Gene expression profiling and histopathological characterization of triple-negative/basal-like breast carcinomas

Therapeutic vulnerabilities in triple negative breast cancer: Stem-like traits explored within molecular classification

Triple Negative Breast Cancer (TNBC) is the most aggressive type of breast cancer (BC). Despite advances in the clinical management of TNBC, recurrence-related mortality remains a challenge. The stem-like phenotype of TNBC plays a significant role in the persistence of minimal disease residue after therapy. Individuals exhibiting stem-like characteristics are particularly prone to inducing malignant relapse accompanied by strong resistance. Therefore, stem-like traits have been broadly proposed as therapeutic vulnerabilities to treat TNBC and reduce recurrence. However, heterogeneity within TNBC often generally restricts the stability of the therapeutic efficacy. To understand the heterogeneity and manage TNBC more precisely, multiple TNBC subtyping categories have been reported, providing the basis for profile-according therapeutic regimens. To provide more insight into targeting stem-like traits to ablate TNBC and reduce recurrence in the context of heterogeneity, this paper reviewed the molecular subtyping of TNBC, identified the consensus subtypes with distinct stem-like phenotypes, characterized the stemness hierarchy of TNBC, outlined the biological models for stem-like TNBC subtypes, summarized the therapeutic vulnerabilities in stem-like traits of the subtypes, and proposed potential therapeutic regimens targeting stem-like characteristics to improve TNBC prognosis.

Potential Perturbations of Critical Cancer-regulatory Genes in Triple-Negative Breast Cancer Cells Within the Humanized Microenvironment of Patient-derived Xenograft Models

PURPOSE

In this study, we aimed to establish humanized patient-derived xenograft (PDX) models for triple-negative breast cancer (TNBC) using cord blood (CB) hematopoietic stem cells (HSCs). Additionally, we attempted to characterize the immune microenvironment of the humanized PDX model to understand the potential implications of altered tumor-immune interactions in the humanized PDX model on the behavior of TNBC cells.

METHODS

To establish a humanized mouse model, high-purity CD34+ HSCs from CB were transplanted into immunodeficient NOD scid γ mice. Peripheral and intratumoral immune cell compositions of humanized and non-humanized mice were compared. Additionally, RNA sequencing of the tumor tissues was performed to characterize the gene expression features associated with humanization.

RESULTS

After transplanting the CD34+ HSCs, CD45+ human immune cells appeared within five weeks. A humanized mouse model showed viable human immune cells in the peripheral blood, lymphoid organs, and in the tumor microenvironment. Humanized TNBC PDX models showed varying rates of tumor growth compared to that of non-humanized mice. RNA sequencing of the tumor tissue showed significant alterations in tumor tissues from the humanized models. tumor necrosis factor receptor superfamily member 11B (TNFRSF11B) is a shared downregulated gene in tumor tissues from humanized models. Silencing of TNFRSF11B in TNBC cell lines significantly reduced cell proliferation, migration, and invasion in vitro. Additionally, TNFRSF11B silenced cells showed decreased tumorigenicity and metastatic capacity in vivo.

CONCLUSION

Humanized PDX models successfully recreated tumor-immune interactions in TNBC. TNFRSF11B, a commonly downregulated gene in humanized PDX models, may play a key role in tumor growth and metastasis. Differential tumor growth rates and gene expression patterns highlighted the complexities of the immune response in the tumor microenvironment of humanized PDX models.

The TGFβ2-Snail1-miRNATGFβ2 Circuitry is Critical for the Development of Aggressive Functions in Breast Cancer

There have been contradictory reports on the biological role of transforming growth factor-βs (TGFβs) in breast cancer (BC), especially with regard to their ability to promote epithelial-mesenchymal transition (EMT). Here, we show that TGFβ2 is preferentially expressed in mesenchymal-like BCs and maintains the EMT phenotype, correlating with cancer stem cell-like characteristics, growth, metastasis and chemo-resistance and predicting worse clinical outcomes. However, this is only true in ERα- BC. In ERα+ luminal-type BC, estrogen receptor interacts with p-Smads to block TGFβ signalling. Furthermore, we also identify a microRNAs (miRNAs) signature (miRNAsTGFβ2 ) that is weakened in TGFβ2-overexpressing BC cells. We discover that TGFβ2-Snail1 recruits enhancer of zeste homolog-2 to convert miRNAsTGFβ2 promoters from an active to repressive chromatin configuration and then repress miRNAsTGFβ2 transcription, forming a negative feedback loop. On the other hand, miRNAsTGFβ2 overexpression reverses the mesenchymal-like traits in agreement with the inhibition of TGFβ2-Snail1 signalling in BC cells. These findings clarify the roles of TGFβ2 in BC and suggest novel therapeutic strategies based on the TGFβ2-Snail1-miRNAsTGFβ2 loop for a subset type of human BCs.

IMPA2 promotes basal-like breast cancer aggressiveness by a MYC-mediated positive feedback loop

Basal-like breast cancer (BLBC) is the most aggressive subtype with poor prognosis; however, the mechanisms underlying aggressiveness in BLBC remain poorly understood. In this study, we showed that in contrast to other subtypes, inositol monophosphatase 2 (IMPA2) was dramatically increased in BLBC. Mechanistically, IMPA2 expression was upregulated due to copy number amplification, hypomethylation of IMPA2 promoter and MYC-mediated transcriptional activation. IMPA2 promoted MI-PI cycle and IP3 production, and IP3 then elevated intracellular Ca2+ concentration, leading to efficient activation of NFAT1. In turn, NFAT1 up-regulated MYC expression, thereby fulfilling a positive feedback loop that enhanced aggressiveness of BLBC cells. Knockdown of IMPA2 expression caused the inhibition of tumorigenicity and metastasis of BLBC cells in vitro and in vivo. Clinically, high IMPA2 expression was strongly correlated with large tumor size, high grade, metastasis and poor survival, indicating poor prognosis in breast cancer patients. These findings suggest that IMPA2-mediated MI-PI cycle allows crosstalk between metabolic and oncogenic pathways to promote BLBC progression.

Is Programmed Death-Ligand 1 of Prognostic Significance in Triple-Negative Female Mammary Carcinoma?

Introduction

The most widespread female malignancy is breast cancer (BC), considerable percentage of patients with triple-negative BC (TNBC) experience rapid progression, recurrence, and metastasis. BC has not historically been treated as an immunogenic cancer. Nonetheless, several researchers have started to concentrate on immunotherapy.

Aim

The aim of the study is to investigate the immunohistochemical (IHC) expression of programmed death-ligand 1 (PD-L1) by stromal tumor-infiltrating lymphocytes (TILs) and tumor cells (TC) in female (TNBC) and to correlate with pathological features of such tumors, particularly those determine biologic behavior, such as the grade and stage the overall survival.

Methodology

This is a retrospective study which includes 49 paraffin-embedded tumor tissue sections which were collected from breast surgery specimens either radical or conservative of female patients with TNBC. The samples were analyzed immunohistochemically for PD-L1 expression.

Results

There were statistically significant relations among TC PD-L1 expression and TILs PD-L1 expression as well as relations among TILs PD-L1 expression with histologic grade, stromal TILs, and Ki-67 were statistically significant. Correlations between TC PD-L1 expression and N stage, histologic grade, and anatomic stage were statistically significant. Improved survival was detected within TILs PD-L1-positive cases; however, the correlation between the overall survival and PD-L1 expression in both TCs and stromal TIL was not statistically significant.

Conclusion

PD-L1 expressed in tumors with poor prognostic features such as the high grade, advanced T stage, and high Ki-67 index, TILs PD-L1-positive cases experienced improved survival supporting its prognostic significance. However, the correlation with overall survival was not statistically significant.

Advancing Breast Cancer Heterogeneity Analysis: Insights from Genomics, Transcriptomics and Proteomics at Bulk and Single-Cell Levels

Breast cancer continues to pose a significant healthcare challenge worldwide for its inherent molecular heterogeneity. This review offers an in-depth assessment of the molecular profiling undertaken to understand this heterogeneity, focusing on multi-omics strategies applied both in traditional bulk and single-cell levels. Genomic investigations have profoundly informed our comprehension of breast cancer, enabling its categorization into six intrinsic molecular subtypes. Beyond genomics, transcriptomics has rendered deeper insights into the gene expression landscape of breast cancer cells. It has also facilitated the formulation of more precise predictive and prognostic models, thereby enriching the field of personalized medicine in breast cancer. The comparison between traditional and single-cell transcriptomics has identified unique gene expression patterns and facilitated the understanding of cell-to-cell variability. Proteomics provides further insights into breast cancer subtypes by illuminating intricate protein expression patterns and their post-translational modifications. The adoption of single-cell proteomics has been instrumental in this regard, revealing the complex dynamics of protein regulation and interaction. Despite these advancements, this review underscores the need for a holistic integration of multiple 'omics' strategies to fully decipher breast cancer heterogeneity. Such integration not only ensures a comprehensive understanding of breast cancer's molecular complexities, but also promotes the development of personalized treatment strategies.

