Characterization of matrix metalloproteinase-2 and -9, ADAM-10 and N-cadherin expression in human glioblastoma multiforme

Glioblastoma U-87 cell electrotaxis is hindered by doxycycline with a concomitant reduction in the matrix metallopeptidase-9 expression

Electric fields (EF) play an essential role in cancer cell migration. Numerous cancer cell types exhibit electrotaxis under direct current electric fields (dcEF) of physiological electric field strength (EFs). This study investigated the effects of doxycycline on the electrotactic responses of U87 cells. After EF stimulation, U87 cells migrated toward the cathode, whereas doxycycline-treated U87 cells exhibited enhanced cell mobility but hindered cathodal migration. We further investigated the expression of the metastasis-correlated proteins matrix metallopeptidase-2 (MMP-2) and MMP-9 in U87 cells. The levels of MMP-2 in the cells were not altered under EF or doxycycline stimulation. In contrast, the EF stimulation greatly enhanced the levels of MMP-9 and then repressed in doxycycline-cotreated cells, accompanied by reduced cathodal migration. Our results demonstrated that an antibiotic at a non-toxic concentration could suppress the enhanced cell migration accelerated by EF of physiological strength. This finding may be applied as an anti-metastatic treatment for cancers.

Rosacea and Its Association With Malignancy: Systematic Review

BACKGROUND

Rosacea is a chronic inflammatory skin condition that predominantly manifests as facial flushing, irritation, and acne. Rosacea and cancer are thought to be linked by the commonality of inflammatory and immune response dysfunction. Studies that have looked into this possible association have reported mixed results.

OBJECTIVE

Given the conflicting literature on this topic, our study sought to evaluate the overall association between rosacea and several cancers commonly investigated in the literature.

METHODS

A systematic review was conducted using the Cochrane, PubMed, Embase, and Ovid databases. Studies were screened independently for inclusion of rosacea and glioma and breast, thyroid, hepatic, or skin cancers. Using information from the articles, rosacea and each cancer were categorized as having a positive, negative, or unclear association.

RESULTS

Our systematic review included 39 full-text studies that investigated the association between rosacea and various malignancies. Among the malignancies of concern, 41% (16/39) of the studies reported an association with basal cell carcinoma, with 2 cohorts revealing an adjusted risk ratio (RR) of 1.50 (95% CI 1.35-1.67) and 0.72 (95% CI 0.56-0.93). In total, 33% (13/39) of the studies reported an association with squamous cell carcinoma, with 2 cohorts revealing an adjusted RR of 1.4 (95% CI 1.02-1.93) and 1.30 (95% CI 0.90-1.88). A total of 8% (3/39) of the studies reported an association between breast cancer and melanoma, with breast cancer cohorts revealing an adjusted RR of 8.453 (95% CI 1.638-43.606), 1.03 (95% CI 0.89-1.20), and 1.36 (95% CI 1.18-1.58) and melanoma cohorts revealing an adjusted RR of 1.10 (95% CI 0.95-1.27), 0.63 (95% CI 0.47-0.85), and 0.96 (95% CI 0.57-1.62). A total of 5% (2/39) of the studies reported an association among nonmelanoma skin cancers, hepatic cancer, and thyroid carcinomas, with nonmelanoma skin cancer cohorts revealing an adjusted RR of 1.36 (95% CI 1.26-1.47) and 2.66 (95% CI 1.53-4.61), hepatic cancer cohorts revealing an adjusted RR of 1.42 (95% CI 1.06-1.90) and 1.32 (95% CI 0.89-1.95), and thyroid carcinoma cohorts revealing an adjusted RR of 1.06 (95% CI 0.68-1.65) and 1.59 (95% CI 1.07-2.36). Only 1 cohort reported an association with glioma, revealing an adjusted RR of 1.36 (95% CI 1.18-1.58). According to our review, patients with rosacea were statistically more likely to have nonmelanoma skin cancers, breast cancer, and glioma. Rosacea was not found to be substantially associated with melanoma. The associations between rosacea and hepatic and thyroid cancers were unclear because of conflicting results.

CONCLUSIONS

The current literature shows that rosacea is significantly associated with increased odds of nonmelanoma skin cancers, glioma, and breast cancer. Rosacea does not appear to be associated with melanoma. Further studies should be conducted to clarify the association between thyroid and hepatic cancers and rosacea.

Invadopodia associated Thrombospondin-1 contributes to a post-therapy pro-invasive response in glioblastoma cells

A critical challenge in the treatment of glioblastoma (GBM) is its highly invasive nature which promotes cell migration throughout the brain and hinders surgical resection and effective drug delivery. GBM cells demonstrate augmented invasive capabilities following exposure to the current gold standard treatment of radiotherapy (RT) and concomitant and adjuvant temozolomide (TMZ), resulting in rapid disease recurrence. Elucidating the mechanisms employed by post-treatment invasive GBM cells is critical to the development of more effective therapies. In this study, we utilized a Nanostring® Cancer Progression gene expression panel to identify candidate genes that may be involved in enhanced GBM cell invasion after treatment with clinically relevant doses of RT/TMZ. Our findings identified thrombospondin-1 (THBS1) as a pro-invasive gene that is upregulated in these cells. Immunofluorescence staining revealed that THBS1 localised within functional matrix-degrading invadopodia that formed on the surface of GBM cells. Furthermore, overexpression of THBS1 resulted in enhanced GBM cell migration and secretion of MMP-2, which was reduced with silencing of THBS1. The preliminary data demonstrates that THBS1 is associated with invadopodia in GBM cells and is likely involved in the invadopodia-mediated invasive process in GBM cells exposed to RT/TMZ treatment. Therapeutic inhibition of THBS1-mediated invadopodia activity, which facilitates GBM cell invasion, should be further investigated as a treatment for GBM.

Cellular Conversations in Glioblastoma Progression, Diagnosis and Treatment

Glioblastoma (GBM) is the most frequent malignancy among primary brain tumors in adults and one of the worst 5-year survival rates (< 7%) among all human cancers. Till now, treatments that target particular cell or intracellular metabolism have not improved patients' survival. GBM recruits healthy brain cells and subverts their processes to create a microenvironment that contributes to supporting tumor progression. This microenvironment encompasses a complex network in which malignant cells interact with each other and with normal and immune cells to promote tumor proliferation, angiogenesis, metastasis, immune suppression, and treatment resistance. Communication can be direct via cell-to-cell contact, mainly through adhesion molecules, tunneling nanotubes, gap junctions, or indirect by conventional paracrine signaling by cytokine, neurotransmitter, and extracellular vesicles. Understanding these communication routes could open up new avenues for the treatment of this lethal tumor. Hence, therapeutic approaches based on glioma cells` communication have recently drawn attention. This review summarizes recent findings on the crosstalk between glioblastoma cells and their tumor microenvironment, and the impact of this conversation on glioblastoma progression. We also discuss the mechanism of communication of glioma cells and their importance as therapeutic targets and diagnostic and prognostic biomarkers. Overall, understanding the biological mechanism of specific interactions in the tumor microenvironment may help in predicting patient prognosis and developing novel therapeutic strategies to target GBM.

Tetraspanin-29 activates Notch signaling by interacting with ADAM10 to enhance its activity in colorectal cancer

ADAM10 acts upstream of Notch signaling and plays oncogenic roles in various cancers. Tetraspanin family proteins regulate ADAM10 trafficking and activity. Here, we aimed to investigate whether and how tetraspanin-29 modulates ADAM10 in colorectal cancer (CRC). We found that ADAM10 expression was upregulated in CRC tissues and this was cross-validated in the TCGA COAD data set. The ADAM10 protein level and its α-secretase activity were enhanced in CRC cell lines compared with control cell lines. Co-immunoprecipitation showed ADAM10 interacted with tetraspanin-29 in the LoVo cell line. Tetraspanin-29 knockdown reduced the cell surface trafficking and α-secretase activity of ADAM10. In addition, tetraspanin-29 knockdown inhibited Notch activity in a luciferase reporter assay and reduced the levels of cleaved Notch1 and Notch target genes such as HES2, c-MYC, and cyclin D3. Consistently, tetraspanin-29 overexpression increased cleaved Notch1 and this effect was blocked by ADAM10 inhibitors. The TCGA COAD data set confirmed the positive correlations of tetraspanin-29 with HES2, c-MYC, and cyclin D3. Thus, the tetraspanin-29/ADAM10/Notch pathway plays an important role in CRC.

