A central role for cadherin signaling in cancer

Novel germline and somatic variants in familial and sporadic meningioma genes

Meningiomas arise from arachnoid cells in the meninges surrounding the brain and spinal cord and are attributed to NF2 pathogenic variants in, approximately 60% of cases. Using exome sequencing, we found heterozygous germline variants in nine potential novel meningioma genes across four families and four sporadic cases. We then screened for germline and somatic variants in these genes and 11 known meningioma genes in 76 sporadic meningiomas blood/tumor pairs. We identified 18 germline and 58 somatic variants in 18 of the 20 genes, including seven of our newly proposed meningioma genes: CSMD3, EXTL3, FAT3, RAB44, RARA, RECQL4, and TNRC6A. Chromosomal abnormalities were identified in 39 of 49 tumors that also carried germline or somatic variants, with 71.8% encompassing NF2. This study provides potential novel genetic risk factors of meningiomas appropriate for further exploration from the greater scientific community and pathways to consider in the design of future therapeutic approaches.

Intervention of a Communication Between PI3K/Akt and β-Catenin by (-)-Epigallocatechin-3-Gallate Suppresses TGF-β1-Promoted Epithelial-Mesenchymal Transition and Invasive Phenotype of NSCLC Cells

The epithelial-mesenchymal transition (EMT) assists in the acquisition of invasiveness, relapse, and resistance in non-small cell lung cancer (NSCLC) and can be caused by the signaling of transforming growth factor-β1 (TGF-β1) through Smad-mediated or Smad-independent pathways. (-)-Epigallocatechin-3-gallate (EGCG), a multifunctional cancer-preventing bioconstituent found in tea polyphenols, has been shown to repress TGF-β1-triggered EMT in the human NSCLC A549 cell line by inhibiting the activation of Smad2 and Erk1/2 or reducing the acetylation of Smad2 and Smad3. However, its impact on the Smad-independent pathway remains unclear. Here, we found that EGCG, similar to LY294002 (a specific inhibitor of phosphatidylinositol 3-kinase [PI3K]), downregulated Akt activation and restored the action of glycogen synthase kinase-3β (GSK-3β), accompanied by TGF-β1-caused changes in hallmarks of EMT such as N-cadherin, E-cadherin, vimentin, and Snail in A549 cells. EGCG inhibited β-catenin expression and its nuclear localization caused by TGF-β1, suggesting that EGCG blocks the crosstalk between the PI3K/Akt/GSK-3β route and β-catenin. Furthermore, it was shown that EGCG suppressed TGF-β1-elicited invasive phenotypes of A549 cells, including invading and migrating activities, matrix metalloproteinase-2 (MMP-2) secretion, cell adhesion, and wound healing. In summary, we suggest that EGCG inhibits the induction of EMT by TGF-β1 in NSCLC not only through a Smad-dependent pathway, but also through the regulation of the PI3K/Akt/β-catenin signaling axis.

The Roles of Vitamin D Receptor (VDR) and CD8+ T-Lymphocytes in Acral and Mucosal Melanoma Invasion Depth

BACKGROUND

Acral and mucosal melanomas, the most common sun-shielded site melanoma subtypes in Asia and Indonesia, often yield poor prognoses. The invasion depth reflects their progressivity, and the pathogenesis is influenced by vitamin D receptor (VDR) status and CD8+ T-Lymphocyte amount. This study aims to determine the association between the invasion depth of acral and mucosal melanomas with their VDR and CD8+ immunoexpression.

METHODS

A cross-sectional observational study was conducted on 60 formalin-fixed paraffin-embedded (FPPE) samples, with equal representation in acral and mucosal melanoma groups from 2017 to 2021. The samples were assessed for the invasion depth and immunoexpression of VDR and CD8+. A chi-square test with an alternative Exact-Fisher analysis was used to determine the association between the variables in both subtype groups.

RESULTS

An association between VDR and CD8+ immunoexpression and invasion depth in acral melanoma (p value = 0.0001 and 0.009, respectively) was observed, while only VDR immunoexpression was associated with the invasion depth in mucosal melanoma (p-value =0.004). Interestingly, no association was found between CD8+ immunoexpression and the invasion depth in mucosal melanoma (p = 0.640).

CONCLUSION

The role of VDR and CD8+ T-lymphocytes are inversely associated with melanoma depth in acral melanoma, while only VDR is associated with melanoma depth in mucosal melanoma.

ETVs dictate hPSC differentiation by tuning biophysical properties

Stem cells maintain a dynamic dialog with their niche, integrating biochemical and biophysical cues to modulate cellular behavior. Yet, the transcriptional networks that regulate cellular biophysical properties remain poorly defined. Here, we leverage human pluripotent stem cells (hPSCs) and two morphogenesis models - gastruloids and pancreatic differentiation - to establish ETV transcription factors as critical regulators of biophysical parameters and lineage commitment. Genetic ablation of ETV1 or ETV1/ETV4/ETV5 in hPSCs enhances cell-cell and cell-ECM adhesion, leading to aberrant multilineage differentiation including disrupted germ-layer organization, ectoderm loss, and extraembryonic cell overgrowth in gastruloids. Furthermore, ETV1 loss abolishes pancreatic progenitor formation. Single-cell RNA sequencing and follow-up assays reveal dysregulated mechanotransduction via the PI3K/AKT signaling. Our findings highlight the importance of transcriptional control over cell biophysical properties and suggest that manipulating these properties may improve in vitro cell and tissue engineering strategies.

Oncology Clinical Trials Targeting Members of the Cadherin Superfamily: A Review

The cadherin superfamily of proteins is critical for cell-cell interactions and demonstrates tissue-specific expression profiles. In cancers, disruption of cell-cell adhesion is frequently associated with oncogenesis and metastasis. As such, these proteins have been the targets of multiple attempts to develop novel therapeutics in malignancy. This review article discusses prior and current clinical trials targeting the cadherin proteins.

Pharmacological, computational, and mechanistic insights into triptolide's role in targeting drug-resistant cancers

As a promising candidate for tackling drug-resistant cancers, triptolide, a diterpenoid derived from the Chinese medicinal plant Tripterygium wilfordii, has been developed. This review summarizes potential antitumor activities, including the suppression of RNA polymerase II, the suppression of heat shock proteins (HSP70 and HSP90), and the blockade of NF-kB signalling. Triptolide is the first known compound to target cancer cells specifically but spare normal cells, and it has success in treating cancers that are difficult to treat, including pancreatic, breast, and lung cancers. It acts against the tolerance mechanisms, including efflux pump upregulation, epithelial-mesenchymal transition, and cancer stem cells. Triptolide modulates important cascades, including PI3K/AKT/mTOR, enhancing the efficacy of conventional therapies. Nonetheless, its clinical application is constrained by toxicity and bioavailability challenges. Emerging drug delivery systems, such as nanoparticles and micellar formulations, are being developed to address these limitations. It has strong interactions with key anticancer targets, like PARP, as determined in preclinical and computational studies consistent with its mechanism of action. Early-phase clinical trials of Minnelide, a water-soluble derivative of triptolide, are promising, but additional work is necessary to optimize dosing, delivery, and safety. This comprehensive analysis demonstrates that triptolide may constitute a repurposed precision medicine tool to overcome tolerance in cancer therapy.

Histone Deacetylase 7-Derived 7-Amino Acid Peptide Increases Skin Wound Healing via Regulating Epidermal Fibroblast Proliferation and Migration

Due to the complexity of wound healing, how to achieve successful healing is a significant clinical challenge. In this study, we found that the histone deacetylase-7-derived 7-amino acid peptide (7A, MHSPGAD), especially its phosphorylated version 7Ap (MH[pSer]PGAD), increased dermal fibroblast cell HDFα proliferation and migration via elevated delta-catenin (CTNND1) serine phosphorylation-mediated beta-catenin (CTNNB) nuclear translocation and subsequent upregulation of c-Myc and cyclin D1 expression. 7Ap physically interacted with platelet-derived growth factor receptor (PDGFR) and increased PDGFR interaction with cyclin-dependent kinase 6 (CDK6). The PDGFR siRNA or CDK6 siRNA knockdown ablated 7AP-induced CTNND1 phosphorylation and subsequent c-Myc/cyclin D1 expression, indicating a novel 7Ap-PDGFR-CDK6-CTNND1/CTNNB signal pathway in regulating fibroblast proliferation and migration. Furthermore, 7Ap increased human umbilic vein endothelial cell proliferation and tube formation, suggesting an angiogenic effect. In a full-thickness excision wound rat model, the local administration of 50 ng/mL of 7Ap in hydrogel exerted a similar effect as 1 μg/mL vascular endothelial growth factor on accelerating wound healing, featured by enhanced fibroblast proliferation and migration, collagen deposition, and increased new vessel formation during the early phase of wound healing. Taken together, this study not only elicited a novel signal pathway in fibroblast proliferation but also paved an avenue to develop 7Ap as a treatment option for skin wound healing.