ICAM-1-suPAR-CD11b Axis Is a Novel Therapeutic Target for Metastatic Triple-Negative Breast Cancer

Accumulating evidence demonstrates that circulating tumor cell (CTC) clusters have higher metastatic ability than single CTCs and negatively correlate with cancer patient outcomes. Along with homotypic CTC clusters, heterotypic CTC clusters (such as neutrophil-CTC clusters), which have been identified in both cancer mouse models and cancer patients, lead to more efficient metastasis formation and worse patient outcomes. However, the mechanism by which neutrophils bind to CTCs remains elusive. In this study, we found that intercellular adhesion molecule-1 (ICAM-1) on triple-negative breast cancer (TNBC) cells and CD11b on neutrophils mediate tumor cell-neutrophil binding. Consequently, CD11b deficiency inhibited tumor cell-neutrophil binding and TNBC metastasis. Furthermore, CD11b mediated hydrogen peroxide (H2O2) production from neutrophils. Moreover, we found that ICAM-1 in TNBC cells promotes tumor cells to secrete suPAR, which functions as a chemoattractant for neutrophils. Knockdown of uPAR in ICAM-1+ TNBC cells reduced lung-infiltrating neutrophils and lung metastasis. Bioinformatics analysis confirmed that uPAR is highly expressed in TNBCs, which positively correlates with higher neutrophil infiltration and negatively correlates with breast cancer patient survival. Collectively, our findings provide new insight into how neutrophils bind to CTC to facilitate metastasis and discover a novel potential therapeutic strategy by blocking the ICAM-1-suPAR-CD11b axis to inhibit TNBC metastasis.

Enhancing plant-derived smart nano inhibitor in targeting mammalian target of rapamycin (mTOR) in breast cancer using Curcuma longa-derived compound curcumin

Breast cancer is a diverse female malignancy; its classification is based on clinical evidence and pathological elucidation. Large public drug screening data databases combined with transcriptome measures have helped develop predictive computational models. Breast cancer is frequent among women worldwide. Several genes increase breast cancer risk. The Mammalian Target of Rapamycin (popularly known as mTOR) is a risk factor mutated in numerous breast carcinoma types. This has caught the scientific community's focus, which is attempting to generate creative, potent, and bio-available ligands for future anti-cancer treatments to establish a practical therapeutic approach. mTOR is a protein kinase involved in cell proliferation, survival, metabolism, and immune response. Activating mTOR promotes cancer growth and spread. To generate a bioavailable and effective mTOR inhibitor, we used computer-aided drug design to study chromones and flavonoids, two naturally occurring chemicals with many biological activities. We used Curcuma longaderived tiny nano-molecules, which can be coated using liposomes to target mTOR to prevent breast cancer growth. The significant interactions of Curcumin were anticipated using molecular docking. It had the highest binding affinity at -12.26 kcal/mol. 100 nanoseconds of molecular dynamic modelling confirmed Curcumin and mTOR receptor interaction. Liposomes are a form of medicine carrier. To improve healthcare, more liposome-like nanostructures are being made. Nanostructures' interactions with living creatures are being studied. Half-life, tissue accumulation, and toxicity have been studied. Future medication distribution may use nanocarriers having a liposome-like form, enabling targeted nano-delivery. Curcumin's interaction with the active site increased the complex's structural stability during its expansion. Our results may help future investigations of Curcumin's efficacy as a possible lead treatment targeting mTOR receptors in breast cancer. Using Curcumin as a potential anti-cancer drug with lipid-coated nano-particles allows for tailored administration.

Ginsenoside Rg3 liposomes regulate tumor microenvironment for the treatment of triple negative breast cancer

OBJECTIVE

To improve the solubility and targeting of Ginsenoside Rg3 (G-Rg3), in the current study, we constructed a novel targeting functional material folic acid -poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate (FA-PEOz-CHMC, FPC) modified G-Rg3 liposomes (FPC-Rg3-L).

METHODS

FPC was synthesized by using folic acid (FA) as a targeted head coupling with acid-activated poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate. The inhibitory effects of the G-Rg3 preparations on mouse breast cancer cells (4T1) were investigated by CCK-8 assay. Paraffin sections of female BALB/c mice viscera were taken for hematoxylin-eosin (H&E) staining after continuous tail vein injection of G-Rg3 preparations. BALB/c mice bearing triple-negative breast cancer (TNBC) were used as animal models to investigate the inhibition of G-Rg3 preparations on tumor growth and improving quality of life. Transforming growth factor-β1 (TGF-β1) and α-smooth muscular actin (α-SMA) were used to investigate the expression of two fibrosis factors in tumor tissues by western blotting.

RESULTS

Compared with G-Rg3 solution (Rg3-S) and Rg3-L, FPC-Rg3-L had a significant inhibitory effect on 4T1 cells (p < .01), and the half maximal inhibitory concentration (IC₅₀) of FPC-Rg3-L was significantly lower (p < .01). The H&E results showed that the injection of FPC-Rg3-L and Rg3-S did not cause damage to the organs of mice. Compared with the control group, tumor growth was significantly inhibited in mice treated with FPC-Rg3-L and G-Rg3 solutions (p < .01).

CONCLUSIONS

This study presents a new and safe treatment for TNBC, reduces the toxic and side effects of the drug, and provides a reference for the efficient use of Chinese herbal medicine components.

Value of genomics- and radiomics-based machine learning models in the identification of breast cancer molecular subtypes: a systematic review and meta-analysis

Background

In the era of precision therapy, early classification of breast cancer (BRCA) molecular subtypes has clinical significance for disease management and prognosis. We explored the accuracy of machine learning (ML) models for early classification of BRCA molecular subtypes through a systematic review of the literature currently available.

Methods

We retrieved relevant studies published in PubMed, EMBASE, Cochrane, and Web of Science until 15 April 2022. A prediction model risk of bias assessment tool (PROBAST) was applied for the assessment of risk of bias of a genomics-based ML model, and the Radiomics Quality Score (RQS) was simultaneously used to evaluate the quality of this radiomics-based ML model. A random effects model was adopted to analyze the predictive accuracy of genomics-based ML and radiomics-based ML for Luminal A, Luminal B, Basal-like or triple-negative breast cancer (TNBC), and human epidermal growth factor receptor 2 (HER2). The PROSPERO of our study was prospectively registered (CRD42022333611).

Results

Of the 38 studies were selected for analysis, 14 ML models were based on gene-transcriptomic, with only 4 external validations; and 43 ML models were based on radiomics, with only 14 external validations. Meta-analysis results showed that c-statistic values of the ML based on radiomics for the identification of BRCA molecular subtypes Luminal A, Luminal B, Basal-like or TNBC, and HER2 were 0.76 [95% confidence interval (CI): 0.60-0.96], 0.78 (95% CI: 0.69-0.87), 0.89 (95% CI: 0.83-0.91), and 0.83 (95% CI: 0.81-0.86), respectively. The c-statistic values of ML based on the gene-transcriptomic analysis cohort for the identification of the previously described BRCA molecular subtypes were 0.96 (95% CI: 0.93-0.99), 0.96 (95% CI: 0.93-0.99), 0.98 (95% CI: 0.95-1.00), and 0.97 (95% CI: 0.96-0.98) respectively. Additionally, the sensitivity of the ML model based on radiomics for each molecular subtype ranged from 0.79 to 0.85, while the sensitivity of the ML model based on gene-transcriptomic was between 0.92 and 0.99.

Conclusions

Both radiomics and gene transcriptomics produced ideal effects on BRCA molecular subtype prediction. Compared with radiomics, gene transcriptomics yielded better prediction results, but radiomics was simpler and more convenient from a clinical point of view.

Migratory Engineering of T Cells for Cancer Therapy

Adoptive cell therapy (ACT) and chimeric antigen receptor (CAR) T cell therapy in particular represents an adaptive, yet versatile strategy for cancer treatment. Convincing results in the treatment of hematological malignancies have led to FDA approval for several CAR T cell therapies in defined refractory diseases. In contrast, the treatment of solid tumors with adoptively transferred T cells has not demonstrated convincing efficacy in clinical trials. One of the main reasons for ACT failure in solid tumors is poor trafficking or access of transferred T cells to the tumor site. Tumors employ a variety of mechanisms shielding themselves from immune cell infiltrates, often translating to only fractions of transferred T cells reaching the tumor site. To overcome this bottleneck, extensive efforts are being undertaken at engineering T cells to improve ACT access to solid tumors. In this review, we provide an overview of the immune cell infiltrate in human tumors and the mechanisms tumors employ toward immune exclusion. We will discuss ways in which T cells can be engineered to circumvent these barriers. We give an outlook on ongoing clinical trials targeting immune cell migration to improve ACT and its perspective in solid tumors.

