Molecule E-cadherin Research Articles

E-cadherin staining in the diagnosis of lobular versus ductal neoplasms of the breast: the emperor has no clothes.

Categorizing breast neoplasia as ductal or lobular is a daily exercise that relies on a combination of histologic and immunohistochemical tools. The historically robust link between loss of the E-cadherin molecule and lobular neoplasia has rendered staining for E-cadherin by immunohistochemistry a staple of this diagnostic process. Unfortunately, discordances between E-cadherin expression and histomorphology, and variations in E-cadherin staining patterns and intensities abound in clinical practice, but are often neglected in favour of a binary interpretation of the E-cadherin result. In this article, we highlight the complexities of E-cadherin expression through a review of the E-cadherin protein and its associated gene (CDH1), the mechanisms leading to aberrant/absent E-cadherin expression, and the implications of these factors on the reliability of the E-cadherin immunohistochemical stain in the classification of ductal versus lobular mammary neoplasia.

K-Ras(V12) differentially affects the three Akt isoforms in lung and pancreatic carcinoma cells and upregulates E-cadherin and NCAM via Akt3

K-Ras is the most frequently mutated Ras variant in pancreatic, colon and non-small cell lung adenocarcinoma. Activating mutations in K-Ras result in increased amounts of active Ras-GTP and subsequently a hyperactivation of effector proteins and downstream signaling pathways. Here, we demonstrate that oncogenic K-Ras(V12) regulates tumor cell migration by activating the phosphatidylinositol 3-kinases (PI3-K)/Akt pathway and induces the expression of E-cadherin and neural cell adhesion molecule (NCAM) by upregulation of Akt3. In vitro interaction and co-precipitation assays identified PI3-Kα as a bona fide effector of active K-Ras4B but not of H-Ras or N-Ras, resulting in enhanced Akt phosphorylation. Moreover, K-Ras(V12)-induced PI3-K/Akt activation enhanced migration in all analyzed cell lines. Interestingly, Western blot analyses with Akt isoform-specific antibodies as well as qPCR studies revealed, that the amount and the activity of Akt3 was markedly increased whereas the amount of Akt1 and Akt2 was downregulated in EGFP-K-Ras(V12)-expressing cell clones. To investigate the functional role of each Akt isoform and a possible crosstalk of the isoforms in more detail, each isoform was stably depleted in PANC-1 pancreatic and H23 lung carcinoma cells. Akt3, the least expressed Akt isoform in most cell lines, is especially upregulated and active in Akt2-depleted cells. Since expression of EGFP-K-Ras(V12) reduced E-cadherin-mediated cell-cell adhesion by induction of polysialylated NCAM, Akt3 was analyzed as regulator of E-cadherin and NCAM. Western blot analyses revealed pronounced reduction of E-cadherin and NCAM in the Akt3-kd cells, whereas Akt1 and Akt2 depletion upregulated E-cadherin, especially in H23 lung carcinoma cells. In summary, we identified oncogenic K-Ras4B as a key regulator of PI3-Kα-Akt signaling and Akt3 as a crucial regulator of K-Ras4B-induced modulation of E-cadherin and NCAM expression and localization.

Huddled and Preternatural- Atypical Lobular Hyperplasia

Atypical lobular hyperplasia manifests as a clonal proliferation of dis-cohesive epithelial cells emerging from terminal duct lobular units. Neoplasm appears reminiscent of lobular carcinoma in situ (LCIS) although cellular quantification is reduced. Characteristically, the incidentally discovered lesion is associated with dysfunction or decimation of E-cadherin. Additionally designated as lobular intraepithelial neoplastic 1 (LIN1), tumefaction exemplifies a female preponderance. Typically, adult subjects are implicated. Tumefaction is commonly encountered within the fifth decade although no age of disease emergence is exempt. Atypical lobular hyperplasia is detected within<1% of core needle biopsies adopted for evaluating BI-RADS 4 lesions [1,2]. Atypical lobular hyperplasia may incriminate bilateral breasts wherein specific lesion localization is absent. Tumefaction exhibits loss of chromosome 16qand deletion of CDH1 genes with loss of function of E-cadherin, a Tran’s membrane cell adhesion molecule. Alternatively, altered function of E-cadherin may occur. Exceptionally, various adhesion proteins are implicated wherein E-cadherin molecule appears stable [1,2]. Characteristically, atypical lobular hyperplasia is a diploid neoplasm. Tumefaction exhibits loss of heterozygosis (LOH) at chromosome 16q. A subset of neoplasms demonstrates methylation of CDH1 gene. Several tumefaction express loss of chromosome 22q and 16p, gain of chromosome 2p11.2, 5q32- 33.1 (CSF1R), 6q, 11q13 or 14q32.33.

