MgCl2 and ZnCl2 promote human umbilical vein endothelial cell migration and invasion and stimulate epithelial-mesenchymal transition via the Wnt/β-catenin pathway

Subcutaneous device-free islet transplantation

Diabetes mellitus is a chronic metabolic disease, characterized by high blood sugar levels; it affects more than 500 million individuals worldwide. Type 1 diabetes mellitus (T1DM) is results from insufficient insulin secretion by islets; its treatment requires lifelong use of insulin injections, which leads to a large economic burden on patients. Islet transplantation may be a promising effective treatment for T1DM. Clinically, this process currently involves directly infusing islet cells into the hepatic portal vein; however, transplantation at this site often elicits immediate blood-mediated inflammatory and acute immune responses. Subcutaneous islet transplantation is an attractive alternative to islet transplantation because it is simpler, demonstrates lower surgical complication risks, and enables graft monitoring and removal. In this article, we review the current methods of subcutaneous device-free islet transplantation. Recent subcutaneous islet transplantation techniques with high success rate have involved the use of bioengineering technology and biomaterial cotransplantation-including cell and cell growth factor co-transplantation and hydrogel- or simulated extracellular matrix-wrapped subcutaneous co-transplantation. In general, current subcutaneous device-free islet transplantation modalities can simplify the surgical process and improve the posttransplantation graft survival rate, thus aiding effective T1DM management.

ARID1A downregulation promotes cell proliferation and migration of colon cancer via VIM activation and CDH1 suppression

According to our prior findings, ARID1A expression is decreased in colon cancer, which has a poor prognosis. In this study, we investigated the ARID1A-VIM/CDH1 signalling axis's role in colon cancer proliferation and migration. The differentially expressed genes in cells that might be controlled by ARID1A were discovered by a database screening for ARID1A knockout. qPCR was used to analyse ARID1A and EMT markers expression levels in colon cancer. We utilized siRNA RID1A to explore the influence of ARID1A silencing on EMT in CRC cells. The function of ARID1A in the colon was investigated utilizing the wound healing, transwell and CCK-8 WST- assays. The molecular mechanism by which ARID1A regulates VIM and CDH1 was elucidated using chip-qPCR. Numerous genes involved in EMT were dysregulated in the absence of ARID1A. VIM expression increased in cells lacking ARID1A expression and vice versa. Many COAD samples with high ARID1A mRNA expression had low VIM mRNA expression, despite the relevance. CDH1 gene was positively correlated with ARID1A. Moreover, siRNA-ARID1A-transfected cells accelerated cell migration and invasion and increased cell proliferation rate in vitro. Chip-qPCR analysis showed that ARID1A binds to the promoters of both genes and changes their expression in colon cancer. ARID1A inactivation is associated with VIM activation and CDH1 suppression, which might serve as crucial molecules influencing COAD prognosis, accelerate tumour progression, and shorten patients' survival time, and promote metastases of COAD. Thus, depletion of ARID1A can be therapeutically exploited by targeting downstream effects to improve cancer treatment-related outcomes.

Magnesium-Assisted Cisplatin Inhibits Bladder Cancer Cell Survival by Modulating Wnt/β-Catenin Signaling Pathway

Magnesium, an essential mineral micronutrient, plays a role in the activation of various transporters and enzymes. The present study aimed to investigate the possibility of applying magnesium to enhance the efficacy of cisplatin which is still ranked as one of the major chemotherapeutic drugs for bladder cancer patients. Results showed that the survival rate and colony formation of bladder cancer cells were reduced by combinatorial treatment with cisplatin and magnesium chloride (MgCl₂). The proportion of apoptotic cells was also increased in UC3 bladder cancer cells treated with a combination of cisplatin and MgCl₂. Most importantly, a marked decrease in nuclear β-catenin was observed in cells that received cisplatin treatment. In addition, the nuclear β-catenin in cisplatin treated cells was further down-regulated by supplementing MgCl₂. 6-bromoindirubin-3′-oxime (BIO), an inhibitor of glycogen synthase kinase-3 (GSK-3) that activates the Wnt/β-catenin signaling pathway by modulating β-catenin activity, was thus applied to further exploit the role of this signaling pathway in magnesium aided cancer treatment. The survival rate of bladder cancer cells was decreased by BIO treatment at concentrations of 1.0, 2.5 and 5.0 μM accompanied by increased β-catenin expression. However, the expression of β-catenin in MgCl₂-treated cells was lower than in untreated cells under the same BIO concentration. The expression of cleaved caspase-3, cleaved caspase-9 and microtubule-associated protein 1 light chain 3- II (LC3-II) was highest in cells treated with MgCl₂ and 5.0 μM BIO among the examined groups. Our findings reveal that magnesium could contribute to cisplatin-based chemotherapy by moderately regulating the Wnt/β-catenin signaling pathway.