Expression and Signaling Pathways of Nerve Growth Factor (NGF) and Pro-NGF in Breast Cancer: A Systematic Review

Breast cancer represents the most common type of cancer and is the leading cause of death due to cancer among women. Thus, the prevention and early diagnosis of breast cancer is of primary urgency, as well as the development of new treatments able to improve its prognosis. Nerve Growth Factor (NGF) is a neurotrophic factor involved in the regulation of neuronal functions through the binding of the Tropomyosin receptor kinase A (TrkA) and the Nerve Growth Factor receptor or Pan-Neurotrophin Receptor 75 (NGFR/p75NTR). In addition, its precursor (pro-NGF) can extert biological activity by forming a trimeric complex with NGFR/p75NTR and sortilin, or by binding to TrkA receptors with low affinity. Several examples of in vitro and in vivo evidence show that NGF is both synthesized and released by breast cancer cells, and has mitogen, antiapoptotic and angiogenic effects on these cells through the activation of different signaling cascades that involve TrkA and NGFR/p75NTR receptors. Conversely, pro-NGF signaling has been related to breast cancer invasion and metastasis. Other studies suggested that NGF and its receptors could represent a good diagnostic and prognostic tool, as well as promising therapeutic targets for breast cancer. In this paper, we comprehensively summarize and systematically review the current experimental evidence on this topic. INPLASY ID: INPLASY2022100017.

Chromatin Variants Reveal the Genetic Determinants of Oncogenesis in Breast Cancer

Breast cancer presents as multiple distinct disease entities. Each tumor harbors diverse cell populations defining a phenotypic heterogeneity that impinges on our ability to treat patients. To date, efforts mainly focused on genetic variants to find drivers of inter- and intratumor phenotypic heterogeneity. However, these efforts have failed to fully capture the genetic basis of breast cancer. Through recent technological and analytical approaches, the genetic basis of phenotypes can now be decoded by characterizing chromatin variants. These variants correspond to polymorphisms in chromatin states at DNA sequences that serve a distinct role across cell populations. Here, we review the function and causes of chromatin variants as they relate to breast cancer inter- and intratumor heterogeneity and how they can guide the development of treatment alternatives to fulfill the goal of precision cancer medicine.

Clustering Molecular Subtypes in Breast Cancer, Immunohistochemical Parameters and Risk of Axillary Nodal Involvement

(1) Background: To establish similarities in the risk of axillary lymph node metastasis between different groups of women with breast cancer according to immunohistochemical (IHC) parameters. (2) Methods: Data was collected retrospectively, from 2000 to 2013, of 1058 node-positive breast tumours. All patients were divided according to the St Gallen 2013 criteria and IHC features. The proportion of axillary involvement (pN > pN0; pN > pN1mi; pN > pN1) was calculated for each group. Similarities in axillary nodal dissemination were explored by cluster analysis and association between IHC and risk of axillary disease was studied with multivariate analysis. (3) Results: Among clinico-pathological surrogates of intrinsic subtypes, axillary involvement was more frequent in Luminal-B like HER2 negative (45.8%) and less frequent in Luminal-B HER2 positive (33.8%; p = 0.044). Axillary macroscopic involvement was more frequent in Luminal-B like HER2 negative (37.9%) and HER2 positive (37.8%) and less frequent in Luminal-B HER2 positive (25.5%) and Luminal-A like (25.6%; p = 0.002). Axillary involvement ≥pN2 was significantly less frequent in Luminal-A like (7.4%; p < 0.001). Luminal-A with Luminal-B HER2 positive, and triple-negative with Erb-B2 overexpressing tumours were clustered together regarding any axillary involvement, macroscopic disease or ≥pN2. Among the defined subgroups, axillary metastases were more frequent when Ki67 was higher. In a multivariate analysis, Ki67>14% were associated with a risk of axillary metastases (HR: 1.31; 95% CI, 1.51−6.80; p < 0.037). (4) Conclusions: there are two lymphatic drainage pathways of the breast according to the expression of hormone receptor-related genes. Positive-ER tumors are associated with lower axillary involvement and negative-ER tumors and Ki67 > 14% with higher nodal involvement.

Plant Derived Bioactive Compounds, Their Anti-Cancer Effects and In Silico Approaches as an Alternative Target Treatment Strategy for Breast Cancer: An Updated Overview

Cancer is one of the most common malignant diseases that occur worldwide, among which breast cancer is the second leading cause of death in women. The subtypes are associated with differences in the outcome and were selected for treatments according to the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor. Triple-negative breast cancer, one of the subtypes of breast cancer, is difficult to treat and can even lead to death. If breast cancer is not treated during the initial stages, it may spread to nearby organs, a process called metastasis, through the blood or lymph system. For in vitro studies, MCF-7, MDA-MB-231, MDA-MB-468, and T47B are the most commonly used breast cancer cell lines. Clinically, chemotherapy and radiotherapy are usually expensive and can also cause side effects. To overcome these issues, medicinal plants could be the best alternative for chemotherapeutic drugs with fewer side effects and cost-effectiveness. Furthermore, the genes involved in breast cancer can be regulated and synergized with signaling molecules to suppress the proliferation of breast cancer cells. In addition, nanoparticles encapsulating (nano-encapsulation) medicinal plant extracts showed a significant reduction in the apoptotic and cytotoxic activities of breast cancer cells. This present review mainly speculates an overview of the native medicinal plant derived anti-cancerous compounds with its efficiency, types and pathways involved in breast cancer along with its genes, the mechanism of breast cancer brain metastasis, chemoresistivity and its mechanism, bioinformatics approaches which could be an effective alternative for drug discovery.

Cytotoxicity of synthetic derivatives against breast cancer and multi-drug resistant breast cancer cell lines: a literature-based perspective study

Cancer is the second most killer worldwide causing millions of people to lose their lives every year. In the case of women, breast cancer takes away the highest proportion of mortality rate than other cancers. Due to the mutation and resistance-building capacity of different breast cancer cell lines against conventional therapies, this death rate is on the verge of growth. New effective therapeutic compounds and treatment method is the best way to look out for in this critical time. For instance, new synthetic derivatives/ analogues synthesized from different compounds can be a ray of hope. Numerous synthetic compounds have been seen enhancing the apoptosis and autophagic pathway that directly exerts cytotoxicity towards different breast cancer cell lines. To cease the ever-growing resistance of multi-drug resistant cells against anti-breast cancer drugs (Doxorubicin, verapamil, tamoxifen) synthetic compounds may play a vital role by increasing effectivity, showing synergistic action. Many recent and previous studies have reported that synthetic derivatives hold potentials as an effective anti-breast cancer agent as they show great cytotoxicity towards cancer cells, thus can be used even vastly in the future in the field of breast cancer treatment. This review aims to identify the anti-breast cancer properties of several synthetic derivatives against different breast cancer and multi-drug-resistant breast cancer cell lines with their reported mechanism of action and effectivity.

Opposite Roles of Tumor Cell Proliferation and Immune Cell Infiltration in Postoperative Liver Metastasis of PDAC

Background

Recurrence of liver metastasis after pancreatectomy is often a predictor of poor prognosis. Comprehensive genomic analysis may contribute to a better understanding of the molecular mechanisms of postoperative liver metastasis and provide new therapeutic targets.

Methods

A total of 67 patients from The Cancer Genome Atlas (TCGA) were included in this study. We analyzed differentially expressed genes (DEGs) by R package "DESeq2." Weighted gene co-expression network analysis (WGCNA) was applied to investigate the key modules and hub genes. Immunohistochemistry was used to analyze tumor cell proliferation index and CD4⁺ T cells infiltration.

Results

Functional analysis of DEGs between the liver metastatic and recurrence-free groups was mainly concentrated in the immune response. The liver metastasis group had lower immune and stroma scores and a higher TP53 mutation rate. WGCNA showed that the genes in key modules related to disease-free survival (DFS) and overall survival (OS) were mainly enriched in the cell proliferation process and tumor immune response. Immunohistochemical analysis showed that the pancreatic cancer cells of patients with early postoperative liver metastasis had higher proliferative activity, while the infiltration of CD4⁺ T cells in tumor specimens was less.

Conclusion

Our study suggested that increased immune cell infiltration (especially CD4⁺ T cells) and tumor cell proliferation may play an opposite role in liver metastasis recurrence after pancreatic cancer.