Study on the Interactions Between Cisplatin and Cadherin by Fluorescence Spectrometry and Atomic Force Microscopy.

Cisplatin is an important platinum drug in cancer chemotherapy in clinical practice. It is well established that the main target of cisplatin is nuclear DNA. However, recent studies have demonstrated that platinum drugs may act on some important functional proteins in the human body. E-cadherin is a newly discovered glycoprotein that has been regarded as an important sign of the occurrence and development of some tumors. This study examines the interactions between cisplatin and E-cadherin by fluorescence spectrometry and atomic force microscopy (AFM). The fluorescence spectrometry results indicated that cisplatin can efficiently quench the fluorescence of E-cadherin. The calculated binding constant Kb was 3.20 × 106 (25 ℃), 1.36 × 106(31 ℃), and 8.22 × 105 L mol-1 (37 ℃). These results reveal that the fluorescence quenching effect of cisplatin on E-cadherin is static quenching. The obtained thermodynamic parameters ΔH < 0, ΔS < 0, and ΔG < 0, indicate that the binding of cisplatin on E-cadherin is a spontaneous process dominated by hydrogen bonds and Van der Waals forces. The AFM results revealed that E-cadherins are interlaced with each other to form a spherical-chain structure. The addition of cisplatin can significantly disrupt the interlaced structure of the E-cadherin molecules.

Zinc Finger Protein 90 Knockdown Promotes Cisplatin Sensitivity via Nrf2/HO-1 Pathway in Ovarian Cancer Cell.

Our study discussed the role of Zfp90 in ovarian cancer (OC) cell lines' sensitivity to cisplatin. We used two OC cell lines, SK-OV-3 and ES-2, to evaluate their role in cisplatin sensitization. The protein levels of p-Akt, ERK, caspase 3, Bcl-2, Bax, E-cadherin, MMP-2, MMP-9 and other drug resistance-related molecules, including Nrf2/HO-1, were discovered in the SK-OV-3 and ES-2 cells. We also used a human ovarian surface epithelial cell to compare the effect of Zfp90. Our outcomes indicated that cisplatin treatment generates reactive oxygen species (ROS) that modulate apoptotic protein expression. The anti-oxidative signal was also stimulated, which could hinder cell migration. The intervention of Zfp90 could greatly improve the apoptosis pathway and block the migrative pathway to regulate the cisplatin sensitivity in the OC cells. This study implies that the loss of function of Zfp90 might promote cisplatin sensitization in OC cells via regulating the Nrf2/HO-1 pathway to enhance cell apoptosis and inhibit the migrative effect in both SK-OV-3 and ES-2 cells.

Extracellular Vesicles Released from Cancer Cells Promote Tumorigenesis by Inducing Epithelial to Mesenchymal Transition via β-Catenin Signaling

Lung cancer is the leading cause of cancer-related deaths globally, in part due to a lack of early diagnostic tools and effective pharmacological interventions. Extracellular vesicles (EVs) are lipid-based membrane-bound particles released from all living cells in both physiological and pathological states. To understand the effects of lung-cancer-derived EVs on healthy cells, we isolated and characterized EVs derived from A549 lung adenocarcinoma cells and transferred them to healthy human bronchial epithelial cells (16HBe14o). We found that A549-derived EVs carry oncogenic proteins involved in the pathway of epithelial to mesenchymal transition (EMT) that are regulated by β-catenin. The exposure of 16HBe14o cells to A549-derived EVs resulted in a significant increase in cell proliferation, migration, and invasion via upregulating EMT markers such as E-Cadherin, Snail, and Vimentin and cell adhesion molecules such as CEACAM-5, ICAM-1, and VCAM-1, with concomitant downregulation of EpCAM. Our study suggests a role for cancer-cell-derived EVs to induce tumorigenesis in adjacent healthy cells by promoting EMT via β-catenin signaling.

