Aberrant WNT/CTNNB1 Signaling as a Therapeutic Target in Human Breast Cancer: Weighing the Evidence

Network pharmacology-integrated molecular modeling analysis of Aquilaria malaccensis L. (agarwood) essential oil phytocompounds

A network pharmacology approach was used to construct comprehensive pharmacological networks, elucidating the interactions between agarwood compounds and key biological targets associated with cancer pathways. We have employed a combination of network pharmacology, molecular docking and molecular dynamics to unravel agarwood plants' active components and potential mechanisms. Reported 23 molecules were collected from the agarwood plants and considered to identify molecular targets. Further, we identified ten potent targets related to cancer through network pharmacology analysis. The key targets include EGFR, JUN, TP53, SRC, MAPK3, ACTB, GAPDH, AKT1, MYC and CTNNB1. The biological processes include the negative regulation of fibroblast proliferation, metabolic, oxidative, and more. Subsequently, molecular docking results have indicated that 7-isopropenyl-1, 4a-dimethyl-4, 4a, 5,6,7,8-hexahydro-3 H-naphthalen-2-one showed an excellent binding affinity for all ten targets. This is the first study; we employed a novel integrated approach that combines network pharmacology, molecular docking and molecular dynamics simulation (MDS). The GO and KEGG, pathway enrichment analyses, shed light on biological processes relevant to cancer treatment. Moreover, molecular docking studies results indicated that the molecule 7-isopropenyl-1,4a-dimethyl-4,4a,5,6,7,8-hexahydro-3H-naphthalen-2-one exhibited strong binding affinity among all ten cancer targets, with a docking score ranging from - 9.9 to - 6.7 kcal/mol and found to have hydrogen bond interaction with Lys168, Ser322, Thr336 and Ala946 residues. MDS sheds light on the stability of their binding, the longevity of their interactions, and their overall effect on the enzyme's active site throughout the simulation. The current work signifies the initial report using bioinformatics approaches to assess the anticancer properties of compounds derived from the agarwood plant.

Comprehensive utilization of in silico approach and in vitro experiment to unveil the molecular mechanisms of mono (2-ethylhexyl) phthalate-induced lung adenocarcinoma

Mono (2-ethylhexyl) phthalate (MEHP), the main bioactive metabolite of commonly used plasticizer Di (2-ethylhexyl) phthalate, has received increasing attention due to its carcinogenic toxicity. This study aims to systematically explore the molecular mechanisms underlying MEHP-induced lung adenocarcinoma (LUAD). Firstly, network toxicology was employed to construct the interaction network of MEHP-targeted LUAD-related proteins and identify core proteins. Subsequently, functional analyses were used to determine the key pathways of these proteins enriched. Next, expression and survival analyses of multiple public datasets were conducted to emphasize the importance of core genes, and an optimized prognostic model was constructed based on independent prognostic genes to explore the relationship of gene risk with immune infiltration and immunotherapy. Ultimately, molecular docking and dynamics simulation were used to predict the binding modes and affinities of MEHP with core proteins, and surface plasmon resonance experiments were utilized to further validate their direct interactions. The findings demonstrated that MEHP targets 167 LUAD-related proteins, including 28 core target proteins. These proteins form the critical networks that regulate cancer and immune-associated pathways to induce the occurrence and development of LUAD, and further coordinate patient prognosis and treatment by altering the immune microenvironment. Most importantly, their direct interactions (especially PTGS2) lay the structural foundation of MEHP regulating core proteins, greatly supporting its LUAD toxicity. In conclusion, this study introduces a novel approach for evaluating the safety of plasticizers and elucidates the molecular mechanisms behind MEHP-induced LUAD, thus offering new and effective targets and strategies for cancer prevention and treatment.

C/EBPβ deletion in macrophages impairs mammary gland alveolar budding during the estrous cycle

Macrophages have important roles in mammary gland development and tissue homeostasis, but the specific mechanisms that regulate macrophage function need further elucidation. We have identified C/EBPβ as an important transcription factor expressed by multiple macrophage populations in the normal mammary gland. Mammary glands from mice with C/EBPβ-deficient macrophages (Cebpb ΔM) show a significant decrease in alveolar budding during the diestrus stage of the reproductive cycle, whereas branching morphogenesis remains unchanged. Defects in alveolar budding were found to be the result of both systemic hormones and local macrophage-directed signals. RNA sequencing shows significant changes in PR-responsive genes and alterations in the Wnt landscape of mammary epithelial cells of Cebpb ΔM mice, which regulate stem cell expansion during diestrus. Cebpb ΔM macrophages demonstrate a shift from a pro-inflammatory to a tissue-reparative phenotype, and exhibit increased phagocytic capacity as compared to WT. Finally, Cebpb ΔM macrophages down-regulate Notch2 and Notch3, which normally promote stem cell expansion during alveolar budding. These results suggest that C/EBPβ is an important macrophage factor that facilitates macrophage-epithelial crosstalk during a key stage of mammary gland tissue homeostasis.

Canonical WNT/β-catenin signaling upregulates aerobic glycolysis in diverse cancer types

Despite many efforts, a comprehensive understanding and clarification of the intricate connections within cancer cell metabolism remain elusive. This might pertain to intracellular dynamics and the complex interplay between cancer cells, and cells with the tumor stroma. Almost a century ago, Otto Warburg found that cancer cells exhibit a glycolytic phenotype, which continues to be a subject of thorough investigation. Past and ongoing investigations have demonstrated intricate mechanisms by which tumors modulate their functionality by utilizing extracellular glucose as a substrate, thereby sustaining the essential proliferation of cancer cells. This concept of "aerobic glycolysis," where cancer cells (even in the presence of enough oxygen) metabolize glucose to produce lactate plays a critical role in cancer progression and is regulated by various signaling pathways. Recent research has revealed that the canonical wingless-related integrated site (WNT) pathway promotes aerobic glycolysis, directly and indirectly, thereby influencing cancer development and progression. The present review seeks to gather knowledge about how the WNT/β-catenin pathway influences aerobic glycolysis, referring to relevant studies in different types of cancer. Furthermore, we propose the concept of impeding the glycolytic phenotype of tumors by employing specific inhibitors that target WNT/β-catenin signaling.

Study of the mechanism by which Xiaoyan decoction combined with E7449 regulates tumorigenesis in lung adenocarcinoma

TNKS is a new target for the treatment of lung adenocarcinoma, the synergistic effects of the TCM compound Xiaoyan decoction and the TNKS inhibitor E7449 in the intervention on TNKS were investigated, and the possible underlying mechanisms involved were clarified. Immunohistochemistry was used to analyse TNKS expression in tumour tissues. The impact of targeting TNKS on cell growth, invasion, apoptosis, key genes and signalling pathways was investigated in tumour cells by Western blotting, rescue experiments, colony formation assays, flow cytometry and label-free experiments. Tumour xenografts with A549 cells were then transplanted for in vivo study. We found that TNKS high expression was closely related to the advanced tumour stage and tumour size in lung adenocarcinom. After TNKS was knocked down in vitro, the growth, proliferation, migration and invasion were markedly reduced in A549 and H1975 cells. We subsequently applied the Xiaoyan decoction and TNKS inhibitors to intervene in lung adenocarcinoma. Xiaoyan decoction and E7449 suppressed TNKS expression and inhibited adenocarcinoma cell proliferation, migration, invasion and apoptosis in vitro. Proteomic analysis revealed that E7449 treatment may be most closely associated with the classic Wnt/β-catenin pathway, whereas Xiaoyan decoction treatment may be related to the WNT/PLAN pathway. Xenograft studies confirmed that E7449 or Xiaoyan decoction inhibited lung tumour growth in vivo and attenuated the Wnt signalling pathway in adenocarcinoma. These findings suggest that TNKS is a novel therapeutic target. TCM preparations and small molecule inhibitors are expected to constitute an effective combination strategy.

Network-based approach elucidates critical genes in BRCA subtypes and chemotherapy response in triple negative breast cancer

Breast cancers (BRCA) exhibit substantial transcriptional heterogeneity, posing a significant clinical challenge. The global transcriptional changes in a disease context, however, are likely mediated by few key genes which reflect disease etiology better than the differentially expressed genes (DEGs). We apply our network-based tool PathExt to 1,059 BRCA tumors across 4 subtypes to identify key mediator genes in each subtype. Compared to conventional differential expression analysis, PathExt-identified genes exhibit greater concordance across tumors, revealing shared and subtype-specific biological processes; better recapitulate BRCA-associated genes in multiple benchmarks, and are more essential in BRCA subtype-specific cell lines. Single-cell transcriptomic analysis reveals a subtype-specific distribution of PathExt-identified genes in multiple cell types from the tumor microenvironment. Application of PathExt to a TNBC chemotherapy response dataset identified subtype-specific key genes and biological processes associated with resistance. We described putative drugs that target key genes potentially mediating drug resistance.

