and may open up new therapeutic avenues for effective treatment of TNBC with high c-Myc expression.

Abstract 1504: Tumor microenvironment-mediated regulation of early dissemination and colonization in breast cancer via BAZ2A-containing remodeling complexes

Abstract The molecular mechanisms governing invasion, dissemination, extravasation, and early metastatic colonization remain incompletely understood. In the BALB-neuT mouse model, we found that most metastases originate from disseminated cancer cells (DCCs) that left the primary site early in tumorigenesis, i.e. when lesions are still small. Consequently, we investigated whether cellular density and the tumor microenvironment synergize to generate the plasticity needed during metastasis. RNA-sequencing analyses of murine breast cancer cells in low cellular density (LD) and high cellular density (HD) conditions revealed distinct profiles of differentially expressed genes. Notably, we identified the enrichment of ribosomal RNA (rRNA) and chromatin remodeling pathways in LD conditions. Interestingly, once these cells were treated with Wnt4 and Rankl, factors secreted by the tumor microenvironment, the expression profile of genes involved in proliferation, migration and stemness as well as epigenetic-related factors changed drastically. Specifically, cells in LD conditions treated with Wnt4 and Rankl displayed induced migration and stemness phenotypes, whereas under HD conditions, these signals induced proliferation. Among the chromatin-remodeling pathways, we found that BAZ2A along with the rRNA regulating network were primarily upregulated in migratory cancer cells. Immunostaining of primary and metastatic lesions in murine and human breast cancer samples showed an upregulation of BAZ2A in early/microlesions compared to more advanced and proliferative macroscopic lesions. Taken together, these results indicate that cell density, tumor microenvironmental factors and BAZ2A-containing chromatin regulating complexes play pivotal roles in regulating cancer cell plasticity in breast cancer. Additional sequencing and functional analyses will be performed to dissect the specific components of this mechanism and evaluate their impact on the in vivo colonization of breast cancer models. Citation Format: Miriam Kokal-Ribaudo, Nora Jahnen, Saba Sameri, Fulvia Ferrazzi, Renato Liguori, Christoph A. Klein, Gernot Längst, Hedayatollah Hosseini. Tumor microenvironment-mediated regulation of early dissemination and colonization in breast cancer via BAZ2A-containing remodeling complexes [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 1504.

Abstract 3940: Nuclear translocation of HER3 promotes breast cancer progression and dissemination recruiting immune cells via CXCL1 and CXCL8

Abstract Breast cancer is a highly complex multifactorial disease, which can be driven by the aberrant regulation of different signaling pathways including receptor tyrosine kinase (RTK) signaling. Notably, while RTKs have been classically described as transmembrane receptors, they can also translocate to the nucleus, even though the functional importance of this process remains largely unexplored for most RTKs. Here, we report a novel role for the nuclear form of the RTK human epidermal growth factor receptor 3 (HER3) in driving primary breast cancer growth and metastasis. Firstly, using different patient-derived organoids (PDOs) established from metastatic breast cancer patients, we demonstrated the robust translocation of the activated phosphorylated HER3 receptor (pHER3) from the plasma membrane to the nucleus in response to its ligand Neuregulin 1 (NRG1). Interestingly, the nuclear translocation was observed not only in the HER2-positive breast cancer subtype but also in luminal and triple-negative breast cancer-derived cells. In order to decipher the functional role of nuclear HER3 (nHER3), we identified and mutated its nuclear localization signal, resulting in decreased nuclear translocation of the receptor while its membrane form remained intact. This reduction in nHER3 remarkably impeded primary tumor growth and metastatic spread in different patient-derived xenograft (PDX) models. Conversely, selective overexpression of HER3 in the nucleus led to increased primary tumor growth and metastatic burden in vivo. In order to decipher the mechanism of action of nHER3, we performed co-immunoprecipitation followed by global mass spectrometric analysis to identify the protein binding partners of the receptor in the nucleus. Specifically, nHER3 was found to interact with different transcription factors such as the AP-2 family of transcription factors and with major chromatin remodeling complexes like the nucleosome remodeling and deacetylase (NuRD) complex, implicating its role in transcriptional regulation. Furthermore, gene expression analysis of PDOs expressing the wild-type or the mutated form of HER3 revealed the modulation of several key growth regulators such as early growth response 3 (EGR3) by nHER3. The nHER3-EGR3 axis further controlled downstream effectors like the immune chemoattractants CXCL1 and CXCL8. Accordingly, PDX from breast cancer cells overexpressing nHER3 showed significantly increased immune infiltration, suggesting a possible role of nHER3 in regulating the tumor microenvironment. Altogether, we report here a novel non-canonical role of the nuclear form of HER3 receptor in driving breast tumorigenesis, with key implications for our understanding and targeting of RTK signaling in breast cancer. Citation Format: Tasneem Cheytan, Roberto Würth, Nina Hahnen, Elisa Donato, Corinna Klein, Rebecca Weber, Daniele Colombo, Jeroen Krijgsveld, Martin Sprick, Andreas Trumpp. Nuclear translocation of HER3 promotes breast cancer progression and dissemination recruiting immune cells via CXCL1 and CXCL8 [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 3940.