E-cadherin is a biomarker for ferroptosis sensitivity in diffuse gastric cancer.

Gastric cancer is the third most common cause of cancer-related death worldwide. Diffuse-type gastric cancer (DGC) is a particularly aggressive subtype that is both difficult to detect and treat. DGC is distinguished by weak cell-cell cohesion, most often due to loss of the cell adhesion protein E-cadherin, a common occurrence in highly invasive, metastatic cancer cells. In this study, we demonstrate that loss-of-function mutation of E-cadherin in DGC cells results in their increased sensitivity to the non-apoptotic, iron-dependent form of cell death, ferroptosis. Homophilic contacts between E-cadherin molecules on adjacent cells suppress ferroptosis through activation of the Hippo pathway. Furthermore, single nucleotide mutations observed in DGC patients that ablate the homophilic binding capacity of E-cadherin reverse the ability of E-cadherin to suppress ferroptosis in both cell culture and xenograft models. Importantly, although E-cadherin loss in cancer cells is considered an essential event for epithelial-mesenchymal transition and subsequent metastasis, we found that circulating DGC cells lacking E-cadherin expression possess lower metastatic ability, due to their increased susceptibility to ferroptosis. Together, this study suggests that E-cadherin is a biomarker predicting the sensitivity to ferroptosis of DGC cells, both in primary tumor tissue and in circulation, thus guiding the usage of future ferroptosis-inducing therapeutics for the treatment of DGC.

Listeria monocytogenes Co-Opts the Host Exocyst Complex To Promote Internalin A-Mediated Entry.

The bacterial pathogen Listeria monocytogenes induces its internalization (entry) into intestinal epithelial cells through interaction of its surface protein, internalin A (InlA), with the human cell-cell adhesion molecule, E-cadherin. While InlA-mediated entry requires bacterial stimulation of actin polymerization, it remains unknown whether additional host processes are manipulated to promote internalization. Here, we show that interaction of InlA with E-cadherin induces the host membrane-trafficking process of polarized exocytosis, which augments uptake of Listeria. Imaging studies revealed that exocytosis is stimulated at sites of InlA-dependent internalization. Experiments inhibiting human N-ethylmaleimide-sensitive factor (NSF) demonstrated that exocytosis is needed for efficient InlA-mediated entry. Polarized exocytosis is mediated by the exocyst complex, which comprises eight proteins, including Sec6, Exo70, and Exo84. We found that Exo70 was recruited to sites of InlA-mediated entry. In addition, depletion of Exo70, Exo84, or Sec6 by RNA interference impaired entry without affecting surface levels of E-cadherin. Similar to binding of InlA to E-cadherin, homophilic interaction of E-cadherin molecules mobilized the exocyst and stimulated exocytosis. Collectively, these results demonstrate that ligation of E-cadherin induces exocytosis that promotes Listeria entry, and they raise the possibility that the exocyst might also control the normal function of E-cadherin in cell-cell adhesion.

Exosomes from EGFR-Mutated Adenocarcinoma Induce a Hybrid EMT and MMP9-Dependant Tumor Invasion.

Simple SummaryExosomes, a class of extra cellular nano-sized vesicles (EVs), and their contents have gained attention as potential sources of information on tumor detection and regulatory drivers of tumor progression and metastasis. We report that exosomes from serum of patients with Epidermal Growth Factor Receptor (EGFR) -mutated non-small cell lung cancer (NSCLC) induce invasion by promoting hybrid EMT. We depict exosomes as valuable actors of metastasis formation and establishment of pre-metastatic niche. Patients with an EGFR mutation are prone to metastatic recurrence. Exosomes should therefore be strongly considered as key players in cancer relapse but also as major actors in the establishment of the pre-metastatic niche.Exosomes, a class of extra cellular nano-sized vesicles (EVs), and their contents have gained attention as potential sources of information on tumor detection and regulatory drivers of tumor progression and metastasis. The effect of exosomes isolated from patients with an Epidermal Growth Factor Receptor (EGFR)-mutated adenocarcinoma on the promotion of epithelial–mesenchymal transition (EMT) and invasion were examined. Exosomes derived from serum of patients with EGFR-mutated non-small cell lung cancer (NSCLC) mediate the activation of the Phosphoinositide 3-kinase (PI3K)/AKT/ mammalian target of rapamycin (mTOR) pathway and induce an invasion through the up-regulation of matrix metalloproteinase-9 (MMP-9) in A549 cells. We observed a significant increase in the expression of vimentin, a mesenchymal marker, while retaining the epithelial characteristics, as evidenced by the unaltered levels of E-cadherin and Epithelial cell adhesion molecule (EPCAM). We also observed an increase of nuclear factor erythroid 2-related factor 2 (NFR2) and P-cadherin expression, markers of hybrid EMT. Exosomes derived from EGFR-mutated adenocarcinoma serum could be a potential mediator of hybrid EMT and tumor invasion. Understanding how cancerous cells communicate and interact with their environment via exosomes will improve our understanding of lung cancer progression and metastasis formation.