Crosstalk between PI3K/AKT/mTOR and WNT/β-Catenin signaling in GBM - Could combination therapy checkmate the collusion?

Glioblastoma multiforme is one of the calamitous primary glial brain tumors with extensive heterogeneity at cellular and molecular levels. While maximal surgical resection trailed by radio and chemotherapy employing temozolomide remains the gold-standard treatment for malignant glioma patients, the overall prognosis remains dismal and there exists an unmet need for effective therapeutic strategies. In this context, we hypothesize that proper understanding of signaling pathways responsible for glioblastoma multiforme proliferation would be the first trump card while searching for novel targeted therapies. Among the pathways aberrantly activated, PI3K/AKT/mTOR is the most significant pathway, that is clinically implicated in malignancies such as high-grade glioma. Further, the WNT/β-Catenin cascade is well-implicated in several malignancies, while its role in regulating glioma pathogenesis has only emerged recently. Nevertheless, oncogenic activation of both these pathways is a frequent event in malignant glioma that facilitates tumor proliferation, stemness and chemo-resistance. Recently, it has been reported that the cross-talk of PI3K/AKT/mTOR pathway with multiple signaling pathways could promote glioma progression and reduce the sensitivity of glioma cells to the standard therapy. However, very few studies had focused on the relationship between PI3K/AKT/mTOR and WNT/β-Catenin pathways in glioblastoma multiforme. Interestingly, in homeostatic and pathologic circumstances, both these pathways depict fine modulation and are connected at multiple levels by upstream and downstream effectors. Thus, gaining deep insights on the collusion between these pathways would help in discovering unique therapeutic targets for glioblastoma multiforme management. Hence, the current review aims to address, "the importance of inter-play between PI3K/AKT/mTOR and WNT/β-Catenin pathways", and put forward, "the possibility of combinatorially targeting them", for glioblastoma multiforme treatment enhancement.

The Metalloprotease-Disintegrin ADAM8 Alters the Tumor Suppressor miR-181a-5p Expression Profile in Glioblastoma Thereby Contributing to Its Aggressiveness

Glioblastoma (GBM) as the most common and aggressive brain tumor is characterized by genetic heterogeneity, invasiveness, radio-/chemoresistance, and occurrence of GBM stem-like cells. The metalloprotease-disintegrin ADAM8 is highly expressed in GBM tumor and immune cells and correlates with poor survival. In GBM, ADAM8 affects intracellular kinase signaling and increases expression levels of osteopontin/SPP1 and matrix metalloproteinase 9 (MMP9) by an unknown mechanism. Here we explored whether microRNA (miRNA) expression levels could be regulators of MMP9 expression in GBM cells expressing ADAM8. Initially, we identified several miRNAs as dysregulated in ADAM8-deficient U87 GBM cells. Among these, the tumor suppressor miR-181a-5p was significantly upregulated in ADAM8 knockout clones. By inhibiting kinase signaling, we found that ADAM8 downregulates expression of miR-181a-5p via activation of signal transducer and activator of transcription 3 (STAT3) and mitogen-activated protein kinase (MAPK) signaling suggesting an ADAM8-dependent silencing of miR-181a-5p. In turn, mimic miR-181a-5p transfection caused decreased cell proliferation and lower MMP9 expression in GBM cells. Furthermore, miR-181a-5p was detected in GBM cell-derived extracellular vesicles (EVs) as well as patient serum-derived EVs. We identified miR-181a-5p downregulating MMP9 expression via targeting the MAPK pathway. Analysis of patient tissue samples (n=22) revealed that in GBM, miR-181a-5p is strongly downregulated compared to ADAM8 and MMP9 mRNA expression, even in localized tumor areas. Taken together, we provide evidence for a functional axis involving ADAM8/miR-181a-5p/MAPK/MMP9 in GBM tumor cells.

Key Role of Astrocytes in Postnatal Brain and Retinal Angiogenesis

Angiogenesis is a key process in various physiological and pathological conditions in the nervous system and in the retina during postnatal life. Although an increasing number of studies have addressed the role of endothelial cells in this event, the astrocytes contribution in angiogenesis has received less attention. This review is focused on the role of astrocytes as a scaffold and in the stabilization of the new blood vessels, through different molecules release, which can modulate the angiogenesis process in the brain and in the retina. Further, differences in the astrocytes phenotype are addressed in glioblastoma, one of the most devastating types of brain cancer, in order to provide potential targets involved in the cross signaling between endothelial cells, astrocytes and glioma cells, that mediate tumor progression and pathological angiogenesis. Given the relevance of astrocytes in angiogenesis in physiological and pathological conditions, future studies are required to better understand the interrelation between endothelial and astrocyte signaling pathways during this process.

Systematic analysis of potential targets of the curcumin analog pentagamavunon-1 (PGV-1) in overcoming resistance of glioblastoma cells to bevacizumab

Background

Glioblastoma is one of the most aggressive and deadliest malignant tumors. Acquired resistance decreases the effectiveness of bevacizumab in glioblastoma treatment and thus increases the mortality rate in patients with glioblastoma. In this study, the potential targets of pentagamavunone-1 (PGV-1), a curcumin analog, were explored as a complementary treatment to bevacizumab in glioblastoma therapy.

Methods

Target prediction, data collection, and analysis were conducted using the similarity ensemble approach (SEA), SwissTargetPrediction, STRING DB, and Gene Expression Omnibus (GEO) datasets. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted using Webgestalt and DAVID, respectively. Hub genes were selected based on the highest degree scores using the CytoHubba. Analysis of genetic alterations and gene expression as well as Kaplan–Meier survival analysis of selected genes were conducted with cBioportal and GEPIA. Immune infiltration correlations between selected genes and immune cells were analyzed with database TIMER 2.0.

Results

We found 374 targets of PGV-1, 1139 differentially expressed genes (DEGs) from bevacizumab-resistant-glioblastoma cells. A Venn diagram analysis using these two sets of data resulted in 21 genes that were identified as potential targets of PGV-1 against bevacizumab resistance (PBR). PBR regulated the metabolism of xenobiotics by cytochrome P450. Seven potential therapeutic PBR, namely GSTM1, AKR1C3, AKR1C4, PTGS2, ADAM10, AKR1B1, and HSD17B110 were found to have genetic alterations in 1.2%–30% of patients with glioblastoma. Analysis using the GEPIA database showed that the mRNA expression of ADAM10, AKR1B1, and HSD17B10 was significantly upregulated in glioblastoma patients. Kaplan–Meier survival analysis showed that only patients with low mRNA expression of AKR1B1 had significantly better overall survival than the patients in the high mRNA group. We also found a correlation between PBR and immune cells and thus revealed the potential of PGV-1 as an immunotherapeutic agent via targeting of PBR.

Conclusion

This study highlighted seven PBR, namely, GSTM1, AKR1C3, AKR1C4, PTGS2, ADAM10, AKR1B1, and HSD17B110. This study also emphasized the potential of PBR as a target for immunotherapy with PGV-1. Further validation of the results of this study is required for the development of PGV-1 as an adjunct to immunotherapy for glioblastoma to counteract bevacizumab resistance.

Antitumor effect of 4MU on glioblastoma cells is mediated by senescence induction and CD44, RHAMM and p-ERK modulation

The extracellular matrix plays a key role in cancer progression. Hyaluronan, the main glycosaminoglycan of the extracellular matrix, has been related to several tumor processes. Hyaluronan acts through the interaction with cell membrane receptors as CD44 and RHAMM and triggers signaling pathways as MEK/ERK. 4-methylumbelliferone (4MU), a well-known hyaluronan synthesis inhibitor, is a promising alternative for cancer therapy. 4MU is a coumarin derivative without adverse effects that has been studied in several tumors. However, little is known about its use in glioblastoma (GBM), the most malignant primary brain tumor in adults. Glioblastoma is characterized by fast growth, migration and tissue invasiveness, and a poor median survival of the patients after treatment. Several reports linked glioblastoma progression with HA levels and even with CD44 and RHAMM expression, as well as MEK/ERK activation. Previously, we showed on a murine GBM cell line that HA enhances GBM migration, while 4MU markedly inhibits it. In this work we showed for the first time, that 4MU decreases cell migration and induces senescence in U251 and LN229 human GBM cell lines. Furthermore, we observed that HA promotes GBM cell migration on both cell lines and that such effects depend on CD44 and RHAMM, as well as MEK/ERK signaling pathway. Interestingly, we observed that the exogenous HA failed to counteract the effects of 4MU, indicating that 4MU effects are independent of HA synthesis inhibition. We found that 4MU decreases total CD44 and RHAMM membrane expression, which could explain the effect of 4MU on cell migration. Furthermore, we observed that 4MU increases the levels of RHAMM inside the cell while decreases the nucleus/cytoplasm relation of p-ERK, associated with 4MU effects on cell proliferation and senescence induction. Overall, 4MU should be considered as a promising therapeutic alternative to improve the outcome of patients with GBM.