Abstract 4775: Unveiling caveolin-1's crucial role in breast cancer progression and metastasis: A molecular perspective

Abstract Background: Breast cancer, particularly its metastatic form, constitutes a significant portion of oncological mortality. Caveolin-1 (Cav-1), a caveolae structural protein, has been implicated in cellular processes such as proliferation, apoptosis, autophagy, and cellular motility (aberrant in breast cancer). With its dual role as a tumor suppressor and promoter, Cav-1's function in breast cancer pathophysiology requires elucidation for potential therapeutic targeting. Methods: We utilized a syngeneic mouse model to engineer Cav-1 deficient 4T1 murine mammary carcinoma cells which mirror the characteristics of stage IV breast cancer to investigate Cav-1's role in tumor growth and metastasis. We assessed cellular proliferation and lung metastasis, compared with wild-type controls, and performed molecular analyses to evaluate epithelial and mesenchymal marker expression, stemness-related markers, and autophagy-related gene expression. Results: Cav-1 ablation corresponded with a marked decrease in tumor proliferation and lung metastasis, indicating a suppressive role in tumor progression. Molecular characterization revealed downregulated epithelial markers (E-cadherin, β-catenin), transcription factors (TWIST1/2), and stem cell markers (NANOG, OCT4, SOX2, c-MYC, SALL4), with concurrent upregulation of the mesenchymal marker vimentin. Enhanced expression of autophagy-related genes (Beclin-1, ATG5, ATG16) was also observed, suggesting a disruption in autophagic pathways. Conclusion: Our findings underscore the critical role of Cav-1 in breast cancer progression, specifically its function in suppressing metastasis and modulating cellular phenotypes. Targeting Cav-1 could represent a novel therapeutic strategy to mitigate breast cancer growth and dissemination. Further research is warranted to explore the therapeutic potential of modulating Cav-1 in breast cancer treatment. Citation Format: Rizwana Begum, Shilpa Thota, Dhirendra Pratap Singh, Naveen Chintala, Abhishek Pandit, Biplov Sapkota, Joseph Francis. Unveiling caveolin-1's crucial role in breast cancer progression and metastasis: A molecular perspective [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 4775.

Abstract 1568: Her2 promotes early dissemination of breast cancer by suppressing the p38 pathway through upregulation of Wip1

