Aurora A plays a dual role in migration and survival of human glioblastoma cells according to the CXCL12 concentration

Nanotechnology for enhanced nose-to-brain drug delivery in treating neurological diseases

Despite the increasing global incidence of brain disorders, achieving sufficient delivery towards the central nervous system (CNS) remains a formidable challenge in terms of translating into improved clinical outcomes. The brain is highly safeguarded by physiological barriers, primarily the blood-brain barrier (BBB), which routinely excludes most therapeutics from entering the brain following systemic administration. Among various strategies investigated to circumvent this challenge, intranasal administration, a noninvasive method that bypasses the BBB to allow direct access of drugs to the CNS, has been showing promising results. Nanotechnology-based drug delivery systems, in particular, have demonstrated remarkable capacities in overcoming the challenges posed by nose-to-brain drug delivery and facilitating targeted drug accumulation within the brain while minimizing side effects of systemic distribution. This review comprehensively summarizes the barriers of nose-to-brain drug delivery, aiming to enhance our understanding of potential physiological obstacles and improve the efficacy of nasal delivery in future trials. We then highlight cutting-edge nanotechnology-based studies that enhance nose-to-brain drug delivery in three key aspects, demonstrating substantial potential for improved treatment of brain diseases. Furthermore, the attention towards clinical studies will ease the regulatory approval process for nasal administration of nanomedicines targeting brain disease.

Development of an intraventricular adeno-associated virus-based labeling strategy for glioblastoma cells nested in the subventricular zone

Background

Glioblastoma (GBM) is a dreadful brain tumor, with a particular relationship to the adult subventricular zone (SVZ) that has been described as relevant to disease initiation, progression, and recurrence.

Methods

We propose a novel strategy for the detection and tracking of xenografted GBM cells that are located in the SVZ, based on an intracerebroventricular (icv) recombinant adeno-associated virus (AAV)-mediated color conversion method. We used different patient-derived GBM stem-like cells (GSCs), which we transduced first with a retroviral vector (LRLG) that included a lox-dsRed-STOP-lox cassette, upstream of the eGFP gene, then with rAAVs expressing the Cre-recombinase. Red and green fluorescence is analyzed in vitro and in vivo using flow cytometry and fluorescence microscopy.

Results

After comparing the efficiency of diverse rAAV serotypes, we confirmed that the in vitro transduction of GSC-LRLG with rAAV-Cre induced a switch from red to green fluorescence. In parallel, we verified that rAAV transduction was confined to the walls of the lateral ventricles. We, therefore, applied this conversion approach in 2 patient-derived orthotopic GSC xenograft models and showed that the icv injection of an rAAV-DJ-Cre after GSC-LRLG tumor implantation triggered the conversion of red GSCs to green, in the periventricular region. Green GSCs were also found at distant places, including the migratory tract and the tumor core.

Conclusions

This study not only sheds light on the putative outcome of SVZ-nested GBM cells but also shows that icv injection of rAAV vectors allows to transduce and potentially modulate gene expression in hard-to-reach GBM cells of the periventricular area.

Combined Aurora Kinase A and CHK1 Inhibition Enhances Radiosensitivity of Triple-Negative Breast Cancer Through Induction of Apoptosis and Mitotic Catastrophe Associated With Excessive DNA Damage

PURPOSE

There is an urgent need for biomarkers and new actionable targets to improve radiosensitivity of triple-negative breast cancer (TNBC) tumors. We characterized the radiosensitizing effects and underlying mechanisms of combined Aurora kinase A (AURKA) and CHK1 inhibition in TNBC.

METHODS AND MATERIALS

Different TNBC cell lines were treated with AURKA inhibitor (AURKAi, MLN8237) and CHK1 inhibitor (CHK1i, MK8776). Cell responses to irradiation (IR) were then evaluated. Cell apoptosis, DNA damage, cell cycle distribution, and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and Phosphoinositide 3-Kinase (PI3K) pathways were evaluated in vitro. Transcriptomic analysis was performed to facilitate the identification of potential biomarkers. Xenograft and immunohistochemistry were carried out to investigate the radiosensitizing effects of dual inhibition in vivo. Finally, the prognostic effect of CHEK1/AURKA in TNBC samples in the The Cancer Genome Atlas (TCGA) database and our center were analyzed.

