Biology subjects

Berens, M.

Publications and source records attributed to Berens, M..

6 recordsLinked to original sources

bioRxiv2026

A long-term organotypic slice culture model of patient high-grade glioma preserving tumor heterogeneity and architecture, and specificity of CAR T cell targeting

ABSTRACT Background: High grade glioma (HGG), encompassing IDH-wildtype glioblastoma (CNS WHO grade 4), diffuse midline glioma (CNS WHO grade 4), oligodendroglioma (IDH-mutant and 1p/19q-codeleted) CNS WHO grade 3, together with IDH-mutant astrocytoma of CNS grade 3 and grade 4, represents the most lethal group of adult diffuse gliomas. Despite significant efforts, obtaining improvements in patient survival has been limited, in part, by difficulties in comprehensive ex vivo modeling of the complexities of HGG. Although organotypic slice cultures and other platforms have shown promise, existing models often fail to capture the intrinsic cellular heterogeneity, microenvironment, and architecture of HGG, restricting investigations into their fundamental biology as well as design of novel therapeutics. Methods: We developed a patient-derived HGG organotypic slice culture (GOSC) platform demonstrating long-term preservation of intrinsic tumor characteristics. Vibratome-sectioned slices were cultured in defined medium under conditions approximating those in situ: reduced oxygen (4%), low glucose (2.5 mM), and no added growth factors. The characteristics of GOSCs after 28 days in culture, including expression of immunotherapy targets, were compared to parental tumors using histological staining, immunofluorescence, multiplexed PhenoCycler (CODEX) imaging, bulk RNA-seq expression profiling, and CAR T cell killing assays. Results: GOSCs preserved the histopathology, cell heterogeneity, tumor microenvironment, and tissue architecture of their parental tumors throughout at least 28 days in culture. Importantly, GOSCs retained parental patterns of immunotherapy target expression, and CAR T cells co-cultured with GOSCs demonstrated target-specific killing consistent with parental tumors. Conclusions: This ex vivo GOSC platform offers long-term preservation of the cellular and structural properties of parental HGG tumors, thereby providing a robust tool for extended preclinical studies, and facilitating development and evaluation of advanced tumor-targeting strategies.

cancer biology↗

bioRxiv2025

Molecular profiling of glioblastoma-derived extracellular vesicles identifies small nucleolar RNAs as candidate liquid biomarkers for radiation-induced senescence

Radiation-induced senescence (RIS) in glioblastoma (GBM) is an undesirable cell fate that reduces tumor cell death and supports resistance and outgrowth. While senescence-targeting drugs are promising adjuvants, their clinical application will require proper patient selection based on post-treatment RIS burden. Current methods to evaluate senescence, however, are tissue-based, and given GBMs difficult anatomical location, post-treatment biopsies are impractical. Innovative and less invasive biomarkers for RIS are urgently needed. To this end, we aimed to identify candidate extracellular vesicle (EV) liquid biomarkers for RIS by profiling senescence-associated cargo changes within GBM EVs. Using a panel of GBM patient-derived cell cultures, we show that RIS is the primary functional state following radiation exposure and is associated with significant alterations in the cargo of senescent-derived EVs (senEVs). In particular, senEV transcriptomes have an increased abundance of senescence-associated RNA genes and gene sets. Most striking, however, was that senEVs are most differentiated by the significant enrichment of a panel of snoRNAs. This signature was conserved in 4/5 GBM models of RIS and was validated by qRT-PCR. We further confirmed snoRNA enrichment in the senEVs of a breast cancer cell line, as well as the lack of snoRNA enrichment following senescence-independent drug exposure. Analysis by mass spectrometry revealed that snoRNAs are likely co-packaged with their associating proteins, as senEVs had concurrent increases in these binding partners. We examined whether packaging is associated with nucleolar stress during RIS, but found that upregulation in senEVs is likely due to a tightly controlled cellular abundance rather than nucleoli fragmentation and release of nucleolar components to the cytoplasm. Finally, using a preliminary cohort of longitudinal plasma samples from four GBM patients, we determined the feasibility of detecting senescence-associated and snoRNA species in the extracellular vesicles of patient biofluids. Of interest, post-treatment EVs had increased senescence-associated RNAs like CDKN2B and GLB1 and the snoRNA SNORA49. Altogether, this data suggests that senEV RNA species, and particularly snoRNAs, are a promising analyte for RIS-biomarker development. With further study, this work may open avenues for a companion diagnostic for senotherapeutics.

cancer biology↗

bioRxiv2025

Cell-Free DNA Reveals the Longitudinal Effects of Temozolomide Treatment and Host Co-Culture in Glioblastoma Models

