Molecular Subtypes and Local-Regional Control of Breast Cancer

Texture analysis using non-contrast MRI to predict estrogen receptor status in breast cancer lesions: Is it feasible?

PURPOSE

We aimed to evaluate the feasibility of non-contrast-enhanced T1 sequence in texture analysis of breast cancer lesions to predict their estrogen receptor status.

METHODS

The study included 85 pathologically proven breast cancer lesions in 53 patients. Immunohistochemical studies were performed to determine the estrogen receptor status (ER). Lesions were divided into two groups: ER + ve status and ER-ve status. Texture analysis using the second-order analysis features [The Co-occurrence matrix (11 features)] was applied on both T1 and dynamic contrast-enhanced (DCE) MRI images for each lesion. Texture features gained from both T1 and DCE images were analyzed to obtain cut-off values using ROC curves to sort lesions according to their estrogen receptor status.

RESULTS

Angular second momentum and some of the entropy-based features showed statistically significant cut-off values in differentiation between the two groups [P-values for pre- and post-contrast images for AngSecMom (0.001, 0.008), sum entropy (0.003,0.005), and entropy (0.033,0.019), respectively]. On comparing the AUCs between pre- and post-contrast images, we found that differences were statistically insignificant. Sum of squares, sum variance, and sum average showed statistically significant cut-off points only on pre-contrast images [P-values for sum of squares (0.018), sum variance (0.024), and sum average (0.039)].

CONCLUSIONS

Texture analysis features showed promising results in predicting estrogen receptor status of breast cancer lesions on non-contrast T1 images.

HER2/PI3K/AKT pathway in HER2-positive breast cancer: A review

Breast cancer is currently the most commonly occurring cancer globally. Among breast cancer cases, the human epidermal growth factor receptor 2 (HER2)-positive breast cancer accounts for 15% to 20% and is a crucial focus in the treatment of breast cancer. Common HER2-targeted drugs approved for treating early and/or advanced breast cancer include trastuzumab and pertuzumab, which effectively improve patient prognosis. However, despite treatment, most patients with terminal HER2-positive breast cancer ultimately suffer death from the disease due to primary or acquired drug resistance. The prevalence of aberrantly activated the protein kinase B (AKT) signaling in HER2-positive breast cancer was already observed in previous studies. It is well known that p-AKT expression is linked to an unfavorable prognosis, and the phosphatidylinositol-3-kinase (PI3K)/AKT pathway, as the most common mutated pathway in breast cancer, plays a major role in the mechanism of drug resistance. Therefore, in the current review, we summarize the molecular alterations present in HER2-positive breast cancer, elucidate the relationships between HER2 overexpression and alterations in the PI3K/AKT signaling pathway and the pathways of the alterations in breast cancer, and summarize the resistant mechanism of drugs targeting the HER2-AKT pathway, which will provide an adjunctive therapeutic rationale for subsequent resistance to directed therapy in the future.

Epigenetic regulation of breast cancer metastasis

Breast cancer is the most frequently diagnosed malignancy and the second leading cause of cancer-related mortality among women worldwide. Recurrent metastasis is associated with poor patient outcomes and poses a significant challenge in breast cancer therapies. Cancer cells adapting to a new tissue microenvironment is the key event in distant metastasis development, where the disseminating tumor cells are likely to acquire genetic and epigenetic alterations during the process of metastatic colonization. Despite several decades of research in this field, the exact mechanisms governing metastasis are not fully understood. However, emerging body of evidence indicates that in addition to genetic changes, epigenetic reprogramming of cancer cells and the metastatic niche are paramount toward successful metastasis. Here, we review and discuss the latest knowledge about the salient attributes of metastasis and epigenetic regulation in breast cancer and crucial research domains that need further investigation.

Influence of tumor microenvironment on the different breast cancer subtypes and applied therapies

Despite the significant improvements made in breast cancer therapy during the last decades, this disease still has increasing incidence and mortality rates. Different targets involved in general processes, like cell proliferation and survival, have become alternative therapeutic options for this disease, with some of them already used in clinic, like the CDK4/6 inhibitors for luminal A tumors treatment. Nevertheless, there is a demand for novel therapeutic strategies focused not only on tumor cells, but also on their microenvironment. Tumor microenvironment (TME) is a very complex and dynamic system that, more than surrounding and supporting tumor cells, actively participates in tumor development and progression. During the last decades, it has become clear that the cellular and acellular components of TME differ between the various breast cancer subtypes and shape the differences regarding their severity and prognosis. The pivotal role of the TME in controlling tumor growth and influencing responses to therapy represents a potential source for novel targets and therapeutic strategies. In this review, we present a description of the multiple therapeutic options used for different breast cancer subtypes, as well as the influence that the TME may exert on the development of the disease and on the response to the distinct therapies, which in some cases may explain their failure by the occurrence of relapses and resistance. Furthermore, the ongoing studies focused on the use of TME components for developing potential cancer treatments are described.

Breast cancer therapy: from the perspective of glucose metabolism and glycosylation

Breast cancer is a leading cause of mortality and the most prevalent form of malignant tumor among women worldwide. Breast cancer cells exhibit an elevated glycolysis and altered glucose metabolism. Moreover, these cells display abnormal glycosylation patterns, influencing invasion, proliferation, metastasis, and drug resistance. Consequently, targeting glycolysis and mitigating abnormal glycosylation represent key therapeutic strategies for breast cancer. This review underscores the importance of protein glycosylation and glucose metabolism alterations in breast cancer. The current research efforts in developing effective interventions targeting glycolysis and glycosylation are further discussed.

Troponin T1 silencing inhibits paclitaxel resistance and the development of breast cancer via suppressing rat sarcoma virus/rapidly accelerated fibrosarcoma 1 pathway

OBJECTIVE

We aimed to determine the role of Troponin T1 (TNNT1) in paclitaxel (PTX) resistance and tumor progression in breast cancer (BC).

METHODS

Differentially expressed genes were obtained from the GSE4298 and GSE90564 datasets. Hub genes were isolated from protein-protein interaction networks and further validated by real-time quantitative polymerase chain reaction. The effect of TNNT1 on PTX resistance was determined using cell counting kit-8, 5-ethynyl-2'-deoxyuridine, wound healing, transwell, flow cytometry assays, and subcutaneous xenografted tumor model. Western blotting was used to detect proteins associated with PTX resistance, apoptosis, migration, invasion, and other key pathways. Hematoxylin-eosin and immunohistochemical staining were used to evaluate the role of TNNT1 in tumors.

RESULTS

After comprehensive bioinformatic analysis, we identified CCND1, IGF1, SFN, INHBA, TNNT1, and TNFSF11 as hub genes for PTX resistance in BC. TNNT1 plays a key role in BC and is upregulated in PTX-resistant BC cells. TNNT1 silencing inhibited PTX resistance, proliferation, migration, and invasion while promoting apoptosis of PTX-resistant BC cells. Tumor xenograft experiments revealed that TNNT1 silencing suppresses PTX resistance and tumor development in vivo. In addition, TNNT1 silencing inhibited the expression of proteins in the rat sarcoma virus (RAS)/rapidly accelerated fibrosarcoma1 (RAF1) pathway in vivo. Treatment with a RAS/RAF1 pathway activator reversed the inhibitory effect of TNNT1 silencing on proliferation, migration, and invasion while promoting apoptosis of PTX resistance BC cells.

CONCLUSION

Silencing of TNNT1 suppresses PTX resistance and BC progression by inhibiting the RAS/RAF1 pathway, which is a promising biomarker and therapeutic target for drug resistance in BC.

Traditional Clinicopathological Biomarkers Still Determine Disease-Free and Overall Survival in Invasive Breast Cancer Patients: A Pilot Study

Background: Molecular classification, tumor diameter, Ki67 expression, and brachytherapy administration still act as the most potent potential predictors of breast cancer recurrence and overall survival. Methods: Over the period of 23 months, we included in the study 92 invasive breast cancer (IBrC) patients initially diagnosed at the Clinical Ward of Breast Cancer and Reconstructive Surgery, Oncology Center in Bydgoszcz, Poland. The probability of disease-free survival (DFS) and overall survival (OS) in relation to potential prognostic factors for the patients were determined using a Kaplan-Meier analysis, and univariate and multivariate Cox regression analyses evaluated the predictive factors of IBrC patients. The investigation of the potential prognostic model's accuracy was analyzed using the ROC curve. Results: Patients with tumor size < 2 cm, Ki67 expression < 20%, luminal-A molecular subtype, and extra-dose brachytherapy boost administration displayed the most favorable prognosis according to breast cancer disease-free survival and overall survival. The estimated 5 year probability of DFS and OS rates in women with tumor diameter < 2 cm were 89% and 90%, respectively. In tumor diameter > 2 cm, the estimated 5 year probability of DFS was 73% and OS was 76%. Interestingly, the tumor diameter of 1.6 cm with a specificity of 60.5% and a sensitivity of 75% occurred as the best threshold point to differentiate patients with cancer recurrence from those without cancer progression. Conclusions: Our study provides essential information on the clinicopathological profile and future outcomes of early stage IBrC patients. Furthermore, the tumor diameter cut-off value of 1.6 cm discriminating between disease recurrence and those without disease progression patients represents an innovative direction for further research.

