Interstitial guidance of cancer invasion

Risk Factors Involved in the Blood (Leukocyte-Depleted Suspended Red Blood Cells and Plasma) Transfusion During Glioma Operations

Background

The use of blood transfusion in surgery is increasing, and the blood supply is getting tighter. The number of glioma surgeries is increasing year by year, and reports of studies on blood transfusion in glioma surgery are relatively rare.

Purpose

To investigate the risk factors for intraoperative blood (leukocyte-depleted suspended red blood cells and plasma) transfusion in glioma patients.

Patients and Methods

We retrospectively analyzed the data of 200 glioma patients who had been operated on in a general teaching hospital in China from January 1, 2018 to March 31, 2022. In terms of whether blood transfusion (leukocyte-depleted suspended red blood cells and plasma) was used intraoperatively, patients were divided into a transfusion group (n=82) and a non-transfusion group (n=118). Multivariate Logistic regression analysis was conducted to identify the risk factors for intraoperative blood transfusion.

Results

The rate of intraoperative transfusion rate in the 200 glioma patients was 41%. Multivariate Logistic regression analysis showed that operation time, intraoperative blood loss ≥500 mL, vascular involvement, and the extent of tumor resection (total resection) were independent risk factors for intraoperative blood transfusion (P<0.05). Patient height was a protective factor against intraoperative blood transfusion (P<0.05).

Conclusion

The risk of intraoperative blood transfusion was higher in glioma patients with longer operation time, more intraoperative blood loss, vascular involvement, and total tumor resection. Clinically, efforts should be made to avoid these transfusion-related risk factors to minimize the risk of blood transfusion in patients.

Confined cell migration along extracellular matrix space in vivo

Collective migration of cancer cells is often interpreted using concepts derived from the physics of active matter, but the experimental evidence is mostly restricted to observations made in vitro. Here, we study collective invasion of metastatic cancer cells injected into the mouse deep dermis using intravital multiphoton microscopy combined with a skin window technique and three-dimensional quantitative image analysis. We observe a multicellular but low-cohesive migration mode characterized by rotational patterns which self-organize into antiparallel persistent tracks with orientational nematic order. We analyze the deformations induced by the cells in the extracellular matrix and find broadly distributed strain bands with a prevalence of compression. A model of active nematic hydrodynamics is able to describe several statistical features of the experimentally observed flow, suggesting that collective cancer cell invasion can be interpreted as a nematic active fluid in the turbulent regime. Our results help elucidate the migration patterns of cancer cells in vivo and provide quantitative guidance for the development of realistic in vitro and in silico models for collective cell migration.

Heterogeneity of intracellular calcium signaling of glioblastoma cells depends on intratumoral location and migration state

Background

Glioblastoma (GB), is an incurable brain tumor characterized by extreme malignancy and invasiveness, and the cellular mechanisms underlying such a severe phenotype are not completely understood. Although calcium (Ca2+) plays an important part in tumor proliferation and infiltration, it remains unclear whether Ca2+ signaling in GB cells is related to its location within the tumor and on the infiltrative potential of the cells.

Methods

In this study, we developed a stably transfected GL261 cell line that coexpresses a red fluorescent protein for actin cytoskeleton staining and the intracellular Ca2+ sensor, GCaMP6s. By means of intravital 2-photon imaging, we have characterized the morphological and functional properties of cells at different locations within the tumor.

Results

Our results showed that cells located at the tumor core are densely packed and rounded in shape, contrasting sharply with the polarized morphology observed in the peripheral cells. This anatomical heterogeneity corresponded to notable variations of the physiological phenotype: cells at the tumor core displayed low Ca2+ activity and very limited motility, while peripheral cells displayed intense Ca2+ activity and increased migration rates. Moreover, peripheral cells formed a cellular ensemble characterized by synchronized Ca2+ activity accompanied by a directionally biased collective motility.

Conclusions

These findings suggest that GB cells manifest activity patterns depending upon their spatial location within the tumor and that these correlate with their migration.

Insights from a multiscale framework on metabolic rate variation driving glioblastoma multiforme growth and invasion

Non-physiological levels of oxygen and nutrients within the tumors result in heterogeneous cell populations that exhibit distinct necrotic, hypoxic, and proliferative zones. Among these zonal cellular properties, metabolic rates strongly affect the overall growth and invasion of tumors. Here, we report on a hybrid discrete-continuum (HDC) mathematical framework that uses metabolic data from a biomimetic two-dimensional (2D) in-vitro cancer model to predict three-dimensional (3D) behaviour of in-vitro human glioblastoma (hGB). The mathematical model integrates modules of continuum, discrete, and neurons. Results indicated that the HDC model is capable of quantitatively predicting growth, invasion length, and the asymmetric finger-type invasion pattern in in-vitro hGB tumors. Additionally, the model could predict the reduction in invasion length of hGB tumoroids in response to temozolomide (TMZ). This model has the potential to incorporate additional modules, including immune cells and signaling pathways governing cancer/immune cell interactions, and can be used to investigate targeted therapies.

Glioma-Derived Exosomes and Their Application as Drug Nanoparticles

Glioblastoma Multiforme (GBM) is the most aggressive primary tumor of the Central Nervous System (CNS) with a low survival rate. The malignancy of GBM is sustained by a bidirectional crosstalk between tumor cells and the Tumor Microenvironment (TME). This mechanism of intercellular communication is mediated, at least in part, by the release of exosomes. Glioma-Derived Exosomes (GDEs) work, indeed, as potent signaling particles promoting the progression of brain tumors by inducing tumor proliferation, invasion, migration, angiogenesis and resistance to chemotherapy or radiation. Given their nanoscale size, exosomes can cross the blood-brain barrier (BBB), thus becoming not only a promising biomarker to predict diagnosis and prognosis but also a therapeutic target to treat GBM. In this review, we describe the structural and functional characteristics of exosomes and their involvement in GBM development, diagnosis, prognosis and treatment. In addition, we discuss how exosomes can be modified to be used as a therapeutic target/drug delivery system for clinical applications.

Dynamics of actinotrichia, fibrous collagen structures in zebrafish fin tissues, unveiled by novel fluorescent probes

Collagen fibers provide physical support to animal tissues by orienting in the correct position and at optimal density. Actinotrichia are thick collagen fibers that are present at the tips of fish fins and serve as scaffolds for bone formation. The arrangement and density of actinotrichia must be constantly maintained with a high degree of regularity to form spatial patterns in the fin bones, but the mechanisms of this process are largely unknown. To address this issue, we first identified two fluorescent probes that can stain actinotrichia clearly in vivo. Using these probes and time-lapse observation of actinotrichia synthesized at different growth stages, we revealed the following previously unknown dynamics of actinotrichia. (i) Actinotrichia do not stay stationary at the place where they are produced; instead, they move towards the dorsal area during the notochord bending and (ii) move towards the distal tip during the fin growth. (iii) Actinotrichia elongate asymmetrically as new collagen is added at the proximal side. (iv) Density is maintained by the insertion of new actinotrichia. (v) Actinotrichia are selectively degraded by osteoclasts. These findings suggest that the regular arrangement of actinotrichia is the outcome of multiple dynamic processes.

N-cadherin dynamically regulates pediatric glioma cell migration in complex environments

Pediatric high-grade gliomas are highly invasive and essentially incurable. Glioma cells migrate between neurons and glia, along axon tracts, and through extracellular matrix surrounding blood vessels and underlying the pia. Mechanisms that allow adaptation to such complex environments are poorly understood. N-cadherin is highly expressed in pediatric gliomas and associated with shorter survival. We found that intercellular homotypic N-cadherin interactions differentially regulate glioma migration according to the microenvironment, stimulating migration on cultured neurons or astrocytes but inhibiting invasion into reconstituted or astrocyte-deposited extracellular matrix. N-cadherin localizes to filamentous connections between migrating leader cells but to epithelial-like junctions between followers. Leader cells have more surface and recycling N-cadherin, increased YAP1/TAZ signaling, and increased proliferation relative to followers. YAP1/TAZ signaling is dynamically regulated as leaders and followers change position, leading to altered N-cadherin levels and organization. Together, the results suggest that pediatric glioma cells adapt to different microenvironments by regulating N-cadherin dynamics and cell-cell contacts.

