Notch-Inflammation Networks in Regulation of Breast Cancer Progression

Targeting Notch signaling pathways with natural bioactive compounds: a promising approach against cancer

Notch signaling pathway is activated abnormally in solid and hematological tumors, which perform essential functions in cell differentiation, survival, proliferation, and angiogenesis. The activation of Notch signaling and communication among Notch and other oncogenic pathways heighten malignancy aggressiveness. Thus, targeting Notch signaling offers opportunities for improved survival and reduced disease incidence. Already, most attention has been given to its role in the cancer cells. Recent research shows that natural bioactive compounds can change signaling molecules that are linked to or interact with the Notch pathways. This suggests that there may be a link between Notch activation and the growth of tumors. Here, we sum up the natural bioactive compounds that possess inhibitory effects on human cancers by impeding the Notch pathway and preventing Notch crosstalk with other oncogenic pathways, which provoke further study of these natural products to derive rational therapeutic regimens for the treatment of cancer and develop novel anticancer drugs. This review revealed Notch as a highly challenging but promising target in oncology.

Bruceine D suppresses CAF-promoted TNBC metastasis under TNF-α stimulation by inhibiting Notch1-Jagged1/NF-κB(p65) signaling

BACKGROUND

Triple-negative breast cancer (TNBC) has a poor prognosis because of its high degree of malignancy and the lack of effective treatment options. Cancer-associated fibroblasts (CAFs) comprise the most abundant stromal cells in the tumor microenvironment (TME), leading to functional impairments and facilitating tumor metastasis. Excessive TNF-α further promotes cross-talk between different cells in TME. Therefore, there is an urgent need to develop more effective therapies and potential drugs that target the key factors that promote TNBC metastasis.

PURPOSE

The study aimed to evaluate the efficacy of Bruceine D, an active compound derived from the Chinese herb Brucea javanica, in inhibiting metastasis and elucidate the underlying mechanism of action in TNBC.

METHODS

In vitro, the clonogenic and the Transwell assays were used to assess the effects of Bruceine D on the proliferation, migration and invasion abilities of co-cultured CAFs and MDA-MB-231 (4T1) cells under TNF-α stimulation. TNF-α, IL-6, CXCL12, TGF-β1, and MMP9 levels in the supernatant of co-cultured cells were determined using ELISA. Western blotting was utilized to detect the expression levels of proteins related to the Notch1-Jagged1/NF-κB(p65) pathway. In vivo, the anti-tumor growth and anti-metastatic effectiveness of Bruceine D was evaluated by determining tumor weight, number of metastatic lesions, and pathological changes in the tumor and lung/liver tissues. The inhibitory effect of Bruceine D on α-SMA+ CAFs activation and CAF-medicated extracellular matrix remodeling was accessed using immunohistochemistry, immunofluorescence, and Masson and Sirius Red staining. The expression levels of Notch1, Jagged1 and p-NF-κB(p65) proteins in the primary tumors were measured by immunohistochemistry and western blotting.

RESULTS

In vitro, Bruceine D significantly inhibited the migration and invasion of co-cultured CAFs and MDA-MB-231 (4T1) cells under TNF-α stimulation, reduced the expression of tumor-promoting and matrix-remodeling cytokines secreted by CAFs, and hindered the mutual activation of Notch1-Jagged1 and NF-κB(p65). In vivo, Bruceine D significantly suppressed tumor growth and the formation of lung and liver metastases by decreasing TNF-α stimulated α-SMA+ CAFs activation, collagen fibers, MMPs production, and inhibited Notch1-Jagged1/NF-κB(p65) signaling in TNBC-bearing mice.

CONCLUSION

Bruceine D effectively weakened the "tumor-CAF-inflammation" network by inhibiting the mutual activation of Notch1-Jagged1 and NF-κB(p65) and thereby suppressed TNBC metastasis. This study first explored that Bruceine D disrupted the cross-talk between CAFs and tumor cells under TNF-α stimulation to inhibit the metastasis of TNBC, and highlighted the potential of Bruceine D as therapeutic agent for suppressing tumor metastasis.