(E)-2-Methoxy-4-(3-(4-Methoxyphenyl) Prop-1-en-1-yl) Phenol Suppresses Breast Cancer Progression by Dual-Regulating VEGFR2 and PPARγ

In cancer treatment, multi-target approach has paid attention to a reasonable strategy for the potential agents. We investigated whether (E)-2-methoxy-4-(3-(4-methoxyphenyl) prop-1-en-1-yl) phenol (MMPP) could exert an anticancer effect by dual-regulating VEGFR2 and PPARγ. MMPP showed modulating effects in TNBC type (MDA-MB-231 and MDA-MB-468) and luminal A type (MCF7) breast cancer cell lines. MMPP enhanced PPARγ transcriptional activity and inhibited VEGFR2 phosphorylation. MMPP-induced signaling by VEGFR2 and PPARγ ultimately triggered the downregulation of AKT activity. MMPP exhibited anticancer effects, as evidenced by growth inhibition, inducement of apoptosis, and suppression of migration and invasion. At the molecular level, MMPP activated pro-apoptotic proteins (caspase3, caspase8, caspase9, and bax), while inhibiting the anti-apoptotic proteins (bcl2). Additionally, MMPP inhibited the mRNA expressions of EMT-promoting transcription factors. Therefore, our findings showed molecular mechanisms of MMPP by regulating VEGFR2 and PPARγ, and suggested that MMPP has potential to treat breast cancer.

Androgen and Estrogen β Receptor Expression Enhances Efficacy of Antihormonal Treatments in Triple-Negative Breast Cancer Cell Lines

The triple-negative breast cancer (TNBC) subtype is characterized by the lack of expression of ERα (estrogen receptor α), PR (progesterone receptor) and no overexpression of HER-2. However, TNBC can express the androgen receptor (AR) or estrogen receptor β (ERβ). Also, TNBC secretes steroid hormones and is influenced by hormonal fluctuations, so the steroid inhibition could exert a beneficial effect in TNBC treatment. The aim of this study was to evaluate the effect of dutasteride, anastrozole and ASP9521 in in vitro processes using human TNBC cell lines. For this, immunofluorescence, sensitivity, proliferation and wound healing assays were performed, and hormone concentrations were studied. Results revealed that all TNBC cell lines expressed AR and ERβ; the ones that expressed them most intensely were more sensitive to antihormonal treatments. All treatments reduced cell viability, highlighting MDA-MB-453 and SUM-159. Indeed, a decrease in androgen levels was observed in these cell lines, which could relate to a reduction in cell viability. In addition, MCF-7 and SUM-159 increased cell migration under treatments, increasing estrogen levels, which could favor cell migration. Thus, antihormonal treatments could be beneficial for TNBC therapies. This study clarifies the importance of steroid hormones in AR and ERβ-positive cell lines of TNBC.

Routine molecular applications and recent advances in breast cancer diagnostics

Cancer stands as one of the most common and lethal diseases, imposing a substantial burden on global mortality rates. Breast cancer is distinct from other forms of cancer in which it is the primary cause of death for women. Early detection of breast cancer can significantly lower the risk of mortality, improving the prognosis for those who are affected. The death rate of breast cancer has been steadily rising, according to epidemiological data, especially since the COVID-19 pandemic. This emphasizes the necessity of sensitive and precise technologies that can be utilized in early breast cancer diagnosis. In this process, biomarkers play a pivotal role by facilitating the early detection and diagnosis of breast cancer. Currently, a wide variety of cancer biomarkers have been identified, improving the accuracy of cancer diagnosis. These biomarkers can be applied in liquid biopsies as well as on solid tissues. In the context of breast cancer, biomarkers are particularly valuable for determining who is predisposed to the disease, predicting prognosis at the time of diagnosis, and selecting the best course of therapy. This review comprehensively explores the recently developed gene-based biomarkers from biofluids that are used in the context of breast cancer, as well as the conventional and cutting-edge techniques that have been employed for breast cancer diagnosis.

Cancer associated fibroblasts modulate the cytotoxicity of anti-cancer drugs in breast cancer: An in vitro study

BACKGROUND

Tumour microenvironment (TME) contributes to resistance to anti-cancer drugs through multiple mechanisms including secretion of pro-survival factors by cancer associated fibroblasts (CAFs). In this study, we determined the chemotherapy resistance producing potential of CAFs in molecular subtypes of breast cancer.

METHODS

The CAFs were isolated from fresh lumpectomy/mastectomy specimens of different molecular subtypes of breast cancer. The CAFs were cultured and secretome was collected from each breast cancer subtype. Breast cancer cell lines MCF-7, SK-BR3, MDA-MB-231, and MDA-MB-468 were treated with different doses of tamoxifen, trastuzumab, cisplatin, and doxorubicin alone respectively and in combination with secretome of CAFs from respective subtypes. MTT assay was done to check cell death after drug treatment. Liquid chromatography-mass spectrometry (LCMS) analysis of CAF secretome was also done.

RESULTS

MTT assay showed that anti-cancer drugs alone had growth inhibitory effect on the cancer cells however, presence of CAF secretome reduced the anti-cancer effect of the drugs. Resistant to drugs in the presence of secretome, was determined by increased cell viability i.e., MCF-7, 51.02% to 63.02%; SK-BR-3, 34.22% to 44.88%; MDA-MB-231, 52.59% to 78.63%; and MDA-MB-468, 48.92% to 55.08%. LCMS analysis of the secretome showed the differential abundance of CAFs secreted proteins across breast cancer subtypes.

CONCLUSIONS

The treatment of breast cancer cell lines with anti-cancer drugs in combination with secretome isolated from molecular subtype specific CAFs, reduced the cytotoxic effect of the drugs. In addition, LCMS data also highlighted different composition of secreted proteins from different breast cancer associated fibroblasts. Thus, TME has heterogenous population of CAFs across the breast cancer subtypes and in vitro experiments highlight their contribution to chemotherapy resistance which needs further validation.

Biomarker potential of the LEF1/TCF family members in breast cancer: Bioinformatic investigation on expression and clinical significance

The LEF1/TCF transcription factor family is related to the development of diverse tissue types, including the mammary tissue, and dysregulation of its expression and function has been described to favor breast tumorigenesis. However, the clinical and biological relevance of this gene family in breast cancer is still poorly understood. Here, we used bioinformatics approaches aiming to reduce this gap. We investigated its expression patterns in molecular and immune breast cancer subtypes; its correlation with immune cell infiltration, and its prognostic values in predicting outcomes. Also, through regulons construction, we determined the genes whose expression is influenced by these transcription factors, and the pathways in which they are involved. We found that LEF1 and TCF3 are over-expressed in breast tumors regarding non-tumor samples, while TCF4 and TCF7 are down-expressed, with the gene's methylation status being associated with its expression dysregulation. All four transcription factors presented significance at the diagnostic and prognostic levels. LEF1, TCF4, and TCF7 presented a significant correlation with immune cell infiltration, being associated with the immune subtypes of less favorable outcomes. Altogether, this research contributes to a more accurate understanding of the expression and clinical and biomarker significance of the LEF1/TCF transcription factors in breast cancer.

Advances in Cancer Vaccine Research

The use of cancer vaccines is considered a promising therapeutic strategy in clinical oncology, which is achieved by stimulating antitumor immunity with tumor antigens delivered in the form of cells, peptides, viruses, and nucleic acids. The ideal cancer vaccine has many advantages, including low toxicity, specificity, and induction of persistent immune memory to overcome tumor heterogeneity and reverse the immunosuppressive microenvironment. Many therapeutic vaccines have entered clinical trials for a variety of cancers, including melanoma, breast cancer, lung cancer, and others. However, many challenges, including single antigen targeting, weak immunogenicity, off-target effects, and impaired immune response, have hindered their broad clinical translation. In this review, we introduce the principle of action, components (including antigens and adjuvants), and classification (according to applicable objects and preparation methods) of cancer vaccines, summarize the delivery methods of cancer vaccines, and review the clinical and theoretical research progress of cancer vaccines. We also present new insights into cancer vaccine technologies, platforms, and applications as well as an understanding of potential next-generation preventive and therapeutic vaccine technologies, providing a broader perspective for future vaccine design.

The cytotoxic potential of sinapic acid on luminal A breast cancer; a computational and experimental pharmacology approach

Breast cancer is a highly concerning and prevalent disease that impacts a significant proportion of women worldwide, whose repeated exposure to therapies leads to resistance for drugs; making it alarming to identify novel chemotherapeutic agents. Sinapic acid is a phenolic acid that occurs naturally and is known to exhibit cytotoxic action in a variety of cancer cell types. In the present study, we utilized cell cytotoxicity assays to assess the cytotoxic potential of sinapic acid on various breast cancer subtypes. In addition, we assessed the cell migration rate, cell apoptosis, and cell cycle phases. Moreover, we utilized multiple system biology tools to predict the potential targets, and molecular docking was performed on the hub targets followed by molecular dynamic (MD) simulations. Cytotoxicity assay was performed on cell lines MCF7, T47D, MDA-MB-468, and SKBR3 at different time exposures of 24, 48, and 96 h. Our results revealed sinapic acid to be potent on MCF7 and T47D cell lines. The cell cycle analysis and cell apoptotic assays revealed sinapic acid to cause cell death by apoptosis majorly in the G0/G1 phase. Computational biology revealed KIF18B and VKORC1 to possess the highest binding affinity of -6.5 and -7.5 kcal/mol; displayed stable trajectories on MD run. The cytotoxicity of sinapic acid on luminal A cell lines may be due to the modulation of VKORC1 and KIF18B with major cell death in the G0/G1 phase. However, the mechanism has been proposed via in silico tools, which need further validation using wet lab protocols.Communicated by Ramaswamy H. Sarma.