Functionalized liposomes: an enticing nanocarrier for management of glioma

Glioma is one of the most severe central nervous systems (CNS)-specific tumors, with rapidly growing malignant glial cells accounting for roughly half of all brain tumors and having a poor survival rate ranging from 12 to 15 months. Despite being the most often used technique for glioma therapy, conventional chemotherapy suffers from low permeability of the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB) to anticancer drugs. When it comes to nanocarriers, liposomes are thought of as one of the most promising nanocarrier systems for glioma treatment. However, owing to BBB tight junctions, non-targeted liposomes, which passively accumulate in most cancer cells primarily via the increased permeability and retention effect (EPR), would not be suitable for glioma treatment. The surface modification of liposomes with various active targeting ligands has shown encouraging outcomes in the recent times by allowing various chemotherapy drugs to pass across the BBB and BBTB and enter glioma cells. This review article introduces by briefly outlining the landscape of glioma, its classification, and some of the pathogenic causes. Further, it discusses major barriers for delivering drugs to glioma such as the BBB, BBTB, and tumor microenvironment. It further discusses modified liposomes such as long-acting circulating liposomes, actively targeted liposomes, stimuli responsive liposomes. Finally, it highlighted the limitations of liposomes in the treatment of glioma and the various actively targeted liposomes undergoing clinical trials for the treatment of glioma.

Spatiotemporal Insights into Glioma Oncostream Dynamics: Unraveling Formation, Stability, and Disassembly Pathways

Glioblastoma (GBM) remains a challenge in Neuro-oncology, with a poor prognosis showing only a 5% survival rate beyond two years. This is primarily due to its aggressiveness and intra-tumoral heterogeneity, which limits complete surgical resection and reduces the efficacy of existing treatments. The existence of oncostreams-neuropathological structures comprising aligned spindle-like cells from both tumor and non-tumor origins- is discovered earlier. Oncostreams are closely linked to glioma aggressiveness and facilitate the spread into adjacent healthy brain tissue. A unique molecular signature intrinsic to oncostreams, with overexpression of key genes (i.e., COL1A1, ACTA2) that drive the tumor's mesenchymal transition and malignancy is also identified. Pre-clinical studies on genetically engineered mouse models demonstrated that COL1A1 inhibition disrupts oncostreams, modifies TME, reduces mesenchymal gene expression, and extends survival. An in vitro model using GFP+ NPA cells to investigate how various treatments affect oncostream dynamics is developed. Analysis showed that factors such as cell density, morphology, neurotransmitter agonists, calcium chelators, and cytoskeleton-targeting drugs influence oncostream formation. This data illuminate the patterns of glioma migration and suggest anti-invasion strategies that can improve GBM patient outcomes when combined with traditional therapies. This work highlights the potential of targeting oncostreams to control glioma invasion and enhance treatment efficacy.

Confinement in fibrous environments positions and orients mitotic spindles

Accurate positioning of the mitotic spindle within the rounded cell body is critical to physiological maintenance. Adherent mitotic cells encounter confinement from neighboring cells or the extracellular matrix (ECM), which can cause rotation of mitotic spindles and, consequently, titling of the metaphase plate (MP). To understand the positioning and orientation of mitotic spindles under confinement by fibers (ECM-confinement), we use flexible ECM-mimicking nanofibers that allow natural rounding of the cell body while confining it to differing levels. Rounded mitotic bodies are anchored in place by actin retraction fibers (RFs) originating from adhesion clusters on the ECM-mimicking fibers. We discover the extent of ECM-confinement patterns RFs in 3D: triangular and band-like at low and high confinement, respectively. A stochastic Monte-Carlo simulation of the centrosome (CS), chromosome (CH), membrane interactions, and 3D arrangement of RFs on the mitotic body recovers MP tilting trends observed experimentally. Our mechanistic analysis reveals that the 3D shape of RFs is the primary driver of the MP rotation. Under high ECM-confinement, the fibers can mechanically pinch the cortex, causing the MP to have localized deformations at contact sites with fibers. Interestingly, high ECM-confinement leads to low and high MP tilts, which mechanistically depend upon the extent of cortical deformation, RF patterning, and MP position. We identify that cortical deformation and RFs work in tandem to limit MP tilt, while asymmetric positioning of MP leads to high tilts. Overall, we provide fundamental insights into how mitosis may proceed in fibrous ECM-confining microenvironments in vivo.

Small Cajal Body-Specific RNA12 Promotes Carcinogenesis through Modulating Extracellular Matrix Signaling in Bladder Cancer

Background: Small Cajal body-specific RNAs (scaRNAs) are a specific subset of small nucleolar RNAs (snoRNAs) that have recently emerged as pivotal contributors in diverse physiological and pathological processes. However, their defined roles in carcinogenesis remain largely elusive. This study aims to explore the potential function and mechanism of SCARNA12 in bladder cancer (BLCA) and to provide a theoretical basis for further investigations into the biological functionalities of scaRNAs. Materials and Methods: TCGA, GEO and GTEx data sets were used to analyze the expression of SCARNA12 and its clinicopathological significance in BLCA. Quantitative real-time PCR (qPCR) and in situ hybridization were applied to validate the expression of SCARNA12 in both BLCA cell lines and tissues. RNA sequencing (RNA-seq) combined with bioinformatics analyses were conducted to reveal the changes in gene expression patterns and functional pathways in BLCA patients with different expressions of SCARNA12 and T24 cell lines upon SCARNA12 knockdown. Single-cell mass cytometry (CyTOF) was then used to evaluate the tumor-related cell cluster affected by SCARNA12. Moreover, SCARNA12 was stably knocked down in T24 and UMUC3 cell lines by lentivirus-mediated CRISPR/Cas9 approach. The biological effects of SCARNA12 on the proliferation, clonogenic, migration, invasion, cell apoptosis, cell cycle, and tumor growth were assessed by in vitro MTT, colony formation, wound healing, transwell, flow cytometry assays, and in vivo nude mice xenograft models, respectively. Finally, a chromatin isolation by RNA purification (ChIRP) experiment was further conducted to delineate the potential mechanisms of SCARNA12 in BLCA. Results: The expression of SCARNA12 was significantly up-regulated in both BLCA tissues and cell lines. RNA-seq data elucidated that SCARAN12 may play a potential role in cell adhesion and extracellular matrix (ECM) related signaling pathways. CyTOF results further showed that an ECM-related cell cluster with vimentin+, CD13+, CD44+, and CD47+ was enriched in BLCA patients with high SCARNA12 expression. Additionally, SCARNA12 knockdown significantly inhibited the proliferation, colony formation, migration, and invasion abilities in T24 and UMUC3 cell lines. SCARNA12 knockdown prompted cell arrest in the G0/G1 and G2/M phase and promoted apoptosis in T24 and UMUC3 cell lines. Furthermore, SCARNA12 knockdown could suppress the in vivo tumor growth in nude mice. A ChIRP experiment further suggested that SCARNA12 may combine transcription factors H2AFZ to modulate the transcription program and then affect BLCA progression. Conclusions: Our study is the first to propose aberrant alteration of SCARNA12 and elucidate its potential oncogenic roles in BLCA via the modulation of ECM signaling. The interaction of SCARNA12 with the transcriptional factor H2AFZ emerges as a key contributor to the carcinogenesis and progression of BLCA. These findings suggest SCARNA12 may serve as a diagnostic biomarker and potential therapeutic target for the treatment of BLCA.

N-cadherin dynamically regulates pediatric glioma cell migration in complex environments

Pediatric high-grade gliomas are highly invasive and essentially incurable. Glioma cells migrate between neurons and glia, along axon tracts, and through extracellular matrix surrounding blood vessels and underlying the pia. Mechanisms that allow adaptation to such complex environments are poorly understood. N-cadherin is highly expressed in pediatric gliomas and associated with shorter survival. We found that inter-cellular homotypic N-cadherin interactions differentially regulate glioma migration according to the microenvironment, stimulating migration on cultured neurons or astrocytes but inhibiting invasion into reconstituted or astrocyte-deposited extracellular matrix. N-cadherin localizes to filamentous connections between migrating leader cells but to epithelial-like junctions between followers. Leader cells have more surface and recycling N-cadherin, increased YAP1/TAZ signaling, and increased proliferation relative to followers. YAP1/TAZ signaling is dynamically regulated as leaders and followers change position, leading to altered N-cadherin levels and organization. Together, the results suggest that pediatric glioma cells adapt to different microenvironments by regulating N-cadherin dynamics and cell-cell contacts.

Individual glioblastoma cells harbor both proliferative and invasive capabilities during tumor progression

BACKGROUND

Glioblastomas are characterized by aggressive and infiltrative growth, and by striking heterogeneity. The aim of this study was to investigate whether tumor cell proliferation and invasion are interrelated, or rather distinct features of different cell populations.

METHODS

Tumor cell invasion and proliferation were longitudinally determined in real-time using 3D in vivo 2-photon laser scanning microscopy over weeks. Glioblastoma cells expressed fluorescent markers that permitted the identification of their mitotic history or their cycling versus non-cycling cell state.

RESULTS

Live reporter systems were established that allowed us to dynamically determine the invasive behavior, and previous or actual proliferation of distinct glioblastoma cells, in different tumor regions and disease stages over time. Particularly invasive tumor cells that migrated far away from the main tumor mass, when followed over weeks, had a history of marked proliferation and maintained their proliferative capacity during brain colonization. Infiltrating cells showed fewer connections to the multicellular tumor cell network, a typical feature of gliomas. Once tumor cells colonized a new brain region, their phenotype progressively transitioned into tumor microtube-rich, interconnected, slower-cycling glioblastoma cells. Analysis of resected human glioblastomas confirmed a higher proliferative potential of tumor cells from the invasion zone.