A unique cell population expressing the Epithelial-Mesenchymal Transition-transcription factor Snail moderates microglial and astrocyte injury responses

Insults to the central nervous system (CNS) elicit common glial responses including microglial activation evidenced by functional, morphological, and phenotypic changes, as well as astrocyte reactions including hypertrophy, altered process orientation, and changes in gene expression and function. However, the cellular and molecular mechanisms that initiate and modulate such glial response are less well-defined. Here we show that an adult cortical lesion generates a population of ultrastructurally unique microglial-like cells that express Epithelial-Mesenchymal Transcription factors including Snail. Knockdown of Snail with antisense oligonucleotides results in a postinjury increase in activated microglial cells, elevation in astrocyte reactivity with increased expression of C3 and phagocytosis, disruption of astrocyte junctions and neurovascular structure, increases in neuronal cell death, and reduction in cortical synapses. These changes were associated with alterations in pro-inflammatory cytokine expression. By contrast, overexpression of Snail through microglia-targeted an adeno-associated virus (AAV) improved many of the injury characteristics. Together, our results suggest that the coordination of glial responses to CNS injury is partly mediated by epithelial-mesenchymal transition-factors (EMT-Fsl).

An inflammatory-related genes signature based model for prognosis prediction in breast cancer

Background

Breast cancer has become the most common malignant tumor in the world. It is vital to discover novel prognostic biomarkers despite the fact that the majority of breast cancer patients have a good prognosis because of the high heterogeneity of breast cancer, which causes the disparity in prognosis. Recently, inflammatory-related genes have been proven to play an important role in the development and progression of breast cancer, so we set out to investigate the predictive usefulness of inflammatory-related genes in breast malignancies.

Methods

We assessed the connection between Inflammatory-Related Genes (IRGs) and breast cancer by studying the TCGA database. Following differential and univariate Cox regression analysis, prognosis-related differentially expressed inflammatory genes were estimated. The prognostic model was constructed through the Least Absolute Shrinkage and Selector Operation (LASSO) regression based on the IRGs. The accuracy of the prognostic model was then evaluated using the Kaplan-Meier and Receiver Operating Characteristic (ROC) curves. The nomogram model was established to predict the survival rate of breast cancer patients clinically. Based on the prognostic expression, we also looked at immune cell infiltration and the function of immune-related pathways. The CellMiner database was used to research drug sensitivity.

Results

In this study, 7 IRGs were selected to construct a prognostic risk model. Further research revealed a negative relationship between the risk score and the prognosis of breast cancer patients. The ROC curve proved the accuracy of the prognostic model, and the nomogram accurately predicted survival rate. The scores of tumor-infiltrating immune cells and immune-related pathways were utilized to calculate the differences between the low- and high-risk groups, and then explored the relationship between drug susceptibility and the genes that were included in the model.

Conclusion

These findings contributed to a better understanding of the function of inflammatory-related genes in breast cancer, and the prognostic risk model provides a potentially promising prognostic strategy for breast cancer.

Effect of PCSK9 on atherosclerotic cardiovascular diseases and its mechanisms: Focus on immune regulation

Atherosclerosis is a basic pathological characteristic of many cardiovascular diseases, and if not effectively treated, patients with such disease may progress to atherosclerotic cardiovascular diseases (ASCVDs) and even heart failure. The level of plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) is significantly higher in patients with ASCVDs than in the healthy population, suggesting that it may be a promising new target for the treatment of ASCVDs. PCSK9 produced by the liver and released into circulation inhibits the clearance of plasma low-density lipoprotein-cholesterol (LDL-C), mainly by downregulating the level of LDL-C receptor (LDLR) on the surface of hepatocytes, leading to upregulated LDL-C in plasma. Numerous studies have revealed that PCSK9 may cause poor prognosis of ASCVDs by activating the inflammatory response and promoting the process of thrombosis and cell death independent of its lipid-regulatory function, yet the underlying mechanisms still need to be further clarified. In patients with ASCVDs who are intolerant to statins or whose plasma LDL-C levels fail to descend to the target value after treatment with high-dose statins, PCSK9 inhibitors often improve their clinical outcomes. Here, we summarize the biological characteristics and functional mechanisms of PCSK9, highlighting its immunoregulatory function. We also discuss the effects of PCSK9 on common ASCVDs.

Regulation of Notch Signaling Pathway to Innate Lymphoid Cells in Patients with Acute Myocardial Infarction