Exploring the impact of PDGFD in osteosarcoma metastasis through single-cell sequencing analysis

PURPOSE

The overall survival rate for metastatic osteosarcoma hovers around 20%. Responses to second-line chemotherapy, targeted therapies, and immunotherapies have demonstrated limited efficacy in metastatic osteosarcoma. Our objective is to validate differentially expressed genes and signaling pathways between non-metastatic and metastatic osteosarcoma, employing single-cell RNA sequencing (scRNA-seq) and additional functional investigations. We aim to enhance comprehension of metastatic mechanisms and potentially unveil a therapeutic target.

METHODS

scRNA-seq was performed on two primary osteosarcoma lesions (1 non-metastatic and 1 metastatic). Seurat package facilitated dimensionality reduction and cluster identification. Copy number variation (CNV) was predicted using InferCNV. CellChat characterized ligand-receptor-based intercellular communication networks. Differentially expressed genes underwent GO function enrichment analysis and GSEA. Validation was achieved through the GSE152048 dataset, which identified PDGFD-PDGFRB as a common ligand-receptor pair with significant contribution. Immunohistochemistry assessed PDGFD and PDGFRB expression, while multicolor immunofluorescence and flow cytometry provided insight into spatial relationships and the tumor immune microenvironment. Kaplan-Meier survival analysis compared metastasis-free survival and overall survival between high and low levels of PDGFD and PDGFRB. Manipulation of PDGFD expression in primary osteosarcoma cells examined invasion abilities and related markers.

RESULTS

Ten clusters encompassing osteoblasts, osteoclasts, osteocytes, fibroblasts, pericytes, endothelial cells, myeloid cells, T cells, B cells, and proliferating cells were identified. Osteoblasts, osteoclasts, and osteocytes exhibited heightened CNV levels. Ligand-receptor-based communication networks exposed significant fibroblast crosstalk with other cell types, and the PDGF signaling pathway was activated in non-metastatic osteosarcoma primary lesion. These results were corroborated by the GSE152048 dataset, confirming the prominence of PDGFD-PDGFRB as a common ligand-receptor pair. Immunohistochemistry demonstrated considerably greater PDGFD expression in non-metastatic osteosarcoma tissues and organoids, correlating with extended metastasis-free and overall survival. PDGFRB expression showed no significant variation between non-metastatic and metastatic osteosarcoma, nor strong correlations with survival times. Multicolor immunofluorescence suggested co-localization of PDGFD with PDGFRB. Flow cytometry unveiled a highly immunosuppressive microenvironment in metastatic osteosarcoma. Manipulating PDGFD expression demonstrated altered invasive abilities and marker expressions in primary osteosarcoma cells from both non-metastatic and metastatic lesions.

CONCLUSIONS

scRNA-seq illuminated the activation of the PDGF signaling pathway in primary lesion of non-metastatic osteosarcoma. PDGFD displayed an inhibitory effect on osteosarcoma metastasis, likely through the suppression of the EMT signaling pathway.

Transcriptomics-based anti-tuberculous mechanism of traditional Chinese polyherbal preparation NiuBeiXiaoHe intermediates

Background

Integrated traditional Chinese medicine and biomedicine is an effective method to treat tuberculosis (TB). In our previous research, traditional Chinese medicine preparation NiuBeiXiaoHe (NBXH) achieved obvious anti-TB effects in animal experiments and clinical practice. However, the action mechanism of NBXH has not been elucidated.

Method

Peripheral blood mononuclear cells (PBMCs) were collected to extract mRNA and differentially expressed (DE) genes were obtained using gene microarray technology. Finally, GEO databases and RT-qPCR were used to verify the results of expression profile.

Result

After MTB infection, most upregulated DE genes in mice were immune-related genes, including cxcl9, camp, cfb, c4b, serpina3g, and ngp. Downregulated DE genes included lrrc74b, sult1d1, cxxc4, and grip2. After treatment with NBXH, especially high-dose NBXH, the abnormal gene expression was significantly corrected. Some DE genes have been confirmed in multiple GEO datasets or in pulmonary TB patients through RT-qPCR.

Conclusion

MTB infection led to extensive changes in host gene expression and mainly caused the host's anti-TB immune responses. The treatment using high-dose NBXH partially repaired the abnormal gene expression, further enhanced the anti-TB immunity included autophagy and NK cell-mediated cytotoxicity, and had a certain inhibitory effect on overactivated immune responses.

CDH3 Is an Effective Serum Biomarker of Colorectal Cancer Distant Metastasis Patients

Few robust biomarkers are available for distant metastatic colorectal cancer (CRC) patients. Aberrant high expression of CDH3 has been reported in advanced CRC patients, but the value of CDH3 as a biomarker for the diagnosis and prognosis of distant metastatic CRC patients remains to be evaluated. In this study, we explored the serum levels of CDH3 in different stages of CRC patients and sought to determine whether serum CDH3 serves as an independent biomarker for distant metastatic CRC patients. We analyzed the serum CDH3 levels by ELISA in a cohort of CRCs (n=96) and normal controls (n=28). We compared the serum CDH3 levels between normal controls and different stages of CRCs. As a potential diagnostic marker of distant metastatic CRC, the specificity and sensitivity of serum CDH3 were evaluated. Multivariate analysis was also performed to determine whether serum CDH3 was an independent risk factor. Moreover, the changes of serum CDH3 levels were monitored and analyzed before and after palliative chemotherapy. Serum levels of CDH3, CA24-2, CA19-9, CA72-4, and CEA were significantly elevated in distant metastatic CRCs. CA24-2 (r=0.24, P=0.01), CA19-9 (r=0.20, P=0.03), CA72-4 (r=0.64, P<0.0001), and CEA (r=0.31, P=0.0012) all had a certain correlation with CDH3. After three cycles of palliative chemotherapy, levels of CDH3, CA24-2, CA19-9, CA72-4, and CEA of partial response CRCs were reduced to 38.8% (95% confidence interval [CI]: 30.95%-53.77%), 57.73% (95% CI: 2.085%-73.83%), 50.33% (95% CI: 9.935%-79.42%), 74.74% (95% CI: 25.21%-88.00%), and 59.16% (95% CI: 12.65%-83.56%) of baseline, respectively. The areas under the receiver operating characteristic curves of CDH3, CA24-2, CA19-9, CA72-4, and CEA with chemotherapy response were 0.900, 0.597, 0.635, 0.608, and 0.507, respectively. Serum CDH3 is an effective serum biomarker for the diagnosis of distant metastatic CRCs and monitoring response to palliative chemotherapy in distant metastatic CRCs.

TSP50 facilitates breast cancer stem cell-like properties maintenance and epithelial-mesenchymal transition via PI3K p110α mediated activation of AKT signaling pathway

BACKGROUND

Studies have confirmed that epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-like properties are conducive to cancer metastasis. In recent years, testes-specific protease 50 (TSP50) has been identified as a prognostic factor and is involved in tumorigenesis regulation. However, the role and molecular mechanisms of TSP50 in EMT and CSC-like properties maintenance remain unclear.

METHODS

The expression and prognostic value of TSP50 in breast cancer were excavated from public databases and explored using bioinformatics analysis. Then the expression of TSP50 and related genes was further validated by quantitative RT-PCR (qRT-PCR), Western blot, and immunohistochemistry (IHC). In order to investigate the function of TSP50 in breast cancer, loss- and gain-of-function experiments were conducted, both in vitro and in vivo. Furthermore, immunofluorescence (IF) and immunoprecipitation (IP) assays were performed to explore the potential molecular mechanisms of TSP50. Finally, the correlation between the expression of TSP50 and related genes in breast cancer tissue microarray and clinicopathological characteristics was analyzed by IHC.

RESULTS

TSP50 was negatively correlated with the prognosis of patients with breast cancer. TSP50 promoted CSC-like traits and EMT in both breast cancer cells and mouse xenograft tumor tissues. Additionally, inhibition of PI3K/AKT partly reversed TSP50-induced activation of CSC-like properties, EMT and tumorigenesis. Mechanistically, TSP50 and PI3K p85α regulatory subunit could competitively interact with the PI3K p110α catalytic subunit to promote p110α enzymatic activity, thereby activating the PI3K/AKT signaling pathway for CSC-like phenotypes maintenance and EMT promotion. Moreover, IHC analysis of human breast cancer specimens revealed that TSP50 expression was positively correlated with p-AKT and ALDH1 protein levels. Notably, breast cancer clinicopathological characteristics, such as patient survival time, tumor size, Ki67, pathologic stage, N stage, estrogen receptor (ER) and progesterone receptor (PR) levels, correlated well with TSP50/p-AKT/ALDH1 expression status.