Abstract (a)Metastasis is the leading cause of cancer-related deaths. Increasing evidence shows that cancer cells can disseminate from early primary lesions that are impalpable, but the pathways are poorly understood. Her2 promotes breast cancer early dissemination by suppressing p38, but how Her2 downregulates p38 is unclear. In this study, we investigated the mechanism underlying suppression of p38 by Her2 in breast cancer early dissemination using cell models and xenograft models of early lesions of breast cancer. (b)We studied the role of Wip1, a p38 phosphatase, in disseminating phenotypes in cell line models of breast cancer early lesions, including cell motility measured in transwell assays, cell invasion measured by percentage of organoids with outward invading cells, and epithelial-to-mesenchymal transition (EMT) measured by levels of EMT markers in Western blotting analysis and immunofluorescence (IF) staining assays. (c)We demonstrate that high levels of Wip1 correlated with Her2+ status, and reduced phosphorylation of p38 and its downstream effectors MK2 and Hsp27 in tissue samples from early lesions of human breast cancer. In addition, ectopic expression of Wip1 reduced phosphorylation of p38, MK2 and Hsp27 in cell models of breast cancer early lesions.We found that Wip1 promoted migration, invasion and EMT, while Wip1 knockdown abrogated the ability of Her2 to induce these disseminating phenotypes, in cell line models of early lesion breast cancer. Thus, Wip1 induction is both sufficient, and necessary for Her2, to promote migration, invasion and EMT in early lesion breast cancer cells. In an attempt to identify the Wip1 downstream effectors involved in disseminating phenotypes, we found that ectopic expression of the constitutively active mutants of p38 reversed the ability of Wip1 to suppress MK2 and Hsp27 phosphorylation and to induce migration, invasion and EMT in early lesion breast cancer cells. These results suggest that Wip1 promotes breast cancer early dissemination by suppressing p38. We investigate the mechanism by which Her2 induces Wip1 expression. Ectopic expression of Her2 did not alter the level of Wip1 mRNA or the Wip1 protein stability, suggesting that Her2 promote Wip1 expression by regulating its translation. We are currently investigating the mechanism by which Her2 induces Wip1 translation.Moreover, inhibitors of Her2, Wip1 and Skp2 can each reduce the disseminating phenotypes in cells models of breast cancer early lesions ectopically expressing Her2, Wip1 or Skp2. (d)Our findings identify the Her2-Wip1-p38-Mk2-Hsp27 cascade as a novel mechanism mediating breast cancer early dissemination and provide a basis for new therapies targeting early metastatic dissemination in Her2+ breast cancer using inhibitors for Her2, Wip1 or Skp2. Citation Format: Nan Wang. Her2 promotes early dissemination of breast cancer by suppressing the p38 pathway through upregulation of Wip1 [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 1568.

Abstract 5535: Intracellular negative regulators of RTK-Ras-ERK signaling alter breast cancer perception of metastatic niche-derived growth factors

Abstract Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype that commonly metastasizes to distant organs, such as the lung, resulting in the poor clinical outcomes. TNBC cells commonly overexpress epidermal growth factor receptor (EGFR), a receptor tyrosine kinase (RTK) which when bound by microenvironmental growth factors, results in the activation of downstream effector kinases ERK-AKT and initiates transcriptional programs that control cell fate. Tumor cells, however, simultaneously receive many growth factor inputs from their respective microenvironments, many of which stimulate RTKs other than EGFR, that converge at ERK and AKT resulting in different transcriptional and cell fate outputs. This raises questions as to how tumor cells perceive, decode, and respond to a complex set of microenvironmental signals and what the relevance of this process may be for disease pathogenesis and treatment. To this end, our study aimed to determine how disseminated breast cancer cells perceive and respond to a complex growth factor milieu upon seeding and engraftment in the lung. Using live-cell microscopy techniques and TNBC cells carrying biosensors for ERK and Akt signaling pathways, we monitored the dynamic signaling behaviors of single tumor cells, in real-time, as they adapted to the environment in living human lung tissue. Strikingly, we found that individual disseminated tumor cells are less responsive to growth factors once seeded in the lung, as compared to outside this tissue, despite the presence of RTK stimulating ligands. We showed that partial activation of EGFR is necessary for complete activation of ERK signaling by other growth factor-RTK pairs, and expression of downstream ERK target genes, whereas AKT signaling was unaffected. Using quantitative modeling and experimentation, we showed that reshaping of ERK signaling response dynamics occurred via dysregulation of negative regulators that are dominantly controlled by EGFR signaling. Together, these results provide novel insight into how tumor cells perceive and respond to complex microenvironmental signals, which has important implications for drug targeting strategies. Citation Format: Vaibhav Murthy, Cemal Erdem, Jeremy Copperman, Marc Birtwistle, Alexander Davies. Intracellular negative regulators of RTK-Ras-ERK signaling alter breast cancer perception of metastatic niche-derived growth factors [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 5535.

