Carcinoma cells induce lumen filling and EMT in epithelial cells through soluble E-cadherin-mediated activation of EGFR

E-cadherin interacts with EGFR resulting in hyper-activation of ERK in multiple models of breast cancer

The loss of intercellular adhesion molecule E-cadherin is a hallmark of the epithelial-mesenchymal transition (EMT), during which tumor cells transition into an invasive phenotype. Accordingly, E-cadherin has long been considered a tumor suppressor gene; however, E-cadherin expression is paradoxically correlated with breast cancer survival rates. Using novel multi-compartment organoids and multiple in vivo models, we show that E-cadherin promotes a hyper-proliferative phenotype in breast cancer cells via interaction with the transmembrane receptor EGFR. The E-cad and EGFR interaction results in activation of the MEK/ERK signaling pathway, leading to a significant increase in proliferation via activation of transcription factors, including c-Fos. Pharmacological inhibition of MEK activity in E-cadherin positive breast cancer significantly decreases both tumor growth and macro-metastasis in vivo. This work provides evidence for a novel role of E-cadherin in breast tumor progression and identifies a new target to treat hyper-proliferative E-cadherin-positive breast tumors, thus providing the foundation to utilize E-cadherin as a biomarker for specific therapeutic success.

Cancer cells corrupt normal epithelial cells through miR-let-7c-rich small extracellular vesicle-mediated downregulation of p53/PTEN

Tumor volume increases continuously in the advanced stage, and aside from the self-renewal of tumor cells, whether the oncogenic transformation of surrounding normal cells is involved in this process is currently unclear. Here, we show that oral squamous cell carcinoma (OSCC)-derived small extracellular vesicles (sEVs) promote the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of normal epithelial cells but delay their apoptosis. In addition, nuclear-cytoplasmic invaginations and multiple nucleoli are observed in sEV-treated normal cells, both of which are typical characteristics of premalignant lesions of OSCC. Mechanistically, miR-let-7c in OSCC-derived sEVs is transferred to normal epithelial cells, leading to the transcriptional inhibition of p53 and inactivation of the p53/PTEN pathway. In summary, we demonstrate that OSCC-derived sEVs promote the precancerous transformation of normal epithelial cells, in which the miR-let-7c/p53/PTEN pathway plays an important role. Our findings reveal that cancer cells can corrupt normal epithelial cells through sEVs, which provides new insight into the progression of OSCC.

MiR-509-3p is oncogenic, targets the tumor suppressor PHLPP2, and functions as a novel tumor adjacent normal tissue based prognostic biomarker in colorectal cancer

Background

Recently the role of microRNAs has been explored immensely as novel regulators and potential biomarkers in several cancers. MiR-509-3p is one such miRNA that has been observed to show a mixed expression in different cancers, while it’s expression and clinical relevance in colorectal cancer (CRC) has not yet been characterized.

Methods

We used quantitative PCR to evaluate the expression of miR-509-3p in fresh-frozen CRC tumor tissues and the corresponding tumor-adjacent normal (NAT) tissues from 103 patients. Subsequently, functional studies were performed to further interpret the role of the miRNA in CRC.

Results

MiR-509-3p was found to be overexpressed in CRC tissues in nearly 80% of cases and was associated with an aggressive disease presentation. Notably, a higher expression of the miRNA promoted cell proliferation, migration, and invasion of CRC cells in in vitro and in vivo models. Mechanistically, we confirmed that miR-509-3p directly binds the 3’UTR of the tumor suppressor PHLPP2 and inhibits its expression. Furthermore, within the previous 103 clinical tissue specimens, we observed an overexpression of miR-509-3p within the NAT tissue of patients associated with a poor disease prognosis. Using multivariate analysis, it was observed that the expression of miR-509-3p within the NAT tissue was an independent predictor of prognosis in CRC. At the cellular level, through indirect coculture experiments, miR-509-3p was observed to regulate the proliferative, migratory, and invasive behavior of normal colon cells.

Conclusion

MiR-509-3p strongly contributes to the development and progression of CRC and can potentially function as a prognostic biomarker in the disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09075-x.