RESULTS

AURKAi (MLN8237) induced overexpression of phospho-CHK1 in TNBC cells. The addition of MK8776 (CHK1i) to MLN8237 greatly reduced cell viability and increased radiosensitivity compared with either the control or MLN8237 alone in vitro. Mechanistically, dual inhibition resulted in inducing excessive DNA damage by prompting G2/M transition to cells with defective spindles, leading to mitotic catastrophe and induction of apoptosis after IR. We also observed that dual inhibition suppressed the phosphorylation of ERK, while activation of ERK with its agonist or overexpression of active ERK1/2 allele could attenuate the apoptosis induced by dual inhibition with IR. Additionally, dual inhibition of AURKA and CHK1 synergistically enhanced radiosensitivity in MDA-MB-231 xenografts. Moreover, we detected that both CHEK1 and AURKA were overexpressed in patients with TNBC and negatively correlated with patient survival.

CONCLUSIONS

Our findings suggested that AURKAi in combination with CHK1i enhanced TNBC radiosensitivity in preclinical models, potentially providing a novel strategy of precision treatment for patients with TNBC.

Increase in serum vimentin levels in patients with glioma and its correlation with prognosis of patients with glioblastoma

Early diagnosis of glioma is of great value to improve prognosis. We focused on serum vimentin levels as a useful biomarker for preoperative diagnosis. The aim of this study was to determine whether serum vimentin levels in patients with glioma are significantly higher than those of healthy adult volunteer and whether the serum vimentin level is associated with overall survival (OS) in patients with glioblastoma (GBM). This study included 52 consecutive patients with newly diagnosed glioma and a control group of 13 healthy adult volunteers. We measured serum vimentin levels in blood samples obtained from patients with glioma preoperatively and a control group. Furthermore, we investigated the correlation between serum vimentin levels and OS in patients with GBM. The serum vimentin levels of patients with glioma were significantly higher than those of the control group. The serum vimentin level of 2.9 ng/ml was the optimal value for differentiating patients with glioma from the control group with a sensitivity of 92.3% and specificity of 88.5%. The serum vimentin levels correlated significantly with immunoreactivity for survivin. In 27 patients with GBM, serum vimentin levels (cutoff value, median value 53.3 ng/ml) correlated with OS in univariate and multivariate analyses. Our study revealed that serum vimentin levels of patients with glioma are significantly higher than those of the control group. Therefore, we believe that serum vimentin level might be a useful and practical biomarker for preoperative diagnosis of glioma. Furthermore, high serum vimentin levels correlated significantly with shorter OS in patients with GBM.

Intranasal Pathway for Nanoparticles to Enter the Central Nervous System

Intranasal administration was previously proposed for delivering drugs for central nervous system (CNS) diseases. However, the delivery and elimination pathways, which are very imperative to know for exploring the therapeutic applications of any given CNS drugs, remain far from clear. Because lipophilicity has a high priority in the design of CNS drugs, the as-prepared CNS drugs tend to form aggregates. Therefore, a PEGylated Fe₃O₄ nanoparticle labeled with a fluorescent dye was prepared as a model drug and studied to elucidate the delivery pathways of intranasally administered nanodrugs. Through magnetic resonance imaging, the distribution of the nanoparticles was investigated in vivo. Through ex vivo fluorescence imaging and microscopy studies, more precise distribution of the nanoparticles across the entire brain was disclosed. Moreover, the elimination of the nanoparticles from cerebrospinal fluid was carefully studied. The temporal dose levels of intranasally delivered nanodrugs in different parts of the brain were also investigated.