Evaluating the Role of Neddylation Modifications in Kidney Renal Clear Cell Carcinoma: An Integrated Approach Using Bioinformatics, MLN4924 Dosing Experiments, and RNA Sequencing

BACKGROUND

Neddylation, a post-translational modification process, plays a crucial role in various human neoplasms. However, its connection with kidney renal clear cell carcinoma (KIRC) remains under-researched.

METHODS

We validated the Gene Set Cancer Analysis Lite (GSCALite) platform against The Cancer Genome Atlas (TCGA) database, analyzing 33 cancer types and their link with 17 neddylation-related genes. This included examining copy number variations (CNVs), single nucleotide variations (SNVs), mRNA expression, cellular pathway involvement, and methylation. Using Gene Set Variation Analysis (GSVA), we categorized these genes into three clusters and examined their impact on KIRC patient prognosis, drug responses, immune infiltration, and oncogenic pathways. Afterward, our objective is to identify genes that exhibit overexpression in KIRC and are associated with an adverse prognosis. After pinpointing the specific target gene, we used the specific inhibitor MLN4924 to inhibit the neddylation pathway to conduct RNA sequencing and related in vitro experiments to verify and study the specificity and potential mechanisms related to the target. This approach is geared towards enhancing our understanding of the prognostic importance of neddylation modification in KIRC.

RESULTS

We identified significant CNV, SNV, and methylation events in neddylation-related genes across various cancers, with notably higher expression levels observed in KIRC. Cluster analysis revealed a potential trade-off in the interactions among neddylation-related genes, where both high and low levels of gene expression are linked to adverse prognoses. This association is particularly pronounced concerning lymph node involvement, T stage classification, and Fustat score. Simultaneously, our research discovered that PSMB10 exhibits overexpression in KIRC when compared to normal tissues, negatively impacting patient prognosis. Through RNA sequencing and in vitro assays, we confirmed that the inhibition of neddylation modification could play a role in the regulation of various signaling pathways, thereby influencing the prognosis of KIRC. Moreover, our results underscore PSMB10 as a viable target for therapeutic intervention in KIRC, opening up novel pathways for the development of targeted treatment strategies.

CONCLUSION

This study underscores the regulatory function and potential mechanism of neddylation modification on the phenotype of KIRC, identifying PSMB10 as a key regulatory target with a significant role in influencing the prognosis of KIRC.

BMP Stimulation Differentially Affects Phosphorylation and Protein Stability of β-Catenin in Breast Cancer Cell Lines

Increased expression and nuclear translocation of β-CATENIN is frequently observed in breast cancer, and it correlates with poor prognosis. Current treatment strategies targeting β-CATENIN are not as efficient as desired. Therefore, detailed understanding of β-CATENIN regulation is crucial. Bone morphogenetic proteins (BMP) and Wingless/Integrated (WNT) pathway crosstalk is well-studied for many cancer types including colorectal cancer, whereas it is still poorly understood for breast cancer. Analysis of breast cancer patient data revealed that BMP2 and BMP6 were significantly downregulated in tumors. Since mutation frequency in genes enhancing β-CATENIN protein stability is relatively low in breast cancer, we aimed to investigate whether decreased BMP ligand expression could contribute to a high protein level of β-CATENIN in breast cancer cells. We demonstrated that downstream of BMP stimulation, SMAD4 is required to reduce β-CATENIN protein stability through the phosphorylation in MCF7 and T47D cells. Consequently, BMP stimulation reduces β-CATENIN levels and prevents its nuclear translocation and target gene expression in MCF7 cells. Conversely, BMP stimulation has no effect on β-CATENIN phosphorylation or stability in MDA-MB-231 and MDA-MB-468 cells. Likewise, SMAD4 modulation does not alter the response of those cells, indicating that SMAD4 alone is insufficient for BMP-induced β-CATENIN phosphorylation. While our data suggest that considering BMP activity may serve as a prognostic marker for understanding β-CATENIN accumulation risk, further investigation is needed to elucidate the differential responsiveness of breast cancer cell lines.

Cancer invasion and anaerobic bacteria: new insights into mechanisms

There is growing evidence that altered microbiota abundance of a range of specific anaerobic bacteria are associated with cancer, including Peptoniphilus spp., Porphyromonas spp., Fusobacterium spp., Fenollaria spp., Prevotella spp., Sneathia spp., Veillonella spp. and Anaerococcus spp. linked to multiple cancer types. In this review we explore these pathogenic associations. The mechanisms by which bacteria are known or predicted to interact with human cells are reviewed and we present an overview of the interlinked mechanisms and hypotheses of how multiple intracellular anaerobic bacterial pathogens may act together to cause host cell and tissue microenvironment changes associated with carcinogenesis and cancer cell invasion. These include combined effects on changes in cell signalling, DNA damage, cellular metabolism and immune evasion. Strategies for early detection and eradication of anaerobic cancer-associated bacterial pathogens that may prevent cancer progression are proposed.

System biology mediated assessment of molecular mechanism for sinapic acid against breast cancer: via network pharmacology and molecular dynamic simulation

Sinapic acid is a hydroxycinnamic acid widespread in the plant kingdom, known to be a potent anti-oxidant used for the treatment of cancer, infections, oxidative stress, and inflammation. However, the mode of action for its chemotherapeutic properties has yet not been unleashed. Hence, we aimed to identify potential targets to propose a possible molecular mechanism for sinapic acid against breast cancer. We utilized multiple system biology tools and databases like DisGeNET, DIGEP-Pred, Cytoscape, STRING, AutoDock 4.2, AutoDock vina, Schrodinger, and gromacs to predict a probable molecular mechanism for sinapic acid against breast cancer. Targets for the disease breast cancer, were identified via DisGeNET database which were further matched with proteins predicted to be modulated by sinapic acid. In addition, KEGG pathway analysis was used to identify pathways; a protein-pathway network was constructed via Cytoscape. Molecular docking was performed using three different algorithms followed by molecular dynamic simulations and MMPBSA analysis. Moreover, cluster analysis and gene ontology (GO) analysis were performed. A total of 6776 targets were identified for breast cancer; 95.38% of genes predicted to be modulated by sinapic acid were common with genes of breast cancer. The 'Pathways in cancer' was predicted to be modulated by most umber of proteins. Further, PRKCA, CASP8, and CTNNB1 were predicted to be the top 3 hub genes. In addition, molecular docking studies revealed CYP3A4, CYP1A1, and SIRT1 to be the lead proteins identified from AutoDock 4.2, AutoDock Vina, and Schrodinger suite Glide respectively. Molecular dynamic simulation and MMPBSA were performed for the complex of sinapic acid with above mentioned proteins which revealed a stable complex throughout simulation. The predictions revealed that the mechanism of sinapic acid in breast cancer may be due to regulation of multiple proteins like CTNNB1, PRKCA, CASP8, SIRT1, and cytochrome enzymes (CYP1A1 & CYP3A4); the majorly regulated pathway was predicted to be 'Pathways in cancer'. This indicates the rationale for sinapic acid to be used in the treatment of breast cancer. However, these are predictions and need to be validated and looked upon in-depth to confirm the exact mechanism of sinapic acid in the treatment of breast cancer; this is future scope as well as a drawback of the current study.

Multi-omics profiling reveals cellular pathways and functions regulated by ALDH1B1 in colon cancer cells

Colon cancer is the third leading cause of cancer death globally. Although early screenings and advances in treatments have reduced mortality since 1970, identification of novel targets for therapeutic intervention is needed to address tumor heterogeneity and recurrence. Previous work identified aldehyde dehydrogenase 1B1 (ALDH1B1) as a critical factor in colon tumorigenesis. To investigate further, we utilized a human colon adenocarcinoma cell line (SW480) in which the ALDH1B1 protein expression has been knocked down by 80% via shRNA. Through multi-omics (transcriptomics, proteomics, and untargeted metabolomics) analysis, we identified the impact of ALDH1B1 knocking down (KD) on molecular signatures in colon cancer cells. Suppression of ALDH1B1 expression resulted in 357 differentially expressed genes (DEGs), 191 differentially expressed proteins (DEPs) and 891 differentially altered metabolites (DAMs). Functional annotation and enrichment analyses revealed that: (1) DEGs were enriched in integrin-linked kinase (ILK) signaling and growth and development pathways; (2) DEPs were mainly involved in apoptosis signaling and cellular stress response pathways; and (3) DAMs were associated with biosynthesis, intercellular and second messenger signaling. Collectively, the present study provides new molecular information associated with the cellular functions of ALDH1B1, which helps to direct future investigation of colon cancer.