SNU-333 Cells as an Appropriate Cell Line for the Orthotopic Renal Cell Carcinoma Model

Objective: To investigate a feasible candidate for an appropriate cell line for the orthotopic renal cell carcinoma (RCC) model. Methods: Normal human proximal tubule cells (HK-2) and RCC cells were used for MTT assay, Western blotting, sphere-forming assay, and orthotopic injection of BALB/c-nude mice. Immunohistochemistry was adopted in tissue arrays and orthotopic tumors. Results: Primary RCC cells showed resistance to a GPX4 inhibitor compared to HK-2 and to metastatic RCC cells, Caki-1. Caki-2 and SNU-333 cells showed resistance to ferroptosis via increased GPX4 and FTH1, respectively. RCC cells showed increased αSMA, in which Caki-2 and SNU-333 cells exhibited different epithelial–mesenchymal transition and cancer stem cell markers. Caki-1 and SNU-333 cells formed spheres in vitro and orthotopic tumor masses in vivo. The injected SNU-333 tumor only showed high intensities of CD10 and PAX8, markers of renal origin. Conclusion: SNU-333 cell line exhibited resistance via iron metabolism and stemness, and had tumor-initiating capacities in vitro and in vivo. These results suggest that among the cells tested, SNU-333 cells were the most promising for the establishment of an orthotopic RCC model for further researches.

S100A4 Is Involved in Stimulatory Effects Elicited by the FGF2/FGFR1 Signaling Pathway in Triple-Negative Breast Cancer (TNBC) Cells

Triple-negative breast cancer (TNBC) is an aggressive breast tumor subtype characterized by poor clinical outcome. In recent years, numerous advancements have been made to better understand the biological landscape of TNBC, though appropriate targets still remain to be determined. In the present study, we have determined that the expression levels of FGF2 and S100A4 are higher in TNBC with respect to non-TNBC patients when analyzing “The Invasive Breast Cancer Cohort of The Cancer Genome Atlas” (TCGA) dataset. In addition, we have found that the gene expression of FGF2 is positively correlated with S100A4 in TNBC samples. Performing quantitative PCR, Western blot, CRISPR/Cas9 genome editing, promoter studies, immunofluorescence analysis, subcellular fractionation studies, and ChIP assays, we have also demonstrated that FGF2 induces in TNBC cells the upregulation and secretion of S100A4 via FGFR1, along with the ERK1/2–AKT–c-Rel transduction signaling. Using conditioned medium from TNBC cells stimulated with FGF2, we have also ascertained that the paracrine activation of the S100A4/RAGE pathway triggers angiogenic effects in vascular endothelial cells (HUVECs) and promotes the migration of cancer-associated fibroblasts (CAFs). Collectively, our data provide novel insights into the action of the FGF2/FGFR1 axis through S100A4 toward stimulatory effects elicited in TNBC cells.

Chiral Analysis of Lactate during Direct Contact Coculture by Single-Cell On-Probe Enzymatic Dehydrogenation Derivatization: Unraveling Metabolic Changes Caused by d-Lactate

In vitro noncontact cell-based coculture models are frequently employed to study cell-to-cell communication. However, these models cannot accurately represent the complexity of in vivo signaling. d-Lactate is an unusual metabolite produced and released by cancer cells. The characterization of d-lactate is challenging as it shares the same mass but has much lower amounts compared with l-lactate. Herein, d-α-hydroxy acids were specifically recognized and dehydrogenated by d-α-hydroxy acid dehydrogenase. The dehydrogenation products were rapidly quaternized for enhancement of mass signals. An on-probe enzymatic dehydrogenation-derivatization method was proposed for chiral analysis of α-hydroxy acids at the single-cell level. It is a promising amplification methodology and affords over 3 orders of magnitude signal enhancement. Furthermore, direct contact coculture models were used to precisely mimic the tumor microenvironment and explore the communication between cancer and normal cells. Single-cell mass spectrometry (SCMS) was further applied to easily sample cell extracts and study the differences of the aspects of small molecule metabolism in cocultured cells. On the basis of direct contact coculture SCMS, several differential small molecule metabolites and differences of oxidative stress between cocultured and monocultured normal cells were successfully detected. Additionally, d-lactate was discovered as a valuable differential metabolite with application of the two developed methods. It may account for the cancer-associated metabolic behavior of normal cells. These changes could be relieved after d-lactate metabolism-related drug treatment. This discovery may promote the investigation of d-lactate metabolism, which may provide a novel direction for cancer therapy.

Migration of BEAS-2B cells enhanced by H1299 cell derived-exosomes

Previous studies reported that exosomes (Exos) secreted by tumor cells could affect the tumor cells themselves and normal cells. However, the effects of exosomes derived from tumor cells on normal cells' migration and mechanical characteristics are rarely reported. This work explores the effects of H1299 cell-derived exosomes (H1299-Exos) on the migration of BEAS-2B cells, and analyzes possible mechanical mechanisms. In the experiments, exosomes were isolated from the culture supernatants of H1299 cells by ultracentrifugation. The H1299-Exos were confirmed by scanning electron microscope (SEM) and western blotting (WB). The BEAS-2B cell migration was assessed using scratch assays. Cytoskeletal structure changes were detected by immunofluorescence. Surface morphology and mechanical properties were measured by atomic force microscopy (AFM). After incubation with H1299-Exos for 48 h, BEAS-2B cells enhanced migration ability, with increased filopodia and cytoskeletal rearrangements. The changes in the morphology and mechanical properties of the cells caused by H1299-Exos were detected using AFM, including the increase in cell length and the decrease in cell height, Young's modulus and adhesion. In short, H1299-Exos promoted the BEAS-2B cell migrations. It indicates that the morphological and mechanical properties can be used as a means to assess normal cell alterations induced by tumor cell derived-exosomes. This provides a method for studying the effects of exosomes secreted by tumor cells on normal cells and the changes in their physical properties.