Evading immune surveillance via tyrosine phosphorylation of nuclear PCNA

Increased DNA replication and metastasis are hallmarks of cancer progression, while deregulated proliferation often triggers sustained replication stresses in cancer cells. How cancer cells overcome the growth stress and proceed to metastasis remains largely elusive. Proliferating cell nuclear antigen (PCNA) is an indispensable component of the DNA replication machinery. Here, we show that phosphorylation of PCNA on tyrosine 211 (pY211-PCNA) regulates DNA metabolism and tumor microenvironment. Abrogation of pY211-PCNA blocks fork processivity, resulting in biogenesis of single-stranded DNA (ssDNA) through a MRE11-dependent mechanism. The cytosolic ssDNA subsequently induces inflammatory cytokines through a cyclic GMP-AMP synthetase (cGAS)-dependent cascade, triggering an anti-tumor immunity by natural killer (NK) cells to suppress distant metastasis. Expression of pY211-PCNA is inversely correlated with cytosolic ssDNA and associated with poor survival in patients with cancer. Our results pave the way to biomarkers and therapies exploiting immune responsiveness to target metastatic cancer.

Invasive lobular carcinoma: clinicopathological features and subtypes

Objective

To analyze the characteristics of invasive lobular carcinoma (ILC) compared with invasive ductal carcinoma (IDC) and to investigate the impact of histology on axillary lymph node (ALN) involvement in luminal A subtype tumors.

Methods

We retrospectively analyzed patients diagnosed with ILC or IDC from 2012 to 2016 who underwent surgery. Patients constituted 493 primary early breast cancer cases (82 ILC; 411 IDC).

Results

Compared with IDC, ILC tumors were significantly more likely to be grade 2, estrogen receptor- (ER) positive (+), have a lower proliferation rate (Ki67 <14%), and a higher pathological T stage (pT2–4). The luminal A subtype was significantly more common in ILC compared with IDC. In a multivariate regression model, grade 2, ER+, progesterone receptor-positive, pT2, and pT3 were significantly associated with ILC. Additionally, with the luminal A subtype, ALN involvement (pathological node stage (pN)1–3) was significantly more frequent with ILC versus IDC.

Conclusions

Our data suggest that grade 2, positive hormone receptor status, and higher pathological T stage are associated with ILC. With the luminal A subtype, ALN involvement was more frequent with ILC versus IDC.

A two-pronged photodynamic nanodrug to prevent metastasis of basal-like breast cancer

A two-pronged concept combining photodynamic therapy (PDT) and epithelial-mesenchymal transition (EMT) blockade in a minimalist nanoplatform was proposed to combat basal-like breast cancer (BLBC) metastasis. Based on PDT-mediated tumor killing and epalrestat (Epa)-mediated EMT blockade, as-prepared Ce6/Epa nanoparticles prevented BLBC metastasis effectively in vivo, providing a very promising two-pronged strategy against BLBC metastasis.

MIG-6 is essential for promoting glucose metabolic reprogramming and tumor growth in triple-negative breast cancer

Treatment of triple‐negative breast cancer (TNBC) remains challenging due to a lack of effective targeted therapies. Dysregulated glucose uptake and metabolism are essential for TNBC growth. Identifying the molecular drivers and mechanisms underlying the metabolic vulnerability of TNBC is key to exploiting dysregulated cancer metabolism for therapeutic applications. Mitogen‐inducible gene‐6 (MIG‐6) has long been thought of as a feedback inhibitor that targets activated EGFR and suppresses the growth of tumors driven by constitutive activated mutant EGFR. Here, our bioinformatics and histological analyses uncover that MIG‐6 is upregulated in TNBC and that MIG‐6 upregulation is positively correlated with poorer clinical outcomes in TNBC. Metabolic arrays and functional assays reveal that MIG‐6 drives glucose metabolism reprogramming toward glycolysis. Mechanistically, MIG‐6 recruits HAUSP deubiquitinase for stabilizing HIF1α protein expression and the subsequent upregulation of GLUT1 and other HIF1α‐regulated glycolytic genes, substantiating the comprehensive regulation of MIG‐6 in glucose metabolism. Moreover, our mouse studies demonstrate that MIG‐6 regulates GLUT1 expression in tumors and subsequent tumor growth in vivo. Collectively, this work reveals that MIG‐6 is a novel prognosis biomarker, metabolism regulator, and molecular driver of TNBC.

Molecular classification predicts survival for breast cancer patients in Vietnam: a single institutional retrospective analysis

BACKGROUND

The Bhagarva surrogate molecular subtype definitions classify invasive breast cancer into seven the different subgroups based on immunohistochemical (IHC) criteria according to expression levels of markers as ER, PR, HER2, EGFR and/or basal cytokeratin (CK5/6) which are different in prognosis and responsiveness to adjuvant therapy.

PURPOSE

The present study aimed to classify primary breast cancers and directly compares the prognostic significance of the intrinsic subtypes.

METHODS

The current study was conducted on 522 breast cancer patients who had surgery, but had not received neoadjuvant chemotherapy, from 2011 to 2014. The clinicopathologic characteristics were recorded. IHC staining was performed for ER, PR, HER2, Ki67, CK5/6, EGFR and D2-40 markers. All breast cancer patients were stratified according to Bhagarva criteria. The followed-up patients' survival was analyzed by using Kaplan-Meier and Log-Rank models.

RESULTS

The luminal A (LUMA) was observed at the highest rate (32.5%). Non-basal-like triple negative phenotype (TNB-) and Luminal A HER2-Hybrid (LAHH) were the least common (3.3% in both). LUMA and luminal B (LUMB) were significantly associated with better prognostic features compared to HER2, basal-like triple negative phenotype (TNB+) and TNB-. Statistically significant differences were demonstrated between overall survival (OS), disease-free survival (DFS) and molecular subtypes (P<0.05), of which LUMB and LUMA had the highest rate of OS and DFS being 97.2 and 93.7%; and 97.2 and 90.5%, respectively. Conversely, HER2 revealed the worst prognosis with the lowest prevalence of OS and DFS (72.5 and 69.9%, respectively).

CONCLUSION

The molecular subtypes had a distinct OS and DFS. The intrinsic stratification displayed inversely to clinicopathological features in breast cancer.

Recent Advances in Integrative Multi-Omics Research in Breast and Ovarian Cancer

The underlying molecular heterogeneity of cancer is responsible for the dynamic clinical landscape of this disease. The combination of genomic and proteomic alterations, including both inherited and acquired mutations, promotes tumor diversity and accounts for variable disease progression, therapeutic response, and clinical outcome. Recent advances in high-throughput proteogenomic profiling of tumor samples have resulted in the identification of novel oncogenic drivers, tumor suppressors, and signaling networks; biomarkers for the prediction of drug sensitivity and disease progression; and have contributed to the development of novel and more effective treatment strategies. In this review, we will focus on the impact of historical and recent advances in single platform and integrative proteogenomic studies in breast and ovarian cancer, which constitute two of the most lethal forms of cancer for women, and discuss the molecular similarities of these diseases, the impact of these findings on our understanding of tumor biology as well as the clinical applicability of these discoveries.

Prognostic values of tumoral MMP2 and MMP9 overexpression in breast cancer: a systematic review and meta-analysis

Background

Breast cancer (BC) is a leading cause of cancer-related death in females worldwide. Previous studies have demonstrated that matrix metalloproteinases (MMPs) play key roles in metastasis and are associated with survival in various cancers. The prognostic values of MMP2 and MMP9 expression in BC have been investigated, but the results remain controversial. Thus, we performed the present meta-analysis to investigate the associations between MMP2/9 expressions in tumor cells with clinicopathologic features and survival outcome in BC patients.

Methods

Eligible studies were searched in PubMed, Web of Science, EMBASE, CNKI and Wanfang databases. The associations of MMP2/9 overexpression in tumor cells with overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS) were assessed by hazard ratio (HR) and 95% confidence interval (CI). The associations of MMP2/9 overexpression with clinicopathological features were investigated by calculating odds ratio (OR) and 95% CI. Subgroup analysis, sensitivity analysis, meta-regression, and analysis for publication bias were performed.

Results

A total of 41 studies comprising 6517 patients with primary BC were finally included. MMP2 overexpression was associated with an unfavorable OS (HR = 1.60, 95% CI 1.33 –1.94, P < 0.001) while MMP9 overexpression predicted a shorter OS (HR = 1.52, 95% CI 1.30 –1.77, P < 0.001). MMP2 overexpression conferred a higher risk to distant metastasis (OR = 2.69, 95% CI 1.35–5.39, P = 0.005) and MMP9 overexpression correlated with lymph node metastasis (OR = 2.90, 95% CI 1.86 – 4.53, P < 0.001). Moreover, MMP2 and MMP9 overexpression were both associated with higher clinical stage and histological grade in BC patients. MMP9 overexpression was more frequent in patients with larger tumor sizes.

