Dvl2-dependent activation of Daam1 and RhoA regulates Wnt5a-induced breast cancer cell migration

RNA Sequencing Reveals the Inhibitory Effect of High Levels of Arachidonic Acid and Linoleic Acid on C2C12 Differentiation and Myogenic Biomarkers

Over the past three decades, studies have shown that consuming polyunsaturated fatty acids (PUFAs) can enhance animal and human health and welfare through biological, biochemical, pathological, and pharmacological impacts. Furthermore, omega-6 plays key roles in the cardiopulmonary system, including promoting airway relaxation and inhibiting atherosclerosis and hypertension. However, findings from investigations of the effects of omega-6 fatty acids on molecular and cellular activity and discussions on their influence on biomarkers are still unclear. Therefore, the present study aimed to evaluate omega-6 fatty acids, the arachidonic acid (AA), and linoleic acid (LA) effects on C2C12 proliferation, myogenesis morphology, and relative myogenic biomarker expression through the Wnt pathway. C2C12 cells were cultured with and without 25, 50, 100, and 150 µM of LA and AA and then subjected to CCK8, Giemsa staining, RT qPCR, Western blotting, and RNA Sequencing. The CCK8 Assay results showed that 25, 50, 100, and 150 µM LA significantly decreased the viability after 72 h for 25, 50, 100, and 150 µM concentrations. Also, AA supplementation decreased cell viability after 24 h for 150 µM, 48 h for 150 µM, and 72 h for 50, 100, and 150 µM concentrations. Moreover, the LA and AA inhibitory effects noticed through Gimesa staining were morphological changes during myoblast differentiation. Both LA and AA showed inhibiting IGF1, Cola1, Col6a2, Col6a1, Itga10, Itga11, SFRP2, DAAM2, and NKD2 effects; however, the depressing effect was higher for AA compared to LA. The previous results were confirmed through Western blotting, which showed that 50 µM LA and AA significantly reduced DAAM2 and SFRP2 protein levels compared to the control. Regarding RNA sequencing results, LA and AA increased the number of differentially expressed (DE) Mt-rRNA and snoRNA; however, the numbers of lncRNA detected decreased compared to the control. Our findings demonstrate that high and moderate LA and AA concentrations reduce primary myoblast proliferation and differentiation. Also, they highlight novel biomarkers and regulatory factors to improve our understanding of how the nutrition of fatty acids can control and modulate the myogenesis and differentiation process through different biomarker families.

The crucial role of fascin-1 in the pathogenesis, metastasis, and chemotherapeutic resistance of breast cancer

Breast cancer (BC) is the most common type of cancer in women to be diagnosed, and it is also the second leading cause of cancer death in women globally. It is the disease that causes the most life years adjusted for disability lost among women, making it a serious worldwide health issue. Understanding and interpreting carcinogenesis and metastatic pathways is critical for curing malignancy. Fascin-1 was recognized as an actin-bundling protein with parallel, rigid bundles as a result of the cross-linking of F-actin microfilaments. Increasing levels of fascin-1 have been associated with bad prognostic profiles, aggressiveness of clinical courses, and poor survival outcomes in a variety of human malignancies. Cancer cells that overexpress fascin-1 have higher capabilities for proliferation, invasion, migration, and metastasis. Fascin-1 is being considered as a potential target for therapy as well as a potential biomarker for diagnostics in a variety of cancer types. This review aims to provide an overview of the FSCN1 gene and its protein structure, elucidate its physiological and pathological roles, and throw light on its involvement in the initiation, development, and chemotherapeutic resistance of BC.

The novel role of etoposide in inhibiting the migration and proliferation of small cell lung cancer and breast cancer via targeting Daam1

OBJECTIVES

Daam1 (Dishevelled-associated activator of morphogenesis 1) is a Wnt/PCP signaling protein that engages in cytoskeleton reorganization and is abnormally activated in certain tumors. Daam1 is closely related to cancer metastasis, which is expected to become a target for cancer treatment. However, the natural small molecules targeting Daam1 have not been identified.

MATERIALS AND METHODS

We screened several natural small molecules that may bind to Daam1 by Sybyl molecular simulation docking technique. As a first-line drug for the treatment of small cell lung cancer, etoposide was chosen for further investigation. Next, we used Micro Scale Thermophoresis (MST) to verify the interaction of etoposide and Daam1. Small cell lung cancer H446 cells and breast cancer MCF-7 cells were treated with etoposide and subjected to Western blotting to measure the Daam1 expression. The effect of etoposide on cell proliferation was determined by CCK-8 assay in vitro and by a tumor-bearing mouse model in vivo. Wound healing assay and Boyden chamber assay were used to evaluate the role of etoposide in the migration and invasion ability of tumor cells. The effect of etoposide on the microfilament assembly was visualized by immunofluorescence staining with phalloidine. Finally, the possible mechanism of down-regulation of Daam1 expression after etoposide-induced small cell lung cancer cells was detected by a half-life experiment and immunofluorescence staining with lysosomal marker LAMP1.

RESULTS

Sybyl molecular modeling docking technique was performed to screen a natural chemical library for molecules that bound to the FH2 domain of Daam1 and found etoposide was virtually interacted with Daam1. MST validated etoposide directly bound to the FH2 domain of Daam1. Etoposide significantly down-regulated the expression of Daam1 in small cell lung cancer H446 cells and breast cancer MCF-7 cells. Moreover, 270 μmol/L etoposide largely inhibited the proliferation, migration, and invasion of H446 cells and MCF-7 cells. Immunofluorescence staining experiments revealed that etoposide induced the disassembly of microfilaments in H446 cells and MCF-7 cells, which were rescued by Daam1 overexpression. In nude mice transplanted with H446 cells, 5, 10, 20 mg/kg etoposide (drug/weight) injected via tail vein largely retarded the proliferation of subcutaneous tumors. Etoposide induced Daam1 to shorten its half-life and enter the lysosome degradation pathway, and eventually leading to the downregulation of Daam1 expression.

CONCLUSIONS

Etoposide is a novel natural small molecule targeting Daam1. Etoposide inhibits the proliferation, migration and invasion of small cell lung cancer cells and breast cancer cells, and also suppresses tumor proliferation of small cell lung cancer in vivo.

The Novel Small Molecule BTB Inhibits Pro-Fibrotic Fibroblast Behavior though Inhibition of RhoA Activity

Idiopathic pulmonary fibrosis (IPF) is a progressive, chronic, interstitial lung disease with a poor prognosis. Although specific anti-fibrotic medications are now available, the median survival time following diagnosis remains very low, and new therapies are urgently needed. To uncover novel therapeutic targets, we examined how biochemical properties of the fibrotic lung are different from the healthy lung. Previous work identified lactate as a metabolite that is upregulated in IPF lung tissue. Importantly, inhibition of the enzyme responsible for lactate production prevents fibrosis in vivo. Further studies revealed that fibrotic lesions of the lung experience a significant decline in tissue pH, likely due to the overproduction of lactate. It is not entirely clear how cells in the lung respond to changes in extracellular pH, but a family of proton sensing G-protein coupled receptors has been shown to be activated by reductions in extracellular pH. This work examines the expression profiles of proton sensing GPCRs in non-fibrotic and IPF-derived primary human lung fibroblasts. We identify TDAG8 as a proton sensing GPCR that is upregulated in IPF fibroblasts and that knockdown of TDAG8 dampens myofibroblast differentiation. To our surprise, BTB, a proposed positive allosteric modulator of TDAG8, inhibits myofibroblast differentiation. Our data suggest that BTB does not require TDAG8 to inhibit myofibroblast differentiation, but rather inhibits myofibroblast differentiation through suppression of RhoA mediated signaling. Our work highlights the therapeutic potential of BTB as an anti-fibrotic treatment and expands upon the importance of RhoA-mediated signaling pathways in the context of myofibroblast differentiation. Furthermore, this works also suggests that TDAG8 inhibition may have therapeutic relevance in the treatment of IPF.

Interpretation of the role of germline and somatic non-coding mutations in cancer: expression and chromatin conformation informed analysis

BACKGROUND

There has been extensive scrutiny of cancer driving mutations within the exome (especially amino acid altering mutations) as these are more likely to have a clear impact on protein functions, and thus on cell biology. However, this has come at the neglect of systematic identification of regulatory (non-coding) variants, which have recently been identified as putative somatic drivers and key germline risk factors for cancer development. Comprehensive understanding of non-coding mutations requires understanding their role in the disruption of regulatory elements, which then disrupt key biological functions such as gene expression.

