BRMS1L suppresses breast cancer metastasis by inducing epigenetic silence of FZD10

Frizzled receptors (FZDs) in Wnt signaling: potential therapeutic targets for human cancers

Frizzled receptors (FZDs) are key contributors intrinsic to the Wnt signaling pathway, activation of FZDs triggering the Wnt signaling cascade is frequently observed in human tumors and intimately associated with an aggressive carcinoma phenotype. It has been shown that the abnormal expression of FZD receptors contributes to the manifestation of malignant characteristics in human tumors such as enhanced cell proliferation, metastasis, chemotherapy resistance as well as the acquisition of cancer stemness. Given the essential roles of FZD receptors in the Wnt signaling in human tumors, this review aims to consolidate the prevailing knowledge on the specific status of FZD receptors (FZD1-10) and elucidate their respective functions in tumor progression. Furthermore, we delineate the structural basis for binding of FZD and its co-receptors to Wnt, and provide a better theoretical foundation for subsequent studies on related mechanisms. Finally, we describe the existing biological classes of small molecule-based FZD inhibitors in detail in the hope that they can provide useful assistance for design and development of novel drug candidates targeted FZDs.

An update on existing therapeutic options and status of novel anti-metastatic agents in breast cancer: Elucidating the molecular mechanisms underlying the pleiotropic action of Withania somnifera (Indian ginseng) in breast cancer attenuation

Major significant advancements in pharmacology and drug technology have been made to heighten the impact of cancer therapies, improving the life expectancy of subjects diagnosed with malignancy. Statistically, 99% of breast cancers occur in women while 0.5-1% occur in men, the female gender being the strongest breast cancer risk factor. Despite several breakthroughs, breast cancer continues to have a worldwide impact and is one of the leading causes of mortality. Additionally, resistance to therapy is a crucial factor enabling cancer cell persistence and resurgence. As a result, the search and discovery of novel modulatory agents and effective therapies capable of controlling tumor progression and cancer cell proliferation is critical. Withania somnifera (L.) Dunal (WS), commonly known as Indian ginseng, has long been used traditionally for the treatment of several ailments in the Indian context. Recently, WS and its phytoconstituents have shown promising anti-breast cancer properties and, as such, can be employed as prophylactic as well as therapeutic adjuncts to the main line of breast cancer treatment. The present review is an attempt to explore and provide experimental evidences in support of the prophylactic and therapeutic potential of WS in breast cancer, along with a deeper insight into the multiple molecular mechanisms and novel targets through which it acts against breast and other hormonally-induced cancers viz. ovarian, uterine and cervical. This exploration might prove crucial in providing better understanding of breast cancer progression and metastasis and its use as an adjunct in improving disease prognosis and therapeutic outcome.

A novel fatty acid metabolism-related signature identifies MUC4 as a novel therapy target for esophageal squamous cell carcinoma

Fatty acid metabolism has been identified as an emerging hallmark of cancer, which was closely associated with cancer prognosis. Whether fatty acid metabolism-related genes (FMGs) signature play a more crucial role in biological behavior of esophageal squamous cell carcinoma (ESCC) prognosis remains unknown. Thus, we aimed to identify a reliable FMGs signature for assisting treatment decisions and prognosis evaluation of ESCC. In the present study, we conducted consensus clustering analysis on 259 publicly available ESCC samples. The clinical information was downloaded from The Cancer Genome Atlas (TCGA, 80 ESCC samples) and Gene Expression Omnibus (GEO) database (GSE53625, 179 ESCC samples). A consensus clustering arithmetic was used to determine the FMGs molecular subtypes, and survival outcomes and immune features were evaluated among the different subtypes. Kaplan-Meier analysis and the receiver operating characteristic (ROC) was applied to evaluate the reliability of the risk model in training cohort, validation cohort and all cohorts. A nomogram to predict patients' 1-year, 3-year and 5-year survival rate was also studied. Finally, CCK-8 assay, wound healing assay, and transwell assay were implemented to evaluate the inherent mechanisms of FMGs for tumorigenesis in ESCC. Two subtypes were identified by consensus clustering, of which cluster 2 is preferentially associated with poor prognosis, lower immune cell infiltration. A fatty acid (FA) metabolism-related risk model containing eight genes (FZD10, TACSTD2, MUC4, PDLIM1, PRSS12, BAALC, DNAJA2 and ALOX12B) was established. High-risk group patients displayed worse survival, higher stromal, immune and ESTIMATE scores than in the low-risk group. Moreover, a nomogram revealed good predictive ability of clinical outcomes in ESCC patients. The results of qRT-PCR analysis revealed that the MUC4 and BAALC had high expression level, and FZD10, PDLIM1, TACSTD2, ALOX12B had low expression level in ESCC cells. In vitro, silencing MUC4 remarkably inhibited ESCC cell proliferation, invasion and migration. Our study fills the gap of FMGs signature in predicting the prognosis of ESCC patients. These findings revealed that cluster subtypes and risk model of FMGs had effects on survival prediction, and were expected to be the potential promising targets for ESCC.

DNMT3A-mediated DNA methylation and transcription inhibition of FZD5 suppresses lung carcinogenesis

Background

Based on the bioinformatics prediction, this study investigates the correlation between aberrant transcription factor Frizzled 5 (FZD5) expression and the establishment of non-small cell lung cancer (NSCLC).

Methods

A mouse model with regard to primary NSCLC was encouraged by intraperitoneal injection of urethane. Lentivirus-based FZD5 silencing was then administrated to examine its role in tumorigenesis in the mouse lung. Silencing of FZD5 was induced in two NSCLC cell lines to examine its function in the malignant behavior pertaining to cells in vitro. Quantitative methylation-specific PCR was employed to assess the DNA methylation level within the NSCLC cells. DNA methyltransferases (DNMTs) that administer FZD5 were assessed by chromatin immunoprecipitation assay. Consequently, overexpression of DNMT3A was introduced in mice and NSCLC cells to verify its regulation on FZD and its biological roles in NSCLC development.

Results

In NSCLC, FZD5 expression is elevated, and its knockdown reduced tumor incidence rate in the urethane-challenged mice. The FZD5 silencing also inhibited proliferation, migration, as well as invasion with regard to Calu-3 and NCI-H1299 cells in vitro. The aberrant upregulation with regard to FZD5 in NSCLC was due to at least partly by reduced promoter methylation level. DNMT3A, which bound to FZD5 promoter to suppress its transcription, was poorly expressed in NSCLC. Artificial upregulation of DNMT3A suppressed urethane-induced lung carcinogenesis in mice and suppressed the malignant phenotype pertaining to NSCLC cells in vitro.

Conclusion

This research demonstrates that the lack of DNA methylation level-induced activation of FZD5 is correlated with NSCLC's onset and progression.

Epidemiological and Genetic Analyses of Schizophrenia and Breast Cancer

BACKGROUND AND HYPOTHESIS

While the phenotypic association between schizophrenia and breast cancer has been observed, the underlying intrinsic link is not adequately understood. We aim to conduct a comprehensive interrogation on both phenotypic and genetic relationships between schizophrenia and breast cancer.

STUDY DESIGN

We first used data from UK Biobank to evaluate a phenotypic association and performed an updated meta-analysis incorporating existing cohort studies. We then leveraged genomic data to explore the shared genetic architecture through a genome-wide cross-trait design.

STUDY RESULTS

Incorporating results of our observational analysis, meta-analysis of cohort studies suggested a significantly increased incidence of breast cancer among women with schizophrenia (RR = 1.30, 95% CIs = 1.14-1.48). A positive genomic correlation between schizophrenia and overall breast cancer was observed (rg = 0.12, P = 1.80 × 10-10), consistent across ER+ (rg  = 0.10, P = 5.74 × 10-7) and ER- subtypes (rg = 0.09, P = .003). This was further corroborated by four local signals. Cross-trait meta-analysis identified 23 pleiotropic loci between schizophrenia and breast cancer, including five novel loci. Gene-based analysis revealed 27 shared genes. Mendelian randomization demonstrated a significantly increased risk of overall breast cancer (OR = 1.07, P = 4.81 × 10-10) for genetically predisposed schizophrenia, which remained robust in subgroup analysis (ER+: OR = 1.10, P = 7.26 × 10-12; ER-: OR = 1.08, P = 3.50 × 10-6). No mediation effect and reverse causality was found.

