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Objective(s): The present study aimed to explore the mechanisms underlying the potency of the renoprotective effect of the EtOAc fraction of Limonium duriusculum (EALD) (Plumbaginaceae) against cyclosporine A (CsA), in comparison to vitamin E (Vit. E). Materials and Methods: In the in-vivo experiment, a model of CsA-induced nephrotoxicity was established by dosing male Wistar rats with 25 mg/kg, for 14 days. The protective effect of EALD was investigated through pretreatment of rats with a dose of 200 mg/kg for 14 days, compared to the oral administration of Vit. E at 100 mg/kg. Renal function and markers of oxidative stress were then assessed. Furthermore, a complementary in-vitro study was carried out to evaluate CsA-induced endoplasmic reticulum stress (ERS) and inflammation on cell culture (3T3 cells and MCT cells) using western blot and quantitative RT-PCR. Results: Pretreatment of rats with EALD significantly attenuated the elevated levels of renal dysfunction markers (BUN, creatinine) and suppressed malondialdehyde (MDA) levels; It also significantly regulated the changes in superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxydase (GPx), and glutathione S-transferase (GST) levels as compared to Vit. E, demonstrating a more effective recovery in renal tissues. Treatment of cells with CsA was linked to the expression of ERS and inflammatory markers activating transcription factor (ATF4), inositolrequiring enzyme 1a (IRE1a), binding immunoglobulin protein (BiP), and monocyte chemoattractant protein-1 (MCP1). In contrast, pretreatment of cells with EALD resulted in a significant decrease in both ERS and inflammatory markers. Conclusion: These findings indicate the renoprotective potential of L. duriusculum, as it demonstrated the ability to ameliorate CsA-induced renal dysfunction through its distinctive antioxidant properties. [ABSTRACT FROM AUTHOR]

Local hypoxia occurs in most solid tumors and is associated with aggressive disease and therapy resistance. Widespread changes in gene expression play a critical role in the biological response to hypoxia. However, most research has focused on hypoxia‐inducible genes as opposed to those that are decreased in hypoxia. We demonstrate that chromatin accessibility is decreased in hypoxia, predominantly at gene promoters and specific pathways are impacted including DNA repair, splicing, and the R‐loop interactome. One of the genes with decreased chromatin accessibility in hypoxia was DDX5, encoding the RNA helicase, DDX5, which showed reduced expression in various cancer cell lines in hypoxic conditions, tumor xenografts, and in patient samples with hypoxic tumors. Most interestingly, we found that when DDX5 is rescued in hypoxia, replication stress and R‐loop levels accumulate further, demonstrating that hypoxia‐mediated repression of DDX5 restricts R‐loop accumulation. Together these data support the hypothesis that a critical part of the biological response to hypoxia is the repression of multiple R‐loop processing factors; however, as shown for DDX5, their role is specific and distinct. [ABSTRACT FROM AUTHOR]

Simple Summary: Glioblastomas (GBM) are aggressive brain tumors with poor prognosis that need effective treatment. GBMs are characterized by extensive cellular and molecular heterogeneity which are reflected in patient-derived cell cultures, frequently used in testing potential therapeutics. Here, we established GBM-derived cell cultures from fresh tumor specimens and characterized them at the protein and molecular levels. We confirmed the considerable intertumor heterogeneity of GBMs. As the epidermal growth factor receptor (EGFR) is a subject of common oncogenic alterations in GBM, we tested anti-EGFR therapy combined with temozolomide (first-choice medication for GBM) or with doxorubicin (common therapeutic for various solid and blood cancers). We found that GBM-derived cells were more sensitive to a combined therapy than to monotherapy, particularly cells with inactive DNA repair mechanisms. Glioblastomas (GBM) are the most common, primary brain tumors in adults. Despite advances in neurosurgery and radio- and chemotherapy, the median survival of GBM patients is 15 months. Recent large-scale genomic, transcriptomic and epigenetic analyses have shown the cellular and molecular heterogeneity of GBMs, which hampers the outcomes of standard therapies. We have established 13 GBM-derived cell cultures from fresh tumor specimens and characterized them molecularly using RNA-seq, immunoblotting and immunocytochemistry. Evaluation of proneural (OLIG2, IDH1R132H, TP53 and PDGFRα), classical (EGFR) and mesenchymal markers (CHI3L1/YKL40, CD44 and phospho-STAT3), and the expression of pluripotency (SOX2, OLIG2, NESTIN) and differentiation (GFAP, MAP2, β-Tubulin III) markers revealed the striking intertumor heterogeneity of primary GBM cell cultures. Upregulated expression of VIMENTIN, N-CADHERIN and CD44 at the mRNA/protein levels suggested increased epithelial-to-mesenchymal transition (EMT) in most studied cell cultures. The effects of temozolomide (TMZ) or doxorubicin (DOX) were tested in three GBM-derived cell cultures with different methylation status of the MGMT promoter. Amongst TMZ- or DOX-treated cultures, the strongest accumulation of the apoptotic markers caspase 7 and PARP were found in WG4 cells with methylated MGMT, suggesting that its methylation status predicts vulnerability to both drugs. As many GBM-derived cells showed high EGFR levels, we tested the effects of AG1478, an EGFR inhibitor, on downstream signaling pathways. AG1478 caused decreased levels of phospho-STAT3, and thus inhibition of active STAT3 augmented antitumor effects of DOX and TMZ in cells with methylated and intermediate status of MGMT. Altogether, our findings show that GBM-derived cell cultures mimic the considerable tumor heterogeneity, and that identifying patient-specific signaling vulnerabilities can assist in overcoming therapy resistance, by providing personalized combinatorial treatment recommendations. [ABSTRACT FROM AUTHOR]