PTCH1 and CTNNB1 emerge as pivotal predictors of resistance to neoadjuvant chemotherapy in ER+/HER2- breast cancer

Introduction

Endeavors in the molecular characterization of breast cancer opened the doors to endocrine therapies in ER+/HER2- breast cancer, increasing response rates substantially. Despite that, taxane-based neoadjuvant chemotherapy is still a cornerstone for achieving breast-conserving surgery and complete tumor resection in locally advanced cancers with high recurrence risk. Nonetheless, the rate of chemoresistance is high, and deselecting patients who will not benefit from chemotherapy is a significant task to prevent futile toxicities. Several multigene assays are being used to guide decisions on chemotherapy. However, their development as prognostic assays but not predictive assays limits predictive strength, leading to discordant results. Moreover, high costs impediment their use in developing countries. For global health equity, robust predictors that can be cost-effectively incorporated into routine clinical management are essential.

Methods

In this study, we comprehensively analyzed 5 GEO datasets, 2 validation sets, and The Cancer Genome Atlas breast cancer data to identify predictors of resistance to taxane-based neoadjuvant therapy in ER+/HER2- breast cancer using efficient bioinformatics algorithms.

Results

Gene expression and gene set enrichment analysis of 5 GEO datasets revealed the upregulation of 63 genes and the enrichment of CTNNB1-related oncogenic signatures in non-responsive patients. We validated the upregulation and predictive strength of 18 genes associated with resistance in the validation cohort, all exhibiting higher predictive powers for residual disease and higher specificities for ER+/HER2- breast cancers compared to one of the benchmark multi-gene assays. Cox Proportional Hazards Regression in three different treatment arms (neoadjuvant chemotherapy, endocrine therapy, and no systemic treatment) in a second comprehensive validation cohort strengthened the significance of PTCH1 and CTNNB1 as key predictors, with hazard ratios over 1.5, and 1.6 respectively in the univariate and multivariate models.

Discussion

Our results strongly suggest that PTCH1 and CTNNB1 can be used as robust and cost-effective predictors in developing countries to guide decisions on chemotherapy in ER +/HER2- breast cancer patients with a high risk of recurrence. The dual function of PTCH1 as a multidrug efflux pump and a hedgehog receptor, and the active involvement of CTNNB1 in breast cancer strongly indicate that PTCH1 and CTNNB1 can be potential drug targets to overcome chemoresistance in ER +/HER2- breast cancer patients.

Integrated bioinformatics analyses identifying potential biomarkers for type 2 diabetes mellitus and breast cancer: In SIK1-ness and health

The bidirectional causal relationship between type 2 diabetes mellitus (T2DM) and breast cancer (BC) has been established by numerous epidemiological studies. However, the underlying molecular mechanisms are not yet fully understood. Identification of hub genes implicated in T2DM-BC molecular crosstalk may help elucidate on the causative mechanisms. For this, expression series GSE29231 (T2DM-adipose tissue), GSE70905 (BC- breast adenocarcinoma biopsies) and GSE150586 (diabetes and BC breast biopsies) were extracted from Gene Expression Omnibus (GEO) database, and analyzed to obtain differentially expressed genes (DEGs). The overlapping DEGs were determined using FunRich. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and Transcription Factor (TF) analyses were performed on EnrichR software and a protein-protein interaction (PPI) network was constructed using STRING software. The network was analyzed on Cytoscape to determine hub genes and Kaplan-Meier plots were obtained. A total of 94 overlapping DEGs were identified between T2DM and BC samples. These DEGs were mainly enriched for GO terms RNA polymerase II core promoter proximal region sequence and its DNA binding, and cAMP response element binding protein, and KEGG pathways including bladder cancer, thyroid cancer and PI3K-AKT signaling. Eight hub genes were identified: interleukin 6 (IL6), tumor protein 53 (TP53), interleukin 8 (CXCL8), MYC, matrix metalloproteinase 9 (MMP9), beta-catenin 1 (CTNNB1), nitric oxide synthase 3 (NOS3) and interleukin 1 beta (IL1β). MMP9 and MYC associated unfavorably with overall survival (OS) in breast cancer patients, IL6, TP53, IL1β and CTNNB1 associated favorably, whereas NOS3 did not show any correlation with OS. Salt inducible kinase 1 (SIK1) was identified as a significant key DEG for comorbid samples when compared with BC, also dysregulated in T2DM and BC samples (adjusted p <0.05). Furthermore, four of the significant hub genes identified, including IL6, CXCL8, IL1B and MYC were also differentially expressed for comorbid samples, however at p < 0.05. Our study identifies key genes including SIK1, for comorbid state and 8 hub genes that may be implicated in T2DM-BC crosstalk. However, limitations associated with the insilico nature of this study necessitates for subsequent validation in wet lab. Hence, further investigation is crucial to study the molecular mechanisms of action underlying these genes to fully explore their potential as diagnostic and prognostic biomarkers and therapeutic targets for T2DM-BC association.

R-spondin-3 promotes proliferation and invasion of breast cancer cells independently of Wnt signaling

We recently identified R-spondin-3 (RSPO3) as a novel driver of breast cancer associating with reduced patient survival, expanding its clinical value as potential therapeutic target that had been recognized mostly for colorectal cancer so far. (Pre)clinical studies exploring RSPO3 targeting in colorectal cancer approach this indirectly with Wnt inhibitors, or directly with anti-RSPO3 antibodies. Here, we address the clinical relevance of RSPO3 in breast cancer and provide insight in the oncogenic activities of RSPO3. Utilizing the RSPO3 breast cancer mouse model, we show that RSPO3 drives the aberrant expansion of luminal progenitor cells expressing cancer stem cell marker CD61, inducing proliferative, poorly differentiated and invasive tumors. Complementary studies with tumor organoids and human breast cancer cell lines demonstrate that RSPO3 consistently promotes the proliferation and invasion of breast cancer cells. Importantly, RSPO3 exerts these oncogenic effects independently of Wnt signaling, rejecting the therapeutic value of Wnt inhibitors in RSPO3-driven breast cancer. Instead, direct RSPO3 targeting effectively inhibited RSPO3-driven growth of breast cancer cells. Conclusively, our data indicate that RSPO3 exerts unfavorable oncogenic effects in breast cancer, enhancing proliferation and malignancy in a Wnt-independent fashion, proposing RSPO3 itself as a valuable therapeutic target in breast cancer.

Multiscale model of the different modes of cancer cell invasion

MOTIVATION

Mathematical models of biological processes altered in cancer are built using the knowledge of complex networks of signaling pathways, detailing the molecular regulations inside different cell types, such as tumor cells, immune and other stromal cells. If these models mainly focus on intracellular information, they often omit a description of the spatial organization among cells and their interactions, and with the tumoral microenvironment.

RESULTS

We present here a model of tumor cell invasion simulated with PhysiBoSS, a multiscale framework, which combines agent-based modeling and continuous time Markov processes applied on Boolean network models. With this model, we aim to study the different modes of cell migration and to predict means to block it by considering not only spatial information obtained from the agent-based simulation but also intracellular regulation obtained from the Boolean model.

Our multiscale model integrates the impact of gene mutations with the perturbation of the environmental conditions and allows the visualization of the results with 2D and 3D representations. The model successfully reproduces single and collective migration processes and is validated on published experiments on cell invasion. In silico experiments are suggested to search for possible targets that can block the more invasive tumoral phenotypes.

AVAILABILITY AND IMPLEMENTATION

https://github.com/sysbio-curie/Invasion_model_PhysiBoSS.

The overexpression of actin related protein 2/3 complex subunit 1B(ARPC1B) promotes the ovarian cancer progression via activation of the Wnt/β-catenin signaling pathway

Introduction

Ovarian cancer is one of the most fatal malignancies of the female reproductive system. The purpose of this study is to explore the mechanism of Actin Related Protein 2/3 Complex Subunit 1B(ARPC1B) in the progression of ovarian cancer.

Methods

The expressions and prognostic value of ARPC1B in ovarian cancer were identified using the GEPIA database and the Kaplan-Meier Plotter database. The expression of ARPC1B was manipulated to evaluate its impact on the malignant phenotypes of ovarian cancer. The cell proliferation ability was analyzed through CCK-8 assay and clone formation assay. The cell migration and invasion capacity was evaluated through wound healing assay and trans well assay. Mice xenografts were conducted to measure the effects of ARPC1B on tumor development in vivo.

Results

Our data suggested that ARPC1B was overexpressed in ovarian cancer, which was correlated with a poorer survival compared to low mRNA expression of ARPC1B in ovarian cancer patients. The overexpression of ARPC1B promoted cell proliferation, migration, and invasion of ovarian cancer cells. Conversely, the knockdown of ARPC1B resulted in the opposite effect. Additionally, ARPC1B expression could activate Wnt/β-catenin signaling pathway. The administration of the β-catenin inhibitor XAV-939 abolished the promotion of cell proliferation, migration, and invasion activities induced by ARPC1B overexpression in vitro.