Silibinin: an inhibitor for a high-expressed BCL-2A1/BFL1 protein, linked with poor prognosis in breast cancer

Breast cancer (BC) accounts for 30% of all diagnosed cases of cancer in women and remains a leading cause of cancer-related deaths among women worldwide. The current study looks for a protein from the anti-apoptotic/pro-survival BCL-2 family whose overexpression reduces survivability in BC patients and a potential inhibitor for the protein. We found BCL-2A1/BFL1 protein with high expression linked to low survivability in BC. The protein shows prognosis in 8 out of 29 categories, whereas no other family member manifests this property. Out of 7379 compounds, three small molecules (CHEMBL9509, CHEMBL2104550 and CHEMBL3545011) form an H-bond with BCL-2A1/BFL1 protein's unique residue Cys55. Of the three small molecules, we found CHEMBL9509 (Silibinin) to be a potent inhibitor. The compound forms a stable H-bond with the residue Cys55 with the lowest binding energy compared to the other two compounds. It remains stable in the BH3 binding region for more than 100 ns, whereas the other two detach from the region. Additionally, the compound is found to be better than Venetoclax and Nematoclax. We firmly believe in the compound CHEMBL9509 potency to halt BC's progression by inhibiting the BCL-2A1/BFL1 protein, increasing patients' survivability.Communicated by Ramaswamy H. Sarma.

Extracellular Vesicles in Triple-Negative Breast Cancer: Immune Regulation, Biomarkers, and Immunotherapeutic Potential

Triple-negative breast cancer (TNBC) is an aggressive subtype accounting for ~10-20% of all human BC and is characterized by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) amplification. Owing to its unique molecular profile and limited targeted therapies, TNBC treatment poses significant challenges. Unlike other BC subtypes, TNBC lacks specific molecular targets, rendering endocrine therapies and HER2-targeted treatments ineffective. The chemotherapeutic regimen is the predominant systemic treatment modality for TNBC in current clinical practice. However, the efficacy of chemotherapy in TNBC is variable, with response rates varying between a wide range of patients, and the emerging resistance further adds to the difficulties. Furthermore, TNBC exhibits a higher mutational burden and is acknowledged as the most immunogenic of all BC subtypes. Consequently, the application of immune checkpoint inhibition has been investigated in TNBC, yielding promising outcomes. Recent evidence identified extracellular vesicles (EVs) as an important contributor in the context of TNBC immunotherapy. In view of the extraordinary ability of EVs to transfer bioactive molecules, such as proteins, lipids, DNA, mRNAs, and small miRNAs, between the cells, EVs are considered a promising diagnostic biomarker and novel drug delivery system among the prospects for immunotherapy. The present review provides an in-depth understanding of how EVs influence TNBC progression, its immune regulation, and their contribution as a predictive biomarker for TNBC. The final part of the review focuses on the recent key advances in immunotherapeutic strategies for better understanding the complex interplay between EVs and the immune system in TNBC and further developing EV-based targeted immunotherapies.

Exosomes derived from rapamycin-treated 4T1 breast cancer cells induced polarization of macrophages to M1 phenotype

M2 macrophages are the most prevalent type in the tumor microenvironment and their polarization to M1 type can be used as a potential cancer immunotherapy. Here, we investigated the role of tumor microenvironment and particularly purified exosomes in M2 to M1 macrophage polarization. Rapamycin treatment on triple-negative breast cancer cells (TNBC) was performed. Tumor cells-derived exosomes (called texosomes) were isolated and characterized using scanning electron microscopy, transmission electron microscopy, dynamic light scattering, high-performance liquid chromatography, Fourier transform infrared, and Western blot assays. M2 mouse peritoneal macrophages were treated with rapamycin or rapamycin-texosome. Then, M1/M2 phenotype-specific marker genes and proteins were measured to assess the degree of M2 to M1 polarization. Finally, nitric oxide (NO) production, phagocytosis, and efferocytosis assays were assessed to verify the functionality of the polarized macrophages. Purified rapamycin-texosomes significantly increased the expression of the M1 markers (Irf5, Nos2, and CD86) and decreased M2 markers (Arg, Ym1, and CD206). In addition, the levels of M1-specific cytokines tumor necrosis factor alpha and interleukin 1β (IL-1β) were increased, whereas the levels of M2 specific cytokines IL-10 and transforming growth factor beta were declined. Furthermore, texosome treatment increased NO concentration and phagocytosis and decreased efferocytosis indicating M1 polarization. These findings suggest rapamycin-texosomes can induce M2 to M1 macrophages polarization as a potential immunotherapy for TNBC.

Harnessing actinobacteria potential for cancer prevention and treatment

Actinobacteria are gram-positive bacteria with high G:C ratio in their genetic makeup. They have been noted and studied for their capacity to produce bioactive substances with a range of uses in human health, and they also exhibit a unique property of adapting to extreme environments quite well. Actinobacteria may play an essential role in cancer prevention and treatment due to their synthesis of anticancer compounds, as indicated by recent studies. The aim of this review is to give a summary of what is currently known about the connection between actinobacteria and different types of cancer. This paper delineates the diverse array of actinobacterial bioactive compounds possessing anticancer properties, elucidates their mechanisms of action and explores potential applications in cancer treatment. Furthermore, this review highlights how the microbiome influences the onset and progression of cancer, as well as the discussing the potential benefits that actinobacteria may bring in terms of controlling the microbiome and contributing to the regulation of the tumour microenvironment to cure or prevent cancer.

Integrative analysis of mRNA and miRNA expression profiles and somatic variants in oxysterol signaling in early-stage luminal breast cancer

Oxysterols, oxidized derivatives of cholesterol, act in breast cancer (BC) as selective estrogen receptor modulators and affect cholesterol homeostasis, drug transport, nuclear and cell receptors, and other signaling proteins. Using data from three highly overlapping sets of patients (N = 162 in total) with early-stage estrogen-receptor-positive luminal BC-high-coverage targeted DNA sequencing (113 genes), mRNA sequencing, and full micro-RNA (miRNA) transcriptome microarrays-we describe complex oxysterol-related interaction (correlation) networks, with validation in public datasets (n = 538) and 11 databases. The ESR1-CH25H-INSIG1-ABCA9 axis was the most prominent, interconnected through miR-125b-5p, miR-99a-5p, miR-100-5p, miR-143-3p, miR-199b-5p, miR-376a-3p, and miR-376c-3p. Mutations in SC5D, CYP46A1, and its functionally linked gene set were associated with multiple differentially expressed oxysterol-related genes. STARD5 was upregulated in patients with positive lymph node status. High expression of hsa-miR-19b-3p was weakly associated with poor survival. This is the first study of oxysterol-related genes in BC that combines DNA, mRNA, and miRNA multiomics with detailed clinical data. Future studies should provide links between intratumoral oxysterol signaling depicted here, circulating oxysterol levels, and therapy outcomes, enabling eventual clinical exploitation of present findings.

Breast Cancer: Clinical-Epidemiological Profile and Toxicities of Women Receiving Treatment with Taxanes in the Amazon Region

Breast cancer is the most common malignant disease and the leading cause of mortality among women worldwide. Antineoplastic chemotherapy is one of its primary treatments, typically based on the class of drugs known as taxanes. Despite their proven therapeutic efficacy, these drugs can induce severe toxicities, leading to dose limitations or even treatment discontinuation. The objective of this study was to describe the clinical-epidemiological profile, risk factors, and toxicities of taxane-based chemotherapy treatment in women with breast cancer in the Amazon region. This is a cross-sectional, quantitative, and descriptive study conducted with 300 women diagnosed with breast cancer undergoing taxane treatment. Most patients were in the 40-49 age range, of brown ethnicity, and had completed elementary school. The majority of patients had risk factors such as alcoholism and a sedentary lifestyles. Most women had their first pregnancy between the ages of 18 and 21, breastfed their children, had menarche between the ages of 12 and 13, and were pre-menopausal and with a family history of cancer. The most frequent histological type was non-special invasive carcinoma and the Luminal B subtype. Most participants in this study showed taxane toxicity, with neurotoxicity being the most frequent. These findings reveal the importance of early detection, comprehensive risk factors, and effective management of treatment toxicities to improve patient outcomes in breast cancer care in the Amazon region.