Conclusions

Tumoral MMP2 and MMP9 are promising markers for predicting the prognosis in patients with BC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07860-2.

Basal-like breast cancer with low TGFβ and high TNFα pathway activity is rich in activated memory CD4 T cells and has a good prognosis

Basal-like breast cancer (BLBC) is a type of high-grade invasive breast cancer with high risk of recurrence, metastases, and poor survival. Immune activation in BLBC is a key factor that influences both cancer progression and therapeutic response, although its molecular mechanisms are not well clarified. In this study, we examined five cancer immunity-related pathways (IFNα, IFNγ, STAT3, TGFβ and TNFα) in four large independent breast cancer cohorts (n = 6,381) and their associations with the prognosis of breast cancer subtypes. Activities of the 5 pathways were calculated based on corresponding pathway signatures and associations between pathways and clinical outcomes were examined by survival analysis. Among the five PAM50-based subtypes, BLBC had the highest IFNα, IFNγ, TNFα pathway activities, and the lowest TGFβ activity. The IFNα, IFNγ, TNFα pathway activities were negatively correlated with BLBC recurrence. In contrast, positive association and no association with BLBC recurrence were observed for TGFβ and STAT3 pathways, respectively. TNFα/TGFβ pathway combination improved the prediction of recurrence and chemotherapy response of BLBCs. Immune cell subset analysis in BLBC showed that M0, M1 and M2 macrophage levels were associated with either TNFα or TGFβ pathways, whereas the level of activated memory CD4 T cells were associated with both pathways. Moreover, this T cell subset was most abundant in BLBCs with low TGFβ and high TNFα pathway activities. These results suggested that cooperation of TNFα and TGFβ signaling may be involved in the regulation of memory T cells and anti-cancer immunity in BLBCs. Our data also demonstrate that TNFα/TGFβ pathway combination may represent a better biomarker for BLBC prognosis and clinical management.

Association Between Plasma Diacetylspermine and Tumor Spermine Synthase With Outcome in Triple-Negative Breast Cancer

BACKGROUND

MYC is an oncogenic driver of development and progression in triple-negative breast cancer (TNBC). Ornithine decarboxylase, the rate-limiting enzyme in polyamine metabolism, is a transcriptional target of MYC. We therefore hypothesized that a plasma polyamine signature may be predictive of TNBC development and progression.

METHODS

Using liquid chromatography mass spectrometry, polyamine levels were determined in plasma samples from newly diagnosed patients with TNBC (n = 87) and cancer-free controls (n = 115). Findings were validated in plasma samples from an independent prospective cohort of 54 TNBC, 55 estrogen receptor negative (ER-) and progesterone receptor negative (PR-) and HER2 positive (HER2+), and 73 ER+ case patients, and 30 cancer-free control subjects. Gene expression data and clinical data for 921 and 2359 breast cancer tumors were obtained from The Cancer Genome Atlas repository and the Oncomine database, respectively. Relationships between plasma diacetylspermine (DAS) and tumor spermine synthase (SMS) mRNA expression with metastasis-free survival and overall survival were determined using Cox proportional hazard models; Fisher exact tests were used to assess risk of distant metastasis in relation to tumor SMS mRNA expression.

RESULTS

An increase in plasma DAS, a catabolic product of spermine mediated through SMS, was observed in the TNBC subtype of breast cancer. Plasma levels of DAS in TNBC associated with increased risk of metastasis (plasma DAS value ≥ 1.16, hazard ratio = 3.06, 95% confidence interval [CI] = 1.15 to 8.13, two-sided P = .03). SMS mRNA expression in TNBC tumor tissue was also found to be predictive of poor overall survival (top 25th percentile hazard ratio = 2.06, 95% CI = 1.04 to 4.08, one-sided P = .04) and increased risk of distant metastasis in TNBC (comparison of lowest SMS quartile [reference] to highest SMS quartile relative risk = 1.90, 95% CI = 0.97 to 4.06, one-sided Fisher exact test P=.03).

CONCLUSIONS

Metabolomic profiling identified plasma DAS as a predictive marker for TNBC progression and metastasis.

Triple Negative Breast Cancer: A Review of Present and Future Diagnostic Modalities

Triple-negative breast cancer (TNBC) is an aggressive breast type of cancer with no expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2). It is a highly metastasized, heterogeneous disease that accounts for 10-15% of total breast cancer cases with a poor prognosis and high relapse rate within five years after treatment compared to non-TNBC cases. The diagnostic and subtyping of TNBC tumors are essential to determine the treatment alternatives and establish personalized, targeted medications for every TNBC individual. Currently, TNBC is diagnosed via a two-step procedure of imaging and immunohistochemistry (IHC), which are operator-dependent and potentially time-consuming. Therefore, there is a crucial need for the development of rapid and advanced technologies to enhance the diagnostic efficiency of TNBC. This review discusses the overview of breast cancer with emphasis on TNBC subtypes and the current diagnostic approaches of TNBC along with its challenges. Most importantly, we have presented several promising strategies that can be utilized as future TNBC diagnostic modalities and simultaneously enhance the efficacy of TNBC diagnostic.

Diagnostic and therapeutic ERβ, HER2, BRCA biomakers in the histological subtypes of lung adenocarcinoma according to the IASLC/ATS/ERS classification

Several studies revealed that non-small cell lung cancers (NSCLCs) frequently express ER, PR, HER2 and carry BRCA mutation. However, these markers in histological subtypes of lung adenocarcinoma have not been thoroughly investigated. We retrospectively evaluated a total of 640 lung adenocarcinoma samples for ERα, ERβ, PR and HER2 expression by immunohistochemistry and western-blotting, for EGFR and BRCA mutation by real-time PCR and sequencing. Furthermore, HER2 amplification and mutation were explored in samples harboring immunopositivity HER2 using fluorescence in situ hybridization and real-time PCR, respectively. The micropapillary and invasive mucinous predominant adenocarcinoma were frequently detected the higher level of cytoplasmic ERβ (64.9% and 56.6%), HER2 (68.1% and 60.1%) protein expression. But, amplification of HER2 was detected in only three cases (3/110, 2.7%) and 26 HER2 mutations in 110 cases were identified (23.6%) in the HER2 immunopositivity patients. Logistic regression analysis showed that cytoplasmic ERβ (P = 0.032) and HER2 (P = 0.015) expression were independently associated with EGFR mutation. 8 patients (8/640, 1.25%) harbored pathogenic BRCA mutations, 6 with germline BRCA mutations and 2 with somatic BRCA1 mutations were detected with lacking ERβ, PR and HER2 expression. Acinar predominant adenocarcinoma had the higher percentage of BRCA mutations than other subtypes. A systematic examination of ERβ, HER2 and BRCA biomarkers could potentially be useful to diagnosis and identify patients with the histological subtypes of lung adenocarcinoma, who might benefit from the further individualized treatment of anti-hormone, anti-HER2 and/or PARP inhibitors therapeutics.

Breast Cancer Stem Cells: Biomarkers, Identification and Isolation Methods, Regulating Mechanisms, Cellular Origin, and Beyond

Despite recent advances in diagnosis and treatment, breast cancer (BC) is still a major cause of cancer-related mortality in women. Breast cancer stem cells (BCSCs) are a small but significant subpopulation of heterogeneous breast cancer cells demonstrating strong self-renewal and proliferation properties. Accumulating evidence has proved that BCSCs are the driving force behind BC tumor initiation, progression, metastasis, drug resistance, and recurrence. As a heterogeneous disease, BC contains a full spectrum of different BC subtypes, and different subtypes of BC further exhibit distinct subtypes and proportions of BCSCs, which correspond to different treatment responses and disease-specific outcomes. This review summarized the current knowledge of BCSC biomarkers and their clinical relevance, the methods for the identification and isolation of BCSCs, and the mechanisms regulating BCSCs. We also discussed the cellular origin of BCSCs and the current advances in single-cell lineage tracing and transcriptomics and their potential in identifying the origin and lineage development of BCSCs.