Abstract 6923: Deconvolution of breast cancer dissemination and therapy resistance via single-cell transcriptional lineage tracing

Abstract Chemotherapy remains the most used systemic treatment option for triple-negative breast cancer (TNBC). Lineage tracing studies demonstrated that treatment does not significantly alter clonal composition of primary tumors (PTs). The specific transcriptional phenotype(s) conferring chemoresistance in PTs and metastasis, however, are still largely undetermined, and have not been analyzed at single-clone resolution. We first modelled clinically relevant contexts of chemoresistance in our recently published single-cell lineage tracing approach (DOI: 10.1158/0008-5472.CAN-22-2717), using the standard-of-care combination of adriamycin and cyclophosphamide (A+C) in TNBC xenografts. Treatment was administered in neoadjuvant or adjuvant settings, or both together. In all cases, surgical PT resection was followed by metastatic disease. The neoadjuvant treatment resulted into a stable disease, thus resembling a significant fraction of the treated patients. To investigate clonal and transcriptional dynamics we performed scRNAseq analysis of 12 replicates (3 matched PT-lung replicates for each condition, for a total of 24 samples). Clustering analyses revealed a separation of treatments and tissue of origin. We retrieved a large number of longitudinal clones, including rare clones with high metastatic potential, in all the experimental conditions. A+C did not significantly alter clonal abundances, neither in PTs nor in metastases. Pseudobulk transcriptional analyses revealed key transcriptional traits associated with chemoresistance. Differential expression on longitudinal clones gave insights about transcriptional features of chemoresistant and pro-metastatic clones under chemotherapy. Integration at single-clone level of cluster analysis, pseudobulk and differential expression revealed cystatin (CST) family genes as highly-enriched in the chemoresistant and pro-metastatic phenotype. We are currently validating the role of CST genes in tumor growth, dissemination and chemoresistance in vivo using a panel of specific shRNAs. In parallel, using the same experimental model, we successfully deconvoluted the metastatic cascade through a single-cell lineage tracing approach on matched PT-CTC (circulating tumor cells)-lung replicates. scRNAseq analyses of pro-metastatic, circulating and metastatic clones is ongoing. Our preliminary data showed that all the dominant clones in the metastatic lungs are also found as CTCs in the bloodstream, thus suggesting that all pro-metastatic cells are also capable of surviving in the bloodstream and reinforcing our concept of pro-metastatic clone. This approach led us to gain a complete overview around clonal and transcriptional evolution of breast cancer dissemination. Citation Format: Alberto Dalmasso, Andrea Cossa, Giulia Bertolini, Niccolò Roda, Ilaria Servidio, Francesco Antonio Tucci, Salvatore Pece, Gabriella Sozzi, Pier Giuseppe Pelicci. Deconvolution of breast cancer dissemination and therapy resistance via single-cell transcriptional lineage tracing [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 6923.

Outlook and opportunities for engineered environments of breast cancer dormancy.

Dormant, disseminated breast cancer cells resist treatment and may relapse into malignant metastases after decades of quiescence. Identifying how and why these dormant breast cancer cells are triggered into outgrowth is a key unsolved step in treating latent, metastatic breast cancer. However, our understanding of breast cancer dormancy in vivo is limited by technical challenges and ethical concerns with triggering the activation of dormant breast cancer. In vitro models avoid many of these challenges by simulating breast cancer dormancy and activation in well-controlled, bench-top conditions, creating opportunities for fundamental insights into breast cancer biology that complement what can be achieved through animal and clinical studies. In this review, we address clinical and preclinical approaches to treating breast cancer dormancy, how precisely controlled artificial environments reveal key interactions that regulate breast cancer dormancy, and how future generations of biomaterials could answer further questions about breast cancer dormancy.