CONCLUSIONS

Our study demonstrates an intrinsic link underlying schizophrenia and breast cancer, which may inform tailored screening and management of breast cancer in schizophrenia.

BRMS1L confers anticancer activity in non-small cell lung cancer by transcriptionally inducing a redox imbalance in the GPX2-ROS pathway

Low expression levels of breast cancer metastasis suppressor 1 like (BRMS1L) have been associated with the growth of cancer cells. However, the mechanisms underlying the role of BRMS1L as an antitumour transcription factor in the progression of NSCLC have not been explored. Herein, we reveal that BRMS1L plays a key role as a tumour suppressor in inhibiting NSCLC proliferation and metastasis. Mechanistically, BRMS1L overexpression results in the downregulation of glutathione peroxidase 2 (GPX2) expression and consequently causes abnormal glutathione metabolism and increased levels of reactive oxygen species (ROS) in cells, inducing oxidative stress injury and apoptosis. Furthermore, overexpression of GPX2 enhances the growth advantage and oxidative stress repair conferred by knockdown of BRMS1L. Importantly, we show that low expression of BRMS1L in NSCLC cells causes relatively high levels of antioxidant accumulation to maintain cell redox balance and renders cancer cells more sensitive to treatment with piperlongumine as an ROS inducer both in vitro and in vivo. These findings offer new insights into the role of BRMS1L as a transcriptional repressor in NSCLC and suggest that the BRMS1L expression level may be a potential biomarker for predicting the therapeutic response to small molecule ROS inducers, providing new ideas for targeted therapy.

Metastasis suppressor genes in clinical practice: are they druggable?

Since the identification of NM23 (now called NME1) as the first metastasis suppressor gene (MSG), a small number of other gene products and non-coding RNAs have been identified that suppress specific parameters of the metastatic cascade, yet which have little or no ability to regulate primary tumor initiation or maintenance. MSG can regulate various pathways or cell biological functions such as those controlling mitogen-activated protein kinase pathway mediators, cell-cell and cell-extracellular matrix protein adhesion, cytoskeletal architecture, G-protein-coupled receptors, apoptosis, and transcriptional complexes. One defining facet of this gene class is that their expression is typically downregulated, not mutated, in metastasis, such that any effective therapeutic intervention would involve their re-expression. This review will address the therapeutic targeting of MSG, once thought to be a daunting task only facilitated by ectopically re-expressing MSG in metastatic cells in vivo. Examples will be cited of attempts to identify actionable oncogenic pathways that might suppress the formation or progression of metastases through the re-expression of specific metastasis suppressors.

Upregulation of SOX9 promotes the self-renewal and tumorigenicity of cervical cancer through activating the Wnt/β-catenin signaling pathway

Sry-box9 (SOX9) maintains stem cell properties and plays crucial roles in many cancers. However, whether SOX9 is correlated with cervical cancer cell stemness and its detailed mechanism remains obscure. We studied the relationship between SOX9 and prognosis of cervical cancer through public database, and SOX9 was related to poor prognosis of cervical cancer. Elevated SOX9 expression enhanced the self-renewal properties and promotes tumorigenicity in cervical cancer. Overexpression of SOX9 could promote the expression of stem cell-related factors in cervical cancer cells and xenografts. Meanwhile, overexpression of SOX9 could also enhance the expressions of FZD10, β-catenin, and c-Myc in cervical cancer cells and xenografts, while inhibiting the expression of DDK1. The activation of Wnt pathway by chir-99 021 raised the tumor spheroid ability of SOX9 knockdown HeLa cells. In addition, SOX9 could transcriptional inhibit DKK1 and activate FZD10 and MYC by binding to their promoters to affect the Wnt/β-catenin pathway. These results demonstrated SOX9 regulated the self-renewal and tumorigenicity of cervical cancer through Wnt/β-catenin pathway by directly transcriptional activation of FZD10, MYC and transcriptional inhibition of DKK1.

Bta-miR-106b Regulates Bovine Mammary Epithelial Cell Proliferation, Cell Cycle, and Milk Protein Synthesis by Targeting the CDKN1A Gene

Our previous studies found that bta-miR-106b and its corresponding target gene, CDKN1A, were differentially expressed between the mammary epithelium of lactating Holstein cows with extremely high and low milk protein and fat percentage, implying the potential role of bta-miR-106b in milk composition synthesis. In this study, with luciferase assay experiment, bta-miR-106b was validated to target the 3'-untranslated region (UTR) of bovine CDKN1A, thereby regulating its expression. Moreover, in bovine mammary epithelial cells (BMECs), over-expression of bta-miR-106b significantly down-regulated the CDKN1A expression at both mRNA and protein levels, and inhibitors of bta-miR-106b increased CDKN1A expression. Of note, we observed that bta-miR-106b accelerated cell proliferation and cell cycle, and changed the expressions of protein synthesis related pathways such as JAK-STAT and PI3K/AKT/mTOR through regulating CDKN1A expression. Our findings highlight the important regulatory role of bta-miR-106b in milk protein synthesis by targeting CDKN1A in dairy cattle.

Caveolin-1 signaling-driven mitochondrial fission and cytoskeleton remodeling promotes breast cancer migration

Mitochondria are highly dynamic organelles that constantly divide and fuse to maintain their proper structure and function. Cancer cells are often accompanied by an imbalance of mitochondrial fusion and fission, cancer progression is greatly affected by this imbalance. Here, we found that high-metastatic breast cancer MDA-MB-231 cells possess higher caveolin-1 (Cav-1) expression compared with low-metastatic breast cancer MCF-7 cells or normal breast epithelial MCF-10A cells. Downregulation of Cav-1 decreases the migratory and invasive abilities of MDA-MB-231 cells. Our results further demonstrated that downregulation of Cav-1 facilitated DRP1 and MFN2 to translocate to mitochondria, increasing the inhibitory phosphorylation level of DRP1 at Ser637 by protein kinase A (PKA), resulting in mitochondria elongation. We also showed that downregulation of Cav-1 significantly reduced the Rac1 activity by affecting intracellular reactive oxygen species (ROS) generation, which then inhibited F-actin formation. Based on these findings, we proposed that Cav-1 mediated mitochondrial fission-affected intracellular ROS generation and activated Rho GTPases, leading to F-actin-dependent formation of lamellipodia and promotion of breast cancer motility.

Epigenetics and environment in breast cancer: New paradigms for anti-cancer therapies

Breast cancer remains the most frequently diagnosed cancer in women worldwide. Delayed presentation of the disease, late stage at diagnosis, limited therapeutic options, metastasis, and relapse are the major factors contributing to breast cancer mortality. The development and progression of breast cancer is a complex and multi-step process that incorporates an accumulation of several genetic and epigenetic alterations. External environmental factors and internal cellular microenvironmental cues influence the occurrence of these alterations that drives tumorigenesis. Here, we discuss state-of-the-art information on the epigenetics of breast cancer and how environmental risk factors orchestrate major epigenetic events, emphasizing the necessity for a multidisciplinary approach toward a better understanding of the gene-environment interactions implicated in breast cancer. Since epigenetic modifications are reversible and are susceptible to extrinsic and intrinsic stimuli, they offer potential avenues that can be targeted for designing robust breast cancer therapies.