Modulatory Role of microRNAs in Triple Negative Breast Cancer with Basal-Like Phenotype

Development of new research, classification, and therapeutic options are urgently required due to the fact that TNBC is a heterogeneous malignancy. The expression of high molecular weight cytokeratins identifies a biologically and clinically distinct subgroup of TNBCs with a basal-like phenotype, representing about 75% of TNBCs, while the remaining 25% includes all other intrinsic subtypes. The triple negative phenotype in basal-like breast cancer (BLBC) makes it unresponsive to endocrine therapy, i.e., tamoxifen, aromatase inhibitors, and/or anti-HER2-targeted therapies; for this reason, only chemotherapy can be considered an approach available for systemic treatment even if it shows poor prognosis. Therefore, treatment for these subgroups of patients is a strong challenge for oncologists due to disease heterogeneity and the absence of unambiguous molecular targets. Dysregulation of the cellular miRNAome has been related to huge cellular process deregulations underlying human malignancy. Consequently, epigenetics is a field of great promise in cancer research. Increasing evidence suggests that specific miRNA clusters/signatures might be of clinical utility in TNBCs with basal-like phenotype. The epigenetic mechanisms behind tumorigenesis enable progress in the treatment, diagnosis, and prevention of cancer. This review intends to summarize the epigenetic findings related to miRNAome in TNBCs with basal-like phenotype.

Molecular subtypes of triple-negative breast cancer: understanding of subtype categories and clinical implication

BACKGROUND

Triple-negative breast cancer (TNBC) is a heterogeneous entity that encompasses several subtypes with distinct molecular characteristics. The patients with TNBCs show unpredictable response to the chemotherapy, and further there is the lack of effective agents. Thus, many studies have been underway to discover targeted therapy suitable for patients with specific genetic alterations in each molecular subtypes. TNBCs are classified as four major molecular subtypes according to the gene expression patterns. These are luminal androgen receptor (LAR), mesenchymal-like, immunomodulatory (IM), and basal-like types.

CONCLUSION

Here, we discuss the unique molecular features of each subtype as well as promising targets for anti-cancer therapy.

The Tumor Microenvironment of Primitive and Metastatic Breast Cancer: Implications for Novel Therapeutic Strategies

Breast cancer evolves thanks to a dense and close interaction with the surrounding tumor microenvironment (TME). Fibroblasts, leukocytes, blood and lymphatic endothelial cells and extracellular matrix are the constituents of this entity, and they synergistically play a pivotal role in all of the stages of breast cancer development, from its onset to its metastatic spread. Moreover, it has been widely demonstrated that variations to the TME can correspond to prognosis variations. Breast cancer not only modulates the transformation of the environment within the mammary gland, but the same process is observed in metastases as well. In this minireview, we describe the features of TME within the primitive breast cancer, throughout its evolution and spread into the main metastatic sites.

Drug Repurposing for Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is the most aggressive type of breast cancer which presents a high rate of relapse, metastasis, and mortality. Nowadays, the absence of approved specific targeted therapies to eradicate TNBC remains one of the main challenges in clinical practice. Drug discovery is a long and costly process that can be dramatically improved by drug repurposing, which identifies new uses for existing drugs, both approved and investigational. Drug repositioning benefits from improvements in computational methods related to chemoinformatics, genomics, and systems biology. To the best of our knowledge, we propose a novel and inclusive classification of those approaches whereby drug repurposing can be achieved in silico: structure-based, transcriptional signatures-based, biological networks-based, and data-mining-based drug repositioning. This review specially emphasizes the most relevant research, both at preclinical and clinical settings, aimed at repurposing pre-existing drugs to treat TNBC on the basis of molecular mechanisms and signaling pathways such as androgen receptor, adrenergic receptor, STAT3, nitric oxide synthase, or AXL. Finally, because of the ability and relevance of cancer stem cells (CSCs) to drive tumor aggressiveness and poor clinical outcome, we also focus on those molecules repurposed to specifically target this cell population to tackle recurrence and metastases associated with the progression of TNBC.

Estrogen Actions in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) lacks estrogen receptor (ER) α, but the expression of estrogen receptors ERβ and G protein-coupled estrogen receptor 1 (GPER-1) is able to trigger estrogen-responsivity in TNBC. Estrogen signaling in TNBC can also be activated and modulated by the constitutively active estrogen-related receptors (ERRs). In this review article, we discuss the role of ERβ and GPER-1 as mediators of E2 action in TNBC as well as the function of ERRs as activators and modulators of estrogen signaling in this cancer entity. For this purpose, original research articles on estrogen actions in TNBC were considered, which are listed in the PubMed database. Additionally, we performed meta-analyses of publicly accessible integrated gene expression and survival data to elucidate the association of ERβ, GPER-1, and ERR expression levels in TNBC with survival. Finally, options for endocrine therapy strategies for TNBC were discussed.

Practical classification of triple-negative breast cancer: intratumoral heterogeneity, mechanisms of drug resistance, and novel therapies

Triple-negative breast cancer (TNBC) is not a unique disease, encompassing multiple entities with marked histopathological, transcriptomic and genomic heterogeneity. Despite several efforts, transcriptomic and genomic classifications have remained merely theoretic and most of the patients are being treated with chemotherapy. Driver alterations in potentially targetable genes, including PIK3CA and AKT, have been identified across TNBC subtypes, prompting the implementation of biomarker-driven therapeutic approaches. However, biomarker-based treatments as well as immune checkpoint inhibitor-based immunotherapy have provided contrasting and limited results so far. Accordingly, a better characterization of the genomic and immune contexture underpinning TNBC, as well as the translation of the lessons learnt in the metastatic disease to the early setting would improve patients' outcomes. The application of multi-omics technologies, biocomputational algorithms, assays for minimal residual disease monitoring and novel clinical trial designs are strongly warranted to pave the way toward personalized anticancer treatment for patients with TNBC.

Exosomes as Biomarkers of Human and Feline Mammary Tumours; A Comparative Medicine Approach to Unravelling the Aggressiveness of TNBC

Comparative oncology is defined as the discipline that integrates naturally occurring cancers seen in veterinary medicine, into more general studies of cancer biology and therapy in humans, including the study of cancer-pathogenesis and new cancer treatments. While experimental studies in mice and rodents offer several advantages, including a wealth of genetic information, reduced variation and short generation intervals, their relevance in cancer biology is somewhat limited. Toward this end, as the biomedical research community works to make the promise of precision medicine a reality, more efficient animal cohort studies are critical. Like humans, companion animals such as cats and dogs living in family homes, are exposed to environmental factors that may influence the development of disease. Furthermore, it has been shown that the basic biochemical and physiological processes of companion animals more closely resemble humans compared to rodents. Research has demonstrated that female domestic cats (Felis catus) may represent a comparative model for investigation of mammary carcinogenesis, and in particular, Triple Negative Breast Cancer (TNBC). TNBC is a subtype of breast cancer that typically lacks the expression of the oestrogen receptor (ER), progesterone receptor (PR), and does not overexpress the human epidermal growth factor receptor 2 (HER2). An exciting and rapidly expanding area in cancer biology is the study of exosomes. Exosomes are nanoparticles released from cells and have been found in biological fluids of humans, domestic cats and dogs. In addition to their role as biomarkers, exosomes are implicated in the pathogenesis of certain diseases, including cancer. This review explores the current understanding of exosome biology in human TNBC, and of the potential benefits of comparative research in naturally-occurring mammary tumours in companion animals.

Prognostic and predictive value of monocarboxylate transporter 4 in patients with breast cancer

The Warburg effect explains the large amount of lactic acid that tumour cells produce to establish and maintain the acidic characteristics of the tumour microenvironment, which contributes to the migration, invasion and angiogenesis of tumour cells. Monocarboxylate transporter 4 (MCT-4) is a key marker of tumour glycolysis and lactic acid production; however, the role of MCT-4 in breast cancer remains unclear. In the present study, immunohistochemistry (IHC) was used to detect the expression levels of MCT-4 in tissue microarrays of 145 patients diagnosed with invasive ductal breast cancer. The IHC score was used to assess the intensity of staining and the proportion of positive cells. Western blotting and reverse transcription-quantitative PCR were also performed to detect the expression levels of MCT-4 in 30 pairs of breast cancer tissues and adjacent normal tissues. In vitro experiments (EdU incoporation and Cell Counting Kit-8) were performed to examine the role of MCT-4 in the breast cancer MCF-7 cell line. The results of the present study indicated that high MCT-4 expression was associated with pT status (P=0.018), oestrogen receptor (ER) status (P=0.001), progesterone receptor (PR) status (P=0.024), Ki67 index (P=0.043) and androgen receptor (AR) status (P=0.033). In addition, an association between MCT-4 expression and pathological grade was observed (P=0.030). Furthermore, univariate (P=0.027) and multivariate (P=0.001) survival analysis revealed that MCT-4 expression and lymph node involvement were significant independent predictors of breast cancer prognosis. In addition, silencing MCT-4 expression attenuated breast cancer cell viability. Therefore, MCT-4 may be used as a potential predictor of invasive breast cancer.