Neratinib as adjuvant therapy in patients with HER2 positive breast cancer: expert opinion

Neratinib is a tyrosine kinase receptor inhibitor used in the extended adjuvant therapy of early-stage breast cancer. After adjuvant trastuzumab therapy, neratinib reduces the risk of recurrence and, if taken within 1 year from trastuzumab, significantly improves the invasive disease-free survival of patients with early-stage human epidermal growth factor receptor-2 positive (HER2+) breast cancer with no increased risk of long-term toxicity. Diarrhea, the most common adverse event associated with neratinib use, deters some clinicians from prescribing this drug. However, neratinib-related toxicity is predictable, short-lived, mostly limited to the first month of treatment and can be managed with dose-escalation and prophylactic strategies. Thus, close surveillance and prompt management, relying on supportive care and administration schedule modification, allows discontinuation of treatment to be avoided.

Let-7a/cMyc/CCAT1/miR-17-5p Circuit Re-sensitizes Atezolizumab Resistance in Triple Negative Breast Cancer through Modulating PD-L1

BACKGROUND

Triple negative breast cancer (TNBC) is an immunogenically hot tumor. The immune checkpoint blockades (ICBs) have been recently emerged as promising therapeutic candidates for several malignancies including TNBC. Yet, the development of innate and/or adaptive resistance by TNBC patients towards ICBs such as programmed death-ligand 1 (PD-L1) inhibitors (e.g. Atezolizumab) shed the light on importance of identifying the underlying mechanisms regulating PD-L1 in TNBC. Recently, it was reported that non-coding RNAs (ncRNAs) perform a fundamental role in regulating PD-L1 expression in TNBC. Hence, this study aims to explore a novel ncRNA axis tuning PD-L1 in TNBC patients and investigate its possible involvement in fighting Atezolizumab resistance.

METHODS

In-silico screening was executed to identify ncRNAs that could potentially target PD-L1. Screening of PD-L1 and the nominated ncRNAs (miR-17-5p, let-7a and CCAT1 lncRNA) was performed in BC patients and cell lines. Ectopic expression and/or knockdown of respective ncRNAs were performed in MDA-MB-231. Cellular viability, migration and clonogenic capacities were evaluated using MTT, scratch assay and colony-forming assay, respectively.

RESULTS

PD-L1 was upregulated in BC patients, especially in TNBC patients. PD-L1 is positively associated with lymph node metastasis and high Ki-67 in recruited BC patients. Let-7a and miR-17-5p were nominated as potential regulators of PD-L1. Ectopic expression of let-7a and miR-17-5p caused a noticeable reduction in PD-L1 levels in TNBC cells. In order to investigate the whole ceRNA circuit regulating PD-L1 in TNBC, intensive bioinformatic studies were performed. The lncRNA, Colon Cancer-associated transcript 1 (CCAT1), was reported to target PD-L1 regulating miRNAs. Results showed that CCAT1 is an upregulated oncogenic lncRNA in TNBC patients and cell lines. CCAT1 siRNAs induced a noticeable reduction in PD-L1 levels and a marked increase in miR-17-5p level, building up a novel regulatory axis CCAT1/miR-17-5p/PD-L1 in TNBC cells that was tuned by the let-7a/c-Myc engine. On the functional level, co-treatment of CCAT-1 siRNAs and let-7a mimics efficiently relieved Atezolizumab resistance in MDA-MB-231 cells.

CONCLUSION

The present study revealed a novel PD-L1 regulatory axis via targeting let-7a/c-Myc/CCAT/miR-17-5p. Additionally, it sheds the light on the potential combinational role of CCAT-1 siRNAs and Let-7a mimics in relieving Atezolizumab resistance in TNBC patients.

Breast Cancer Recurrence by Subtype in a Diverse, Contemporary Cohort of Young Women

BACKGROUND

Young breast cancer (YBC) patients are a unique subpopulation that are often underrepresented in randomized clinical trials. Furthermore, large national cancer databases lack detailed information on recurrence, a meaningful oncologic outcome for young patients.

STUDY DESIGN

A retrospective review of YBC patients (age 40 years or younger) with stage I to III breast cancer diagnosed from 2008 to 2018 was performed. Information on clinicopathologic characteristics, demographics, and outcomes was obtained from the electronic health record and chart review. Chi-square and Fisher's exact tests were used for comparisons of categorical variables and parametric and nonparametric tests for continuous variables.

RESULTS

The cohort included 1,431 women with a median follow-up of 4.8 years (range 0.3 to 12.9 years). The median age was 37 years (interquartile range 34 to 39). The study population included 598 (41.8%) White, 112 (7.8%) Black, 420 (29.4%) Asian/Pacific Islander, 281 (19.6%) Hispanic, and 20 (1.4%) "other" race/ethnicity patients. Tumor subtype was as follows: [1] hormone receptor (HR) + /human epidermal growth factor 2 (HER2 - ), grade (G) 1 to 2 = 541 (37.8%); [2] HR + /HER2 - , G3 = 268 (18.7%); [3] HR + /HER2 + = 262 (18.3%); [4] HR - /HER2 + = 101 (7.1%); [5] HR - /HER2 - = 259 (18.1%). The majority (64.2%) presented with stage II/III disease. There were 230 (16.1%) recurrences during follow-up; 74.8% were distant. Locoregional-only recurrence was seen in 17 of 463 (3.7%) patients who underwent breast conservation vs 41 of 968 (4.2%) patients undergoing mastectomy (p < 0.001). Recurrence varied by tumor subtype: [1] HR + /HER2 - , G1 to 2 (14.0%); [2] HR + /HER2 - , G3 (20.9%); [3] HR + /HER2 + (11.1%); [4] HR - /HER2 + (22.8%); [5] HR - /HER2 - (17.8%) (p = 0.005).

CONCLUSIONS

In this large, diverse YBC cohort, recurrences were most frequent among HR + /HER2 - , G3, or HR - /HER2 + invasive tumors; most were distant. There were numerically similar locoregional-only recurrences after breast conservation vs mastectomy. Additional research is needed to identify predictors of recurrence.

Breast cancer: the first comparative evaluation of oncobiome composition between males and females

BACKGROUND

Emerging evidence suggests that breast microbiota dysbiosis contributes to cancer initiation, progression, prognosis and treatment efficacy. Anyway, available data are referred only to female patients, and studies on males are completely missing. Male breast cancer (MBC) is 70-100 times less frequent, but the mortality rate adjusted to incidence is higher in men than in females. Currently, MBC diagnostic approaches and treatments have generally been extrapolated from the clinical experience gained in women, while few studies focus on characterizing male cancer biology. Taking into account the rising importance of the oncobiome field and the need of MBC targeted studies, we explored the breast cancer oncobiome of male and female patients.

METHODS

16S rRNA gene sequencing was performed in 20 tumor and 20 non-pathological adjacent FFPE breast tissues from male and female patients.

RESULTS

We documented, for the first time, the presence of a sexually dimorphic breast-associated microbiota, here defined as "breast microgenderome". Moreover, the paired analysis of tumor and non-pathological adjacent tissues suggests the presence of a cancer-associated dysbiosis in male patients, with surrounding tissue conserving a healthier microbiome, whereas in female patients, the entire breast tissue is predisposed to cancer development. Finally, the phylum Tenericutes, especially the genera Mesoplasma and Mycobacterium, could to be involved in breast carcinogenesis, in both sexes, deserving further investigation, not only for its role in cancer development but even as potential prognostic biomarker.

CONCLUSIONS

Breast microbiota characterization can enhance the understanding of male breast cancer pathogenesis, being useful for detection of new prognostic biomarkers and development of innovative personalized therapies, remarking the relevant gender differences.

The inhibition of steroid hormones determines the fate of IPC-366 tumor cells, highlighting the crucial role of androgen production in tumor processes

Inflammatory mammary cancer (IMC) is a disease that affects female dogs. It is characterized by poor treatment options and no efficient targets. However, anti-androgenic and anti-estrogenic therapies could be effective because IMC has a great endocrine influence, affecting tumor progression. IPC-366 is a triple negative IMC cell line that has been postulated as a useful model to study this disease. Therefore, the aim of this study was to inhibit steroid hormones production at different points of the steroid pathway in order to determine its effect in cell viability and migration in vitro and tumor growth in vivo. For this purpose, Dutasteride (anti-5αReductase), Anastrozole (anti-aromatase) and ASP9521 (anti-17βHSD) and their combinations have been used. Results revealed that this cell line is positive to estrogen receptor β (ERβ) and androgen receptor (AR) and endocrine therapies reduce cell viability. Our results enforced the hypothesis that estrogens promote cell viability and migration in vitro due to the function of E1SO4 as an estrogen reservoir for E2 production that promotes the IMC cells proliferation. Also, an increase in androgen secretion was associated with a reduction in cell viability. Finally, in vivo assays showed large tumor reduction. Hormone assays determined that high estrogen levels and the reduction of androgen levels promote tumor growth in Balb/SCID IMC mice. In conclusion, estrogen levels reduction may be associated with a good prognosis. Also, activation of AR by increasing androgen production could result in effective therapy for IMC because their anti-proliferative effect.

Impact of Atypical Hyperplasia at Surgical Margins on breast cancer outcomes in patients treated with neoadjuvant chemotherapy

Background

Women with atypical hyperplasia (AH) is associated with a higher risk of future breast cancer. However, whether AH found at margins in patients with breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NAC) needs re-excision is not well-defined. The aim of the present study was to evaluate the impact of AH at the surgical margins on the local recurrence and survival outcomes in breast cancer patients treated with NAC and BCS.