Conclusions

ARPC1B was overexpressed in ovarian cancer and was correlated with poor prognosis. ARPC1B promoted ovarian cancer progression through activation of Wnt/β-catenin Signaling Pathway.

Profiling and targeting cancer stem cell signaling pathways for cancer therapeutics

Tumorigenic cancer stem cells (CSCs) represent a subpopulation of cells within the tumor that express genetic and phenotypic profiles and signaling pathways distinct from the other tumor cells. CSCs have eluded many conventional anti-oncogenic treatments, resulting in metastases and relapses of cancers. Effectively targeting CSCs' unique self-renewal and differentiation properties would be a breakthrough in cancer therapy. A better characterization of the CSCs' unique signaling mechanisms will improve our understanding of the pathology and treatment of cancer. In this paper, we will discuss CSC origin, followed by an in-depth review of CSC-associated signaling pathways. Particular emphasis is given on CSC signaling pathways' ligand-receptor engagement, upstream and downstream mechanisms, and associated genes, and molecules. Signaling pathways associated with regulation of CSC development stand as potential targets of CSC therapy, which include Wnt, TGFβ (transforming growth factor-β)/SMAD, Notch, JAK-STAT (Janus kinase-signal transducers and activators of transcription), Hedgehog (Hh), and vascular endothelial growth factor (VEGF). Lastly, we will also discuss milestone discoveries in CSC-based therapies, including pre-clinical and clinical studies featuring novel CSC signaling pathway cancer therapeutics. This review aims at generating innovative views on CSCs toward a better understanding of cancer pathology and treatment.

Network-based approach elucidates critical genes in BRCA subtypes and chemotherapy response in Triple Negative Breast Cancer

Breast cancers exhibit substantial transcriptional heterogeneity, posing a significant challenge to the prediction of treatment response and prognostication of outcomes. Especially, translation of TNBC subtypes to the clinic remains a work in progress, in part because of a lack of clear transcriptional signatures distinguishing the subtypes. Our recent network-based approach, PathExt, demonstrates that global transcriptional changes in a disease context are likely mediated by a small number of key genes, and these mediators may better reflect functional or translationally relevant heterogeneity. We apply PathExt to 1059 BRCA tumors and 112 healthy control samples across 4 subtypes to identify frequent, key-mediator genes in each BRCA subtype. Compared to conventional differential expression analysis, PathExt-identified genes (1) exhibit greater concordance across tumors, revealing shared as well as BRCA subtype-specific biological processes, (2) better recapitulate BRCA-associated genes in multiple benchmarks, and (3) exhibit greater dependency scores in BRCA subtype-specific cancer cell lines. Single cell transcriptomes of BRCA subtype tumors reveal a subtype-specific distribution of PathExt-identified genes in multiple cell types from the tumor microenvironment. Application of PathExt to a TNBC chemotherapy response dataset identified TNBC subtype-specific key genes and biological processes associated with resistance. We described putative drugs that target top novel genes potentially mediating drug resistance. Overall, PathExt applied to breast cancer refines previous views of gene expression heterogeneity and identifies potential mediators of TNBC subtypes, including potential therapeutic targets.

The chemokine monocyte chemoattractant protein-1/CCL2 is a promoter of breast cancer metastasis

Breast cancer is the most prevalent cancer worldwide, and metastasis is the leading cause of death in cancer patients. Human monocyte chemoattractant protein-1 (MCP-1/CCL2) was isolated from the culture supernatants of not only mitogen-activated peripheral blood mononuclear leukocytes but also malignant glioma cells based on its in vitro chemotactic activity toward human monocytes. MCP-1 was subsequently found to be identical to a previously described tumor cell-derived chemotactic factor thought to be responsible for the accumulation of tumor-associated macrophages (TAMs), and it became a candidate target of clinical intervention; however, the role of TAMs in cancer development was still controversial at the time of the discovery of MCP-1. The in vivo role of MCP-1 in cancer progression was first evaluated by examining human cancer tissues, including breast cancers. Positive correlations between the level of MCP-1 production in tumors and the degree of TAM infiltration and cancer progression were established. The contribution of MCP-1 to the growth of primary tumors and metastasis to the lung, bone, and brain was examined in mouse breast cancer models. The results of these studies strongly suggested that MCP-1 is a promoter of breast cancer metastasis to the lung and brain but not bone. Potential mechanisms of MCP-1 production in the breast cancer microenvironment have also been reported. In the present manuscript, we review studies in which the role of MCP-1 in breast cancer development and progression and the mechanisms of its production were examined and attempt to draw a consensus and discuss the potential use of MCP-1 as a biomarker for diagnosis.

p140Cap inhibits β-Catenin in the breast cancer stem cell compartment instructing a protective anti-tumor immune response

The p140Cap adaptor protein is a tumor suppressor in breast cancer associated with a favorable prognosis. Here we highlight a function of p140Cap in orchestrating local and systemic tumor-extrinsic events that eventually result in inhibition of the polymorphonuclear myeloid-derived suppressor cell function in creating an immunosuppressive tumor-promoting environment in the primary tumor, and premetastatic niches at distant sites. Integrative transcriptomic and preclinical studies unravel that p140Cap controls an epistatic axis where, through the upstream inhibition of β-Catenin, it restricts tumorigenicity and self-renewal of tumor-initiating cells limiting the release of the inflammatory cytokine G-CSF, required for polymorphonuclear myeloid-derived suppressor cells to exert their local and systemic tumor conducive function. Mechanistically, p140Cap inhibition of β-Catenin depends on its ability to localize in and stabilize the β-Catenin destruction complex, promoting enhanced β-Catenin inactivation. Clinical studies in women show that low p140Cap expression correlates with reduced presence of tumor-infiltrating lymphocytes and more aggressive tumor types in a large cohort of real-life female breast cancer patients, highlighting the potential of p140Cap as a biomarker for therapeutic intervention targeting the β-Catenin/ Tumor-initiating cells /G-CSF/ polymorphonuclear myeloid-derived suppressor cell axis to restore an efficient anti-tumor immune response.

Scope of Wnt signaling in the precise diagnosis and treatment of breast cancer

Malignant breast cancers are responsible for a growing number of deaths among women globally. The latest research has demonstrated that Wnt signaling is pivotal in this disease, regulating a safe microenvironment for the growth and proliferation of cancer cells {AuQ: Edit OK?}, sustained stemness, resistance to therapy, and aggregate formation. The three highly conserved {AuQ: Edit OK?} Wnt signaling pathways, Wnt-planar cell polarity (PCP), Wnt/β-catenin signaling and Wnt-Ca²⁺ signaling, assume various roles in the maintenance and amelioration of breast cancer. In this review, we examine ongoing studies on the Wnt signaling pathways and discuss how dysregulation of these pathways promotes breast cancers. We also look at how Wnt dysregulation could be exploited to foster new treatments for malignant breast cancers.

The roles of KLHL family members in human cancers

The Kelch-like (KLHL) family members consist of three domains: bric-a-brac, tramtrack, broad complex/poxvirus and zinc finger domain, BACK domain and Kelch domain, which combine and interact with Cullin3 to form an E3 ubiquitin ligase. Research has indicated that KLHL family members ubiquitinate target substrates to regulate physiological and pathological processes, including tumorigenesis and progression. KLHL19, a member of the KLHL family, is associated with tumorigenesis and drug resistance. However, the regulation and cross talks of other KLHL family members, which also play roles in cancer, are still unclear. Our review mainly explores studies concerning the roles of other KLHL family members in tumor-related regulation to provide novel insights into KLHL family members.

Histone H3 proline 16 hydroxylation regulates mammalian gene expression

Histone post-translational modifications (PTMs) are important for regulating various DNA-templated processes. Here, we report the existence of a histone PTM in mammalian cells, namely histone H3 with hydroxylation of proline at residue 16 (H3P16oh), which is catalyzed by the proline hydroxylase EGLN2. We show that H3P16oh enhances direct binding of KDM5A to its substrate, histone H3 with trimethylation at the fourth lysine residue (H3K4me3), resulting in enhanced chromatin recruitment of KDM5A and a corresponding decrease of H3K4me3 at target genes. Genome- and transcriptome-wide analyses show that the EGLN2-KDM5A axis regulates target gene expression in mammalian cells. Specifically, our data demonstrate repression of the WNT pathway negative regulator DKK1 through the EGLN2-H3P16oh-KDM5A pathway to promote WNT/β-catenin signaling in triple-negative breast cancer (TNBC). This study characterizes a regulatory mark in the histone code and reveals a role for H3P16oh in regulating mammalian gene expression.

LncRNA FAM83H-AS1 promotes the malignant progression of pancreatic ductal adenocarcinoma by stabilizing FAM83H mRNA to protect β-catenin from degradation

Background

Pancreatic ductal adenocarcinoma is prone to metastasis, resulting in short survival and low quality of life. LncRNAs are pivotal orchestrators that participate in various tumor progress. The underlying role and mechanism of lncRNA FAM83H-AS1 is still unknown in PDAC progression.