CONCLUSION

The effects of TSP50 on EMT and CSC-like properties promotion were verified to be dependent on PI3K p110α. Together, our study revealed a novel mechanism by which TSP50 facilitates the progression of breast cancer, which can provide new insights into TSP50-based breast cancer treatment strategies.

Disulfidptosis: A Novel Prognostic Criterion and Potential Treatment Strategy for Diffuse Large B-Cell Lymphoma (DLBCL)

Diffuse Large B-cell Lymphoma (DLBCL), with its intrinsic genetic and epigenetic heterogeneity, exhibits significantly variable clinical outcomes among patients treated with the current standard regimen. Disulfidptosis, a novel form of regulatory cell death triggered by disulfide stress, is characterized by the collapse of cytoskeleton proteins and F-actin due to intracellular accumulation of disulfides. We investigated the expression variations of disulfidptosis-related genes (DRGs) in DLBCL using two publicly available gene expression datasets. The initial analysis of DRGs in DLBCL (GSE12453) revealed differences in gene expression patterns between various normal B cells and DLBCL. Subsequent analysis (GSE31312) identified DRGs strongly associated with prognostic outcomes, revealing eight characteristic DRGs (CAPZB, DSTN, GYS1, IQGAP1, MYH9, NDUFA11, NDUFS1, OXSM). Based on these DRGs, DLBCL patients were stratified into three groups, indicating that (1) DRGs can predict prognosis, and (2) DRGs can help identify novel therapeutic candidates. This study underscores the significant role of DRGs in various biological processes within DLBCL. Assessing the risk scores of individual DRGs allows for more precise stratification of prognosis and treatment strategies for DLBCL patients, thereby enhancing the effectiveness of clinical practice.

Mechanisms Underlying the Rarity of Skeletal Muscle Cancers

Skeletal muscle (SKM), despite comprising ~40% of body mass, rarely manifests cancer. This review explores the mechanisms that help to explain this rarity, including unique SKM architecture and function, which prohibits the development of new cancer as well as negates potential metastasis to SKM. SKM also presents a unique immune environment that may magnify the anti-tumorigenic effect. Moreover, the SKM microenvironment manifests characteristics such as decreased extracellular matrix stiffness and altered lactic acid, pH, and oxygen levels that may interfere with tumor development. SKM also secretes anti-tumorigenic myokines and other molecules. Collectively, these mechanisms help account for the rarity of SKM cancer.

The epithelial adherens junction component PLEKHA7 regulates ECM remodeling and cell behavior through miRNA-mediated regulation of MMP1 and LOX

Epithelial adherens junctions (AJs) are cell-cell adhesion complexes that are influenced by tissue mechanics, such as those emanating from the extracellular matrix (ECM). Here, we introduce a mechanism whereby epithelial AJs can also regulate the ECM. We show that the AJ component PLEKHA7 regulates levels and activity of the key ECM remodeling components MMP1 and LOX in well-differentiated colon epithelial cells, through the miR-24 and miR-30c miRNAs. PLEKHA7 depletion in epithelial cells results in LOX-dependent ECM remodeling in culture and in the colonic mucosal lamina propria in mice. Furthermore, PLEKHA7-depleted cells exhibit increased migration and invasion rates that are MMP1- and LOX- dependent, and form colonies in 3D cultures that are larger in size and acquire aberrant morphologies in stiffer matrices. These results reveal an AJ-mediated mechanism, through which epithelial cells drive ECM remodeling to modulate their behavior, including acquisition of phenotypes that are hallmarks of conditions such as fibrosis and tumorigenesis.

Antitumor mechanisms and future clinical applications of the natural product triptolide

Triptolide (TPL) is a compound sourced from Tripterygium wilfordii Hook. F., a traditional Chinese medicinal herb recognized for its impressive anti-inflammatory, anti-angiogenic, immunosuppressive, and antitumor qualities. Notwithstanding its favorable attributes, the precise mechanism through which TPL influences tumor cells remains enigmatic. Its toxicity and limited water solubility significantly impede the clinical application of TPL. We offer a comprehensive overview of recent research endeavors aimed at unraveling the antitumor mechanism of TPL in this review. Additionally, we briefly discuss current strategies to effectively manage the challenges associated with TPL in future clinical applications. By compiling this information, we aim to enhance the understanding of the underlying mechanisms involved in TPL and identify potential avenues for further advancement in antitumor therapy.

Vitamin A Status Modulates Epithelial Mesenchymal Transition in the Lung: The Role of Furin

Vitamin A deficiency (VAD) induced TGF-β hyperactivation and reduced expression of cell adhesion proteins in the lung, suggesting that the disruption of retinoic acid (RA) signaling leads to epithelial-mesenchymal transition (EMT). To elucidate the role of lung vitamin A status in EMT, several EMT markers and the expression of the proprotein convertase furin, which activates TGF-β, were analyzed in two experimental models. Our in vivo model included control rats, VAD rats, and both control rats and VAD rats, treated with RA. For the in vitro studies, human bronchoalveolar epithelial cells treated with RA were used. Our data show that EMT and furin are induced in VAD rats. Furthermore, furin expression continues to increase much more markedly after treatment of VAD rats with RA. In control rats and cell lines, an acute RA treatment induced a significant increase in furin expression, concomitant with changes in EMT markers. A ChIP assay demonstrated that RA directly regulates furin transcription. These results emphasize the importance of maintaining vitamin A levels within the physiological range since both levels below and above this range can cause adverse effects that, paradoxically, could be similar. The role of furin in EMT is discussed.

RHOAL57V drives the development of diffuse gastric cancer through IGF1R-PAK1-YAP1 signaling

Cancer-associated mutations in the guanosine triphosphatase (GTPase) RHOA are found at different locations from the mutational hotspots in the structurally and biochemically related RAS. Tyr42-to-Cys (Y42C) and Leu57-to-Val (L57V) substitutions are the two most prevalent RHOA mutations in diffuse gastric cancer (DGC). RHOAY42C exhibits a gain-of-function phenotype and is an oncogenic driver in DGC. Here, we determined how RHOAL57V promotes DGC growth. In mouse gastric organoids with deletion of Cdh1, which encodes the cell adhesion protein E-cadherin, the expression of RHOAL57V, but not of wild-type RHOA, induced an abnormal morphology similar to that of patient-derived DGC organoids. RHOAL57V also exhibited a gain-of-function phenotype and promoted F-actin stress fiber formation and cell migration. RHOAL57V retained interaction with effectors but exhibited impaired RHOA-intrinsic and GAP-catalyzed GTP hydrolysis, which favored formation of the active GTP-bound state. Introduction of missense mutations at KRAS residues analogous to Tyr42 and Leu57 in RHOA did not activate KRAS oncogenic potential, indicating distinct functional effects in otherwise highly related GTPases. Both RHOA mutants stimulated the transcriptional co-activator YAP1 through actin dynamics to promote DGC progression; however, RHOAL57V additionally did so by activating the kinases IGF1R and PAK1, distinct from the FAK-mediated mechanism induced by RHOAY42C. Our results reveal that RHOAL57V and RHOAY42C drive the development of DGC through distinct biochemical and signaling mechanisms.

Changes in adhesion molecules: β-catenin, E-cadherin and Galectin-3 in cells of testicular seminoma

Introduction

The most common testicular tumors are seminomas. They are characterized by rapid growth and a very high potential for metastasis to other organs. Mutual interactions of tumor cells play an important role in the invasiveness and metastatic capacity, in which complexes of adhesion proteins play a special role. There is a lack of studies on changes in these molecules and their behaviour in testicular cancer. The aim of the study was immunohistochemical identification and evalutaion of adhesive molecules β-catenin, E-cadherin, galectin-3 in testicular cancer - seminoma.

Methods

Tests were performed on sections of testicular cancer - seminoma in comparison with unchanged tissue samples as a control. Material was taken from 30 patients who underwent orchiectomy. Immunohistochemistry and PCR were used to identify β-catenin, E-cadherin and galectin-3 and gene expression.

Results

Immunoreactivity and expression of β-catenin and E-cadherin in seminomas were markedly decreased compared to non-cancerous testicular tissue. Galectin-3 immunoreactivity was found in both control and cancerous tissue, but in different location. In non-cancerous tissue, it was localized in the cytoplasm of the cells of the seminiferous tubules, in seminomas it was localized mainly in the endothelium. The expression of the Lgals3 gene encoding galectin-3 in seminomas was slightl higher in relation to the tissue unchanged by the carcinogenetic process.

Conclusions

The results of the study suggest a significant role of β-catenin, E-cadherin and galectin-3 in the carcinogenesis of seminomas and may indicate new aspects of the patomechanism of seminomas formation, and thus time lead to better understand the biology of these tumors.

