DKK1 inhibits breast cancer cell migration and invasion through suppression of β-catenin/MMP7 signaling pathway

Dickopff 1 inhibits cancer stem cell properties and promotes neuronal differentiation of human neuroblastoma cell line SH-SY5Y

Neuroblastomas are pediatric tumors arising from undifferentiated cells of neural crest origin with stem cell-like characteristics. Dysregulation of Wnt/β-catenin signaling has been shown to be linked to the development of various tumors. Activated Wnt signaling results in β-catenin accumulation in the nucleus to support pro-neoplastic traits. DKK1, a secreted glycoprotein, is an inhibitor of Wnt signaling, and the addition of DKKI to the culture medium has been used to suppress the Wnt pathway. This study aimed to analyze the role of Dickopff-1 as a potential differentiating agent for the neuroblastoma cell line SH-SY5Y and neurospheres derived from it. The treatment of SH-5Y5Y derived neurospheres by DKK1 resulted in their disintegration and reduced proliferation markers like Ki67, PCNA. DKK1 treatment to the neurospheres also resulted in the loss of cancer stem cell markers like CD133, KIT and pluripotency markers like SOX2, OCT4, NANOG. DKK1 treatment caused reduction in mRNA expression of β-catenin and TCF genes like TCF4, TCF12. When the SH-SY5Y cancer cells were grown under differentiating conditions, DKKI caused neuronal differentiation by itself, and in synergy with retinoic acid. This was verified by the expression of markers like MAPT, DCX, GAP43, ENO2 and also with changes in neurite length. We concluded that Wnt inhibition, as exemplified by DKK1 treatment, is therefore a possible differentiating condition and also suppresses the proliferative and cancer stemness related properties of SH-SY5Y neuroblastoma cells.

RNF4 mediated degradation of PDHA1 promotes colorectal cancer metabolism and metastasis

This study investigates the role of RNF4-mediated ubiquitination and degradation of PDHA1 in colorectal cancer (CRC) metabolism and metastasis. Integrating (The Cancer Genome Atlas) TCGA and Clinical Proteomic Tumor Analysis Consortium (CPTAC) databases, proteomic, clinical, and metabolomic analyses were performed, revealing PDHA1 as a prognostic marker in CRC. Immunohistochemical staining confirmed lower PDHA1 expression in metastatic CRC tissues. In vitro experiments demonstrated that PDHA1 overexpression inhibited CRC cell proliferation, migration, and invasion. RNF4 was identified as a key mediator in the ubiquitination degradation of PDHA1, influencing glycolytic pathways in CRC cells. Metabolomic analysis of serum samples from metastatic CRC patients further supported these findings. In vivo experiments, including xenograft and metastasis models, validated that RNF4 knockdown stabilized PDHA1, inhibiting tumor formation and metastasis. This study highlights the critical role of RNF4-mediated PDHA1 ubiquitination in promoting glycolytic metabolism, proliferation, and metastasis in CRC.

Reprogramming of normal fibroblasts into ovarian cancer-associated fibroblasts via non-vesicular paracrine signaling induces an activated fibroblast phenotype

Cancer-associated fibroblasts (CAFs) are key contributors to ovarian cancer (OC) progression and therapeutic resistance through dysregulation of the extracellular matrix (ECM). CAFs are a heterogenous population derived from different cell types through activation and reprogramming. Current studies rely on uncharacterized heterogenous primary CAFs or normal fibroblasts that fail to recapitulate CAF-like tumor behavior. Here, we present that conditioned media from ovarian cancer lines leads to an increase in the activated state of fibroblasts demonstrated by functional assays and up-regulation of known CAF-related genes and ECM pathways. Phenotypic and functional characterization demonstrated that the conditioned CAFs expressed a CAF-like phenotype, strengthened proliferation, secretory, contractility, and ECM remodeling properties when compared to resting normal fibroblasts, consistent with an activated fibroblast status. Moreover, conditioned CAFs significantly enhanced drug resistance and tumor progression. Critically, the conditioned CAFs resemble a transcriptional signature with involvement of ECM remodeling. The present study provides mechanistic and functional insights about the activation and reprogramming of CAFs in the ovarian tumor microenvironment mediated by non-vesicular paracrine signaling. Moreover, it provides a translational based approach to reprogram normal fibroblasts from both uterine and ovarian origin into CAFs using tumor-derived conditioned media. Using these resources, further development of therapeutics that possess potentiality and specificity towards CAF/ECM-mediated chemoresistance in OC are further warranted.

Dexamethasone-tamoxifen combination exerts synergistic therapeutic effects in tamoxifen-resistance breast cancer cells

Tamoxifen (TAM) is a key player in estrogen receptor-positive (ER+) breast cancer (BC); however, ∼30% of patients experience relapse and a lower survival rate due to TAM resistance. TAM resistance was related to the over expression of SOX-2 gene, which is regulated by the E2F3 transcription factor in the Wnt signaling pathway. It was suggested that SOX-2 overexpression was suppressed by dexamethasone (DEX), a glucocorticoid commonly prescribed to BC patients. The aim of the present study is to explore the effect of combining DEX and TAM on the inhibition of TAM-resistant LCC-2 cells (TAMR-1) through modulating the E2F3/SOX-2-mediated Wnt signaling pathway. The effect of the combination therapy on MCF-7 and TAMR-1 cell viability was assessed. Drug interactions were analyzed using CompuSyn and SynergyFinder softwares. Cell cycle distribution, apoptotic protein expression, gene expression levels of SOX-2 and E2F3, and cell migration were also assessed. Combining DEX with TAM led to synergistic inhibition of TAMR-1 cell proliferation and migration, induced apoptosis, reduced SOX-2 and E2F3 expression and was also associated with S and G2-M phase arrest. Therefore, combining DEX with TAM may present an effective therapeutic option to overcome TAM resistance, by targeting the E2F3/SOX-2/Wnt signaling pathway, in addition to its anti-inflammatory effect.

Knockdown of ADAM8 inhibits the proliferation, migration, invasion, and tumorigenesis of renal clear cell carcinoma cells to enhance the immunotherapy efficacy

The current study performed bioinformatics and in vitro and in vivo experiments to explore the effects of ADAM8 on the malignant behaviors and immunotherapeutic efficacy of renal clear cell carcinoma (ccRCC) Cells. The modular genes most associated with immune cells were screened. Then, prognostic risk models were constructed by univariate COX analysis, LASSO regression analysis and multivariate COX analysis, and their diagnostic value was determined. The correlation between tumor mutation load (TMB) scores and the prognosis of ccRCC patients was clarified. Finally, six key genes (ABI3, ADAM8, APOL3, MX2, CCDC69, and STAC3) were analyzed for immunotherapy efficacy. Human and mouse ccRCC cell lines and human proximal tubular epithelial cell lines were used for in vitro cell experiments. The effect of ADAM8 overexpression or knockdown on tumor formation and survival in ccRCC cells was examined by constructing subcutaneous transplanted tumor model. Totally, 636 Black module genes were screened as being most associated with immune cell infiltration. Six genes were subsequently confirmed for the construction of prognostic risk models, of which ABI3, APOL3 and CCDC69 were low-risk factors, while ADAM8, MX2 and STAC3 were high-risk factors. The constructed risk model based on the identified six genes could accurately predict the prognosis of ccRCC patients. Besides, TMB was significantly associated with the prognosis of ccRCC patients. Furthermore, ABI3, ADAM8, APOL3, MX2, CCDC69 and STAC3 might play important roles in treatment concerning CTLA4 inhibitors or PD-1 inhibitors or combined inhibitors. Finally, we confirmed that ADAM8 could promote the proliferation, migration and invasion of ccRCC cells through in vitro experiments, and further found that in in vivo experiments, ADAM8 knockdown could inhibit tumor formation in ccRCC cells, improve the therapeutic effect of anti-PD1, and prolong the survival of mice. Our study highlighted the alleviative role of silencing ADAM8 in ccRCC patients.