Methods

A retrospective analysis comparing patients who treated with NAC and BCS with AH at the margins to those without AH was performed.

Results

598 patients were included in this study. The 5-year rates of ipsilateral breast tumor recurrence (IBTR) were 4.6% and 6.2% in patients with and without AH, respectively. No significant differences were observed among the two groups in terms of IBTR, DMFS, or OS. HER2 overexpressing breast cancer patients with severe AH at margins have a significantly higher risk of IBTR compared to those without severe AH.

Conclusion

Our study suggests that the presence of AH at the surgical margins of BCS in patients who received NAC does not appear to increase the risk of ipsilateral breast cancer. Therefore, there is no need for surgeons to routinely perform additional re-excision of AH found at the margins of BCS in these patients. However, selective re-excision should be considered in certain cases, particularly in patients with HER2 overexpression.

Extracellular vesicles secreted by triple-negative breast cancer stem cells trigger premetastatic niche remodeling and metastatic growth in the lungs

Tumor secreted extracellular vesicles (EVs) are potent intercellular signaling platforms. They are responsible for the accommodation of the premetastatic niche (PMN) to support cancer cell engraftment and metastatic growth. However, complex cancer cell composition within the tumor increases also the heterogeneity among cancer secreted EVs subsets, a functional diversity that has been poorly explored. This phenomenon is particularly relevant in highly plastic and heterogenous triple-negative breast cancer (TNBC), in which a significant representation of malignant cancer stem cells (CSCs) is displayed. Herein, we selectively isolated and characterized EVs from CSC or differentiated cancer cells (DCC; EVs^CSC and EVs^DCC , respectively) from the MDA-MB-231 TNBC cell line. Our results showed that EVs^CSC and EVs^DCC contain distinct bioactive cargos and therefore elicit a differential effect on stromal cells in the TME. Specifically, EVs^DCC activated secretory cancer associated fibroblasts (CAFs), triggering IL-6/IL-8 signaling and sustaining CSC phenotype maintenance. Complementarily, EVs^CSC promoted the activation of α-SMA+ myofibroblastic CAFs subpopulations and increased the endothelial remodeling, enhancing the invasive potential of TNBC cells in vitro and in vivo. In addition, solely the EVs^CSC mediated signaling prompted the transformation of healthy lungs into receptive niches able to support metastatic growth of breast cancer cells.

Intraoperative sentinel node biopsy, is it worth the wait?

INTRODUCTION

In our institution, the study of selective sentinel node biopsy (SLNB) is performed intraoperatively. The main objective of our study is to know the proportion of patients who benefits from the waiting of the results of SLNB.

METHODS

A retrospective analysis of patients operated on our center between January 1st, 2018 and June 30, 2019 was carried out. We included women diagnosed with T1-T2 tumors, treated by lumpectomy and SLNB studied using OSNA method.

RESULTS

Our study included 149 women. There were not statistically significant differences in terms of demographic data between the group treated with axillary lymph node dissection (ALND) and exclusively SLNB group. After analysis of SLN intraoperatively, there were performed 18 axillary lymphadenectomies. Only in six of this 18 cases, three or more sentinel nodes were founded. The location of the tumor, the presence of lymphovascular permeation and the total tumor load (TTL) showed statistically significant differences between groups. Only the TTL was established as the independent factor of the need for ALND.

DISCUSSION

Obtaining a deferred result of the SLNB allowed reducing the time of anesthesia and occupation of the operating room, since in a high percentage of cases an additional procedure is not performed.

Hypercoagulability State Combined with Post-Treatment Hypofibrinolysis in Invasive Breast Cancer: A Seven-Year Follow-Up Evaluating Disease-Free and Overall Survival

(1) Background: Cancer treatment, including chemotherapy, endocrine therapy, targeted therapy and radiotherapy, has been identified as an important independent risk factor for venous thromboembolism in cancer patients. The aim of the study was to evaluate the effect of adjuvant therapy on the coagulation and fibrinolysis components in invasive breast cancer. (2) Methods: Tissue factor pathway inhibitor (TFPI), tissue factor (TF), tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) antigen (concentration) and TFPI and TF activities were examined in the blood samples of 60 breast cancer patients treated by adjuvant chemotherapy, endocrine therapy, radiotherapy and immunotherapy. Blood samples were taken 24 h before primary surgery and 8 months after tumour removal surgery. (3) Results: Adjuvant therapy administrated to breast cancer patients significantly increased the concentration of plasma TF, the PAI-1 antigen and also the activity of TFPI and TF, but significantly decreased the level of the t-PA antigen. Combined chemotherapy and endocrine therapy, but not monotherapy, has an important effect on haemostatic biomarker levels. (4) Conclusions: Breast cancer patients receiving adjuvant therapy have an elevated risk of developing a hypercoagulability and hypofibrinolysis state leading to venous thromboembolism.

Dual functionality of pyrimidine and flavone in targeting genomic variants of EGFR and ER receptors to influence the differential survival rates in breast cancer patients

Breast cancer ranks as one of the most prevalent forms of cancer and stands as the primary global cause of mortality among women. Overexpression of EGFR and ER receptors or their genomic alterations leads to malignant transformation, disease aggression and is linked to poor patient survival outcomes. The clinical breast cancer patient's genomic expression, survival analysis, and computational drug-targeting approaches were used to identify best-hit phytochemicals for therapeutic purposes. Breast cancer patients have genomic alterations in EGFR (4%, n = 5699) and ER (9%, n = 8461), with the highest proportion being missense mutations. No statistically significant difference was observed in the patient survival rates between the altered and unaltered ER groups, unlike EGFR, with the lowest survival rates in the altered group. Computational screening of natural compound libraries (7711) against each EGFR (3POZ) and ER (3ERT) receptor shortlists the best-hit 3 compounds with minimum docking score (ΔG = -7.9 to -10.8), MMGBSA (-40.16 to -51.91 kcal/mol), strong intermolecular H-bonding, drug-like properties with least kd, and ki. MD simulation studies display stable RMSD, RMSF, and good residual correlation of best-hit common compounds (PubChem ID: 5281672 and 5280863) targeting both EGFR and ER receptors. In vitro, studies revealed that these common drugs exhibited a high anti-proliferative effect on MCF-7 and MDA-MB-231 breast cancer cells, with effective IC50 values (15-40 μM) and lower free energy, kd, and ki (5281672 > 5280863 > 5330286) much affecting HEK-293 non-cancerous cells, indicating the safety profile. The experimental and computational correlation studies suggest that the highly expressed EGFR and ER receptors in breast cancer patients having poor survival rates can be effectively targeted with best-hit common potent drugs with a multi-target therapeutic approach. Insight Box: The findings of this study provide valuable insights into the genomic/proteomic data, breast cancer patient's survival analysis, and EGFR and ER receptor variants structural analysis. The genetic alterations analysis of EGFR and ER/ESR1 in breast cancer patients reveals the high frequency of mutation types, which affect patient's survival rate and targeted therapies. The common best-hit compounds affect the cell survival patterns with effective IC50, drug-like properties having lower equilibrium and dissociation constants demonstrating the anti-proliferative effects. This work integrates altered receptor structural analysis, molecular interaction-based simulations, and ADMET properties to illuminate the identified best hits phytochemicals potential efficacy targeting both EGFR and ER receptors, demonstrating a multi-target therapeutic approach.

Molecular Subtyping and Survival Analysis of Osteosarcoma Reveals Prognostic Biomarkers and Key Canonical Pathways

Osteosarcoma (OS) is a common bone malignancy in children and adolescents. Although histological subtyping followed by improved OS treatment regimens have helped achieve favorable outcomes, a lack of understanding of the molecular subtypes remains a challenge to characterize its genetic heterogeneity and subsequently to identify diagnostic and prognostic biomarkers for developing effective treatments. In the present study, global analysis of DNA methylation, and mRNA and miRNA gene expression in OS patient samples were correlated with their clinical characteristics. The mucin family of genes, MUC6, MUC12, and MUC4, were found to be highly mutated in the OS patients. Results revealed the enrichment of molecular pathways including Wnt signaling, Calcium signaling, and PI3K-Akt signaling in the OS tumors. Survival analyses showed that the expression levels of several genes such as RAMP1, CRIP1, CORT, CHST13, and DDX60L, miRNAs and lncRNAs were associated with survival of OS patients. Molecular subtyping using Cluster-Of-Clusters Analysis (COCA) for mRNA, lncRNA, and miRNA expression; DNA methylation; and mutation data from the TARGET dataset revealed two distinct molecular subtypes, each with a distinctive gene expression profile. Between the two subtypes, three upregulated genes, POP4, HEY1, CERKL, and seven downregulated genes, CEACAM1, ABLIM1, LTBP2, ISLR, LRRC32, PTPRF, and GPX3, associated with OS metastasis were found to be differentially regulated. Thus, the molecular subtyping results provide a strong basis for classification of OS patients that could be used to develop better prognostic treatment strategies.

Investigating unique genes of five molecular subtypes of breast cancer using penalized logistic regression

Background

Breast cancer (BC) is the most common cancer and the fifth cause of death in women worldwide. Exploring unique genes for cancers has been interesting.