Controlled co-delivery system of magnesium and lanthanum ions for vascularized bone regeneration

For craniofacial bone regeneration, how to promote vascularized bone regeneration is still a significant problem, and the controlled release of trace elements vital to osteogenesis has attracted attention. In this study, an ion co-delivery system was developed to promote angiogenesis and osteogenesis. Magnesium ions (Mg²⁺) and lanthanum ions (La³⁺) were selected as biosignal molecules because Mg²⁺can promote angiogenesis and both of them can enhance bone formation. Microspheres made of poly(lactide-co-glycolide) were applied to load La₂(CO₃)₃, which was embedded into a MgO/MgCO₃-loaded cryogel made of photocrosslinkable gelatin methacryloyl to enable co-delivery of Mg²⁺and La³⁺. Evaluations of angiogenesis and osteogenesis were conducted via bothin vitrocell culture using human bone marrow mesenchymal stromal cells andin vivoimplantation using a rat model with calvarial defect (5 mm in diameter). Compared to systems releasing only Mg²⁺or La³⁺, the combination system demonstrated more significant effects on blood vessels formation, thereby promoting the regeneration of vascularized bone tissue. At 8 weeks post-implantation, the new bone volume/total bone volume ratio reached a value of 40.1 ± 0.9%. In summary, a properly designed scaffold system with the capacity to release ions of different bioactivities in a desired pattern can be a promising strategy to meet vascularized bone regeneration requirements.

COL4A1, negatively regulated by XPD and miR-29a-3p, promotes cell proliferation, migration, invasion and epithelial-mesenchymal transition in liver cancer cells

OBJECTIVE

Collagen type IV alpha 1 (COL4A1) exerts tumor-promoting functions in several tumors. However, its role in liver cancer remains not fully understood. Hence, this study aims to investigate the role of COL4A1 in regulating liver cancer cell behaviors and to validate its upstream regulatory mechanism.

METHODS

Expression of xeroderma pigmentosum D (XPD) and COL4A1 was examined by qRT-PCR and western blot. Cell proliferation, migration, and invasion were evaluated. The protein levels of N-cadherin, vimentin, and E-cadherin were determined by western blot to evaluate epithelial-mesenchymal transition (EMT). The interaction between miR-29a-3p and COL4A1 was analyzed by luciferase reporter assay.

RESULTS

COL4A1 overexpression significantly promoted cell proliferation, migration, invasion, and EMT in Hep3B cells. In contrast, COL4A1 silencing yielded the opposite effects in HepG2 cells. Expression of COL4A1 was increased, whereas expression of XPD and miR-29a-3p was decreased in HCC tissues compared to controls. COL4A1 mRNA level was negatively correlated with expression of XPD and miR-29a-3p in HCC tissues. Furthermore, XPD silencing-mediated up-regulation of COL4A1 expression was attenuated by miR-29a-3p mimic. Moreover, miR-29a-3p mimic inhibited Hep3B cell proliferation, migration, and invasion by directly targeting COL4A1.

CONCLUSION

COL4A1 is negatively regulated by XPD-miR-29a-3p axis and promotes liver cancer progression in vitro.

WNT1, a target of miR-34a, promotes cervical squamous cell carcinoma proliferation and invasion by induction of an E-P cadherin switch via the WNT/β-catenin pathway

Purpose

Persistent infection with high-risk human papillomavirus (HR-HPV) is thought to play a prominent role in the initiation and progression of almost all cases of cervical cancer. Previously, we and others found that microRNA 34a (miR-34a) may be regulated by HR-HPV E6 to contribute to the development of cervical cancer. Here, we aimed to identify the oncogenic potential and clinical significance of a known miR-34a target, WNT1, in cervical squamous cell carcinoma (SCC) development and to investigate the associated mechanisms underlying cervical SCC cell proliferation and invasion.

Methods

WNT1 and miR-34a expression levels were assessed in primary cervical lesions using immunohistochemistry and qRT-PCR, respectively. The cellular effects and the expression of its associated genes were examined in cervical SCC-derived Siha and Caski cells after siRNA-WNT1 (downregulation) or miR-34a mimic (upregulation) treatment. A cervical SCC xenograft mouse model was used to investigate the in vivo effects of miR-34a overexpression. HPV-16 E6/E7 expression was inhibited by gene promoter siRNA targeting, after which the levels of miR-34a and WNT1 were examined.