MAIN BODY

We describe how advancements in sequencing technologies have led to the identification of a large number of non-coding mutations with uncharacterized biological significance. We summarize the strategies that have been developed to interpret and prioritize the biological mechanisms impacted by non-coding mutations, focusing on recent annotation of cancer non-coding variants utilizing chromatin states, eQTLs, and chromatin conformation data.

CONCLUSION

We believe that a better understanding of how to apply different regulatory data types into the study of non-coding mutations will enhance the discovery of novel mechanisms driving cancer.

Hippo signaling pathway: A comprehensive gene expression profile analysis in breast cancer

Breast cancer (BC) is the most frequently diagnosed malignancy in women and a major public health concern. The Hippo pathway is an evolutionarily conserved signaling pathway that serves as a key regulator for a wide variety of biological processes. Hippo signaling has been shown to have both oncogenic and tumor-suppressive functions in various cancers. Core components of the Hippo pathway consist of various kinases and downstream effectors such as YAP/TAZ. In the current report, differential expression of Hippo pathway elements as well as the correlation of Hippo pathway mRNAs with various clinicopathologic characteristics, including molecular subtypes, receptor status, and methylation status, has been investigated in BC using METABRIC and TCGA datasets. In this review, we note deregulation of several Hippo signaling elements in BC patients. Moreover, we see examples of negative correlations between methylation of Hippo genes and mRNA expression. The expression of Hippo genes significantly varies between different receptor subgroups. Because of the clear associations between mRNA expression and methylation status, DNA methylation may be one of the mechanisms that regulate the Hippo pathway in BC cells. Differential expression of Hippo genes among various BC molecular subtypes suggests that Hippo signaling may function differently in different subtypes of BC. Our data also highlights an interesting link between Hippo components' transcription and ER negativity in BC. In conclusion, substantial deregulation of Hippo signaling components suggests an important role of these genes in breast cancer.

The role of network-forming collagens in cancer progression

Collagens are the main components of extracellular matrix in the tumor microenvironment. Both fibrillar and nonfibrillar collagens are involved in tumor progression. The nonfibrillar network-forming collagens such as type IV and type VIII collagens are frequently overexpressed in various types of human cancers, which promotes tumor cell proliferation, adhesion, invasion, metastasis and angiogenesis. Studies on the roles of these collagens have shed light on the mechanisms underpinning the effects of this protein family. Future research has to explicit the role of network-forming collagens with respect to cancer progression and treatment. Herein, we review the regulation of network-forming collagens expression in cancer; the roles of network-forming collagens in tumor invasion, metastasis and angiogenesis; and the clinical significance of network-forming collagens expression in cancer patients. This article is protected by copyright. All rights reserved.

Dishevelled-Associated Activator of Morphogenesis 2 (DAAM2) Predicts the Immuno-Hot Phenotype in Pancreatic Adenocarcinoma

Background: DAAM2 participates in the oncogenesis and progression of human cancers. Although the role of DAAM2 in cancers has been preliminarily investigated, its correlations with antitumor immunity are unclear.

Methods: A pancancer analysis was conducted to explore the immunological role of DAAM2 based on RNA sequencing (RNA-seq) data downloaded from The Cancer Genome Atlas (TCGA). Next, correlations between DAAM2 and immunological characteristics in the tumor microenvironment (TME) of pancreatic adenocarcinoma (PAAD) were evaluated. In addition, the role of DAAM2 in predicting the clinical characteristics and the response to various therapies in PAAD were also assessed. In addition, the correlations between DAAM2 and the emerging immunobiomarker N6-methyladenosine (m6A) genes were also evaluated.

Results: Pancancer analysis revealed that DAAM2 exhibited positive correlations with a majority of immunomodulators, tumor-infiltrating immune cells (TIICs) and inhibitory immune checkpoints in several cancer types, including PAAD. In addition, DAAM2 was associated with an inflamed phenotype in the tumor microenvironment (TME). DAAM2 also predicted significantly higher responses to chemotherapy, anti-EGFR therapy and immunotherapy but lower responses to anti-ERBB2 and antiangiogenic therapy. In addition, DAAM2 was correlated with immune-related microbiota.

Conclusion: In PAAD, DAAM2 is associated with an immuno-hot phenotype and can help predict the outcome of various therapeutic options. Overall, DAAM2 is a promising indicator for assessing high immunogenicity in PAAD.

Nicotine treatment regulates PD-L1 and PD-L2 expression via inhibition of Akt pathway in HER2-type breast cancer cells

The immune checkpoint molecules such as PD-L1 and PD-L2 have a substantial contribution to cancer immunotherapy including breast cancer. Microarray expression profiling identified several molecular subtypes, namely luminal-type (with a good-prognosis), HER2-type (with an intermediate-prognosis), and triple-negative breast cancer (TNBC)-type (with a poor-prognosis). We found that PD-L1 and PD-L2 mRNA expressions were highly expressed in TNBC-type cell lines (HCC1937, MDA-MB-231), moderately expressed in HER2-type cell line (SK-BR-3), and poorly expressed in luminal-type cell lines (MDA-MB-361, MCF7). The PD-L1 and PD-L2 expression in SK-BR-3 cells, but not those in HCC1937 and MDA-MB-231 cells, decreased by nicotine stimulation in a dose-dependent manner. In addition, nicotine treatment decreased the phosphorylation of Akt in SK-BR-3 cells, but not in other cell lines. These results show that nicotine regulates the expression of immune checkpoint molecules, PD-L1 and PD-L2, via inhibition of Akt phosphorylation. This findings may provide the new therapeutic strategies for the treatment of breast cancer.

Triple-Negative Breast Cancer: A Brief Review About Epidemiology, Risk Factors, Signaling Pathways, Treatment and Role of Artificial Intelligence

Triple-negative breast cancer (TNBC) is a kind of breast cancer that lacks estrogen, progesterone, and human epidermal growth factor receptor 2. This cancer is responsible for more than 15–20% of all breast cancers and is of particular research interest as it is therapeutically challenging mainly because of its low response to therapeutics and highly invasive nature. The non-availability of specific treatment options for TNBC is usually managed by conventional therapy, which often leads to relapse. The focus of this review is to provide up-to-date information related to TNBC epidemiology, risk factors, metastasis, different signaling pathways, and the pathways that can be blocked, immune suppressive cells of the TNBC microenvironment, current and investigation therapies, prognosis, and the role of artificial intelligence in TNBC diagnosis. The data presented in this paper may be helpful for researchers working in the field to obtain general and particular information to advance the understanding of TNBC and provide suitable disease management in the future.

Phosphoproteomics identifies potential downstream targets of the integrin α2β1 inhibitor BTT-3033 in prostate stromal cells

Background

Integrin α2β1 inhibitor BTT-3033 (1-(4-fluorophenyl)-N-methyl-N-[4[[(phenylamino)carbonyl]amino]phenyl]-1H-pyrazole-4-sulfonamide) was recently reported to inhibit neurogenic and thromboxane A2-induced human prostate smooth muscle contraction, and thus represents a target with a different inhibition spectrum than that of α1-blockers in benign prostate hyperplasia (BPH) treatments. Clarifying the underlying mechanisms of the inhibition effects will provide insights into the role of integrin α2β1 in prostate contraction and enable new intracellular targets for smooth muscle contraction to be explored.

Methods

ProteomeHD was used to predict and enrich the top co-regulated proteins of integrin α2 (ITGA2). A phosphoproteomic analysis was conducted on human prostate stromal cells (WPMY-1) treated with 1 or 10 µM of BTT-3033 or solvent for controls. A clustering analysis was conducted to identify the intracellular targets that were inhibited in a dose-dependent manner. Gene ontology (GO) and annotation enrichments were conducted to examine any functional alterations and identify possible downstream targets. A Kinase-substrate enrichment analysis (KSEA) was conducted to identify kinases-substrate relationships.