Proteomic alterations in extracellular vesicles induced by oncogenic PIK3CA mutations.

PIK3CA is one of the most frequently mutated genes in human cancers, with the two most prevalent activating mutations being E545K and H1047R. Although the altered intracellular signaling pathways in these cells have been described, the effect of these mutations on their extracellular vesicles (EVs) has not yet been reported. To study altered cellular physiology and intercellular communication through proteomic analysis of EVs, MCF10A cells and their isogenic mutant versions (PIK3CA E545K and H1047R) were cultured and their EVs enriched by differential ultracentrifugation. Proteins were extracted, digested with trypsin and the peptides labeled with tandem mass tag (TMT) reagents and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Four thousand six hundred and fifty-five peptides were identified from 579 proteins of which 522 proteins have been previously described in EVs. Relative quantitation revealed altered levels of EV proteins including several cell adhesion molecules. Mesothelin, E-cadherin, and epithelial cell adhesion molecule were elevated in both mutant cell-derived EVs. Markers of tumor invasion and progression like galectin-3 and transforming growth factor beta induced protein were increased in both mutants. Overall, activating mutations in PIK3CA result in altered EV composition with characteristic changes associated with these hotspot mutations.

Inhibiting ADAM10‐MMP14 Complex Blocks Cystogenesis of Kidney Epithelial Cells

BackgroundPolycystic kidney disease (PKD) is the most common genetic kidney disorder. It is characterized by the aberrant renal tubule epithelial cells proliferation leads to the formation of multiple fluid‐filled cysts, and it causes renal failure. Currently, kidney transplant or dialysis is the only effective treatment. A disintegrin‐like metalloproteinase 10 (ADAM10) and matrix metalloproteinase 14 (MMP14) are two major members in the superfamily of metalloproteinases that primarily cleave several cell membrane proteins and growth factors. Inhibition of ADAM10 activity reduces cystic growth of renal epithelial cells, and inhibition of MMP14 also reduces the number of cysts in the kidneys of rats with PKD. In our study, we propose to elucidate the unclear relationship between ADAM10 and MMP14 in the development of cystogenesis in kidney.MethodsMadin‐Darby Canine Kidney (MDCK) cells with stable expression of MMP14 and its mutants were developed and used in our study. MTT proliferation assay was used to measure cell growth. Immunoprecipitation and Western blots were used to determine physical association and proteinase activity. 3‐dimensional (3D) culture of MDCK cells was used to examine cell growth patterns.ResultsWe found that a unique ADAM10‐MMP14 complex forms in cell membrane. The hemopexin domain of MMP14 is essential for its association with ADAM10. Their interaction causes differential cleavage of cell membrane proteins, E‐cadherin and L1 cell adhesion molecule protein (L1CAM). In MDCK cells, only ADAM10 cleaves E‐cadherin but its cleavage is dependent on the active form of MMP14. In addition, both ADAM10 and MMP14 cleave L1CAM but inactive MMP14 blocks the ADAM10 cleavage of L1CAM. We tested the effects of ADAM10 and MMP14 interaction on cell proliferation and cystic growth. Ectopic expression of MMP14 increases cell proliferation and cystic growth of MDCK cells in a 3D culture matrix. Further, use of MMP14‐specific inhibitor NSC405020 or ectopic expression of a dominant‐negative form of MMP14 mutant also results in proper contact inhibition, and further promotes tubular growth of MDCK cells in 3D culture. Inhibition of ADAM10 with siRNA or enzymatic inhibitor GI254023X significantly reduces cell proliferation and promotes tubular growth. Combined use of GI254023X and NSC405020 results in a 73.4 ±8.23% decrease in cell proliferation compared to GI254023X, and 68.6 ± 6.84% decrease compared to NSC405020 alone. In 3D culture, MDCK‐MMP14 (ectopic expression of MMP14) cells form cystic growth only, but addition of both ADAM10 and MMP14 inhibitors leads to tubular growth only.ConclusionOur data identified the solid physical association of ADAM10 and MMP14. Their functional interaction causes differential cleavage of cell membrane proteins, E‐cadherin and L1CAM. Inhibition of ADAM10‐MMP14 complex blocks proliferation and the cystogenesis of of kidney epithelial cells. Individual ADAM10 or MMP14 inhibitors have been used in clinical trials for certain tumors, however, they have never been used together nor have been used in PKD treatments. Our results suggest the combination of ADAM10 and MMP14 inhibitors could be served as a novel effective therapeutic strategy of PKD.