Cellular and Exosomal MicroRNAs: Emerging Clinical Relevance as Targets for Breast Cancer Diagnosis and Prognosis

Breast cancer accounts for the highest cancer cases globally, with 12% of occurrences progressing to metastatic breast cancer with a low survival rate and limited effective early intervention strategies augmented by late diagnosis. Moreover, a low concentration of prognostic and predictive markers hinders disease monitoring. Circulating and exosomal microRNAs (miRNAs) have recently shown a considerable interplay in breast cancer, standing out as effective diagnostic and prognostic markers. The primary functions are as gene regulatory agents at the genetic and epigenetic levels. An array of dysregulated miRNAs stimulates cancer-promoting mechanisms, activating oncogenes and controlling tumor-suppressing genes and mechanisms. Exosomes are vastly studied extracellular vesicles, carrying, and transporting cargo, including noncoding RNAs with premier roles in oncogenesis. Translocation of miRNAs from the circulation to exosomes, with RNA-binding proteins in stress-induced conditions, has shown significant cooperation in function to promote breast cancer. This review examines cellular and exosomal miRNA biogenesis and loading, the clinical implications of their dysregulation, their function in diagnosis, prognosis, and prediction of breast cancer, and in regulating cancer signaling pathways. The influence of cellular and exosomal miRNAs presents clinical significance on breast cancer diagnosis, subtyping, staging, prediction, and disease monitoring during treatment, hence a potent marker for breast cancer.

Role of prognostic gene DKK1 in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common squamous cell carcinomas of the head and neck. The morbidity and mortality rates of OSCC have increased in recent years. However, the pathogenesis of this disease remains unknown. The present study aimed to identify predictive biomarkers and therapeutic targets for OSCC. Bioinformatics screening of differentially expressed genes in OSCC was performed based on data from The Cancer Genome Atlas and Gene Expression Omnibus databases. Dickkopf Wnt signaling pathway inhibitor 1 (DKK1) was identified to be associated with survival, tumor immunity and DNA repair in OSCC. Furthermore, the effects of DKK1 were evaluated by the knockdown of DKK1 in two OSCC cell lines. The proliferation, clonogenicity, migration and invasion of the cells were assessed in vitro using Cell Counting Kit-8, colony formation, wound healing and Transwell assays, respectively, and were found to be inhibited by DKK1 knockdown. The present study suggests that DKK1 may be used in the prognosis of patients with OSCC and that targeting DKK1 is a potential strategy for OSCC therapy.

Unravelling transcriptomic complexity in breast cancer through modulation of DARPP-32 expression and signalling pathways

DARPP-32 is a key regulator of protein-phosphatase-1 (PP-1) and protein kinase A (PKA), with its function dependent upon its phosphorylation state. We previously identified DKK1 and GRB7 as genes with linked expression using Artificial Neural Network (ANN) analysis; here, we determine protein expression in a large cohort of early-stage breast cancer patients. Low levels of DARPP-32 Threonine-34 phosphorylation and DKK1 expression were significantly associated with poor patient prognosis, while low levels of GRB7 expression were linked to better survival outcomes. To gain insight into mechanisms underlying these associations, we analysed the transcriptome of T47D breast cancer cells following DARPP-32 knockdown. We identified 202 differentially expressed transcripts and observed that some overlapped with genes implicated in the ANN analysis, including PTK7, TRAF5, and KLK6, amongst others. Furthermore, we found that treatment of DARPP-32 knockdown cells with 17β-estradiol or PKA inhibitor fragment (6-22) amide led to the differential expression of 193 and 181 transcripts respectively. These results underscore the importance of DARPP-32, a central molecular switch, and its downstream targets, DKK1 and GRB7 in breast cancer. The discovery of common genes identified by a combined patient/cell line transcriptomic approach provides insights into the molecular mechanisms underlying differential breast cancer prognosis and highlights potential targets for therapeutic intervention.

Mitochondrial-related genes markers that predict survival in patients with head and neck squamous cell carcinoma affect immunomodulation through hypoxia, glycolysis, and angiogenesis pathways

Mitochondria play a crucial role in the occurrence and development of tumors. We used mitochondria-related genes for consistent clustering to identify three stable molecular subtypes of head and neck squamous cell carcinoma (HNSCC) with different prognoses, mutations, and immune characteristics. Significant differences were observed in clinical characteristics, immune microenvironment, immune cell infiltration, and immune cell scores. TP53 was the most significantly mutated; cell cycle-related pathways and tumorigenesis-related pathways were activated in different subtypes. Risk modeling was conducted using a multifactor stepwise regression method, and nine genes were identified as mitochondria-related genes affecting prognosis (DKK1, EFNB2, ITGA5, AREG, EPHX3, CHGB, P4HA1, CCND1, and JCHAIN). Risk score calculations revealed significant differences in prognosis, immune cell scores, immune cell infiltration, and responses to conventional chemotherapy drugs. Glycolysis, angiogenesis, hypoxia, and tumor-related pathways were positively correlated with the RiskScore. Clinical samples were subjected to qPCR to validate the results. In this work, we constructed a prognostic model based on the mitochondrial correlation score, which well reflects the risk and positive factors for the prognosis of patients with HNSCC. This model can be used to guide individualized adjuvant and immunotherapy in patients with HNSCC.

Prediction of prognosis and immunotherapy response in lung adenocarcinoma based on CD79A, DKK1 and VEGFC

Background

Tumor immune microenvironment (TIME) is crucial for tumor initiation, progression, and metastasis; however, its relationship with lung adenocarcinoma (LUAD) is unknown. Traditional predictive models screen for biomarkers that are too general and infrequently associated with immune genes.

Methods

RNA sequencing data of LUAD patients and immune-related gene sets were retrieved from public databases. Using the common genes shared by The Cancer Genome Atlas (TCGA) and Immunology Database and Analysis Portal (ImmPort), differential gene expression analysis, survival analysis, Lasso regression analysis, and univariate and multivariate Cox regression analyses were performed to generate a novel risk score model. LUAD cohort in International Cancer Genome Consortium (ICGC), GSE68465 cohort in Gene Expression Omnibus (GEO) and an immunohistochemical assay were used to validate the key genes constructed risk score. The LUAD-related prognosis, clinical indicators, immune infiltrate characteristics, response to immunotherapy, and response to chemotherapeutic agents in different risk groups were evaluated by CIBERSORT, ImmuCellAI, pRRophetic and other tools.

Results

The risk score model was constructed using CD79a molecule (CD79A), Dickkopf WNT signaling pathway inhibitor 1 (DKK1), and vascular endothelial growth factor C (VEGFC). High risk score was identified as a negative predictor for overall survival (OS) in subgroup analyses with tumor stage, TNM classification, therapy outcome, and ESTIMATE scores (P < 0.05). Low risk score was positively associated with plasma cells, memory B cells, CD8 T cells, regulatory T cells and γδT cells (P < 0.05). In low-risk group, programmed cell death 1 receptor (PD1), cytotoxic T-lymphocyte associated protein 4 (CTLA4), and lymphocyte activating 3 (LAG3) and indoleamine 2,3-dioxygenase (IDO) were more robustly expressed (P < 0.05). The treatment responses of immune checkpoint blockade (ICB) therapy and chemotherapy were likewise superior in low-risk group (P < 0.05). In immunohistochemical analysis, the tumor group had significantly higher levels of CD79A, DKK1, and VEGFC than the adjacent normal group (P < 0.01).

Conclusions

CD79A, DKK1 and VEGFC are important differential genes related to LUAD, risk score could reliably predict prognosis, composition of TIME and immunotherapy responses in LUAD patients. The excellent performance of the risk model shows its strong and broad application potential.

RAGE inhibitor TTP488 (Azeliragon) suppresses metastasis in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a highly aggressive and metastatic cancer subtype, which is generally untreatable once it metastasizes. We hypothesized that interfering with the Receptor for Advanced Glycation End-products (RAGE) signaling with the small molecule RAGE inhibitors (TTP488/Azeliragon and FPS-ZM1) would impair TNBC metastasis and impair fundamental mechanisms underlying tumor progression and metastasis. Both TTP488 and FPS-ZM1 impaired spontaneous and experimental metastasis of TNBC models, with TTP488 reducing metastasis to a greater degree than FPS-ZM1. Transcriptomic analysis of primary xenograft tumor and metastatic tissue revealed high concordance in gene and protein changes with both drugs, with TTP488 showing greater potency against metastatic driver pathways. Phenotypic validation of transcriptomic analysis by functional cell assays revealed that RAGE inhibition impaired TNBC cell adhesion to multiple extracellular matrix proteins (including collagens, laminins, and fibronectin), migration, and invasion. Neither RAGE inhibitor impaired cellular viability, proliferation, or cell cycle in vitro. Proteomic analysis of serum from tumor-bearing mice revealed RAGE inhibition affected metastatic driver mechanisms, including multiple cytokines and growth factors. Further mechanistic studies by phospho-proteomic analysis of tumors revealed RAGE inhibition led to decreased signaling through critical BC metastatic driver mechanisms, including Pyk2, STAT3, and Akt. These results show that TTP488 impairs metastasis of TNBC and further clarifies the signaling and cellular mechanisms through which RAGE mediates metastasis. Importantly, as TTP488 displays a favorable safety profile in human studies, our study provides the rationale for evaluating TTP488 in clinical trials to treat or prevent metastatic TNBC.