Glioblastoma (GBM) is a highly aggressive brain tumor with limited options for longitudinal monitoring. We evaluated the potential of cell-free DNA (cfDNA) as a real-time biomarker of tumor burden under tightly controlled conditions. We measured the cfDNA release dynamics, fragmentation sizes, and variant allele frequencies (VAF) in patient-derived GBM cell cultures. Time series of cfDNA were collected and analyzed in treatment-naive monocultures, during temozolomide (TMZ) treatment, and in co-culture with normal human astrocyte (NHA) cells. Longitudinal collection of media from individual cultures demonstrated that cfDNA yield increased, indicating the ability to use cfDNA to track tumor burden over time. Using a co-culture system, we deconvoluted cfDNA admixtures by analyzing yield, fragment size patterns, and cell line-specific variants. The exclusive detection of NHA- and GBM-specific mutations confirmed the distinct contributions of each cell type. Finally, TMZ treatment of GBM cells prompted an increase in cfDNA yield and VAF, suggesting that the effects of therapy could be measured using cfDNA. These findings support cfDNA as a non-invasive biomarker for real-time monitoring of GBM progression and treatment response, with clinical potential as a liquid biopsy tool in glioblastoma management. KEY POINTSO_LIcfDNA yield and variant allele frequencies (VAFs) correlate with GBM tumor burden. C_LIO_LIcfDNA properties can be used to differentiate between cell types in a mixed population. C_LIO_LITMZ treatment increases cfDNA yield and VAFs, reflecting treatment response. C_LI IMPORTANCE OF THE STUDYThis study highlights the potential of cell-free DNA (cfDNA) as a non-invasive biomarker for monitoring glioblastoma (GBM) progression and treatment response. By utilizing in-vitro models, we demonstrate that cfDNA yield, fragmentation patterns, and variant allele frequencies (VAFs) can effectively identify treatment-induced changes, such as those induced by temozolomide (TMZ) treatment, providing insights into therapeutic response. These results have significant translational implications, as cfDNA could serve as a real-time liquid biopsy tool for monitoring GBM progression, assessing treatment efficacy, and identifying early signs of treatment resistance in clinical settings. The ability to track tumor dynamics non-invasively holds great promise for improving GBM patient management and guiding personalized therapeutic approaches.

cancer biology↗

bioRxiv2019

Probing glioblastoma and its microenvironment using single-nucleus and single-cell sequencing

Single-cell (scSeq) and single-nucleus sequencing (snSeq) are powerful tools to investigate cancer genomics at single cell resolution. Multiple studies have recently illuminated intratumoral heterogeneity in glioblastoma, however, the majority focused on molecular complexity of tumor cells, without considering unexplored host cell types that contribute to the microenvironment around tumor. To address the glioblastoma microenvironment composition and potential tumor-host interactions, we performed deep coverage sequencing of freshly resected primary GBM patient tissue without implementing any tumor enrichment strategies. The sequencing resulted in 902 cells and 1186 nuclei, respectively, passing quality control and with low mitochondrial gene percentage. We customized reference transcriptome by listing gene transcript loci as exons to take into account immature RNA, which greatly improved the alignment rate for single-nucleus data. We applied Cell Ranger pipelines (Version 3.0.2) and Seurat package (Version 2.3.1) and discovered 10 clusters in both scSeq and snSeq. Pathway analysis of each cluster signature in scSeq data along with known GBM microenvironment cell signatures revealed glioma tumor population along with surrounding microglia/macrophages, astrocytes, pericytes, oligodendrocytes, T cells and endothelial cells. The analysis of snSeq was able to capture the majority of cell types from patient tissues (tumor and microenvironment cells), but interestingly presented different cell type composition in microenvironment cell types such as microglia/macrophages. Integrating single-cell and single-nucleus transcriptomic data using canonical correlation analysis facilitated a comparison of snSeq and scSeq, contrasting depiction for certain cell types (e.g. NKX6-2 gene in Oligodendrocytes). Differential analysis of pathways between tumor and microenvironment cells unveiled potentially rewired pathways such as double strand break repair pathway. Our results demonstrate the cellular diversity of brain tumor microenvironment and lay a foundation to further investigate the individual tumor and host cell transcriptomes that are influenced not only by their cell identity but also by their interaction with surrounding microenvironment.

genomics↗

bioRxiv2019

JAM-A functions as a female microglial tumor suppressor in glioblastoma

Glioblastoma (GBM) remains refractory to treatment. In addition to its cellular and molecular heterogeneity, epidemiological studies indicate the presence of additional complexity associated with biological sex. GBM is more prevalent and aggressive in male compared to female patients, suggesting the existence of sex-specific growth, invasion, and therapeutic resistance mechanisms. While sex-specific molecular mechanisms have been reported at a tumor cell-intrinsic level, sex-specific differences in the tumor microenvironment have not been investigated. Using transgenic mouse models, we demonstrate that deficiency of junctional adhesion molecule-A (JAM-A) in female mice enhances microglia activation, GBM cell proliferation, and tumor growth. Mechanistically, JAM-A suppresses anti-inflammatory/pro-tumorigenic gene activation via interferon-activated gene 202b (Ifi202b) and found in inflammatory zone (Fizz1) in female microglia. Our findings suggest that cell adhesion mechanisms function to suppress pathogenic microglial activation in the female tumor microenvironment, which highlights an emerging role for sex differences in the GBM microenvironment and suggests that sex differences extend beyond previously reported tumor cell intrinsic differences.\n\nSummaryTuraga et al. demonstrate that female microglia drive a more aggressive glioblastoma phenotype in the context of JAM-A deficiency. These findings highlight a sex-specific role for JAM-A and represent the first evidence of sexual dimorphism in the glioblastoma microenvironment.

cancer biology↗

bioRxiv2019

Tumor cell phenotype and heterogeneity differences in IDH1 mutant vs wild-type gliomas

Glioma is recognized to be a highly heterogeneous CNS malignancy, whose diverse cellular composition and cellular interactions have not been well characterized. To gain new clinical- and biological-insights into the genetically-bifurcated IDH1 mutant (mt) vs wildtype (wt) forms of glioma, we integrated multiplexed immunofluorescence single cell data for 43 protein markers across cancer hallmarks, in addition to cell spatial metrics, genomic sequencing and magnetic resonance imaging (MRI) quantitative features. Molecular and spatial heterogeneity scores for angiogenesis and cell invasion differ between IDHmt and wt gliomas irrespective of prior treatment and tumor grade; these differences also persisted in the MR imaging features of peritumoral edema and contrast enhancement volumes. Longer overall survival for IDH1mt glioma patients may reflect generalized altered cellular, molecular, spatial heterogeneity which manifest in discernable radiological manifestations.

genomics↗