Elevated soluble E-cadherin during the epithelial-mesenchymal transition process and as a diagnostic marker in colorectal cancer

Epithelial-mesenchymal transition (EMT) plays a crucial role in colorectal cancer (CRC) metastasis. Soluble E-cadherin (sE-cadherin) is a peptide degradation product of the E-cadherin, a key epithelial molecule of EMT. However, it is not known if elevated levels of sE-cadherin also occur during EMT. And the study of sE-cadherin in colorectal cancer is rare. The purpose of the study was to evaluate the relationship between sE-cadherin and EMT in CRC and to evaluate the diagnostic value of sE-cadherin as a serum marker for CRC. Transforming growth factor-β1 (TGF-β1) was used to induce EMT in HT29 and SW480 cells. The cells treated with TGF-β1 showed morphological and biological behavior changes consistent with EMT. Western blot and ELISA showed the levels of sE-cadherin were increased during EMT in CRC cells. In addition, we intravenously injected luciferase-labeled SW480 cells into nude mice to construct CRC metastasis model. Following the elongation of time, the fluorescence intensity of the experimental group was gradually increased. Correspondingly, the serum concentration of sE-cadherin also increased during CRC metastasis in mice. Furthermore, compared to healthy subjects, significantly higher levels of serum sE-cadherin were also observed in CRC patients and correlated with clinicopathological features. For discriminating CRC from healthy controls, the area under the receiver operating characteristic (ROC) curve (AUC) of sE-cadherin was 0.853, while the optimal cut-off point was set at 5928.16 ng/ml, the diagnostic sensitivity was 73.9% and the specificity was 80%. Compared with current commercial biomarkers (CEA, CA19-9 and CA125), the diagnostic performance of sE-cadherin was highest. Combined sE-cadherin and CEA raised the sensitivity to 82.4%. Serum sE-cadherin level can be used as a potential diagnostic biomarker of CRC.

Colorectal cysts as a validating tool for CAR therapy

Background

Treatment of cancers has largely benefited from the development of immunotherapy. In particular, Chimeric Antigen Receptor (CAR) redirected T cells have demonstrated impressive efficacy against B-cell malignancies and continuous efforts are made to adapt this new therapy to solid tumors, where the immunosuppressive tumor microenvironment is a barrier for delivery. CAR T-cell validation relies on in vitro functional assays using monolayer or suspension cells and in vivo xenograft models in immunodeficient animals. However, the efficacy of CAR therapies remains difficult to predict with these systems, in particular when challenged against 3D organized solid tumors with highly intricate microenvironment. An increasing number of reports have now included an additional step in the development process in which redirected T cells are tested against tumor spheres.

Results

Here, we report a method to produce 3D structures, or cysts, out of a colorectal cancer cell line, Caco-2, which has the ability to form polarized spheroids as a validation tool for adoptive cell therapy in general. We used CD19CAR T cells to explore this method and we show that it can be adapted to various platforms including high resolution microscopy, bioluminescence assays and high-throughput live cell imaging systems.

Conclusion

We developed an affordable, reliable and practical method to produce cysts to validate therapeutic CAR T cells. The integration of this additional layer between in vitro and in vivo studies could be an important tool in the pre-clinical workflow of cell-based immunotherapy.

Curcumin Inhibits the Migration and Invasion of Non-Small-Cell Lung Cancer Cells Through Radiation-Induced Suppression of Epithelial-Mesenchymal Transition and Soluble E-Cadherin Expression