Actin-dependent recruitment of AGO2 to the zonula adherens

Adherens junctions are cadherin-based structures critical for cellular architecture. E-cadherin junctions in mature epithelial cell monolayers tether to an apical actomyosin ring to form the zonula adherens (ZA). We have previously shown that the adherens junction protein PLEKHA7 associates with and regulates the function of the core RNA interference (RNAi) component AGO2 specifically at the ZA. However, the mechanism mediating AGO2 recruitment to the ZA remained unexplored. Here, we reveal that this ZA-specific recruitment of AGO2 depends on both the structural and tensile integrity of the actomyosin cytoskeleton. We found that depletion of not only PLEKHA7, but also either of the three PLEKHA7-interacting, LIM-domain family proteins, namely LMO7, LIMCH1, and PDLIM1, results in disruption of actomyosin organization and tension, as well as disruption of AGO2 junctional localization and of its miRNA-binding ability. We also show that AGO2 binds Myosin IIB and that PLEKHA7, LMO7, LIMCH1, and PDLIM1 all disrupt interaction of AGO2 with Myosin IIB at the ZA. These results demonstrate that recruitment of AGO2 to the ZA is sensitive to actomyosin perturbations, introducing the concept of mechanosensitive RNAi machinery, with potential implications in tissue remodeling and in disease.

Alteration of Cadherin 3 Expression and DNA Methylation in Association with Aggressive Renal Cell Carcinoma

Cadherins (calcium-dependent adhesion proteins) are important in cellular adhesion and may play a role in the development and progression of renal cell carcinoma (RCC). This study investigated changes in cadherin 3 (CDH3; P-cadherin) mRNA expression, DNA methylation, and protein expression in RCC and compared the results with the histopathological and clinical characteristics of patients. The possible contribution of CDH3 to tumor cell invasiveness was tested in a functional assay using siRNA-based suppression of CDH3 expression and subsequent real-time impedance analysis using a Matrigel invasion model. Our analyses revealed a tumor-specific loss of CDH3 mRNA expression, CDH3 DNA hypermethylation, and loss of distal tubular and collecting duct CDH3 protein expression in RCC. A relatively higher methylation level in tumors was associated with a loss of cell differentiation and higher clinical stage. siRNA-induced suppression of CDH3 expression modulated the invasion characteristics of tumor cells in the impedance-based real-time cellular analysis. Our results indicate that loss of CDH3 expression is common in RCC and may contribute to the pathogenesis of a subset of RCC. Further studies to reveal the mechanisms of loss of expression and its effects on the invasive behavior of renal tumor cells are required.

Resveratrol exhibits diverse anti-cancer activities through epigenetic regulation of E-cadherin and p21 in triple-negative breast cancer cells

BACKGROUND

Triple-negative breast cancer (TNBC) has an aggressive phenotype and poor outcome, however no specific targeted therapy has been established for TNBC lacking germline BRCA1/2 pathogenic variants. To develop a novel therapeutic strategy, we explored the potential of resveratrol (RSV) for TNBC treatment.

METHODS

We investigated the effects of RSV on malignant phenotypes of TNBC cells as well as on apoptosis induced by ABT263, a specific inhibitor of BCL-2 and BCL-xL, using morphological observation, migration assay, β-galactosidase staining, and Hoechst staining. To elucidate the underlying mechanisms of RSV-mediated effects, expression levels and histone acetylation levels of cadherin 1 (CDH1, E-cadherin) and cyclin dependent kinase inhibitor 1A (CDKN1A, p21) were determined by RT-qPCR, western blotting, and chromatin immunoprecipitation. Furthermore, knockdown analysis was conducted to evaluate the involvement of E-cadherin and/or p21 in RSV potentiation on cytotoxic activity of ABT263.

RESULTS

RSV treatment induced epithelial-like cellular morphology and suppressed the migration capacity in MDA-MB-231 and BT-549-Luc TNBC cells. β-galactosidase-positive cells were increased after RSV treatment, indicating the induction of cellular senescence, in MDA-MB-231 cells but not in BT-549-Luc cells. RSV increased the expression and histone acetylation of CDH1 and CDKN1A in both cells. Interestingly, pre-treatment with RSV enhanced the induction of apoptosis in the ABT263-treated MDA-MB-231 and BT-549-Luc cells, and knockdown of CDKN1A decreased ABT263-induced apoptosis in RSV-treated MDA-MB-231 cells.

CONCLUSIONS

RSV represses the metastatic capacity and enhances the cytotoxic activity of ABT263 in TNBC cells. Our results suggested that RSV can potentially be used as a repressor of metastasis or a sensitizer to ABT263 for TNBC treatment via up-regulation of CDH1 and CDKN1A through epigenetic mechanisms.

Transición epitelio – mesenquima y cáncer

Cancer cell migration and invasion are critical components of metastatic disease, the leading cause of death in cancer patients. The epithe-lium-mesenchyme-transition (EMT) and mesenchyme-epithelium-transition (MET) are pathways involved in cancer metastasis. This process involves the degradation of cell-cell and cell-extracellular matrix junctions and the subse-quent loss of regulation of binding proteins such as E-cadherin. Cells undergo a reorganization of the cytoskeleton. These alterations are associated with a change in cell shape from epithelial to mesenchymal morphology. Understand-ing EMT and MET’s molecular and cellular basis provides fundamental insights into cancer etiology and may lead to new therapeutic strategies. In this review, we discuss some of the regulatory mechanisms and pathological role of epitheli-al-mesenchymal plasticity, focusing on the knowledge about the complexity and dynamics of this phenomenon in cancer

Artificial miRNAs derived from miR-181 family members have potential in cancer therapy due to an altered spectrum of target mRNAs

miRNAs are a class of noncoding RNAs with gene regulation properties, and they function as key factors in cell homeostasis. The interaction of miRNAs with their target mRNAs is largely considered to rely on sequence complementarity; however, some evidence indicates that mature miRNAs can adopt diverse conformations with implications for their function. Using the oncogenic miR-181 family as a study model, we suggest that a potential relationship between the primary sequence and secondary structure of miRNAs may have an impact on the number and spectrum of targeted cellular transcripts. We further emphasize that specific alterations in miR-181 primary sequences might impose certain constraints on target gene selection compared with the wild-type sequences, leading to the targeting of new transcripts with upregulated function in cancer.

MicroRNA-21 in gynecological cancers: From molecular pathogenesis to clinical significance

Ovarian, cervical, and endometrial cancers are the three most common gynecological cancer types (GCs). They hold a significant position as the leading causes of mortality among women with cancer-related death. However, GCs are often diagnosed late, severely limiting the efficacy of current treatment options. Thus, there is an urgent, unmet need for innovative experimentation to enhance the clinical treatment of GC patients. MicroRNAs (miRNAs) are a large and varied class of short noncoding RNAs (22 nucleotides in length) that have been shown to play essential roles in various biological processes involved in development. Recent research has shown that miR-211 influences tumorigenesis and cancer formation, adding to our knowledge of the miR-21 dysregulation in GCs. Furthermore, current research that sheds light on the crucial functions of miR-21 may provide supporting evidence for its potential prognostic, diagnostic, and therapeutic applications in the context of GCs. This review will thus focus on the most recent findings concerning miR-21 expression, miR-21 target genes, and the processes behind GCs. In addition, the latest findings that support miR-21's potential use as a non-invasive biomarker and therapeutic agent for detecting and treating cancer will be elucidated in this review. The roles played by various lncRNA/circRNA-miRNA-mRNA axis in GCs are also comprehensively summarized and described in this study, along with any possible implications for how these regulatory networks may contribute to the pathogenesis of GCs. Also, it is crucial to recognize the complexity of the processes involved in tumour therapeutic resistance as a significant obstacle in treating GCs. Furthermore, this review provides an overview of the current state of knowledge regarding the functional significance miR-21 in therapeutic resistance within the context of GCs.

YAP1 controls the N-cadherin-mediated tumor-stroma interaction in melanoma progression

Epithelial-to-mesenchymal transition (EMT) is crucial for melanoma cells to escape keratinocyte control, invade underlying dermal tissues, and metastasize to distant organs. The hallmark of EMT is the switch from epithelial cadherin (E-cadherin) to neural cadherin (N-cadherin), allowing melanoma cells to form a homotypic N-cadherin-mediated adhesion with stromal fibroblasts. However, how "cadherin switching" is initiated, maintained, and regulated in melanoma remains unknown. Here, we show that upon Yes-associated protein 1 (YAP1) ablation in cancer-associated fibroblasts (CAFs), the progression of a BRAF-mutant mouse melanoma was significantly suppressed in vivo, and overexpressing YAP1 in CAFs accelerated melanoma growth. CAFs require the YAP1 function to proliferate, migrate, remodel the cytoskeletal machinery and matrix, and promote cancer cell invasion. By RNA-Seq, N-cadherin was identified as a major downstream effector of YAP1 signaling in CAFs. YAP1 silencing led to N-cadherin downregulation in CAFs, which subsequently induced the downregulation of N-cadherin in neighboring melanoma cells. N-cadherin downregulation inhibited the PI3K-AKT signaling pathway in melanoma cells and suppressed melanoma growth in vivo, supporting the role of N-cadherin as an adhesive and signaling molecule in melanoma cells. This finding suggests that YAP1 depletion in CAFs induces the downregulation of p-AKT signaling in melanoma cells through the N-cadherin-mediated interaction between melanoma cells and CAFs. Importantly, our data underscore that CAFs can regulate N-cadherin-mediated interactions with melanoma cells. Thus, disentangling cadherin-mediated cell-cell interactions can potentially disrupt tumor-stroma interactions and reverse the tumor cell invasive phenotype.