Personalized 3-Gene Panel for Prostate Cancer Target Therapy

Many years and billions spent for research did not yet produce an effective answer to prostate cancer (PCa). Not only each human, but even each cancer nodule in the same tumor, has unique transcriptome topology. The differences go beyond the expression level to the expression control and networking of individual genes. The unrepeatable heterogeneous transcriptomic organization among men makes the quest for universal biomarkers and “fit-for-all” treatments unrealistic. We present a bioinformatics procedure to identify each patient’s unique triplet of PCa Gene Master Regulators (GMRs) and predict consequences of their experimental manipulation. The procedure is based on the Genomic Fabric Paradigm (GFP), which characterizes each individual gene by the independent expression level, expression variability and expression coordination with each other gene. GFP can identify the GMRs whose controlled alteration would selectively kill the cancer cells with little consequence on the normal tissue. The method was applied to microarray data on surgically removed prostates from two men with metastatic PCas (each with three distinct cancer nodules), and DU145 and LNCaP PCa cell lines. The applications verified that each PCa case is unique and predicted the consequences of the GMRs’ manipulation. The predictions are theoretical and need further experimental validation.

A Capped Tudor Domain within a Core Subunit of the Sin3L/Rpd3L Histone Deacetylase Complex Binds to Nucleic Acid G-Quadruplexes

Chromatin-modifying complexes containing histone deacetylase (HDAC) activities play critical roles in the regulation of gene transcription in eukaryotes. These complexes are thought to lack intrinsic DNA-binding activity, but according to a well-established paradigm, they are recruited via protein–protein interactions by gene-specific transcription factors and posttranslational histone modifications to their sites of action on the genome. The mammalian Sin3L/Rpd3L complex, comprising more than a dozen different polypeptides, is an ancient HDAC complex found in diverse eukaryotes. The subunits of this complex harbor conserved domains and motifs of unknown structure and function. Here, we show that Sds3, a constitutively-associated subunit critical for the proper functioning of the Sin3L/Rpd3L complex, harbors a type of Tudor domain that we designate the capped Tudor domain. Unlike canonical Tudor domains that bind modified histones, the Sds3 capped Tudor domain binds to nucleic acids that can form higher-order structures such as G-quadruplexes and shares similarities with the knotted Tudor domain of the Esa1 histone acetyltransferase that was previously shown to bind single-stranded RNA. Our findings expand the range of macromolecules capable of recruiting the Sin3L/Rpd3L complex and draw attention to potentially new biological roles for this HDAC complex.

JAM2 predicts a good prognosis and inhibits invasion and migration by suppressing EMT pathway in breast cancer

OBJECTIVES

Large-scale epidemiological surveys have shown that patients with Down syndrome, which is caused by a chromosomal abnormality (an extra chromosome 21), are significantly less likely to develop solid tumors, including breast cancer, than those without. This feature has prompted the search for oncogenes located on chromosome 21. Junctional adhesion molecule 2 (JAM2), which is located on chromosome 21, is expressed at low levels in breast cancer and is associated with a good prognosis. These findings strongly suggest that JAM2 may be a potential oncogene suppressor in breast cancer. However, the role and function of JAM2 in breast cancer are not yet clear. Therefore, this study aimed to explore the biological functions and mechanisms of JAM2 in breast cancer.

METHODS

Several databases were used to explore JAM2 expression in breast cancer and to analyze its diagnostic and prognostic value in breast cancer. Changes in relevant markers were examined at the gene and protein levels using RT-qPCR and Western blot techniques, in addition, cell migration and invasion abilities were identified by scratch assays and transwell assays. Untargeted metabolomics, transcriptome sequencing and Luminex liquid suspension chip detection were performed in combination to study the mechanisms.

RESULTS

JAM2 is expressed at low levels in breast cancer, and patients with high JAM2 expression have a good prognosis, indicating that JAM2 has good clinical diagnostic and prognostic value. Overexpression of JAM2 can block the invasion and migration of breast cancer cells, and the mechanism may be that JAM2 inhibits the EMT pathway. Finally, combined multiomics analysis revealed that JAM2 may affect the immune microenvironment of breast cancer by influencing the secretion of CXCL9/10 from tumor cells.

A Co-Association Network Analysis Reveals Putative Regulators for Health-Related Traits in Pigs

In recent years, the increase in awareness of antimicrobial resistance together with the societal demand of healthier meat products have driven attention to health-related traits in livestock production. Previous studies have reported medium to high heritabilities for these traits and described genomic regions associated with them. Despite its genetic component, health- and immunity-related traits are complex and its study by association analysis with genomic markers may be missing some information. To analyse multiple phenotypes and gene-by-gene interactions, systems biology approaches, such as the association weight matrix (AWM), allows combining genome wide association study results with network inference algorithms. The present study aimed to identify gene networks, key regulators and candidate genes associated to immunocompetence in pigs by integrating multiple health-related traits, enriched for innate immune phenotypes, using the AWM approach. The co-association network analysis unveiled a network comprised of 3,636 nodes (genes) and 451,407 edges (interactions), including a total of 246 regulators. From these, five genes (ARNT2, BRMS1L, MED12L, SUPT3H and TRIM25) were selected as key regulators as they were associated with the maximum number of genes with the minimum overlapping (1,827 genes in total). The five regulators were involved in pathways related to immunity such as lymphocyte differentiation and activation, platelet activation and degranulation, megakaryocyte differentiation, FcγR-mediated phagocytosis and response to nitric oxide, among others, but also in immunometabolism. Furthermore, we identified genes co-associated with the key regulators previously reported as candidate genes (e.g., ANGPT1, CD4, CD36, DOCK1, PDE4B, PRKCE, PTPRC and SH2B3) for immunity traits in humans and pigs, but also new candidate ones (e.g., ACSL3, CXADR, HBB, MMP12, PTPN6, WLS) that were not previously described. The co-association analysis revealed new regulators associated with health-related traits in pigs. This approach also identified gene-by-gene interactions and candidate genes involved in pathways related to cell fate and metabolic and immune functions. Our results shed new light in the regulatory mechanisms involved in pig immunity and reinforce the use of the pig as biomedical model.

Competitive Endogenous RNA Landscape in Epstein-Barr Virus Associated Nasopharyngeal Carcinoma

Non-coding RNAs have been shown to play important regulatory roles, notably in cancer development. In this study, we investigated the role of microRNAs and circular RNAs in Nasopharyngeal Carcinoma (NPC) by constructing a circRNA-miRNA-mRNA co-expression network and performing differential expression analysis on mRNAs, miRNAs, and circRNAs. Specifically, the Epstein-Barr virus (EBV) infection has been found to be an important risk factor for NPC, and potential pathological differences may exist for EBV+ and EBV- subtypes of NPC. By comparing the expression profile of non-cancerous immortalized nasopharyngeal epithelial cell line and NPC cell lines, we identified differentially expressed coding and non-coding RNAs across three groups of comparison: cancer vs. non-cancer, EBV+ vs. EBV- NPC, and metastatic vs. non-metastatic NPC. We constructed a ceRNA network composed of mRNAs, miRNAs, and circRNAs, leveraging co-expression and miRNA target prediction tools. Within the network, we identified the regulatory ceRNAs of CDKN1B, ZNF302, ZNF268, and RPGR. These differentially expressed axis, along with other miRNA-circRNA pairs we identified through our analysis, helps elucidate the genetic and epigenetic changes central to NPC progression, and the differences between EBV+ and EBV- NPC.

Perturbation of BRMS1 interactome reveals pathways that impact metastasis

Breast Cancer Metastasis Suppressor 1 (BRMS1) expression is associated with longer patient survival in multiple cancer types. Understanding BRMS1 functionality will provide insights into both mechanism of action and will enhance potential therapeutic development. In this study, we confirmed that the C-terminus of BRMS1 is critical for metastasis suppression and hypothesized that critical protein interactions in this region would explain its function. Phosphorylation status at S237 regulates BRMS1 protein interactions related to a variety of biological processes, phenotypes [cell cycle (e.g., CDKN2A), DNA repair (e.g., BRCA1)], and metastasis [(e.g., TCF2 and POLE2)]. Presence of S237 also directly decreased MDA-MB-231 breast carcinoma migration in vitro and metastases in vivo. The results add significantly to our understanding of how BRMS1 interactions with Sin3/HDAC complexes regulate metastasis and expand insights into BRMS1's molecular role, as they demonstrate BRMS1 C-terminus involvement in distinct protein-protein interactions.