Methods

To address this issue, firstly, we profiled and analyzed the aberrant lncRNA expression in TCGA database and identified FAM83H-AS1 as the most effective one in promoting the migration of pancreatic cancer cells. Then, the expression levels of FAM83H-AS1 in patient’s serum, tumor tissues and PDAC cells were detected using RT-qPCR, and FAM83H-AS1 distribution in PDAC cells was determined by performing FISH and RT-qPCR. Next, a series of in vivo and in vitro functional assays were conducted to elucidate the role of FAM83H-AS1 in cell growth and metastasis in PDAC. The regulatory relationship between FAM83H-AS1 and FAM83H (the homologous gene of FAM83H-AS1) was verified by performing protein and RNA degradation assays respectively. Co-IP assays were performed to explore the potential regulatory mechanism of FAM83H to β-catenin. Rescue assays were performed to validate the regulation of the FAM83H-AS1/FAM83H/β-catenin axis in PDAC progression.

Results

FAM83H-AS1 was highly expressed in the tumor tissues and serum of patients with PDAC, and was correlated with shorter survival. FAM83H-AS1 significantly promoted the proliferation, invasion and metastasis of PDAC cells, by protecting FAM83H mRNA from degradation. Importantly, FAM83H protein manifested the similar malignant functions as that of FAM83H-AS1 in PDAC cells, and could bind to β-catenin. Specifically, FAM83H could decrease the ubiquitylation of β-catenin, and accordingly activated the effector genes of Wnt/β-catenin signaling.

Conclusions

Collectively, FAM83H-AS1 could promote FAM83H expression by stabilizing its mRNA, allowing FAM83H to decrease the ubiquitylation of β-catenin, thus resulted in an amplified FAM83H-AS1/FAM83H/β-catenin signal axis to promote PDAC progression. FAM83H-AS1 might be a novel prognostic and therapeutic target for combating PDAC.

Anti-cancer therapeutic strategies based on HGF/MET, EpCAM, and tumor-stromal cross talk

As an intelligent disease, tumors apply several pathways to evade the immune system. It can use alternative routes to bypass intracellular signaling pathways, such as nuclear factor-κB (NF-κB), Wnt, and mitogen-activated protein (MAP)/phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR). Therefore, these mechanisms lead to therapeutic resistance in cancer. Also, these pathways play important roles in the proliferation, survival, migration, and invasion of cells. In most cancers, these signaling pathways are overactivated, caused by mutation, overexpression, etc. Since numerous molecules share these signaling pathways, the identification of key molecules is crucial to achieve favorable consequences in cancer therapy. One of the key molecules is the mesenchymal-epithelial transition factor (MET; c-Met) and its ligand hepatocyte growth factor (HGF). Another molecule is the epithelial cell adhesion molecule (EpCAM), which its binding is hemophilic. Although both of them are involved in many physiologic processes (especially in embryonic stages), in some cancers, they are overexpressed on epithelial cells. Since they share intracellular pathways, targeting them simultaneously may inhibit substitute pathways that tumor uses to evade the immune system and resistant to therapeutic agents.

RNA-SSNV: A Reliable Somatic Single Nucleotide Variant Identification Framework for Bulk RNA-Seq Data

The usage of expressed somatic mutations may have a unique advantage in identifying active cancer driver mutations. However, accurately calling mutations from RNA-seq data is difficult due to confounding factors such as RNA-editing, reverse transcription, and gap alignment. In the present study, we proposed a framework (named RNA-SSNV, https://github.com/pmglab/RNA-SSNV) to call somatic single nucleotide variants (SSNV) from tumor bulk RNA-seq data. Based on a comprehensive multi-filtering strategy and a machine-learning classification model trained with comprehensively curated features, RNA-SSNV achieved the best precision–recall rate (0.880–0.884) in a testing dataset and robustly retained 0.94 AUC for the precision–recall curve in three validation adult-based TCGA (The Cancer Genome Atlas) datasets. We further showed that the somatic mutations called by RNA-SSNV tended to have a higher functional impact and therapeutic power in known driver genes. Furthermore, VAF (variant allele fraction) analysis revealed that subclonal harboring expressed mutations had evolutional selection advantage and RNA had higher detection power to rescue DNA-omitted mutations. In sum, RNA-SSNV will be a useful approach to accurately call expressed somatic mutations for a more insightful analysis of cancer drive genes and carcinogenic mechanisms.

Wnt Signaling in the Breast: From Development to Disease

The Wnt cascade is a primordial developmental signaling pathway that plays a myriad of essential functions throughout development and adult homeostasis in virtually all animal species. Aberrant Wnt activity is implicated in embryonic and tissue morphogenesis defects, and several diseases, most notably cancer. The role of Wnt signaling in mammary gland development and breast cancer initiation, maintenance, and progression is far from being completely understood and is rather shrouded in controversy. In this review, we dissect the fundamental role of Wnt signaling in mammary gland development and adult homeostasis and explore how defects in its tightly regulated and intricated molecular network are interlinked with cancer, with a focus on the breast.

In vivo imaging of mammary epithelial cell dynamics in response to lineage-biased Wnt/β-catenin activation

Real-time in vivo imaging provides an essential window into the spatiotemporal cellular events contributing to tissue development and pathology. By coupling longitudinal intravital imaging with genetic lineage tracing, here we capture the earliest cellular events arising in response to active Wnt/β-catenin signaling and the ensuing impact on the organization and differentiation of the mammary epithelium. This enables us to interrogate how Wnt/β-catenin regulates the dynamics of distinct subpopulations of mammary epithelial cells in vivo and in real time. We show that β-catenin stabilization, when targeted to either the mammary luminal or basal epithelial lineage, leads to cellular rearrangements that precipitate the formation of hyperplastic lesions that undergo squamous transdifferentiation. These results enhance our understanding of the earliest stages of hyperplastic lesion formation in vivo and reveal that, in mammary neoplastic development, β-catenin activation dictates a hair follicle/epidermal differentiation program independently of the targeted cell of origin.

Emerging Roles of COX7RP and Mitochondrial Oxidative Phosphorylation in Breast Cancer

Metabolic alterations are critical events in cancers, which often contribute to tumor pathophysiology. While aerobic glycolysis is a known characteristic of cancer-related metabolism, recent studies have shed light on mitochondria-related metabolic pathways in cancer biology, including oxidative phosphorylation (OXPHOS), amino acid and lipid metabolism, nucleic acid metabolism, and redox regulation. Breast cancer is the most common cancer in women; thus, elucidation of breast cancer-related metabolic alteration will help to develop cancer drugs for many patients. We here aim to define the contribution of mitochondrial metabolism to breast cancer biology. The relevance of OXPHOS in breast cancer has been recently defined by the discovery of COX7RP, which promotes mitochondrial respiratory supercomplex assembly and glutamine metabolism: the latter is also shown to promote nucleic acid and fatty acid biosynthesis as well as ROS defense regulation. In this context, the estrogen-related receptor (ERR) family nuclear receptors and collaborating coactivators peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1) are essential transcriptional regulators for both energy production and cancer-related metabolism. Summarizing recent findings of mitochondrial metabolism in breast cancer, this review will aim to provide a clue for the development of alternative clinical management by modulating the activities of responsible molecules involved in disease-specific metabolic alterations.

The Prognostic Value of the Developmental Gene FZD6 in Young Saudi Breast Cancer Patients: A Biomarkers Discovery and Cancer Inducers OncoScreen Approach

Wnt signalling receptors, Frizzleds (FZDs), play a pivotal role in many cellular events during embryonic development and cancer. Female breast cancer (BC) is currently the worldwide leading incident cancer type that cause 1 in 6 cancer-related death. FZD receptors expression in cancer was shown to be associated with tumour development and patient outcomes including recurrence and survival. FZD6 received little attention for its role in BC and hence we analysed its expression pattern in a Saudi BC cohort to assess its prognostic potential and unravel the impacted signalling pathway. Paraffin blocks from approximately 405 randomly selected BC patients aged between 25 and 70 years old were processed for tissue microarray using an automated tissue arrayer and then subjected to FZD6 immunohistochemistry staining using the Ventana platform. Besides, Ingenuity Pathway Analysis (IPA) knowledgebase was used to decipher the upstream and downstream regulators of FZD6 in BC. TargetScan and miRabel target-prediction databases were used to identify the potential microRNA to regulate FZD6 expression in BC. Results showed that 60% of the BC samples had a low expression pattern while 40% showed a higher expression level. FZD6 expression analysis showed a significant correlation with tumour invasion (p < 0.05), and borderline significance with tumour grade (p = 0.07). FZD6 expression showed a highly significant association with the BC patients’ survival outcomes. This was mainly due to the overall patients’ cohort where tumours with FZD6 elevated expression showed higher recurrence rates (DFS, p < 0.0001, log-rank) and shorter survival times (DSS, p < 0.02, log-rank). Interestingly, the FZD6 prognostic value was more potent in younger BC patients as compared to those with late onset of the disease. TargetScan microRNA target-prediction analysis and validated by miRabel showed that FZD6 is a potential target for a considerable number of microRNAs expressed in BC. The current study demonstrates a potential prognostic role of FZD6 expression in young BC female patients and provides a better understanding of the involved molecular silencing machinery of the Wnt/FZD6 signalling. Our results should provide a better understanding of FZD6 role in BC by adding more knowledge that should help in BC prevention and theranostics.