Understanding female students’ risk perceptions of developing breast cancer at Great Zimbabwe University

This article focuses on breast cancer as the second most prevalent cancer in Zimbabwe. However, despite several local studies on breast cancer and its risk factors, the incidence rate of the disease in the country is increasing. This article sought to establish the level of awareness of the risk factors of breast cancer among female students. The study was carried out at Great Zimbabwe University, an institution of higher learning in Masvingo province, Zimbabwe. A mixed methods approach was employed involving a focus group discussion comprising eight key informants and online individual questionnaires with open and closed questions used to capture attitudes of female students towards breast cancer. Risk factors were categorised into age, family history, reproductive factors, oestrogen, and lifestyle. There were also some cultural beliefs like bewitchment and myths about black brassieres causing breast cancer. Thus, there is need for educative campaigns to disseminate breast cancer information, especially promoting regular screening and awareness of predisposing factors. Additionally, more regular and in-depth studies on breast cancer in Zimbabwe are imperative as our results show a higher prevalence rate than current official statistics. The research provides relevant information for pastoral caretakers handling trauma in the discipline of practical theology.Contribution: This article represents an intersection between practical theology and basic health care. Insights resulted from this study provide a baseline upon which to develop ways to reduce prevalence of breast cancer. The research can also be utilised by specialists in pastoral care and women theologies.

Growth signaling autonomy in circulating tumor cells aids metastatic seeding.

Self-sufficiency (autonomy) in growth signaling, the earliest recognized hallmark of cancer, is fueled by the tumor cell's ability to "secrete-and-sense" growth factors (GFs); this translates into cell survival and proliferation that is self-sustained by autocrine/paracrine secretion. A Golgi-localized circuitry comprised of two GTPase switches has recently been implicated in the orchestration of growth signaling autonomy. Using breast cancer cells that are either endowed or impaired (by gene editing) in their ability to assemble the circuitry for growth signaling autonomy, here we define the transcriptome, proteome, and phenome of such an autonomous state, and unravel its role during cancer progression. We show that autonomy is associated with enhanced molecular programs for stemness, proliferation, and epithelial-mesenchymal plasticity. Autonomy is both necessary and sufficient for anchorage-independent GF-restricted proliferation and resistance to anticancer drugs and is required for metastatic progression. Transcriptomic and proteomic studies show that autonomy is associated, with a surprising degree of specificity, with self-sustained epidermal growth factor receptor (EGFR)/ErbB signaling. Derivation of a gene expression signature for autonomy revealed that growth signaling autonomy is uniquely induced in circulating tumor cells (CTCs), the harshest phase in the life of tumor cells when it is deprived of biologically available epidermal growth factor (EGF). We also show that autonomy in CTCs tracks therapeutic response and prognosticates outcome. These data support a role for growth signaling autonomy in multiple processes essential for the blood-borne dissemination of human breast cancer.

The use of ribociclib in real clinical practice: results of a single-center observational retrospective study

Introduction. The standard initial treatment for patients with hormone receptor positive, HER2 negative, metastatic breast cancer (HR+/HER2– mBC) involves the use of CDK4/6 inhibitors (CDK4/6i) in combination with endocrine therapy. The combination therapy has proven effectiveness in numerous Phase II and III randomized controlled trials (RCTs). Nonetheless, RCTs may not fully represent real-world clinical situations due to their stringent inclusion criteria, resulting in a specific patient population.Aim. Analyze of ribociclib using for treating patients with HR+/HER2– advanced breast cancer (mBC) at the Republican Clinical Oncology Dispensary.Materials and methods. Patients diagnosed with HR+/HER2– mBC who were treated in clinical routine with ribociclib in combination with different endocrine agents between 2016 and 2020 were identified and enrolled in this retrospective study. Clinicopathological characteristics and clinical outcomes were recorded with particular emphasis on ribociclib therapy course (progression-free survival (PFS), toxicity, dose reduction).Results. Data from n = 101 patients were evaluated. The mean patient age was 61 years. The study included 67 (66.3%) patients with progression after radical treatment and 34 (33.7%) patients with primary disseminated breast cancer. Dose reduction due to adverse events was performed in n = 14 cases (13.9%). Presence of prior therapy lines and lower ECOG status were associated with shorter PFS, whereas estrogen positivity and the choice of fulvestrant over aromatase inhibitor were positively associated with PFS. Metastatic pattern, progesterone positivity and dose reduction due to toxicity did not significantly impact on PFS.Conclusion. Our real-world data analysis on ribociclib treatment in Russian regional hospital supports data from RCTs regarding both treatment efficacy and safety of CDK4/6i for treatment of patients with HR+/HER2– mBC. Currently, by expanding our experience with CDK4/6 inhibitors in different groups of patients with mBC, we will be able to provide patients with optimal treatment options.