Multi-omics analyses of glucose metabolic reprogramming in colorectal cancer

BACKGROUND

Glucose metabolic reprogramming (GMR) is a cardinal feature of carcinogenesis and metastasis. However, the underlying mechanisms have not been fully elucidated. The aim of this study was to profile the metabolic signature of primary tumor and circulating tumor cells from metastatic colorectal cancer (mCRC) patients using integrated omics analysis.

METHODS

PET-CT imaging, serum metabolomics, genomics and proteomics data of 325 high 18F-fluorinated deoxyglucose (FDGhigh) mCRC patients were analyzed. The para-tumor, primary tumor and liver metastatic tissues of mCRC patients were used for proteomics analysis.

RESULTS

The glucose uptake in tumor tissues as per the PET/CT images was correlated to serum levels of glutamic-pyruvic transaminase (ALT), total bilirubin (TBIL), creatinine (CRE). Proteomics analysis indicated that several differentially expressed proteins were enriched in both GMR and epithelial-mesenchymal transition (EMT)-related pathways. Using a tissue-optimized proteomic workflow, we identified novel proteomic markers (e.g. CCND1, EPCAM, RPS6), a novel PCK1-CDK6-INSR protein axis, and a potential role for FOLR (FR) in GMR/EMT of CRC cells. Finally, CEA/blood glucose (CSR) was defined as a new index, which can be used to jointly diagnose liver metastasis of colorectal cancer.

CONCLUSIONS

GMR in CRC cells is closely associated with the EMT pathway, and this network is a promising source of potential therapeutic targets.

Low-Temperature Plasma-Activated Medium Inhibits the Migration of Non-Small Cell Lung Cancer Cells via the Wnt/β-Catenin Pathway

This study explored the molecular mechanism of the plasma activation medium (PAM) inhibiting the migration ability of NSCLC (non-small cell lung cancer) cells. The effect of PAM incubation on the cell viability of NSCLC was detected through a cell viability experiment. Transwell cells and microfluidic chips were used to investigate the effects of PAM on the migration capacity of NSCLC cells, and the latter was used for the first time to observe the changes in the migration capacity of cancer cells treated with PAM. Moreover, the molecular mechanisms of PAM affecting the migration ability of NSCLC cells were investigated through intracellular and extracellular ROS detection, mitochondrial membrane potential, and Western blot experiments. The results showed that after long-term treatment with PAM, the high level of ROS produced by PAM reduced the level of the mitochondrial membrane potential of cells and blocked the cell division cycle in the G2/M phase. At the same time, the EMT process was reversed by inhibiting the Wnt/β-catenin signaling pathway. These results suggested that the high ROS levels generated by the PAM treatment reversed the EMT process by inhibiting the WNT/β-catenin pathway in NSCLC cells and thus inhibited the migration of NSCLC cells. Therefore, these results provide good theoretical support for the clinical treatment of NSCLC with PAM.

Novel signatures of prostate cancer progression and therapeutic resistance

INTRODUCTION

The extensive heterogeneity of prostate cancer (PCa) and multilayered complexity of progression to castration-resistant prostate cancer (CRPC) have contributed to the challenges of accurately monitoring advanced disease. Profiling of the tumor microenvironment with large-scale transcriptomic studies have identified gene signatures that predict biochemical recurrence, lymph node invasion, metastases, and development of therapeutic resistance through critical determinants driving CRPC.

AREAS COVERED

This review encompasses understanding of the role of different molecular determinants of PCa progression to lethal disease including the phenotypic dynamic of cell plasticity, EMT-MET interconversion, and signaling-pathways driving PCa cells to advance and metastasize. The value of liquid biopsies encompassing circulating tumor cells and extracellular vesicles to detect disease progression and emergence of therapeutic resistance in patients progressing to lethal disease is discussed. Relevant literature was added from PubMed portal.

EXPERT OPINION

Despite progress in the tumor-targeted therapeutics and biomarker discovery, distant metastasis and therapeutic resistance remain the major cause of mortality in patients with advanced CRPC. No single signature can encompass the tremendous phenotypic and genomic heterogeneity of PCa, but rather multi-threaded omics-derived and phenotypic markers tailored and validated into a multimodal signature.

Critical roles of adherens junctions in diseases of the oral mucosa

The oral cavity is directly exposed to a variety of environmental stimuli and contains a diverse microbiome that continuously interacts with the oral epithelium. Therefore, establishment and maintenance of the barrier function of the oral mucosa is of paramount importance for its function and for the body's overall health. The adherens junction is a cell-cell adhesion complex that is essential for epithelial barrier function. Although a considerable body of work has associated barrier disruption with oral diseases, the molecular underpinnings of these associations have not been equally investigated. This is critical, since adherens junction components also possess significant signaling roles in the cell, in addition to their architectural ones. Here, we summarize current knowledge involving adherens junction components in oral pathologies, such as cancer and oral pathogen-related diseases, while we also discuss gaps in the knowledge and opportunities for future investigation of the relationship between adherens junctions and oral diseases.

Arsenic impairs stem cell differentiation via the Hippo signaling pathway

Arsenic is a ubiquitous toxic metalloid, with over 150 million people exposed to arsenic concentrations above the current 10 ppb drinking water standard through contaminated food and water. Arsenic is a known developmental toxicant as neuronal and muscle development are disrupted following arsenic exposure during embryogenesis. In this study, murine embryonic stem cells were chronically exposed to 0.1 μM (7.5 ppb) arsenic for 32 weeks. RNA sequencing showed that the Hippo signaling pathway, which is involved in embryonic development and pluripotency maintenance, is impaired following arsenic exposure. Thus, temporal changes in the Hippo pathway's core components and its downstream target genes Ctgf and c-Myc were investigated. Protein expression of the pathway's main effector YAP in its active form was significantly upregulated by 3.7-fold in arsenic-exposed cells at week 8, while protein expression of inactive phosphorylated YAP was significantly downregulated by 2.5- and 2-fold at weeks 8 and 16. Exposure to arsenic significantly increased the ratio between nuclear and cytoplasmic YAP by 1.9-fold at weeks 16 and 28. The ratio between nuclear and cytoplasmic transcriptional enhancer factor domain was similarly increased in arsenic-treated samples by 3.4- and 1.6-fold at weeks 16 and 28, respectively. Levels of Ctgf and c-Myc were also upregulated following arsenic exposure. These results suggest that chronic exposure to an environmentally relevant arsenic concentration might hinder cellular differentiation and maintain pluripotency through the impairment of the Hippo signaling pathway resulting in increased YAP activation.

Physicochemical Principles of Adhesion Mechanisms in the Brain

The brain functions through neuronal circuits and networks that are synaptically connected. This type of connection can exist due to physical forces that interact to stabilize local contacts in the brain. Adhesion is a fundamental physical phenomenon that allows different layers, phases, and tissues to connect. Similarly, synaptic connections are stabilized by specialized adhesion proteins. This review discusses the basic physical and chemical properties of adhesion. Cell adhesion molecules (CAMs) such as cadherins, integrins, selectins, and immunoglobulin family of cell adhesion molecules (IgSF) will be discussed, and their role in physiological and pathological brain function. Finally, the role of CAMs at the synapse will be described. In addition, methods for studying adhesion in the brain will be presented.

YAP-regulated type II alveolar epithelial cell differentiation mediated by human umbilical cord-derived mesenchymal stem cells in acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) contributes to higher mortality worldwide. Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have immunomodulatory and regenerative potential. However, the effects of hUC-MSCs as an ARDS treatment remain unclear. We investigated the role of hUC-MSCs in the differentiation of type II alveolar epithelial cells (AECII) by regulating Yes-associated protein (YAP) in ARDS. Male C57BL/6JNarl mice were intratracheally (i.t.) administered lipopolysaccharide (LPS) to induce an ARDS model, followed by a single intravenous (i.v.) dose of hUC-MSCs. hUC-MSCs improved pulmonary function, decreased inflammation on day 3, and mitigated lung injury by reducing the lung injury score and increasing lung aeration (%) in mice on day 7 (p < 0.05). hUC-MSCs inactivated YAP on AECII and facilitated cell differentiation by decreasing Pro-surfactant protein C (Pro-SPC) and galectin 3 (LGALS3) while increasing podoplanin (T1α) in lungs of mice (p < 0.05). In AECII MLE-12 cells, both coculture with hUC-MSCs after LPS exposure and the YAP inhibitor, verteporfin, reduced Pro-SPC and LGALS3, whereas the YAP inhibitor increased T1α expression (p < 0.05). In conclusion, hUC-MSCs ameliorated lung injury of ARDS and regulated YAP to facilitate AECII differentiation.

