scholarly journals TAMI-48. ENGRAFTMENT PHENOTYPES IN PRECLINICAL MODEL SYSTEMS REVEAL A FUNCTIONAL SUBGROUP OF PATIENT TUMORS DEPENDENT ON THE BRAIN TUMOR MICROENVIRONMENT FOR GROWTH

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii223-ii223
Author(s):  
Nicholas Bayley ◽  
Christopher Tse ◽  
Henan Zhu ◽  
Weihong Yan ◽  
Laura Gosa ◽  
...  
Keyword(s):  
Brain Tumor ◽  
Tumor Microenvironment ◽  
Gene Expression Signature ◽  
Therapy Response ◽  
Model Systems ◽  
Preclinical Model ◽  
Expression Signature ◽  
The Brain

Abstract The derivation of model systems from patient tumors is a requisite for reproducible and high throughput translational cancer research. However, not all tumors can form a model and those that do often fail to capture the molecular diversity specific to their cancer. The potential tumor-intrinsic underpinnings remain largely unknown. In gliomas, the brain tumor microenvironment (TME) is increasingly acknowledged as a regulator of tumor proliferation, invasion, and therapy response. The dissimilar environment of in vitro and heterotopic xenograft models could potentially play a role in the limited fidelity of these model systems. Here we established a culture-free workflow and biobank of 144 glioma direct-from-patient orthotopic xenografts (DPDOX) and 51 parallel gliomasphere cultures (GS). Our direct-from-patient workflow enabled the exclusive in vivo establishment of several gliomas – hereafter termed TME-dependent tumors – including low and high grade mtIDH gliomas and histone H3.3 G34 glioblastomas notoriously difficult to culture in vitro. Through molecular profiling of over 75 patient tumors and their matched derivative models, we find that DPDOX tumors preserve a gene expression signature of neural and glial interactions not found in GS and enriched in brain TME-dependent patient tumors. While these patient tumors span a diversity of clinical diagnoses, network-based inferred transcription factor activity suggests that they converge on shared master regulators of self-renewal driving proneural and OPC/NPC-like cellular state enrichment. Integrating multi-omic profiling from TCGA and other publicly available datasets reveals that this expression signature corresponds to a shared DNA methylation signature across disparate epigenetic subgroups. These findings suggest a brain TME dependence in patient tumors across multiple molecular and clinical classifications of glioma which leads to a lack of representation in model systems failing to recapitulate tumor-promoting components of the TME. Further this work provides a resource to guide translational investigations accounting for influences of the model environment.

scholarly journals TMIC-26. PRECLINICAL MODEL SYSTEMS OF GLIOBLASTOMA REVEAL MICROENVIRONMENTAL PROGRAMS AND DEPENDENCIES IN PATIENT TUMORS

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi253-vi253
Author(s):  
Nicholas Bayley ◽  
Christopher Tse ◽  
Lynn Baufeld ◽  
Laura Gosa ◽  
Weihong Yan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Functional Divergence ◽  
Critical Role ◽  
Gene Expression Signature ◽  
Model Systems ◽  
Preclinical Model ◽  
Preclinical Models ◽  
Molecular Features ◽  
The Brain

Abstract Patient-derived model systems serve as a platform for translational research representing the heterogeneity of human cancers, and their success in recapitulating disease-driving genomic alterations is well-documented. While recent studies have demonstrated genomic and functional divergence in patient-derived models with passaging, the need for accurate preclinical models remains. Glioblastoma (GBM) is the most common and aggressive primary brain tumor, and thus far preclinical models have failed to consistently replicate the responses found in patients. We therefore aimed to evaluate the multi-omic fidelity of low-passage GBM model systems across in vitro and in vivo environments and to elucidate the molecular features in which they differ. To this end we established a biobank of glioma direct-from-patient orthotopic xenograft (GliomaPDOX) models and primary gliomasphere cultures (GSCs) and performed whole-exome and RNA sequencing of over 40 purified patient tumors and their matched GliomaPDOXs and GSCs to facilitate paired comparisons across a gradient of full tumor microenvironment (TME) presence. We observed global genomic and transcriptomic fidelity in both systems, but specific programmatic gene expression differences associated with cell-cell interactions in the brain TME, glial cell identity, and in vitro GSC-forming ability. GSCs and GSC-forming ability are strongly associated with an astrocytic gene expression signature, while more stem-like and oligodendrocytic patient tumors including IDH- and H3F3A-mutant GBMs more successfully engraft in GliomaPDOXs. This result implicates the brain TME as a support system for these more stem/oligo-like tumors. Transcription factor network analysis identified regulators of the NOTCH and MYC pathways as strongly enriched in this subgroup of patient tumors and their derivative xenografts, and provides potential targets for therapeutic intervention in near future experiments. Collectively, these findings underline the critical role of the TME in defining GBM cell state, reveal the heterogeneity of TME dependence across patient tumors, and link this dependency to therapeutically actionable molecular features.