Results

Enrichments of the actin cytoskeleton and guanosine triphosphatases (GTPases) signaling were predicted from the co-regulated proteins with ITGA2. LIM domain kinases, including LIM domain and actin-binding 1 (LIMA1), zyxin (ZYX), and thyroid receptor-interacting protein 6 (TRIP6), which are functionally associated with focal adhesions and the cytoskeleton, were present in the clusters with dose-dependent phosphorylation inhibition pattern. 15 substrates were dose-dependently inhibited according to the KSEA, including polo-like kinase 1 (PLK1), and GTPases signaling proteins, such as disheveled segment polarity protein 2 (DVL2).

Conclusions

In this study, we proposed that the mechanisms underlying the contractile and proliferative effects of integrin α2β1 are the LIM domain kinases, including the ZYX family, and substrates, including PLK1 and DVL2.

Dishevelled-1 DIX and PDZ domain lysine residues regulate oncogenic Wnt signaling

DVL proteins are central mediators of the Wnt pathway and relay complex input signals into different branches of the Wnt signaling network. However, molecular mechanism(s) that regulate DVL-mediated relay of Wnt signals still remains unclear. Here, for the first time, we elucidate the functional significance of three DVL-1 lysines (K/Lys) which are subject to post-translational acetylation. We demonstrate that K34 Lys residue in the DIX domain regulates subcellular localization of β-catenin, thereby influencing downstream Wnt target gene expression. Additionally, we show that K69 (DIX domain) and K285 (PDZ domain) regulate binding of DVL-1 to Wnt target gene promoters and modulate expression of Wnt target genes including CMYC, OCT4, NANOG, and CCND1, in cell line models and xenograft tumors. Finally, we report that conserved DVL-1 lysines modulate various oncogenic functions such as cell migration, proliferation, cell-cycle progression, 3D-spheroid formation and in-vivo tumor growth in breast cancer models. Collectively, these findings highlight the importance of DVL-1 domain-specific lysines which were recently shown to be acetylated and characterize their influence on Wnt signaling. These site-specific modifications may be subject to regulation by therapeutics already in clinical use (lysine deacetylase inhibitors such as Panobinostat and Vorinostat) or may possibly have prognostic utility in translational efforts that seek to modulate dysfunctional Wnt signaling.

Formins in Human Disease

Almost 25 years have passed since a mutation of a formin gene, DIAPH1, was identified as being responsible for a human inherited disorder: a form of sensorineural hearing loss. Since then, our knowledge of the links between formins and disease has deepened considerably. Mutations of DIAPH1 and six other formin genes (DAAM2, DIAPH2, DIAPH3, FMN2, INF2 and FHOD3) have been identified as the genetic cause of a variety of inherited human disorders, including intellectual disability, renal disease, peripheral neuropathy, thrombocytopenia, primary ovarian insufficiency, hearing loss and cardiomyopathy. In addition, alterations in formin genes have been associated with a variety of pathological conditions, including developmental defects affecting the heart, nervous system and kidney, aging-related diseases, and cancer. This review summarizes the most recent discoveries about the involvement of formin alterations in monogenic disorders and other human pathological conditions, especially cancer, with which they have been associated. In vitro results and experiments in modified animal models are discussed. Finally, we outline the directions for future research in this field.

YWHAZ interacts with DAAM1 to promote cell migration in breast cancer

Dishevelled-associated activator of morphogenesis 1 (DAAM1) is a critical driver in facilitating metastasis in breast cancer (BrCa). However, molecular mechanisms for the regulation of DAAM1 activation are only partially elucidated. In this research, the expression levels of YWHAZ and DAAM1 were examined by immunohistochemistry (IHC) staining in BrCa tissues. The functional roles of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ)–DAAM1 axis and their regulator microRNA-613 (miR-613) in BrCa cells and associated molecular mechanisms were demonstrated in vitro. As results, the expression levels of DAAM1 and YWHAZ were significantly upregulated in BrCa tissues compared with normal tissues and remarkably associated with poor prognosis. Besides, DAAM1 and YWHAZ were positively correlated with each other in BrCa tissues. YWHAZ interacted and colocalized with DAAM1 in BrCa cells, which was essential for DAAM1-mediated microfilament remodeling and RhoA activation. Moreover, miR-613 directly targeted both YWHAZ and DAAM1, contributing to inhibiting BrCa cells migration via blocking the complex of YWHAZ–DAAM1. To sum up, these data reveal that YWHAZ regulates DAAM1 activation, and the YWHAZ–DAAM1 complex is directly targeted by the shared post-transcriptional regulator miR-613.

Preliminary Investigation on the Involvement of Cytoskeleton-Related Proteins, DAAM1 and PREP, in Human Testicular Disorders

Herein, for the first time, the potential relationships between the cytoskeleton-associated proteins DAAM1 and PREP with different testicular disorders, such as classic seminoma (CS), Leydig cell tumor (LCT), and Sertoli cell-only syndrome (SOS), were evaluated. Six CS, two LCT, and two SOS tissue samples were obtained during inguinal exploration in patients with a suspect testis tumor based on clinical examination and ultrasonography. DAAM1 and PREP protein levels and immunofluorescent localization were analyzed. An increased DAAM1 protein level in CS and SOS as compared to non-pathological (NP) tissue was observed, while LCT showed no significant differences. Conversely, PREP protein level increased in LCT, while it decreased in CS and SOS compared to NP tissue. These results were strongly supported by the immunofluorescence staining, revealing an altered localization and signal intensity of DAAM1 and PREP in the analyzed samples, highlighting a perturbed cytoarchitecture. Interestingly, in LCT spermatogonia, a specific DAAM1 nuclear localization was found, probably due to an enhanced testosterone production, as confirmed by the increased protein levels of steroidogenic enzymes. Finally, although further studies are needed to verify the involvement of other formins and microtubule-associated proteins, this report raised the opportunity to indicate DAAM1 and PREP as new potential markers, supporting the cytoskeleton dynamics changes occurring during normal and/or pathological cell differentiation.

Wnt- and glutamate-receptors orchestrate stem cell dynamics and asymmetric cell division

The Wnt-pathway is part of a signalling network that regulates many aspects of cell biology. Recently, we discovered crosstalk between AMPA/Kainate-type ionotropic glutamate receptors (iGluRs) and the Wnt-pathway during the initial Wnt3a-interaction at the cytonemes of mouse embryonic stem cells (ESCs). Here, we demonstrate that this crosstalk persists throughout the Wnt3a-response in ESCs. Both AMPA and Kainate receptors regulate early Wnt3a-recruitment, dynamics on the cell membrane, and orientation of the spindle towards a Wnt3a-source at mitosis. AMPA receptors specifically are required for segregating cell fate components during Wnt3a-mediated asymmetric cell division (ACD). Using Wnt-pathway component knockout lines, we determine that Wnt co-receptor Lrp6 has particular functionality over Lrp5 in cytoneme formation, and in facilitating ACD. Both Lrp5 and 6, alongside pathway effector β-catenin act in concert to mediate the positioning of the dynamic interaction with, and spindle orientation to, a localised Wnt3a-source. Wnt-iGluR crosstalk may prove pervasive throughout embryonic and adult stem cell signalling.

Circulating Wnt Ligands Activate the Wnt Signaling Pathway in Mature Erythrocytes

[Figure: see text].

MicroRNAs as the critical regulators of Doxorubicin resistance in breast tumor cells

BACKGROUND

Chemotherapy is one of the most common treatment options for breast cancer (BC) patients. However, about half of the BC patients are chemotherapeutic resistant. Doxorubicin (DOX) is considered as one of the first line drugs in the treatment of BC patients whose function is negatively affected by multi drug resistance. Due to the severe side effects of DOX, it is very important to diagnose the DOX resistant BC patients. Therefore, assessment of molecular mechanisms involved in DOX resistance can improve the clinical outcomes in BC patients by introducing the novel therapeutic and diagnostic molecular markers. MicroRNAs (miRNAs) as members of the non-coding RNAs family have pivotal roles in various cellular processes including cell proliferation and apoptosis. Therefore, aberrant miRNAs functions and expressions can be associated with tumor progression, metastasis, and drug resistance. Moreover, due to miRNAs stability in body fluids, they can be considered as non-invasive diagnostic markers for the DOX response in BC patients.

MAIN BODY

In the present review, we have summarized all of the miRNAs that have been reported to be associated with DOX resistance in BC for the first time in the world.