Patients and Methods

This study aimed to explore unique genes of five molecular subtypes of BC in women using penalized logistic regression models. For this purpose, microarray data of five independent GEO data sets were combined. This combination includes genetic information of 324 women with BC and 12 healthy women. Least absolute shrinkage and selection operator (LASSO) logistic regression and adaptive LASSO logistic regression were used to extract unique genes. The biological process of extracted genes was evaluated in an open-source GOnet web application. R software version 3.6.0 with the glmnet package was used for fitting the models.

Results

Totally, 119 genes were extracted among 15 pairwise comparisons. Seventeen genes (14%) showed overlap between comparative groups. According to GO enrichment analysis, the biological process of extracted genes was enriched in negative and positive regulation biological processes, and molecular function tracking revealed that most genes are involved in kinase and transferring activities. On the other hand, we identified unique genes for each comparative group and the subsequent pathways for them. However, a significant pathway was not identified for genes in normal-like versus ERBB2 and luminal A, basal versus control, and lumina B versus luminal A groups.

Conclusion

Most genes selected by LASSO logistic regression and adaptive LASSO logistic regression identified unique genes and related pathways for comparative subgroups of BC, which would be useful to comprehend the molecular differences between subgroups that would be considered for further research and therapeutic approaches in the future.

Identifying potential ligand molecules EGFR mediated TNBC targeting the kinase domain-identification of customized drugs through in silico methods

Background and Purpose

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer in which three hormone receptors are negative. This work aimed at identifying customized potential molecules inhibiting epidermal growth factor receptor (EGFR) by exploring variants using the pharmacogenomics approaches.

Experimental approach

The pharmacogenomics approach has been followed to identify the genetic variants across the 1000 genomes continental population. Model proteins for the populations have been designed by including genetic variants in the reported positions. The 3D structures of the mutated proteins have been generated through homology modeling. The kinase domain present in the parent and the model protein molecules has been investigated. The docking study has been performed with the protein molecules against the kinase inhibitors evaluated by the molecular dynamic simulation studies. Molecular evolution has been performed to generate the potential derivatives of these kinase inhibitors suitable for the conserved region of the kinase domain. This study considered variants within the kinase domain as the sensitive region and remaining residues as the conserved region.

Findings/Results

The results reveal that few kinase inhibitors interact with the sensitive region. Among the derivatives of these kinase inhibitors molecules, the potential kinase inhibitor that interacts with the different population models has been identified.

Conclusions and implications

This study encompasses the importance of genetic variants in drug action as well as in the design of customized drugs. This research gives way to designing customized potential molecules inhibiting EGFR by exploring variants using the pharmacogenomics approaches.

A recombinant adenovirus vector containing the synNotch receptor gene for the treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is known as the most difficult molecular subtype of breast cancer to treat. Recent studies revealed that cancer stem cells (CSCs) play a critical role in TNBC recurrence and metastasis. In this study, we developed a recombinant replication-deficient adenoviral vector (Ad-CD44-N-HIF-3α4), which contains a gene encoding a synthetic Notch (synNotch) receptor composed of the extracellular domain of CD44 (CD44-ECD) and the hypoxia-inducible factor (HIF)-3α4 connected by the Notch core regulatory region. CD44 is a transmembrane glycoprotein and known as a CSC marker in breast cancer and other malignancies. HIF-3α4 is a dominant-negative regulator of HIF-1α and HIF-2α and inhibits hypoxia-inducing effect. Both CD44 and HIF signals contribute cancer stemness and maintaining CSCs in breast cancer. The CD44-ECD in the synNotch receptor acts as the CD44 decoy receptor, and after a ligand such as a hyaluronic acid binds to the CD44-ECD, HIF-3α4 is released from the Notch core domain. We performed an in vivo study using a mouse xenograft model of MDA-MB-231, a highly invasive TNBC cell, and confirmed the significant antitumor activity of the intratumoral injections of Ad-CD44-N-HIF3α4. Our findings in this study warrant the further development of Ad-CD44-N-HIF3α4 for the treatment of patients with TNBC.

Targeting Mitochondria with ClpP Agonists as a Novel Therapeutic Opportunity in Breast Cancer

Breast cancer is the most frequently diagnosed malignancy worldwide and the leading cause of cancer mortality in women. Despite the recent development of new therapeutics including targeted therapies and immunotherapy, triple-negative breast cancer remains an aggressive form of breast cancer, and thus improved treatments are needed. In recent decades, it has become increasingly clear that breast cancers harbor metabolic plasticity that is controlled by mitochondria. A myriad of studies provide evidence that mitochondria are essential to breast cancer progression. Mitochondria in breast cancers are widely reprogrammed to enhance energy production and biosynthesis of macromolecules required for tumor growth. In this review, we will discuss the current understanding of mitochondrial roles in breast cancers and elucidate why mitochondria are a rational therapeutic target. We will then outline the status of the use of mitochondria-targeting drugs in breast cancers, and highlight ClpP agonists as emerging mitochondria-targeting drugs with a unique mechanism of action. We also illustrate possible drug combination strategies and challenges in the future breast cancer clinic.

Defining the Emergence of New Immunotherapy Approaches in Breast Cancer: Role of Myeloid-Derived Suppressor Cells

Breast cancer (BC) continues to be the most diagnosed tumor in women and a very heterogeneous disease both inter- and intratumoral, mainly given by the variety of molecular profiles with different biological and clinical characteristics. Despite the advancements in early detection and therapeutic strategies, the survival rate is low in patients who develop metastatic disease. Therefore, it is mandatory to explore new approaches to achieve better responses. In this regard, immunotherapy arose as a promising alternative to conventional treatments due to its ability to modulate the immune system, which may play a dual role in this disease since the relationship between the immune system and BC cells depends on several factors: the tumor histology and size, as well as the involvement of lymph nodes, immune cells, and molecules that are part of the tumor microenvironment. Particularly, myeloid-derived suppressor cell (MDSC) expansion is one of the major immunosuppressive mechanisms used by breast tumors since it has been associated with worse clinical stage, metastatic burden, and poor efficacy of immunotherapies. This review focuses on the new immunotherapies in BC in the last five years. Additionally, the role of MDSC as a therapeutic target in breast cancer will be described.

Coumarin derivative as a potent drug candidate against triple negative breast cancer targeting the frizzled receptor of wingless-related integration site signaling pathway

Triple negative breast cancer constitutes to about 21.8 percent of the total breast cancer related cases. Its ability to affect young ladies and in pre-menstrual stage makes this a disease of concern worldwide. The current treatment regimens involve chemotherapy which are used for treatment of other cancer types. In this regard, there is a need for specific and targeted drug candidate for its effective treatment. In the current study, assessment of coumarin derivative 2-(2-(6- Methyl-2-Oxo-2H-chromen-4-yl) acetamido)-3-phenylpropanoic acid is carried out both In-silico and In-vitro methods. Frizzled transmembrane proteins of Wingless-related integration site signaling pathway was targeted in which Frizzled-7 proved to a prospective target and showed a binding energy of -6.78 kcal/mol. The complex was subjected to molecular dynamics simulation for 200 ns and showed stable interaction with cysteine rich domain of the receptor. Cell proliferation, viability and apoptosis assay were performed on MDA-MB-231 and MDA-MB-468 cell lines with an IC₅₀ value of 81.23 and 84.68 µM, respectively. The results provide a drug candidate which is derivative of a natural compound with targeted TNBC inhibitory effect. Communicated by Ramaswamy H. Sarma.

Breast Amide Proton Transfer Imaging at 3 T: Diagnostic Performance and Association With Pathologic Characteristics

BACKGROUND

Amide proton transfer (APT) imaging has been increasingly applied in tumor characterization. However, its value in evaluating breast cancer remains undetermined.

PURPOSE

To assess the diagnostic performance of APT imaging in breast cancer and its association with prognostic histopathologic characteristics.

STUDY TYPE

Prospective.

SUBJECTS

Eighty-four patients with breast lesions.

FIELD STRENGTH/SEQUENCE

A 3.0 T/single-shot fast spin echo APT imaging.

ASSESSMENT

APTw signal in breast lesion was quantified. Lesion malignancy, T stage, grades, Ki-67 index, molecular biomarkers (estrogen receptor [ER] expression, progesterone receptor [PR] expression, human epidermal growth factor receptor [HER-2] expression), molecular subtypes (luminal A, luminal B, triple negative, and HER-2 enriched) were determined.

STATISTICAL TESTS

Student t-test, one-way analysis of variance, receiver operating characteristic analysis, and Pearson's correlation with P < 0.05 as statistical significance.

RESULTS

APTw signal was significantly higher in malignant lesions (1.55% ± 1.24%) than in benign lesions (0.54% ± 1.13%), and in grade III lesions than in grade II lesions (1.65% ± 0.84% vs. 0.96% ± 0.96%), and in T2- (1.57% ± 0.64%) and T3-stage lesions (1.54% ± 0.63%) than in T1-stage lesions (0.81% ± 0.64%) for invasive breast carcinoma of no special type. APTw signal significantly correlated with Ki-67 index (r = 0.364) but showed no significant difference in groups of ER (P = 0.069), PR (P = 0.069), HER-2 (P = 0.961), and among molecular subtypes (P = 0.073).