Emerging roles of Aurora-A kinase in cancer therapy resistance

Aurora kinase A (Aurora-A), a serine/threonine kinase, plays a pivotal role in various cellular processes, including mitotic entry, centrosome maturation and spindle formation. Overexpression or gene-amplification/mutation of Aurora-A kinase occurs in different types of cancer, including lung cancer, colorectal cancer, and breast cancer. Alteration of Aurora-A impacts multiple cancer hallmarks, especially, immortalization, energy metabolism, immune escape and cell death resistance which are involved in cancer progression and resistance. This review highlights the most recent advances in the oncogenic roles and related multiple cancer hallmarks of Aurora-A kinase-driving cancer therapy resistance, including chemoresistance (taxanes, cisplatin, cyclophosphamide), targeted therapy resistance (osimertinib, imatinib, sorafenib, etc.), endocrine therapy resistance (tamoxifen, fulvestrant) and radioresistance. Specifically, the mechanisms of Aurora-A kinase promote acquired resistance through modulating DNA damage repair, feedback activation bypass pathways, resistance to apoptosis, necroptosis and autophagy, metastasis, and stemness. Noticeably, our review also summarizes the promising synthetic lethality strategy for Aurora-A inhibitors in RB1, ARID1A and MYC gene mutation tumors, and potential synergistic strategy for mTOR, PAK1, MDM2, MEK inhibitors or PD-L1 antibodies combined with targeting Aurora-A kinase. In addition, we discuss the design and development of the novel class of Aurora-A inhibitors in precision medicine for cancer treatment.

Nucleic acid drug vectors for diagnosis and treatment of brain diseases

Nucleic acid drugs have the advantages of rich target selection, simple in design, good and enduring effect. They have been demonstrated to have irreplaceable superiority in brain disease treatment, while vectors are a decisive factor in therapeutic efficacy. Strict physiological barriers, such as degradation and clearance in circulation, blood-brain barrier, cellular uptake, endosome/lysosome barriers, release, obstruct the delivery of nucleic acid drugs to the brain by the vectors. Nucleic acid drugs against a single target are inefficient in treating brain diseases of complex pathogenesis. Differences between individual patients lead to severe uncertainties in brain disease treatment with nucleic acid drugs. In this Review, we briefly summarize the classification of nucleic acid drugs. Next, we discuss physiological barriers during drug delivery and universal coping strategies and introduce the application methods of these universal strategies to nucleic acid drug vectors. Subsequently, we explore nucleic acid drug-based multidrug regimens for the combination treatment of brain diseases and the construction of the corresponding vectors. In the following, we address the feasibility of patient stratification and personalized therapy through diagnostic information from medical imaging and the manner of introducing contrast agents into vectors. Finally, we take a perspective on the future feasibility and remaining challenges of vector-based integrated diagnosis and gene therapy for brain diseases.

Identification of Ferroptosis-Related Genes in Laryngeal Carcinoma Using an Integrated Bioinformatics Approach