Pathology of triple negative breast cancer

Triple negative breast cancer (TNBC) is a subtype of breast tumor lacking hormone receptors expression and HER2 gene amplification and represents 24 % of newly diagnosed breast neoplasms. In this review, pathological aspects of triple-negative breast cancer are illustrated, with particular attention to the seminal studies that defined this subtype of breast cancer by a molecular point of view. This paper also focuses on practical issues raised in clinical routine by the introduction of genetic expression breast cancer profiling and the innovative prognostic and predictive impact on triple-negative breast cancer pathology. Moreover, histopathological aspects of triple-negative neoplasms are also mentioned, underlying the importance of histologic diagnosis of particular cancer subtypes with decisive impact on clinical outcome. Importantly, focus on new therapeutic frontier represented by immunotherapy is illustrated, with particular mention of immune checkpoint inhibitors introduction in TNBC therapy and their impact on future treatments.

Focus on Triple-Negative Breast Cancer: Potassium Channel Expression and Clinical Correlates

Despite improvements in early diagnosis and treatment, breast cancer is still a major health problem worldwide. Among breast cancer subtypes, the most challenging and harder to treat is represented by triple-negative molecular subtype. Due to its intrinsic features this subtype cannot be treated neither with hormonal therapy (since it does not express estrogen or progesterone receptors) nor with epidermal growth factor receptor 2 (HER2) inhibitors (as it does not express high levels of this protein). For these reasons, the standard of care for these patients is represented by a combination of surgery, radiation therapy and chemotherapy. In this scenario, searching for novel biomarkers that might help both in diagnosis and therapy is mandatory. In the last years, it was shown that different families of potassium channels are overexpressed in primary breast cancers. The altered ion channel expression may be useful for diagnostic and therapeutic purposes due to some peculiar characteristics of this class of molecules. Ion channels are defined as pore-forming transmembrane proteins regulating passive ion fluxes in the cells. Ion channels represent good potential markers since, being localized at the plasma membrane level, their detection and block with specific drugs and antibodies might be fast and tunable. This review focuses on triple-negative breast cancers and recapitulates the current knowledge about potassium channels' clinical relevance and their potential use in the clinical setting, for triple-negative breast cancer diagnosis and therapy.

Neoadjuvant chemotherapy modifies serum pyrrolidone carboxypeptidase specific activity in women with breast cancer and influences circulating levels of GnRH and gonadotropins

PURPOSE

Functional studies have demonstrated that gonadotropin-releasing hormone (GnRH) regulates cell proliferation, apoptosis, and tissue remodeling. GnRH is metabolized by the proteolytic regulatory enzyme pyrrolidone carboxypeptidase (Pcp) (E.C. 3.4.19.3), which is an omega peptidase widely distributed in fluids and tissues. We previously reported a decrease in both rat and human Pcp activity in breast cancer, suggesting that GnRH may be an important local hormonal factor in the pathogenesis of breast cancer. Recently, we have described that postmenopausal women with breast cancer show lower levels of serum Pcp activity than control postmenopausal women. To determine the effect of neoadjuvant chemotherapy (NACT) on serum Pcp specific activity and circulating levels of GnRH, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and steroid hormones 17-ß-estradiol and progesterone in pre- and postmenopausal women diagnosed with infiltrating ductal carcinoma.

METHODS

Serum Pcp activity was measured fluorometrically using pyroglutamyl-ß-naphthylamide. Circulating GnRH levels were dosed using a commercial RIA kit. Circulating LH and FSH levels were measured by enzyme immunoassays. Levels of steroid hormones were measured in serum samples by dissociation-enhanced lanthanide fluorescence immunoassay.

RESULTS AND CONCLUSION

Our results show the effect of NACT on the hypothalamic-pituitary axis, with the consequent alteration of circulating gonadotropins in premenopausal women with breast cancer. However, the results obtained in postmenopausal women with breast cancer treated with NACT, that is, the significant decrease in the concentration of GnRH and FSH compared to control postmenopausal women, differ from those obtained for premenopausal women. The only difference between pre- and postmenopausal women is their hormonal profile at the beginning of the study, that is, the presence of menopause and the consequent alteration of the hypothalamic-pituitary-gonadal axis.

Destabilization of β-catenin and RAS by targeting the Wnt/β-catenin pathway as a potential treatment for triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a severe and heterogeneous disease that lacks an approved targeted therapy and has a poor clinical outcome to chemotherapy. Although the RAS-ERK signaling axis is rarely mutated in TNBC, ~50% of TNBCs show an increased copy number and overexpression of epidermal growth factor receptor (EGFR). However, EGFR-targeted therapies have offered no improvement in patient survival, underscoring the need to explore downstream targets, including RAS. We found that both β-catenin and RAS, as well as epidermal growth factor receptor (EGFR), are overexpressed and correlated with one another in tumor tissues of TNBC patients. KYA1797K, an Axin-binding small molecule reducing β-catenin and RAS expression via degradation and suppressing EGFR expression via transcriptional repression, inhibited the proliferation and the metastatic capability of stable cell lines as well as patient-derived cells (PDCs) established from TNBC patient tissues. KYA1797K also suppressed the stemness of 3D-cultured PDCs and xenografted tumors established by using residual tumors from TNBC patients and those established by the TNBC cell line. Targeting both the Wnt/β-catenin and RAS-ERK pathways via small molecules simultaneously reducing the levels of β-catenin, RAS, and EGFR could be a potential therapeutic approach for TNBC.

The triple-negative breast cancer (TNBC), a highly aggressive form of breast cancer may be susceptible to drug therapy that targets two critical signaling pathways, one that governs cell fate and the other that controls the cell cycle. Researchers from Yonsei University in Seoul, South Korea, had previously synthesized a small-molecule called KYA1797K and found that could lower levels of the proteins, β-catenin (a master regulator of cell fate decisions) and RAS (which controls cell division), in colorectal cancer cells. Now, Kang-Yell Choi, Soonmyung Paik, and colleagues have shown that KYA1797K has the same effects on β-catenin and RAS levels in cells taken from patients with TNBC. In cell lines and mouse models, KY1797K suppressed the proliferation and metastatic capability of TNBC, highlighting the therapeutic potential of this strategy degrading both β-catenin and RAS.

FOXF2 deficiency accelerates the visceral metastasis of basal-like breast cancer by unrestrictedly increasing TGF-β and miR-182-5p

The mesenchymal transcription factor forkhead box F2 (FOXF2) is a critical regulator of embryogenesis and tissue homeostasis. Our previous studies demonstrated that FOXF2 is ectopically expressed in basal-like breast cancer (BLBC) cells and that FOXF2 deficiency promotes the epithelial-mesenchymal transition and aggressiveness of BLBC cells. In this study, we found that FOXF2 controls transforming growth factor-beta (TGF-β)/SMAD signaling pathway activation through transrepression of TGF-β-coding genes in BLBC cells. FOXF2-deficient BLBC cells adopt a myofibroblast-/cancer-associated fibroblast (CAF)-like phenotype, and tend to metastasize to visceral organs by increasing autocrine TGF-β signaling and conferring aggressiveness to neighboring cells by increasing paracrine TGF-β signaling. In turn, TGF-β silences FOXF2 expression through upregulating miR-182-5p, a posttranscriptional regulator of FOXF2 and inducer of metastasis. In addition to mediating a reciprocal repression loop between FOXF2 and TGF-β through direct transrepression by SMAD3, miR-182-5p forms a reciprocal repression loop with FOXF2 that directly transrepresses MIR182 expression. Therefore, FOXF2 deficiency accelerates the visceral metastasis of BLBC through unrestricted increases in autocrine and paracrine TGF-β signaling, and miR-182-5p expression. Our findings provide novel mechanisms underlying the roles of TGF-β, miR-182-5p, and FOXF2 in accelerating BLBC dissemination and metastasis, and may facilitate the development of therapeutic strategies for aggressive BLBC.

Nuclear translocation of PLSCR1 activates STAT1 signaling in basal-like breast cancer

Rationale: Basal-like breast cancer (BLBC) is associated with high grade, distant metastasis, and poor prognosis; however, the mechanism underlying aggressiveness of BLBC is still unclear. Emerging evidence has suggested that phospholipid scramblase 1 (PLSCR1) is involved in tumor progression. Here, we aimed to study the possible involvement and molecular mechanisms of PLSCR1 contributing to the aggressive behavior of BLBC.

Methods: The potential functions of PLSCR1 in breast cancer cells were assessed by Western blotting, colony formation, migration and invasion, Cell Counting Kit-8 assay, mammosphere formation and flow cytometry. The relationship between nuclear translocation of PLSCR1 and transactivation of STAT1 was examined by immunostaining, co-IP, ChIP, and quantitative reverse transcription PCR. The effect of PLSCR1 expression on BLBC cells was determined by in vitro and in vivo tumorigenesis and a lung metastasis mouse model.