CONCLUSIONS

The detection of glioblastoma cells that harbor both particularly high proliferative and invasive capabilities during brain tumor progression provides valuable insights into the interrelatedness of proliferation and migration-2 central traits of malignancy in glioma. This contributes to our understanding of how the brain is efficiently colonized in this disease.

The ECM and tissue architecture are major determinants of early invasion mediated by E-cadherin dysfunction

Germline mutations of E-cadherin cause Hereditary Diffuse Gastric Cancer (HDGC), a highly invasive cancer syndrome characterised by the occurrence of diffuse-type gastric carcinoma and lobular breast cancer. In this disease, E-cadherin-defective cells are detected invading the adjacent stroma since very early stages. Although E-cadherin loss is well established as a triggering event, other determinants of the invasive process persist largely unknown. Herein, we develop an experimental strategy that comprises in vitro extrusion assays using E-cadherin mutants associated to HDGC, as well as mathematical models epitomising epithelial dynamics and its interaction with the extracellular matrix (ECM). In vitro, we verify that E-cadherin dysfunctional cells detach from the epithelial monolayer and extrude basally into the ECM. Through phase-field modelling we demonstrate that, aside from loss of cell-cell adhesion, increased ECM attachment further raises basal extrusion efficiency. Importantly, by combining phase-field and vertex model simulations, we show that the cylindrical structure of gastric glands strongly promotes the cell's invasive ability. Moreover, we validate our findings using a dissipative particle dynamics simulation of epithelial extrusion. Overall, we provide the first evidence that cancer cell invasion is the outcome of defective cell-cell linkages, abnormal interplay with the ECM, and a favourable 3D tissue structure.

Bayesian Inference of Tissue Heterogeneity for Individualized Prediction of Glioma Growth

Reliably predicting the future spread of brain tumors using imaging data and on a subject-specific basis requires quantifying uncertainties in data, biophysical models of tumor growth, and spatial heterogeneity of tumor and host tissue. This work introduces a Bayesian framework to calibrate the two-/three-dimensional spatial distribution of the parameters within a tumor growth model to quantitative magnetic resonance imaging (MRI) data and demonstrates its implementation in a pre-clinical model of glioma. The framework leverages an atlas-based brain segmentation of grey and white matter to establish subject-specific priors and tunable spatial dependencies of the model parameters in each region. Using this framework, the tumor-specific parameters are calibrated from quantitative MRI measurements early in the course of tumor development in four rats and used to predict the spatial development of the tumor at later times. The results suggest that the tumor model, calibrated by animal-specific imaging data at one time point, can accurately predict tumor shapes with a Dice coefficient 0.89. However, the reliability of the predicted volume and shape of tumors strongly relies on the number of earlier imaging time points used for calibrating the model. This study demonstrates, for the first time, the ability to determine the uncertainty in the inferred tissue heterogeneity and the model-predicted tumor shape.

Scale-free correlations and potential criticality in weakly ordered populations of brain cancer cells

Collective behavior spans several orders of magnitude of biological organization, from cell colonies to flocks of birds. We used time-resolved tracking of individual glioblastoma cells to investigate collective motion in an ex vivo model of glioblastoma. At the population level, glioblastoma cells display weakly polarized motion in the (directional) velocities of single cells. Unexpectedly, fluctuations in velocities are correlated over distances many times the size of a cell. Correlation lengths scale linearly with the maximum end-to-end length of the population, indicating that they are scale-free and lack a characteristic decay scale other than the size of the system. Last, a data-driven maximum entropy model captures statistical features of the experimental data with only two free parameters: the effective length scale (nc) and strength (J) of local pairwise interactions between tumor cells. These results show that glioblastoma assemblies exhibit scale-free correlations in the absence of polarization, suggesting that they may be poised near a critical point.

Evaluating glioblastoma tumour sphere growth and migration in interaction with astrocytes using 3D collagen-hyaluronic acid hydrogels

Glioblastoma (GB) is an astrocytic brain tumour with a low survival rate, partly because of its highly invasive nature. The GB tumour microenvironment (TME) includes its extracellular matrix (ECM), a variety of brain cell types, unique anatomical structures, and local mechanical cues. As such, researchers have attempted to create biomaterials and culture models that mimic features of TME complexity. Hydrogel materials have been particularly popular because they enable 3D cell culture and mimic TME mechanical properites and chemical composition. Here, we used a 3D collagen I-hyaluronic acid hydrogel material to explore interactions between GB cells and astrocytes, the normal cell type from which GB likely derives. We demonstrate three different spheroid culture configurations, including GB multi-spheres (i.e., GB and astrocyte cells in spheroid co-culture), GB-only mono-spheres cultured with astrocyte-conditioned media, and GB-only mono-spheres cultured with dispersed live or fixed astrocytes. Using U87 and LN229 GB cell lines and primary human astrocytes, we investigated material and experiment variability. We then used time-lapse fluorescence microscopy to measure invasive potential by characterizing the sphere size, migration capacity, and weight-averaged migration distance in these hydrogels. Finally, we developed methods to extract RNA for gene expression analysis from cells cultured in hydrogels. U87 and LN229 cells displayed different migration behaviors. U87 migration occurred primarily as single cells and was reduced with higher numbers of astrocytes in both multi-sphere and mono-sphere plus dispersed astrocyte cultures. In contrast, LN229 migration exhibited features of collective migration and was increased in monosphere plus dispersed astrocyte cultures. Gene expression studies indicated that the most differentially expressed genes in these co-cultures were CA9, HLA-DQA1, TMPRSS2, FPR1, OAS2, and KLRD1. Most differentially expressed genes were related to immune response, inflammation, and cytokine signalling, with greater influence on U87 than LN229. These data show that 3D in vitro hydrogel co-culture models can be used to reveal cell line specific differences in migration and to study differential GB-astrocyte crosstalk.

Single-cell transcriptomics in ovarian cancer identify a metastasis-associated cell cluster overexpressed RAB13

BACKGROUND

Metastasis, the leading cause of cancer-related death in patients diagnosed with ovarian cancer (OC), is a complex process that involves multiple biological effects. With the continuous development of sequencing technology, single-cell sequence has emerged as a promising strategy to understand the pathogenesis of ovarian cancer.

METHODS

Through integrating 10 × single-cell data from 12 samples, we developed a single-cell map of primary and metastatic OC. By copy-number variations analysis, pseudotime analysis, enrichment analysis, and cell-cell communication analysis, we explored the heterogeneity among OC cells. We performed differential expression analysis and high dimensional weighted gene co-expression network analysis to identify the hub genes of C4. The effects of RAB13 on OC cell lines were validated in vitro.

RESULTS

We discovered a cell subcluster, referred to as C4, that is closely associated with metastasis and poor prognosis in OC. This subcluster correlated with an epithelial-mesenchymal transition (EMT) and angiogenesis signature and RAB13 was identified as the key marker of it. Downregulation of RAB13 resulted in a reduction of OC cells migration and invasion. Additionally, we predicted several potential drugs that might inhibit RAB13.

CONCLUSIONS

Our study has identified a cell subcluster that is closely linked to metastasis in OC, and we have also identified RAB13 as its hub gene that has great potential to become a new therapeutic target for OC.

From cells to organoids: The evolution of blood-brain barrier technology for modelling drug delivery in brain cancer

Brain cancer remains the deadliest cancer. The blood-brain barrier (BBB) is impenetrable to most drugs and is a complex 3D network of multiple cell types including endothelial cells, astrocytes, and pericytes. In brain cancers, the BBB becomes disrupted during tumor progression and forms the blood-brain tumor barrier (BBTB). To advance therapeutic development, there is a critical need for physiologically relevant BBB in vitro models. 3D cell systems are emerging as valuable preclinical models to accelerate discoveries for diseases. Given the versatility and capability of 3D cell models, their potential for modelling the BBB and BBTB is reviewed. Technological advances of BBB models and challenges of in vitro modelling the BBTB, and application of these models as tools for assessing therapeutics and nano drug delivery, are discussed. Quantitative, in vitro BBB models that are predictive of effective brain cancer therapies will be invaluable for accelerating advancing new treatments to the clinic.