Cadherin Expression and EMT: A Focus on Gliomas

Cadherins are calcium-binding proteins with a pivotal role in cell adhesion and tissue homeostasis. The cadherin-dependent mechanisms of cell adhesion and migration are exploited by cancer cells, contributing to tumor invasiveness and dissemination. In particular, cadherin switch is a hallmark of epithelial to mesenchymal transition, a complex development process vastly described in the progression of most epithelial cancers. This is characterized by drastic changes in cell polarity, adhesion, and motility, which lead from an E-cadherin positive differentiated epithelial state into a dedifferentiated mesenchymal-like state, prone to metastization and defined by N-cadherin expression. Although vastly explored in epithelial cancers, how these mechanisms contribute to the pathogenesis of other non-epithelial tumor types is poorly understood. Herein, the current knowledge on cadherin expression in normal development in parallel to tumor pathogenesis is reviewed, focusing on epithelial to mesenchymal transition. Emphasis is taken in the unascertained cadherin expression in CNS tumors, particularly in gliomas, where the potential contribution of an epithelial-to-mesenchymal-like process to glioma genesis and how this may be associated with changes in cadherin expression is discussed.

The role of melatonin in angio-miR-associated inhibition of tumorigenesis and invasion in human glioblastoma tumour spheroids

Micro-RNA (miRNA)-based regulation of hypoxia, angiogenesis and tumour growth provides promising targets for effective therapy in malignant glioblastoma multiforme (GBM). Accumulating evidence suggests a potential role of melatonin in miRNA expression in cancer cells. Despite these findings, the melatonin-miRNA interaction in GBM and the effect of this interaction on GBM tumour development and invasion are not clearly understood. The aim of the present study was to evaluate the effects of melatonin on human GBM tumour spheroid tumorigenesis and invasion in vitro, and to analyse the interaction between 36 angio-miRNAs and the HIF1/VEGF/MMP9 axis, which is known to be associated with the antitumour effect of melatonin. We found that melatonin is able to selectively induce cell death in single-layer U87-MG cells (a GBM cell line) in a dose- and time-dependent manner, as characterized by MTT assay. The use of tumour spheroids and a Matrigel invasion assay revealed that melatonin impairs tumorigenesis, and it significantly reduced both the tumour spheroid area and invasion rate, especially at the 0.5 mM and 1 mM concentrations. This inhibition was accompanied by strong reductions in hypoxia-inducible factor 1-α (HIF1-α) and vascular endothelial growth factor (VEGF) gene expression and protein levels in GBM tumour spheroids. In addition, melatonin significantly reduced the relative gene expression and protein levels of matrix metalloproteinase-9 (MMP-9). This study revealed that six differentially expressed angio-miRs (miR-15b, miR-18a-5p, miR-23a-3p, miR-92a-3p, miR-130a-5p, miR-200b-3p) may play important roles in GBM tumorigenesis and invasion, and all respond to melatonin therapy. Our results suggest that melatonin inhibits tumorigenesis and invasion of human GBM tumour spheroids, possibly by suppressing HIF1-α/VEGF/MMP9 signalling via regulation of angio-miRNAs.

Inhalational Anesthetics Inhibit Neuroglioma Cell Proliferation and Migration via miR-138, -210 and -335

Inhalational anesthetics was previously reported to suppress glioma cell malignancy but underlying mechanisms remain unclear. The present study aims to investigate the effects of sevoflurane and desflurane on glioma cell malignancy changes via microRNA (miRNA) modulation. The cultured H4 cells were exposed to 3.6% sevoflurane or 10.3% desflurane for 2 h. The miR-138, -210 and -335 expression were determined with qRT-PCR. Cell proliferation and migration were assessed with wound healing assay, Ki67 staining and cell count kit 8 (CCK8) assay with/without miR-138/-210/-335 inhibitor transfections. The miRNA downstream proteins, hypoxia inducible factor-1α (HIF-1α) and matrix metalloproteinase 9 (MMP9), were also determined with immunofluorescent staining. Sevoflurane and desflurane exposure to glioma cells inhibited their proliferation and migration. Sevoflurane exposure increased miR-210 expression whereas desflurane exposure upregulated both miR-138 and miR-335 expressions. The administration of inhibitor of miR-138, -210 or -335 inhibited the suppressing effects of sevoflurane or desflurane on cell proliferation and migration, in line with the HIF-1α and MMP9 expression changes. These data indicated that inhalational anesthetics, sevoflurane and desflurane, inhibited glioma cell malignancy via miRNAs upregulation and their downstream effectors, HIF-1α and MMP9, downregulation. The implication of the current study warrants further study.

Emodin protects knee joint cartilage in rats through anti-matrix degradation pathway: An in vitro and in vivo study

AIMS

Osteoarthritis (OA) is a common joint disease and the main cause of disability. We sought to determine the effective concentration of emodin on chondrocytes and to identify the dosage of emodin that induces a comparable therapeutic effect with the COX-2 inhibitor drug, celecoxib that is currently used to treat OA.

MATERIAL AND METHODS

In vitro experiments induced inflammation of chondrocytes by IL-1β, and an osteoarthritis model was established in vivo by cutting rat anterior cruciate ligament. Western Blot, Real-time PCR, HE staining, Safranin O-green staining and immunohistochemistry were performed to detect MMP-3, MMP-13, ADAMTS-4, iNOS and COL2A1 on the chondrocytes or the tibial plateau. The cytokine activity and content in serum of six groups of rats were measured by kit.

RESULTS

It was found that the surface layer of the cartilage was thicker and smoother after the administration of emodin. Tissue expression of MMP-3, MMP-13, ADAMTS-4 and iNOS were significantly (p < 0.05) decreased in chondrocytes and cartilage treated with different doses of emodin, and the content of COL2A1 was reversed. Emodin also significantly decreased the blood levels of COX-2 and PGE2. The effective emodin in vitro was 5 μmol/L, whereas emodin at 80 mg/kg was equivalent to celecoxib in vivo.

CONCLUSION

Emodin reduces the expression of cartilage matrix degradation biomarkers, thereby reducing the degradation of cartilage matrix and protecting the knee joint cartilage. Emodin at 5 μmol/L shows the best concentration to treat chondrocytes, and the protective effect of emodin at 80 mg/kg is comparable to that of celecoxib.

Hippocampal transcriptome deconvolution reveals differences in cell architecture of not demented elderly subjects underwent late-life physical activity

Recent findings demonstrated that physical exercise has a powerful role in improving cognitive function and delaying age-associated neurological decline. However, to date, there is a lack of information regarding the effect of physical activity (PA) on brain cells architecture. In this paper, we hypothesized that PA could play a role in the transcriptional changes of genes that enrich the main cells of central nervous system (CNS). From NCBI, we selected a microarray dataset composed of the human hippocampi (GSE110298) from 23 cognitively intact clinical cases (NDHSs) (aged 87.4 ± 6.3 years) selected to from the Rush Memory and Aging Project (MAP). The significantly expressed genes, obtained comparing hippocampi from subjects who underwent Low Physical Activity (LPA) vs those who performed High Physical Activity (HPA), were overlapped with the main genes enriching the CNS cells, obtained from the public human brain single-cell RNA-sequencing dataset (GSE67835), in order to determine the respective weighted percentages of significantly expression genes modulation (WPSEG). In NDHSs underwent HPA, the WPSEG was higher for Neurons, Dendritic Development, Synaptic transmission genes and Axon Development. In addition, in NDHSs underwent LPA we observed high expression of genes enriching Oligodendrocytes, Microglia, and Endothelial cells. Furthermore, neurogenesis and the decreasing of the T cell-mediated inflammatory process were the two main molecular mechanisms activated in the brains of NDHSs underwent HPA. From our results, it is possible to conclude that, in elderly subjects, the transcriptional profile of CNS cells changes as a function of the PA conducted during life. Performing PA periodically supports the maintenance of the physiological balance of neuronal cells and, consequently, improves the quality of life of the elderly.