ARID1A Mutation in Metastatic Breast Cancer: A Potential Therapeutic Target

Distant metastasis is the principal cause of mortality for breast cancer patients. Targeting specific mutations that have been acquired during the evolution process of advanced breast cancer is a potential means of enhancing the clinical efficacy of treatment strategies. In metastatic breast cancer, ARID1A is the most prevalent mutation of the SWI/SNF complex, which regulates DNA repair, recombination, and gene transcription. The low expression of ARID1A is associated with poor disease-free survival and overall survival of patients with luminal A or HER2-rich breast cancer. In addition, ARID1A plays a prominent role in maintaining luminal characteristics and has an advantage for identifying responses to treatment, including endocrine therapies, HDAC inhibitors and CDK4/6 inhibitors. The therapeutic vulnerabilities initiated by ARID1A alterations encourage us to explore new approaches to cope with ARID1A mutant-related drug resistance or metastasis. In this review, we describe the mutation profiles of ARID1A in metastatic breast cancer and the structure and function of ARID1A and the SWI/SNF complex as well as discuss the potential mechanisms of ARID1A-mediated endocrine resistance and therapeutic potential.

LncRNA-SNHG1 promotes macrophage M2-like polarization and contributes to breast cancer growth and metastasis

Breast cancer is one of the most common malignant cancers among women. Cancer cells and adjacent cells determine the development of the disease. Tumor associated macrophages (TAMs) are involved in the regulation of different stages of cancer progression. LncRNAs play an important role in tumor growth and metastasis. However, the function of lncRNA in macrophage and tumor cell interaction is poorly described. Here we reported that lncRNA SNHG1 functioned as a modulator of M2 macrophage polarization and regulated tumor growth and angiogenesis. We indicated that knockdown of SNHG1 inhibited M2 macrophage polarization by suppression of STAT6 phosphorylation. SNHG1 silencing significantly alleviated migration of MCF-7 cells and tube formation of Human Umbilical Vein Endothelial Cells (HUVEC). Furthermore, we found that implantation of cell mixture of MCF-7 cells and macrophages promoted tumor growth and angiogenesis. However, knockdown of SNHG1 in macrophages reversed that effect. Collectively, we demonstrated the important role of lncRNA SNHG1 in macrophages and breast cancer cells interaction. We highlight the essential effect of lncRNA in tumor progression and provide a new method for the prevention and treatment of breast tumor metastasis.

Non-Coding RNA and Frizzled Receptors in Cancer

Frizzled receptors have been long recognized for their role in Wnt/β-catenin signaling, a pathway known for its tumorigenic effects. More recent studies of frizzled receptors include efforts to understand non-coding RNA (ncRNA) regulation of these receptors in cancer. It has become increasingly clear that ncRNA molecules are important for regulating the expression of both oncogenic and tumor-suppressive proteins. The three most commonly described ncRNA molecules are microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Here, we review ncRNA molecules that directly or indirectly affect frizzled protein expression and downstream signaling. Exploring these interactions highlights the potential of incorporating ncRNA molecules into cancer prevention and therapy strategies that target frizzled receptors. Previous investigations of frizzled receptors and ncRNA have established strong promise for a role in cancer progression, but additional studies are needed to provide the substantial pre-clinical evidence required to translate findings to clinical applications.

Targeting Histone Modifications in Breast Cancer: A Precise Weapon on the Way

Histone modifications (HMs) contribute to maintaining genomic stability, transcription, DNA repair, and modulating chromatin in cancer cells. Furthermore, HMs are dynamic and reversible processes that involve interactions between numerous enzymes and molecular components. Aberrant HMs are strongly associated with tumorigenesis and progression of breast cancer (BC), although the specific mechanisms are not completely understood. Moreover, there is no comprehensive overview of abnormal HMs in BC, and BC therapies that target HMs are still in their infancy. Therefore, this review summarizes the existing evidence regarding HMs that are involved in BC and the potential mechanisms that are related to aberrant HMs. Moreover, this review examines the currently available agents and approved drugs that have been tested in pre-clinical and clinical studies to evaluate their effects on HMs. Finally, this review covers the barriers to the clinical application of therapies that target HMs, and possible strategies that could help overcome these barriers and accelerate the use of these therapies to cure patients.

Epigenetic Regulation of the Wnt/β-Catenin Signaling Pathway in Cancer

Studies over the past four decades have elucidated the role of Wnt/β-catenin mediated regulation in cell proliferation, differentiation and migration. These processes are fundamental to embryonic development, regeneration potential of tissues, as well as cancer initiation and progression. In this review, we focus on the epigenetic players which influence the Wnt/β-catenin pathway via modulation of its components and coordinated regulation of the Wnt target genes. The role played by crosstalk with other signaling pathways mediating tumorigenesis is also elaborated. The Hippo/YAP pathway is particularly emphasized due to its extensive crosstalk via the Wnt destruction complex. Further, we highlight the recent advances in developing potential therapeutic interventions targeting the epigenetic machinery based on the characterization of these regulatory networks for effective treatment of various cancers and also for regenerative therapies.

Cancer chemoprevention through Frizzled receptors and EMT

Frizzled (FZD) transmembrane receptors are well known for their role in β-catenin signaling and development and now understanding of their role in the context of cancer is growing. FZDs are often associated with the process of epithelial to mesenchymal transition (EMT) through β-catenin, but some also influence EMT through non-canonical pathways. With ten different FZDs, there is a wide range of activity from oncogenic to tumor suppressive depending on the tissue context. Alterations in FZD signaling can occur during development of premalignant lesions, supporting their potential as targets of chemoprevention agents. Agonizing or antagonizing FZD activity may affect EMT, which is a key process in lesion progression often targeted by chemoprevention agents. Recent studies identified a specific FZD as important for activity of an EMT inhibiting chemopreventive agent and other studies have highlighted the previously unrecognized potential for targeting small molecules to FZD receptors. This work demonstrates the value of investigating FZDs in chemoprevention and here we provide a review of FZDs in cancer EMT and their potential as chemoprevention targets.

Long Noncoding RNA HCG11 Acts as a Tumor Suppressor in Gastric Cancer by Regulating miR-942-5p/BRMS1 Axis

The functions of long noncoding RNAs (lncRNAs) have been widely investigated in human cancers, including gastric cancer (GC). The purpose of this study was to elucidate the role of lncRNA HCG11 in GC. In this study, mRNA and protein expressions were detected by quantitative real-time polymerase chain reaction assays (RT-qPCR) and Western blot analysis. The proliferation ability of GC cells was examined by (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl Tetrazolium Bromide) MTT assays. The invasion and migration abilities of GC cells were evaluated by Transwell assays. The binding sites between miR-942-5p and HCG11/BRMS1 were confirmed by dual-luciferase reporter assays. Results showed that LncRNA HCG11 was downregulated in GC cells. Functionally, overexpression of HCG11 inhibited GC cell proliferation, migration, and invasion. In addition, lncRNA HCG11 was found to act as a molecular sponge of miR-942-5p. Furthermore, miR-942-5p promoted GC progression by suppressing lncRNA HCG11 expression. Besides that, BRMS1 was confirmed as a direct target of miR-942-5p. More importantly, breast cancer metastasis suppressor 1 (BRMS1) inhibited GC progression by upregulating lncRNA HCG11 and downregulating miR-942-5p. In conclusion, LncRNA HCG11 inhibited cell proliferation, migration, and invasion in GC by sponging miR-942-5p and upregulating BRMS1.

FZD5 prevents epithelial-mesenchymal transition in gastric cancer

Background

Frizzled (FZD) proteins function as receptors for WNT ligands. Members in FZD family including FZD2, FZD4, FZD7, FZD8 and FZD10 have been demonstrated to mediate cancer cell epithelial-mesenchymal transition (EMT).

Methods

CCLE and TCGA databases were interrogated to reveal the association of FZD5 with EMT. EMT was analyzed by investigating the alterations in CDH1 (E-cadherin), VIM (Vimentin) and ZEB1 expression, cell migration and cell morphology. Transcriptional modulation was determined by ChIP in combination with Real-time PCR. Survival was analyzed by Kaplan–Meier method.