A live-cell platform to isolate phenotypically defined subpopulations for spatial multi-omic profiling

Numerous techniques have been employed to deconstruct the heterogeneity observed in normal and diseased cellular populations, including single cell RNA sequencing, in situ hybridization, and flow cytometry. While these approaches have revolutionized our understanding of heterogeneity, in isolation they cannot correlate phenotypic information within a physiologically relevant live-cell state, with molecular profiles. This inability to integrate a historical live-cell phenotype, such as invasiveness, cell:cell interactions, and changes in spatial positioning, with multi-omic data, creates a gap in understanding cellular heterogeneity. We sought to address this gap by employing lab technologies to design a detailed protocol, termed Spatiotemporal Genomics and Cellular Analysis (SaGA), for the precise imaging-based selection, isolation, and expansion of phenotypically distinct live-cells. We begin with cells stably expressing a photoconvertible fluorescent protein and employ live cell confocal microscopy to photoconvert a user-defined single cell or set of cells displaying a phenotype of interest. The total population is then extracted from its microenvironment, and the optically highlighted cells are isolated using fluorescence activated cell sorting. SaGA-isolated cells can then be subjected to multi-omics analysis or cellular propagation for in vitro or in vivo studies. This protocol can be applied to a variety of conditions, creating protocol flexibility for user-specific research interests. The SaGA technique can be accomplished in one workday by non-specialists and results in a phenotypically defined cellular subpopulation for integration with multi-omics techniques. We envision this approach providing multi-dimensional datasets exploring the relationship between live-cell phenotype and multi-omic heterogeneity within normal and diseased cellular populations.

Data-driven spatio-temporal modelling of glioblastoma

Mathematical oncology provides unique and invaluable insights into tumour growth on both the microscopic and macroscopic levels. This review presents state-of-the-art modelling techniques and focuses on their role in understanding glioblastoma, a malignant form of brain cancer. For each approach, we summarize the scope, drawbacks and assets. We highlight the potential clinical applications of each modelling technique and discuss the connections between the mathematical models and the molecular and imaging data used to inform them. By doing so, we aim to prime cancer researchers with current and emerging computational tools for understanding tumour progression. By providing an in-depth picture of the different modelling techniques, we also aim to assist researchers who seek to build and develop their own models and the associated inference frameworks. Our article thus strikes a unique balance. On the one hand, we provide a comprehensive overview of the available modelling techniques and their applications, including key mathematical expressions. On the other hand, the content is accessible to mathematicians and biomedical scientists alike to accommodate the interdisciplinary nature of cancer research.

The interface stiffness and topographic feature dictate interfacial invasiveness of cancer spheroids

During cancer metastasis, tumor cells likely navigate, in a collective manner, discrete tissue spaces comprising inherently heterogeneous extracellular matrix microstructures where interfaces may be frequently encountered. Studies have shown that cell migration modes can be determined by adaptation to mechanical/topographic cues from interfacial microenvironments. However, less attention has been paid to exploring the impact of interfacial mechnochemical attributes on invasive and metastatic behaviors of tumor aggregates. Here, we excogitated a collagen matrix-solid substrate interface platform to investigate the afore-stated interesting issue. Our data revealed that stiffer interfaces stimulated spheroid outgrowth by motivating detachment of single cells and boosting their motility and velocity. However, stronger interfacial adhesive strength between matrix and substrate led to the opposite outcomes. Besides, this interfacial parameter also affected the morphological switch between migration modes of the detached cells and their directionality. Mechanistically, myosin II-mediated cell contraction, compared to matrix metalloproteinases-driven collagen degradation, was shown to play a more crucial role in the invasive outgrowth of tumor spheroids in interfacial microenvironments. Thus, our findings highlight the importance of heterogeneous interfaces in addressing and combating cancer metastasis.

Identification of a ceRNA Network Driven by Copy Number Variations in Esophageal Cancer

BACKGROUND

Copy number variation (CNV) is associated with progression of esophageal cancer (EC), a common gastrointestinal neoplasm.

METHODS

Using sequencing data, CNV data, and clinical data of EC transcriptome samples obtained from public databases, we performed differential expression analysis on sequencing data. Differentially expressed CNV-driven lncRNAs were screened using the chi-square test, and CNV-driven lncRNA-associated miRNAs and mRNAs were predicted. Cytoscape software was then used to construct ceRNA networks. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to investigate biological functions of mRNAs in the ceRNA network. Survival curves were plotted to explore correlations between lncRNAs in the ceRNA network and overall survival of CNV patients. Multiple databases were used to predict lncRNAs-related drugs.

RESULTS

A dysregulated lncRNA-associated ceRNA network driven by CNV in EC, including 11 lncRNAs, 11 miRNAs and 159 mRNAs, was constructed. Downstream enrichment of mRNAs was related to biological processes such as extracellular matrix organization, indicating that these mRNAs mainly participate in intercellular exchange between tumor cells. Additionally, expression of all lncRNAs in the ceRNA network, except LINC00950, LINC01270 and MIR181A1HG, was correlated with patients' CNV. In addition, none of the 11 lncRNAs was significantly correlated with overall survival of CNV patients. CH5424802 and PD-033299CNV mainly affected the RTK signaling pathway and the cell cycle of tumor cells via RP11-180N14.1 and RP11-273 G15.2 in the ceRNA network.

CONCLUSIONS

This study identified 11 CNV-driven lncRNAs that might affect EC development, 2 of which have promising effects if applied to drug treatment. These findings might assist in identifying novel treatments for EC.

Modeling of glioma growth using modified reaction-diffusion equation on brain MR images

BACKGROUND AND OBJECTIVE

Modeling of glioma growth and evolution is of key importance for cancer diagnosis, predicting clinical progression and improving treatment outcomes of neurosurgery. However, existing models are unable to characterize spatial variations of the proliferation and infiltration of tumor cells, making it difficult to achieve accurate prediction of tumor growth.

METHODS

In this paper, a new growth model of brain tumor using a reaction-diffusion equation on brain magnetic resonance images is proposed. Both the heterogeneity of brain tissue and the density of tumor cells are used to estimate the proliferation and diffusion coefficients of brain tumor cells. The diffusion coefficient that characterizes tumor diffusion and infiltration is calculated based on the ratio of tissues (white and gray matter), while the proliferation coefficient is evaluated using the spatial gradient of tumor cells. In addition, a parameter space is constructed using inverse distance weighted interpolation to describe the spatial distribution of proliferation coefficient.

RESULTS

The glioma growth predicted by the proposed model were tested by comparing with the real magnetic resonance images of the patients. Experiments and simulation results show that the proposed method achieves accurate modeling of glioma growth. The interpolation-based growth model has higher average dice score of 0.0647 and 0.0545, and higher average Jaccard index of 0.0673 and 0.0573, respectively, compared to the uniform- and gradient-based growth models.

CONCLUSIONS

The experimental results demonstrate the feasibility of calculating the proliferation and diffusion coefficients of the growth model based on patient-specific anatomy. The parameter space that characterizes spatial distribution of proliferation and diffusion coefficients is established and incorporated into the simulation of glioma growth. It enables to obtain patient-specific models about glioma growth by estimating and calibrating only a few model parameters.

Identification of the collagen family as prognostic biomarkers in papillary thyroid carcinoma

OBJECTIVE

The aim of this study was to construct a collagen-related prognostic model for thyroid cancer and to investigate prognostic value of collagen family genes for thyroid cancer.

METHODS

A LASSO Cox regression model for thyroid cancer was developed based on the expression profiles of collagen-related genes. Kaplan-Meier survival analysis was performed for high and low risk groups. The ROC method was used to assess its predictive performance. Predictive independence was verified by multivariate Cox regression analysis. The relationship between this feature and immune cell infiltration was analyzed by tumor microenvironment. COL18A1 was validated by immunohistochemistry and RT-PCR in thyroid cancer tissues. The effect of COL18A1 on cell proliferation, migration and invasion ability of tumor cells were further valuated by CCK-8 assay and transwell assay. The effect of COL18A1 on the immune escape ability of tumor cells was further valuated by cytotoxicity assays.

RESULTS

A model including 4 collagen family genes was developed to predict thyroid cancer prognosis. Patients with high-risk score had a poorer prognosis than those with low-risk scores for 1-, 2-, 3-, and 5- year survival. The model independently predicted prognosis after adjusting for other prognostic factors. A nomogram combining risk score and age was constructed with high sensitivity and specificity. This feature was significantly associated with immune cell infiltration. COL18A1 was aberrantly over-expressed in thyroid cancer compared with control tissues and significantly increased proliferative capacity, migration capacity, invasion capacity, and immune escape ability of tumor cells.

CONCLUSION

Our findings establish a signature associated with collagen family genes that can be a promising tool to predict the prognosis of thyroid cancer. High COL18A1 expression significantly correlates with the poor prognosis of patients and enhances the immune escape ability of tumor cells.