Electroacupuncture improves endometrial receptivity through miRNA-223-3p-mediated regulation of leukemia inhibitory factor / signal transducer and activator of transcription 3 signaling pathway

ABSTRACT Ovulation-inducing drugs such as endogenous steroids could reduce endometrial receptivity during the implantation window, resulting in lower clinical pregnancy rates and higher miscarriage rates. The present study employed electroacupuncture therapy along with different frequencies on elevating impaired endometrial receptivity to elucidate the mechanism therein. The rats were split up into seven groups of normal, model, low-frequency electroacupuncture (LF-EA), high-frequency electroacupuncture (HF-EA), LF-EA+anti-miRNA, HF-EA+anti-miRNA, and anti-miRNA. PCR assays were used to detect miR-223-3p expressions. The effects of electroacupuncture and miR-223-3p on rats’ endometrial membrane cell-drinking process in a manner of scanning electron microscopy were recorded. After that we observed on the electroacupuncture effects on the conditions of adhesion molecules and LIF/STAT3 signaling pathway with assays of immunofluorescence and Western Blot. This study was end up with dual luciferase assay, where combination of miR-233-3p onto the 3’-UTR sequence of LIF was determined. PCR assay demonstrated that HF-EA procured an inhibition in miR-223-3p expression, whereas scanning electron microscopy turned out that both electroacupuncture and miR-223-3p were capable of raising the amount of intrauterine pinocytosis and the number of blastocyst implantation in rats. Additionally, assays of Western Blot and immunofluorescence showed that therapy of electroacupuncture brought about decreasing expressions in adhesion molecules of E-cadherin, β-catenin and claudin-1 (CLDN1). We found that both electroacupuncture and miR-223-3p were able to fortify LIF/STAT3 signaling pathway, then the fact of miR-223-3p combination to LIF 3’-UTR sequence was validated via our dual-luciferase assay. Electroacupuncture therapy inhibited the miR-223-3p expression upon LIF/STAT3 signaling pathway to elevate endometrial receptivity.

Neutrophil extracellular traps drive epithelial–mesenchymal transition of human colon cancer