The aryl sulfonamide indisulam inhibits gastric cancer cell migration by promoting the ubiquitination and degradation of the transcription factor ZEB1

Gastric cancer is one of the cancers with high morbidity and mortality worldwide. The aryl sulfonamide indisulam inhibits the proliferation of several types of cancer cells through its function as a molecular glue to promote the ubiquitination and degradation of RNA-binding motif protein 39 (RBM39). However, it is unknown whether and how indisulam regulates the migration of cancer cells. In this work, using label-free quantitative proteomics, we discover that indisulam significantly attenuates N-cadherin, a marker for epithelial to mesenchymal transition and migration of cancer cells. Our bioinformatics analysis and biochemical experiments reveal that indisulam promotes the interaction between the zinc finger E-box-binding homeobox 1 (ZEB1), a transcription factor of N-cadherin, and DCAF15, a substrate receptor of CRL4 E3 ubiquitin ligase, and enhances ZEB1 ubiquitination and proteasomal degradation. In addition, our cell line-based experiments demonstrate that indisulam inhibits the migration of gastric cancer cells in a ZEB1-dependent manner. Analyses of patient samples and datasets in public databases reveal that tumor tissues from patients with gastric cancer express high ZEB1 mRNA and this high expression reduces patient survival rate. Finally, we show that treatment of gastric tumor samples with indisulam significantly reduces ZEB1 protein levels. Therefore, this work discloses a new mechanism by which indisulam inhibits the migration of gastric cancer cells, indicating that indisulam exhibits different biological functions through distinct signaling molecules.

Association of Kaiso and partner proteins in oral squamous cell carcinoma

Objectives

1. Identification of protein expression and subcellular localization of E-cadherin (E-cad), p120 catenin (P120ctn), and Kaiso in oral cancer (OC). 2. To study the protein expression of cyclin D1 and c-Myc (Kaiso targets) and determine their relationship with the expression and localization of Kaiso.

Methods

Histological grading was performed in accordance with Broder's criteria. Expression and localization data for E-cad, p120ctn, Kaiso, cyclin D1, and c-Myc were acquired using immunohistochemistry. Data were analyzed using SPSS version 21. The chi-square test was used to measure the statistical significance of associations, with p < 0.05 as statistically significant.

Results

Of 47 OC cases, 36% showed low E-cad expression and 34% showed low p120ctn. Low Kaiso expression was recognized in 78% of tumor specimens. Aberrant cytoplasmic localization of p120ctn was seen in 80.8% cases. Cytoplasmic Kaiso localization was appreciated in 87% of tumor tissues, whereas 29.7% lacked any nuclear Kaiso. Kaiso expression was significantly associated with the expression of cyclin D1 but not with c-Myc.

Conclusion

The present study identified a change in the localization of Kaiso in OC. The significance of this in relation to OC and tumor prognosis needs to be investigated with further studies using larger sample sizes and more sensitive molecular tools.

ECM Substrates Impact RNAi Localization at Adherens Junctions of Colon Epithelial Cells

The extracellular matrix (ECM) plays crucial roles in tissue homeostasis. Abnormalities in ECM composition are associated with pathological conditions, such as fibrosis and cancer. These ECM alterations are sensed by the epithelium and can influence its behavior through crosstalk with other mechanosensitive complexes, including the adherens junctions (AJs). We have previously shown that the AJs, through their component PLEKHA7, recruit the RNAi machinery to regulate miRNA levels and function. We have particularly shown that the junctional localization of RNAi components is critical for their function. Here, we investigated whether different ECM substrates can influence the junctional localization of RNAi complexes. To do this, we plated colon epithelial Caco2 cells on four key ECM substrates found in the colon under normal or pathogenic conditions, namely laminin, fibronectin, collagen I, and collagen IV, and we examined the subcellular distribution of PLEKHA7, and of the key RNAi components AGO2 and DROSHA. Fibronectin and collagen I negatively impacted the junctional localization of PLEKHA7, AGO2, and DROSHA when compared to laminin. Furthermore, fibronectin, collagen I, and collagen IV disrupted interactions of AGO2 and DROSHA with their essential partners GW182 and DGCR8, respectively, both at AJs and throughout the cell. Combinations of all substrates with fibronectin also negatively impacted junctional localization of PLEKHA7 and AGO2. Additionally, collagen I triggered accumulation of DROSHA at tri-cellular junctions, while both collagen I and collagen IV resulted in DROSHA accumulation at basal areas of cell-cell contact. Altogether, fibronectin and collagens I and IV, which are elevated in the stroma of fibrotic and cancerous tissues, altered localization patterns and disrupted complex formation of PLEKHA7 and RNAi components. Combined with our prior studies showing that apical junctional localization of the PLEKHA7-RNAi complex is critical for regulating tumor-suppressing miRNAs, this work points to a yet unstudied mechanism that could contribute to epithelial cell transformation.

Cell Adhesion Molecules Affected by Ionizing Radiation and Estrogen in an Experimental Breast Cancer Model

Cancer develops in a multi-step process where environmental carcinogenic exposure is a primary etiological component, and where cell-cell communication governs the biological activities of tissues. Identifying the molecular genes that regulate this process is essential to targeting metastatic breast cancer. Ionizing radiation can modify and damage DNA, RNA, and cell membrane components such as lipids and proteins by direct ionization. Comparing differential gene expression can help to determine the effect of radiation and estrogens on cell adhesion. An in vitro experimental breast cancer model was developed by exposure of the immortalized human breast epithelial cell line MCF-10F to low doses of high linear energy transfer α particle radiation and subsequent growth in the presence of 17β-estradiol. The MCF-10F cell line was analyzed in different stages of transformation that showed gradual phenotypic changes including altered morphology, increase in cell proliferation relative to the control, anchorage-independent growth, and invasive capability before becoming tumorigenic in nude mice. This model was used to determine genes associated with cell adhesion and communication such as E-cadherin, the desmocollin 3, the gap junction protein alpha 1, the Integrin alpha 6, the Integrin beta 6, the Keratin 14, Keratin 16, Keratin 17, Keratin 6B, and the laminin beta 3. Results indicated that most genes had greater expression in the tumorigenic cell line Tumor2 derived from the athymic animal than the Alpha3, a non-tumorigenic cell line exposed only to radiation, indicating that altered expression levels of adhesion molecules depended on estrogen. There is a significant need for experimental model systems that facilitate the study of cell plasticity to assess the importance of estrogens in modulating the biology of cancer cells.

Adhesion strength between cells regulate nonmonotonic growth by a biomechanical feedback mechanism

We determine how intercellular interactions and mechanical pressure experienced by single cells regulate cell proliferation using a minimal computational model for three-dimensional multicellular spheroid (MCS) growth. We discover that emergent spatial variations in the cell division rate, depending on the location of the cells either at the core or periphery within the MCS, is regulated by intercellular adhesion strength (fad). Varying fad results in nonmonotonic proliferation of cells in the MCS. A biomechanical feedback mechanism coupling the fad and microenvironment-dependent pressure fluctuations relative to a threshold value (pc) determines the onset of a dormant phase, and explains the nonmonotonic proliferation response. Increasing fad from low values enhances cell proliferation because pressure on individual cells is smaller compared with pc. However, at high fad, cells readily become dormant and cannot rearrange effectively in spacetime, leading to arrested cell proliferation. Utilizing our theoretical predictions, we explain experimental data on the impact of adhesion strength on cell proliferation and find good agreement. Our work, which shows that proliferation is regulated by pressure-adhesion feedback mechanism, may be a general feature of multicellular growth.

Hereditary Diffuse Gastric Cancer: Molecular Genetics, Biological Mechanisms and Current Therapeutic Approaches

Hereditary diffuse gastric cancer is an autosomal dominant syndrome characterized by a high prevalence of diffuse gastric cancer and lobular breast cancer. It is caused by inactivating mutations in the tumor suppressor gene CDH1. Genetic testing technologies have become more efficient over the years, also enabling the discovery of other susceptibility genes for gastric cancer, such as CTNNA1 among the most important genes. The diagnosis of pathogenic variant carriers with an increased risk of developing gastric cancer is a selection process involving a multidisciplinary team. To achieve optimal long-term results, it requires shared decision-making in risk management. In this review, we present a synopsis of the molecular changes and current therapeutic approaches in HDGC based on the current literature.