The interaction of canonical Wnt/β-catenin signaling with protein lysine acetylation

Canonical Wnt/β-catenin signaling is a complex cell-communication mechanism that has a central role in the progression of various cancers. The cellular factors that participate in the regulation of this signaling are still not fully elucidated. Lysine acetylation is a significant protein modification which facilitates reversible regulation of the target protein function dependent on the activity of lysine acetyltransferases (KATs) and the catalytic function of lysine deacetylases (KDACs). Protein lysine acetylation has been classified into histone acetylation and non-histone protein acetylation. Histone acetylation is a kind of epigenetic modification, and it can modulate the transcription of important biological molecules in Wnt/β-catenin signaling. Additionally, as a type of post-translational modification, non-histone acetylation directly alters the function of the core molecules in Wnt/β-catenin signaling. Conversely, this signaling can regulate the expression and function of target molecules based on histone or non-histone protein acetylation. To date, various inhibitors targeting KATs and KDACs have been discovered, and some of these inhibitors exert their anti-tumor activity via blocking Wnt/β-catenin signaling. Here, we discuss the available evidence in understanding the complicated interaction of protein lysine acetylation with Wnt/β-catenin signaling, and lysine acetylation as a new target for cancer therapy via controlling this signaling.

Lvsiyujins A–G, new sesquiterpenoids, from Curcuma phaeocaulis Valeton root tuber and their preliminary pharmacological property assessment based on ADME evaluation, molecular docking and in vitro experiments

Seven new sesquiterpenoids were isolated from the root tuber of C. phaeocaulis. A combination of calculations and experiments was used in structural analysis and biological activity exploration.

G3BP1 promotes human breast cancer cell proliferation through coordinating with GSK-3β and stabilizing β-catenin

Ras-GTPase activating SH3 domain-binding protein 1 (G3BP1) is a multifunctional binding protein involved in the development of a variety of human cancers. However, the role of G3BP1 in breast cancer progression remains largely unknown. In this study, we report that G3BP1 is upregulated and correlated with poor prognosis in breast cancer. Overexpression of G3BP1 promotes breast cancer cell proliferation by stimulating β-catenin signaling, which upregulates a number of proliferation-related genes. We further show that G3BP1 improves the stability of β-catenin by inhibiting its ubiquitin-proteasome degradation rather than affecting the transcription of β-catenin. Mechanistically, elevated G3BP1 interacts with and inactivates GSK-3β to suppress β-catenin phosphorylation and degradation. Disturbing the G3BP1-GSK-3β interaction accelerates the degradation of β-catenin, impairing the proliferative capacity of breast cancer cells. Our study demonstrates that the regulatory mechanism of the G3BP1/GSK-3β/β-catenin axis may be a potential therapeutic target for breast cancer.

The role of R-spondin proteins in cancer biology

R-spondin (RSPO) proteins constitute a family of four secreted glycoproteins (RSPO1-4) that have appeared as multipotent signaling ligands. The best-known molecular function of RSPOs lie within their capacity to agonize the Wnt/β-catenin signaling pathway. As RSPOs act upon cognate receptors LGR4/5/6 that are typically expressed by stem cells and progenitor cells, RSPO proteins importantly potentiate Wnt/β-catenin signaling especially within these proliferative stem cell compartments. Since multiple organs express LGR4/5/6 receptors and RSPO ligands within their stem cell niches, RSPOs can exert an influential role in stem cell regulation throughout the body. Inherently, over the last decade a multitude of reports implicated the deregulation of RSPOs in cancer development. First, RSPO2 and RSPO3 gene fusions with concomitant enhanced expression have been identified in colon cancer patients, and proposed as an alternative driver of Wnt/β-catenin hyperactivation that earmarks cancer in the colorectal tract. Moreover, the causal oncogenic capacity of RSPO3 overactivation has been demonstrated in the mouse intestine. As a paradigm organ in this field, most of current knowledge about RSPOs in cancer is derived from studies in the intestinal tract. However, RSPO gene fusions as well as enhanced RSPO expression have been reported in multiple additional cancer types, affecting different organs that involve divergent stem cell hierarchies. Importantly, the emerging oncogenic role of RSPO and its potential clinical utility as a therapeutic target have been recognized and investigated in preclinical and clinical settings. This review provides a survey of current knowledge on the role of RSPOs in cancer biology, addressing the different organs implicated, and of efforts made to explore intervention opportunities in cancer cases with RSPO overrepresentation, including the potential utilization of RSPO as novel therapeutic target itself.

FAM83A Promotes the Proliferative and Invasive Abilities of Cervical Cancer Cells via Epithelial-Mesenchymal Transition and the Wnt Signaling Pathway

The family with sequence similarity 83, member A (FAM83A) gene is associated with the occurrence and development of many malignant tumors. Our aim was to explore the role of FAM83A in cervical cancer. FAM83A was overexpressed or knocked down in cervical cancer cells, and the expressions of FAM83A, key proteins involved in the epithelial-mesenchymal transition (EMT), and Wnt signaling pathway-related proteins were detected by western blot analysis. Cell proliferative and invasive abilities were also examined using cell proliferation, colony formation, and Matrigel invasion assays. Cells were treated with the Wnt pathway inhibitor XAV-939 to determine whether Wnt signaling was necessary for the effect of FAM83A on cervical cancer cells. FAM83A was highly expressed in cervical cancer tissues and was associated with differentiation, TNM stage, lymph node metastasis, and poor prognosis in patients with cervical cancer. Knockdown of FAM83A inhibited the proliferation, colony formation, and invasion of cervical cancer cells. The opposite results were observed in FAM83A-overexpressing cells, and FAM83A overexpression also promoted EMT and Wnt signaling. XAV-939 reversed the activation of Wnt signaling and EMT induced by FAM83A. In conclusion, FAM83A expression was increased in cervical cancers and correlated with poor prognosis of patients. FAM83A overexpression can activate the Wnt signaling pathway, facilitate EMT, and promote the proliferative and invasive abilities of cervical cancer cells.

The interactions of Bcl9/Bcl9L with β-catenin and Pygopus promote breast cancer growth, invasion, and metastasis

Canonical Wnt/β-catenin signaling is an established regulator of cellular state and its critical contributions to tumor initiation, malignant tumor progression and metastasis formation have been demonstrated in various cancer types. Here, we investigated how the binding of β-catenin to the transcriptional coactivators B-cell CLL/lymphoma 9 (Bcl9) and Bcl9-Like (Bcl9L) affected mammary gland carcinogenesis in the MMTV-PyMT transgenic mouse model of metastatic breast cancer. Conditional knockout of both Bcl9 and Bcl9L resulted into tumor cell death. In contrast, disrupting the interaction of Bcl9/Bcl9L with β-catenin, either by deletion of their HD2 domains or by a point mutation in the N-terminal domain of β-catenin (D164A), diminished primary tumor growth and tumor cell proliferation and reduced tumor cell invasion and lung metastasis. In comparison, the disruption of HD1 domain-mediated binding of Bcl9/Bcl9L to Pygopus had only moderate effects. Interestingly, interfering with the β-catenin-Bcl9/Bcl9L-Pygo chain of adapters only partially impaired the transcriptional response of mammary tumor cells to Wnt3a and TGFβ treatments. Together, the results indicate that Bcl9/Bcl9L modulate but are not critically required for canonical Wnt signaling in its contribution to breast cancer growth and malignant progression, a notion consistent with the “just-right” hypothesis of Wnt-driven tumor progression.