Disentangling the therapeutic tactics in GBM: From bench to bedside and beyond

Glioblastoma multiforme (GBM) is one of the most common and malignant form of adult brain tumor with a high mortality rate and dismal prognosis. The present standard treatment comprising surgical resection followed by radiation and chemotherapy using temozolomide can broaden patient's survival to some extent. However, the advantages are not palliative due to the development of resistance to the drug and tumor recurrence following the multimodal treatment approaches due to both intra- and intertumoral heterogeneity of GBM. One of the major contributors to temozolomide resistance is O⁶ -methylguanine-DNA methyltransferase. Furthermore, deficiency of mismatch repair, base excision repair, and cytoprotective autophagy adds to temozolomide obstruction. Rising proof additionally showed that a small population of cells displaying certain stem cell markers, known as glioma stem cells, adds on to the resistance and tumor progression. Collectively, these findings necessitate the discovery of novel therapeutic avenues for treating glioblastoma. As of late, after understanding the pathophysiology and biology of GBM, some novel therapeutic discoveries, such as drug repurposing, targeted molecules, immunotherapies, antimitotic therapies, and microRNAs, have been developed as new potential treatments for glioblastoma. To help illustrate, "what are the mechanisms of resistance to temozolomide" and "what kind of alternative therapeutics can be suggested" with this fatal disease, a detailed history of these has been discussed in this review article, all with a hope to develop an effective treatment strategy for GBM.

Effects of Pacap on Schwann Cells: Focus on Nerve Injury

Schwann cells, the most abundant glial cells of the peripheral nervous system, represent the key players able to supply extracellular microenvironment for axonal regrowth and restoration of myelin sheaths on regenerating axons. Following nerve injury, Schwann cells respond adaptively to damage by acquiring a new phenotype. In particular, some of them localize in the distal stump to form the Bungner band, a regeneration track in the distal site of the injured nerve, whereas others produce cytokines involved in recruitment of macrophages infiltrating into the nerve damaged area for axonal and myelin debris clearance. Several neurotrophic factors, including pituitary adenylyl cyclase-activating peptide (PACAP), promote survival and axonal elongation of injured neurons. The present review summarizes the evidence existing in the literature demonstrating the autocrine and/or paracrine action exerted by PACAP to promote remyelination and ameliorate the peripheral nerve inflammatory response following nerve injury.

MacroH2A1 Immunoexpression in Breast Cancer

MacroH2A1 has two splice isoforms, macroH2A1.1 and macroH2A1.2, that have been studied in several form of cancer. In the literature there are not many scientific papers dealing with the role of macroH2A1 in breast cancer. Breast cancer is the most frequent form of malignancy in females. It tend to metastasize to the bone in ~70% of patients. Despite treatment, new bone metastases will still occur in 30–50% of cases with advanced disease. Overall 5-year survival after the diagnosis of bone metastasis is ~20%. Osteoclasts and osteoblasts of the bone microenvironment are engaged by soluble factors released by neoplastic cells, resulting in bone matrix breakdown. This malfunction enhances the proliferation of the cancer cells, creating a vicious cycle. We investigated immunohistochemical expression of macroH2A1 in primitive breast cancer, focusing on the comparison of metastatic and non-metastatic cases. Furthermore, the immunohistochemical expression of macroH2A1 has been evaluated both in all cases of nodal metastases and in distant metastases. Our data demonstrated that macroH2A1 expression was higher expressed in metastatic breast cancer (77%) vs. non-metastatic breast cancer (32%). Also in analyzed metastases cases, a high macroH2A1 expression was detected: 85 and 80% in nodal and distant metastases cases, respectively. These results supported the fact that macroH2A1 is more highly expressed in breast cancer with worst prognosis.

Dual-specificity phosphatase (DUSP6) in human glioblastoma: epithelial-to-mesenchymal transition (EMT) involvement

Objective

Glioblastoma (GBM) is the most aggressive and common form of primary brain cancer. Survival is poor and improved treatment options are urgently needed. Dual specificity phosphatase-6 (DUSP6) is actively involved in oncogenesis showing unexpected tumor-promoting properties in human glioblastoma, contributing to the development and expression of the full malignant and invasive phenotype. The purpose of this study was to assess if DUSP6 activates epithelial-to-mesenchymal transition (EMT) in glioblastoma and its connection with the invasive capacity.

Results

We found high levels of transcripts mRNA by qPCR analysis in a panel of primary GBM compared to adult or fetal normal tissues. At translational levels, these data correlate with high protein expression and long half-life values by cycloheximide-chase assay in immunoblot experiments. Next, we demonstrate that DUSP6 gene is involved in epithelial-to-mesenchymal transition (EMT) in GBM by immunoblot characterization of the mesenchymal and epithelial markers. Vimentin, N-Cadherin, E-Cadherin and fibronectin were measured with and without DUSP6 over-expression, and in response to several stimuli such as chemotherapy treatment. In particular, the high levels of vimentin were blunted at increasing doses of cisplatin in condition of DUSP6 over-expression while N-Cadherin contextually increased. Finally, DUSP6 per se increased invasion capacity of GBM. Overall, our data unveil the DUSP6 involvement in invasive mesenchymal-like properties in GBM.

Naringenin Sensitizes Resistant C6 Glioma Cells with a Repressive Impact on the Migrating Ability

Background:

Glioma, the most common form of a malignant brain tumour is characterised by a poor prognosis, which is attributable to its resistance against current therapeutic approaches. Temozolomide (TMZ), a DNA alkylating agent, is the first-line drug for glioma treatment. Long-term treatment using TMZ was reported to culminate in the development of resistance with overexpression of multidrug resistance 1 gene coded protein P-glycoprotein, which in turn releases the drugs from the tumour cells.

Purpose:

Thus, to circumvent such resistance issues, the current study attempted to explore the effect of naringenin (a flavanone) with proven antiglial tumour potential, in mitigating the features of TMZ resistance.

Methods:

Colony-forming assay, invasion assay and scratch wound assay were performed among the groups, namely tumour control (C6), vehicle control (V), naringenin (NGEN)-treated, drug-resistant tumour cells (C6R), and drug resistance cells added with NGEN (C6R+NGEN), to examine the impact of NGEN on migration and invasion. The effect of NGEN on filopodia length and density during cell migration was also studied in addition to the matrix metalloproteinases (MMP-2 and MMP-9) and p-ERK levels.

Results and Conclusion:

NGEN and C6R+NGEN groups had shown significant reduction (P < .01) in length and density of filopodia, colony formation, invasion and wound healing. Further, NGEN could also modify the assessed protein levels (P < .001), which were involved in migration and invasion in sensitive and resistant cells. Our study had provided the first evidence on NGEN-induced enhanced sensitivity against TMZ resistance with profound influence as an antimigratory and anti-invasive agent.

Research and Publication Ethics in Journal of Functional Morphology and Kinesiology

Research is required to minimize uncertainty and to be reproducible, that is, the design, implementation, evaluation, interpretation, and reporting of the presented data, must follow a good practice. An appropriate experimental design, an accurate execution of the study, a strict criticism of the obtained data while avoiding overestimation, as well as a suitable interpretation of main outcomes, represent key aspects in reporting and disseminating research to the scientific community. Furthermore, author contribution, responsibility, funding, acknowledgement, and adequately declaring any conflict of interest play important roles in science. The Journal of Functional Morphology and Kinesiology (JFMK), a member of the Committee on Publication Ethics (COPE), is committed to the highest scientific and ethical standards and encourages all authors to take into account and to comply, as much as possible, with the contents and issues reported in this technical note. This could be useful to improve the quality of the manuscripts and avoid misconduct, as well as to stimulate interest and debate, reflecting upon uses and misuses within our disciplines belonging to the medicine area (sports medicine and movement sciences) categories: anatomy, histology, orthopedics and sports medicine, rheumatology, sports sciences, physical therapy, sports therapy, and rehabilitation.

Craniomandibular Disorders in Pregnant Women: An Epidemiological Survey

Temporomandibular joint (TMJ) disorder has been reported to be 1.5 to two times more common in women than men. Such a gender-based difference could be attributed to behavioral, hormonal, anatomical, and psychological characteristics. Physiological hormonal differences between genders could be one of the possible explanations for the higher incidence of temporomandibular disorder (TMD) in women. As the plasma level of certain female hormones increases during gestation, it could be assumed that there is a higher prevalence of dysfunctional signs and symptoms in pregnant women. We performed an epidemiological survey based on screening for TMD in a group of 108 pregnant women and found that 72% of young women reported significant signs of TMJ disorders, 9% of the young women reported mild signs of TMJ disorders, and 19% of the included subjects reported no signs or symptoms of TMD. The presence of estrogen receptors in the temporomandibular joint of female baboons could be the basis of an explanation for the increased prevalence of dysfunction in young women reported in the literature and the high feedback we have seen of joint noises in pregnant women. On the basis of the present findings, it could be assumed that gestation period could represent a risk factor for craniomandibular dysfunctions.