Results

In contrast to other FZDs, FZD5 was identified to prevent EMT in gastric cancer. FZD5 maintains epithelial-like phenotype and is negatively modulated by transcription factors SNAI2 and TEAD1. Epithelial-specific factor ELF3 is a downstream effecter, and protein kinase C (PKC) links FZD5 to ELF3. ELF3 represses ZEB1 expression, further guarding against EMT. Moreover, FZD5 signaling requires its co-receptor LRP5 and WNT7B is a putative ligand for FZD5. FZD5 and ELF3 are associated with longer survival, whereas SNAI2 and TEAD1 are associated with shorter survival.

Conclusions

Taken together, FZD5-ELF3 signaling blocks EMT, and plays a potential tumor-suppressing role in gastric cancer.

Transcriptome analysis of arterial and venous circulating miRNAs during hypertension

Most current circulating miRNA biomarkers are derived from peripheral venous blood, whereas miRNA deregulation in arterial blood in disease conditions has been largely ignored. To explore whether peripheral venous blood miRNAs could represent a bona fide specific miRNA deregulation pattern, we selected hypertension, a disease that is particularly associated with vessels, as the model. Circulating miRNA profiles of arterial and venous blood from spontaneously hypertensive (SHR) rats and their corresponding controls (i.e., WKY rats) were investigated by next-generation miRNA sequencing. Little miRNAs were observed between arterial and venous circulating miRNAs in WKY rats. Interestingly, this number was enhanced in SHR hypertensive rats. Bioinformatical analysis of disease association, enriched target genes and the regulatory transcription factors of these differentially expressed miRNAs implied a potential functional link with cardiovascular disease-related functions. Comparisons between arterial and venous miRNAs in hypertension-versus-control conditions also revealed prominent disease association of circulating miRNAs and their target genes in arteries but not in veins. Moreover, a young non-hypertensive animal model in SHR background (i.e. JSHR) was used as a second control for SHR. Additional transcriptomic analysis and droplet digital PCR validation of arterial and venous deregulated miRNAs among SHR and its two controls (WKY, JSHR) revealed a noticeable consensus of artery-deregulated miRNAs in hypertension and two novel arterial circulating signatures (miR-455-3p and miR-140-3p) of hypertension. These results suggest the necessity of re-evaluating the efficacy of certain venous miRNAs identified in previous studies as potential biomarkers in cardiovascular diseases or a wider disease spectrum.

Regulation of Wnt Signaling Pathways at the Plasma Membrane and Their Misregulation in Cancer

Wnt signaling is one of the key signaling pathways that govern numerous physiological activities such as growth, differentiation and migration during development and homeostasis. As pathway misregulation has been extensively linked to pathological processes including malignant tumors, a thorough understanding of pathway regulation is essential for development of effective therapeutic approaches. A prominent feature of cancer cells is that they significantly differ from healthy cells with respect to their plasma membrane composition and lipid organization. Here, we review the key role of membrane composition and lipid order in activation of Wnt signaling pathway by tightly regulating formation and interactions of the Wnt-receptor complex. We also discuss in detail how plasma membrane components, in particular the ligands, (co)receptors and extracellular or membrane-bound modulators, of Wnt pathways are affected in lung, colorectal, liver and breast cancers that have been associated with abnormal activation of Wnt signaling. Wnt-receptor complex components and their modulators are frequently misexpressed in these cancers and this appears to correlate with metastasis and cancer progression. Thus, composition and organization of the plasma membrane can be exploited to develop new anticancer drugs that are targeted in a highly specific manner to the Wnt-receptor complex, rendering a more effective therapeutic outcome possible.

Wnt signaling in breast cancer: biological mechanisms, challenges and opportunities

Wnt signaling is a highly conserved signaling pathway that plays a critical role in controlling embryonic and organ development, as well as cancer progression. Genome-wide sequencing and gene expression profile analyses have demonstrated that Wnt signaling is involved mainly in the processes of breast cancer proliferation and metastasis. The most recent studies have indicated that Wnt signaling is also crucial in breast cancer immune microenvironment regulation, stemness maintenance, therapeutic resistance, phenotype shaping, etc. Wnt/β-Catenin, Wnt-planar cell polarity (PCP), and Wnt-Ca2+ signaling are three well-established Wnt signaling pathways that share overlapping components and play different roles in breast cancer progression. In this review, we summarize the main findings concerning the relationship between Wnt signaling and breast cancer and provide an overview of existing mechanisms, challenges, and potential opportunities for advancing the therapy and diagnosis of breast cancer.

Joint reconstruction of multiple gene networks by simultaneously capturing inter-tumor and intra-tumor heterogeneity

MOTIVATION

Reconstruction of cancer gene networks from gene expression data is important for understanding the mechanisms underlying human cancer. Due to heterogeneity, the tumor tissue samples for a single cancer type can be divided into multiple distinct subtypes (inter-tumor heterogeneity) and are composed of non-cancerous and cancerous cells (intra-tumor heterogeneity). If tumor heterogeneity is ignored when inferring gene networks, the edges specific to individual cancer subtypes and cell types cannot be characterized. However, most existing network reconstruction methods do not simultaneously take inter-tumor and intra-tumor heterogeneity into account.

RESULTS

In this article, we propose a new Gaussian graphical model-based method for jointly estimating multiple cancer gene networks by simultaneously capturing inter-tumor and intra-tumor heterogeneity. Given gene expression data of heterogeneous samples for different cancer subtypes, a non-cancerous network shared across different cancer subtypes and multiple subtype-specific cancerous networks are estimated jointly. Tumor heterogeneity can be revealed by the difference in the estimated networks. The performance of our method is first evaluated using simulated data, and the results indicate that our method outperforms other state-of-the-art methods. We also apply our method to The Cancer Genome Atlas breast cancer data to reconstruct non-cancerous and subtype-specific cancerous gene networks. Hub nodes in the networks estimated by our method perform important biological functions associated with breast cancer development and subtype classification.

AVAILABILITY AND IMPLEMENTATION

The source code is available at https://github.com/Zhangxf-ccnu/NETI2.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Frizzled Receptors in Tumors, Focusing on Signaling, Roles, Modulation Mechanisms, and Targeted Therapies

Wnt molecules play crucial roles in development and adult homeostasis through their receptors Frizzled proteins (Fzds). Fzds mediate canonical β-catenin pathway and various noncanonical β-catenin-independent pathways. Aberrant Fzd signaling is involved in many diseases including cancer. Wnt/β-catenin is a well-established oncogenic pathway involved in almost every aspect of tumor development. However, Fzd-mediated noncanonical Wnt pathways function as both tumor promoters and tumor suppressors depending on cellular context. Fzd-targeted therapies have proven to be effective on cultured tumor cells, tumor cell xenografts, mouse tumor models, and patient-derived xenografts (PDX). Moreover, Fzd-targeted therapies synergize with chemotherapy in preclinical models. However, the occurrence of fragility fractures in patients treated with Fzd-targeted agents such as OMP-54F28 and OMP-18R5 limits the development of this combination. Along with new insights on signaling, roles, and modulation mechanisms of Fzds in human tumors, more Fzd-related therapeutic targets will be developed.

Glioma-initiating cells at tumor edge gain signals from tumor core cells to promote their malignancy

Intratumor spatial heterogeneity facilitates therapeutic resistance in glioblastoma (GBM). Nonetheless, understanding of GBM heterogeneity is largely limited to the surgically resectable tumor core lesion while the seeds for recurrence reside in the unresectable tumor edge. In this study, stratification of GBM to core and edge demonstrates clinically relevant surgical sequelae. We establish regionally derived models of GBM edge and core that retain their spatial identity in a cell autonomous manner. Upon xenotransplantation, edge-derived cells show a higher capacity for infiltrative growth, while core cells demonstrate core lesions with greater therapy resistance. Investigation of intercellular signaling between these two tumor populations uncovers the paracrine crosstalk from tumor core that promotes malignancy and therapy resistance of edge cells. These phenotypic alterations are initiated by HDAC1 in GBM core cells which subsequently affect edge cells by secreting the soluble form of CD109 protein. Our data reveal the role of intracellular communication between regionally different populations of GBM cells in tumor recurrence.