DATA CONCLUSION

APT imaging shows potential in differentiating breast lesion malignancy and associates with prognosis-related tumor grade, T stage, and proliferative activity.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 2.

Circular RNAs: New layer of complexity evading breast cancer heterogeneity

Advances in high-throughput sequencing techniques and bioinformatic analysis have refuted the "junk" RNA hypothesis that was claimed against non-coding RNAs (ncRNAs). Circular RNAs (circRNAs); a class of single-stranded covalently closed loop RNA molecules have recently emerged as stable epigenetic regulators. Although the exact regulatory role of circRNAs is still to be clarified, it has been proven that circRNAs could exert their functions by interacting with other ncRNAs or proteins in their own physiologically authentic environment, regulating multiple cellular signaling pathways and other classes of ncRNAs. CircRNAs have also been reported to exhibit a tissue-specific expression and have been associated with the malignant transformation process of several hematological and solid malignancies. Along this line of reasoning, this review aims to highlight the importance of circRNAs in Breast Cancer (BC), which is ranked as the most prevalent malignancy among females. Notwithstanding the substantial efforts to develop a suitable anticancer therapeutic regimen against the heterogenous BC, inter- and intra-tumoral heterogeneity have resulted in an arduous challenge for drug development research, which in turn necessitates the investigation of other markers to be therapeutically targeted. Herein, the potential of circRNAs as possible diagnostic and prognostic biomarkers have been highlighted together with their possible application as novel therapeutic targets.

Effects of siRNA-mediated Silencing of ERBB2, IGF-1R, and ITGB1 in HER2-positive Breast Cancer Cells

BACKGROUND/AIM

One of the hallmarks of cancer is deregulation of multiple signaling pathways, which can lead to uncontrolled proliferation and migration of cells. Over-expression and mutations in human epidermal growth factor receptor 2 (HER2) can lead to overactivation of these pathways, potentially developing cancer in different tissues, including breast tissue. IGF-1R and ITGB-1 are two receptors that have been linked to cancer development. Therefore, the aim of this study was to investigate the effects of silencing of the corresponding genes using specific siRNAs.

MATERIALS AND METHODS

Transient silencing of HER2, ITGB-1, and IGF-1R was conducted using siRNAs and expression was quantified by reverse transcription-quantitative polymerase chain reaction. Viability in human breast cancer cells SKBR3, MCF-7, and HCC1954 and cytotoxicity in HeLa cells were tested using WST-1 assay.

RESULTS

The use of anti-HER2 siRNAs in a breast cancer cell line over-expressing HER2 (SKBR3) led to a decrease in cell viability. However, silencing of ITGB-1 and IGF-1R in the same cell line had no significant effects. Silencing of any of the genes encoding any of the three receptors in MCF-7, HCC1954, and HeLa had no significant effects.

CONCLUSION

Our results provide evidence towards using siRNAs against HER2-positive breast cancer. Silencing of ITGB-1 and IGF-R1 did not significantly inhibit the growth of SKBR3 cells. Therefore, there is need for testing the effect of silencing ITGB-1 and IGF-R1 in other cancer cell lines over-expressing these biomarkers and explore their potential use in cancer therapy.

Ki 67: a Promising Prognostic Marker in Early Breast Cancer-a Review Article

Ki67 index is considered to be a reliable indicator of the proliferative activity of breast cancer. Additionally, the Ki67 proliferative marker may play a role in assessing response to systemic therapeutic strategies and can act as a prognostic biomarker. But its limited reproducibility which stems from a lack of standardization of procedures, inter-observer variability, and preanalytical and analytical variabilities all have hampered the use of the Ki67 index in clinical practice. Currently, clinical trials have been evaluating Ki67 as a predictive marker for needing adjuvant chemotherapy in luminal early breast cancer patients receiving neoadjuvant endocrine therapy. But the inconsistencies existing in the estimation of the Ki67 index limit the utility of Ki67 in standard clinical practice. The purpose of this review is to evaluate the benefits and drawbacks of utilizing Ki-67 in early-stage breast cancer to prognosticate the disease and predict the risk of recurrence.

NEDD9 Overexpression Causes Hyperproliferation of Luminal Cells and Cooperates with HER2 Oncogene in Tumor Initiation: A Novel Prognostic Marker in Breast Cancer

HER2 overexpression occurs in 10-20% of breast cancer patients. HER2+ tumors are characterized by an increase in Ki67, early relapse, and increased metastasis. Little is known about the factors influencing early stages of HER2- tumorigenesis and diagnostic markers. Previously, it was shown that the deletion of NEDD9 in mouse models of HER2 cancer interferes with tumor growth, but the role of NEDD9 upregulation is currently unexplored. We report that NEDD9 is overexpressed in a significant subset of HER2+ breast cancers and correlates with a limited response to anti-HER2 therapy. To investigate the mechanisms through which NEDD9 influences HER2-dependent tumorigenesis, we generated MMTV-Cre-NEDD9 transgenic mice. The analysis of mammary glands shows extensive ductal epithelium hyperplasia, increased branching, and terminal end bud expansion. The addition of oncogene Erbb2 (neu) leads to the earlier development of early hyperplastic benign lesions (~16 weeks), with a significantly shorter latency than the control mice. Similarly, NEDD9 upregulation in MCF10A-derived acini leads to hyperplasia-like DCIS. This phenotype is associated with activation of ERK1/2 and AURKA kinases, leading to an increased proliferation of luminal cells. These findings indicate that NEDD9 is setting permissive conditions for HER2-induced tumorigenesis, thus identifying this protein as a potential diagnostic marker for early detection.

Shining the light on mesenchymal stem cell-derived exosomes in breast cancer

In women, breast cancer (BC) is the second most frequently diagnosed cancer and the leading cause of cancer death. Mesenchymal stem cells (MSCs) are a subgroup of heterogeneous non-hematopoietic fibroblast-like cells that have the ability to differentiate into multiple cell types. Recent studies stated that MSCs can migrate into the tumor sites and exert various effect on tumor growth and development. Multiple researches have demonstrated that MSCs can favor tumor growth, while other groups have indicated that MSCs inhibit tumor development. Emerging evidences showed exosomes (Exo) as a new mechanism of cell communication which are essential for the crosstalk between MSCs and BC cells. MSC-derived Exo (MSCs-Exo) could mimic the numerous effects on the proliferation, metastasis, and drug response through carrying a wide scale of molecules, such as proteins, lipids, messenger RNAs, and microRNAs to BC cells. Consequently, in the present literature, we summarized the biogenesis and cargo of Exo and reviewed the role of MSCs-Exo in development of BC.

Reconceptualizing the clinicopathological features, locoregional therapy and prognostic factors of occult breast cancer in the era of molecular subtyping

To evaluate the clinical features, molecular subtypes, therapeutic strategies, and prognostic factors of occult breast cancer (OBC). Patients with T0-3/N1-3/M0 breast cancer diagnosed in 2010-2018 (n = 114,303, including 691 with OBC) were retrieved from the Surveillance, Epidemiology, and End-Results (SEER) database. The endpoints were overall survival (OS) and breast cancer-specific survival (BCSS). Compared with non-OBC, OBC presented significantly more adverse clinicopathological prognostic features. More patients with OBC underwent breast-conserving treatment (BCT) and less had axillary lymphadenectomy (ALD). Outcomes were more favorable in OBC cases compared with non-OBC cases (p = .002 for OS, p = .002 for BCSS). Triple-negative (TNBC) and HER2-enriched were the subtypes with the worst prognosis in OBC (p < .05). Prognosis was better for triple-negative OBC compared with the same subtype of non-OBC. N-stage was not a strong prognostic indicator of OBC (p > .05 for OS). Cases who underwent systemic chemotherapy alone without surgery had the worst prognosis among OBC patients. For locoregional therapy, mastectomy and radiotherapy could confer survival advantage; standard axillary lymph node dissection (ALND) and positive lymph node dissection (PLND) contributed notably to OS in OBC patients. Both OS and BCSS were better in OBC cases compared with non-OBC. Systemic chemotherapy alone without surgery is not appropriate for OBC treatment, and mastectomy plus standard axillary surgery is recommended. Patients with hormone receptor-positive and low burden of axillary lymph node metastasis may be spared from radiotherapy after undergoing standard axillary lymphadenectomy.

Profiles of Expression of SAV1 in Normoxia or Hypoxia Microenviroment are Associated with Breast Cancer Prognosis

BACKGROUND

In breast cancer (BC), hypoxia is associated with poor prognosis. Protein Salvador homolog 1 (SAV1) acts as a tumor suppressor and is downregulated in the cancer cells. However, there is limited data on the expression profile of SAV1 and its importance in BC. It has not been studied to evaluate this phenomenon in a hypoxic microenvironment yet.

AIM

This study aimed to investigate SAV1 expression profiles under normoxia and hypoxia, and the potential of SAV1 in BC prognosis.

METHODS

Gene and protein expression analyses were performed using Real-Time quantitative PCR (RT-qPCR) and immunocytochemistry (ICC), respectively, and in silico analyses were performed using The Cancer Genome Atlas (TCGA). The survival curves were constructed using KMplotter.