Seven Immune-Related Genes' Prognostic Value and Correlation with Treatment Outcome in Head and Neck Squamous Cell Carcinoma

Background

Head and neck squamous cell carcinoma (HNSCC) is a growing concern worldwide, due to its poor prognosis, low responsiveness to treatment, and drug resistance. Since immunotherapy effectively improves HNSCC patients' survival status, it is important to continuously explore new immune-related predictive factors to accurately predict the immune landscape and clinical outcomes of individuals suffering from HNSCC.

Methods

The HNSCC transcriptome profiling of RNA-sequencing data was retrieved from TCGA database, and the microarray of GSE27020 was obtained from the GEO database for validation. The differentially expressed genes (DEGs) between HNSCC and normal samples were identified by multiple test corrections in TCGA database. The univariate and multivariate Cox analyses were performed to identify proper immune-related genes (IRGs) to construct a risk model. The Cox regression coefficient was employed for calculation of the risk score (RS) of IRG signature. The median value of RS was utilized as a basis to classify individuals with HNSCC into high- and low-risk groups. The Kaplan-Meier (K-M) survival analysis and receiver operating characteristic (ROC) curves were employed for the identification of the prognostic significance and precision of the IRG signature. The signature was also evaluated based on clinical variables, predictive nomogram, mutation analysis, infiltrating immune cells, immune-related pathways, and chemotherapeutic efficacy. The protein-protein interaction (PPI) network and functional enrichment pathway investigations were utilized to explore possible potential molecular mechanisms. Finally, the hub gene's differential mRNA expression levels were evaluated by means of the Gene Expression Profiling Interactive Analysis (GEPIA), and the Human Protein Atlas (HPA) was utilized for the validation of their translational levels.

Results

Collectively, 1593 DEGs between HNSCC and normal samples were identified, of which 136 IRGs were differentially expressed. Then, the 136 immune-related DEGs were mostly enriched in the cytokine-related signaling pathways by GO and KEGG analyses. After that, a valuable signature based on seven genes (DKK1, GAST, IGHM, IL12RB2, SLURP1, STC2, and TNFRSF4) was designed. The HNSCC patients into the low-risk group and the high-risk group were divided by using the median RS; the HNSCC patients in the high-risk group had a worse survival than those in the low-risk group. The risk signature was verified to be an independent predictive marker for HNSCC patients. Meanwhile, the RS had the largest contribution to survival of these patients based on the predictive nomogram. In addition, the low-risk HNSCC patients exhibited significantly enriched immune cells, along with an association with high chemosensitivity.

Conclusion

The constructed gene signature can independently function as a predictive indicator for the clinical features of HNSCC patients. The low-risk HNSCC subjects might benefit from immunotherapy and chemotherapy.

Atrazine promotes breast cancer development by suppressing immune function and upregulating MMP expression

There is evidence that the triazine herbicide atrazine, which is used extensively, is present in both surface water and groundwater, and its interfering effect on immune systems, endocrine systems, and tumours has been reported by laboratory and epidemiological studies. This study explored how atrazine affected 4T1 breast cancer cell development in vitro and in vivo. The obtained results showed that after exposure to atrazine, the cell proliferation and tumour volume were significantly increased and the expression of MMP2, MMP7, and MMP9 was upregulated. The thymus and spleen indices, the CD4 + and CD3 + lymphocyte percentages which from the spleen and inguinal lymph nodes, and the CD4 + /CD8 + ratio were noticeably lower than they were in the control group. Importantly, tumour-infiltrating lymphocytes such as CD4 + , CD8 + , and NK cells were decreased while Treg cells were increased. Moreover, IL-4 was increased and IFN-γ and TNF-α were decreased in the serum and tumour microenvironment. These results suggested that atrazine can suppress systemic as well as local tumour immune function and upregulate MMPs to promote breast tumour development.

Long non-coding RNA telomerase RNA elements improve glucocorticoid-induced osteoporosis by EZH2 to regulate DKK1

BACKGROUND

Glucocorticoid-induced osteoporosis is the most common secondary cause of osteoporosis, which increases the risk of fracture. Long non-coding RNA telomerase RNA elements (TERC) has been proven to be closely related to osteoporosis. However, the role of TERC in glucocorticoid-induced osteoporosis and its underlying molecular mechanism remains unclear.

METHODS

The in vitro model of osteoporosis was established after bone marrow mesenchymal stem cells (BMSCs) were exposed to dexamethasone (DEX). The cell viability, alkaline phosphatase (ALP) activity and mineralized nodules of BMSCs were evaluated. The messenger RNA and protein levels were detected by quantitative real-time polymerase chain reaction and Western blot. The interaction between TERC, enhancer of zeste homolog 2 (EZH2) and dickkopf-1 (DKK1) was confirmed by chromatin immunoprecipitation and RNA immunoprecipitation assays.

RESULTS

Bone marrow mesenchymal stem cells were isolated, identified and induced osteogenic differentiation. The findings showed that the levels of osteogenic marker genes, including ALP, Runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN) in BMSCs were increased dependent on the osteogenic induction time. Similarly, TERC was significantly increased, but DKK1 was significantly decreased during BMSC osteogenic differentiation. Functional research showed that TERC overexpression promoted cell viability, ALP activity and mineralized nodules of BMSCs and increased the levels of osteogenic differentiation-related genes (ALP, RUNX2 and OCN), and TERC overexpression increased EZH2 protein level. Moreover, the decrease of cell viability, ALP activity and mineralized nodules induced by DEX was reversed by TERC overexpression. Furthermore, TERC inhibited DKK1 expression by promoting the histone modification of DKK1, and TERC overexpression alleviated DEX suppressed osteogenic differentiation of BMSCs by interaction with EZH2 to regulate DKK1.

CONCLUSION

Our findings illustrated that TERC overexpression alleviated DEX-induced osteoporosis by recruiting EZH2 to regulate DKK1. Our research provided a novel direction for the treatment of glucocorticoid-induced osteoporosis.

Dickkopf-1 drives tumor immune evasion by inducing PD-L1 expression in hepatocellular carcinoma

Understanding the mechanisms regulating PD-L1 expression in hepatocellular carcinoma (HCC) is important to improve the response rate to PD-1/PD-L1 blockade therapy. Here, we show that DKK1 expression is positively associated with PD-L1 expression and inversely correlated with CD8⁺ T cell infiltration in human HCC tumor specimens. In a subcutaneous xenograft tumor model, overexpression of DKK1 significantly promotes tumor growth, tumoral PD-L1 expression, but reduces tumoral CD8⁺ T cell infiltration; whereas knockdown of DKK1 has opposite effects. Moreover, enforced expression of DKK1 dramatically promotes PD-L1 expression, Akt activation, β-catenin phosphorylation and total protein expression in HCC cells. By contrast, knockdown of DKK1 inhibits all, relative to controls. In addition, CKAP4 depletion, Akt inhibition, or β-catenin depletion remarkably abrogates DKK1 overexpression-induced transcriptional expression of PD-L1 in HCC cells. Reconstituted expression of the active Akt1 largely increased PD-L1 transcriptional expression in HCC cells. Similarly, expression of WT β-catenin, but not the phosphorylation-defective β-catenin S552A mutant, significantly promotes PD-L1 expression. Correlation analysis of human HCC tumor specimens further revealed that DKK1 and PD-L1 expression were positively correlated with p-β-catenin expression. Together, our findings revealed that DKK1 promotes PD-L1 expression through the activation of Akt/β-catenin signaling, providing a potential strategy to enhance the clinical efficacy of PD-1/PD-L1 blockade therapy in HCC patients.

Correlation of NNMT and DKK1 Protein Expression With Clinicopathological Characteristics and Prognosis of Breast Cancer

Background

Nicotinamide N-methyltransferase (NNMT) and Dickkopf-1 (DKK1) play an important role in the development of breast cancer, and the purpose of this study was designed to examine the clinical and prognostic significance of NNMT and DKK1 in breast cancer.

Methods

The GEPIA2 database was used to evaluate the expression and survival of NNMT mRNA and DKK1 mRNA of breast cancer. Then an immunohistochemical study was carried out on 374 cases of breast tissue to identify the protein expression and significance of NNMT and DKK1. Next, the prognostic significance of DKK1 in breast cancer was explored by COX and Kaplan-Meier models.