CONCLUSIONS

Since, DOX has severe side effects; it is required to distinguish the non DOX-responders from responders to improve the clinical outcomes of BC patients. This review highlights the miRNAs as pivotal regulators of DOX resistance in breast tumor cells. Moreover, the present review paves the way of introducing a non-invasive panel of prediction markers for DOX response among BC patients.

A Non-canonical Wnt Signature Correlates With Lower Survival in Gastric Cancer

Genetic evidence suggests a role for the Wnt/β-catenin pathway in gastric cancer. However, Wnt5a, regarded as a prototypical non-canonical Wnt ligand, has also been extensively associated with this disease. Therefore, the roles of the Wnt signaling pathway in gastric cancer initiation and progression, and particularly the precise mechanisms by which the non-canonical Wnt pathway might promote the development and progression of gastric cancer, are not entirely well understood. This article analyzes publicly available gene and protein expression data and reveals the existence of a WNT5A/FZD2/FZD7/ROR2 signature, which correlates with tumor-infiltrating and mesenchymal cell marker expression. High expression of FZD7 and ROR2 correlates with a shared gene and protein expression profile, which in turn correlates with poor prognosis. In summary, the findings presented in this article provide an updated view of the relative contributions of the Wnt/β-catenin and non-canonical Wnt pathways in gastric cancer.

Formin homology domains of Daam1 bind to Fascin and collaboratively promote pseudopodia formation and cell migration in breast cancer

OBJECTIVES

Cancer cell migration to secondary organs remains an essential cause of death among breast cancer (BrCa) patients. Cell motility mainly relies on actin dynamics. Our previous reports verified that dishevelled-associated activator of morphogenesis 1 (Daam1) regulates invadopodia extension and BrCa cell motility. However, how Daam1 is involved in actin filament assembly and promotes pseudopodia formation in BrCa cells remains unclear.

MATERIALS AND METHODS

One hundred human BrCa samples were collected at Women's Hospital of Nanjing Medical University. Immunohistochemistry (IHC) was used to examine Daam1 and Fascin expression. Wound healing and Boyden chamber assays were used to explore cell migration and pseudopodia extension of BrCa cells. Co-IP/pull down and Western blotting were performed to study the physical interaction between Daam1 and Fascin. Immunofluorescence assays were performed to observe whether Daam1 and Fascin were colocalized and mediated actin filament assembly.

RESULTS

Fascin was upregulated in BrCa tissues compared with that in paracarcinoma tissues. The downregulation of Fascin caused a decline in pseudopodia formation and cell motility. Moreover, we found that Daam1 interacted with Fascin via formin homology (FH) domains, especially the FH2 domain. Immunofluorescence assays showed that Daam1 and Fascin partially colocalized to actin filaments, and the knockdown of Daam1 or Fascin failed to colocalize to short and curved actin filaments.

CONCLUSIONS

Daam1 specifically binds to Fascin via FH domains and cooperatively facilitates pseudopodia formation and cell migration by promoting actin filament assembly in BrCa.

The WNT/ROR Pathway in Cancer: From Signaling to Therapeutic Intervention

The WNT pathway is one of the major signaling cascades frequently deregulated in human cancer. While research had initially focused on signal transduction centered on β-catenin as a key effector activating a pro-tumorigenic transcriptional response, nowadays it is known that WNT ligands can also induce a multitude of β-catenin-independent cellular pathways. Traditionally, these comprise WNT/planar cell polarity (PCP) and WNT/Ca²⁺ signaling. In addition, signaling via the receptor tyrosine kinase-like orphan receptors (RORs) has gained increasing attention in cancer research due to their overexpression in a multitude of tumor entities. Active WNT/ROR signaling has been linked to processes driving tumor development and progression, such as cell proliferation, survival, invasion, or therapy resistance. In adult tissue, the RORs are largely absent, which has spiked the interest in them for targeted cancer therapy. Promising results in preclinical and initial clinical studies are beginning to unravel the great potential of such treatment approaches. In this review, we summarize seminal findings on the structure and expression of the RORs in cancer, their downstream signaling, and its output in regard to tumor cell function. Furthermore, we present the current clinical anti-ROR treatment strategies and discuss the state-of-the-art, as well as the challenges of the different approaches.

USP9X Deubiquitylates DVL2 to Regulate WNT Pathway Specification

The WNT signaling network is comprised of multiple receptors that relay various input signals via distinct transduction pathways to execute multiple complex and context-specific output processes. Integrity of the WNT signaling network relies on proper specification between canonical and noncanonical pathways, which presents a regulatory challenge given that several signal transducing elements are shared between pathways. Here, we report that USP9X, a deubiquitylase, and WWP1, an E3 ubiquitin ligase, regulate a ubiquitin rheostat on DVL2, a WNT signaling protein. Our findings indicate that USP9X-mediated deubiquitylation of DVL2 is required for canonical WNT activation, while increased DVL2 ubiquitylation is associated with localization to actin-rich projections and activation of the planar cell polarity (PCP) pathway. We propose that a WWP1-USP9X axis regulates a ubiquitin rheostat on DVL2 that specifies its participation in either canonical WNT or WNT-PCP pathways. These findings have important implications for therapeutic targeting of USP9X in human cancer.

DVL2 is a signal transducing protein that participates in canonical and noncanonical WNT signaling relays. Here, Nielsen et al. report that the deubiquitylase USP9X and the E3 ubiquitin ligase WWP1 operate on DVL2 to establish a ubiquitin rheostat that contributes to WNT pathway specification in human breast cancer cells.

CD146, from a melanoma cell adhesion molecule to a signaling receptor

CD146 was originally identified as a melanoma cell adhesion molecule (MCAM) and highly expressed in many tumors and endothelial cells. However, the evidence that CD146 acts as an adhesion molecule to mediate a homophilic adhesion through the direct interactions between CD146 and itself is still lacking. Recent evidence revealed that CD146 is not merely an adhesion molecule, but also a cellular surface receptor of miscellaneous ligands, including some growth factors and extracellular matrixes. Through the bidirectional interactions with its ligands, CD146 is actively involved in numerous physiological and pathological processes of cells. Overexpression of CD146 can be observed in most of malignancies and is implicated in nearly every step of the development and progression of cancers, especially vascular and lymphatic metastasis. Thus, immunotherapy against CD146 would provide a promising strategy to inhibit metastasis, which accounts for the majority of cancer-associated deaths. Therefore, to deepen the understanding of CD146, we review the reports describing the newly identified ligands of CD146 and discuss the implications of these findings in establishing novel strategies for cancer therapy.

Systematic summarization of the expression profiles and prognostic roles of the dishevelled gene family in hepatocellular carcinoma

Background

Dishevelled (DVL) family members are crucial to Wnt‐induced signaling transduction, and their expression is highly correlated with the progression of multiple malignant cancers. However, the expression profiles and exact prognostic values of DVLs in hepatocellular carcinoma (HCC) have not been explored until now.

Methods

The expression of DVL isoforms was assessed using the Oncomine, HCCDB and UALCAN databases. The prognostic roles of DVLs were further evaluated using the GEPIA database. The relationship between the expression of DVLs and immune infiltration of HCC was investigated using the Timer and ImmuCellAI tools. Furthermore, protein–protein interaction (PPI) networks were built and enrichment analyses were conducted.

Results

We found that the expression levels of DVL2 (OMIM accession number: 602151) and DVL3 (OMIM accession number: 601368) were upregulated in HCC tissues as revealed by the Oncomine and HCCDB databases. Additionally, the expression of DVLs tended to be associated with advanced clinical features in the UALCAN database. Prognostic analysis revealed that the expression levels of DVL1 (OMIM accession number: 601365) and DVL3 were remarkably associated with a poor prognosis in HCC patients. The results also revealed that the DVL expression level was correlated with the infiltration levels of multiple immune cells. By constructing the PPI network and enrichment analyses, the DVL1‐3 gene was identified to interact with 20 key genes and participate in several pathways.

Conclusion

In summary, DVL2 and DVL3 are highly expressed in HCC, and DVL1 and DVL3 are related to a poor prognosis, which might be used as candidate targets for targeted therapy and reliable prognostic biomarkers in HCC.