Radiotherapy has been reported to cause cancer metastasis. Thus, a new strategy for radiotherapy must be developed to avoid this side effect. A549 cells were exposed to radiation to induce an epithelial-mesenchymal transition (EMT) cell model. Real-time PCR and western blotting were used to detect mRNA and protein expression levels, and Transwell invasion and wound healing assays were used to detect cell migration and invasion. ELISA was used to detect soluble E-cadherin (sE-cad) secretion. siRNA was used to silence MMP9 expression. The results show that A549R cells exhibited an EMT phenotype with increased E-cadherin, N-cadherin, Snail, Slug, vimentin and Twist expression and decreased pan-keratin expression. sE-cad levels were increased in A549R cells and in the serum of NSCLC patients with distant metastasis. Exogenous sE-cad treatment and sE-cad overexpression promoted A549R and A549 cell migration and invasion. In contrast, blocking sE-cad attenuated A549 cell migration and invasion. Curcumin inhibited sE-cad expression and reversed EMT induced by radiation. Furthermore, curcumin suppressed sE-cad-enhanced A549 and A549R cell migration and invasion. Curcumin inhibited MMP9 expression, and silencing MMP9 suppressed sE-cad expression. Taken together, we found a nonclassic EMT phenomenon induced by radiation. Curcumin inhibits NSCLC migration and invasion by suppressing radiation-induced EMT and sE-cad expression by decreasing MMP9 expression.

Soluble E-cadherin is associated with oxidative stress in patients with chronic HBV infection

Mounting evidence indicates that serum soluble E-cadherin (sE-cadherin) serves as an important player in various physiological and pathological processes. However, the crosstalk between serum sE-cadherin and oxidative stress in chronic hepatitis B (CHB) remains to be illustrated. The main purpose of this study is to explore the molecular mechanisms underlying the function of sE-cadherin in CHB virus infection. Levels of serum sE-cadherin, total antioxidant capacity (TAC), glutathione (GSH), superoxide dismutase (SOD), total oxidant activity (TOA), NADPH oxidase 2 (NOX2), and malondialdehyde (MDA), from 51 patients with hepatitis B envelope antigen (HBeAg)-negative CHB, 54 patients with HBeAg-positive CHB, and 109 healthy individuals were detected by enzyme-linked immunosorbent assay. In our study, patients with CHB showed significantly higher serum sE-cadherin levels than healthy individuals (P < .01). Furthermore, we also found that the serum sE-cadherin levels were significantly negatively correlated with TAC, antioxidant enzymes (GSH and SOD) in patients with CHB, and that serum sE-cadherin concentrations were significantly positively correlated with liver enzyme markers (alanine transaminase and aspartate aminotransferase) and oxidative markers (TOA, NOX2, and MDA) in patients with CHB. Therefore, serum sE-cadherin may act as a new candidate biomarker for reflecting inflammation and oxidative stress status in the development and progression of hepatitis B virus infection.

Contribution of fibroblasts to tunnel formation and inflammation in hidradenitis suppurativa/ acne inversa

The precise pathogenic mechanisms in the development, persistence and worsening of hidradenitis suppurativa (HS) remain ill-defined. This chronic inflammatory dermatosis displays a strong Th1 and Th17 inflammatory signature with elevated levels of TNF-α, IL-1β, IL-17 and IFNγ in lesional and perilesional tissue. HS significantly differs to other chronic inflammatory dermatoses due to the development of hypertrophic scarring and dermal tunnels. The development of scarring and tunnels suggests that fibroblastic stromal cells (including myofibroblasts, fibroblasts, pericytes etc) may be involved in the development and progression of disease. Heterogeneous populations of fibroblasts have been identified in other inflammatory disorders and malignancy which contribute to inflammation and present novel therapeutic targets for fibrotic disorders. Findings in HS are consistent with these fibroblast subpopulations and may contribute to tunnel formation, aggressive squamous cell carcinoma and the phenotypic presentation of familial HS variants. We describe the existing knowledge regarding these mechanistic pathways and methods to confirm their involvement in the pathogenesis of HS.

Implications of soluble E-cadherin level of antiviral treatment in patients with chronic hepatitis C virus infection

BACKGROUND AND AIMS

Soluble E-cadherin (sE-cadherin) has been observed elevated in patients with various diseases, and implicated in the occurrence and development of those diseases. The implications of sE-cadherin in chronic hepatitis C virus (HCV) infection are still unclear. The purpose of this study is to explore the significance of sE-cadherin in chronic hepatitis C infection and the correlation with treatment response.

METHODS

87 chronic HCV infected patients and 60 healthy subjects were enrolled in this study. Blood samples from patients receiving the combined treatment of pegylated interferon-a (Peg-IFN-α) with ribavirin (RBV) were collected before treatment, during 4th, 12th therapy weeks, end of the treatment, and 24 weeks post-therapy. Plasma sE-cadherin level was detected by enzyme-linked immunosorbent assay (ELISA) and the relationship between sE-cadherin and antiviral treatment outcome was analyzed.

RESULTS

Plasma sE-cadherin concentrations of Chronic HCV infected patients were significantly higher than that of healthy controls. A strong correlation between sE-cadherin level and the HCV viral load, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and also glutamyl transpeptidase (GGT) level was detected. Chronic HCV infected patients achieving rapid virological response (RVR) and sustained virological response (SVR) had lower baseline sE-cadherin concentrations compared with the non-RVR and non-SVR groups respectively. Univariate and multivariate regression analyses suggested that baseline plasma sE-cadherin level was predictive of therapeutic effect in patients with chronic HCV infection.