The Notch signaling pathway is an important regulator in fate decisions and immune responses of innate lymphoid cells (ILCs). However, the function of Notch signaling in ILCs in acute coronary syndrome is still not fully elucidated. Thirty-one unstable angina pectoris (UAP) patients, 21 acute myocardial infarction (AMI) patients, and 20 controls were included in this study. Peripheral blood mononuclear cells (PBMCs) were isolated. The mRNA expression levels of Notch receptors and ligands were measured by real-time PCR, while ILC subsets were measured by flow cytometry. Lin^- cells were purified and stimulated with γ-secretase inhibitor (GSI). ILC subsets, transcription factors, and secreted cytokines were assessed. Notch receptor and ligand mRNA levels were elevated in PBMCs and peripheral lin^- cells from AMI patients. There was no significant difference in total lin^-CD45⁺CD161⁺CD127⁺ ILC frequency among three groups. The CRTH2^-CD117^- ILC1 subset was down-regulated, while the CRTH2⁺ ILC2 subset was up-regulated in AMI patients. The CRTH2^-CD117⁺ ILC3 subpopulation was comparable among the three groups. ILC1% was negatively correlated with Notch1 and Notch2 in AMI patients. Inhibition of Notch signaling pathway by GSI induced elevations in ILC1 frequency, T-bet mRNA expression, and interferon-γ secretion and reduced ILC2 frequency, GATA3 mRNA levels, and interleukin-5/interleukin-13 production by lin^- cells from AMI patients. The current data indicated that activation of Notch signaling pathway might contribute to ILC1-to-ILC2 shift in peripheral blood in AMI patients.

Comprehensive evaluation of breast cancer immunotherapy and tumor microenvironment characterization based on interleukin genes-related risk model

Breast cancer (BRCA) is the most prevalent malignancy and the leading cause of death in women. Interleukin (IL) genes are critical in tumor initiation and control. Nevertheless, the prognosis value of the IL in BRCA remains unclear. We collected data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), and 94 IL genes were identified from GeneCard. Based on the random forest (RF), least absolute shrinkage and selection operator (LASSO) analysis, and multivariate Cox regression analysis, we constructed an IL signature. GSE22219, GSE25065, and GSE21653 were derived as validation sets. The expression differences in the tumor microenvironment (TME), immunotherapy, and chemosensitivity of BRCA between the high- and low-risk groups were evaluated. Overall, 21 IL genes were selected to construct an IL risk model, of which IL18BP, IL17D, and IL23A were the first time identified as prognostic genes in BRCA. IL score could distinguish BRCA patients with inferior outcomes, and AUC of it was 0.70, 0.76, and 0.72 for 1-,3- and 5- years, respectively, which was also verified in GSE22219, GSE25065, and GSE21653 cohorts. Meanwhile, compared to luminal A and luminal B, HER2-positive and TNBC had significantly higher IL score. Besides, the high-risk group had a significantly higher prevalence of TP53 and TTN but a lower prevalence of PIK3CA, as well as higher tumor mutation burden (TMB) and neoantigen level. High- and low-risk groups exhibited notable differences in immunomodulators and tumor infiltrates immune cells (TIICs), and the high-risk group had significantly lower Tumor Immune Dysfunction and Exclusion (TIDE) score. Additionally, the high-risk group has more responders to immune or anti-HER2 combination therapy, whereas the low-risk group has higher sensitivity to docetaxel and paclitaxel. Consequently, we constructed a reliable risk model based on the IL genes, which can provide more information on both the risk stratification and personalizing management strategies for BRCA.

Notch Signaling in Breast Tumor Microenvironment as Mediator of Drug Resistance

Notch signaling dysregulation encourages breast cancer progression through different mechanisms such as stem cell maintenance, cell proliferation and migration/invasion. Furthermore, Notch is a crucial driver regulating juxtracrine and paracrine communications between tumor and stroma. The complex interplay between the abnormal Notch pathway orchestrating the activation of other signals and cellular heterogeneity contribute towards remodeling of the tumor microenvironment. These changes, together with tumor evolution and treatment pressure, drive breast cancer drug resistance. Preclinical studies have shown that targeting the Notch pathway can prevent or reverse resistance, reducing or eliminating breast cancer stem cells. In the present review, we will summarize the current scientific evidence that highlights the involvement of Notch activation within the breast tumor microenvironment, angiogenesis, extracellular matrix remodeling, and tumor/stroma/immune system interplay and its involvement in mechanisms of therapy resistance.

The Emerging Role of Cyclin-Dependent Kinase Inhibitors in Treating Diet-Induced Obesity: New Opportunities for Breast and Ovarian Cancers?

Overweight and obesity constitute the most impactful lifestyle-dependent risk factors for cancer and have been tightly linked to a higher number of tumor-related deaths nowadays. The excessive accumulation of energy can lead to an imbalance in the level of essential cellular biomolecules that may result in inflammation and cell-cycle dysregulation. Nutritional strategies and phytochemicals are gaining interest in the management of obesity-related cancers, with several ongoing and completed clinical studies that support their effectiveness. At the same time, cyclin-dependent kinases (CDKs) are becoming an important target in breast and ovarian cancer treatment, with various FDA-approved CDK4/6 inhibitors that have recently received more attention for their potential role in diet-induced obesity (DIO). Here we provide an overview of the most recent studies involving nutraceuticals and other dietary strategies affecting cell-cycle pathways, which might impact the management of breast and ovarian cancers, as well as the repurposing of already commercialized chemotherapeutic options to treat DIO.