Glioma diagnosis and therapy: Current challenges and nanomaterial-based solutions

Glioma is often referred to as one of the most dreadful central nervous system (CNS)-specific tumors with rapidly-proliferating cancerous glial cells, accounting for nearly half of the brain tumors at an annual incidence rate of 30-80 per a million population. Although glioma treatment remains a significant challenge for researchers and clinicians, the rapid development of nanomedicine provides tremendous opportunities for long-term glioma therapy. However, several obstacles impede the development of novel therapeutics, such as the very tight blood-brain barrier (BBB), undesirable hypoxia, and complex tumor microenvironment (TME). Several efforts have been dedicated to exploring various nanoformulations for improving BBB permeation and precise tumor ablation to address these challenges. Initially, this article briefly introduces glioma classification and various pathogenic factors. Further, currently available therapeutic approaches are illustrated in detail, including traditional chemotherapy, radiotherapy, and surgical practices. Then, different innovative treatment strategies, such as tumor-treating fields, gene therapy, immunotherapy, and phototherapy, are emphasized. In conclusion, we summarize the article with interesting perspectives, providing suggestions for future glioma diagnosis and therapy improvement.

A miniaturized screening platform to identify novel regulators of extracellular matrix alignment

Extracellular matrix alignment contributes to metastasis in a number of cancers and is a known prognostic stromal factor; however, the mechanisms controlling matrix organization remain unclear. Cancer-associated fibroblasts (CAF) play a critical role in this process, particularly via matrix production and modulation of key signaling pathways controlling cell adhesion and contractility. Stroma normalization, as opposed to elimination, is a highly sought strategy, and screening for drugs that effectively alter extracellular matrix (ECM) alignment is a practical way to identify novel CAF-normalizing targets that modulate ECM organization. To meet this need, we developed a novel high-throughput screening platform in which fibroblast-derived matrices were produced in 384-well plates, imaged with automated confocal microscopy, and analyzed using a customized MATLAB script. This platform is a technical advance because it miniaturizes the assay, eliminates costly and time-consuming experimental steps, and streamlines data acquisition and analysis to enable high-throughput screening applications. As a proof of concept, this platform was used to screen a kinase inhibitor library to identify modulators of matrix alignment. A number of novel potential regulators were identified, including several receptor tyrosine kinases (c-MET, tropomyosin receptor kinase 1 (NTRK1), HER2/ERBB2) and the serine/threonine kinases protein kinase A, C, and G (PKA, PKC, and PKG). The expression of these regulators was analyzed in publicly available patient datasets to examine the association between stromal gene expression and patient outcomes.

Novel synthesis of fibronectin derived photoluminescent carbon dots for bioimaging applications

Fibronectin (FN) derived from human plasma has been used for the first time as the carbon precursor in the top-down, microwave-assisted hydrothermal synthesis of nitrogen doped carbon dots (CDs). FN is a large glycoprotein primarily known for its roles in cell adhesion and cell growth. Due to these properties FN can be over expressed in the extracellular matrix (ECM) of some cancers allowing FN to be used as an indicator for the detection of cancerous cells over non-cancerous cells. These FN derived CDs display violet photoluminescence with UV excitation and appear to possess similar functional groups on their surface to their carbon precursor (-COOH and -NH2). This is believed to be due to the self-passivation of the CDs' nitrogen-containing surface functional groups during the heating process. These CDs were then used to stain MCF-7 and MDA-231 breast cancer cells and were observed to interact primarily with the cell membrane rather than intercalating into the cell like the many other types of CDs. This led to the hypothesis that the CDs are selectively binding to the FN overexpressed within the cancer cells' ECM via amide linkages. This is in agreement with the EDX and FTIR spectra of the FN CDs which indicate the presence of -COOH and nitrogen containing surface groups like -NH3. The inherent selectivity of the CDs combined with their ability to photoluminesce enables their use as a fluorophore for bioimaging applications.

Comprehensive analysis of LAMC1 expression and prognostic value in kidney renal papillary cell carcinoma and clear cell carcinoma

Background: Laminin subunit gamma 1 (LAMC1) protein is associated with tumor cell invasion and metastasis. However, its role in kidney cancer remains unclear. In this work, we sought to probe the expression as well as its carcinogenic mechanisms of LAMC1 in kidney renal papillary cell carcinoma (KIRP) and kidney renal clear cell carcinoma (KIRC).

Methods: Public databases including TIMER, Oncomine, UALCAN, TISIDB, TCGA, Kaplan–Meier plotter, UCSC Xena, cBioPortal, SurvivalMeth, KEGG, GeneMANIA, Metascape, GSCALite and GDSC were adopted, and the expression, clinical pathological correlation, prognostic signatures, dominant factors influencing LAMC1 expression, DNA methylation levels, gene mutations, copy number variations, functional networks, and drug sensitivity were analyzed. Expression of LAMC1 protein in clinical KIRP and KIRC was validated using tissue array.

Results:LAMC1 expression in KIRP and KIRC were significantly higher than those in normal tissues. High LAMC1 expression indicated poor overall survival in KIRP patients and better overall survival in KIRC patients. Through the univariate and multivariate Cox analysis, we found that high LAMC1 expression was a potential independent marker for poor prognosis in KIRP, however it implied a better prognosis in KIRC by univariate Cox analysis. In addition, the LAMC1 expression in KIRP and KIRC was negatively correlated with methylation levels of LAMC1 DNA. Interestingly, LAMC1 expression was positively correlated with the infiltration of CD8⁺ T cells, dendritic cells and neutrophils in KIRP; however, it was positively correlated with the infiltration of CD4⁺ T cells, macrophages and neutrophils but negatively correlated with B cells in KIRC. Moreover, high level of CD8⁺ T cells is beneficial for KIRC prognosis but opposite for KIRP. LAMC1 may participate in signaling pathways involved in formation of adherens junction and basement membrane in KIRP and KIRC, and the high expression of LAMC1 is resistant to most drugs or small molecules of the Genomics of Drug Sensitivity in Cancer database.

Conclusion: Enhanced LAMC1 expression suggests a poor prognosis in KIRP while a better prognosis in KIRC, and these opposite prognostic signatures of LAMC1 may be related to different immune microenvironments.

Collagen Remodeling along Cancer Progression Providing a Novel Opportunity for Cancer Diagnosis and Treatment

The extracellular matrix (ECM) is a significant factor in cancer progression. Collagens, as the main component of the ECM, are greatly remodeled alongside cancer development. More and more studies have confirmed that collagens changed from a barrier to providing assistance in cancer development. In this course, collagens cause remodeling alongside cancer progression, which in turn, promotes cancer development. The interaction between collagens and tumor cells is complex with biochemical and mechanical signals intervention through activating diverse signal pathways. As the mechanism gradually clears, it becomes a new target to find opportunities to diagnose and treat cancer. In this review, we investigated the process of collagen remodeling in cancer progression and discussed the interaction between collagens and cancer cells. Several typical effects associated with collagens were highlighted in the review, such as fibrillation in precancerous lesions, enhancing ECM stiffness, promoting angiogenesis, and guiding invasion. Then, the values of cancer diagnosis and prognosis were focused on. It is worth noting that several generated fragments in serum were reported to be able to be biomarkers for cancer diagnosis and prognosis, which is beneficial for clinic detection. At a glance, a variety of reported biomarkers were summarized. Many collagen-associated targets and drugs have been reported for cancer treatment in recent years. The new targets and related drugs were discussed in the review. The mass data were collected and classified by mechanism. Overall, the interaction of collagens and tumor cells is complicated, in which the mechanisms are not completely clear. A lot of collagen-associated biomarkers are excavated for cancer diagnosis. However, new therapeutic targets and related drugs are almost in clinical trials, with merely a few in clinical applications. So, more efforts are needed in collagens-associated studies and drug development for cancer research and treatment.

Mechanosensitive expression of the mesenchymal subtype marker connective tissue growth factor in glioblastoma

Mechanical forces created by the extracellular environment regulate biochemical signals that modulate the inter-related cellular phenotypes of morphology, proliferation, and migration. A stiff microenvironment induces glioblastoma (GBM) cells to develop prominent actin stress fibres, take on a spread morphology and adopt trapezoid shapes, when cultured in 2D, which are phenotypes characteristic of a mesenchymal cell program. The mesenchymal subtype is the most aggressive among the molecular GBM subtypes. Recurrent GBM have been reported to transition to mesenchymal. We therefore sought to test the hypothesis that stiffer microenvironments-such as those found in different brain anatomical structures and induced following treatment-contribute to the expression of markers characterising the mesenchymal subtype. We cultured primary patient-derived cell lines that reflect the three common GBM subtypes (mesenchymal, proneural and classical) on polyacrylamide (PA) hydrogels with controlled stiffnesses spanning the healthy and pathological tissue range. We then assessed the canonical mesenchymal markers Connective Tissue Growth Factor (CTGF) and yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ) expression, via immunofluorescence. Replating techniques and drug-mediated manipulation of the actin cytoskeleton were utilised to ascertain the response of the cells to differing mechanical environments. We demonstrate that CTGF is induced rapidly following adhesion to a rigid substrate and is independent of actin filament formation. Collectively, our data suggest that microenvironmental rigidity can stimulate expression of mesenchymal-associated molecules in GBM.