CONCLUSION

Baseline sE-cadherin level could be considered as an independent predictor of SVR with Peg-IFN-α plus ribavirin therapy in the Chinese Han population chronic HCV infection patients. Effective antiviral therapy might restore sE-cadherin at physiological levels.

CUL1 Knockdown Attenuates the Adhesion, Invasion, and Migration of Triple-Negative Breast Cancer Cells via Inhibition of Epithelial-Mesenchymal Transition

Cullin-1 (CUL1) is an important factor for tumor growth and a potential therapeutic target for breast cancer therapy, but the molecular mechanism in triple-negative breast cancer (TNBC) is unknown. In the present study, CUL1 shRNA was transfected into BT549 and MDA-MB-231 breast cancer cells. Cell morphology, adhesion, invasion, and migration assays were carried out in the CUL1 knockdown cells. Additionally, protein expression levels of epithelial-mesenchymal transition (EMT)-related factors, Akt phosphorylation at S473 (pAkt), glycogen synthase kinase-3β phosphorylation at ser9 (pGSK3β), cytoplasmic and nuclear β-catenin, and epidermal growth factor receptor phosphorylation at Tyr1068 (pEGFR) were detected by Western blot analysis. CUL1 knockdown significantly suppressed the adhesion, invasion and migration capabilities of the cells, and decreased the expression of Snail1/2, ZEB1/2, Twist1/2, Vimentin, and increased the expression of Cytokeratin 18 (CK18). Moreover, CUL1 knockdown significantly downregulated the phosphorylated levels of Akt, GSK3β, and EGFR, inhibiting the translocation of β-catenin from the cytoplasm to the nucleus. The results indicate that CUL1 knockdown prohibited the metastasis behaviors of breast cancer cells through downregulation (dephosphorylation) of the EMT signaling pathways of EGFR and Akt/GSK3β/β-catenin in breast cancer. These results strongly suggested that reinforcement of the EMT might be a key for CUL1 to accelerate TNBC metastasis.

sE-cadherin is upregulated in serum of patients with renal cell carcinoma and promotes tumor cell dissemination in vitro

INTRODUCTION

Cadherin family proteins are involved in the tumorigenesis of several malignancies. However, their significance in renal cell carcinoma (RCC) has not been extensively investigated. The current study investigates the potential of several cadherins to perform as biomarkers for tumor detection and exert functional RCC activity.

METHODS

Pre- and postoperative concentrations of sE-cadherin, cadherin-6, N-cadherin, cadherin-11, cadherin-17, and cadherin-5 were measured in serum of patients undergoing surgery for RCC and correlated to clinical and histopathological parameters. Control serum was obtained from healthy volunteers. A498 and Caki-1 cells were incubated with sE-cadherin and assessed for cell growth, adhesion, and chemotaxis.

RESULTS

sE-cadherin was significantly upregulated in RCC patients, as compared to controls, and discriminated them with striking accuracy (area under the curve value 0.83). Serum levels remained stable several days after surgery. Treating A498 and Caki-1 cancer cells with various concentrations of sE-cadherin attenuated cell growth and adhesion, while chemotaxis was augmented.

CONCLUSIONS

sE-cadherin is overexpressed in serum of RCC patients and provides a functional cellular switch from sessility to aggressive dissemination. While sE-cadherin is not tumor-specific and thus inappropriate for population-based screening, further studies are warranted to investigate its role in monitoring RCC and employing it as a therapeutic target.

Interleukin-18 expression in oral squamous cell carcinoma: its role in tumor cell migration and invasion, and growth of tumor cell xenografts

Oral squamous cell carcinoma (OSCC) is one of the most common head and neck malignancies. Advanced stages of the disease are associated with poor survival, highlighting a need for new treatment modalities. We previously showed that the proinflammatory cytokine interleukin‐18 (IL‐18) has a tumor suppressive role in OSCC. Here, we investigated the effects of IL‐18 on proliferation, migration, and invasion of OSCC cells ex vivo and in vitro, and in nude mouse xenografts. We report that expression of tankyrase 2 (TNKS2), β‐catenin, and N‐cadherin was higher in tumor cells than in normal mucosae, whereas the expression of IL‐18 and E‐cadherin was higher in normal than in tumor tissues. Elevated expression of IL‐18 (P < 0.01) and E‐cadherin (P = 0.034) was associated with tumor differentiation, whereas expression of TNKS2 (P < 0.01), β‐catenin (P = 0.012), and N‐cadherin (P < 0.01) was associated with tumor de‐differentiation. Furthermore, compared with the vector control, IL‐18 overexpression promoted tumor cell migration and invasion (P < 0.01), but inhibited growth of tumor cell xenografts (P < 0.05). At the protein level, expression levels of IL‐18 (P < 0.01), TNKS2 (P = 0.045), β‐catenin (P = 0.028), and N‐cadherin (P = 0.068) were upregulated in tumor cells after IL‐18 overexpression compared with those of the vector control mice, whereas expression levels of E‐cadherin (P = 0.045) were decreased. In conclusion, our data suggest that IL‐18 overexpression induces oral SCC cell invasion and metastasis by promoting the tumor cell epithelial–mesenchymal transition via the Wnt/β‐catenin signaling pathway.