Proteomics and its applications in breast cancer

Breast cancer is an individually unique, multi-faceted and chameleonic disease, an eternal challenge for the new era of high-integrated precision diagnostic and personalized oncomedicine. Besides traditional single-omics fields (such as genomics, epigenomics, transcriptomics and metabolomics) and multi-omics contributions (proteogenomics, proteotranscriptomics or reproductomics), several new "-omics" approaches and exciting proteomics subfields are contributing to basic and advanced understanding of these "multiple diseases termed breast cancer": phenomics/cellomics, connectomics and interactomics, secretomics, matrisomics, exosomics, angiomics, chaperomics and epichaperomics, phosphoproteomics, ubiquitinomics, metalloproteomics, terminomics, degradomics and metadegradomics, adhesomics, stressomics, microbiomics, immunomics, salivaomics, materiomics and other biomics. Throughout the extremely complex neoplastic process, a Breast Cancer Cell Continuum Concept (BCCCC) has been modeled in this review as a spatio-temporal and holistic approach, as long as the breast cancer represents a complex cascade comprising successively integrated populations of heterogeneous tumor and cancer-associated cells, that reflect the carcinoma's progression from a "driving mutation" and formation of the breast primary tumor, toward the distant secondary tumors in different tissues and organs, via circulating tumor cell populations. This BCCCC is widely sustained by a Breast Cancer Proteomic Continuum Concept (BCPCC), where each phenotype of neoplastic and tumor-associated cells is characterized by a changing and adaptive proteomic profile detected in solid and liquid minimal invasive biopsies by complex proteomics approaches. Such a profile is created, beginning with the proteomic landscape of different neoplastic cell populations and cancer-associated cells, followed by subsequent analysis of protein biomarkers involved in epithelial-mesenchymal transition and intravasation, circulating tumor cell proteomics, and, finally, by protein biomarkers that highlight the extravasation and distant metastatic invasion. Proteomics technologies are producing important data in breast cancer diagnostic, prognostic, and predictive biomarkers discovery and validation, are detecting genetic aberrations at the proteome level, describing functional and regulatory pathways and emphasizing specific protein and peptide profiles in human tissues, biological fluids, cell lines and animal models. Also, proteomics can identify different breast cancer subtypes and specific protein and proteoform expression, can assess the efficacy of cancer therapies at cellular and tissular level and can even identify new therapeutic target proteins in clinical studies.

LINC01189-miR-586-ZEB1 feedback loop regulates breast cancer progression through Wnt/β-catenin signaling pathway

Non-coding RNAs play essential roles in breast cancer progression by regulating proliferation, differentiation, invasion, and metastasis. However, our understanding of most microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) in breast cancer is still limited. miR-586 has been identified as an important factor in the progression of some types of cancer, but its exact function and relative regulation mechanisms in breast cancer development need to be further investigated. In this study, we showed miR-586 functioned as an oncogene by promoting breast cancer proliferation and metastasis both in vitro and in vivo. Meanwhile, miR-586 induced Wnt/β-catenin activation by directly targeting Wnt/β-catenin signaling antagonists SFRP1 and DKK2/3. Moreover, we demonstrated that LINC01189 functioned as a tumor suppressor and inhibited breast cancer progression through inhibiting an epithelial-mesenchymal transition (EMT)-like phenotype by sponging miR-586. In addition, β-catenin/TCF4 transactivated ZEB1, resulting in a transcriptional repression of LINC01189 expression. In conclusion, our data uncovered the LINC01189-miR-586-ZEB1 feedback loop and provided a novel mechanism participating in the regulation of Wnt/β-catenin signaling in breast cancer progression.

CIRP promotes the progression of non-small cell lung cancer through activation of Wnt/β-catenin signaling via CTNNB1

BACKGROUND

Cold-inducible RNA binding protein (CIRP) is a newly discovered proto-oncogene. In this study, we investigated the role of CIRP in the progression of non-small cell lung cancer (NSCLC) using patient tissue samples, cultured cell lines and animal lung cancer models.

METHODS

Tissue arrays, IHC and HE staining, immunoblotting, and qRT-PCR were used to detect the indicated gene expression; plasmid and siRNA transfections as well as viral infection were used to manipulate gene expression; cell proliferation assay, cell cycle analysis, cell migration and invasion analysis, soft agar colony formation assay, tail intravenous injection and subcutaneous inoculation of animal models were performed to study the role of CIRP in NSCLC cells; Gene expression microarray was used to select the underlying pathways; and RNA immunoprecipitation assay, biotin pull-down assay, immunopurification assay, mRNA decay analyses and luciferase reporter assay were performed to elucidate the mechanisms. The log-rank (Mantel-Cox) test, independent sample T-test, nonparametric Mann-Whitney test, Spearman rank test and two-tailed independent sample T-test were used accordingly in our study.

RESULTS

Our data showed that CIRP was highly expressed in NSCLC tissue, and its level was negatively correlated with the prognosis of NSCLC patients. By manipulating CIRP expression in A549, H460, H1299, and H1650 cell lines, we demonstrated that CIRP overexpression promoted the transition of G1/G0 phase to S phase and the formation of an enhanced malignant phenotype of NSCLC, reflected by increased proliferation, enhanced invasion/metastasis and greater tumorigenic capabilities both in vitro and in vivo. Transcriptome sequencing further demonstrated that CIRP acted on the cell cycle, DNA replication and Wnt signaling pathway to exert its pro-oncogenic action. Mechanistically, CIRP directly bound to the 3'- and 5'-UTRs of CTNNB1 mRNA, leading to enhanced stability and translation of CTNNB1 mRNA and promoting IRES-mediated protein synthesis, respectively. Eventually, the increased CTNNB1 protein levels mediated excessive activation of the Wnt/β-catenin signaling pathway and its downstream targets C-myc, COX-2, CCND1, MMP7, VEGFA and CD44.

CONCLUSION

Our results support CIRP as a candidate oncogene in NSCLC and a potential target for NSCLC therapy.

The multidimensional role of the Wnt/β-catenin signaling pathway in human malignancies

Several signaling pathways have been identified as important for developmental processes. One of such important cascades is the Wnt/β-catenin signaling pathway, which can regulate various physiological processes such as embryonic development, tissue homeostasis, and tissue regeneration; while its dysregulation is implicated in several pathological conditions especially cancers. Interestingly, deregulation of the Wnt/β-catenin pathway has been reported to be closely associated with initiation, progression, metastasis, maintenance of cancer stem cells, and drug resistance in human malignancies. Moreover, several genetic and experimental models support the inhibition of the Wnt/β-catenin pathway to answer the key issues related to cancer development. The present review focuses on different regulators of Wnt pathway and how distinct mutations, deletion, and amplification in these regulators could possibly play an essential role in the development of several cancers such as colorectal, melanoma, breast, lung, and leukemia. Additionally, we also provide insights on diverse classes of inhibitors of the Wnt/β-catenin pathway, which are currently in preclinical and clinical trial against different cancers.

Myeloid cell leukemia 1 (MCL-1): Structural characteristics and application in cancer therapy

Apoptosis, a major hallmark of cancer cells, regulates cellular fate and homeostasis. BCL-2 (B-cell CLL/Lymphoma 2) protein family is popularly known to mediate the intrinsic mode of apoptosis, of which MCL-1 is a crucial member. Myeloid cell leukemia 1 (MCL-1) is an anti-apoptotic oncoprotein and one of the most investigated members of the BCL-2 family. It is commonly known to be genetically altered, aberrantly overexpressed, and primarily associated with drug resistance in various human cancers. Recent advancements in the development of selective MCL-1 inhibitors and evaluating their effectiveness in cancer treatment establish its popularity as a molecular target. The overall aim is the selective induction of apoptosis in cancer cells by using a single or combination of BCL-2 family inhibitors. Delineating the precise molecular mechanisms associated with MCL-1-mediated cancer progression will certainly improve the efficacy of clinical interventions aimed at MCL-1 and hence patient survival. This review is structured to highlight the structural characteristics of MCL-1, its specific interactions with NOXA, MCL-1-regulatory microRNAs, and at the same time focus on the emerging therapeutic strategies targeting our protein of interest (MCL-1), alone or in combination with other treatments.

Global Alternative Splicing Defects in Human Breast Cancer Cells

Simple Summary

Aberrant alternative splicing (AS) regulation plays a pivotal role in breast cancer development, progression, and resistance to therapeutical interventions. Indeed, cancer cells can adapt their own transcriptome by changing different AS programs, thus generating cancer-specific AS isoforms involved in every hallmark of cancer. Here, we investigated global AS errors occurring in human breast cancer cells by using RNA-mediated oligonucleotide annealing, selection, and ligation coupled with next-generation sequencing. Our results identified several dysregulated AS events potentially relevant for breast cancer-related biological processes and that provide a better comprehension of the molecular mechanisms that orchestrate the malignant transformation.

Abstract

Breast cancer is the most frequently occurred cancer type and the second cause of death in women worldwide. Alternative splicing (AS) is the process that generates more than one mRNA isoform from a single gene, and it plays a major role in expanding the human protein diversity. Aberrant AS contributes to breast cancer metastasis and resistance to chemotherapeutic interventions. Therefore, identifying cancer-specific isoforms is the prerequisite for therapeutic interventions intended to correct aberrantly expressed AS events. Here, we performed RNA-mediated oligonucleotide annealing, selection, and ligation coupled with next-generation sequencing (RASL-seq) in breast cancer cells, to identify global breast cancer-specific AS defects. By RT-PCR validation, we demonstrate the high accuracy of RASL-seq results. In addition, we analyzed identified AS events using the Cancer Genome Atlas (TCGA) database in a large number of non-pathological and breast tumor specimens and validated them in normal and breast cancer samples. Interestingly, aberrantly regulated AS cassette exons in cancer tissues do not encode for known functional domains but instead encode for amino acids constituting regions of intrinsically disordered protein portions characterized by high flexibility and prone to be subjected to post-translational modifications. Collectively, our results reveal novel AS errors occurring in human breast cancer, potentially affecting breast cancer-related biological processes.