Intratumoural spatial heterogeneity is crucial to enhance therapeutic resistance in glioblastoma. Here, the authors show a paracrine signaling mechanism where glioblastoma-initiating cells located in the tumour edge elevate their malignancy by interaction with core-located tumour cells.

A Possible Role of FZD10 Delivering Exosomes Derived from Colon Cancers Cell Lines in Inducing Activation of Epithelial-Mesenchymal Transition in Normal Colon Epithelial Cell Line

Exosomes belong to the family of extracellular vesicles released by every type of cell both in normal and pathological conditions. Growing interest in studies indicates that extracellular vesicles, in particular, the fraction named exosomes containing lipids, proteins and nucleic acid, represent an efficient way to transfer functional cargoes between cells, thus combining all the other cell-cell interaction mechanisms known so far. Only a few decades ago, the involvement of exosomes in the carcinogenesis in different tissues was discovered, and very recently it was also observed how they carry and modulate the presence of Wnt pathway proteins, involved in the carcinogenesis of gastrointestinal tissues, such as Frizzled 10 protein (FZD10), a membrane receptor for Wnt. Here, we report the in vitro study on the capability of tumor-derived exosomes to induce neoplastic features in normal cells. Exosomes derived from two different colon cancer cell lines, namely the non-metastatic CaCo-2 and the metastatic SW620, were found to deliver, in both cases, FZD10, thus demonstrating the ability to reprogram normal colonic epithelial cell line (HCEC-1CT). Indeed, the acquisition of specific mesenchymal characteristics, such as migration capability and expression of FZD10 and markers of mesenchymal cells, was observed. The exosomes derived from the metastatic cell line, characterized by a level of FZD10 higher than the exosomes extracted from the non-metastatic cells, were also more efficient in stimulating EMT activation. The overall results suggest that FZD10, delivered by circulating tumor-derived exosomes, can play a relevant role in promoting the CRC carcinogenesis and propagation.

MiR-654-3p Suppresses Non-Small Cell Lung Cancer Tumourigenesis by Inhibiting PLK4

Purpose

MiR-654-3p plays important roles in many types of malignant tumours. However, the biological function of miR-654-3p in non-small cell lung cancer (NSCLC) remains unknown. In this study, the role of miR-654-3p in NSCLC was investigated.

Methods

qRT-PCR was used to evaluate the level of miR-654-3p in NSCLC tissues and cell lines, while Cell Counting Kit-8, Annexin V/propidium iodide dual staining or TUNEL staining were used to investigate proliferation and apoptosis of NSCLC cells. Luciferase assays and Western blotting were performed to validate potential targets of miR-654-3p.

Results

MiR-654-3p levels were significantly decreased in NSCLC patients and cell lines and were significantly correlated with the tumour size and tumour node metastasis stage of NSCLC patients. In A549 cells, miR-654-3p overexpression significantly increased apoptosis and inhibited growth both in vivo and in vitro, while downregulation of miR-654-3p had the opposite effects. In addition, polo-like kinase 4 (PLK4) was shown to be a target gene of miR-654-3p that is negatively regulated by miR-654-3p in A549 cells. Furthermore, PLK4 was observed to be highly expressed in NSCLC tissues and cells, and PLK4 overexpression abolished the inhibitory effects of miR-654-3p overexpression on NSCLC cell proliferation. Finally, the animal experiment results further demonstrated that miR-654-3p inhibits tumour growth and regulates PLK4 expression.

Conclusion

Our results demonstrate that miR-654-3p functions as a growth-suppressing miRNA by targeting PLK4 in NSCLC.

Long non-coding RNA SATB2-AS1 inhibits microRNA-155-3p to suppress breast cancer cell growth by promoting breast cancer metastasis suppressor 1-like

Background

Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) play vital roles in human cancers. Nevertheless, the effects of lncRNAs and miRNAs on breast cancer (BC) remain to be further investigated. This study was designed to testify the roles of lncRNA antisense transcript of SATB2 protein (SATB2-AS1) and microRNA-155-3p (miR-155-3p) in BC progression.

Methods

Levels of SATB2-AS1, miR-155-3p and breast cancer metastasis suppressor 1-like (BRMS1L) in BC were determined. The prognostic role of SATB2-AS1 in BC patients was assessed. The screened cells were respectively introduced with altered SATB2-AS1 or miR-155-3p to figure out their roles in malignant phenotypes of BC cells. The effect of varied SATB2-AS1 and miR-155-3p on BC cells in vivo was observed. Dual luciferase reporter gene assay and RNA-pull down assay were implemented to detect the targeting relationship of SATB2-AS1, miR-155-3p, and BRMS1L.

Results

SATB2-AS1 and BRMS1L were decreased while miR-155-3p was increased in BC cells and tissues. Patients with lower SATB2-AS1 expression had poor prognosis. Elevated SATB2-AS1 and inhibited miR-155-3p were able to restrain malignant behaviors of BC cells in vitro, as well as decelerate tumor growth in vivo. Oppositely, inhibited SATB2-AS1 and amplified miR-155-3p had converse effects on BC cell growth. MiR-155-3p mimic abrogated the impact of overexpressed SATB2-AS1. SATB2-AS1 could sponge miR-155-3p, and BRMS1L was the target gene of miR-155-3p.

Conclusion

Elevated SATB2-AS1 and inhibited miR-155-3p could suppress the malignant phenotypes of BC cells, thereby restricting the development of BC.

Yeast mismatch repair components are required for stable inheritance of gene silencing

Alterations in epigenetic silencing have been associated with ageing and tumour formation. Although substantial efforts have been made towards understanding the mechanisms of gene silencing, novel regulators in this process remain to be identified. To systematically search for components governing epigenetic silencing, we developed a genome-wide silencing screen for yeast (Saccharomyces cerevisiae) silent mating type locus HMR. Unexpectedly, the screen identified the mismatch repair (MMR) components Pms1, Mlh1, and Msh2 as being required for silencing at this locus. We further found that the identified genes were also required for proper silencing in telomeres. More intriguingly, the MMR mutants caused a redistribution of Sir2 deacetylase, from silent mating type loci and telomeres to rDNA regions. As a consequence, acetylation levels at histone positions H3K14, H3K56, and H4K16 were increased at silent mating type loci and telomeres but were decreased in rDNA regions. Moreover, knockdown of MMR components in human HEK293T cells increased subtelomeric DUX4 gene expression. Our work reveals that MMR components are required for stable inheritance of gene silencing patterns and establishes a link between the MMR machinery and the control of epigenetic silencing.

Role of cell polarity and planar cell polarity (PCP) proteins in spermatogenesis

Studies on cell polarity proteins and planar cell polarity (PCP) proteins date back to almost 40 years ago in Drosophila and C. elegans when these proteins were shown to be crucial to support apico-basal polarity and also directional alignment of polarity cells across the plane of an epithelium during morphogenesis. In adult mammals, cell polarity and PCP are most notable in cochlear hair cells. However, the role of these two groups of proteins to support spermatogenesis was not explored until a decade earlier when several proteins that confer cell polarity and PCP proteins were identified in the rat testis. Since then, there are several reports appearing in the literature to examine the role of both cell polarity and PCP in supporting spermatogenesis. Herein, we provide an overview regarding the role of cell polarity and PCP proteins in the testis, evaluating these findings in light of studies in other mammalian epithelial cells/tissues. Our goal is to provide a timely evaluation of these findings, and provide some thought provoking remarks to guide future studies based on an evolving concept in the field.

The network of non-coding RNAs and their molecular targets in breast cancer

Background

Non-coding RNAs are now recognized as fundamental components of the cellular processes. Non-coding RNAs are composed of different classes, including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Their detailed roles in breast cancer are still under scrutiny.