4-Methylumbelliferone as a potent and selective antitumor drug on a glioblastoma model

Glioblastoma (GBM), the most frequent primary tumor of the central nervous system, has a median survival of 14.6 months. 4-Methylumbelliferone (4MU) is a coumarin derivative widely used as a hyaluronan synthesis inhibitor with proven antitumor activity and without toxic effects reported. We aim to evaluate the antitumor effect of 4MU alone or combined with temozolomide (TMZ) on a GBM cell line, its absence of toxicity on brain cells and its selectivity for tumor cells. The antitumor effect of 4MU alone or combined with TMZ was evaluated on GL26 cells by assessing the metabolic activity through the XTT assay, cell proliferation by BrdU incorporation assay, migration by the wound healing assay, cell death by fluorescein diacetate/propidium iodide (FDA/PI) staining, apoptosis by membrane asymmetry and DNA fragmentation and metalloproteinase activity by zymography. The levels of hyaluronan and its capacity to counteract the effects of 4MU and the expression of RHAMM and CD44 were also determined. The toxicity and selectivity of 4MU were determined by XTT assay and PI staining on normal brain primary cell culture (NBPC-GFP) and GL26/NBPC-GFP cocultures. The GL26 cells expressed RHAMM but not CD44 while synthetized hyaluronan. 4MU decreased hyaluronan synthesis, diminished proliferation and induced apoptosis while reducing cell migration and the activity of metalloproteinases, which was restored by addition of hyaluronic acid. Furthermore, 4MU sensitized GL26 cells to the TMZ effect and showed selective toxicity on tumor cells without exhibiting neurotoxic effects. We demonstrated for the first time the cytotoxic effect of 4MU on GBM cells, highlighting its potential usefulness to improve GBM treatment.

Targeting ADAM10 in Cancer and Autoimmunity

Generating inhibitors for A Disintegrin And Metalloproteinase 10 (ADAM10), a zinc-dependent protease, was heavily invested in by the pharmaceutical industry starting over 20 years ago. There has been much enthusiasm in basic research for these inhibitors, with a multitude of studies generating significant data, yet the clinical trials have not replicated the same results. ADAM10 is ubiquitously expressed and cleaves many important substrates such as Notch, PD-L1, EGFR/HER ligands, ICOS-L, TACI, and the "stress related molecules" MIC-A, MIC-B and ULBPs. This review goes through the most recent pre-clinical data with inhibitors as well as clinical data supporting the use of ADAM10 inhibitor use in cancer and autoimmunity. It additionally addresses how ADAM10 inhibitor therapy can be improved and if inhibitor therapy can be paired with other drug treatments to maximize effectiveness in various disease states. Finally, it examines the ADAM10 substrates that are important to each disease state and if any of these substrates or ADAM10 itself is a potential biomarker for disease.

Cycloastragenol as an Exogenous Enhancer of Chondrogenic Differentiation of Human Adipose-Derived Mesenchymal Stem Cells. A Morphological Study

Stem cell therapy and tissue engineering represent a promising approach for cartilage regeneration. However, they present limits in terms of mechanical properties and premature de-differentiation of engineered cartilage. Cycloastragenol (CAG), a triterpenoid saponin compound and a hydrolysis product of the main ingredient in Astragalus membranaceous, has been explored for cartilage regeneration. The aim of this study was to investigate CAG’s ability to promote cell proliferation, maintain cells in their stable active phenotype, and support the production of cartilaginous extracellular matrix (ECM) in human adipose-derived mesenchymal stem cells (hAMSCs) in up to 28 days of three-dimensional (3D) chondrogenic culture. The hAMSC pellets were cultured in chondrogenic medium (CM) and in CM supplemented with CAG (CAG–CM) for 7, 14, 21, and 28 days. At each time-point, the pellets were harvested for histological (hematoxylin and eosin (H&E)), histochemical (Alcian-Blue) and immunohistochemical analysis (Type I, II, and X collagen, aggrecan, SOX9, lubricin). After excluding CAG’s cytotoxicity (MTT Assay), improved cell condensation, higher glycosaminoglycans (sGAG) content, and increased cell proliferation have been detected in CAG–CM pellets until 28 days of culture. Overall, CAG improved the chondrogenic differentiation of hAMSCs, maintaining stable the active chondrocyte phenotype in up to 28 days of 3D in vitro chondrogenic culture. It is proposed that CAG might have a beneficial impact on cartilage regeneration approaches.

The Role of BEHAB/Brevican in the Tumor Microenvironment: Mediating Glioma Cell Invasion and Motility

Malignant gliomas are the most common tumors in the central nervous system (CNS) and, unfortunately, are also the most deadly. The lethal nature of malignant gliomas is due in large part to their unique and distinctive ability to invade the surrounding neural tissue. The invasive and dispersive nature of these tumors makes them particularly challenging to treat, and currently there are no effective therapies for malignant gliomas. The brain tumor microenvironment plays a particularly important role in mediating the invasiveness of gliomas, and, therefore, understanding its function is key to developing novel therapies to treat these deadly tumors. A defining aspect of the tumor microenvironment of gliomas is the unique composition of the extracellular matrix that enables tumors to overcome the typically inhibitory environment found in the CNS. One conspicuous component of the glioma tumor microenvironment is the neural-specific ECM molecule, brain-enriched hyaluronan binding (BEHAB)/brevican (B/b). B/b is highly overexpressed in gliomas, and its expression in these tumors contributes importantly to the tumor invasiveness and aggressiveness. However, B/b is a complicated protein with multiple splice variants, cleavage products, and glycoforms that contribute to its complex functions in these tumors and provide unique targets for tumor therapy. Here we review the role of B/b in glioma tumor microenvironment and explore targeting of this protein for glioma therapy.

Paeoniflorin: a monoterpene glycoside from plants of Paeoniaceae family with diverse anticancer activities

OBJECTIVES

Paeoniflorin, a representative pinane monoterpene glycoside in plants of Paeoniaceae family, possesses promising anticancer activities on diverse tumours. This paper summarized the advance of Paeoniflorin on cancers in vivo and in vitro, discussed the related molecular mechanisms, as well as suggested some perspectives of the future investigations.

KEY FINDINGS

Anticancer activities of paeoniflorin have been comprehensively investigated, including liver cancer, gastric cancer, breast cancer, lung cancer, pancreatic cancer, colorectal cancer, glioma, bladder cancer and leukaemia. Furthermore, the potential molecular mechanisms corresponding to the antitumour effects of Paeoniflorin might be related to the following aspects: inhibition of tumour cell proliferation and neovascularization, induction apoptosis, and inhibition of tumour invasion and metastasis.

SUMMARY

Paeoniflorin has wide spectrum antitumour activities; however, in vivo and clinical investigations on antitumour effect of Paeoniflorin are lacking which should be focused on further studies. Our present review on antitumour effects of Paeoniflorin would be beneficial for the further molecular mechanisms study, candidate antitumour drug development and clinical research of Paeoniflorin in the future.

Increased expression of MMP-2 and MMP-9 indicates poor prognosis in glioma recurrence

The main characteristic of glioma is recurrence, even after intensive multidisciplinary treatment. Studies show that enhanced invasive ability will increase the ability of tumor cells to escape from the primary tumor mass, which is a key factor contributing to tumor relapse and recurrence. In this study, we assessed the expression of MMP-2, MMP-9, two important matrix metallopeptidases that increase the invasive ability of glioma, and their suppressors, TIMP-1, TIMP-2 in glioma tissues from primary and recurrent glioma patients by immunohistochemistry. Glioma cells and nude mice were used for in vitro and in vivo studies. Results showed that the expression of MMP-2 and MMP-9 in recurrent gliomas were significantly higher than those in primary gliomas (P = 3.075 × 10^{-11, P = 1.510 × 10-5}, respectively). We also found that radiotherapy increased the expression of MMP-9, but had no effect on MMP-2 and TIMP-1/2. With glioma cell line U251, we found that irradiation increased the expression of MMP-9 in vitro. Tumor tissues from an orthotopic xenograft model showed that after irradiation treatment, the expression of MMP-9 increased significantly in vivo. We also found that knocking down MMP-9 decreased irradiation-induced invasion obviously. Above all, we concluded that higher expressions of MMP-2/-9 indicate poor prognosis in glioma recurrence. The increased expression of MMP-9 after radiotherapy suggests that MMP-9 might be an important target in the radiosensitization of glioma.