N-Cadherin Distinguishes Intrahepatic Cholangiocarcinoma from Liver Metastases of Ductal Adenocarcinoma of the Pancreas

Carcinomas of the pancreatobiliary system confer an especially unfavorable prognosis. The differential diagnosis of intrahepatic cholangiocarcinoma (iCCA) and its subtypes versus liver metastasis of ductal adenocarcinoma of the pancreas (PDAC) is clinically important to allow the best possible therapy. We could previously show that E-cadherin and N-cadherin, transmembrane glycoproteins of adherens junctions, are characteristic features of hepatocytes and cholangiocytes. We therefore analyzed E-cadherin and N-cadherin in the embryonally related epithelia of the bile duct and pancreas, as well as in 312 iCCAs, 513 carcinomas of the extrahepatic bile ducts, 228 gallbladder carcinomas, 131 PDACs, and precursor lesions, with immunohistochemistry combined with image analysis, fluorescence microscopy, and immunoblots. In the physiological liver, N-cadherin colocalizes with E-cadherin in small intrahepatic bile ducts, whereas larger bile ducts and pancreatic ducts are positive for E-cadherin but contain decreasing amounts of N-cadherin. N-cadherin was highly expressed in most iCCAs, whereas in PDACs, N-cadherin was negative or only faintly expressed. E- and N-cadherin expression in tumors of the pancreaticobiliary tract recapitulate their expression in their normal tissue counterparts. N-cadherin is a helpful marker for the differential diagnosis between iCCA and PDAC, with a specificity of 96% and a sensitivity of 67% for small duct iCCAs and 50% for large duct iCCAs.

Molecular Mechanisms and Potential Rationale of Immunotherapy in Peritoneal Metastasis of Advanced Gastric Cancer

Peritoneal metastasis (PM) is one of the most frequent metastasis patterns of gastric cancer (GC), and the prognosis of patients with PM is very dismal. According to Paget’s theory, disseminated free cancer cells are seeded and survive in the abdominal cavity, adhere to the peritoneum, invade the subperitoneal tissue, and proliferate through angiogenesis. In these sequential processes, several key molecules are involved. From a therapeutic point of view, immunotherapy with chemotherapy combination has become the standard of care for advanced GC. Several clinical trials of newer immunotherapy agents are ongoing. Understanding of the molecular process of PM and the potential rationale of immunotherapy for PM treatment is necessary. Beyond understanding of the molecular aspect of PM, many studies have been conducted on the modality of treatment of PM. Notably, intraperitoneal approaches, including chemotherapy or immunotherapy, have been conducted, because systemic treatment of PM has limitations. In this study, we reviewed the molecular mechanisms and immunologic aspects of PM, and intraperitoneal approaches under investigation for treating PM.

miRNAs Copy Number Variations Repertoire as Hallmark Indicator of Cancer Species Predisposition

Aging is one of the hallmarks of multiple human diseases, including cancer. We hypothesized that variations in the number of copies (CNVs) of specific genes may protect some long-living organisms theoretically more susceptible to tumorigenesis from the onset of cancer. Based on the statistical comparison of gene copy numbers within the genomes of both cancer-prone and -resistant species, we identified novel gene targets linked to tumor predisposition, such as CD52, SAT1 and SUMO. Moreover, considering their genome-wide copy number landscape, we discovered that microRNAs (miRNAs) are among the most significant gene families enriched for cancer progression and predisposition. Through bioinformatics analyses, we identified several alterations in miRNAs copy number patterns, involving miR-221, miR-222, miR-21, miR-372, miR-30b, miR-30d and miR-31, among others. Therefore, our analyses provide the first evidence that an altered miRNAs copy number signature can statistically discriminate species more susceptible to cancer from those that are tumor resistant, paving the way for further investigations.

Circular RNA 0001666 inhibits colorectal cancer cell proliferation, invasion and stemness by inactivating the Wnt/β-catenin signaling pathway and targeting microRNA-1229

A previous bioinformatics study suggested that circular RNA 0001666 (circ_0001666) and its target microRNA (miR)-1229 were associated with colorectal cancer (CRC) pathogenesis. However, the role of this interaction in the regulation of CRC cell malignancy remains unclear. Thus, the aim of the present study was to examine the interaction between circ_0001666 and miR-1229, and its effects on CRC cell malignancy. circ_0001666 overexpression or knockdown plasmids were transfected into the HT-29 and HCT-116 cell lines. In addition, in rescue experiments, circ_000166 or miR-1229 overexpression plasmids were transfected into the HT-29 cell line, either alone or in combination. Following transfection, cell proliferation, apoptosis, invasion and the number of CD133+ cells were analyzed. The protein expression level of proteins in the Wnt/β-catenin pathway was also examined. In both HT-29 and HCT-116 cell lines, circ_0001666 overexpression increased apoptosis, whilst inhibiting cell proliferation and invasion, and reducing the frequency of CD133+ cells. By contrast, circ_0001666 knockdown reduced apoptosis, but increased cell proliferation and the number of CD133+ cells. However, cell invasion remained unaffected. In addition, circ_0001666 expression levels negatively regulated those of miR-1229, whereas miR-1229 expression did not affect circ_0001666, in both the HT-29 and HCT-116 cell lines. Furthermore, a luciferase reporter assay confirmed that miR-1229 directly bound to circ_0001666. In the HT-29 cell line, miR-1229 overexpression activated the Wnt/β-catenin pathway, and promoted cell proliferation, invasion and stemness, while suppressing cell apoptosis. In addition, miR-1229 overexpression reversed the effects of circ_0001666 overexpression. In conclusion, circ_0001666 suppresses CRC cell proliferation, invasion and stemness by inhibiting the Wnt/β-catenin signaling pathway by targeting miR-1229, and may represent a potential target for CRC treatment.

P-Cadherin Regulates Intestinal Epithelial Cell Migration and Mucosal Repair, but Is Dispensable for Colitis Associated Colon Cancer

Recurrent chronic mucosal inflammation, a characteristic of inflammatory bowel diseases (IBD), perturbs the intestinal epithelial homeostasis resulting in formation of mucosal wounds and, in most severe cases, leads to colitis-associated colon cancer (CAC). The altered structure of epithelial cell-cell adhesions is a hallmark of intestinal inflammation contributing to epithelial injury, repair, and tumorigenesis. P-cadherin is an important adhesion protein, poorly expressed in normal intestinal epithelial cells (IEC) but upregulated in inflamed and injured mucosa. The goal of this study was to investigate the roles of P-cadherin in regulating intestinal inflammation and CAC. P-cadherin expression was markedly induced in the colonic epithelium of human IBD patients and CAC tissues. The roles of P-cadherin were investigated in P-cadherin null mice using dextran sulfate sodium (DSS)-induced colitis and an azoxymethane (AOM)/DSS induced CAC. Although P-cadherin knockout did not affect the severity of acute DSS colitis, P-cadherin null mice exhibited faster recovery after colitis. No significant differences in the number of colonic tumors were observed in P-cadherin null and control mice. Consistently, the CRISPR/Cas9-mediated knockout of P-cadherin in human IEC accelerated epithelial wound healing without affecting cell proliferation. The accelerated migration of P-cadherin depleted IEC was driven by activation of Src kinases, Rac1 GTPase and myosin II motors and was accompanied by transcriptional reprogramming of the cells. Our findings highlight P-cadherin as a negative regulator of IEC motility in vitro and mucosal repair in vivo. In contrast, this protein is dispensable for IEC proliferation and CAC development.

Is type 2 diabetes mellitus another intercellular junction-related disorder?

Type 2 diabetes mellitus (T2D) is nowadays a worldwide epidemic and has become a major challenge for health systems around the world. It is a multifactorial disorder, characterized by a chronic state of hyperglycemia caused by defects in the production as well as in the peripheral action of insulin. This minireview highlights the experimental and clinical evidence that supports the novel idea that intercellular junctions (IJs)-mediated cell-cell contacts play a role in the pathogenesis of T2D. It focuses on IJs repercussion for endocrine pancreas, intestinal barrier, and kidney dysfunctions that contribute to the onset and evolution of this metabolic disorder.

Remodelling of the tumour microenvironment by the kallikrein-related peptidases

Kallikrein-related peptidases (KLKs) are critical regulators of the tumour microenvironment. KLKs are proteolytic enzymes regulating multiple functions of bioactive molecules including hormones and growth factors, membrane receptors and the extracellular matrix architecture involved in cancer progression and metastasis. Perturbations of the proteolytic cascade generated by these peptidases, and their downstream signalling actions, underlie tumour emergence or blockade of tumour growth. Recent studies have also revealed their role in tumour immune suppression and resistance to cancer therapy. Here, we present an overview of the complex biology of the KLK family and its context-dependent nature in cancer, and discuss the different therapeutic strategies available to potentially target these proteases.