Results: Compared to other subtypes, PLSCR1 was considerably increased in BLBC. Phosphorylation of PLSCR1 at Tyr 69/74 contributed to the nuclear translocation of this protein. PLSCR1 was enriched in the promoter region of STAT1 and enhanced STAT3 binding to the STAT1 promoter, resulting in transactivation of STAT1; STAT1 then enhanced cancer stem cell (CSC)-like properties that promoted BLBC progression. The knockdown of PLSCR1 led to significant inhibitory effects on proliferation, migration, invasion, tumor growth and lung metastasis of BLBC cells. Clinically, high PLSCR1 expression was strongly correlated with large tumor size, high grade, metastasis, chemotherapy resistance, and poor survival, indicating poor prognosis in breast cancer patients.

Conclusions: Our data show that overexpression and nuclear translocation of PLSCR1 provide tumorigenic and metastatic advantages by activating STAT1 signaling in BLBC. This study not only reveals a critical mechanism of how PLSCR1 contributes to BLBC progression, but also suggests potential prognostic indicators and therapeutic targets for this challenging disease.

Fibrosis and cancer: A strained relationship

Tumors are characterized by extracellular matrix (ECM) deposition, remodeling, and cross-linking that drive fibrosis to stiffen the stroma and promote malignancy. The stiffened stroma enhances tumor cell growth, survival and migration and drives a mesenchymal transition. A stiff ECM also induces angiogenesis, hypoxia and compromises anti-tumor immunity. Not surprisingly, tumor aggression and poor patient prognosis correlate with degree of tissue fibrosis and level of stromal stiffness. In this review, we discuss the reciprocal interplay between tumor cells, cancer associated fibroblasts (CAF), immune cells and ECM stiffness in malignant transformation and cancer aggression. We discuss CAF heterogeneity and describe its impact on tumor development and aggression focusing on the role of CAFs in engineering the fibrotic tumor stroma and tuning tumor cell tension and modulating the immune response. To illustrate the role of mechanoreciprocity in tumor evolution we summarize data from breast cancer and pancreatic ductal carcinoma (PDAC) studies, and finish by discussing emerging anti-fibrotic strategies aimed at treating cancer.

Bioinformatics Analysis to Screen the Key Prognostic Genes in Tumor Microenvironment of Bladder Cancer

Bladder cancer (BLCA) is the fifth most common cancer and has the features of low survival rate and high morbidity and mortality. The Cancer Genome Atlas (TCGA) is a pool of global gene expression profile and contains huge amounts of cancer genomics data, which makes it possible to inquire the relationship between gene expression and prognosis of a series of malignant tumors including BLCA. Immune and stromal cells are two major components of tumor microenvironment (TME) which play an important role in judging the prognosis of tumor and influencing the progression of malignant, inflammatory, and metabolic disorders. In our study, we conducted a quantitative analysis of immune and stromal elements based on the ESTIMATE algorithm and thus divided BLCA cases into high and low groups. Then the differentially expressed genes closely related to tumor prognosis between groups were identified and had been shown to correlate with immune response and stromal alterations, which was further confirmed by functional enrichment analysis and protein-protein interaction networks. We validated those genes through BLCA dates downloaded from ArrayExpress and thus got the marker genes to predict prognosis of BLCA. Additionally, immune cell infiltration analysis explored the correlation between the verified genes and immune cells. In conclusion, we identified a series of TME-related genes that assess the prognosis and explored the interaction between TME and tumor prognosis to guide clinical individualized treatment.

Clinicopathological and immunohistochemical characteristics of breast cancer patients from Northeast India with special reference to triple negative breast cancer: A prospective study

BACKGROUND

Molecular pathogenesis of Triple-negative breast cancer (TNBC) is inconclusively documented from resource limited countries and hence there is a lack of available targeted therapy for clinical interventions. Compared to other breast cancer subtypes, TNBC is more aggressive, higher recurrence rate, and higher prevalence in younger premenopausal women. Sporadic literature indicates predominance of TNBC in all reported breast cancer cases from Northeast India.

AIM

This study was conducted to evaluate the candidature of panel of key molecular markers involved in the development and progression of TNBC for prognosis and futuristic tailored targeted therapy.

MATERIALS AND METHODS

We analyzed the clinicopathological characterized and immunohistochemically screened the differential expression of key molecular markers involved in the development and progression of in TNBC cases vis-a-vis non-TNBC and autopsy-based control samples.

RESULTS

TNBC tends to display at an early reproductive age and is more aggressive in nature. Further, the differential expression of 2 specific markers viz., epidermal growth factor receptor (EGFR) and FolR1 was higher in TNBC cases compared to controls and non-TNBC (both in terms of susceptibility and specificity), clinical staging in TNBC cases (severity) and mortality (outcome). Although Ki67 and vascular endothelial growth factor expression also correlated with severity and outcome of the disease but their differences in non-TNBC cases were not significantly differentiable compared to TNBC.

CONCLUSIONS

The study indicates that EGFR and FolR1 could serve as useful biomarkers to determine TNBC prognosis. Further studies will be needed to evaluate EGFR and Folate pathways in order to screen out the molecular targets which may be meaningfully used for clinical stratification, intervention, and treatment.

Composition and plasticity of triple-negative breast carcinoma-infiltrating regulatory T cells

Low Foxp3⁺ regulatory T-cell (Treg) presence in the tumor-infiltrating lymphocytes (TILs) is considered favorable in breast cancer, and numerous CD25-targeting agents have been applied in the attempt to remove Foxp3⁺ Treg cells, which typically present CD4⁺ CD25^+/hi surface phenotype. However, CD25 is not Treg-exclusive and can be upregulated by effector T cells. Hence, CD25 depletion may cause the elimination of activated T cells that are responding to tumor-specific antigens. In this study, the composition and function of CD4⁺ CD25⁺ cells inside the microenvironment of triple-negative breast carcinoma (TNBC) were investigated. Directly ex vivo, the Foxp3⁺ Treg cells represented a minor subset in total CD4⁺ CD25⁺ TILs. Significant differences were observed in the expression of Treg-associated molecules between CD4⁺ CD25⁺ Foxp3⁺ TILs and CD4⁺ CD25⁺ Foxp3^- TILs. While both the CD4⁺ CD25⁺ Foxp3⁺ and the CD4⁺ CD25⁺ Foxp3^- TILs could express CTLA-4 and LAG-3, the expression levels were significantly higher in CD4⁺ CD25⁺ Foxp3⁺ TILs than in CD4⁺ CD25⁺ Foxp3^- TILs. Upon TCR stimulation, the expression of TGF-beta was significantly higher in CD4⁺ CD25⁺ Foxp3⁺ TILs, while the expression of IL-10 was significantly higher in CD4⁺ CD25⁺ Foxp3^- TILs. These differences were conserved in the blood counterparts of these cells. Interestingly, the level of CD25⁺ Foxp3⁺ cells in circulating CD4⁺ T cells was positively correlated with the level of CD25⁺ Foxp3⁺ cells in CD4⁺ TILs, but the level of CD25⁺ Foxp3^- cells in circulating CD4⁺ T cells was not associated with the level of CD25⁺ Foxp3^- cells in CD4⁺ TILs. Th17-polarizing medium could readily remodel CD4⁺ CD25⁺ Foxp3^- , but not CD4⁺ CD25⁺ Foxp3⁺ , T cells into RORgammat and IL-17-expressing T cells, demonstrating stronger plasticity of the former subset. Together, these data demonstrated that the CD4⁺ CD25⁺ TILs were composed of distinctive Foxp3^- and Foxp3⁺ cells, with the former representing the major subset. The antigen specificity and effector molecule expression of the CD4⁺ CD25⁺ Foxp3^- thus require further analyses.

Immunotherapeutic Transport Oncophysics: Space, Time, and Immune Activation in Cancer

Immuno-oncology has gained momentum thanks to the success of strategies aimed at enhancing immune-mediated antitumor response. The field of immunotherapeutic transport oncophysics investigates the physical processes that drive cancer immunotherapies. This review discusses three main aspects that determine the outcome of an immunotherapy-based treatment from a physical point of view; (i) space, the distribution of cancer and immune cells within tumor masses, (ii) time, the temporal dynamic of immune response against tumors, and (iii) activity, the ability of immune cell populations to suppress cancer. Upon introducing these topics with examples from the literature, we investigate in detail two cases where the interplay between space, time, and activation variables determines immune response: nanodendritic cell vaccines and immunosuppression in ovarian cancer.