Neutrophil extracellular traps (NETs) are extracellular structures, composed of nuclear DNA and various proteins released from neutrophils. Evidence is growing that NETs exert manifold functions in infection, immunity and cancer. Recently, NETs have been detected in colorectal cancer (CRC) tissues, but their association with disease progression and putative functional impact on tumourigenesis remained elusive. Using high-resolution stimulated emission depletion (STED) microscopy, we showed that citrullinated histone H3 (H3cit) is sufficient to specifically detect citrullinated NETs in colon cancer tissues. Among other evidence, this was supported by the close association of H3cit with de-condensed extracellular DNA, the hallmark of NETs. Extracellular DNA was reliably differentiated from nuclear condensed DNA by staining with an anti-DNA antibody, providing a novel and valuable tool to detect NETs in formalin-fixed paraffin-embedded tissues. Using these markers, the clinical association of NETs was investigated in a cohort of 85 patients with colon cancer. NETs were frequently detected (37/85, 44%) in colon cancer tissue sections and preferentially localised either only in the tumour centre or both in the tumour centre and the invasive front. Of note, citrullinated NETs were significantly associated with high histopathological tumour grades and lymph node metastasis. In vitro, purified NETs induced filopodia formation and cell motility in CRC cell lines. This was associated with increased expression of mesenchymal marker mRNAs (vimentin [VIM], fibronectin [FN1]) and epithelial-mesenchymal transition promoting transcription factors (ZEB1, Slug [SNAI2]), as well as decreased expression of the epithelial markers E-cadherin (CDH1) and epithelial cell adhesion molecule (EPCAM). These findings indicated that NETs activate an epithelial-mesenchymal transition-like process in CRC cells and may contribute to the metastatic progression of CRC. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The Autophagic Route of E-Cadherin and Cell Adhesion Molecules in Cancer Progression.

Simple SummaryA hallmark of carcinoma progression is the loss of epithelial integrity. In this context, the deregulation of adhesion molecules, such as E-cadherin, affects epithelial structures and associates with epithelial to mesenchymal transition (EMT). This, in turn, fosters cancer progression. Autophagy endows cancer cells with the ability to overcome intracellular and environmental stress stimuli, such as anoikis, nutrient deprivation, hypoxia, and drugs. Furthermore, it plays an important role in the degradation of cell adhesion proteins and in EMT. This review focuses on the interplay between the turnover of adhesion molecules, primarily E-cadherin, and autophagy in cancer progression.Cell-to-cell adhesion is a key element in epithelial tissue integrity and homeostasis during embryogenesis, response to damage, and differentiation. Loss of cell adhesion and gain of mesenchymal features, a phenomenon known as epithelial to mesenchymal transition (EMT), are essential steps in cancer progression. Interestingly, downregulation or degradation by endocytosis of epithelial adhesion molecules (e.g., E-cadherin) associates with EMT and promotes cell migration. Autophagy is a physiological intracellular degradation and recycling process. In cancer, it is thought to exert a tumor suppressive role in the early phases of cell transformation but, once cells have gained a fully transformed phenotype, autophagy may fuel malignant progression by promoting EMT and conferring drug resistance. In this review, we discuss the crosstalk between autophagy, EMT, and turnover of epithelial cell adhesion molecules, with particular attention to E-cadherin.

High-frequency electroacupuncture improves endometrial receptivity via regulating cell adhesion molecules and leukemia inhibitory factor / signal transducer and activator of transcription signaling pathway

ABSTRACT Controlled ovarian hyperstimulation (COH) impairs the endometrium receptivity during the implantation window, resulting in a lower clinical pregnancy rate and a higher abortion rate. Our study explored the effect of electroacupuncture on the endometrial receptivity of COH rats. Female rats were randomly divided into normal treatment (Normal), model treatment (Model), low-frequency electroacupuncture treatment (LF-EA) and high-frequency electroacupuncture treatment (HF-EA). Rats in the Model, LF-EA, and HF-EA treatment groups were injected with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (HCG) to establish a model of COH rats. Compared with the Normal, the endometrial thickness, the number of pinopodes and amount of blastocyst implantation in the Model group were significantly reduced. Among them, the endometrial thickness and the amount of blastocyst implantation in the Model group were substantially decreased than those in the HF-EA group. High-frequency electroacupuncture treatment could markedly reduce the protein expression levels of E-cadherin, β-catenin and claudin-1 (CLDN1). During HF-EA treatment, the LIF/STAT3 signaling pathway of COH rats was enhanced. In conclusion, electroacupuncture could improve the endometrium receptivity and promote the blastocyst implantation in COH rats by reducing cell adhesion molecules and enhancing the LIF/STAT3 signaling pathway. Highlights High-frequency electroacupuncture could effectively improve endometrial receptivity and blastocyst implantation amount in COH rats. Electroacupuncture, especially high-frequency electroacupuncture, could significantly increase endometrial thickness and the number of pinopodes. High-frequency electroacupuncture significantly reduced the protein expression levels of E-cadherin, β-catenin and CLDN1 adhesion molecules in COH rats. High-frequency electroacupuncture could markedly enhance the LIF/STAT3 signaling pathway in COH rats.