Implication of hsa_circ_0028007 in reinforcing migration, invasion, and chemo-tolerance of nasopharyngeal carcinoma cells

Background

Given the reliability of circRNAs in symbolizing cancer progression, this investigation was designed to expound the involvement of hsa_circ_0028007 in regulating chemosensitivity of nasopharyngeal carcinoma (NPC) cells.

Methods

Altogether, 241 pairs of NPC tissues and para‐cancerous normal tissues were collected to identify NPC‐symbolic circRNAs, which have been screened by circRNA microarray in advance. Expressions of the circRNAs were determined by means of real‐time polymerase chain reaction (PCR). Besides, human NPC cell lines (ie, CNE2 and HONE1) were transfected by si‐hsa_circ_0028007 and si‐NC. Scratch assay, transwell assay, and MTT assay were performed to assess migration, invasion, and paclitaxel/cisplatin‐resistance of NPC cell lines.

Results

Hsa_circ_0028007 expression was abnormally heightened within NPC tissues in comparison with matched non‐tumor tissues (P < .05). Over‐expressed hsa_circ_0028007 was strongly associated with advanced (III‐IV) tumor stage, aggressive infiltration, and metastatic lymph nodes of NPC patients (P < .05). Regarding in vitro experiments, hsa_circ_0028007 expression was elevated in CNE2 and HONE1 cell lines as compared with HENE cell line (P < .05). Silencing of hsa_circ_0028007 not merely sensitized CNE2 and HONE1 cells against paclitaxel and cisplatin (P < .05), but also significantly repressed migration and invasion of the cell lines (P < .05).

Conclusion

Hsa_circ_0028007 was involved in facilitating progression and chemo‐resistance of NPC, which might offer an alternative for NPC treatment.

CCR9 and CCL25: A review of their roles in tumor promotion

Chemokines constitute a superfamily of small chemotactic cytokines with functions that are based on interactions with their corresponding receptors. It has been found that, among other functions, chemokines regulate the migratory and invasive abilities of cancer cells. Multiple studies have confirmed that chemokine receptor 9 (CCR9) and its exclusive ligand, chemokine 25 (CCL25), are overexpressed in a variety of malignant tumors and are closely associated with tumor proliferation, apoptosis, invasion, migration and drug resistance. This review evaluates recent advances in understanding the role of CCR9/CCL25 in cancer development. First, we outline the general background of chemokines in cancer and the structure and function of CCR9 and CCL25. Next, we describe the basic function of CCR9/CCL25 in the cancer process. Then, we introduce the role of CCR9/CCL25 and related signaling pathways in various cancers. Finally, future research directions are proposed. In general, this paper is intended to serve as a comprehensive repository of information on this topic and is expected to contribute to the design of other research projects and future efforts to develop treatment strategies for ameliorating the effects of CCR9/CCL25 in cancer.

PHACTR1 is associated with disease progression in Chinese Moyamoya disease

Moyamoya disease (MMD) is a progressive stenosis at the terminal portion of internal carotid artery and frequently occurs in East Asian countries. The etiology of MMD is still largely unknown. We performed a case-control design with whole-exome sequencing analysis on 31 sporadic MMD patients and 10 normal controls with matched age and gender. Patients clinically diagnosed with MMD was determined by digital subtraction angiography (DSA). Twelve predisposing mutations on seven genes associated with the sporadic MMD patients of Chinese ancestry (CCER2, HLA-DRB1, NSD-1, PDGFRB, PHACTR1, POGLUT1, and RNF213) were identified, of which eight single nucleotide variants (SNVs) were deleterious with CADD PHRED scaled score > 15. Sanger sequencing of nine cases with disease progression and 22 stable MMD cases validated that SNV (c.13185159G>T, p.V265L) on PHACTR1 was highly associated with the disease progression of MMD. Finally, we knocked down the expression of PHACTR1 by transfection with siRNA and measured the cell survival of human coronary artery endothelial cell (HCAEC) cells. PHACTR1 silence reduced the cell survival of HCAEC cells under serum starvation cultural condition. Together, these data identify novel predisposing mutations associated with MMD and reveal a requirement for PHACTR1 in mediating cell survival of endothelial cells.

Biomimetic Presentation of Cryptic Ligands via Single-Chain Nanogels for Synergistic Regulation of Stem Cells

Dynamic controlling the nanoscale presentation of synergistic ligands to stem cells by biomimetic single-chain materials can provide critical insights to understand the molecular crosstalk underlying cells and their extracellular matrix. Here, a stimuli-responsive single-chain macromolecular nanoregulator with conformational dynamics is fabricated based on an advanced scale-up single polymeric chain nanogel (SCNG). Such a carefully designed SCNG is capable of mediating a triggered copresentation of the master and cryptic ligands in a single molecule to elicit the synergistic crosstalk between different intracellular signaling pathways, thereby considerably boosting the bioactivity of the presented ligands. This controllable nanoswitching-on of cell-adhesive ligands' presentation allows the regulation of cell adhesion and fate from molecular scale. The modular nature of this synthetic macromolecular nanoregulator makes it a versatile nanomaterial platform to assist basic and fundamental studies in a wide array of research topics.

Systematic characterization of non-coding RNAs in triple-negative breast cancer

Triple‐negative breast cancer (TNBC) is one of the most aggressive subtypes of breast cancer with negativity for oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor (HER2). Non‐coding RNAs (ncRNAs) make up most of the transcriptome and are widely present in eukaryotic cells. In recent years, emerging evidence suggests that ncRNAs, mainly microRNAs (miRNAs), long ncRNAs (lncRNAs) and circular RNAs (circRNAs), play prominent roles in the tumorigenesis and development of TNBC, but the functions of most ncRNAs have not been fully described. In this review, we systematically elucidate the general characteristics and biogenesis of miRNAs, lncRNAs and circRNAs, discuss the emerging functions of these ncRNAs in TNBC and present future perspectives in clinical practice.

Specialized cytonemes induce self-organization of stem cells

Spatial cellular organization is fundamental for embryogenesis. Remarkably, coculturing embryonic stem cells (ESCs) and trophoblast stem cells (TSCs) recapitulates this process, forming embryo-like structures. However, mechanisms driving ESC-TSC interaction remain elusive. We describe specialized ESC-generated cytonemes that react to TSC-secreted Wnts. Cytoneme formation and length are controlled by actin, intracellular calcium stores, and components of the Wnt pathway. ESC cytonemes select self-renewal-promoting Wnts via crosstalk between Wnt receptors, activation of ionotropic glutamate receptors (iGluRs), and localized calcium transients. This crosstalk orchestrates Wnt signaling, ESC polarization, ESC-TSC pairing, and consequently synthetic embryogenesis. Our results uncover ESC-TSC contact-mediated signaling, reminiscent of the glutamatergic neuronal synapse, inducing spatial self-organization and embryonic cell specification.

Triple-Negative Breast Cancer: A Review of Conventional and Advanced Therapeutic Strategies

Triple-negative breast cancer (TNBC) cells are deficient in estrogen, progesterone and ERBB2 receptor expression, presenting a particularly challenging therapeutic target due to their highly invasive nature and relatively low response to therapeutics. There is an absence of specific treatment strategies for this tumor subgroup, and hence TNBC is managed with conventional therapeutics, often leading to systemic relapse. In terms of histology and transcription profile these cancers have similarities to BRCA-1-linked breast cancers, and it is hypothesized that BRCA1 pathway is non-functional in this type of breast cancer. In this review article, we discuss the different receptors expressed by TNBC as well as the diversity of different signaling pathways targeted by TNBC therapeutics, for example, Notch, Hedgehog, Wnt/b-Catenin as well as TGF-beta signaling pathways. Additionally, many epidermal growth factor receptor (EGFR), poly (ADP-ribose) polymerase (PARP) and mammalian target of rapamycin (mTOR) inhibitors effectively inhibit the TNBCs, but they face challenges of either resistance to drugs or relapse. The resistance of TNBC to conventional therapeutic agents has helped in the advancement of advanced TNBC therapeutic approaches including hyperthermia, photodynamic therapy, as well as nanomedicine-based targeted therapeutics of drugs, miRNA, siRNA, and aptamers, which will also be discussed. Artificial intelligence is another tool that is presented to enhance the diagnosis of TNBC.