scholarly journals Advances in Modeling the Immune Microenvironment of Colorectal Cancer

2021 ◽  
Vol 11 ◽  
Author(s):  
Paul Sukwoo Yoon ◽  
Nuala Del Piccolo ◽  
Venktesh S. Shirure ◽  
Yushuan Peng ◽  
Amanda Kirane ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Tumor Microenvironment ◽  
Immune Cells ◽  
3D Culture ◽  
Model Systems ◽  
Preclinical Model ◽  
Advantages And Disadvantages ◽  
Culture Models

Colorectal cancer (CRC) is the third most common cancer and second leading cause of cancer-related death in the US. CRC frequently metastasizes to the liver and these patients have a particularly poor prognosis. The infiltration of immune cells into CRC tumors and liver metastases accurately predicts disease progression and patient survival. Despite the evident influence of immune cells in the CRC tumor microenvironment (TME), efforts to identify immunotherapies for CRC patients have been limited. Here, we argue that preclinical model systems that recapitulate key features of the tumor microenvironment—including tumor, stromal, and immune cells; the extracellular matrix; and the vasculature—are crucial for studies of immunity in the CRC TME and the utility of immunotherapies for CRC patients. We briefly review the discoveries, advantages, and disadvantages of current in vitro and in vivo model systems, including 2D cell culture models, 3D culture systems, murine models, and organ-on-a-chip technologies.

Novel Phospholipid-Based Labrasol Nanomicelles Loaded Flavonoids for Oral Delivery with Enhanced Penetration and Anti-Brain Tumor Efficiency

2020 ◽  
Vol 17 (3) ◽  
pp. 229-245
Author(s):  
Gang Wang ◽  
Junjie Wang ◽  
Rui Guan
Keyword(s):  
Drug Delivery ◽  
Brain Tumor ◽  
Oral Delivery ◽  
Safe Delivery ◽  
Drug Delivery Vehicles ◽  
Therapeutic Benefits ◽  
Delivery Vehicles ◽  
The Brain

Background: Owing to the rich anticancer properties of flavonoids, there is a need for their incorporation into drug delivery vehicles like nanomicelles for safe delivery of the drug into the brain tumor microenvironment. Objective: This study, therefore, aimed to prepare the phospholipid-based Labrasol/Pluronic F68 modified nano micelles loaded with flavonoids (Nano-flavonoids) for the delivery of the drug to the target brain tumor. Methods: Myricetin, quercetin and fisetin were selected as the initial drugs to evaluate the biodistribution and acute toxicity of the drug delivery vehicles in rats with implanted C6 glioma tumors after oral administration, while the uptake, retention, release in human intestinal Caco-2 cells and the effect on the brain endothelial barrier were investigated in Human Brain Microvascular Endothelial Cells (HBMECs). Results: The results demonstrated that nano-flavonoids loaded with myricetin showed more evenly distributed targeting tissues and enhanced anti-tumor efficiency in vivo without significant cytotoxicity to Caco-2 cells and alteration in the Trans Epithelial Electric Resistance (TEER). There was no pathological evidence of renal, hepatic or other organs dysfunction after the administration of nanoflavonoids, which showed no significant influence on cytotoxicity to Caco-2 cells. Conclusion: In conclusion, Labrasol/F68-NMs loaded with MYR and quercetin could enhance antiglioma effect in vitro and in vivo, which may be better tools for medical therapy, while the pharmacokinetics and pharmacodynamics of nano-flavonoids may ensure optimal therapeutic benefits.