Dendrimers are appealing scaffolds for creating carbohydrate mimics with unique multivalent cooperativity. We report here novel bola‐amphiphilic glycodendrimers bearing mannose and glucose terminals, and a hydrophobic thioacetal core responsive to reactive oxygen species. The peculiar bola‐amphiphilic feature enabled stronger binding to lectin compared to conventional amphiphiles. In addition, these dendrimers are able to target mannose receptors and glucose transporters expressed at the surface of cells, thus allowing effective and specific cellular uptake. This highlights their great promise for targeted delivery. [ABSTRACT FROM AUTHOR]

Simple Summary: The extent of tumour oxygenation is crucial for glioblastoma progression and the effectiveness of radio- and chemotherapy. Patient-derived in vitro cell cultures are the mainstay of molecular biology research, the discovery of new therapeutic targets, and drug testing. Therefore, mirroring as many aspects of in vivo settings as possible, including oxygen concentration, is desired. Here we analyse the effect of oxygen tension on the transcriptome of numerous patient-derived GBM cells and demonstrate that cells cultured in lowered oxygen tension express more genes indicative of higher levels of hypoxia, metabolic adaptation, stemness and tumour progression than cells growing in standard, atmospheric oxygen concentration. The same transcriptomic pattern was also found in primary GBM samples. Its specificity for GBMs was confirmed using the public TCGA dataset. Our data strongly argue for the benefit of lower oxygen tension during culturing of patient-derived GBM cells to preserve oxygen-sensitive pathways in GBM. The proposed approach better mimics certain aspects of GBM pathophysiology than traditional cultures and may advance GBM research in finding a cure. Despite numerous efforts aiming to characterise glioblastoma pathology (GBM) and discover new therapeutic strategies, GBM remains one of the most challenging tumours to treat. Here we propose the optimisation of in vitro culturing of GBM patient-derived cells, namely the establishment of GBM-derived cultures and their maintenance at oxygen tension mimicking oxygenation conditions occurring within the tumour. To globally analyse cell states, we performed the transcriptome analysis of GBM patient-derived cells kept as spheroids in serum-free conditions at the reduced oxygen tension (5% O2), cells cultured at atmospheric oxygen (20% O2), and parental tumour. Immune cells present in the tumour were depleted, resulting in the decreased expression of the immune system and inflammation-related genes. The expression of genes promoting cell proliferation and DNA repair was higher in GBM cell cultures when compared to the relevant tumour sample. However, lowering oxygen tension to 5% did not affect the proliferation rate and expression of cell cycle and DNA repair genes in GBM cell cultures. Culturing GBM cells at 5% oxygen was sufficient to increase the expression of specific stemness markers, particularly the PROM1 gene, without affecting neural cell differentiation markers. GBM spheroids cultured at 5% oxygen expressed higher levels of hypoxia-inducible genes, including those encoding glycolytic enzymes and pro-angiogenic factors. The genes up-regulated in cells cultured at 5% oxygen had higher expression in parental GBMs compared to that observed in 20% cell cultures, suggesting the preservation of the hypoxic component of GBM transcriptome at 5% oxygen and its loss in standard culture conditions. Evaluation of expression of those genes in The Cancer Genome Atlas dataset comprising samples of normal brain tissue, lower-grade gliomas and GBMs indicated the expression pattern of the indicated genes was specific for GBM. Moreover, GBM cells cultured at 5% oxygen were more resistant to temozolomide, the chemotherapeutic used in GBM therapy. The presented comparison of GBM cultures maintained at high and low oxygen tension together with analysis of tumour transcriptome indicates that lowering oxygen tension during cell culture may more allegedly reproduce tumour cell behaviour within GBM than standard culture conditions (e.g., atmospheric oxygen tension). Low oxygen culture conditions should be considered as a more appropriate model for further studies on glioblastoma pathology and therapy. [ABSTRACT FROM AUTHOR]