Results

Protein NNMT expression was correlated with lymph node metastasis and histological grade (P < .05) while protein DKK1 expression was related to tumor size, pT stage, histological grade, and Ki-67 (P < .05). Protein DKK1 was related to disease-specific survival (DSS), and low DKK1 expression indicated a poor prognosis of breast cancer patients (P < .05). Combined expression of protein NNMT and protein DKK1 predicted different prognosis of DSS (P < .05).

Conclusions

Nicotinamide N-methyltransferase and DKK1 were linked to breast cancer malignancy and invasion. Breast cancer patients with low DKK1 expression had a worse prognosis. Oncotypes of NNMT and DKK1 expression predicted patient outcomes.

Identification of immune biomarkers associated with basement membranes in idiopathic pulmonary fibrosis and their pan-cancer analysis

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease of unknown etiology, characterized by diffuse alveolitis and alveolar structural damage. Due to the short median survival time and poor prognosis of IPF, it is particularly urgent to find new IPF biomarkers. Previous studies have shown that basement membranes (BMs) are associated with the development of IPF and tumor metastasis. However, there is still a lack of research on BMs-related genes in IPF. Therefore, we investigated the expression level of BMs genes in IPF and control groups, and explored their potential as biomarkers for IPF diagnosis. In this study, the GSE32537 and GSE53845 datasets were used as training sets, while the GSE24206, GSE10667 and GSE101286 datasets were used as validation sets. In the training set, seven immune biomarkers related to BMs were selected by differential expression analysis, machine learning algorithm (LASSO, SVM-RFE, Randomforest) and ssGSEA analysis. Further ROC analysis confirmed that seven BMs-related genes played an important role in IPF. Finally, four immune-related Hub genes (COL14A1, COL17A1, ITGA10, MMP7) were screened out. Then we created a logistic regression model of immune-related hub genes (IHGs) and used a nomogram to predict IPF risk. The nomogram model was evaluated to have good reliability and validity, and ROC analysis showed that the AUC value of IHGs was 0.941 in the training set and 0.917 in the validation set. Pan-cancer analysis showed that IHGs were associated with prognosis, immune cell infiltration, TME, and drug sensitivity in 33 cancers, suggesting that IHGs may be potential targets for intervention in human diseases including IPF and cancer.

Retinoic acid effects on in vitro palatal fusion and WNT signaling

Retinoic acid is the main active vitamin A derivate and a key regulator of embryonic development. Excess of retinoic acid can disturb palate development in mice leading to cleft palate. WNT signaling is one of the main pathways in palate development. We evaluated the effects of retinoic acid on palate fusion and WNT signaling in in vitro explant cultures. Unfused palates from E13.5 mouse embryos were cultured for 4 days with 0.5 μM, 2 μM or without retinoic acid. Apoptosis, proliferation, WNT signaling and bone formation were analyzed by histology and quantitative PCR. Retinoic acid treatment with 0.5 and 2.0 μM reduced palate fusion from 84% (SD 6.8%) in the controls to 56% (SD 26%) and 16% (SD 19%), respectively. Additionally, 2 μM retinoic acid treatment increased Axin2 expression. Retinoic acid also increased the proliferation marker Pcna as well as the number of Ki-67-positive cells in the palate epithelium. At the same time, the WNT inhibitors Dkk1, Dkk3, Wif1 and Sfrp1 were downregulated at least two-fold. Retinoic acid also down-regulated Alpl and Col1a2 gene expression. Alkaline phosphatase (ALP) activity was notably reduced in the osteogenic areas of the retinoic acid- treated palates. Our data suggest that retinoic acid impairs palate fusion and bone formation by upregulation of WNT signaling.

A novel epithelial-mesenchymal transition (EMT)-related gene signature of predictive value for the survival outcomes in lung adenocarcinoma

Lung adenocarcinoma (LUAD) is a remarkably heterogeneous and aggressive disease with dismal prognosis of patients. The identification of promising prognostic biomarkers might enable effective diagnosis and treatment of LUAD. Aberrant activation of epithelial-mesenchymal transition (EMT) is required for LUAD initiation, progression and metastasis. With the purpose of identifying a robust EMT-related gene signature (E-signature) to monitor the survival outcomes of LUAD patients. In The Cancer Genome Atlas (TCGA) database, least absolute shrinkage and selection operator (LASSO) analysis and cox regression analysis were conducted to acquire prognostic and EMT-related genes. A 4 EMT-related and prognostic gene signature, comprising dickkopf-like protein 1 (DKK1), lysyl oxidase-like 2 (LOXL2), matrix Gla protein (MGP) and slit guidance ligand 3 (SLIT3), was identified. By the usage of datum derived from TCGA database and Western blotting analysis, compared with adjacent tissue samples, DKK1 and LOXL2 protein expression in LUAD tissue samples were significantly higher, whereas the trend of MGP and SLIT3 expression were opposite. Concurrent with upregulation of epithelial markers and downregulation of mesenchymal markers, knockdown of DKK1 and LOXL2 impeded the migration and invasion of LUAD cells. Simultaneously, MGP and SLIT3 silencing promoted metastasis and induce EMT of LUAD cells. In the TCGA-LUAD set, receiver operating characteristic (ROC) analysis indicated that our risk model based on the identified E-signature was superior to those reported in literatures. Additionally, the E-signature carried robust prognostic significance. The validity of prediction in the E-signature was validated by the three independent datasets obtained from Gene Expression Omnibus (GEO) database. The probabilistic nomogram including the E-signature, pathological T stage and N stage was constructed and the nomogram demonstrated satisfactory discrimination and calibration. In LUAD patients, the E-signature risk score was associated with T stage, N stage, M stage and TNM stage. GSEA (gene set enrichment analysis) analysis indicated that the E-signature might be linked to the pathways including GLYCOLYSIS, MYC TARGETS, DNA REPAIR and so on. In conclusion, our study explored an innovative EMT based prognostic signature that might serve as a potential target for personalized and precision medicine.

Osteopontin-Targeted and PPARδ-Agonist-Loaded Nanoparticles Efficiently Reduce Atherosclerosis in Apolipoprotein E-/- Mice

Atherosclerosis is the leading cause of vascular pathologies and acute cardiovascular events worldwide. Early theranostics of atherosclerotic plaque formation is critical for the prevention of associated cardiovascular complications. Osteopontin (OPN) expression in vascular smooth muscle cells (VSMCs) has been reported as a promising molecular target for the diagnosis and treatment of atherosclerotic plaques. The PPARδ agonist GW1516 has been shown to inhibit VSMC migration and apoptosis. However, GW1516 has low aqueous solubility and poor oral bioavailability, which are major obstacles to its broad development and application. In this study, GW1516@NP-OPN, which is anti-OPN-targeted and loaded with the PPARδ agonist GW1516, was synthesized using a nanoprecipitation method. The uptake of GW1516@NP-OPN was examined using fluorescence microscopy and flow cytometry assay in VSMC in vitro models. Using the Transwell assay and acridine orange/ethidium bromide staining methods, we observed that the inhibition of VSMCS migration and apoptosis was significantly higher in cells treated with GW1516@NP-OPN than those treated with free GW1516. The western blot assay further confirmed that GW1516@NP-OPN can increase FAK phosphorylation and TGF-βprotein expression. The effect of NPs was further tested in vivo. The atherosclerotic lesion areas were greatly decreased by GW1516@NP-OPN compared with the free drug treatment in apolipoprotein E^-/- mice models. Consequently, our results showed that GW1516@NP-OPN stabilizes the PPARδ agonist aqueous formulation, improves its anti-plaque formation activities in vivo and in vitro, and can therefore be recommended for further development as a potential anti-atherosclerotic nanotherapy.

A Machine-Learning Approach to Developing a Predictive Signature Based on Transcriptome Profiling of Ground-Glass Opacities for Accurate Classification and Exploring the Immune Microenvironment of Early-Stage LUAD

Screening for early-stage lung cancer with low-dose computed tomography is recommended for high-risk populations; consequently, the incidence of pure ground-glass opacity (pGGO) is increasing. Ground-glass opacity (GGO) is considered the appearance of early lung cancer, and there remains an unmet clinical need to understand the pathology of small GGO (&lt;1 cm in diameter). The objective of this study was to use the transcriptome profiling of pGGO specimens &lt;1 cm in diameter to construct a pGGO-related gene risk signature to predict the prognosis of early-stage lung adenocarcinoma (LUAD) and explore the immune microenvironment of GGO. pGGO-related differentially expressed genes (DEGs) were screened to identify prognostic marker genes with two machine learning algorithms. A 15-gene risk signature was constructed from the DEGs that were shared between the algorithms. Risk scores were calculated using the regression coefficients for the pGGO-related DEGs. Patients with Stage I/II LUAD or Stage IA LUAD and high-risk scores had a worse prognosis than patients with low-risk scores. The prognosis of high-risk patients with Stage IA LUAD was almost identical to that of patients with Stage II LUAD, suggesting that treatment strategies for patients with Stage II LUAD may be beneficial in high-risk patients with Stage IA LUAD. pGGO-related DEGs were mainly enriched in immune-related pathways. Patients with high-risk scores and high tumor mutation burden had a worse prognosis and may benefit from immunotherapy. A nomogram was constructed to facilitate the clinical application of the 15-gene risk signature. Receiver operating characteristic curves and decision curve analysis validated the predictive ability of the nomogram in patients with Stage I LUAD in the TCGA-LUAD cohort and GEO datasets.