ADAMDEC1 Maintains a Growth Factor Signaling Loop in Cancer Stem Cells

Glioblastomas (GBM) are lethal brain tumors where poor outcome is attributed to cellular heterogeneity, therapeutic resistance, and a highly infiltrative nature. These characteristics are preferentially linked to GBM cancer stem cells (GSC), but how GSCs maintain their stemness is incompletely understood and the subject of intense investigation. Here, we identify a novel signaling loop that induces and maintains GSCs consisting of an atypical metalloproteinase, ADAMDEC1, secreted by GSCs. ADAMDEC1 rapidly solubilizes FGF2 to stimulate FGFR1 expressed on GSCs. FGFR1 signaling induces upregulation of ZEB1 via ERK1/2 that regulates ADAMDEC1 expression through miR-203, creating a positive feedback loop. Genetic or pharmacologic targeting of components of this axis attenuates self-renewal and tumor growth. These findings reveal a new signaling axis for GSC maintenance and highlight ADAMDEC1 and FGFR1 as potential therapeutic targets in GBM. SIGNIFICANCE: Cancer stem cells (CSC) drive tumor growth in many cancers including GBM. We identified a novel sheddase, ADAMDEC1, which initiates an FGF autocrine loop to promote stemness in CSCs. This loop can be targeted to reduce GBM growth.This article is highlighted in the In This Issue feature, p. 1469.

Cdh4 Down-Regulation Impairs in Vivo Infiltration and Malignancy in Patients Derived Glioblastoma Cells

The high invasive phenotype of glioblastoma is one of the main causes of therapy inefficacy and tumor relapse. Cell adhesion molecules of the cadherin family are involved in cell migration and are known as master regulators of epithelial tumor invasiveness, but their role in glioblastoma is less understood. In particular, we recently demonstrated, in the syngeneic murine model, the occurrence of a previously undescribed cadherin switch between Cdh2 and Cdh4 during gliomagenesis, which is necessary for the acquisition of the highly infiltrative and tumorigenic phenotype of these cells. In the present study, we tested the role of Cdh4 in human gliomas. Our results on patient-derived glioma cells demonstrate a positive correlation between Cdh4 expression levels and the loss of cell-cell contact inhibition of proliferation controls that allows cells to proliferate over confluence. Moreover, the silencing of Cdh4 by artificial microRNAs induced a decrease in the infiltrative ability of human glioma cells both in vitro and in vivo. More strikingly, Cdh4 silencing induced an impairment of the tumorigenic potential of these cells after orthotopic transplantation in immunodeficient mice. Overall, we conclude that in human glioblastoma, Cdh4 can also actively contribute in regulating cell invasiveness and malignancy.

Involvement of A3 Adenosine Receptor in Neuroblastoma Progression via Modulation of the Hypoxic/Angiogenic Pathway

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. The clinical course may range from spontaneous regression towards ganglioneuroblastoma/ganglioneuroma or maturation to a very aggressive form characterized by an extensive hypoxic area. In solid tumors, extracellular microenvironment hypoxia induces the transcription of hypoxia-inducible factors (HIFs) leading to synthesis of pro-angiogenic factor, VEGF; also, it increases extracellular adenosine production from ATP breakdown. To date, the role of this nucleoside in the hypoxic/angiogenic pathway characterizing the core of cancer mass has not been investigated yet. Therefore, the aim of the present study was to analyze the adenosine effect on modulation of the HIF-1α/2α/VEGF pathway mediated through A₃ AR binding. To this end, we have used a selective A₃ AR agonist IB-MECA or antagonist VUF 5574 in an in vitro model of malignant undifferentiated and all-trans retinoic acid (RA)-differentiated SH-SY5Y cells, representing the benign form of NB. Our results have shown that specific A₃ AR stimulation induces HIF and VEGF expression through the activation of mitogen-activated protein kinase/Erk kinase signaling cascade. In conclusion, the data suggest that A₃ AR may represent a marker of NB malignancy as well as a drug target for treatment of this solid tumor. Graphical Abstract.

The mechanical and pharmacological regulation of glioblastoma cell migration in 3D matrices

The invasion of glioblastoma is a complex process based on the interactions of tumor cells and the extracellular matrix. Tumors that are engineered using biomaterials are more physiologically relevant than a two-dimensional (2D) cell culture system. Matrix metalloproteinases and the plasminogen activator generated by tumor cells regulate a tumor's invasive behavior. In this study, microtumors were fabricated by encapsulating U87 glioma cells in Type I collagen and then glioma cell migration in the collagen hydrogels was investigated. Crosslinking of collagen with 8S-StarPEG increased the hydrogel viscosity and reduced the tumor cell migration speed in the hydrogels. The higher migration speed corresponded to the increased gene expression of MMP-2, MMP-9, urokinase plasminogen activator (uPA), and tissue plasminogen activator (tPA) in glioma cells grown in non-crosslinked collagen hydrogels. Inhibitors of these molecules hindered U87 and A172 cell migration in collagen hydrogels. Aprotinin and tranexamic acid did not inhibit U87 and A172 migration on the culture dish. This study demonstrated the differential effect of pharmacologic molecules on tumor cell motility in either a 2D or three-dimensional culture environment.

Tetrandrine inhibits human brain glioblastoma multiforme GBM 8401 cancer cell migration and invasion in vitro

Tetrandrine (TET) has been reported to induce anti-cancer activity in many human cancer cells and also to inhibit cancer cell migration and invasion. However, there are no reports to show TET inhibits cell migration and invasion in human brain glioblastoma multiforme GBM 8401 cells. In this study, we investigated the anti-metastasis effects of TET on GBM 8401 cells in vitro. Under sub-lethal concentrations (from 1, 5 up to 10 μM), TET significantly inhibited cell mobility, migration and invasion of GBM 8401 cells that were assayed by wound healing and Transwell assays. Gelatin zymography assay showed that TET inhibited MMP-2 activity in GBM 8401 cells. Western blotting results indicated that TET inhibited several key metastasis-related proteins, such as p-EGFR_(Tyr1068) , SOS-1, GRB2, Ras, p-AKT_(Ser473) and p-AKT_(Thr308) , NF-κB-p65, Snail, E-cadherin, N-cadherin, NF-κB, MMP-2 and MMP-9 that were significant reduction at 24 and 48 hours treatment by TET. TET reduced MAPK signaling associated proteins such as p-JNK1/2 and p-c-Jun in GBM 8401 cells. The electrophoretic mobility shift (EMSA) assay was used to investigate NF-κB and DNA binding was reduced by TET in a dose-dependently. Based on these findings, we suggested that TET could be used in anti-metastasis of human brain glioblastoma multiforme GBM 8401 cells in the future.

Adapted Moderate Training Exercise Decreases the Expression of Ngal in the Rat Kidney: An Immunohistochemical Study

Neutrophil gelatinase-associated lipocalin (NGAL) is a biomarker of several injuries and is upregulated in inflammatory conditions. Vitamin D was shown to have anti-inflammatory effects and to increase after physical activity. This work aimed to assess, through immunohistochemistry, the effects of an adapted moderate training exercise (AMTE) on the expression of NGAL and vitamin D receptor (VDR) in the kidney and heart of rats. Sixteen rats were distributed into two groups: the sedentary control group and the experimental group, subjected to AMTE on the treadmill for 12 weeks. The results showed the basal expression of NGAL and VDR in both the heart and the kidney in sedentary rats; no differences in the expression of both NGAL and VDR in the heart; and a decreased NGAL and an increased VDR expression in the kidney of rats subjected to AMTE. These results suggest a possible protective role of AMTE on NGAL-associated injuries in the kidney, probably through the vitamin D signaling pathway. Our results represent an interesting preliminary data that may open new horizons in the management of NGAL-associated kidney injuries. However, further studies are needed to confirm these results and to comprehend the specific interaction between NGAL and VDR pathways in the kidney.