Immunotherapies with immune checkpoint inhibitors or adoptive cell transfer have become powerful tools to treat cancer. These treatments act via overcoming or alleviating tumor-induced immunosuppression, thereby enabling effective tumor clearance. Glioblastoma (GBM) represents the most aggressive, primary brain tumor that remains refractory to the benefits of immunotherapy. The immunosuppressive immune tumor microenvironment (TME), genetic and cellular heterogeneity, and disorganized vasculature hinder drug delivery and block effector immune cell trafficking and activation, consequently rendering immunotherapy ineffective. Within the TME, the mutual interactions between tumor, immune and endothelial cells result in the generation of positive feedback loops, which intensify immunosuppression and support tumor progression. We focus here on the role of aberrant tumor vasculature and how it can mediate hypoxia and immunosuppression. We discuss how immune cells use immunosuppressive signaling for tumor progression and contribute to the development of resistance to immunotherapy. Finally, we assess how a positive feedback loop between vascular normalization and immune cells, including myeloid cells, could be targeted by combinatorial therapies with immune checkpoint blockers and sensitize the tumor to immunotherapy. [ABSTRACT FROM AUTHOR]

Simple Summary: Malignant brain tumors present an enormous challenge due to their genetic heterogeneity, and the difficulties in accessing them impede a precise diagnosis. Numerous genetic alterations have been described, and some of them can assist in personalized therapy for glioma patients. Brain biopsy is an invasive procedure with potentially deleterious complications. Liquid biopsy from a patient's plasma may provide a less invasive method for diagnosis and personalized therapy selection. We performed targeted next-generation sequencing of tumors and circulating cell-free DNA (ccfDNA) from 84 brain tumor patients. We detected tumor-specific genetic alterations in ccfDNA in 5 out of 80 glioma patients and potentially pathogenic alterations in ccfDNA from the plasma of 29 out of 80 glioma patients. Despite a low efficacy, with further improvements, the detection of genetic alterations in ccfDNA holds promise for noninvasive diagnosis, which may revolutionize personalized therapy for these deadly tumors. Malignant gliomas are the most frequent primary brain tumors in adults. They are genetically heterogenous and invariably recur due to incomplete surgery and therapy resistance. Circulating tumor DNA (ctDNA) is a component of circulating cell-free DNA (ccfDNA) and represents genetic material that originates from the primary tumor or metastasis. Brain tumors are frequently located in the eloquent brain regions, which makes biopsy difficult or impossible due to severe postoperative complications. The analysis of ccfDNA from a patient's blood presents a plausible and noninvasive alternative. In this study, freshly frozen tumors and corresponding blood samples were collected from 84 brain tumor patients and analyzed by targeted next-generation sequencing (NGS). The cohort included 80 glioma patients, 2 metastatic cancer patients, and 2 primary CNS lymphoma (PCNSL) patients. We compared the pattern of genetic alterations in the tumor DNA (tDNA) with that of ccfDNA. The implemented technical improvements in quality control and library preparation allowed for the detection of ctDNA in 8 out of 84 patients, including 5 out of 80 glioma patients. In 32 out of 84 patients, we found potentially pathogenic genetic alterations in ccfDNA that were not detectable in tDNA. While sequencing ccfDNA from plasma has a low efficacy as a diagnostic tool for glioma patients, we concluded that further improvements in sample processing and library preparation can make liquid biopsy a valuable diagnostic tool for glioma patients. [ABSTRACT FROM AUTHOR]