Oncogenic transformation of normal breast epithelial cells co-cultured with cancer cells

The heterogeneity in human breast cancer poses a challenge for effective treatment. Better understanding of tumor initiation and development will help to resolve this problem. Current models explaining intratumoral diversity include cancer stem cells, clonal evolution and cancer cell dedifferentiation and reprogramming. Herein, a new model, cancer transmission, is proposed to explain cancer heterogeneity. We found breast cancer cells (MCF10A.NeuT) were capable of transforming normal mammary epithelial cells (MCF10A). The transformed cells exhibited cancerous properties including enhanced proliferation and migration, loss of apical-basal polarity and depolarized acini structure associated with epithelial-mesenchymal transition (EMT). The transformed MCF10A cells displayed distinct EMT characteristics compared to parental cells. We further showed that cancer cell-secreted factors were sufficient to induce cancerous transformation of normal cells. Furthermore, transformed cells were resistant to radiation treatment, providing new insights into mechanisms underlying therapeutic resistance.

Involvement of microRNAs-MMPs-E-cadherin in the migration and invasion of gastric cancer cells infected with Helicobacter pylori

It has been found that Helicobacter pylori （H. pylori）is not only the main cause of gastric cancer, but also closely related to its metastasis. E-cadherin cleavage induced by matrix metalloproteinases (MMPs) plays an important role in the tumor metastasis. In the present study, we investigated the role of microRNAs-MMPs-E-cadherin in migration and invasion of gastric cancer cells treated with H. pylori. The results showed that H. pylori induced migration and invasion of SGC-7901 cells with a down-regulation of E-cadherin expression, which were abolished by MMPs knock down, E-cadherin overexpression, mimics of miR128 and miR148a. MiR128/miR148a inhibitors restored MMP-3/MMP-7 expression, down-regulated E-cadherin level, and accelerated cellular migration and invasion. This study suggests that H. pylori induces migration and invasion of gastric cancer cells through reduction of E-cadherin function by activation of MMP-3, - 7. The present results also suggest that the activated MMPs/E-cadherin pathway is related with down-regulation of miR128/miR148a in the human gastric cancer cells infected with H. pylori.

Microfabrication-Based Three-Dimensional (3-D) Extracellular Matrix Microenvironments for Cancer and Other Diseases

Exploring the complicated development of tumors and metastases needs a deep understanding of the physical and biological interactions between cancer cells and their surrounding microenvironments. One of the major challenges is the ability to mimic the complex 3-D tissue microenvironment that particularly influences cell proliferation, migration, invasion, and apoptosis in relation to the extracellular matrix (ECM). Traditional cell culture is unable to create 3-D cell scaffolds resembling tissue complexity and functions, and, in the past, many efforts were made to realize the goal of obtaining cell clusters in hydrogels. However, the available methods still lack a precise control of cell external microenvironments. Recently, the rapid development of microfabrication techniques, such as 3-D printing, microfluidics, and photochemistry, has offered great advantages in reconstructing 3-D controllable cancer cell microenvironments in vitro. Consequently, various biofunctionalized hydrogels have become the ideal candidates to help the researchers acquire some new insights into various diseases. Our review will discuss some important studies and the latest progress regarding the above approaches for the production of 3-D ECM structures for cancer and other diseases. Especially, we will focus on new discoveries regarding the impact of the ECM on different aspects of cancer metastasis, e.g., collective invasion, enhanced intravasation by stress and aligned collagen fibers, angiogenesis regulation, as well as on drug screening.

Role of WNT/β-Catenin Pathway as Potential Prognostic and Predictive Factors in Renal Cell Cancer Patients Treated With Everolimus in the Second and Subsequent Lines

BACKGROUND

The aim of the present study was to search for predictive and prognostic factors in patients with metastatic renal cell carcinoma (mRCC) treated with everolimus among the components of the WNT/β-catenin pathway.