Main body

We systematically reviewed from recent literature the many functional and physical interactions of non-coding RNAs in breast cancer. We used a data driven approach to establish the network of direct, and indirect, interactions. Human curation was essential to de-convolute and critically assess the experimental approaches in the reviewed articles. To enrol the scientific papers in our article cohort, due to the short time span (shorter than 5 years) we considered the journal impact factor rather than the citation number.

The outcome of our work is the formal establishment of different sub-networks composed by non-coding RNAs and coding genes with validated relations in human breast cancer. This review describes in a concise and unbiased fashion the core of our current knowledge on the role of lncRNAs, miRNAs and other non-coding RNAs in breast cancer.

Conclusions

A number of coding/non-coding gene interactions have been investigated in breast cancer during recent years and their full extent is still being established. Here, we have unveiled some of the most important networks embracing those interactions, and described their involvement in cancer development and in its malignant progression.

Identification of BRMS1L as Metastasis Suppressing Gene in Esophageal Squamous Cell Carcinoma

Introduction

Breast cancer metastasis suppressor 1 like (BRMS1-like)was first reported to be a component of the Sin3-HDAC complex, but the role in the progression of cancers was largely unknown. Our previous study reported that BRMS1L promoted the metastasis of breast cancer through facilitating the recruitment of HDAC complex to the promoter FZD10, and hence suppressing the transcription of FZD10.

Methods

In this study, we detected the expression level of BRMS1L in esophageal squamous cell carcinoma (ESCC). The effect of BRMS1L in TE-1D (knockdown) and ECA-109 (overexpression) cell lines was explored by transwell assays, wound healing assays, and cell adhesion assays. Quantitative real‑time PCR, Western blot analysis, and luciferase assays were used to detect the interaction of the CBP/P300-BRMS1L-ITGA7 axis.

Results

In the present study, we found that knockdown of BRMS1L promoted the migration, invasion, and epithelial-mesenchymal transition (EMT). Conversely, overexpression of BRMS1L inhibited the migration and invasion of ESCC. Mechanistically, BRMS1L exerted their metastasis-suppressing role via transcriptionally repress ITGA7 expression. Moreover, we revealed that CBP/p 300 regulated the expression of BRMS1L and might be responsible for the down-regulation of BRMS1L in ESCC.

Conclusion

Collectively, we identified the role of CBP/p300-BRMS1L-ITGA7 axis in the metastasis of ESCC.

The characteristics of lung cancer in Xuanwei County: A review of differentially expressed genes and noncoding RNAs on cell proliferation and migration

The occurrence of lung cancers is the highest in Xuanwei County, Yunnan province, China, especially among nonsmoking women. Domestic combustion of smoky coal induces serious indoor air pollution and is considered to be the main cause of human lung cancers. The occurrence of lung cancer in Xuanwei County has unique characteristics, such as the high morbidity in nonsmoking women or people with no family history. In the present review, we summarize advances in identification of differentially expressed genes, regulatory lncRNAs and miRNAs in cell proliferation and migration of lung cancers in Xuanwei County. Moreover, several regulatory differentially expressed genes (DEGs) or noncoding RNAs have diagnostic and prognostic significance for lung cancers in Xuanwei County and have the potential to serve as biomarkers.

Downregulation of the expression of the lncRNA MIAT inhibits melanoma migration and invasion through the PI3K/AKT signaling pathway

BACKGROUND

Long noncoding RNA MIAT expression is related to the development of some diseases. However, the role of MIAT in melanoma was has seldom been studied.

OBJECTIVE

To investigate the effect of the lncRNA MIAT on melanoma cells.

METHOD

Microarray was used to analyze the lncRNAs expression in tissue samples. The expression of the lncRNA MIAT was detected by qRT-PCR. A CCK-8 assay was used to assess cell viability, and cell counting was used to analyze cell proliferation. Wound healing and Transwell invasion assays were used to detect the migration and invasion abilities, respectively, of melanoma cells. Western blotting was performed to explore the molecular mechanisms of MIAT in melanoma.

RESULTS

The lncRNA MIAT was overexpressed in melanoma. The overexpression of MIAT promoted cell proliferation, cell invasion and migration, while the knockdown of MIAT expression got the opposite results. MIAT significantly upregulated the phosphorylation of PI3K and AKT and promoted cMyc and cyclin D1 protein expression.

CONCLUSION

LncRNA MIAT was a key factor to promote cell invasion, migration and proliferation through the PI3K/AKT signaling pathway. These findings may give us a potential way to treat melanoma.

RNA Sequencing Reveals the Activation of Wnt Signaling in Low Flow Rate Brain Arteriovenous Malformations

Background

The blood flow rate of brain arteriovenous malformations (bAVMs) is an important clinical characteristic closely associated with the hemorrhage risk and radiosurgery obliteration rate of bAVMs. However, the underlying molecular properties remain unclear. To identify potential key molecules, signaling pathways, and vascular cell types involved, we compared gene expression profiles between bAVMs with high flow rates and low flow rates (LFR) and validated the functions of selected key molecules in vitro.

Methods and Results

We performed RNA‐sequencing analysis on 51 samples, including 14 high flow rate bAVMs and 37 LFR bAVMs. Functional pathway analysis was performed to identify potential signals influencing the flow rate phenotype of bAVMs. Candidate genes were investigated in bAVM specimens by immunohistochemical staining. Migration, tube formation, and proliferation assays were used to test the effects of candidate genes on the phenotypic properties of cultured human umbilical vein endothelial cells and human brain vascular smooth muscle cells. We identified 250 upregulated and 118 downregulated genes in LFR bAVMs compared with high flow rate bAVMs. Wnt signaling was activated in the LFR group via upregulation of FZD10 and MYOC. Immunohistochemical staining showed that vascular endothelial and smooth muscle cells of LFR bAVMs exhibited increased FZD10 and MYOC expression. Experimentally elevating these genes promoted human umbilical vein endothelial cells and migration and tube formation by activating canonical Wnt signaling in vitro.

Conclusions

Our results suggest that canonical Wnt signaling mediated by FZD10 and MYOC is activated in vascular endothelial and smooth muscle cells in LFR bAVMs.

Higher order genomic organization and epigenetic control maintain cellular identity and prevent breast cancer

Cells establish and sustain structural and functional integrity of the genome to support cellular identity and prevent malignant transformation. In this review, we present a strategic overview of epigenetic regulatory mechanisms including histone modifications and higher order chromatin organization (HCO) that are perturbed in breast cancer onset and progression. Implications for dysfunctions that occur in hormone regulation, cell cycle control, and mitotic bookmarking in breast cancer are considered, with an emphasis on epithelial-to-mesenchymal transition and cancer stem cell activities. The architectural organization of regulatory machinery is addressed within the contexts of translating cancer-compromised genomic organization to advances in breast cancer risk assessment, diagnosis, prognosis, and identification of novel therapeutic targets with high specificity and minimal off target effects.

Epigenetics in Metastatic Breast Cancer: Its Regulation and Implications in Diagnosis, Prognosis and Therapeutics

Despite advances in the treatment regimen, the high incidence rate of breast cancer (BC) deaths is mostly caused by metastasis. Recently, the aberrant epigenetic modifications, which involve DNA methylation, histone modifications and microRNA (miRNA) regulations become attractive targets to treat metastatic breast cancer (MBC). In this review, the epigenetic alterations of DNA methylation, histone modifications and miRNA regulations in regulating MBC are discussed. The preclinical and clinical trials of epigenetic drugs such as the inhibitor of DNA methyltransferase (DNMTi) and the inhibitor of histone deacetylase (HDACi), as a single or combined regimen with other epigenetic drug or standard chemotherapy drug to treat MBCs are discussed. The combined regimen of epigenetic drugs or with standard chemotherapy drugs enhance the therapeutic effect against MBC. Evidences that epigenetic changes could have implications in diagnosis, prognosis and therapeutics for MBC are also presented. Several genes have been identified as potential epigenetic biomarkers for diagnosis and prognosis, as well as therapeutic targets for MBC. Endeavors in clinical trials of epigenetic drugs against MBC should be continued although limited success has been achieved. Future discovery of epigenetic drugs from natural resources would be an attractive natural treatment regimen for MBC. Further research is warranted in translating research into clinical practice with the ultimate goal of treating MBC by epigenetic therapy in the near future.