Hyaluronic Acid-Modified Nanoparticles Self-Assembled from Linoleic Acid-Conjugated Chitosan for the Codelivery of miR34a and Doxorubicin in Resistant Breast Cancer.

In this study, a chitosan-based, self-assembled nanosystem that codelivered microRNA34a (miR34a) and doxorubicin (Dox) with hyaluronic acid (HA) modification (named CCmDH NPs) was developed to reverse the resistance of breast cancer (BCa) cells to Dox. The CCmDH NPs had a diameter of 180 ± 8.3 nm and a ζ potential of 16.5 mV with a slow-release effect for 96 h. The codelivery system could protect miR34a from nuclease and serum degradation and transport miR34a and Dox into drug-resistant MCF-7/A cells. In addition, the CCmDH NPs could inhibit proliferation and promote apoptosis by regulating the protein expression of B-cell lymphoma-2 (Bcl-2) and poly(ADP-ribose) polymerase (PARP) and inhibit invasion, metastasis, and adhesion by regulating E-cadherin, N-cadherin, MMP2, CD44, and Snail molecules. The CCmDH NPs induced a 73.7% tumor reduction in xenograft tumor growth in nude mice in vivo. This study provides evidence for the anticancer activity of CCmDH NPs carrying Dox and miR34a in BCa, especially metastatic Dox-resistant BCa models.

Runx2 deficiency in junctional epithelium of mouse molars decreases the expressions of E-cadherin and junctional adhesion molecule 1.

Junctional epithelium (JE) attaching to the enamel surface seals gaps around the teeth, functioning as the first line of gingival defense. Runt-related transcription factor 2 (Runx2) plays a role in epithelial cell fate, and the deficiency of Runx2 in JE causes periodontal destruction, while its effect on the barrier function of JE remains largely unexplored. In the present study, hematoxylin-eosin (H&E) staining revealed the morphological differences of JE between wild-type (WT) and Runx2 conditional knockout (cKO) mice. We speculated that these changes were related to the down-regulation of E-cadherin (E-cad), junctional adhesion molecule 1 (JAM1), and integrin β6 (ITGB6) in JE. Moreover, immunohistochemistry (IHC) was conducted to assess the expressions of these proteins. To verify the relationship between Runx2 and the three above-mentioned proteins, human gingival epithelial cells (HGEs) were cultured for in vitro experiment. The expression of Runx2 in HEGs was depleted by lentivirus. Quantitative real-time PCR (qRT-PCR) and Western blotting analysis were adopted to analyze the differences in mRNA and protein expressions. Taken together, Runx2 played a crucial role in maintaining the structure and function integrality of JE via regulating the expressions of E-cad and JAM1.

Comparative Analysis of Cell-Cell Contact Abundance in Ovarian Carcinoma Cells Cultured in Two- and Three-Dimensional In Vitro Models.

Simple SummaryTumor resistance to therapy is a crucial problem of today’s oncology. The emerging data indicate that tumor microenvironment is the key participant in the resistance development. One of the most basic aspect of tumor microenvironment is intercellular adhesion. Our data obtained using monolayer culture, matrix-free and matrix-based three-dimensional in vitro models indicate that the abundance of cell-cell contact proteins is varying depending on the microenvironment. These differences coincided with the degree of the resistance to therapeutics. The importance of adhesion proteins in tumor resistance may provide the fundamental basis for improving cancer treatment approaches and must be taken into account when screening candidate drugs. Tumor resistance to therapy is associated with the 3D organization and peculiarities of the tumor microenvironment, of which intercellular adhesion is a key participant. In this work, the abundance of contact proteins was compared in SKOV-3 and SKOV-3.ip human ovarian adenocarcinoma cell lines, cultivated in monolayers, tumor spheroids and collagen hydrogels. Three-dimensional models were characterized by extremely low expression of basic molecules of adherens junctions E-cadherin and demonstrated a simultaneous decrease in desmosomal protein desmoglein-2, gap junction protein connexin-43 and tight junction proteins occludin and ZO-1. The reduction in the level of contact proteins was most pronounced in collagen hydrogel, accompanied by significantly increased resistance to treatment with doxorubicin and targeted anticancer toxin DARPin-LoPE. Thus, we suggest that 3D models of ovarian cancer, especially matrix-based models, tend to recapitulate tumor microenvironment and treatment responsiveness to a greater extent than monolayer culture, so they can be used as a highly relevant platform for drug efficiency evaluation.