Novel antitumor activity of the combined treatment of galloylquinic acids from Copaifera lucens and doxorubicin in solid Ehrlich carcinoma-bearing mice via the modulation of the Notch signaling pathway

AIMS

This study aims to investigate the potential synergistic effect of the combined treatment of galloylquinic acids compounds from Copaifera lucens with doxorubicin via the modulation of the Notch pathway in Ehrlich carcinoma-bearing mice model.

MAIN METHODS

The solid tumor model was induced in mice by s.c. injection of Ehrlich cancerous cells in the right hind limb. Sixty mice were allocated into five different groups which included treated groups with galloylquinic acids compounds, doxorubicin and their combination. Normal and tumor control groups were also used. Different biological samples were collected to measure the levels of Notch1, Hes1, Jagged1, TNF-α, IL-6, and VEGF. Histopathological and immunohistochemical examinations of tumor tissues using specific anti-NF-kβ and anti-cyclin D1 antibodies were also performed.

KEY FINDINGS

Our results showed that the combined treatment of galloylquinic acids compounds with doxorubicin significantly inhibited Notch1, Hes1, Jagged1, TNF-α, IL-6, VEGF, NF-kβ, and cyclin D1 activities.

SIGNIFICANCE

Galloylquinic acids compounds exhibited promising synergistic chemotherapeutic and oncostatic effects and promoted the chemosensitivity of doxorubicin, mainly by inhibiting the Notch signaling pathway and its downstream effectors. These compounds may be considered in cancer therapy exhibiting improved efficacy and reduced side effects of chemotherapeutic agents.

The effects of periodontitis associated microbiota on the development of oral squamous cell carcinoma

Epidemiological data have shown that periodontal bacterial infection, periodontitis, and oral squamous cell carcinoma have close relationship on the disease progress and risk. However, the specific role of periodontal microbes and their mechanism in the development of oral squamous cell carcinoma is not yet clear. In our previous work, metagenomic Illumina Mi-seq analysis was used to identify tstructure and abundance of periodontital microbiome. Accoding to the results, we used Porphyromonas.spp. and Fusobacterium.spp. as the periodontitis positive microbiota; Neisseria.spp and Corynebacterium.spp as periodontitis negative microbiota (their average relative abundance were >5%). These representative strains of the above genus were used to infect OSCC cells to explore their effect on tumor cell biology behavior, and detect the expression level of the gene in related to inflammation, migration, invasion and cell cycle. We find that periodontitis positive correlated microbiota had a promoting effect on the development of oral squamous cell carcinoma in vitro by regulating mRNA and protein expression of IL-6, IL-8, MMP-9 and Cyclin-D1. Periodontitis negative correlated microbiota had suppression effect on the development of oral squamous cell carcinoma in vitro analysis.

Persistent Inflammatory Stimulation Drives the Conversion of MSCs to Inflammatory CAFs That Promote Pro-Metastatic Characteristics in Breast Cancer Cells

The pro-inflammatory cytokines tumor necrosis factor α (TNFα) and interleukin 1β (IL-1β) are expressed simultaneously and have tumor-promoting roles in breast cancer. In parallel, mesenchymal stem cells (MSCs) undergo conversion at the tumor site to cancer-associated fibroblasts (CAFs), which are generally connected to enhanced tumor progression. Here, we determined the impact of consistent inflammatory stimulation on stromal cell plasticity. MSCs that were persistently stimulated by TNFα + IL-1β (generally 14-18 days) gained a CAF-like morphology, accompanied by prominent changes in gene expression, including in stroma/fibroblast-related genes. These CAF-like cells expressed elevated levels of vimentin and fibroblast activation protein (FAP) and demonstrated significantly increased abilities to contract collagen gels. Moreover, they gained the phenotype of inflammatory CAFs, as indicated by the reduced expression of α smooth muscle actin (αSMA), increased proliferation, and elevated expression of inflammatory genes and proteins, primarily inflammatory chemokines. These inflammatory CAFs released factors that enhanced tumor cell dispersion, scattering, and migration; the inflammatory CAF-derived factors elevated cancer cell migration by stimulating the chemokine receptors CCR2, CCR5, and CXCR1/2 and Ras-activating receptors, expressed by the cancer cells. Together, these novel findings demonstrate that chronic inflammation can induce MSC-to-CAF conversion, leading to the generation of tumor-promoting inflammatory CAFs.