PATIENTS AND METHODS

In a prospective, single-arm, phase II study, patients with mRCC received everolimus (10 mg/d) in a 30-day cycle. We performed a prospectively planned evaluation of the potential biomarkers of the WNT/β-catenin pathway.

RESULTS

The serum level of soluble E-cadherin (sE-cadherin) in patients with RCC was significantly greater than that in the controls (71.62 ± 22.28 pg/mL vs. 54.26 ± 10.317 pg/mL; P = .0069). After 2 cycles of everolimus therapy, we observed a significance increase in sE-cadherin (from 71.81 ± 21.18 pg/mL to 77.50 ± 28.212 pg/mL; P = .0151). The Dickkopf-1 protein levels in the study and control groups were not significantly different (P = .2135). The favorable independent predictors for everolimus therapy were normal lactate dehydrogenase level before treatment (hazard ratio [HR], 0.52; 95% confidence interval [CI], 0.28-0.98; P = .0443) and low sE-cadherin level (HR, 0.54; 95% CI, 0.29-0.98; P = .0422). On multivariate analysis, we observed that worse overall survival was seen in patients with a lower regression coefficient of sE-cadherin after 2 cycles of treatment (HR, 2.60; 95% CI, 1.23-5.52; P = .0128), an increased corrected calcium level (HR, 3.09; 95% CI, 1.21-7.88; P = .0180), and an increased lactate dehydrogenase level before treatment (HR, 1.98; 95% CI, 1.02-3.83; P = .0426).

CONCLUSION

WNT/β-catenin component expression in patients with mRCC had no effect on progression-free survival or overall survival. However, we found that the sE-cadherin level might interact with response to everolimus therapy, although confirmation in future studies is needed.

TGF-β1 gene silencing can enhances the sensitivity of breast cancer to cisplatin partially by restraining the occurrence of EMT

Breast cancer is one of the most common gynecological malignant tumors, the main reason of treatment failure is distant metastasis and local recurrence. TGF-β1 as a versatile polypeptide molecule plays an important role in inducing EMT to promote tumor invasion and metastasis. This study aims to investigate the effect of TGF-β1 on cisplatin (DDP) inhibiting the proliferation, migration and invasion of breast cancer and its correlation with EMT. TGF-β1 siRNA were transfected into MCF-7 cells. The cell morphology, proliferation, migration and invasion ability changes were detected by inverted microscope, clone formation assay, cell adhesion assay and Transwell Chamber Invasion. The expression of E-cadherin, vimentin, α-SMA were detected by Western blot. The results showed that TGF-β1 siRNA were transfected into MCF-7 cells successfully (P<0.05). The inhibitory activity of cisplatin on cell proliferation, migration and invasion of breast cancer were significantly enhanced after TGF-β1 siRNA transfection (P<0.05). The expression of E-cadherin was up-regulated, and vimentin and α-SMA were down-regulated with TGF-β1 siRNA transfection (P<0.05). Therefore, we concluded that TGF-β1 gene silencing can enhance the sensitivity of breast cancer to cisplatin on proliferation, migration and invasion partially by restraining the occurrence of EMT.

A novel 3-D bio-microfluidic system mimicking in vivo heterogeneous tumour microstructures reveals complex tumour-stroma interactions

A 3-D microfluidic system consisting of microchamber arrays embedded in a collagen hydrogel with tuneable biochemical gradients that mimics the tumour microenvironment of mammary glands was constructed for the investigation on the interactions between invasive breast cancer cells and stromal cells. The hollow microchambers in collagen provide a very similar 3-D environment to that in vivo that regulates collective cellular dynamics and behaviour, while the microfluidic channels surrounding the collagen microchamber arrays allow one to impose complex concentration gradients of specific biological molecules or drugs. We found that breast epithelial cells (MCF-10A) seeded in the microchambers formed lumen-like structures similar to those in epithelial layers. When MCF-10A cells were co-cultured with invasive breast cancer cells (MDA-MB-231), the formation of lumen-like structures in the microchambers was inhibited, indicating the capability of cancer cells to disrupt the structures formed by surrounding cells for further invasion and metastasis. Subsequent mechanism studies showed that down regulation of E-cad expression due to MMPs produced by the cancer cells plays a dominant role in determining the cellular behaviour. Our microfluidic system offers a robust platform for high throughput studies that aim to understand combinatorial effects of multiple biochemical and microenvironmental factors.