Cis-Acting circ-CTNNB1 Promotes β-Catenin Signaling and Cancer Progression via DDX3-Mediated Transactivation of YY1

Circular RNAs (circRNA), a subclass of noncoding RNA characterized by covalently closed continuous loops, play emerging roles in tumorigenesis and aggressiveness. However, the functions and underlying mechanisms of circRNA in regulating Wnt/β-catenin signaling and cancer progression remain elusive. Here, we screen cis-acting circRNA generated by β-catenin (CTNNB1)/transcription factor 7-like 2 genes and identify one intronic circRNA derived from CTNNB1 (circ-CTNNB1) as a novel driver of cancer progression. Circ-CTNNB1 was predominantly expressed in the nucleus, upregulated in cancer tissues and cell lines, and associated with unfavorable outcomes in patients with cancer. Circ-CTNNB1 promoted β-catenin activation, growth, invasion, and metastasis in cancer cells. Circ-CTNNB1 bound DEAD-box polypeptide 3 (DDX3) to facilitate its physical interaction with transcription factor Yin Yang 1 (YY1), resulting in the transactivation of YY1 and transcriptional alteration of downstream genes associated with β-catenin activation and cancer progression. Preclinically, administration of lentivirus-mediated short hairpin RNA targeting circ-CTNNB1 or a cell-penetrating inhibitory peptide blocking the circ-CTNNB1-DDX3 interaction inhibited downstream gene expression, tumorigenesis, and aggressiveness in cancer cells. Taken together, these results demonstrate cis-acting circ-CTNNB1 as a mediator of β-catenin signaling and cancer progression through DDX3-mediated transactivation of YY1. SIGNIFICANCE: These findings reveal the oncogenic functions of a cis-acting circular RNA in β-catenin activation and cancer progression, with potential value as a therapeutic target for human cancers.

Decreased BRMS1L expression is correlated with glioma grade and predicts poor survival in glioblastoma via an invasive phenotype

AIMS

To evaluate the prognostic and clinicopathological features of glioma with BRMS1L expression.

METHODS

Total 120 glioma samples were obtained as discovery cohort. CGGA, GSE and TCGA datasets were obtained as validation sets. Furthermore, Kaplan-Meier survival and multivariate Cox analysis were used to evaluate the survival distributions. Moreover, the functional role of BRMS1L was also analyzed by transwell assay.

RESULTS

In the discovery cohort, decreased BRMS1L expression was significantly associated with high-grade glioma as well as the higher mortality in survival analysis (log-rank test, p< 0.01). And the three validation cohorts showed the similar results. Furthermore, BRMS1L act as an independent prognostic factor in glioblastoma patients. Additionally, functional assay showed that ectopic of BRMS1L suppressed glioma cells' invasion.

CONCLUSION

BRMS1L plays as an anti-oncogene in GBM and indicates a new potential therapeutic target.

Targeted imaging and inhibition of triple-negative breast cancer metastases by a PDGFRβ aptamer

While the overall mortality for breast cancer has recently declined, management of triple-negative breast cancer (TNBC) is still challenging because of its aggressive clinical behavior and the lack of targeted therapies. Genomic profiling studies highlighted the high level of heterogeneity of this cancer, which comprises different subtypes with unique phenotypes and response to treatment. Platelet-derived growth factor receptor β (PDGFRβ) is an established mesenchymal/stem cell-specific marker in human glioblastoma and, as recently suggested, it may uniquely mark breast cancer cells with stem-like characteristics and/or that have undergone epithelial-mesenchymal transition.

Methods: Immunohistochemical analysis for PDGFRβ expression was performed on a human TNBC tissue microarray. Functional assays were conducted on mesenchymal-like TNBC cells to investigate the effect of a previously validated PDGFRβ aptamer on invasive cell growth in three-dimensional culture conditions, migration, invasion and tube formation. The aptamer was labeled with a near-infrared (NIR) dye and its binding specificity to PDGFRβ was assessed both in vitro (confocal microscopy and flow cytometry analyses) and in vivo (fluorescence molecular tomography in mice bearing TNBC xenografts). A mouse model of TNBC lung metastases formation was established and NIR-labeled PDGFRβ aptamer was used to detect lung metastases in mice untreated or intravenously injected with unlabeled aptamer.

Results: Here, we present novel data showing that tumor cell expression of PDGFRβ identifies a subgroup of mesenchymal tumors with invasive and stem-like phenotype, and propose a previously unappreciated role for PDGFRβ in driving TNBC cell invasiveness and metastases formation. We show that the PDGFRβ aptamer blocked invasive growth and migration/invasion of mesenchymal TNBC cell lines and prevented TNBC lung metastases formation. Further, upon NIR-labeling, the aptamer specifically bound to TNBC xenografts and detected lung metastases.

Conclusions: We propose PDGFRβ as a reliable biomarker of a subgroup of mesenchymal TNBCs with invasive and stem-like phenotype as well as the use of the PDGFRβ aptamer as a high efficacious tool for imaging and suppression of TNBC lung metastases. This study will allow for the significant expansion of the current repertoire of strategies for managing patients with more aggressive TNBC.

Integrated analysis of DNA methylation profiling and gene expression profiling identifies novel markers in lung cancer in Xuanwei, China

BACKGROUND

Aberrant DNA methylation occurs frequently in cancer. The aim of this study was to identify novel methylation markers in lung cancer in Xuanwei, China, through integrated genome-wide DNA methylation and gene expression studies.

METHODS

Differentially methylated regions (DMRs) and differentially expressed genes (DEGs) were detected on 10 paired lung cancer tissues and noncancerous lung tissues by methylated DNA immunoprecipitation combined with microarray (MeDIP-chip) and gene expression microarray analyses, respectively. Integrated analysis of DMRs and DEGs was performed to screen out candidate methylation-related genes. Both methylation and expression changes of the candidate genes were further validated and analyzed.

RESULTS

Compared with normal lung tissues, lung cancer tissues expressed a total of 6,899 DMRs, including 5,788 hypermethylated regions and 1,111 hypomethylated regions. Integrated analysis of DMRs and DEGs identified 45 tumor-specific candidate genes: 38 genes whose DMRs were hypermethylated and expression was downregulated, and 7 genes whose DMRs were hypomethylated and expression was upregulated. The methylation and expression validation results identified 4 candidate genes (STXBP6, BCL6B, FZD10, and HSPB6) that were significantly hypermethylated and downregulated in most of the tumor tissues compared with the noncancerous lung tissues.

CONCLUSIONS

This integrated analysis of genome-wide DNA methylation and gene expression in lung cancer in Xuanwei revealed several genes regulated by promoter methylation that have not been described in lung cancer before. These results provide new insight into the carcinogenesis of lung cancer in Xuanwei and represent promising new diagnostic and therapeutic targets.

Wnt signaling in human and mouse breast cancer: Focusing on Wnt ligands, receptors and antagonists

Wnt proteins, a group of secreted glycoproteins, mainly combine with receptors Frizzled (FZD) and/or low-density-lipoprotein receptor-related proteins 5/6 (LRP5/6), initiating β-catenin-dependent and -independent signaling pathways. These pathways, which can be regulated by some secreted antagonists such as secreted Frizzled-related proteins (SFRP) and dickkopf-related protein (DKK), play a critical role in embryo development and adult homeostasis. Overactivation of Wnt signaling has been implicated in some human diseases including cancer. Wnt transgenic mice provide convincing evidence that Wnt signaling is involved in breast cancer initiation and progression, which is further strengthened by observations on human clinical breast cancer patients and studies on in vitro cultured human breast cancer cells. This review focuses on the roles of Wnt ligands, receptors and antagonists in breast cancer development instead of molecules or signaling transactivating β-catenin independent on Wnt upstream components.