KRT15 promotes colorectal cancer cell migration and invasion through β-catenin/MMP-7 signaling pathway

KRT15 has been reported to act as an oncogene in colorectal cancer. However, whether KRT15 promotes colorectal cancer migration and invasion remain unclear. In this study, western blot and qRT-PCR assay were used to determine the expression of KRT15 in colorectal cancer cells. Wound-healing and transwell migration assay were performed to assess the migration of colorectal cancer cells. Matrigel transwell invasion assay was employed to examine the invasion of colorectal cancer cells. We found that KRT15 was highly expressed in colorectal cancer cells. Ectopic expression of KRT15 dramatically promoted colorectal cancer cell migration and invasion. Conversely, silencing KRT15 remarkably suppressed the migration and invasion of colorectal cancer cells. Importantly, we found that MMP-7 was crucial for KRT15-induced migration and invasion of colorectal cancer cells. Knockdown of MMP-7 significantly diminished the migration and invasion induced by KRT15; overexpression of MMP-7 almost completely rescued the inhibitory effects of KRT15 shRNAs on colorectal cancer cell migration and invasion. In addition, by gain- and loss-of function, we confirmed that β-catenin was responsible for the increased expression of MMP-7 induced by KRT15 colorectal cancer cell lines. In conclusion, KRT15 promotes migration and invasion of colorectal cancer cell at least partly through β-catenin/MMP7 signaling pathway, suggesting KRT15 is a potential therapeutic target for patients with metastatic colorectal cancer.

Expression of Dickkopf-1 and Twist2 in Cervical Squamous Cell Carcinoma and Their Correlation with Vasculogenic Mimicry

Wnt/β-catenin signaling, epithelial-mesenchymal transition (EMT), and vasculogenic mimicry (VM) all exert important effects in tumors. Dickkopf-1 (DKK1) is an antagonist of the Wnt/β-catenin, Twist homolog 2 (Twist2) is a key EMT transcription factor involved in cancer cell migration and invasion, and VM participates in the progression and metastasis of a variety of cancers. However, the correlation of DKK1, Twist2, and VM in cervical squamous cell carcinoma(CSC) is still unclear. This study focuses on correlations among these factors as well as their correlation with clinicopathologic data and survival in CSC. DKK1, Twist2, and VM expressions were immunohistochemically examined in 116 CSC tissues and 37 normal cervical tissues. Furthermore, clinical data were processed. The expression levels of these three factors differed between CSC and normal tissues. VM was observed in CSC, but not in normal cervical tissues. Twist2 expression was high in CSC but low in normal cervical tissues, whereas DKK1 expression had the opposite pattern. Tumor cells with VM had a high expression of Twist2 and low expression of DKK1. In addition, DKK1 expression was negatively correlated with Twist2 expression. Analyzing the relationships of DKK1, Twist2, and VM with the data of patients with CSC revealed that DKK1 expression was negatively correlated with the clinical stage, degree of differentiation, depth of infiltration, and lymph node metastasis of tumors. VM and Twist2 expression were positively correlated with the degree of differentiation, the depth of infiltration, and lymph node metastasis. The positive rate of VM was greater in stage II than in stage I. The patients who expressed VM and Twist2 had a reduced overall survival (OS) when compared with patients not expressing these proteins. However, the patients who expressed DKK1 had an increased OS when compared with patients who did not show any DKK1 expression. Multivariate analysis indicated that the expressions of DKK1, Twist2, and VM were prognostic factors for CSC. VM and the expression of DKK1 and Twist2 can be the potential prognostic biomarkers and therapeutic targets for CSC.

S100A4/TCF Complex Transcription Regulation Drives Epithelial-Mesenchymal Transition in Chronic Sinusitis Through Wnt/GSK-3β/β-Catenin Signaling

Epithelial-mesenchymal transition (EMT) is thought to be involved in the tissue remodeling and long-term inflammatory process of chronic sinusitis (CRS), but the driving mechanism is still unclear. Using high-resolution mass spectrometry, we performed a proteomic screen of CRS nasal mucosal tissue to identify differentially expressed proteins. Data are available via ProteomeXchange with identifier PXD030884. Specifically, we identified S100 calcium binding protein A4 (S100A4), an effective factor in inflammation-related diseases, and its downstream protein closely related to tissue fibrosis collagen type I alpha 1 chain (COL1A1), which suggested its involvement in nasal mucosal tissue remodeling. In addition, stimulation of human nasal epithelial cells (HNEpCs) with lipopolysaccharide (LPS) mimicked the inflammatory environment of CRS and showed that S100A4 is involved in regulating EMT and thus accelerating tissue remodeling in the nasal mucosa, both in terms of increased cell motility and overexpression of mesenchymal-type proteins. Additionally, we further investigated the regulation mechanism of S100A4 involved in EMT in CRS. Our research results show that in the inflammatory environment of CRS nasal mucosal epithelial cells, TCF-4 will target to bind to S100A4 and regulate its transcription. The transcription of S100A4 in turn affects the execution of the important signaling pathway in EMT, the Wnt/GSK-3β/β-catenin pathway, through the TCF-4/β-catenin complex. In conclusion, this study confirmed that the expression of S100A4 was significantly increased during the progressive EMT process of CRS mucosal epithelial cells, and revealed that the transcriptional regulation of S100A4 plays an important role in the occurrence and development of EMT. This finding will help us to better understand the pathogenesis behind the remodeling in CRS patients, and identify target molecules for the treatment of CRS.

Epigenetic inactivation of ACAT1 promotes epithelial-mesenchymal transition of clear cell renal cell carcinoma

BACKGROUND

Acetyl-CoA acyltransferase 1 (ACAT1) is a key enzyme catalyzing the production of mitochondrial ketone bodies. We have shown that ACAT1 is down-regulated in kidney renal clear cell carcinoma (KIRC) previously.

OBJECTIVE

To investigate the reasons for downregulation of ACAT1 in KIRC and explore the underlying mechanisms involved in metastatic inhibition regulated by ACAT1.

METHODS

The Gene Expression Omnibus (GEO) database was queried for meta-analysis of ACAT1 mRNA expression in KIRC. The UALCAN website was used to compare the methylation levels of the ACAT1 promoter region in KIRC and normal tissues. RT-qPCR was used to quantitate ACAT1 transcription levels. The GCBI and Tarbase V.8 databases were used to predict miRNAs that may target the mRNA of ACAT1. The correlation between mRNA expression of ACAT1, MMP7 (matrix metallopeptidase 7), CDH1 (E-cadherin), EpCAM (epithelial cell adhesion molecule), and VIM (vimentin) was analyzed. Extracellular MMP7 protein was quantitated using an ELISA assay.

RESULTS

The methylation level of the ACAT1 promoter region in KIRC was significantly higher than that in the normal kidney tissues. The ACAT1 mRNA expression in the KIRC cell lines was restored after treatment with 5-aza-dC (p < 0.05). MiR-21-5p is a conserved microRNA targeting ACAT1. It is expressed at a significantly higher level in KIRC than in normal tissues (p < 0.001). MiR-21-5p miRNA expression negatively correlates with ACAT1 mRNA expression. The expression of miR-21-5p is higher at the T3-T4 stages and in the histologic grades G3-G4. Patients with high miR-21-5p expression tended to have lower overall survival, suggesting that miR-21-5p could serve as a potentially valuable diagnostic biomarker for KIRC (AUC = 0.957; p < 0.001). A mimetic of miR-21-5p inhibited the expression of ACAT1 mRNA and protein. In addition, ACAT1 mRNA expression positively correlates with CDH1 and EpCAM but is negatively correlated with VIM. Overexpression of ACAT1 suppresses the secretion of MMP7 in KIRC cells.

CONCLUSION

Expression of ACAT1 in KIRC is controlled at two levels, firstly by the hypermethylation of the ACAT1 promoter region and secondly by overexpression of miR-21-5p. Downregulation of ACAT1 expression correlates with epithelial-mesenchymal transition (EMT).