Naringenin inhibited migration and invasion of glioblastoma cells through multiple mechanisms

Glioblastoma (GBM) is the most mortality brain cancer in the world. Due to high invasion and drug resistance cause the poor prognosis of GBM. Naringenin, an ingredient of citrus, exhibits many cellular functions such as antioxidant, anti-inflammation, and anticancer. Naringenin inhibits the migration of bladder and lung cancer via modulation of MMP-2 and/or MMP-9 activities, Naringenin inhibits migration and trigger apoptosis in gastric cancer cells through downregulation of AKT pathway. However, the effects of naringenin in GBM still remain to be elucidated. In this study, we reveal the molecular mechanisms of naringenin in the inhibition of migration and invasion in GBM. No overt alternation of cell proliferation was found in of GBM 8901 cells treated with different concentration of naringenin. Slight decreased cell viability was found in GBM 8401 cell treated with 200 and 300 μM naringenin. Significant reduction of migration and invasion as assayed by Boyden chamber analysis was found in of GBM cells treated with 100, 200, and 300 μM naringenin. Zymography analysis also revealed that the activities of MMP-2 and MMP-9 of GBM cells were significantly inhibited in response to 100, 200, or 300 μM naringenin treatment. Proteins of MMP-2 and MMP-9 were downregulated in naringenin treated GBM cells. In addition, naringenin also attenuated the activities of ERK and p38. Naringenin decreased mesenchymal markers (snail and slug) expression as revealed by Western blot analysis. Taken together, our findings indicated that naringenin eliminated the migration and invasion of GBM cells through multiple mechanisms including inhibition of MMPs, ERK, and p38 activities and modulation of EMT markers. Our results also suggested that naringenin may be a potential agent to prevent metastasis of GBM.

Current natural therapies in the treatment against glioblastoma

Glioblastoma (GBM) is the most common and aggressive brain tumor, which causes the highest number of deaths worldwide. It is a highly vascularized tumor, infiltrative, and its tumorigenic capacity is exacerbated. All these hallmarks are therapeutic targets in GBM treatment, including surgical removal followed by radiotherapy and chemotherapy. Current therapies have not been sufficient for the effective patient's management, so the classic therapies have had to expand and incorporate new alternative treatments, including natural compounds. This review summarizes natural products and their physiological effects in in vitro and in vivo models of GBM, specifically by modulating signaling pathways involved in angiogenesis, cell migration/invasion, cell viability, apoptosis, and chemoresistance. The most important aspects of natural products and their derivatives were described in relation to its antitumoral effects. As a final result, it can be obtained that within the compounds with more evidence that supports or suggests its clinical use are the cannabinoids, terpenes, and curcumin, because many have been shown to have a significant effect in decreasing the progress of GBM through known mechanisms, such as chemo-sensitization or decrease migration and cell invasion. Natural compounds emerge as promising therapies to attack the progress of GBM.

Paeoniflorin Inhibits Migration and Invasion of Human Glioblastoma Cells via Suppression Transforming Growth Factor β-Induced Epithelial-Mesenchymal Transition

Paeoniflorin (PF) is a polyphenolic compound derived from Radix Paeoniae Alba thathas anti-cancer activities in a variety of human malignancies including glioblastoma. However, the underlying mechanisms have not been fully elucidated. Epithelial to mesenchymal transition (EMT), characterized as losing cell polarity, plays an essential role in tumor invasion and metastasis. TGFβ, a key member of transforming growth factors, has been demonstrated to contribute to glioblastoma aggressiveness through inducing EMT. Therefore, the present studies aim to investigate whether PF suppresses the expression of TGFβ and inhibits EMT that plays an important role in anti-glioblastoma. We found that PF dose-dependently downregulates the expression of TGFβ, enhances apoptosis, reduces cell proliferation, migration and invasion in three human glioblastoma cell lines (U87, U251, T98G). These effects are enhanced in TGFβ siRNA treated cells and abolished in cells transfected with TGFβ lentiviruses. In addition, other EMT markers such as snail, vimentin and N-cadherin were suppressed by PF in these cell lines and in BALB/c nude mice injected with U87 cells. The expression of MMP2/9, EMT markers, are also dose-dependently reduced in PF treated cells and in U87 xenograft mouse model. Moreover, the tumor sizes are reduced by PF treatment while there is no change in body weight. These results indicate that PF is a potential novel drug target for the treatment of glioblastoma by suppression of TGFβ signaling pathway and inhibition of EMT.

Tea polyphenols ameliorates neural redox imbalance and mitochondrial dysfunction via mechanisms linking the key circadian regular Bmal1

Circadian rhythms are autonomous anticipatory oscillators that control a large array of physiological and metabolic processes. Compelling evidence points toward an interplay between circadian rhythms and cellular redox metabolism. Dysregulation of circadian rhythms is associated with neurodegenerative diseases and accelerated aging. Tea polyphenols (TP) is one of the most used antioxidants and exerts beneficial effect on neurodegenerative diseases. The aim of this study is to investigate whether circadian clock mechanisms are involved in the protection effect of TP against neural redox imbalance and mitochondrial dysfunction in SH-SY5Y cells. In the current study, our results revealed that TP, as a Bmal1-enhancing natural compound, can reverse the relatively shallow daily oscillations of circadian clock genes transcription and protein expression in SH-SY5Y neuronal cells under oxidative stress conditions. Furthermore, TP pretreatment significantly ameliorated H2O2-elicited mitochondria impairment via manipulating mitochondrial dynamics and mitochondrial membrane potential, which is consistent with the recovery in expression of mitochondrial respiration complex I-IV in Bmal1-dependent efficiency. Furthermore, Bmal1 is involved in TP-stimulated Nrf2/ARE/HO-1 and AKT/CREB/BDNF signaling pathway. Hence, TP may serve as a nutritional preventive strategy in the recovery of oxidative stress-related neurodegenerative disease via modulating circadian clock.

Andrographolide suppresses the migratory ability of human glioblastoma multiforme cells by targeting ERK1/2-mediated matrix metalloproteinase-2 expression

Glioblastoma multiforme (GBM) can be a fatal tumor because of difficulties in treating the related metastasis. Andrographolide is the bioactive component of the Andrographis paniculata. Andrographolide possesses the anti-inflammatory activity and inhibits the growth of various cancers; however, its effect on GBM cancer motility remains largely unknown. In this study, we examined the antimetastatic properties of andrographolide in human GBM cells. Our results revealed that andrographolide inhibited the invasion and migration abilities of GBM8401 and U251 cells. Furthermore, andrographolide inhibited matrix metalloproteinase (MMP)-2 activity and expression. Real-time PCR and promoter activity assays indicated that andrographolide inhibited MMP-2 expression at the transcriptional level. Such inhibitory effects were associated with the suppression of CREB DNA-binding activity and CREB expression. Mechanistically, andrographolide inhibited the cell motility of GBM8401 cells through the extracellular-regulated kinase (ERK) 1/2 pathway, and the blocking of the ERK 1/2 pathway could reverse MMP-2-mediated cell motility. In conclusion, CREB is a crucial target of andrographolide for suppressing MMP-2-mediated cell motility in GBM cells. Therefore, a combination of andrographolide and an ERK inhibitor might be a good strategy for preventing GBM metastasis.

EGF stimulates glioblastoma metastasis by induction of matrix metalloproteinase-9 in an EGFR-dependent mechanism

Epidermal growth factor (EGF) and EGF receptor (EGFR) play prominent roles in the metastasis of glioblastoma (GBM). However, the molecular mechanisms for the function of EGF and EGFR in GBM metastasis have not been elucidated. Herein, we demonstrate that coactivation of EGF and EGFR drives tumor metastasis in a matrix metalloproteinase-9 (MMP-9)-dependent manner. Expression levels of EGF, EGFR, and MMP-9 were substantially upregulated in the GBM and edema zones of patients, compared with those of paired unaffected participants. Secretion of EGF and MMP-9 was reduced in the cerebrospinal fluid (CSF) after removing GBM for 2 weeks by operation. To the mechanism, MMP-9 was upregulated by activating EGF and EGFR via PI3K/AKT- and ERK1/2-dependent pathways. Moreover, signal transducer and activator of transcription (STAT) 3 and STAT5 mediated the activation of NF-κB by PI3K/AKT and ERK1/2 pathways. This resulted in transactivation of MMP-9 in GBM. Finally, MMP-9 induction facilitated abnormal proliferation, migration, and invasion of cells, which contributed to GBM metastasis.