Mesenchymal stromal cell-derived exosomes improve pulmonary hypertension through inhibition of pulmonary vascular remodeling

Background

Pulmonary hypertension (PH) is a life-threatening disease characterized by pulmonary vascular remodeling, right ventricular hypertrophy and failure. So far no effective treatment exists for this disease; hence, novel approaches are urgently needed. The aim of the present research was to observe the treatment effect of mesenchymal stromal cell derived exosomes and reveal the mechanism.

Methods

Monocrotaline (MCT)-induced PH in rats and hypoxia-induced cell damage model were established, respectively. Exosomes derived from the supernatant of human umbilical cord mesenchymal stem cells (MSC-exo) were injected into MCT-PH model rat or added into the cells cultured medium. Immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot methods were used in vivo and vitro.

Results

The results showed that MSC-exo could significantly attenuate right ventricular (RV) hypertrophy and pulmonary vascular remodelling in MCT-PH rats. In the cell culture experiments, we found that MSC-exo could significantly inhibit hypoxia-induced pulmonary arterial endothelial cell (PAEC) apoptosis and pulmonary arterial smooth muscle cells (PASMC) proliferation. Furthermore, the pulmonary arterioles endothelial-to-mesenchymal transition (EndMT) was obviously suppressed. Moreover, the present study suggest that MSC-exo can significantly upregulate the expression of Wnt5a in MCT-PH rats and hypoxic pulmonary vascular cells. Furthermore, with Wnt5a gene silencing, the therapeutic effect of MSC-exo against hypoxia injury was restrained.

Conclusions

Synthetically, our data provide a strong evidence for the therapeutic of MSC-exo on PH, more importantly, we confirmed that the mechanism was associated with up-regulation of the expression of Wnt5a. These results offer a theoretical basis for clinical prevention and treatment of PH.

Genetic Polymorphisms in APC, DVL2, and AXIN1 Are Associated with Susceptibility, Advanced TNM Stage or Tumor Location in Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of death worldwide. The named "destruction complex" has a critical function in the Wnt/β-catenin pathway regulating the level of β-catenin in the cytoplasm and nucleus. Alterations in this complex lead to the cellular accumulation of β-catenin, which participates in the development and progression of CRC. This study aims to determine the contribution of polymorphisms in the genes of the β-catenin destruction complex to develop CRC, specifically adenomatous polyposis coli (APC) (rs11954856 G>T and rs459552 A>T), axis inhibition protein 1 (AXIN1) (rs9921222 C>T and rs1805105 C>T), AXIN2 (rs7224837 A>G), and dishevelled 2 (DVL2) (2074222 G>A and rs222836 C>T). Genomic DNA from 180 sporadic colorectal cancer patients and 150 healthy blood donors were analyzed. The identification of polymorphisms was made by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) methodology. Association was calculated by the odds ratio (OR) test. Increased susceptibility to CRC was associated with the polymorphic variants rs11954856 (APC), rs222836 (DVL2), and rs9921222 (AXIN1). Decreased susceptibility was associated with the polymorphisms rs459552 (APC) and 2074222 (DVL2). Association was also observed with advanced Tumor-Node-Metastasis (TNM) stages and tumor location. The haplotypes G-T in APC (rs11954856-rs459552) and A-C in DVL2 (rs2074222-rs222836) were associated with decreased risk of CRC, while the G-T haplotype in the DVL2 gene was associated with increased CRC risk. In conclusion, our results suggest that variants in the destruction complex genes may be involved in the promotion or prevention of colorectal cancer.

Wnt5a induces ROR1 to recruit cortactin to promote breast-cancer migration and metastasis

ROR1 is a conserved oncoembryonic surface protein expressed in breast cancer. Here we report that ROR1 associates with cortactin in primary breast-cancer cells or in MCF7 transfected to express ROR1. Wnt5a also induced ROR1-dependent tyrosine phosphorylation of cortactin (Y421), which recruited ARHGEF1 to activate RhoA and promote breast-cancer-cell migration; such effects could be inhibited by cirmtuzumab, a humanized mAb specific for ROR1. Furthermore, treatment of mice bearing breast-cancer xenograft with cirmtuzumab inhibited cortactin phosphorylation in vivo and impaired metastatic development. We established that the proline at 841 of ROR1 was required for it to recruit cortactin and ARHGEF1, activate RhoA, and enhance breast-cancer-cell migration in vitro or development of metastases in vivo. Collectively, these studies demonstrate that the interaction of ROR1 with cortactin plays an important role in breast-cancer-cell migration and metastasis.

Role of Wnt3a in the pathogenesis of cancer, current status and prospective

The Wnt signaling pathway plays a critical role in initiation, progression, invasion and metastasis of cancer. Wnt3a as a canonical Wnt ligand is strongly implicated in the etiology and pathology of a number of diseases including cancer. Depending on cancer type, Wnt3a enhances or suppresses metastasis, cell proliferation and apoptosis of cancer cells. This review summarizes the role of Wnt3a in the pathogenesis of different cancers including colorectal, prostate, hepatocellular, lung and leukemia, for promoting greater understanding and clinical management of these diseases.

WNT5A as a therapeutic target in breast cancer

Despite the clinical development of novel adjuvant and neoadjuvant chemotherapeutic drugs, metastatic breast cancer is one of the leading causes of cancer-related death among women. The present review focuses on the relevance, mechanisms, and therapeutic potential of targeting WNT5A as a future anti-metastatic treatment strategy for breast cancer patients by restoring WNT5A signaling as an innovative therapeutic option. WNT5A is an auto- and paracrine β-catenin-independent ligand that has been shown to induce tumor suppression as well as oncogenic signaling, depending upon cancer type. In breast cancer patients, WNT5A protein expression has been observed to be significantly reduced in between 45 and 75% of the cases and associated with early relapse and reduced disease-free survival. WNT5A triggers various downstream signaling pathways in breast cancer that primarily affect tumor cell migration and invasion. The accumulated in vitro results reveal that treatment of WNT5A-negative breast cancer cells with recombinant WNT5A caused different tumor-suppressive responses and in particular it impaired migration and invasion. The anti-migratory/invasive and anti-metastatic effects of reconstituting WNT5A signaling by the small WNT5A mimicking peptide Foxy5 form the basis for two successful clinical phase 1-studies aiming at determining safety and pharmacokinetics as well as defining dose-level for a subsequent phase 2-study. We conclude that re-installation of WNT5A signaling is an attractive and promising anti-metastatic therapeutic approach for future treatment of WNT5A-negative breast cancer patients.

Wnt5a induces ROR1 and ROR2 to activate RhoA in esophageal squamous cell carcinoma cells

Background: Wnt5a is a nontransforming Wnt family member and identified as an oncogenic role on cell motility of breast cancer and glioblastoma. However, Wnt5a signaling in esophageal squamous cell carcinoma (ESCC) progression remains poorly defined.

Materials and methods: Immunohistochemistry assays were used to measure the Wnt5a expression in ESCC sections. We evaluated the role of receptor tyrosine kinase-like orphan receptor (ROR)1/2 and RhoA on the invasion of ESCC cells by using cell invasion assay, immunoprecipitation, immunofluorescence, and Rho activation assay.

Results: Wnt5a was highly expressed in invasive ESCC tissues compared with that in noninvasive and nonmalignant tissues. In vitro assay showed that sfrp2 (Wnt5a antagonist) largely blocked the invasion but not the colony formation of KYSE410 and KYSE520 ESCC cells. Anti-ROR1 mAb and ROR2-shRNA markedly inhibited the disheveled-associated activator of morphogenesis 1 (DAAM1) activity, RhoA activity, microfilament formation and the invasion of ESCC cells. Fluorescent phalloidin staining experiment showed ROR1/ROR2, receptors of Wnt5a signaling, and regulated the reassembly of actin filaments in ESCC cells. Further experiments showed that ROR1 was strongly associated with ROR2 in KYSE410 cells. The activation of RhoA, not Rac1 or Rac2, was involved in ROR1/ROR2 signaling pathway. By using DAAM1 shRNA, we found that RhoA was downstream of DAAM1, which could be rescued by the overexpression of wild-type DAAM1. This could be further proved by a RhoA inhibitor CCG-1423 which could inhibit the invasion of ESCC cells but not DAAM1 activity.

Conclusions: Wnt5a promotes ESCC cell invasion via ROR1 and ROR2 receptors and DAAM1/RhoA signaling pathway.