Identification of a Two-MicroRNA Signature in Plasma as a Novel Biomarker for Very Early Diagnosis of Breast Cancer

Simple Summary

Breast cancer diagnosis at the initial stage of the disease considerably improves prognosis and survival rates. This retrospective study aimed to develop and validate a plasma microRNA signature as a non-invasive biomarker for early-stage breast cancer diagnosis. We confirmed in a testing cohort of 54 BC patients and 89 healthy volunteers the value of a signature based on miR-30b and miR-99a levels in plasma samples for stage I breast cancer detection. Furthermore, our results were blindly validated in a second cohort of 74 breast cancer and 74 healthy samples. The proposed microRNA signature presented high value as a fast, cost-effective, and non-invasive biomarker for early-stage breast cancer detection, which will lead to a better prognosis for breast cancer patients.

Abstract

The early diagnosis of breast cancer is essential to improve patients’ survival rate. In this context, microRNAs have been described as potential diagnostic biomarkers for breast cancer. Particularly, circulating microRNAs have a strong value as non-invasive biomarkers. Herein, we assessed the potential of a microRNA signature based on miR-30b-5p and miR-99a-5p levels in plasma as a diagnostic biomarker for breast cancer. This two-microRNA signature was constructed by Principal Component Analysis and its prognostic value was assessed in a discovery cohort and blindly validated in a second cohort from an independent institution. ROC curve analysis and biomarker performance parameter evaluation demonstrated that our proposed signature presents a high value as a non-invasive biomarker for very early detection of breast cancer. In addition, pathway enrichment analysis identified three of the well-known pathways involved in cancer as targets of the two microRNAs.

Transgenic mouse models of breast cancer

Transgenic breast cancer mouse models are critical tools for preclinical studies of human breast cancer. Genetic editing of the murine mammary gland allows for modeling of abnormal genetic events frequently found in human breast cancers. Genetically engineered mouse models (GEMMs) of breast cancer employ tissue-specific genetic manipulation for tumorigenic induction within the mammary tissue. Under the transcriptional control of mammary-specific promoters, transgenic mouse models can simulate spontaneous mammary tumorigenesis by expressing one or more putative oncogenes, such as MYC, HRAS, and PIK3CA. Alternatively, the Cre-Lox system allows for tissue-specific deletion of tumor suppressors, such as p53, Rb1, and Brca1, or specific knock-in of putative oncogenes. Thus, GEMMs can be designed to implement one or more genetic events to induce mammary tumorigenesis. Features of GEMMs, such as age of transgene expression, breeding quality, tumor latency, histopathological characteristics, and propensity for local and distant metastasis, are variable and strain-dependent. This review aims to summarize currently available transgenic breast cancer mouse models that undergo spontaneous mammary tumorigenesis upon genetic manipulation, their varying characteristics, and their individual genetic manipulations that model aberrant signaling events observed in human breast cancers.

Non-Polar Myxococcus fulvus KYC4048 Metabolites Exert Anti-Proliferative Effects via Inhibition of Wnt/β-Catenin Signaling in MCF-7 Breast Cancer Cells

The Wnt/β-catenin signaling pathway is involved in breast cancer and Myxococcus fulvus KYC4048 is a myxobacterial strain that can produce a variety of bioactive secondary metabolites. Although a previous study revealed that KYC4048 metabolites exhibit anti-proliferative effects on breast cancer, the biochemical mechanism involved in their effects remains unclear. In the present study, KYC4048 metabolites were separated into polar and non-polar (ethyl acetate and n-hexane) fractions via liquid-liquid extraction. The effects of these polar and non-polar KYC4048 metabolites on the viability of breast cancer cells were then determined by MTT assay. Expression levels of Wnt/β-catenin pathway proteins were determined by Western blot analysis. Cell cycle and apoptosis were measured via fluorescence-activated cell sorting (FACS). The results revealed that non-polar KYC4048 metabolites induced cell death of breast cancer cells and decreased expression levels of WNT2B, β-catenin, and Wnt target genes (c-Myc and cyclin D1). Moreover, the n-hexane fraction of non-polar KYC4048 metabolites was found most effective in inducing apoptosis, necrosis, and cell cycle arrest, leading us to conclude that it can induce apoptosis of breast cancer cells through the Wnt/β-catenin pathway. These findings provide evidence that the n-hexane fraction of non-polar KYC4048 metabolites can be developed as a potential therapeutic agent for breast cancer via inhibition of the Wnt/β-catenin pathway.

Ribosomal RNA Transcription Regulation in Breast Cancer

Ribosome biogenesis is a complex process that is responsible for the formation of ribosomes and ultimately global protein synthesis. The first step in this process is the synthesis of the ribosomal RNA in the nucleolus, transcribed by RNA Polymerase I. Historically, abnormal nucleolar structure is indicative of poor cancer prognoses. In recent years, it has been shown that ribosome biogenesis, and rDNA transcription in particular, is dysregulated in cancer cells. Coupled with advancements in screening technology that allowed for the discovery of novel drugs targeting RNA Polymerase I, this transcriptional machinery is an increasingly viable target for cancer therapies. In this review, we discuss ribosome biogenesis in breast cancer and the different cellular pathways involved. Moreover, we discuss current therapeutics that have been found to affect rDNA transcription and more novel drugs that target rDNA transcription machinery as a promising avenue for breast cancer treatment.

Prolactin synergizes with canonical Wnt signals to drive development of ER+ mammary tumors via activation of the Notch pathway

Prolactin (PRL) cooperates with other factors to orchestrate mammary development and lactation, and is epidemiologically linked to higher risk for breast cancer. However, how PRL collaborates with oncogenes to foster tumorigenesis and influence breast cancer phenotype is not well understood. To understand its interactions with canonical Wnt signals, which elevate mammary stem cell activity, we crossed heterozygous NRL-PRL mice with Apc^Min/+ mice and treated pubertal females with a single dose of mutagen. PRL in the context of Apc^Min/+ fueled a dramatic increase in tumor incidence in nulliparous mice, compared to Apc^Min/+ alone. Although carcinomas in both NRL-PRL/Apc^Min/+ and Apc^Min/+ females acquired a mutation in the remaining wildtype Apc allele and expressed abundant β-catenin, PRL-promoted tumors displayed higher levels of Notch-driven target genes and Notch-dependent cancer stem cell activity, compared to β-catenin-driven activity in Apc^Min/+ tumors. This PRL-induced shift to dominant Notch signals was evident in preneoplastic epithelial hyperplasias at 120 days of age. In NRL-PRL/Apc^Min/+ females, rapidly proliferating hyperplasias, characterized by β-catenin at cell junctions and high NOTCH1 expression, contrasted with slower growing lesions with nuclear β-catenin in Apc^Min/+ females. These studies demonstrate that PRL can powerfully modulate the incidence and phenotype of mammary tumors, shedding light on mechanisms whereby PRL elevates risk of breast cancer.

A Procarcinogenic Colon Microbe Promotes Breast Tumorigenesis and Metastatic Progression and Concomitantly Activates Notch and β-Catenin Axes

The existence of distinct breast microbiota has been recently established, but their biological impact in breast cancer remains elusive. Focusing on the shift in microbial community composition in diseased breast compared with normal breast, we identified the presence of Bacteroides fragilis in cancerous breast. Mammary gland as well as gut colonization with enterotoxigenic Bacteroides fragilis (ETBF), which secretes B. fragilis toxin (BFT), rapidly induces epithelial hyperplasia in the mammary gland. Breast cancer cells exposed to BFT exhibit "BFT memory" from the initial exposure. Intriguingly, gut or breast duct colonization with ETBF strongly induces growth and metastatic progression of tumor cells implanted in mammary ducts, in contrast to nontoxigenic Bacteroides fragilis. This work sheds light on the oncogenic impact of a procarcinogenic colon bacterium ETBF on breast cancer progression, implicates the β-catenin and Notch1 axis as its functional mediators, and proposes the concept of "BFT memory" that can have far-reaching biological implications after initial exposure to ETBF. SIGNIFICANCE: B. fragilis is an inhabitant of breast tissue, and gut or mammary duct colonization with ETBF triggers epithelial hyperplasia and augments breast cancer growth and metastasis. Short-term exposure to BFT elicits a "BFT memory" with long-term implications, functionally mediated by the β-catenin and Notch1 pathways.This article is highlighted in the In This Issue feature, p. 995.