3-D vascularized breast cancer model to study the role of osteoblast in formation of a pre-metastatic niche

Breast cancer cells (BCCs) preferentially metastasize to bone. It is known that BCCs remotely primes the distant bone site prior to metastasis. However, the reciprocal influence of bone cells on the primary tumor is relatively overlooked. Here, to study the bone-tumor paracrine influence, a tri-cellular 3-D vascularized breast cancer tissue (VBCTs) model is engineered which comprised MDA-MB231, a triple-negative breast cancer cells (TNBC), fibroblasts, and endothelial cells. This is indirectly co-cultured with osteoblasts (OBs), thereby constituting a complex quad-cellular tumor progression model. VBCTs alone and in conjunction with OBs led to abnormal vasculature and reduced vessel density but enhanced VEGF production. A total of 1476 significantly upregulated and 775 downregulated genes are identified in the VBCTs exposed to OBs. HSP90N, CYCS, RPS27A, and EGFR are recognized as upregulated hub-genes. Kaplan Meier plot shows HSP90N to have a significant outcome in TNBC patient survivability. Furthermore, compared to cancer tissues without vessels, gene analysis recognized 1278 significantly upregulated and 566 downregulated genes in VBCTs. DKK1, CXCL13, C3 protein and BMP4 are identified to be downregulated hub genes in VBCTs. Together, a multi-cellular breast cancer model and culture protocols are established to study pre-metastatic events in the presence of OBs.

High Serum Levels of Wnt Signaling Antagonist Dickkopf-Related Protein 1 Are Associated with Impaired Overall Survival and Recurrence in Esophageal Cancer Patients

Simple Summary

Dickkopf-related protein 1 (DKK1), an antagonist of the canonical Wnt pathway has been the subject of research for many years. Especially in gastrointestinal cancers, research suggests a pivotal role of DKK1. In order to understand the role of DKK1 in esophageal cancer, we analyzed blood samples of esophageal cancer patients for their DKK1 levels and retrospectively analyzed the clinicopathological data. In our study cohort, we observed a negative prognostic role of high DKK1 serum levels with respect to overall survival in esophageal cancer patients. These data may suggest serum DKK1 as a novel biomarker for improved risk stratification and treatment monitoring in esophageal cancer patients.

Abstract

Dickkopf-related protein 1 (DKK1), an antagonist of the canonical Wnt pathway, has received tremendous attention over the past years as its dysregulation is said to be critically involved in a wide variety of gastrointestinal cancers. However, the potential clinical implications of DKK1 remain poorly understood. Although multimodal treatment options have been implemented over the past years, esophageal cancer (EC) patients still suffer from poor five-year overall survival rates ranging from 15% to 25%. Especially prognostic factors and biomarkers for risk stratification are lacking to choose the most beneficial treatment out of the emerging landscape of different treatment options. In this study, we analyzed the serum DKK1 (S-DKK1) levels of 91 EC patients prior to surgery in a single center study at the University Medical Center Hamburg-Eppendorf by enzyme-linked immunosorbent assay. High levels of S-DKK1 could be especially observed in patients suffering from esophageal adenocarcinoma which may promote the hypothesis of a crucial role of DKK1 in inflammation. S-DKK1 levels of ≥5800 pg/mL were shown to be associated with unfavorable five-year survival rates and the presence of CTCs. Interestingly, significantly lower S-DKK1 levels were detected in patients after neoadjuvant treatment, implying that S-DKK1 may serve as a useful biomarker for treatment monitoring. Multivariate analysis identified S-DKK1 as an independent prognostic marker with respect to overall survival in EC patients with a hazard ratio of 2.23. In conclusion, our data implicate a negative prognostic role of DKK1 with respect to the clinical outcome in EC patients. Further prospective studies should be conducted to implement S-DKK1 into the clinical routine for risk stratification and treatment monitoring.

SH3PXD2A-AS1/miR-330-5p/UBA2 ceRNA network mediates the progression of colorectal cancer through regulating the activity of the Wnt/β-catenin signaling pathway

Long non-coding RNAs have important roles in the occurrence and progression of various cancers. However, the molecular mechanism of lncRNAs in colorectal cancer (CRC) is not well illustrated. Thus, we used bioinformatics methods to find potential lncRNAs associated with CRC progression, and chose SH3PXD2A-AS1 as a candidate for further analysis. The roles of SH3PXD2A-AS1 in CRC cells were determined by CCK-8, transwell invasion, wound healing and flow cytometry assays. Besides, we established the CRC tumor models in nude mice to study the effect of SH3PXD2A-AS1 on the tumor growth. Based on the ceRNA hypothesis, we used miRDB and miRTarBase websites to identify the SH3PXD2A-AS1-related ceRNA regulatory network, and measured the roles of this network in CRC cells. The results revealed that the expression profiles of SH3PXD2A-AS1 from GEO and TCGA databases showed an aberrant high level in CRC tissues compared with colorectal normal tissues. SH3PXD2A-AS1 over-expression was also found in CRC cells. SH3PXD2A-AS1 knockdown inhibited the CRC cellular proliferation, invasion and migration but induced apoptosis. Besides, SH3PXD2A-AS1 knockdown also suppressed the growth of CRC tumors. Furthermore, SH3PXD2A-AS1 could function as a ceRNA of miR-330-5p. Additionally, UBA2 was proved to be a target gene of miR-330-5p. Moreover, SH3PXD2A-AS1 knockdown downregulated UBA2 expression through sponging miR-330-5p to inactivate the Wnt/β-catenin signaling pathway, thereby inhibiting the cell growth and promoting apoptosis. Therefore, the SH3PXD2A-AS1/miR-330-5p/UBA2 network could regulate the progression of CRC through the Wnt/β-catenin pathway. These findings offer new sights for understanding the pathogenesis of CRC and provide potential biomarkers for CRC treatment.

MEIS2 Is an Adrenergic Core Regulatory Transcription Factor Involved in Early Initiation of TH-MYCN-Driven Neuroblastoma Formation

Simple Summary

Neuroblastoma is a pediatric tumor originating from the sympathetic nervous system responsible for 10–15% of all childhood cancer deaths. Half of all neuroblastoma patients present with high-risk disease, of which nearly 50% relapse and die of their disease. In addition, standard therapies cause serious lifelong side effects and increased risk for secondary tumors. Further research is crucial to better understand the molecular basis of neuroblastomas and to identify novel druggable targets. Neuroblastoma tumorigenesis has to this end been modeled in both mice and zebrafish. Here, we present a detailed dissection of the gene expression patterns that underlie tumor formation in the murine TH-MYCN-driven neuroblastoma model. We identified key factors that are putatively important for neuroblastoma tumor initiation versus tumor progression, pinpointed crucial regulators of the observed expression patterns during neuroblastoma development and scrutinized which factors could be innovative and vulnerable nodes for therapeutic intervention.

Abstract

Roughly half of all high-risk neuroblastoma patients present with MYCN amplification. The molecular consequences of MYCN overexpression in this aggressive pediatric tumor have been studied for decades, but thus far, our understanding of the early initiating steps of MYCN-driven tumor formation is still enigmatic. We performed a detailed transcriptome landscaping during murine TH-MYCN-driven neuroblastoma tumor formation at different time points. The neuroblastoma dependency factor MEIS2, together with ASCL1, was identified as a candidate tumor-initiating factor and shown to be a novel core regulatory circuit member in adrenergic neuroblastomas. Of further interest, we found a KEOPS complex member (gm6890), implicated in homologous double-strand break repair and telomere maintenance, to be strongly upregulated during tumor formation, as well as the checkpoint adaptor Claspin (CLSPN) and three chromosome 17q loci CBX2, GJC1 and LIMD2. Finally, cross-species master regulator analysis identified FOXM1, together with additional hubs controlling transcriptome profiles of MYCN-driven neuroblastoma. In conclusion, time-resolved transcriptome analysis of early hyperplastic lesions and full-blown MYCN-driven neuroblastomas yielded novel components implicated in both tumor initiation and maintenance, providing putative novel drug targets for MYCN-driven neuroblastoma.

EPRS/GluRS promotes gastric cancer development via WNT/GSK-3β/β-catenin signaling pathway

BACKGROUND

Glutamyl-prolyl-tRNA synthetase (EPRS/GluRS) is primarily part of the multi-synthetase complex that may play a key role in cancer development. However, the biological function, molecular mechanism, and inhibitor of EPRS have not been investigated in gastric cancer (GC).