Reciprocity of Cell Mechanics with Extracellular Stimuli: Emerging Opportunities for Translational Medicine

Human cells encounter dynamic mechanical cues in healthy and diseased tissues, which regulate their molecular and biophysical phenotype, including intracellular mechanics as well as force generation. Recent developments in bio/nanomaterials and microfluidics permit exquisitely sensitive measurements of cell mechanics, as well as spatiotemporal control over external mechanical stimuli to regulate cell behavior. In this review, the mechanobiology of cells interacting bidirectionally with their surrounding microenvironment, and the potential relevance for translational medicine are considered. Key fundamental concepts underlying the mechanics of living cells as well as the extracelluar matrix are first introduced. Then the authors consider case studies based on 1) microfluidic measurements of nonadherent cell deformability, 2) cell migration on micro/nano-topographies, 3) traction measurements of cells in three-dimensional (3D) matrix, 4) mechanical programming of organoid morphogenesis, as well as 5) active mechanical stimuli for potential therapeutics. These examples highlight the promise of disease diagnosis using mechanical measurements, a systems-level understanding linking molecular with biophysical phenotype, as well as therapies based on mechanical perturbations. This review concludes with a critical discussion of these emerging technologies and future directions at the interface of engineering, biology, and medicine.

Nanotherapeutic treatment of the invasive glioblastoma tumor microenvironment

Glioblastoma (GBM) is the most common malignant adult brain cancer with no curative treatment strategy. A significant hurdle in GBM treatment is effective therapeutic delivery to the brain-invading tumor cells that remain following surgery within functioning brain regions. Developing therapies that can either directly target these brain-invading tumor cells or act on other cell types and molecular processes supporting tumor cell invasion and recurrence are essential steps in advancing new treatments in the clinic. This review highlights some of the drug delivery strategies and nanotherapeutic technologies that are designed to target brain-invading GBM cells or non-neoplastic, invasion-supporting cells residing within the GBM tumor microenvironment.

Sculpting Rupture-Free Nuclear Shapes in Fibrous Environments

Cytoskeleton-mediated force transmission regulates nucleus morphology. How nuclei shaping occurs in fibrous in vivo environments remains poorly understood. Here suspended nanofiber networks of precisely tunable (nm-µm) diameters are used to quantify nucleus plasticity in fibrous environments mimicking the natural extracellular matrix. Contrary to the apical cap over the nucleus in cells on 2-dimensional surfaces, the cytoskeleton of cells on fibers displays a uniform actin network caging the nucleus. The role of contractility-driven caging in sculpting nuclear shapes is investigated as cells spread on aligned single fibers, doublets, and multiple fibers of varying diameters. Cell contractility increases with fiber diameter due to increased focal adhesion clustering and density of actin stress fibers, which correlates with increased mechanosensitive transcription factor Yes-associated protein (YAP) translocation to the nucleus. Unexpectedly, large- and small-diameter fiber combinations lead to teardrop-shaped nuclei due to stress fiber anisotropy across the cell. As cells spread on fibers, diameter-dependent nuclear envelope invaginations that run the nucleus's length are formed at fiber contact sites. The sharpest invaginations enriched with heterochromatin clustering and sites of DNA repair are insufficient to trigger nucleus rupture. Overall, the authors quantitate the previously unknown sculpting and adaptability of nuclei to fibrous environments with pathophysiological implications.

Identification of prognostic genes in the pancreatic adenocarcinoma immune microenvironment by integrated bioinformatics analysis

PURPOSE

Pancreatic adenocarcinoma (PAAD) is one of the most common causes of death among solid tumors, and its pathogenesis remains to be clarified. This study aims to elucidate the value of immune/stromal-related genes in the prognosis of PAAD through comprehensive bioinformatics analysis based on the immune microenvironment and validated in Chinese pancreatic cancer patients.

METHODS

Gene expression profiles of pancreatic cancer patients were obtained from TCGA database. Differentially expressed genes (DEGs) were identified based on the ESTIMATE algorithm. Gene co-expression networks were constructed using WGCNA. In the key module, survival analysis was used to reveal the prognostic value. Subsequently, we performed functional enrichment analysis to construct a protein-protein interaction (PPI) network. The relationship between tumor immune infiltration and hub genes was analyzed by TIMER and CIBERSORT. Finally, it was validated in the GEO database and in tissues of Chinese pancreatic cancer patients.

RESULTS

In the TCGA pancreatic cancer cohort, a low immune/stromal score was associated with a good prognosis. After bioinformatic analysis, 57 genes were identified to be significantly associated with pancreatic cancer prognosis. Among them, up-regulation of four genes (COL6A3, PLAU, MMP11 and MMP14) indicated poor prognosis and was associated with multiple immune cell infiltration. IHC results showed that PLAU protein levels from Chinese pancreatic cancer tissues were significantly higher than those from adjacent non-tumor tissues and were also associated with tumor TNM stage and lymph node metastasis.

CONCLUSION

In conclusion, this study demonstrates that PLAU may serve as a new diagnostic and therapeutic target, which is highly expressed in Chinese pancreatic cancer tissues and associated with lymph node metastasis.

Drug Delivery Systems in the Development of Novel Strategies for Glioblastoma Treatment

Glioblastoma multiforme (GBM) is a grade IV glioma considered the most fatal cancer of the central nervous system (CNS), with less than a 5% survival rate after five years. The tumor heterogeneity, the high infiltrative behavior of its cells, and the blood-brain barrier (BBB) that limits the access of therapeutic drugs to the brain are the main reasons hampering the current standard treatment efficiency. Following the tumor resection, the infiltrative remaining GBM cells, which are resistant to chemotherapy and radiotherapy, can further invade the surrounding brain parenchyma. Consequently, the development of new strategies to treat parenchyma-infiltrating GBM cells, such as vaccines, nanotherapies, and tumor cells traps including drug delivery systems, is required. For example, the chemoattractant CXCL12, by binding to its CXCR4 receptor, activates signaling pathways that play a critical role in tumor progression and invasion, making it an interesting therapeutic target to properly control the direction of GBM cell migration for treatment proposes. Moreover, the interstitial fluid flow (IFF) is also implicated in increasing the GBM cell migration through the activation of the CXCL12-CXCR4 signaling pathway. However, due to its complex and variable nature, the influence of the IFF on the efficiency of drug delivery systems is not well understood yet. Therefore, this review discusses novel drug delivery strategies to overcome the GBM treatment limitations, focusing on chemokines such as CXCL12 as an innovative approach to reverse the migration of infiltrated GBM. Furthermore, recent developments regarding in vitro 3D culture systems aiming to mimic the dynamic peritumoral environment for the optimization of new drug delivery technologies are highlighted.

Actomyosin contractility requirements and reciprocal cell-tissue mechanics for cancer cell invasion through collagen-based channels

The interstitial tumor microenvironment is composed of heterogeneously organized collagen-rich porous networks as well as channel-like structures and interfaces which provide both barriers and guidance for invading cells. Tumor cells invading 3D random porous collagen networks depend upon actomyosin contractility to deform and translocate the nucleus, whereas Rho/Rho-associated kinase-dependent contractility is largely dispensable for migration in stiff capillary-like confining microtracks. To investigate whether this dichotomy of actomyosin contractility dependence also applies to physiological, deformable linear collagen environments, we developed nearly barrier-free collagen-scaffold microtracks of varying cross section using two-photon laser ablation. Both very narrow and wide tracks supported single-cell migration by either outward pushing of collagen up to four times when tracks were narrow, or cell pulling on collagen walls down to 50% of the original diameter by traction forces of up to 40 nN when tracks were wide, resulting in track widths optimized to single-cell diameter. Targeting actomyosin contractility by synthetic inhibitors increased cell elongation and nuclear shape change in narrow tracks and abolished cell-mediated deformation of both wide and narrow tracks. Accordingly, migration speeds in all channel widths reduced, with migration rates of around 45-65% of the original speed persisting. Together, the data suggest that cells engage actomyosin contraction to reciprocally adjust both own morphology and linear track width to optimal size for effective cellular locomotion.