Unleashing the power of AI: Assessing the reliability of ChatGPT in disseminating breast cancer awareness.

ChatGPT is a large language model that can initiate conversations with humans and respond to their questions. Due to its access to vast amounts of text data, it has the potential to offer health information. This study will explore the ability of ChatGPT to disseminate health information on breast cancer to draw predictions on its acceptance and utilization as a portal for breast cancer awareness. Through the Technology Acceptance Model that focuses on two main aspects, the ease of use and the usefulness, a qualitative comparative analysis was conducted to assess breast cancer information retrieved from ChatGPT and the Centers for Disease Control and Prevention (CDC) website. Common queries that patients with breast cancer and the public often ask were used for assessment. A checklist of the essential elements covered by each question was created. Four themes (definition, prevention, diagnostics, and therapeutics) were used for the coding process and truth tables were created to compare answers. Results showed that the design of ChatGPT renders it an easy platform to initiate conversation and obtain clarifications and explanations for ideas and questions instantaneously. ChatGPT provides adequate and correct information on breast cancer compared to the CDC website, collects information from multiple authentic resources, and provides better access to information. Nevertheless, ChatGPT lacks accountability, and the nature of its responses changes over time. Overall, ChatGPT is a promising medium for the dissemination of health information on breast cancer and an important tool for raising awareness and improving public health knowledge on the disease.

Needle biopsy accelerates pro-metastatic changes and systemic dissemination in breast cancer: Implications for mortality by surgery delay

Increased breast cancer (BC) mortality risk posed by delayed surgical resection of tumor after diagnosis is a growing concern, yet the underlying mechanisms remain unknown. Our cohort analyses of early-stage BC patients reveal the emergence of a significantly rising mortality risk when the biopsy-to-surgery interval was extended beyond 53days. Additionally, histology of post-biopsy tumors shows prolonged retention of a metastasis-permissive wound stroma dominated by M2-like macrophages capable of promoting cancer cell epithelial-to-mesenchymal transition and angiogenesis. We show that needle biopsy promotes systemic dissemination of cancer cells through a mechanism of sustained activation of the COX-2/PGE2/EP2 feedforward loop, which favors M2 polarization and its associated pro-metastatic changes but are abrogated by oral treatment with COX-2 or EP2 inhibitors in estrogen-receptor-positive (ER+) syngeneic mouse tumor models. Therefore, we conclude that needle biopsy of ER+ BC provokes progressive pro-metastatic changes, which may explain the mortality risk posed by surgery delay after diagnosis.

Mathematical Modeling of Breast Cancer Based on the Caputo–Fabrizio Fractal-Fractional Derivative

Breast cancer ranks among the most prevalent malignancies affecting the female population and is a prominent contributor to cancer-related mortality. Mathematical modeling is a significant tool that can be employed to comprehend the dynamics of breast cancer progression and dissemination and to formulate novel therapeutic approaches. This paper introduces a mathematical model of breast cancer that utilizes the Caputo–Fabrizio fractal-fractional derivative. The aim is to elucidate and comprehend the intricate dynamics governing breast cancer cells and cytotoxic T lymphocytes in the context of the fractional derivative. The derivative presented herein offers a broader perspective than the conventional derivative, as it incorporates the intricate fractal characteristics inherent in the process of tumor proliferation. The significance of this study lies in its contribution to a novel mathematical model for breast cancer, which incorporates the fractal characteristics of tumor development. The present model possesses the capability to investigate the impacts of diverse treatment strategies on the proliferation of breast cancer, as well as to formulate novel treatment strategies that exhibit enhanced efficacy.