METHODS

Immunohistochemistry was performed to detect the expression of EPRS in human gastric tumor tissues. Knocking down of EPRS, cell-derived xenograft mouse model, and patient-derived xenograft mouse model was used to identify the biological function of EPRS. Immunoprecipitation was applied to elucidate the interaction between EPRS and SCYL2. Computer docking model and multiple in vitro and in vivo experiments were conducted to discover EPRS inhibitors.

RESULTS

Here, we report that EPRS is frequently overexpressed in GC tissues compared to that adjacent controls and its overexpression predicts poor prognosis in GC patients. Functionally, high expression of EPRS positively co-relates with GC development both in vitro and in vivo. Mechanistically, EPRS directly binds with SCYL2 to enhance the activation of WNT/GSK-3β/β-catenin signaling pathway and the accumulation of β-catenin in the nuclear, leading to GC cell proliferation and tumor growth. Moreover, we identified that xanthoangelol (XA) and 4-hydroxyderricin (4-HD) can directly bind to EPRS to block WNT/GSK-3β/β-catenin signaling pathway. More importantly, XA and 4-HD restrain gastric cancer patient-derived xenograft tumor growth and Helicobacter pylori combined with alcohol-induced atrophic gastritis and gastric tumorigenesis.

CONCLUSION

These findings unveil a promising strategy for GC prevention and therapy by targeting EPRS-mediated WNT/GSK-3β/β-catenin cascades. Moreover, XA and 4-HD may be effective reagents used for GC prevention and therapy.

Assessment of Phenylboronic Acid Nitrogen Mustards as Potent and Selective Drug Candidates for Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) has limited treatment options and the worst prognosis among all types of breast cancer. We describe two prodrugs, namely, CWB-20145 (1) and its methyl analogue FAN-NM-CH3 (2) that reduced the size of TNBC-derived tumors. The DNA cross-linking of nitrogen mustard prodrugs 1 and 2 was superior to that of chlorambucil and melphalan once activated in the presence of H2O2. The cellular toxicity of 1 and 2 was demonstrated in seven human cancer cell lines. The TNBC cell line MDA-MB-468 was particularly sensitive toward 1 and 2. Compound 2 was 10 times more cytotoxic than chlorambucil and 16 times more active than melphalan. An evaluation of the gene expression demonstrated an upregulation of the tumor suppressor genes p53 and p21 supporting a transcriptional mechanism of a reduced tumor growth. Pharmacokinetic studies with 1 showed a rapid conversion of the prodrug. The introduction of a methyl group generated 2 with an increased half-life. An in vivo toxicity study in mice demonstrated that both prodrugs were less toxic than chlorambucil. Compounds 1 and 2 reduced tumor growth with an inhibition rate of more than 90% in athymic nude mice xenografted with MDA-MB-468 cells. Together, the in vivo investigations demonstrated that treatment with 1 and 2 suppressed tumor growth without affecting normal tissues in mice. These phenylboronic acid nitrogen mustard prodrugs represent promising drug candidates for the treatment of TNBC. However, the mechanisms underlying their superior in vivo activity and selectivity as well as the correlation between H2O2 level and in vivo efficacy are not yet fully understood.

Roles of matrix metalloproteinase-7 (MMP-7) in cancer

Matrix metalloproteinase-7 (MMP-7) is a small proteolytic enzyme that secretes zinc and calcium endopeptidases. It can degrade a variety of extracellular matrix substrates and other substrates and plays important regulatory roles in many human pathophysiological processes. Since its discovery, MMP-7 has been recognized as a regulatory protein in wound healing, bone growth, and remodeling. Later, MMP-7 was reported to regulate the occurrence and development of cancers and mediate the proliferation, differentiation, metastasis, and invasion of several types of cancer cells via various mechanisms. Thus, matrix metalloproteinase-7 may be a promising tumor biomarker and therapeutic target. The expression of MMP-7 correlates with the clinical characteristics of cancer patients, and its expression profile is a new diagnostic and prognostic biomarker for a variety of human diseases. Hence, manipulating the expression or function of MMP-7 may be a potential treatment strategy for different diseases including cancers. This review summarizes the role played by MMP-7 in carcinogenesis of several human cancers, underlying mechanisms, and its clinical significance of the occurrence and development of cancers.

CT23 knockdown attenuating malignant behaviors of hepatocellular carcinoma cell is associated with upregulation of metallothionein 1

The cancer-testis antigen 23 (CT23) gene has been reported in association with the pathogenesis and progress of hepatocellular carcinoma (HCC). However, the alterations of gene expression profiling induced by CT23 knockdown in HCC cells remains largely unknown. In this study, the RNA interfering (RNAi) method was used to silence CT23 expression in BEL-7404 cells. Microarray analysis was performed on mRNA extracted from the CT23 knockdown cells and the control cells to determine the alterations of gene expression profiles. The result showed a total of 1051 genes expressed differentially (two-fold change), including 470 genes upregulated and 581 gene downregulated in the CT23 knockdown cells. A bioinformatic analysis showed that the functional differentially expressed genes (DEGs) were linked to cell proliferation, migration, and apoptosis, and metallothionein 1 (MT1) attained the maximum enrichment scores in functional annotation, classification, and pathway analysis of DEGs. Furthermore, Western blot analysis and cell behaviors assays verified that CT23 modulates cell proliferation, migration, and apoptosis by regulating MT1 expression in HCC cells and non-neoplastic hepatocytes. In summary, downregulated CT23 gene in BEL-7404 cells might change the expressions of carcinogenesis and progression related genes in HCC by upregulating MT1 expression, which would provide insight into searching for a novel therapeutic target for HCC.

The action of hyaluronan in functional properties, morphology and expression of matrix effectors in mammary cancer cells depends on its molecular size

Breast cancer constitutes a heterogeneous disease. The expression profiles of estrogen receptors (ERs), as well as the expression patterns of extracellular matrix (ECM) macromolecules, determine its development and progression. Hyaluronan (HA) is an ECM molecule that regulates breast cancer cells' properties in a molecular size-dependent way. Previous studies have shown that 200-kDa HA fragments modulate the functional properties, morphology, and expression of several matrix mediators of the highly metastatic ERα^- /ERβ⁺ MDA-MB-231 cells. In order to evaluate the effects of HA fragments (< 10, 30 and 200-kDa) in ERβ-suppressed breast cancer cells, the shERβ MDA-MB-231 cells were used. These cells are less aggressive when compared with MDA-MB-231 cells. To this end, the functional properties, the morphology, and the expression of the molecules associated with breast cancer cells metastatic potential were studied. Notably, both cell proliferation and invasion were significantly reduced after treatment with 200-kDa HA. Moreover, as assessed by scanning electron microscopy, 200-kDa HA affected cellular morphology, and as assessed by qPCR, upregulated the epithelial marker Ε-cadherin. The expression profiles of ECM mediators, such as HAS2, CD44, and MMP7, were also altered. On the other hand, cellular migration and the expression levels of syndecan-4 (SDC-4) were not significantly affected in contrast to our observations regarding MDA-MB-231 cells. These novel data demonstrate that the molecular size of the HA determines its effects on ERβ-suppressed breast cancer cells and that 200-kDa HA exhibits antiproliferative effects on these cells. A deeper understanding of this mechanism may contribute to the development of therapeutic strategies against breast cancer.

Free CA125 promotes ovarian cancer cell migration and tumor metastasis by binding Mesothelin to reduce DKK1 expression and activate the SGK3/FOXO3 pathway

Objective: CA125/MUC16 is an O-glycosylated protein that is expressed on the surfaces of ovarian epithelial cells. This molecule is a widely used tumor-associated marker for diagnosis of ovarian cancer. Recently, CA125 was shown to be involved in ovarian cancer metastasis. The purpose of this study was to investigate the mechanism of CA125 during ovarian cancer metastasis.

Methods: We analyzed the Oncomine and CSIOVDB databases to determine the expression levels of DKK1 in ovarian cancer. DKK1 expression levels were upregulated or downregulated and applied with CA125 to Transwell and Western blot assays to ascertain the underlying mechanism by which CA125 stimulates cell migration via the SGK3/FOXO3 pathway. Anti-mesothelin antibodies (anti-MSLN) were used to block CA125 stimulation. Then the expression levels of DKK1were tested by enzyme-linked immunosorbent assay (ELISA) to eliminate the blocking effect of anti-MSLN to CA125 stimulation. Xenograft mouse models were used to detect the effects of CA125 and anti-MSLN on ovarian cancer metastasis in vivo.