Results

WNT1 protein upregulation was found to be associated with a poor prognosis in cervical SCC patients. In vitro assays in Siha and Caski cells revealed that WNT1 downregulation decreased cell proliferation and invasion, inhibited WNT/β-catenin activation and affected the expression of E-cadherin and P-cadherin. MiR-34a upregulation resulted in decreased WNT1 expression. An inverse correlation between miR-34a and WNT1 expression was also observed in primary cervical SCC tissues. In addition, we found that MiR-34a could regulate an E-cadherin to P-cadherin switch (E-P cadherin switch) to inhibit cell proliferation and tumorigenesis in vitro and in vivo via inactivation of the WNT1/β-catenin pathway. Finally, we found that decreased HPV-16 E6/E7 expression resulted in miR-34a upregulation and WNT1 downregulation in Siha and Caski cells.

Conclusions

From our results we conclude that WNT1, as a target of miR-34a, can promote cervical SCC cell proliferation and invasion by induction of an E-P cadherin switch via the WNT1/β-catenin pathway. Our results may provide new options for the treatment of patients with cervical SCC.

Electronic supplementary material

The online version of this article (10.1007/s13402-020-00506-8) contains supplementary material, which is available to authorized users.

VEGF-Modified PVA/Silicone Nanofibers Enhance Islet Function Transplanted in Subcutaneous Site Followed by Device-Less Procedure

INTRODUCTION

As heterologous islets or islet-like stem cells become optional sources for islet transplantation, the subcutaneous site appears to be an acceptable replacement of the intrahepatic site due to its graft retrievability. The device-less (DL) procedure improves the feasibility; however, some limitations such as fibrotic overgrowth or immunodeficiency still exist. Nanofibers could mimic the extracellular matrix to improve the vitality of transplanted islets. Therefore, we designed a vascular endothelial growth factor (VEGF)-modified polyvinyl alcohol (PVA)/silicone nanofiber (SiO2-VEGF) to optimize the DL procedure.

METHODS

SiO2-VEGF nanofibers were designed by nano-spinning and characterized the physical-chemical properties before subcutaneous islet transplantation. Cell viability, vessel formation, and glucose-stimulated insulin secretion were tested in vitro to ensure biocompatibility; and blood glucose level (BGL), transplanted islet function, and epithelial-mesenchymal transition (EMT)-related biomarker expression were analyzed in vivo.

RESULTS

The intensity of inflammatory reaction induced by SiO2 nanofibers was between nylon and silicone, which did not bring out excessive fibrosis. The vascularization could be enhanced by VEGF functionalization both in vitro and in vivo. The BGL control was better in the DL combined with SiO2-VEGF group. The percentage of recipients that achieved normoglycemia was higher and earlier (71% at day 57), and the intraperitoneal glucose tolerance test (IPGTT) also confirmed better islet function. The expressions of vimentin, α-SMA, and twist-1 were upregulated, which indicated that SiO2-VEGF nanofibers might promote islet function by regulating the EMT pathway.

DISCUSSION

In summary, our new SiO2-VEGF combined with DL procedure might improve the feasibility of subcutaneous islet transplantation for clinical application.

The role of Wnt signaling in the healing myocardium: a focus on cell specificity

Various cell types are involved in the healing process after myocardial infarction (MI). Besides cardiac resident cells (such as cardiomyocytes, fibroblasts and endothelial cells) already present at the lesion site, a massive influx of leukocytes (mainly monocytes and neutrophils) is observed within hours after the ischemic event. So far, little is known about modes of interaction of these cells. Wnt signaling is an evolutionary conserved signaling cassette known to play an important role in cell-cell communication. While the overall reactivation of Wnt signaling upon ischemic injury is well described, the precise expression pattern of Wnt proteins, however, is far from understood. We here describe known Wnt components that partake in MI healing and differentiate cell-specific aspects. The secretion of Wnt proteins and their antagonists in the context of cardiac inflammation after MI appear to be tightly regulated in a spatial-temporal manner. Overall, we aim to stress the importance of elucidating not only Wnt component-specific aspects, but also their sometimes contradicting effects in different target cells. A better understanding of Wnt signaling in MI healing may eventually lead to the development of successful therapeutic approaches in an often considered "un-druggable" pathway.