ATM mutations and E-cadherin expression define sensitivity to EGFR-targeted therapy in colorectal cancer

EGFR-targeted therapy is a key treatment approach in patients with RAS wildtype metastatic colorectal cancers (CRC). Still, also RAS wildtype CRC may be resistant to EGFR-targeted therapy, with few predictive markers available for improved stratification of patients. Here, we investigated response of 7 CRC cell lines (Caco-2, DLD1, HCT116, HT29, LS174T, RKO, SW480) to Cetuximab and correlated this to NGS-based mutation profiles, EGFR promoter methylation and EGFR expression status as well as to E-cadherin expression. Moreover, tissue specimens of primary and/or recurrent tumors as well as liver and/or lung metastases of 25 CRC patients having received Cetuximab and/or Panitumumab were examined for the same molecular markers. In vitro and in situ analyses showed that EGFR promoter methylation and EGFR expression as well as the MSI and or CIMP-type status did not guide treatment responses. In fact, EGFR-targeted treatment responses were also observed in RAS exon 2 p.G13 mutated CRC cell lines or CRC cases and were further linked to PIK3CA exon 9 mutations. In contrast, non-response to EGFR-targeted treatment was associated with ATM mutations and low E-cadherin expression. Moreover, down-regulation of E-cadherin by siRNA in otherwise Cetuximab responding E-cadherin positive cells abrogated their response. Hence, we here identify ATM and E-cadherin expression as potential novel supportive predictive markers for EGFR-targeted therapy.

Proteases Revisited: Roles and Therapeutic Implications in Fibrosis

Proteases target many substrates, triggering changes in distinct biological processes correlated with cell migration, EMT/EndMT and fibrosis. Extracellular protease activity, demonstrated by secreted and membrane-bound protease forms, leads to ECM degradation, activation of other proteases (i.e., proteolysis of nonactive zymogens), decomposition of cell-cell junctions, release of sequestered growth factors (TGF-β and VEGF), activation of signal proteins and receptors, degradation of inflammatory inhibitors or inflammation-related proteins, and changes in cell mechanosensing and motility. Intracellular proteases, mainly caspases and cathepsins, modulate lysosome activity and signal transduction pathways. Herein, we discuss the current knowledge on the multidimensional impact of proteases on the development of fibrosis.

Cadherin-6B proteolysis promotes the neural crest cell epithelial-to-mesenchymal transition through transcriptional regulation

Cadherin proteolysis reduces cell–cell adhesion and generates cleavage products that could possess independent functions. Here, Schiffmacher et al. reveal that the intracellular C-terminal fragment generated by Cadherin-6B proteolysis promotes chick cranial neural crest cell EMT through positive transcriptional feedback into the neural crest gene regulatory network.

During epithelial-to-mesenchymal transitions (EMTs), cells disassemble cadherin-based junctions to segregate from the epithelia. Chick premigratory cranial neural crest cells reduce Cadherin-6B (Cad6B) levels through several mechanisms, including proteolysis, to permit their EMT and migration. Serial processing of Cad6B by a disintegrin and metalloproteinase (ADAM) proteins and γ-secretase generates intracellular C-terminal fragments (CTF2s) that could acquire additional functions. Here we report that Cad6B CTF2 possesses a novel pro-EMT role by up-regulating EMT effector genes in vivo. After proteolysis, CTF2 remains associated with β-catenin, which stabilizes and redistributes both proteins to the cytosol and nucleus, leading to up-regulation of β-catenin, CyclinD1, Snail2, and Snail2 promoter-based GFP expression in vivo. A CTF2 β-catenin–binding mutant, however, fails to alter gene expression, indicating that CTF2 modulates β-catenin–responsive EMT effector genes. Notably, CTF2 association with the endogenous Snail2 promoter in the neural crest is β-catenin dependent. Collectively, our data reveal how Cad6B proteolysis orchestrates multiple pro-EMT regulatory inputs, including CTF2-mediated up-regulation of the Cad6B repressor Snail2, to ensure proper cranial neural crest EMT.

Beyond a tumor suppressor: Soluble E-cadherin promotes the progression of cancer

E-cadherin (E-cad) plays important roles in tumorigenesis as well as in tumor progression, invasion and metastasis. This protein exists in two forms: a membrane-tethered form and a soluble form. Full-length E-cad is membrane tethered. As a type I transmembrane glycoprotein, E-cad mainly mediates adherens junctions between cells and is involved in maintaining the normal structure of epithelial tissues. Soluble E-cad (sE-cad) is the extracellular fragment of the protein that is cleaved from the membrane after proteolysis of full-length E-cad. The production of sE-cad undermines adherens junctions, causing a reduction in cell aggregation capacity; furthermore, sE-cad can diffuse into the extracellular environment and the blood. As a paracrine/autocrine signaling molecule, sE-cad activates or inhibits multiple signaling pathways and participates in the progression of various types of cancer, such as breast cancer, ovarian cancer, and lung cancer, by promoting invasion and metastasis. This article briefly reviews the role of sE-cad in tumorigenesis and tumor progression and its significance in clinical therapeutics.