RESULTS

SAV1 expression was lower in BC samples and tumor cell lines than in normal samples. The SAV1 mRNA levels were reduced in hypoxic estrogen receptor positive (ER⁺) tumors, which were associated with a lower survival probability as compared to normoxic ER⁺ tumors. Furthermore, lower levels of SAV1 were found in advanced cancer stage samples, which are associated with worse survival curves and can be a risk factor for BC.

CONCLUSIONS

These data suggest a potential prognostic role of SAV1 in BC, with lower expressions associated with worse prognosis.

Relationship between pathological response and molecular subtypes in locally advanced breast cancer patients receiving neoadjuvant chemotherapy

Majority of patients with breast cancer were diagnosed with locally advanced stages of the disease (54%). This study aimed to explain the pathological response received to neoadjuvant chemotherapy (NACT) according to the molecular classification of breast cancer in patients with locally advanced tumors. One hundred and one patients with locally advanced breast cancer treated with neoadjuvant chemotherapy were analyzed. Patients were classified into five molecular subtypes based on the profile of the estrogen receptor, progesterone receptor, HER2, and Ki-67. We determined associations between complete pathological response (no invasive tumor after neoadjuvant chemotherapy) and molecular subgroups. Most patients had luminal A tumors (n: 28, 27.7%). The overall rate of complete pathological response (pCR) was 34.7% (n:35). Tumors that presented with the highest rate of pCR were pure HER2-positive, at 60% (n:6; OR, 3.2; 95% CI, 0.8-12.2). According to logistic regression analysis, the factors affecting pCR were HER2 positivity and clinically positive axilla before NACT. Luminal A tumors had a significantly lower pCR rate. (7.1%,p: 0.001). Despite the low pCR rate, Luminal A tumor had the best survival rate in the subgroups (p < 0.001). However, there was no difference between EFS and OS according to pCR in any molecular subgroups. Pathological complete response is directly related to the subtypes of breast cancer. A high complete pathological response rate is observed in the pure HER2-positive group. However, EFS and OS were not statistically significant in patients with and without pCR.

Cytotoxic evaluation of YSL-109 in a triple negative breast cancer cell line and toxicological evaluations

Breast cancer (BC) is the leading cause of cancer-related death in women worldwide. Triple negative breast cancer (TNBC) is the most aggressive form of BC being with the worst prognosis and the worst survival rates. There is no specific pharmacological target for the treatment of TNBC; conventional therapy includes the use of non-specific chemotherapy that generally has a poor prognosis. Therefore, the search of effective therapies against to TNBC continues at both preclinical and clinical level. In this sense, the exploration of different pharmacological targets is a continue task that pave the way to epigenetic modulation using novel small molecules. Lately, the inhibition of histone deacetylases (HDACs) has been explored to treat different BC, including TNBC. HDACs remove the acetyl groups from the ɛ-amino lysine resides on histone and non-histone proteins. In particular, the inhibition of HDAC6 has been suggested to be useful for the treatment of TNBC due to it is overexpressed in TNBC. Therefore, in this work, an HDAC6 selective inhibitor, the (S)-4-butyl-N-(1-(hydroxyamino)-3-(naphthalen-1-yl)-1-oxopropan-2-yl) benzamide (YSL-109), was assayed on TNBC cell line (MDA-MB231) showing an antiproliferative activity (IC₅₀ = 50.34 ± 1.11 µM), whereas on fibroblast, it was lesser toxic. After corroborating the in vitro antiproliferative activity of YSL-109 in TNBC, the toxicological profile was explored using combined approach with in silico tools and experimental assays. YSL-109 shows moderate mutagenic activity on TA-98 strain at 30 and 100 µM in the Ames test, whereas YSL-109 did not show in vivo genotoxicity and its oral acute toxicity (LD₅₀) in CD-1 female mice was higher than 2000 mg/kg, which is in agreement with our in silico predictions. According to these results, YSL-109 represents an interesting compound to be explored for the treatment of TNBC under preclinical in vivo models.

Peripubertal Nutritional Prevention of Cancer-Associated Gene Expression and Phenotypes

Breast cancer (BC) is a nearly ubiquitous malignancy that effects the lives of millions worldwide. Recently, nutritional prevention of BC has received increased attention due to its efficacy and ease of application. Chief among chemopreventive compounds are plant-based substances known as dietary phytochemicals. Sulforaphane (SFN), an epigenetically active phytochemical found in cruciferous vegetables, has shown promise in BC prevention. In addition, observational studies suggest that the life stage of phytochemical consumption may influence its anticancer properties. These life stages, called critical periods (CPs), are associated with rapid development and increased susceptibility to cellular damage. Puberty, a CP in which female breast tissue undergoes proliferation and differentiation, is of particular interest for later-life BC development. However, little is known about the importance of nutritional chemoprevention to CPs. We sought to address this by utilizing two estrogen receptor-negative [ER(-)] transgenic mouse models fed SFN-containing broccoli sprout extract during the critical period of puberty. We found that this treatment resulted in a significant decrease in tumor incidence and weight, as well as an increase in tumor latency. Further, we found significant alterations in the long-term expression of cancer-associated genes, including p21, p53, and BRCA2. Additionally, our transcriptomic analyses identified expressional changes in many cancer-associated genes, and bisulfite sequencing revealed that the antiproliferation-associated gene Erich4 was both hypomethylated and overexpressed in our experimental group. Our study indicates that dietary interventions during the CP of puberty may be important for later-life ER(-) BC prevention and highlights potential important genetic and epigenetic targets for treatment and study of the more deadly variants of BC.

Patterns of regional recurrence according to molecular subtype in patients with pN2 breast cancer treated with limited field regional irradiation

OBJECTIVE

There is little evidence regarding the radiotherapy modification based on molecular subtypes in breast cancer. This study aimed to identify the risk and patterns of regional recurrence according to molecular subtype in patients with pN2 breast cancer.

METHODS

We identified 454 patients who underwent radical surgery for breast cancer with 4-9 axillary lymph node metastases. All patients underwent axillary lymph node dissection, adjuvant chemotherapy and limited-field regional nodal irradiation. The rates and patterns of regional recurrence were compared between the following three subgroups: luminal type (estrogen receptor- and/or progesterone receptor-positive), HER2-type (estrogen receptor- and progesterone receptor-negative and HER2-positive) and triple-negative type (estrogen receptor-, progesterone receptor- and HER2-negative).

RESULTS

Regional recurrence occurred in 18/454 patients (4%). The risk of regional recurrence was higher in the triple-negative (hazard ratio 7.641) and HER2-type (hazard ratio 4.032) subtypes than in the luminal subtype. The predominant pattern of regional recurrence was inside the radiotherapy field in triple-negative breast cancer and outside the radiotherapy field in HER2-type and luminal-type cancers.

CONCLUSIONS

In patients with pN2 breast cancer, the risk of regional recurrence was higher in the triple-negative and HER2-type than in the luminal type. In-field recurrence was predominant in triple-negative cancer, while out-field recurrence was frequent in luminal and HER2-type breast cancers.

DCE-MRI Radiomics Analysis in Differentiating Luminal A and Luminal B Breast Cancer Molecular Subtypes

RATIONALE AND OBJECTIVES

The aim of the present study was to investigate the association between Luminal A and Luminal B molecular subtypes and radiomic features of dynamic contrast‑enhanced magnetic resonance imaging in patients with invasive breast cancer.

MATERIALS AND METHODS

Seventy-three patients with histopathologically proven invasive ductal cancer (IDC) were selected. Tumors were classified into molecular subtypes: Luminal A (estrogen receptor (ER)-positive and/or progesterone receptor (PR)-positive, human epidermal growth factor receptor type 2 (HER2) -negative, proliferation marker Ki-67<20) and Luminal B (ER-positive and/or PR-positive, HER2-positive or HER2-negative with high Ki-67 ≥20). A total of 81 tumoral lesions were evaluated on T1-weighted fat-suppressed sagittal post-contrast late-phase MRI images after the required "pre-process" steps and 3D segmentations were made. Forty-three radiomic features including: 1 conventional, 4 shape, 6 histogram, 7 Grey-Level Co-occurrence Matrix (GLCM), 11 Grey-Level Run-Length Matrix (GLRLM), 3 Neighborhood Grey-Level Difference Matrix (NGLDM), 11 Grey-Level Zone-Length Matrix (GLZLM) were extracted by using the software LIFEX.

RESULTS

A statistically significant difference was found in radiomic features including; a) Histogram: "skewness", b) Shape: "volume-ml, volume-voxel," c) GLCM: "entropy.log10, entropy.log2, energy", d) GLRLM: "GLNU, RLNU, HGRE," e) NGLDM: "busyness," f) GLZLM: "GLNU, HGZE, ZLNU, SZE" between two different molecular subtypes. The model combining Shape-volume (ml) and GLZLM-HGZE yielded 0.746 area under the curve (AUC), 0.744 sensitivity, 0.643 specificity and 0.694 accuracy.

CONCLUSION

Radiomic properties that may distinguish Luminal A and Luminal B molecular subtypes of IDC were identified. The radiomic features were thought to reflect the intratumoral heterogeneity in molecular subtypes. This study demonstrated that the characterization of Luminal A and Luminal B tumors could be made non-invasively by radiomics analysis.