Amaç: Hücre içi demir birikimi ve lipid peroksidasyonu ile karakterize edilen ferroptoz, tümör baskılanmasında önemli rol oynayabilen yeni tanımlanmış bir hücre ölüm şeklidir. Larengeal skuamöz hücreli karsinom (LSHK) ve ferroptozis arasındaki ilişki hakkında yapılan çalışmalar sınırlıdır. Bu çalışmanın amacı, LSHK' nin tanı, tedavisinde ve ferroptozis ile ilgili belirteçleri in siliko yöntemleri kullanarak saptamaktır.Yöntem: Ferroptoz ile ilgili genler, FerrDb veri tabanından elde edildi. The Cancer Genome Atlas (TCGA) veri setlerinden LSHK hastalarının mRNA ekspresyon verileri ve ferroptoz ile ilgili bazı genleri taramak için kullanıldı. LSHK ile ilgili GSE143224 ve GSE84957 mikrodizi veri setleri GEO veri tabanından elde edilmiştir. Tüm veri setleri kullanılarak ferroptoz ve LSHK ile ilişkili genleri elde etmek için örtüşen veriler kullanılmıştır. LSHK grubu ve normal kontroller arasındaki diferansiyel olarak eksprese edilen genler (DEG'ler) ve ferroptoz ile ilgili DEG'ler, biyoinformatik yöntemler kullanılarak analiz edildi. Daha sonra STRING ve Cytoscape yazılımları kullanılarak Gene Ontology (GO), KEGG ve protein-protein etkileşimi (PPE) ağı analizleri gerçekleştirilmiştir.Bulgular: Ferroptoz ile ilgili 259 gen, FerrDb veri tabanından alındı ve ferroptoz DEG'lerini tanımlamak için bunları TCGA-HNSC (523 örnek), GSE143224 (25 örnek) ve GSE84957 (18 örnek) ile analizleri yapıldı. Analiz sonrasında 13 adet yukarı regüle edilmiş (NOX4, BID, ABCC1, TNFAIP3, PANX1, SLC1A4, SLC3A2, FTL, TFRC, AURKA, HSF1, PML, CA9; p<0.05) ve 3 adet aşağı regüle edilmiş gen (CHAC1, LPIN1, MUC1; p<0.05) saptanmıştır. GO, KEGG ve PPE analizleri ile elde edilen hücresel stres, inflamasyon, oksidatif stres ve karsinogenez süreçlerine benzer sonuçlar (p<0.05) ile bu genlerin LSHK' nin ilerlemesinde rol oynayabileceğini göstermektedir.Sonuç: Sonuç olarak, bu çalışmada LSHK'de ferroptoz ile yakından ilişkili olan ve LSHK hastalarını sağlıklı kontrollerden ayırt edebilen 16 potansiyel gen saptanmıştır. Çalışmamız, LSHK’nin moleküler mekanizmasını ve terapötik hedeflerini keşfetmek için daha geniş bir fikir sağlayabilir.

Comprehensive metabolomics study on the pathogenesis of anaplastic astrocytoma via UPLC-Q/TOF-MS

Anaplastic astrocytoma (AA) is a malignant carcinoma whose pathogenesis remains to be fully elucidated. System biology techniques have been widely used to clarify the mechanism of diseases from a systematic perspective. The present study aimed to explore the pathogenesis and novel potential biomarkers for the diagnosis of AA according to metabolic differences. Patients with AA (n = 12) and healthy controls (n = 15) were recruited. Serum was assayed with untargeted ultraperformance liquid chromatography-quadrupole/time-of-flight-mass spectrometry (UPLC-Q/TOF-MS) metabolomic techniques. The data were further evaluated using multivariate analysis and bioinformatic methods based on the KEGG database to determine the distinct metabolites and perturbed pathways. Principal component analysis and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) identified the significance of the distinct metabolic pattern between patients with AA and healthy controls (P < .001) in both ESI modes. Permutation testing confirmed the validity of the OPLS-DA model (permutation = 200, Q2 < 0.5). In total, 24 differentiated metabolites and 5 metabolic pathways, including sphingolipid, glycerophospholipid, caffeine, linoleic acid, and porphyrin metabolism, were identified based on the OPLS-DA model. 3-Methylxanthine, sphinganine, LysoPC(18:1), and lactosylceramide were recognized as potential biomarkers with excellent sensitivity and specificity (area under the curve > 98%). These findings indicate that the perturbed metabolic pattern related to immune regulation and cellular signal transduction is associated with the pathogenesis of AA. 3-Methylxanthine, sphinganine, LysoPC(18:1), and lactosylceramide could be used as biomarkers of AA in future clinical practice. This study provides a therapeutic basis for further studies on the mechanism and precise clinical diagnosis of AA.

The scaffold protein NEDD9 is necessary for leukemia-cell migration and disease progression in a mouse model of chronic lymphocytic leukemia

The scaffold protein NEDD9 is frequently upregulated and hyperphosphorylated in cancers, and is associated with poor clinical outcome. NEDD9 promotes B-cell adhesion, migration and chemotaxis, pivotal processes for malignant development. We show that global or B-cell-specific deletion of Nedd9 in chronic lymphocytic leukemia (CLL) mouse models delayed CLL development, markedly reduced disease burden and resulted in significant survival benefit. NEDD9 was required for efficient CLL cell homing, chemotaxis, migration and adhesion. In CLL patients, peripheral NEDD9 expression was associated with adhesion and migration signatures as well as leukocyte count. Additionally, CLL lymph nodes frequently expressed high NEDD9 levels, with a subset of patients showing NEDD9 expression enriched in the CLL proliferation centers. Blocking activity of prominent NEDD9 effectors, including AURKA and HDAC6, effectively reduced CLL cell migration and chemotaxis. Collectively, our study provides evidence for a functional role of NEDD9 in CLL pathogenesis that involves intrinsic defects in adhesion, migration and homing.