A DAAM1 3'-UTR SNP mutation regulates breast cancer metastasis through affecting miR-208a-5p-DAAM1-RhoA axis

Background

Dishevelled-associated activator of morphogenesis 1 (DAAM1) is a member of microfilament-related formins and mediates cell motility in breast cancer (BrCa). However, the genetic mutation status of DAAM1 mRNA and its correlation with pathological characteristics are still unclearly. Methods: A patient cohort and BrCa cells were recruited to demonstrate the role of functional SNP in microRNA-208a-5p binding site of DAAM1 3′-UTR and underlying mechanism in BrCa metastasis.

Methods

A patient cohort and BrCa cells were recruited to demonstrate the role of functional SNP in microRNA-208a-5p binding site of DAAM1 3′-UTR and underlying mechanism in BrCa metastasis.

Results

The expression and activation of DAAM1 increased markedly in lymphnode metastatic tissues. A genetic variant (rs79036859 A/G) was validated in the miR-208a-5p binding site of DAAM1 3′-UTR. The G genotype (AG/GG) was a risk genotype for the metastasis of BrCa by reducing binding affinity of miR-208a-5p for the DAAM1 3′-UTR. Furthermore, the miR-208a-5p expression level was significantly suppressed in lymphnode metastatic tissues compared with that in non-lymphnode metastatic tissues. Overexpression of miR-208a-5p inhibited DAAM1/RhoA signaling pathway, thereby leading to the decrease of the migratory ability.

Conclusion

Overall, the rs79036859 G variant of DAAM1 3′-UTR was identified as a relevant role in BrCa metastasis via the diversity of miR-208a-5p binding affinity.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0747-8) contains supplementary material, which is available to authorized users.

Formins, Golgi, and the Centriole

Formin homology proteins (formins) are a highly conserved family of cytoskeletal remodeling proteins that are involved in a diverse array of cellular functions. Formins are best known for their ability to regulate actin dynamics, but the same functional domains also govern stability and organization of microtubules. It is thought that this dual activity allows them to coordinate the activity of these two major cytoskeletal networks and thereby influence cellular architecture. Golgi ribbon assembly is dependent upon cooperative interactions between actin filaments and cytoplasmic microtubules originating both at the Golgi itself and from the centrosome. Similarly, centrosome assembly, centriole duplication, and centrosome positioning are also reliant on a dialogue between both cytoskeletal networks. As presented in this chapter, a growing body of evidence suggests that multiple formin proteins play essential roles in these central cellular processes.

La-Related Protein 4 as a Suppressor for Motility of Ovarian Cancer Cells

The La-related proteins (LARPs) are a family of RNA binding proteins that control the degradation and stabilization of RNAs. As emerging research reveals the biology of each LARP, it is evident that LARPs are dysregulated in some types of cancer. Upregulation of cell motility potentiates the metastatic potential of ovarian cancer cells; however, the roles of LARPs in cell motility remain unknown. In the present study, we investigated the roles of LARPs in the progression of ovarian cancer using SKOV3 human ovarian cancer cells and a public database that integrates microarray-based gene expression data and clinical data. To explore the involvement of LARPs in the cell motility, we performed RNA interference screening for LARP mRNAs in SKOV3 cells. The screening identified LARP4 as a potential suppressor of the formation of lamellipodia. Conversely, enforced expression of LARP4 suppressed the formation of lamellipodia. Moreover, cell migration was significantly increased in LARP4-depleted SKOV3 cells. Mechanistically, LARP4 depletion was associated with the decrease in RhoA protein expression. These results suggest that LARP4 may limit RhoA-dependent cell motility. In a mouse xenograft model with SKOV3 cells, LARP4 depletion potentiated peritoneal metastasis. Upon analysis of a public database of patients with ovarian cancer, the LARP4 mRNA-high expression group (n = 166) showed longer overall survival compared with the LARP4 mRNA-low expression group (n = 489), implying a positive correlation of LARP4 mRNA levels in ovarian cancer tissues with patient prognosis. Taken together, we propose that LARP4 could suppress motility and metastatic potential of ovarian cancer cells.

Intronic miR-744 Inhibits Glioblastoma Migration by Functionally Antagonizing Its Host Gene MAP2K4

Background: The second intron of Mitogen-Activated Protein Kinase Kinase 4 (MAP2K4), an important hub in the pro-invasive MAPK pathway, harbors miR-744. There is accumulating evidence that intronic micro-RNAs (miRNAs) are capable of either supporting or restraining functional pathways of their host genes, thereby creating intricate regulative networks. We thus hypothesized that miR-744 regulates glioma migration by interacting with its host’s pathways. Methods: Patients’ tumor specimens were obtained stereotactically. MiR-744 was overexpressed in U87, T98G, and primary glioblastoma (GBM) cell lines. Cell mobility was studied using migration and Boyden chamber assays. Protein and mRNA expression was quantified by SDS-PAGE and qRT-PCR. Interactions of miR-744 and 3’UTRs were analyzed by luciferase reporter assays, and SMAD2/3, p38, and beta-Catenin activities by TOP/FOPflash reporter gene assays. Results: As compared to a normal brain, miR-744 levels were dramatically decreased in GBM samples and in primary GBM cell lines. Astrocytoma WHO grade II/III exhibited intermediate expression levels. Re-expression of miR-744 in U87, T98G, and primary GBM cell lines induced focal growth and impaired cell mobility. Luciferase activity of 3’UTR reporter constructs revealed the pro-invasive factors TGFB1 and DVL2 as direct targets of miR-744. Re-expression of miR-744 reduced levels of TGFB1, DVL2, and the host MAP2K4, and mitigated activity of TGFB1 and DVL2 downstream targets SMAD2/3 and beta-Catenin. TGFB1 knock-down repressed MAP2K4 expression. Conclusion: MiR-744 acts as an intrinsic brake on its host. It impedes MAP2K4 functional pathways through simultaneously targeting SMAD-, beta-Catenin, and MAPK signaling networks, thereby strongly mitigating pro-migratory effects of MAP2K4. MiR-744 is strongly repressed in glioma, and its re-expression might attenuate tumor invasiveness.

VOPP1 promotes breast tumorigenesis by interacting with the tumor suppressor WWOX

Background

The WW domain-containing oxidoreductase (WWOX) gene, frequently altered in breast cancer, encodes a tumor suppressor whose function is mediated through its interactions with cancer-related proteins, such as the pro-apoptotic protein p73α.

Results

To better understand the involvement of WWOX in breast tumorigenesis, we performed a yeast two-hybrid screen and co-immunoprecipitation assays to identify novel partners of this protein. We characterized the vesicular overexpressed in cancer pro-survival protein 1 (VOPP1) as a new regulator of WWOX. In breast cancer cells, VOPP1 sequestrates WWOX in lysosomes, impairs its ability to associate with p73α, and inhibits WWOX-dependent apoptosis. Overexpressed VOPP1 potentiates cellular transformation and enhances the growth of transplanted tumors in vivo. VOPP1 is overexpressed in breast tumors, especially in tumors that retain WWOX. Moreover, increased expression of VOPP1 is associated with reduced survival of patients with WWOX-positive, but not with WWOX-negative, tumors.

Conclusions

These findings emphasize the importance of the sequestration of WWOX by VOPP1 in addition to WWOX loss in breast tumors and define VOPP1 as a novel oncogene promoting breast carcinogenesis by inhibiting the anti-tumoral effect of WWOX.

Electronic supplementary material

The online version of this article (10.1186/s12915-018-0576-6) contains supplementary material, which is available to authorized users.