Influence of anesthetic blockades on recurrence and spread of breast cancer

IntroductionHistorically, pathological and laboratory factors are considered in the prognosis of breast cancer. Tumor resection surgery constitutes the main treatment, but paradoxically, the surgical manipulation and perioperative immunosuppression may predispose to cancer dissemination. Locoregional anesthetic techniques would avoid this immunosuppression, thus improving the oncologic outcomes of surgery. This study aimed to evaluate the prognostic influence of locoregional anesthesia on breast cancer dissemination and recurrence after surgery. MethodsA retrospective cohort study was performed on 165 centrolobulillar breast cancer patients, scheduled for non-reconstructive breast oncologic surgery between 2012 and 2015. These patients were treated with conservative surgery under general anesthesia (control group, n = 81) or combined anesthesia with a locoregional block (n = 84). Data were collected on age, tumor type (size, stage, lymph node infiltration), immunohistochemical factors (hormone receptors), procedure (duration, technique), anesthesia (general anesthesia or associated with regional blockade), complications, survival, and recurrence. ResultsStatistical analysis demonstrated no significative differences in age, weight, sex, ASA status, and surgical technique and duration. Tumor recurrence was recorded in 6 patients (4 in the general group and 2 in the locoregional group) 1 year after surgery, and 6 (4 in the general group and 2 in the locoregional group) 5 years after. No significant differences between groups in morbi-mortality were found. ConclusionsFollowing the interfascial analgesic technique, a lower rate of tumor recurrence was observed, but no significant differences.

Categorization and Analysis of Primary Care mHealth Apps Related to Breast Health and Breast Cancer: Systematic Search in App Stores and Content Analysis.

Breast cancer is the most common cause of cancer mortality among women globally. The use of mobile health tools such as apps and games is increasing rapidly, even in low- and middle-income countries, to promote early diagnosis and to manage care and support of survivors and patients. The primary objective of this review was to categorize selected mobile health apps related to breast health and prevention of breast cancer, based on features such as breast self-examination (BSE) training and reminders, and to analyze their current dissemination. An ancillary objective was to highlight the limitations of existing tools and suggest ways to improve them. We defined strict inclusion and exclusion criteria, which required apps to have titles or descriptions that suggest that they were designed for the general public, and not for patients with breast cancer or health workers. Apps that focused on awareness and primary care via self-check were included, while those that focused on topics such as alternative treatments and medical news were excluded. Apps that were not specifically related to breast cancer were also excluded. Apps (in any language) that appeared in the search with keywords were included. The database consisted of apps from AppAgg and Google Play Store. Only 85 apps met the inclusion criteria. Selected apps were categorized on the basis of their alleged interactive features. Descriptive statistics were obtained, and available language options, the number of downloads, and the cost of the apps were the main parameters reviewed. The selected apps were categorized on the basis of the following features: education, BSE training, reminders, and recording. Of the 85 selected apps, 72 (84.7%) focused on disseminating breast cancer information. BSE training was provided by only 47% (n=40) of the apps, and very few had reminder (n=26, 30.5%) and recording (n=11, 12.9%) features. The median number of downloads was the highest for apps with recording features (>1000 downloads) than those with education, BSE training, reminder, and recording features (>5000 downloads). Most of these apps (n=74, 83.5%) were monolingual, and around 80.3% (n=49) of these apps were in English. Almost all the apps on Google Play Store were free of charge. Although there exist several apps on Google Play Store to promote awareness about breast health and cancer, the usefulness of most of them appears debatable. To provide a complete breast health package to the users, such apps must have all of the following features: reminders or notifications and symptom recording and tracking. There is still an urgent need to scientifically evaluate existing apps in the target populations in order to make them more functional and user-friendly.