Effect of Necrosis on the miRNA-mRNA Regulatory Network in CRT-MG Human Astroglioma Cells

Purpose

Glioblastoma multiforme (GBM) is the most common adult primary intracranial tumor. The remarkable features of GBM include central necrosis. MicroRNAs (miRNAs) have been considered as diagnostic/prognostic biomarkers for many cancers, including glioblastoma. However, the effect of necrosis on the miRNA expression profile and predicted miRNA-mRNA regulatory information remain unclear. The purpose of this study is to examine the effect of necrotic cells on the modulation of miRNA and mRNA expression profiles and miRNA-mRNA network in CRT-MG cells.

Materials and Methods

We used human astroglioma cells, CRT-MG, treated with necrotic CRT-MG cells to examine the effect of necrosis on the modulation of miRNA and mRNA by next-generation sequencing. For preparation of necrotic cells, CRT-MGcellswere frozen and thawed through cycle of liquid nitrogen–water bath. The putative miRNA-mRNA regulatory relationshipwas inferred through target information, using miRDB.

Results

The necrotic cells induced dysregulation of 106 miRNAs and 887 mRNAs. Among them, 11 miRNAs that had a negative correlation value of p < 0.05 by the hypergeometric test were screened, and their target mRNAs were analyzed by Gene Ontology enrichment analysis. Using the Kyoto Encyclopedia of Genes and Genomes database, we also found several necrotic cell treatment-activated pathways that were modulated by relevant gene targets of differentially expressed miRNAs.

Conclusion

Our result demonstrated that dysregulation of miRNA and mRNA expression profiles occurs when GBM cells are exposed to necrotic cells, suggesting that several miRNAs may have the potential to be used as biomarkers for predicting GBM progression and pathogenesis.

Integrating the glioblastoma microenvironment into engineered experimental models

Glioblastoma (GBM) is the most lethal cancer originating in the brain. Its high mortality rate has been attributed to therapeutic resistance and rapid, diffuse invasion - both of which are strongly influenced by the unique microenvironment. Thus, there is a need to develop new models that mimic individual microenvironmental features and are able to provide clinically relevant data. Current understanding of the effects of the microenvironment on GBM progression, established experimental models of GBM and recent developments using bioengineered microenvironments as ex vivo experimental platforms that mimic the biochemical and physical properties of GBM tumors are discussed.

Overexpression of N-cadherin and β-catenin correlates with poor prognosis in patients with nasopharyngeal carcinoma

An increasing amount of evidence demonstrates that epithelial-mesenchymal transition (EMT) is important in tumor invasion and metastases. The cell-cell adhesion molecule N-cadherin and the Wnt/β-catenin cascade protein β-catenin are two biomarkers of EMT. The present study aimed to measure the expression levels of N-cadherin and β-catenin in samples from patients with nasopharyngeal carcinoma (NPC) and evaluate their prognostic significance. N-cadherin and β-catenin mRNA was evaluated using reverse transcription-quantitative polymerase chain reaction in 26 NPC tissue samples and 8 nasopharyngeal epithelium samples. Protein expression of N-cadherin and β-catenin was also detected using immunohistochemistry in 128 archival NPC paraffin-embedded specimens. Finally, associations between clinical pathological parameters and prognostic values in NPC were evaluated. The results demonstrated that both the mRNA and protein levels of N-cadherin and β-catenin were significantly increased in NPC tissues compared with the controls. Enhanced expression of N-cadherin and β-catenin protein was strongly correlated with the status of lymph node metastasis and clinical stages in patients with NPC. Notably, high expression of N-cadherin and β-catenin proteins was significantly correlated with lower overall survival (OS) rate in patients with NPC. Finally, multivariate analysis demonstrated that expression of N-cadherin protein and clinical stages were independent prognostic factors for patients with NPC. Therefore, the present study demonstrated that N-cadherin and β-catenin expression may be used as potential prognostic biomarkers for patients with NPC.

Zinc and zinc-containing biomolecules in childhood brain tumors

Zinc ions are essential cofactors of a wide range of enzymes, transcription factors, and other regulatory proteins. Moreover, zinc is also involved in cellular signaling and enzymes inhibition. Zinc dysregulation, deficiency, over-supply, and imbalance in zinc ion transporters regulation are connected with various diseases including cancer. A zinc ion pool is maintained by two types of proteins: (i) zinc-binding proteins, which act as a buffer and intracellular donors of zinc and (ii) zinc transporters responsible for zinc fluxes into/from cells and organelles. The decreased serum zinc ion levels have been identified in patients suffering from various cancer diseases, including head and neck tumors and breast, prostate, liver, and lung cancer. On the contrary, increased zinc ion levels have been found in breast cancer and other malignant tissues. Zinc metalloproteomes of a majority of tumors including brain ones are still not yet fully understood. Current knowledge show that zinc ion levels and detection of certain zinc-containing proteins may be utilized for diagnostic and prognostic purposes. In addition, these proteins can also be promising therapeutic targets. The aim of the present work is an overview of the importance of zinc ions, zinc transporters, and zinc-containing proteins in brain tumors, which are, after leukemia, the second most common type of childhood cancer and the second leading cause of death in children after accidents.

Metalloproteinases ADAM10 and ADAM17 Mediate Migration and Differentiation in Glioblastoma Sphere-Forming Cells

Glioblastoma is the most common form of primary malignant brain tumour. These tumours are highly proliferative and infiltrative resulting in a median patient survival of only 14 months from diagnosis. The current treatment regimens are ineffective against the small population of cancer stem cells residing in the tumourigenic niche; however, a new therapeutic approach could involve the removal of these cells from the microenvironment that maintains the cancer stem cell phenotype. We have isolated multipotent sphere-forming cells from human high grade glioma (glioma sphere-forming cells (GSCs)) to investigate the adhesive and migratory properties of these cells in vitro. We have focused on the role of two closely related metalloproteinases ADAM10 and ADAM17 due to their high expression in glioblastoma and GSCs and their ability to activate cytokines and growth factors. Here, we report that ADAM10 and ADAM17 inhibition selectively increases GSC, but not neural stem cell, migration and that the migrated GSCs exhibit a differentiated phenotype. We also observed a correlation between nestin, a stem/progenitor marker, and fibronectin, an extracellular matrix protein, expression in high grade glioma tissues. GSCs adherence on fibronectin is mediated by α5β1 integrin, where fibronectin further promotes GSC migration and is an effective candidate for in vivo cancer stem cell migration out of the tumourigenic niche. Our results suggest that therapies against ADAM10 and ADAM17 may promote cancer stem cell migration away from the tumourigenic niche resulting in a differentiated phenotype that is more susceptible to treatment.

PDIA6 regulation of ADAM17 shedding activity and EGFR-mediated migration and invasion of glioblastoma cells

OBJECTIVE

In patients with glioblastoma, local invasion of tumor cells causes recurrence and shortens survival. The goal of this study was to determine whether protein disulfide isomerase (PDI) A6 regulates migration and invasion of glioblastoma cells and the associated factors.

METHODS

U87MG cells were treated with either PDIA6 or ADAM17 small interfering RNA (siRNA) fragments or with both types of siRNA fragments, and expression was confirmed by reverse transcription–polymerase chain reaction and Western blot. Migration and invasion were assessed using a wound-healing assay, a Matrigel assay, and an organotypic culture system. After the U87MG cells were treated with siRNAs and epidermal growth factor receptor (EGFR) inhibitors, the expression of matrix metalloproteinase–2 (MMP-2), membrane Type 1-matrix metalloproteinase (MT1-MMP), integrin, phosphorylated focal adhesion kinase (pFAK), and phosphorylated EGFR (pEGFR) was detected by Western blotting and zymography.

RESULTS

U87MG cell migration and invasion increased significantly after inhibition of PDIA6. The MMP-2 activation ratio and ADAM17 activity (as a sheddase of the proligand) increased, and expression of pEGFR, pFAK, integrin α5β3, and MT1-MMP was induced, compared with control levels. Furthermore, heparin-binding epidermal growth factor (EGFR signaling ligand) was highly expressed in PDIA6-knockdown cells. After siPDIA6-transfected U87MG cells were treated with EGFR signaling inhibitors, expression of pFAK, MMP-2, and MT1-MMP decreased and invasion decreased significantly. Simultaneous double-knockdown of PDIA6 and ADAM17 reduced pEGFR and pFAK expression, compared with control levels.

CONCLUSIONS

The authors propose that inhibiting PDIA6 could transduce EGFR signaling by activating and inducing ADAM17 during migration and invasion of U87MG glioblastoma cells. The results of this study suggest that PDIA6 is an important component of EGFR-mediated migration and invasion of U87MG cells. This is the first report of the effects of PDIA6 on migration and invasion in glioblastoma.