Limitations of Nerve Fiber Density as a Prognostic Marker in Predicting Oncological Outcomes in Hepatocellular Carcinoma

It has been shown that the presence and density of nerve fibers (NFs; NFD) in the tumor microenvironment (TME) may play an important prognostic role in predicting long-term oncological outcomes in various malignancies. However, the role of NFD in the prognosis of hepatocellular carcinoma (HCC) is yet to be explored. To this end, we aimed to investigate the impact of NFs on oncological outcomes in a large European single-center cohort of HCC patients. In total, 153 HCC patients who underwent partial hepatectomy in a curative-intent setting between 2010 and 2021 at our university hospital were included in this study. Group comparisons between patients with and without NFs were conducted and the association of recurrence-free survival (RFS) and overall survival (OS) with the presence of NFs and other clinico-pathological variables were determined by univariate and multivariable Cox regression models. Patients with NFs in the TME presented with a median OS of 66 months (95% CI: 30−102) compared to 42 months (95% CI: 20−63) for patients without NFs (p = 0.804 log-rank). Further, RFS was 26 months (95% CI: 12−40) for patients with NFs compared to 18 months (95% CI: 9−27) for patients without NFs (p = 0.666 log-rank). In a subgroup analysis, patients with NFD ≤ 5 showed a median OS of 54 months (95% CI: 11−97) compared to 48 months (95% CI: 0−106) for the group of patients with NFD > 5 (p = 0.787 log-rank). Correspondingly, the RFS was 26 months (95% CI: 10−42) in patients with NFD ≤ 5 and 29 months (95% CI: 14−44) for the subcohort with NFD > 5 (p = 0.421 log-rank). Further, group comparisons showed no clinico-pathological differences between patients with NFs (n = 76) and without NFs (n = 77) and NFs were not associated with OS (p = 0.806) and RFS (p = 0.322) in our Cox regression models. In contrast to observations in various malignancies, NFs in the TME and NFD are not associated with long-term oncological outcomes in HCC patients undergoing surgery.

Molecular neuropathology of brain-invasive meningiomas

Invasion of brain tissue by meningiomas has been identified as one key factor for meningioma recurrence. The identification of meningioma tumor tissue surrounded by brain tissue in neurosurgical samples has been touted as a criterion for atypical meningioma (CNS WHO grade 2), but is only rarely seen in the absence of other high-grade features, with brain-invasive otherwise benign (BIOB) meningiomas remaining controversial. While post-surgery irradiation therapy might be initiated in brain-invasive meningiomas to prevent recurrences, specific treatment approaches targeting key molecules involved in the invasive process are not established. Here we have compiled the current knowledge about mechanisms supporting brain tissue invasion by meningiomas and summarize preclinical models studying targeted therapies with potential inhibitory effects.

The Impact of Obesity, Adipose Tissue, and Tumor Microenvironment on Macrophage Polarization and Metastasis

Tumor metastasis is a major cause of death in cancer patients. It involves not only the intrinsic alterations within tumor cells, but also crosstalk between these cells and components of the tumor microenvironment (TME). Tumorigenesis is a complex and dynamic process, involving the following three main stages: initiation, progression, and metastasis. The transition between these stages depends on the changes within the extracellular matrix (ECM), in which tumor and stromal cells reside. This matrix, under the effect of growth factors, cytokines, and adipokines, can be morphologically altered, degraded, or reorganized. Many cancers evolve to form an immunosuppressive TME locally and create a pre-metastatic niche in other tissue sites. TME and pre-metastatic niches include myofibroblasts, immuno-inflammatory cells (macrophages), adipocytes, blood, and lymphatic vascular networks. Several studies have highlighted the adipocyte-macrophage interaction as a key driver of cancer progression and dissemination. The following two main classes of macrophages are distinguished: M1 (pro-inflammatory/anti-tumor) and M2 (anti-inflammatory/pro-tumor). These cells exhibit distinct microenvironment-dependent phenotypes that can promote or inhibit metastasis. On the other hand, obesity in cancer patients has been linked to a poor prognosis. In this regard, tumor-associated adipocytes modulate TME through the secretion of inflammatory mediators, which modulate and recruit tumor-associated macrophages (TAM). Hereby, this review describes the cellular and molecular mechanisms that link inflammation, obesity, and cancer. It provides a comprehensive overview of adipocytes and macrophages in the ECM as they control cancer initiation, progression, and invasion. In addition, it addresses the mechanisms of tumor anchoring and recruitment for M1, M2, and TAM macrophages, specifically highlighting their origin, classification, polarization, and regulatory networks, as well as their roles in the regulation of angiogenesis, invasion, metastasis, and immunosuppression, specifically highlighting the role of adipocytes in this process.

Transient Agarose Spot (TAS) Assay: A New Method to Investigate Cell Migration

Fibroblasts play a central role in diseases associated with excessive deposition of extracellular matrix (ECM), including idiopathic pulmonary fibrosis. Investigation of different properties of fibroblasts, such as migration, proliferation, and collagen-rich ECM production is unavoidable both in basic research and in the development of antifibrotic drugs. In the present study we developed a cost-effective, 96-well plate-based method to examine the migration of fibroblasts, as an alternative approach to the gold standard scratch assay, which has numerous limitations. This article presents a detailed description of our transient agarose spot (TAS) assay, with instructions for its routine application. Advantages of combined use of different functional assays for fibroblast activation in drug development are also discussed by examining the effect of nintedanib—an FDA approved drug against IPF—on lung fibroblasts.

The multifaceted mechanisms of malignant glioblastoma progression and clinical implications

With the application of high throughput sequencing technologies at single-cell resolution, studies of the tumor microenvironment in glioblastoma, one of the most aggressive and invasive of all cancers, have revealed immense cellular and tissue heterogeneity. A unique extracellular scaffold system adapts to and supports progressive infiltration and migration of tumor cells, which is characterized by altered composition, effector delivery, and mechanical properties. The spatiotemporal interactions between malignant and immune cells generate an immunosuppressive microenvironment, contributing to the failure of effective anti-tumor immune attack. Among the heterogeneous tumor cell subpopulations of glioblastoma, glioma stem cells (GSCs), which exhibit tumorigenic properties and strong invasive capacity, are critical for tumor growth and are believed to contribute to therapeutic resistance and tumor recurrence. Here we discuss the role of extracellular matrix and immune cell populations, major components of the tumor ecosystem in glioblastoma, as well as signaling pathways that regulate GSC maintenance and invasion. We also highlight emerging advances in therapeutic targeting of these components.

Endocrine regulation and metabolic mechanisms of osteopontin in the development and progression of osteosarcoma, metastasis and prognosis

Osteosarcoma is the most common type of malignant bone tumor, occurring in adolescents and patients over 60. It has a bimodal onset and a poor prognosis, and its development has not yet been fully explained. Osteopontin (OPN) is a high protein consisting of 314 amino acid residues with a negative charge and is involved in many biological activities. OPN is not only an essential part of the regulation of the nervous system and endocrine metabolism of skeletal cells. Still, it is also involved in several other important biological activities, such as the division, transformation, and proliferation of skeletal cells and their associated cells, such as bone tumor cells, including bone marrow mesenchymal stem cells, hematopoietic stem cells, osteoblasts, and osteoclasts. Osteoblasts and osteocytes. Recent studies have shown a strong correlation between OPN and the development and progression of many skeletal diseases, such as osteosarcoma and rheumatoid arthritis. This review aims to understand the mechanisms and advances in the role of OPN as a factor in the development, progression, metastasis, and prognosis of osteosarcoma in an attempt to provide a comprehensive summary of the mechanisms by which OPN regulates osteosarcoma progression and in the hope of contributing to the advancement of osteosarcoma research and clinical treatment.

Sulfated Hyaluronan Modulates the Functional Properties and Matrix Effectors Expression of Breast Cancer Cells with Different Estrogen Receptor Status

Hyaluronan (HA) is an extracellular matrix glycosaminoglycan (GAG) that plays a pivotal role in breast cancer. While HA is the only GAG not normally substituted with sulfate groups, sulfated hyaluronan (sHA) has previously been used in studies with promising antitumor results. The aim of the present study was to evaluate the effects sHA fragments have on breast cancer cells with different estrogen receptor (ER) status. To this end, ERα-positive MCF-7, and ERβ-positive MDA-MB-231 cells were treated with non-sulfated HA or sHA fragments of 50 kDa. The functional properties of the breast cancer cells and the expression of key matrix effectors were investigated. According to the results, sHA attenuates cell proliferation, migration, and invasion, while increasing adhesion on collagen type I. Furthermore, sHA modulates the expression of epithelial-to-mesenchymal transition (EMT) markers, such as e-cadherin and snail2/slug. Additionally, sHA downregulates matrix remodeling enzymes such as the matrix metalloproteinases MT1-MMP, MMP2, and MMP9. Notably, sHA exhibits a stronger effect on the breast cancer cell properties compared to the non-sulfated counterpart, dependent also on the type of cancer cell type. Consequently, a deeper understanding of the mechanism by which sHA facilitate these processes could contribute to the development of novel therapeutic strategies.