CDH3 is associated with a poor prognosis by promoting the malignance and chemoresistance in oral squamous cell carcinoma

BACKGROUND

CDH3 is recognized as an oncogene in various malignancies. Here, we aim to explore the association of CDH3 expression and prognostic implication in oral squamous cell carcinoma (OSCC).

METHODS

Bioinformatics was used to analyze differentially expressed genes in the TCGA database. The OSCC tissues of 136 cases were used for immunohistochemistry. Cox proportional hazard analysis was used to analyze the relationship between prognostic factors, CDH3 expression and patient survival. Kaplan-Meier analysis was adopted to calculate survival rates. RT-qPCR and Western blot were performed to detect the expression levels of CDH3 in oral squamous cell lines. The cell viability and colony formation abilities were examined by CCK-8 and colony formation assays, respectively. Wound healing assay was performed to examine the invasion ability of cells.

RESULTS

CDH3 is up-regulated in oral squamous cell carcinoma and related to bad prognosis. Knock-down of CDH3 limited cell viability, colony formation ability, migration, invasion and chemoresistance of OSCC cells.

CONCLUSION

CDH3 is associated with a poor prognosis through promoting migration, invasion and chemoresistance in oral squamous cell carcinoma.

Collective mechanical responses of cadherin-based adhesive junctions as predicted by simulations

Cadherin-based adherens junctions and desmosomes help stabilize cell-cell contacts with additional function in mechano-signaling, while clustered protocadherin junctions are responsible for directing neuronal circuits assembly. Structural models for adherens junctions formed by epithelial cadherin (CDH1) proteins indicate that their long, curved ectodomains arrange to form a periodic, two-dimensional lattice stabilized by tip-to-tip trans interactions (across junction) and lateral cis contacts. Less is known about the exact architecture of desmosomes, but desmoglein (DSG) and desmocollin (DSC) cadherin proteins are also thought to form ordered junctions. In contrast, clustered protocadherin (PCDH)-based cell-cell contacts in neuronal tissues are thought to be responsible for self-recognition and avoidance, and structural models for clustered PCDH junctions show a linear arrangement in which their long and straight ectodomains form antiparallel overlapped trans complexes. Here, we report all-atom molecular dynamics simulations testing the mechanics of minimalistic adhesive junctions formed by CDH1, DSG2 coupled to DSC1, and PCDHγB4, with systems encompassing up to 3.7 million atoms. Simulations generally predict a favored shearing pathway for the adherens junction model and a two-phased elastic response to tensile forces for the adhesive adherens junction and the desmosome models. Complexes within these junctions first unbend at low tensile force and then become stiff to unbind without unfolding. However, cis interactions in both the CDH1 and DSG2-DSC1 systems dictate varied mechanical responses of individual dimers within the junctions. Conversely, the clustered protocadherin PCDHγB4 junction lacks a distinct two-phased elastic response. Instead, applied tensile force strains trans interactions directly, as there is little unbending of monomers within the junction. Transient intermediates, influenced by new cis interactions, are observed after the main rupture event. We suggest that these collective, complex mechanical responses mediated by cis contacts facilitate distinct functions in robust cell-cell adhesion for classical cadherins and in self-avoidance signaling for clustered PCDHs.

Expression of N-Terminal-Deficient E-Cadherin Protein in Invasive Lobular Carcinoma of the Breast

Invasive lobular carcinoma (ILC) of the breast is characterized by the discohesive growth of tumor cells, which is mainly associated with the complete loss of E-cadherin (E-cad) expression. However, some aberrant expression patterns of E-cad protein that are inconsistent with their morphologies have been reported in ILC. We report herein ILC cases expressing a new type of abnormal E-cad protein that lacks the N-terminal domain, but conserves the C-terminal domain on the cell membrane. Immunohistochemical staining of 299 ILC cases using specific antibodies against the N-terminal or C-terminal region of E-cad revealed that 227 (76%) cases showed loss of the membranous expression of both terminuses (N-/C-) and 72 (24%) cases showed expression of only the C-terminus (N-/C+). In all cases, the expression of p120-catenin and β-catenin coincided with the expression of the C-terminus of E-cad. Clinicopathologic analysis revealed that N-/C+ expression in ILC cells was significantly associated with the histologic subtype (especially mixed-type ILC with another histologic type) and immunohistochemical molecular subtype (especially the triple-negative subtype), but not with prognostic factors (pT or pN). In addition, 12 of 15 cases (80%) with aberrant cytoplasmic localization of the N-terminal of E-cad showed diffuse membranous expression of the C-terminal domain. Additional immunohistochemistry using an antibody recognizing the extracellular juxtamembrane region showed that 28 (39%) of the N-/C+ cases had lost membranous expression, suggesting diversity in the deletion pattern of the N-terminal region. Our findings provide a novel mechanism for the loss of E-cad function because of N-terminal-deficient E-cad protein in ILC.

Proteolytic Landscapes in Gastric Pathology and Cancerogenesis

Gastric cancer is a leading cause of cancer-related death, and a large proportion of cases are inseparably linked to infections with the bacterial pathogen and type I carcinogen Helicobacter pylori. The development of gastric cancer follows a cascade of transformative tissue events in an inflammatory environment. Proteases of host origin as well as H. pylori-derived proteases contribute to disease progression at every stage, from chronic gastritis to gastric cancer. In the present article, we discuss the importance of (metallo-)proteases in colonization, epithelial inflammation, and barrier disruption in tissue transformation, deregulation of cell proliferation and cell death, as well as tumor metastasis and neoangiogenesis. Proteases of the matrix metalloproteinase (MMP) and a disintegrin and metalloproteinase domain-containing protein (ADAM) families, caspases, calpain, and the H. pylori proteases HtrA, Hp1012, and Hp0169 cleave substrates including extracellular matrix molecules, chemokines, and cytokines, as well as their cognate receptors, and thus shape the pathogenic microenvironment. This review aims to summarize the current understanding of how proteases contribute to disease progression in the gastric compartment.

Heterocellular N-cadherin junctions enable nontransformed cells to inhibit the growth of adjacent transformed cells

BACKGROUND

The Src tyrosine kinase phosphorylates effector proteins to induce expression of the podoplanin (PDPN) receptor in order to promote tumor progression. However, nontransformed cells can normalize the growth and morphology of neighboring transformed cells. Transformed cells must escape this process, called "contact normalization", to become invasive and malignant. Contact normalization requires junctional communication between transformed and nontransformed cells. However, specific junctions that mediate this process have not been defined. This study aimed to identify junctional proteins required for contact normalization.

METHODS

Src transformed cells and oral squamous cell carcinoma cells were cultured with nontransformed cells. Formation of heterocellular adherens junctions between transformed and nontransformed cells was visualized by fluorescent microscopy. CRISPR technology was used to produce cadherin deficient and cadherin competent nontransformed cells to determine the requirement for adherens junctions during contact normalization. Contact normalization of transformed cells cultured with cadherin deficient or cadherin competent nontransformed cells was analyzed by growth assays, immunofluorescence, western blotting, and RNA-seq. In addition, Src transformed cells expressing PDPN under a constitutively active exogenous promoter were used to examine the ability of PDPN to override contact normalization.

RESULTS

We found that N-cadherin (N-Cdh) appeared to mediate contact normalization. Cadherin competent cells that expressed N-Cdh inhibited the growth of neighboring transformed cells in culture, while cadherin deficient cells failed to inhibit the growth of these cells. Results from RNA-seq analysis indicate that about 10% of the transcripts affected by contact normalization relied on cadherin mediated communication, and this set of genes includes PDPN. In contrast, cadherin deficient cells failed to inhibit PDPN expression or normalize the growth of adjacent transformed cells. These data indicate that nontransformed cells formed heterocellular cadherin junctions to inhibit PDPN expression in adjacent transformed cells. Moreover, we found that PDPN enabled transformed cells to override the effects of contact normalization in the face of continued N-Cdh expression. Cadherin competent cells failed to normalize the growth of transformed cells expressing PDPN under a constitutively active exogenous promoter.

CONCLUSIONS

Nontransformed cells form cadherin junctions with adjacent transformed cells to decrease PDPN expression in order to inhibit tumor cell proliferation. Cancer begins when a single cell acquires changes that enables them to form tumors. During these beginning stages of cancer development, normal cells surround and directly contact the cancer cell to prevent tumor formation and inhibit cancer progression. This process is called contact normalization. Cancer cells must break free from contact normalization to progress into a malignant cancer. Contact normalization is a widespread and powerful process; however, not much is known about the mechanisms involved in this process. This work identifies proteins required to form contacts between normal cells and cancer cells, and explores pathways by which cancer cells override contact normalization to progress into malignant cancers. Video Abstract.