Results: DKK1 levels were downregulated in ovarian tumor tissues according to the analyses of two databases and significantly correlated with FIGO stage, grade and disease-free survival in ovarian cancer patients. DKK1 levels were downregulated by CA125 stimulation in vitro. Overexpression of DKK1 reversed the ability of exogenous CA125 to mediate cell migration by activating the SGK3/FOXO3 signaling pathway. Anti-MSLN abrogated the DKK1 reduction and increased the apoptosis of ovarian cancer cells. The use of anti-MSLN in xenograft mouse models significantly reduced tumor growth and metastasis accelerated by CA125.

Conclusions: These experiments revealed that the SGK3/FOXO3 pathway was activated, wherein decreased expression of DKK1 was caused by CA125, which fuels ovarian cancer cell migration. Mesothelin is a potential therapeutic target for the treatment of ovarian cancer metastasis.

circRNA hsa_circ_0018414 inhibits the progression of LUAD by sponging miR-6807-3p and upregulating DKK1

Lung adenocarcinoma (LUAD) is a subtype of lung cancer with a high incidence and mortality all over the world. In recent years, circular RNAs (circRNAs) have been verified to be a novel subtype of noncoding RNAs that exert vital functions in various cancers. Our research was designed to investigate the role of circ_0018414 in LUAD. We first observed that circ_0018414 was downregulated in LUAD tissues and cells. Also, low expression of circ_0018414 predicted unfavorable prognosis of LUAD patients. Then, upregulation of circ_0018414 repressed cell proliferation and stemness, while promoting cell apoptosis, in LUAD. Moreover, circ_0018414 overexpression enhanced the expression of its host gene, dickkopf WNT signaling pathway inhibitor 1 (DKK1), therefore inactivating the Wnt/β-catenin pathway. Additionally, circ_0018414 could sponge miR-6807-3p to protect DKK1 mRNA from miR-6807-3p-induced silencing, leading to DKK1 upregulation in LUAD cells. Finally, rescue assays proved that circ_0018414 inhibited the progression of LUAD via the miR-6807-3p/DKK1 axis-inactivated Wnt/β-catenin pathway. The findings in our work indicated circ_0018414 as a tumor inhibitor in LUAD, which might provide a new perspective for LUAD treatment.

Spontaneous regression of micro-metastases following primary tumor excision: a critical role for primary tumor secretome

BACKGROUND

Numerous case studies have reported spontaneous regression of recognized metastases following primary tumor excision, but underlying mechanisms are elusive. Here, we present a model of regression and latency of metastases following primary tumor excision and identify potential underlying mechanisms.

RESULTS

Using MDA-MB-231HM human breast cancer cells that express highly sensitive luciferase, we monitored early development stages of spontaneous metastases in BALB/c nu/nu mice. Removal of the primary tumor caused marked regression of micro-metastases, but not of larger metastases, and in vivo supplementation of tumor secretome diminished this regression, suggesting that primary tumor-secreted factors promote early metastatic growth. Correspondingly, MDA-MB-231HM-conditioned medium increased in vitro tumor proliferation and adhesion and reduced apoptosis. To identify specific mediating factors, cytokine array and proteomic analysis of MDA-MB-231HM secretome were conducted. The results identified significant enrichment of angiogenesis, growth factor binding and activity, focal adhesion, and metalloprotease and apoptosis regulation processes. Neutralization of MDA-MB-231HM-secreted key mediators of these processes, IL-8, PDGF-AA, Serpin E1 (PAI-1), and MIF, each antagonized secretome-induced proliferation. Moreover, their in vivo simultaneous blockade in the presence of the primary tumor arrested the development of micro-metastases. Interestingly, in the METABRIC cohort of breast cancer patients, elevated expression of Serpin E1, IL-8, or the four factors combined predicted poor survival.

CONCLUSIONS

These results demonstrate regression and latency of micro-metastases following primary tumor excision and a crucial role for primary tumor secretome in promoting early metastatic growth in MDA-MB-231HM xenografts. If generalized, such findings can suggest novel approaches to control micro-metastases and minimal residual disease.

Circulating osteocyte-related biomarkers (vitamin D, sclerostin, dickkopf-1), hepcidin, and oxidative stress markers in early breast cancer: Their impact in disease progression and outcome

Breast cancer (BC) is a major concern to female health worldwide. We assessed the circulating osteocyte-related biomarkers, hepcidin, and oxidative stress status among early-stage BC patients in aspects of clinical severity and impact on the outcome. The study incorporated 73 patients categorized into 57 early-stage BC and 16 benign breast diseases and 30 healthy controls. Serum 25-hydroxyvitamin D [25(OH)D], sclerostin (SOST), dickkopf-1(DKK1), and hepcidin were measured using ELISA, while, serum oxidative stress markers were assessed by spectrophotometry. Our results show that patients with BC showed significant increase in the mean levels of DKK1, SOST, hepcidin, and LPER and significant decrease in the mean levels of 25(OH)D, SOD, GPx, and Hb when compared with controls and benign breast diseases. Significantly higher DKK1, hepcidin, and SOD levels among benign breast diseases were found in comparison to control group. There were significantly lower levels of 25(OH)D, SOD, and Hb and significantly higher levels of SOST, DKK1, hepcidin, No, and LPER with advanced grade. Lower levels of 25(OH)D, SOD and higher levels of SOST, hepcidin were observed with increasing the malignant stage. Reduced levels of 25(OH)D, and SOD were significantly associated with poor prognosis and were strong predictors among BC. There were significant negative correlations between 25(OH)D with LPER, SOST, and hepicidin. We conclude that low 25(OH)D, high SOST, DKK1, and hepcidin, and dysregulated oxidative stress could be helpful in early detection and assessment of BC. 25(OH)D, and SOD were the most relevant to tumor progression and prognosis which indicate a significant role in the BC pathogenesis and could be promising targets in management. Our research paves the way to disrupt vicious circle between these biomarkers to obtain the best care of BC.

lncRNA PART1 Promotes Breast Cancer Cell Progression by Directly Targeting miR-4516

Introduction

Breast cancer is a serious threat to human health. It is meaningful to study the pathogenesis of breast cancer. lncRNAs have been found to play vital roles in numerous biological processes including development, immunology and cancer.

Methods

qRT-PCR was performed to examine the expressions of PART1 and miR-4516. CCK-8 assay, colony formation assay and transwell assay were used to examine the progression of breast cancer cells.

Results

In this study, we showed that lncRNA PART1 was highly expressed in breast cancer cells. Knockdown of PART1 induced decreased proliferation, invasion and migration of breast cancer cells. Moreover, we found that PART1 can bind to miR-4516 directly. We also found that inhibition of miR-4516 could rescue the decreased proliferation, migration and invasion of breast cancer cells induced by knockdown of PART1.

Discussion

lncRNA PART1 and miR-4516 were proven to be involved in the progression of many cancers. However, the roles of lncRNA PART1 and miR-4516 in the regulation of breast cancer remain unknown. Here, we demonstrated that PART1 can bind to miR-4516 to decrease the expression of miR-4516 and promote the development of breast cancer.

LncRNA Linc-PINT inhibits miR-523-3p to hamper retinoblastoma progression by upregulating Dickkopf-1 (DKK1)

Emerging evidences indicated that long non-coding RNAs (LncRNAs) regulated the pathogenesis of retinoblastoma (RB). However, up until now, the role of LncRNA Linc-PINT in the regulation of RB progression is still largely unknown. The present study identified LncRNA Linc-PINT as a tumor suppressor to hinder RB development by regulating miR-523-3p/Dickkopf-1 (DKK1) axis. Mechanistically, Linc-PINT was low-expressed, while miR-523-3p was high-expressed in RB cells, compared to the normal retinal epithelial cells (ARPE-19). Further gain- and loss-function experiments verified that both upregulation of Linc-PINT and miR-523-3p downregulation slowed down cell growth, invasion and migration, and promoted cell apoptosis in RB cells, but Linc-PINT ablation and miR-523-3p overexpression promoted malignant phenotypes in RB cells. In addition, the dual-luciferase reporter gene system and RNA pull-down assay validated that Linc-PINT positively regulated DKK1 expressions by sponging miR-523-3p, and Linc-PINT inhibited RB progression by regulating miR-523-3p/DKK1 axis. Functionally, we found that both miR-523-3p overexpression and DKK1 silence abrogated the anti-cancer effects of overexpressed Linc-PINT on RB cells. Finally, Linc-PINT inhibited tumorigenicity of RB cells in xenograft mice models. In general, analysis of the data suggested that Linc-PINT inhibited miR-523-3p to upregulate DKK1, resulting in the inhibition of RB, and we demonstrated that Linc-PINT and miR-523-3p could be utilized as potential diagnostic and therapeutic biomarkers for RB in clinic.