Spatial heterogeneity of invading glioblastoma cells regulated by paracrine factors

Glioblastoma (GBM) is the most common and lethal type of malignant primary brain tumor in adults. GBM displays heterogeneous tumor cell population comprising glioma-initiating cells (GICs) with stem cell-like characteristics and differentiated glioma cells. During GBM cell invasion into normal brain tissues, which is the hallmark characteristic of GBM, GICs at the invasion front retain stemness, while cells at the tumor core display cellular differentiation. However, the mechanism of cellular differentiation underlying the formation of spatial cellular heterogeneity in GBM remains unknown. In the present study, we first observed spatially heterogeneous GBM cell populations emerged from an isogenic clonal population of GICs during invasion into a 3D collagen hydrogel in a microfluidic device. Specifically, GICs at the invasion front maintained stemness, while trailing cells displayed astrocytic differentiation. The spatial cellular heterogeneity resulted from the difference in cell density between GICs at the invasion front and trailing cells. Trailing GICs at high cell density exhibited astrocytic differentiation via local accumulation of paracrine factors they secreted, while cells at the invasion front of low cell density retained stemness due to the lack of paracrine factors. In addition, we demonstrated that interstitial flow suppressed astrocytic differentiation of trailing GICs by the clearance of paracrine factors. Our findings suggest that intercellular crosstalk between tumor cells is an essential factor in developing the spatial cellular heterogeneity of GBM cells with various differentiation statuses. It also provides insights into the development of novel therapeutic strategies targeting GBM cells with stem cell characteristics at the invasion front.

Sex-Based Differences in the Tumor Microenvironment

Cancers are heterogeneous multifactorial diseases consisting of a major public health issue worldwide. Sex disparities are evidenced in cancer incidence, mortality, expression of prognosis factor, response to treatment, and survival. For both sexes, an interplay of intrinsic and environmental factors influences cancer cells and tumor microenvironment (TME) components. The TME cumulates both supportive and communicative functions, contributing to cancer development, progression, and metastasis dissemination. The frontline topics of this chapter are focused on the contribution of sex, via steroid hormones, such as estrogens and androgens, on the following components of the TME: cancer-associated fibroblasts (CAFs), extracellular matrix (ECM), blood and lymphatic endothelial cells, and immunity/inflammatory system.

Spatial variation in gene expression of Tasmanian devil facial tumors despite minimal host transcriptomic response to infection

BACKGROUND

Transmissible cancers lie at the intersection of oncology and infectious disease, two traditionally divergent fields for which gene expression studies are particularly useful for identifying the molecular basis of phenotypic variation. In oncology, transcriptomics studies, which characterize the expression of thousands of genes, have identified processes leading to heterogeneity in cancer phenotypes and individual prognoses. More generally, transcriptomics studies of infectious diseases characterize interactions between host, pathogen, and environment to better predict population-level outcomes. Tasmanian devils have been impacted dramatically by a transmissible cancer (devil facial tumor disease; DFTD) that has led to widespread population declines. Despite initial predictions of extinction, populations have persisted at low levels, due in part to heterogeneity in host responses, particularly between sexes. However, the processes underlying this variation remain unknown.

RESULTS

We sequenced transcriptomes from healthy and DFTD-infected devils, as well as DFTD tumors, to characterize host responses to DFTD infection, identify differing host-tumor molecular interactions between sexes, and investigate the extent to which tumor gene expression varies among host populations. We found minimal variation in gene expression of devil lip tissues, either with respect to DFTD infection status or sex. However, 4088 genes were differentially expressed in tumors among our sampling localities. Pathways that were up- or downregulated in DFTD tumors relative to normal tissues exhibited the same patterns of expression with greater intensity in tumors from localities that experienced DFTD for longer. No mRNA sequence variants were associated with expression variation.

CONCLUSIONS

Expression variation among localities may reflect morphological differences in tumors that alter ratios of normal-to-tumor cells within biopsies. Phenotypic variation in tumors may arise from environmental variation or differences in host immune response that were undetectable in lip biopsies, potentially reflecting variation in host-tumor coevolutionary relationships among sites that differ in the time since DFTD arrival.

Hans Joachim Scherer: an under-recognized pioneer of glioma research in Belgium

Hans Joachim Scherer (1906-1946) was a German pathologist who fled Germany to Belgium to work on glioma genesis, growth and progression. Despite being seldom cited, and due to the contributions discussed in this article, Hans Joachim Scherer, can be considered a founding father of contemporary neuropathology and glioma research. We discuss Scherer's achievements in glioma classification, glomerular structures of glioma, primary and secondary glioblastoma, glioma growth patterns, non-resectability of glioma, pseudopalisadic necrosis and the late occurrence of symptoms in glioma.

Cancer cell migration in collagen-hyaluronan composite extracellular matrices

Hyaluronan (HA) is a key component in the tumor microenvironment (TME) that participates in cancer growth and invasiveness. While the molecular weight (MW) dependent properties of HA can cause tumor-promoting and -repressing effects, the elevated levels of HA in the TME impedes drug delivery. The degradation of HA using hyaluronidases (HYALs), resulting in fragments of HA, is a way to overcome this, but the consequences of changes in HA molecular weight and concentration is currently unknown. Therefore, it is critical to understand the MW-dependent biological effects of HA. Here we examine the influence of HA molecular weight on biophysical properties that regulate cell migration and extracellular matrix (ECM) remodeling. In our study, we used vLMW, LMW and HMW HA at different physiologically relevant concentrations, with a particular interest in correlating the mechanical and structural properties to different cell functions. The elastic modulus, collagen network pore size and collagen fiber diameter increased with increasing HA concentration. Although the collagen network pore size increased, these pores were filled with the bulky HA molecules. Consequently, cell migration decreased with increase in HA concentration due to multiple, long-lived and unproductive protrusions, suggesting the influence of steric factors. Surprisingly, even though elastic modulus increased with HA molecular weight and concentration, gel compaction assays showed an increased degree of ECM compaction among HMW HA gels at high concentrations (2 and 4 mg mL^-1 [0.2 and 0.4%]). These results were not seen in collagen gels that lacked HA, but had similar stiffness. HA appears to have the effect of decreasing migration and increasing collagen network contraction, but only at high HA molecular weight. Consequently, changes in HA molecular weight can have relatively large effects on cancer cell behavior. STATEMENT OF SIGNIFICANCE: Hyaluronan (HA) is a critical component of the tumor microenvironment (TME). Overproduction of HA in the TME results in poor prognosis and collapse of blood vessels, inhibiting drug delivery. Hyaluronidases have been used to enhance drug delivery. However, they lead to low molecular weight (MW) HA, altering the mechanical and structural properties of the TME and cancer cell behavior. Understanding how HA degradation affects cancer cell behavior is critical for uncovering detrimental effects of this therapy. Very little is known about how HA MW affects cancer cell behavior in tumor-mimicking collagen-HA composite networks. Here we examine how MW and HA content in collagen-HA networks alter structural and mechanical properties to regulate cell migration and matrix remodeling in 3D TME-mimicking environments.

3D two-photon polymerization of smart cell gelatin - collagen matrixes with incorporated ruthenium complexes for the monitoring of local oxygen tensions

The extra cellular matrix plays a major role in the biomechanical properties of tissues that impact cell behavior and fate. It is therefore crucial to mimic these complex cell-matrix interactions in 3D cell cultures. Here, two-photon polymerization is applied to produce gelatin methacryloyl (GelMA) - collagen matrixes that further enable local pO_2matrix measurement, when ruthenium complexes are used as photo-activators. The fluorescence intensity of these complexes has a direct and inverse relationship with the local pO_2matrix. The 3D structures reached their maximum size in cell culture conditions after 3H with a swelling factor of ~1.5. Their shape and the ruthenium fluorescence intensity of the alveoli walls stayed constant for at least 2 weeks in the absence of cells. They were used in time series to monitor the local pO_2matrix adjacent to cancer cells during their division, migration and the formation of a tumor tissue mass. At the presence of these cell activities that consume O₂, a significant ~3-fold increase of the ruthenium fluorescence intensity in the alveoli walls was observed. This study demonstrates that online monitoring of the local pO_2matrix is possible. The ruthenium complexes provide the bio-optical sensors that are useful for further analysis of cancer and healthy cell energy metabolism in a 3D matrix that better mimics in vivo conditions and migration paths. Unraveling the cancer cell metabolic adaptations in a changing micro-environment will help the development of new therapeutic opportunities. STATEMENT OF SIGNIFICANCE: In 3D cell cultures, monitoring pericellular pO₂ is as critical as controlling pH. This facility is currently missing. Here, we take advantage of the direct and inverse relationship between pO₂ and the fluorescence intensity of ruthenium complexes to generate stable gelatin-collagen matrixes able to continuously monitoring the pO₂ at the pericellular level. The ruthenium complexes, which are photo-activators in the two-photon polymerization of these matrixes, became covalently bind to the collagen fibers. Indeed, local O₂ consumption by cancer cells during migration, mitosis and tumor mass formation caused a 3-fold increase of the ruthenium fluorescence. In the future, incorporating ruthenium complexes with other bio-optical sensors will create new drug screening platforms that monitor cell culture parameters at the pericellular level.