Integrative network analysis of early-stage lung adenocarcinoma identifies aurora kinase inhibition as interceptor of invasion and progression

Here we focus on the molecular characterization of clinically significant histological subtypes of early-stage lung adenocarcinoma (esLUAD), which is the most common histological subtype of lung cancer. Within lung adenocarcinoma, histology is heterogeneous and associated with tumor invasion and diverse clinical outcomes. We present a gene signature distinguishing invasive and non-invasive tumors among esLUAD. Using the gene signatures, we estimate an Invasiveness Score that is strongly associated with survival of esLUAD patients in multiple independent cohorts and with the invasiveness phenotype in lung cancer cell lines. Regulatory network analysis identifies aurora kinase as one of master regulators of the gene signature and the perturbation of aurora kinases in vitro and in a murine model of invasive lung adenocarcinoma reduces tumor invasion. Our study reveals aurora kinases as a therapeutic target for treatment of early-stage invasive lung adenocarcinoma.

ZNF655 Promotes the Progression of Glioma Through Transcriptional Regulation of AURKA

OBJECTIVES

Glioma has a high degree of malignancy, strong invasiveness, and poor prognosis, which is always a serious threat to human health. Previous studies have reported that C2H2 zinc finger (ZNF) protein is involved in the progression of various cancers. In this study, the clinical significance, biological behavior, and molecule mechanism of ZNF655 in glioma were explored.

METHODS

The expression of ZNF655 in glioma and its correlation with prognosis were analyzed through public datasets and immunohistochemical (IHC) staining. The shRNA-mediated ZNF655 knockdown was used to explore the effects of ZNF655 alteration on the phenotypes and tumorigenesis of human glioma cell lines. Chromatin immunoprecipitation (ChIP)-qPCR and luciferase reporter assays were performed to determine the potential mechanism of ZNF655 regulating Aurora kinase A (AURKA).

RESULTS

ZNF655 was abundantly expressed in glioma tissue and cell lines SHG-44 and U251. Knockdown of suppressed the progression of glioma cells, which was characterized by reduced proliferation, enhanced apoptosis, cycle repression in G2, inhibition of migration, and weakened tumorigenesis. Mechanistically, transcription factor ZNF655 activated the expression of AURKA by directly binding to the promoter of AURKA. In addition, downregulation of AURKA partially reversed the promoting effects of overexpression of ZNF655 on glioma cells.

CONCLUSIONS

ZNF655 promoted the progression of glioma by binding to the promoter of AURKA, which may be a promising target for molecular therapy.

Machine Learning-Based Analysis of Glioma Grades Reveals Co-Enrichment

Gliomas develop and grow in the brain and central nervous system. Examining glioma grading processes is valuable for improving therapeutic challenges. One of the most extensive repositories storing transcriptomics data for gliomas is The Cancer Genome Atlas (TCGA). However, such big cohorts should be processed with caution and evaluated thoroughly as they can contain batch and other effects. Furthermore, biological mechanisms of cancer contain interactions among biomarkers. Thus, we applied an interpretable machine learning approach to discover such relationships. This type of transparent learning provides not only good predictability, but also reveals co-predictive mechanisms among features. In this study, we corrected the strong and confounded batch effect in the TCGA glioma data. We further used the corrected datasets to perform comprehensive machine learning analysis applied on single-sample gene set enrichment scores using collections from the Molecular Signature Database. Furthermore, using rule-based classifiers, we displayed networks of co-enrichment related to glioma grades. Moreover, we validated our results using the external glioma cohorts. We believe that utilizing corrected glioma cohorts from TCGA may improve the application and validation of any future studies. Finally, the co-enrichment and survival analysis provided detailed explanations for glioma progression and consequently, it should support the targeted treatment.