When imaging through turbid media, objects are often blurred by scattered light. An optical collimator (i.e., an angular filter array) improves images by accepting only photons propagating within a narrow solid angle about the direction of the incident light. These photons are expected to participate in a limited number of small-angle scattering events, maintaining their original propagation direction and, finally, contributing to the development of a faithful image of an object within a turbid medium. The collimation method, also referred to as angular domain imaging (ADI), applies to a see-through configuration where the incident collimated light beam can be aligned with the collimator in a transillumination mode of operation. In this paper, we present angular domain optical projection tomography (ADOPT), a method that can extract depth information of optical contrast in turbid media with high longitudinal resolution based on ADI technology. The resolution of the ADI system has been tested over various depths in a 5 cm optical cuvette using a resolution target suspended in a homogeneous turbid medium. The ADOPT system reconstructed images from a series of angular domain projections collected at angular intervals. The system was used to measure the attenuation of an absorbing target in transmission mode (t-ADOPT) and to measure the light emitting from a fluorescent target (f-ADOPT). Tissue-mimicking phantoms were used to validate the performance of the method. In the t-ADOPT configuration, a background scattered light estimation and subtraction methodology was introduced to improve the imaging contrast. A target consisting of two graphite rods (0.9 mm diameter) was suspended in the cuvette by a rotation stage. An Indocyanine Green-filled glass rod was used as an imaging target in the f-ADOPT arrangement. The target was placed in a manner such that the line of laser light was perpendicular to the longitudinal axis of the rods. Several projections were collected at increments of 1.8[degrees] and compiled into a sinogram. A transverse image was reconstructed from the sinogram by using filtered backprojection and image contrast was improved by experimental scatter measurements using a wedge prism and an image processing algorithm. The submillimeter target embedded in a 2 cm thick scattering medium (reduced scattering coefficient [is less than or equal to] 2.4 [cm.sup.-1]) was discernable in both the sinograms and the reconstructed images. In the f-ADOPT system, fluorescent line targets < 1 cm in diameter embedded in a 2 cm thick scattering medium (reduced scattering coefficient [is less than or equal to] 0.8 [cm.sup.-1]) were discernable in both the sinograms and the reconstructed images. The proposed method could be used as the basis to construct an optical tomographic scanner for simultaneous absorption and fluorescence-based imaging of biological specimens (i.e., up to 7mm across). OCIS codes: 110.0113, 120.1680, 120.5820.

Simple Summary: In recent years, many studies have shown the importance of TAM kinases in both normal and neoplastic cells. In this review, we present and discuss the role of the TAM family (AXL, MERTK, TYRO3) of receptor tyrosine kinases (RTKs) as a dual target in cancer, due to their intrinsic roles in tumour cell survival, migration, chemoresistance, and their immunosuppressive roles in the tumour microenvironment. This review presents the potential of TAMs as emerging therapeutic targets in cancer treatment, focusing on the distinct structures of TAM receptor tyrosine kinases. We analyse and compare different strategies of TAM inhibition, for a full perspective of current and future battlefields in the war with cancer. Receptor tyrosine kinases (RTKs) are transmembrane receptors that bind growth factors and cytokines and contain a regulated kinase activity within their cytoplasmic domain. RTKs play an important role in signal transduction in both normal and malignant cells, and their encoding genes belong to the most frequently affected genes in cancer cells. The TAM family proteins (TYRO3, AXL, and MERTK) are involved in diverse biological processes: immune regulation, clearance of apoptotic cells, platelet aggregation, cell proliferation, survival, and migration. Recent studies show that TAMs share overlapping functions in tumorigenesis and suppression of antitumour immunity. MERTK and AXL operate in innate immune cells to suppress inflammatory responses and promote an immunosuppressive tumour microenvironment, while AXL expression correlates with epithelial-to-mesenchymal transition, metastasis, and motility in tumours. Therefore, TAM RTKs represent a dual target in cancer due to their intrinsic roles in tumour cell survival, migration, chemoresistance, and their immunosuppressive roles in the tumour microenvironment (TME). In this review, we discuss the potential of TAMs as emerging therapeutic targets in cancer treatment. We critically assess and compare current approaches to target TAM RTKs in solid tumours and the development of new inhibitors for both extra- and intracellular domains of TAM receptor kinases. [ABSTRACT FROM AUTHOR]