Integrin αvβ3-associated DAAM1 is essential for collagen-induced invadopodia extension and cell haptotaxis in breast cancer cells

The formin protein dishevelled-associated activator of morphogenesis 1 (DAAM1) polymerizes straight actin filaments and mediates migration of cancer cells. However, how DAAM1 governs cell haptotaxis in response to collagen remains unexplored in breast cancer cells. We hypothesized that DAAM1 mediates invadopodia extension and cell haptotaxis in response to type IV collagen in association with integrin receptors. Using Boyden chamber membranes coated with type IV collagen, we show here that type IV collagen activates both DAAM1 and Ras homolog family member A (RHOA) and promotes haptotaxis of MDA-MB-231 and MDA-MB-453 breast cancer cells, a process abolished by treatment with the integrin αvβ3 inhibitor cyclo(-RGDfK). shRNA-mediated knockdown of DAAM1 or a dominant-negative DAAM1 mutation (N-DAAM1) significantly decreased collagen-induced RHOA activity and the assembly of stress fibers, invadopodia extension, and cell haptotaxis. Immunoprecipitation and pulldown assays revealed that integrin αvβ3 is associated with, but only indirectly binds to, the C-terminal DAD domain of DAAM1 in mammalian cells. Blockade of RHOA activation with a specific inhibitor (CCG-1423) or via a dominant-negative RHOA mutation (RHOA-N19) suppressed collagen-induced invadopodia extension and haptotaxis of the MDA-MB-231 and MDA-MB-453 cells. Immunoblotting and immunofluorescence assays indicated high DAAM1 and RHOA expression in invadopodia, which was abolished by cyclo(-RGDfK) treatment or DAAM1 knockdown. These findings have uncovered an integrin αvβ3/DAAM1/RHOA signaling pathway for type IV collagen-induced invadopodia extension and haptotaxis in breast cancer cells. Targeting this pathway may be a means for reducing invasiveness and metastasis of breast cancer.

ARHGEF39 promotes tumor progression via activation of Rac1/P38 MAPK/ATF2 signaling and predicts poor prognosis in non-small cell lung cancer patients

Rho guanine nucleotide exchange factor 39 (ARHGEF39), also called C9orf100, is a new member of the Dbl-family of guanine nucleotide exchange factors. Although ARHGEF39 has been proven to regulate tumor progression in hepatocellular carcinoma, the downstream signaling pathway of ARHGEF39 and its clinical associations in non-small cell lung cancer (NSCLC) are currently unknown. In the present study, using MTT, colony formation, flow cytometry, mice xenografts, wound healing, and transwell assays, we showed that ARHGEF39 promoted tumor proliferation, migration, and invasion. Furthermore, ARHGEF39 promoted the expression of Cyclin A2, Cyclin D1, and MMP2 by activating Rac1, leading to increased phosphorylation of P38 and ATF2. Treatment with a P38 inhibitor counteracted the effect of ARHGEF39 overexpression on the increase in Cyclin A2, Cyclin D1, and MMP2 expression. Moreover, the elevated levels of p-P38 and p-ATF2 caused by ARHGEF39 overexpression could be inhibited by expression of a dominant negative Rac1 mutant (T17N). In addition, the inhibition of the expression of p-P38 and p-ATF2 by ARHGEF39 RNAi could be restored by the expression of a constitutively active Rac1 mutant (Q61L). A similar impact on cell growth and invasion was observed after ARHGEF39 overexpression combined with the P38 inhibitor, Rac1 T17N, or Rac1 Q61L. Using immunohistochemistry, ARHGEF39 expression was observed to correlate positively with larger tumor size in clinical samples from 109 cases of NSCLC (P = 0.008). The Kaplan-Meier test revealed that ARHGEF39 expression significantly affected the overall survival of patients with NSCLC (52.55 ± 6.40 months vs. 64.30 ± 5.40 months, P = 0.017). In conclusion, we identified that ARHGEF39 promotes tumor growth and invasion by activating the Rac1-P38-ATF2 signaling pathway, as well as increasing the expression of Cyclin A2, Cyclin D1, and MMP2 in NSCLC cells. ARHGEF39 may be a useful marker to predict poor prognosis of patients with NSCLC.

Wnt5a-induced cell migration is associated with the aggressiveness of estrogen receptor-positive breast cancer

Elevated expression of Wnt5a is associated with malignancy, cell invasion, and metastasis. The role of Wnt5a expression in breast cancer remains elusive. We investigated the significance of Wnt5a expression in breast cancer. The relationship between Wnt5a expression and clinicopathologic factors was assessed in invasive breast cancer (n = 178) resected at Hiroshima University Hospital between January 2011 and February 2014. Wnt5a was expressed in 69 of 178 cases (39%) of invasive breast cancer and correlated strongly with estrogen receptor (ER) expression (P < 0.001). Wnt5a expression in ER-positive breast cancer correlated significantly with lymph node metastasis, nuclear grade, and lymphatic invasion. The recurrence-free survival was shorter in breast cancer patients with Wnt5a expression than in those without (P = 0.024). The migratory capacity of ER-positive breast cancer cells increased with constitutive expression of Wnt5a and decreased with Wnt5a knockdown. DNA microarray analysis identified activated leukocyte cell adhesion molecule (ALCAM) as the primary gene induced by Wnt5a. ALCAM was expressed in 69% of Wnt5a-positive but only 27% of Wnt5a-negative cancers (κ = 0.444; P < 0.001). The inhibition of ALCAM reversed the enhanced migratory effect of Wnt5a, confirming the importance of this protein in the migration of ER-positive breast cancer cells. Wnt5a expression is related to high malignancy and a poor prognosis in ER-positive breast cancer. We suspect that Wnt5a expression increases the malignancy of breast cancer by increasing the migratory capacity of cancer cells through the induction of ALCAM expression.

Wnt5a and CCL25 promote adult T-cell acute lymphoblastic leukemia cell migration, invasion and metastasis

Adult T-cell acute lymphoblastic leukemia (T-ALL) is a refractory leukemia. We previously showed that CCL25/CCR9 promotes T-ALL metastasis. In the present study, we assessed the effects of CCL25 on Wnt expression and the effects of Wnt5a and CCL25 on PI3K/Akt and RhoA activation. Transwell assays and mouse xenograft experiments were utilized to assess the effects of Wnt5a and CCL25 on MOLT4 cell invasion, migration and metastasis. The effects of Wnt5a on MOLT4 cell actin polarization and pseudopodium formation were examined using laser scanning confocal microscopy and scanning electron microscopy. CCL25 induced Wnt5a expression in MOLT4 cells by promoting protein kinase C (PKC) expression and activation. Wnt5a promoted MOLT4 cell migration, invasion, actin polarization, and lamellipodium and filopodia formation via PI3K/Akt-RhoA pathway activation. These effects were rescued by PI3K/Akt or RhoA knockdown or inhibition. Additionally, Wnt5a in cooperation with CCL25 promoted MOLT4 cell mouse liver metastasis and stimulated RhoA activation. These results show that CCL25/CCR9 upregulates Wnt5a by promoting PKC expression and activation in MOLT4 cells. This in turn promotes cell migration and invasion via PI3K/Akt-RhoA signaling, enhancing cell polarization and pseudopodium formation. These findings indicate that the PI3K/Akt-RhoA pathway is likely responsible for Wnt5a-induced adult T-ALL cell migration and invasion.

A global transcriptional network connecting noncoding mutations to changes in tumor gene expression

Although cancer genomes are replete with noncoding mutations, the effects of these mutations remain poorly characterized. Here we perform an integrative analysis of 930 tumor whole genomes and matched transcriptomes, identifying a network of 193 noncoding loci in which mutations disrupt target gene expression. These “somatic eQTLs” (expression Quantitative Trait Loci) are frequently mutated in specific cancer tissues, and the majority can be validated in an independent cohort of 3,382 tumors. Among these, we find that the effects of noncoding mutations on DAAM1, MTG2 and HYI transcription are recapitulated in multiple cancer cell lines, and that increasing DAAM1 expression leads to invasive cell migration. Collectively the noncoding loci converge on a set of core pathways, permitting a classification of tumors into pathway-based subtypes. The somatic eQTL network is disrupted in 88% of tumors, suggesting widespread impact of noncoding mutations in cancer.

A Boolean network of the crosstalk between IGF and Wnt signaling in aging satellite cells

Aging is a complex biological process, which determines the life span of an organism. Insulin-like growth factor (IGF) and Wnt signaling pathways govern the process of aging. Both pathways share common downstream targets that allow competitive crosstalk between these branches. Of note, a shift from IGF to Wnt signaling has been observed during aging of satellite cells. Biological regulatory networks necessary to recreate aging have not yet been discovered. Here, we established a mathematical in silico model that robustly recapitulates the crosstalk between IGF and Wnt signaling. Strikingly, it predicts critical nodes following a shift from IGF to Wnt signaling. These findings indicate that this shift might cause age-related diseases.