A Microfluidics-Based Scalable Approach to Generate Extracellular Vesicles with Enhanced Therapeutic MicroRNA Loading for Intranasal Delivery to Mouse Glioblastomas

Extracellular vesicles (EVs), including exosomes and microvesicles derived from different cell sources, are used as promising nanovesicles for delivering therapeutic microRNAs (miRNAs) and drugs in cancer therapy. However, their clinical translation is limited by the quantity, size heterogeneity, and drug or small RNA loading efficiency. Herein, we developed a scalable microfluidic platform that can load therapeutic miRNAs (antimiRNA-21 and miRNA-100) and drugs while controlling the size of microfluidically processed EVs (mpEVs) using a pressure-based disruption and reconstitution process. We prepared mpEVs of optimal size using microvesicles isolated from neural stem cells engineered to overexpress CXCR4 receptor and characterized them for charge and miRNA loading efficiency. Since the delivery of therapeutic miRNAs to brain cancer is limited by the blood-brain barrier (BBB), we adopted intranasal administration of miRNA-loaded CXCR4-engineered mpEVs in orthotopic GBM mouse models and observed a consistent pattern of mpEVs trafficking across the nasal epithelia, bypassing the BBB into the intracranial compartment. In addition, the CXCR4-engineered mpEVs manifested selective tropism toward GBMs by stromal-derived factor-1 chemotaxis to deliver their miRNA cargo. The delivered miRNAs sensitized GBM cells to temozolomide, resulting in prominent tumor regression, and improved the overall survival of mice. A simple and efficient approach of packaging miRNAs in mpEVs using microfluidics, combined with a noninvasive nose-to-brain delivery route presents far-reaching potential opportunities to improve GBM therapy in clinical practice.

Viability fingerprint of glioblastoma cell lines: roles of mitotic, proliferative, and epigenetic targets

Despite the use of multimodal treatment combinations, the prognosis of glioblastoma (GB) is still poor. To prevent rapid tumor recurrence, targeted strategies for the treatment of GB are widely sought. Here, we compared the efficacy of focused modulation of a set of signaling pathways in two GB cell lines, U-251 MG and T98-G, using a panel of thirteen compounds targeting cell cycle progression, proliferation, epigenetic modifications, and DNA repair mechanism. In parallel, we tested combinations of these compounds with temozolomide and lomustine, the standard chemotherapy agents used in GB treatment. Two major trends were found: within individual compounds, the lowest IC₅₀ values were exhibited by the Aurora kinase inhibitors, whereas in the case of mixtures, the addition of DNA methyltransferase 1 inhibitor azacytidine to lomustine proved the most beneficial. The efficacy of cell cycle-targeting compounds was further augmented by combination with radiation therapy using two different treatment regimes. The potency of azacytidine and lomustine mixtures was validated using a unique assay pipeline that utilizes automated imaging and machine learning-based data analysis algorithm for assessment of cell number and DNA damage extent. Based on our results, the combination of azacytidine and lomustine should be tested in GB clinical trials.

Clinical Targeting of Altered Metabolism in High-Grade Glioma

ABSTRACT

High-grade gliomas are among the deadliest of all cancers despite standard treatments, and new therapeutic strategies are needed to improve patient outcome. Targeting the altered metabolic state of tumors with traditional chemotherapeutic agents has a history of success, and our increased understanding of cellular metabolism in the past 2 decades has reinvigorated the concept of novel metabolic therapies in brain tumors. Here we highlight metabolic alterations in advanced gliomas and their translation into clinical trials using both novel agents and already established drugs repurposed for cancer treatment in an effort to improve outcome for these deadly diseases.