Crystal structure of Leptospira leucine-rich repeat 20 reveals a novel E-cadherin binding protein to induce NGAL expression in HK2 cells.

Leptospirosis is the most common zoonotic disease caused by pathogenic Leptospira, which is classified into three groups according to virulence. Its pathogenic and intermediate species contain leucine-rich repeat (LRR) proteins that are rarely expressed in non-pathogenic strains. In this study, we presented the crystal structure of LSS_11580 (rLRR20) from pathogenic L. santarosai serovar Shermani. X-ray diffraction at a resolution of 1.99 Å revealed a horseshoe-shaped structure containing seven α-helices and five β-sheets. Affinity assays indicated that rLRR20 interacts with E-cadherin on the cell surface. Interestingly, its binds to the extracellular (EC) 1 domain in human epithelial (E)-cadherin, which is responsible for binding to another E-cadherin molecule in neighboring cells. Several charged residues on the concave face of LRR20 were predicted to interact with EC1 domain. In the affinity assays, these charged residues were replaced by alanine, and their affinities to E-cadherin were measured. Three vital residues and mutation variants of LRR20, namely D56A, E59A, and E123A, demonstrated significantly reduced affinity to E-cadherin compared with the control. Besides, we also demonstrated that rLRR20 induced the expression of neutrophil gelatinase-associated lipocalin (NGAL) in HK2 cells. The low ability of the three mutation variants to induce NGAL expression further demonstrates this induction. The present findings indicate that LRR20 from pathogenic Leptospira binds to E-cadherin and interacts with its EC1 domain. In addition, its induction of NGAL expression in HK2 cells is associated with acute kidney injury in human.

&lt;p&gt;Circadian Clock Protein PERIOD2 Suppresses the PI3K/Akt Pathway and Promotes Cisplatin Sensitivity in Ovarian Cancer&lt;/p&gt;

BackgroundThe mortality rate of ovarian cancer is the highest among gynecological tumors. The two factors leading to high mortality of ovarian cancer are late clinical stage and chemotherapy resistance. It is very important to reverse or intervene chemotherapy resistance. Abnormal circadian rhythm is related to the occurrence of tumor, and circadian clock protein PERIOD2 (PER2) acts as a tumor suppressor in cancer; however, little is known about its involvement in chemosensitivity.MethodsThis study aimed to investigate the role and underlying mechanisms of PER2 in ovarian cancer sensitivity to cisplatin. Overexpression and knockdown of PER2 were performed to explore its role in ovarian cancer cell sensitivity to cisplatin both in vitro and in vivo. The protein levels of PI3K, AKT, caspase 3, E-cadherin, and other drug resistance-related molecules were determined in parental SKOV3 and SKOV3/DDP cells as well as in xenograft tumor tissues.ResultsCompared with parental cells, SKOV3/DDP cells had dramatically decreased PER2 expression, possibly due to hypermethylation in the PER2 promoter. PER2 overexpression significantly inhibited proliferation while promoting cisplatin-induced apoptosis in SKOV3 and SKOV3/DDP cells. In agreement, PER2-overexpressing SKOV3/DPP cells yielded significantly reduced tumor mass in cisplatin-treated mice compared with control cells. Mechanistically, PER2 overexpression remarkably reduced the protein amounts of PI3K, AKT, and MDR1 while increasing those of caspase 3 and E-cadherin in tumor tissues. Knockdown of PER2 exhibited opposite effects. PER2 overexpression also reduced the serum levels of TNF-α and IL-6 in tumor-bearing mice before the initiation of cisplatin treatment.ConclusionThis study suggests that loss of PER2 contributes to cisplatin resistance in SKOV3 cells, possibly by activating the PI3K/AKT pathway and EMT, inhibiting apoptosis, and promoting drug efflux and inflammatory responses. Overexpression of PER2 could reverse these alterations and sensitize both parental SKOV3 and SKOV3/DDP cells to cisplatin.