The Subventricular Zone, a Hideout for Adult and Pediatric High-Grade Glioma Stem Cells

Both in adult and children, high-grade gliomas (WHO grades III and IV) account for a high proportion of death due to cancer. This poor prognosis is a direct consequence of tumor recurrences occurring within few months despite a multimodal therapy consisting of a surgical resection followed by chemotherapy and radiotherapy. There is increasing evidence that glioma stem cells (GSCs) contribute to tumor recurrences. In fact, GSCs can migrate out of the tumor mass and reach the subventricular zone (SVZ), a neurogenic niche persisting after birth. Once nested in the SVZ, GSCs can escape a surgical intervention and resist to treatments. The present review will define GSCs and describe their similarities with neural stem cells, residents of the SVZ. The architectural organization of the SVZ will be described both for humans and rodents. The migratory routes taken by GSCs to reach the SVZ and the signaling pathways involved in their migration will also be described hereafter. In addition, we will debate the advantages of the microenvironment provided by the SVZ for GSCs and how this could contribute to tumor recurrences. Finally, we will discuss the clinical relevance of the SVZ in adult GBM and pediatric HGG and the therapeutic advantages of targeting that neurogenic region in both clinical situations.

MKP1 phosphatase is recruited by CXCL12 in glioblastoma cells and plays a role in DNA strand breaks repair

Glioblastoma (GBM) is the most frequent and aggressive primary tumor in the central nervous system. Previously, the secretion of CXCL12 in the brain subventricular zones has been shown to attract GBM cells and protect against irradiation. However, the exact molecular mechanism behind this radioprotection is still unknown. Here, we demonstrate that CXCL12 modulates the phosphorylation of MAP kinases and their regulator, the nuclear MAP kinase phosphatase 1 (MKP1). We further show that MKP1 is able to decrease GBM cell death and promote DNA repair after irradiation by regulating major apoptotic players, such as Jun-N-terminal kinase, and by stabilizing the DNA repair protein RAD51. Increases in MKP1 levels caused by different corticoid treatments should be reexamined for GBM patients, particularly during their radiotherapy sessions, in order to prevent or to delay the relapses of this tumor.

The role of Aurora-A in human cancers and future therapeutics

Aurora-A is a mitotic serine/threonine-protein kinase and an oncogene. In normal cells, Aurora-A appears from G2 phase and localizes at the centrosome, where it participates in centrosome replication, isolation and maturation. Aurora-A also maintains Golgi apparatus structure and spindle assembly. Aurora-A undergoes ubiquitination-mediated degradation after the cell division phase. Aurora-A is abnormally expressed in tumor cells and promotes cell proliferation by regulating mitotic substrates, such as PP1, PLK1, TPX2, and LAST2, and affects other molecules through a non-mitotic pathway to promote cell invasion and metastasis. Some molecules in tumor cells also indirectly act on Aurora-A to regulate tumor cells. Aurora-A also mediates resistance to chemotherapy and radiotherapy and is involved in tumor immunotherapy. Clinical trials of Aurora-A molecular inhibitors are currently underway, and clinical transformation is just around the corner.

CXCL12/CXCR4 axis in the microenvironment of solid tumors: A critical mediator of metastasis

Tumors are dynamic tissue masses, so requiring continuous exposure to the host cells, nurturing them into pave a path for tumor growth and metastasis. C-X-C chemokine ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) is the key signaling for such aim. Gathering knowledge about the activity within this axis would deepen our insight into the utmost importance this signaling taken to attract and cross-connect multiple cells within the tumor microenvironment (TME) aiming for tumor progression and metastasis. The concept behind this review is to underscore the multi-tasking roles taken by CXCL12/CXCR4 signaling in tumor metastasis, and to also suggest some strategies to target the activities within this axis.

Metabolic Abnormalities in Glioblastoma and Metabolic Strategies to Overcome Treatment Resistance

Glioblastoma (GBM) is the most common and aggressive primary brain tumor and is nearly universally fatal. Targeted therapy and immunotherapy have had limited success in GBM, leaving surgery, alkylating chemotherapy and ionizing radiation as the standards of care. Like most cancers, GBMs rewire metabolism to fuel survival, proliferation, and invasion. Emerging evidence suggests that this metabolic reprogramming also mediates resistance to the standard-of-care therapies used to treat GBM. In this review, we discuss the noteworthy metabolic features of GBM, the key pathways that reshape tumor metabolism, and how inhibiting abnormal metabolism may be able to overcome the inherent resistance of GBM to radiation and chemotherapy.