TMOD-31. AN ORGANOTYPIC TISSUE PLATFORM TO BRIDGE IN VITRO AND IN VIVO ASSAYS FOR BRAIN CANCER TREATMENT

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi222-vi222
Author(s):  
Breanna Mann ◽  
Noah Bell ◽  
Denise Dunn ◽  
Scott Floyd ◽  
Shawn Hingtgen ◽  
...  
Keyword(s):  
Cell Lines ◽  
Brain Cancer ◽  
Brain Slice ◽  
Brain Slices ◽  
In Vitro Assays ◽  
Preclinical Model ◽  
Short Period ◽  
The Brain

Abstract Brain cancers remain one of the greatest medical challenges. The lack of experimentally tractable models that recapitulate brain structure/function represents a major impediment. Platforms that enable functional testing in high-fidelity models are urgently needed to accelerate the identification and translation of therapies to improve outcomes for patients suffering from brain cancer. In vitro assays are often too simple and artificial while in vivo studies can be time-intensive and complicated. Our live, organotypic brain slice platform can be used to seed and grow brain cancer cell lines, allowing us to bridge the existing gap in models. These tumors can rapidly establish within the brain slice microenvironment, and morphologic features of the tumor can be seen within a short period of time. The growth, migration, and treatment dynamics of tumors seen on the slices recapitulate what is observed in vivo yet is missed by in vitro models. Additionally, the brain slice platform allows for the dual seeding of different cell lines to simulate characteristics of heterogeneous tumors. Furthermore, live brain slices with embedded tumor can be generated from tumor-bearing mice. This method allows us to quantify tumor burden more effectively and allows for treatment and retreatment of the slices to understand treatment response and resistance that may occur in vivo. This brain slice platform lays the groundwork for a new clinically relevant preclinical model which provides physiologically relevant answers in a short amount of time leading to an acceleration of therapeutic translation.

scholarly journals Diet, Obesity, and Cancer Progression: Are Adipocytes the Link?

2013 ◽  
Vol 6 ◽  
pp. LPI.S10871 ◽  
Author(s):  
Paul Toren ◽  
Benjamin C. Mora ◽  
Vasundara Venkateswaran
Keyword(s):  
Tumor Microenvironment ◽  
Cancer Progression ◽  
Tumor Biology ◽  
Model Systems ◽  
In Vivo Model ◽  
Diet Induced Obesity ◽  
Breast And Prostate Cancer ◽  
Obesity And Cancer

Obesity has been linked to more aggressive characteristics of several cancers, including breast and prostate cancer. Adipose tissue appears to contribute to paracrine interactions in the tumor microenvironment. In particular, cancer-associated adipocytes interact reciprocally with cancer cells and influence cancer progression. Adipokines secreted from adipocytes likely form a key component of the paracrine signaling in the tumor microenvironment. In vitro coculture models allow for the assessment of specific adipokines in this interaction. Furthermore, micronutrients and macronutrients present in the diet may alter the secretion of adipokines from adipocytes. The effect of dietary fat and specific fatty acids on cancer progression in several in vivo model systems and cancer types is reviewed. The more common approaches of caloric restriction or diet-induced obesity in animal models establish that such dietary changes modulate tumor biology. This review seeks to explore available evidence regarding how diet may modulate tumor characteristics through changes in the role of adipocytes in the tumor microenvironment.

scholarly journals Targeted Brain Tumor Therapy by Inhibiting the MDM2 Oncogene: In Vitro and In Vivo Antitumor Activity and Mechanism of Action

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1592
Author(s):  
Surendra R. Punganuru ◽  
Viswanath Arutla ◽  
Wei Zhao ◽  
Mehrdad Rajaei ◽  
Hemantkumar Deokar ◽  
...  
Keyword(s):  
Brain Tumor ◽  
Antitumor Activity ◽  
Cell Lines ◽  
Tumor Therapy ◽  
Single Agent ◽  
M Cell ◽  
In Vivo Antitumor Activity ◽  
The Brain

There is a desperate need for novel and efficacious chemotherapeutic strategies for human brain cancers. There are abundant molecular alterations along the p53 and MDM2 pathways in human glioma, which play critical roles in drug resistance. The present study was designed to evaluate the in vitro and in vivo antitumor activity of a novel brain-penetrating small molecule MDM2 degrader, termed SP-141. In a panel of nine human glioblastoma and medulloblastoma cell lines, SP-141, as a single agent, potently killed the brain tumor-derived cell lines with IC50 values ranging from 35.8 to 688.8 nM. Treatment with SP-141 resulted in diminished MDM2 and increased p53 and p21cip1 levels, G2/M cell cycle arrest, and marked apoptosis. In intracranial xenograft models of U87MG glioblastoma (wt p53) and DAOY medulloblastoma (mutant p53) expressing luciferase, treatment with SP-141 caused a significant 4- to 9-fold decrease in tumor growth in the absence of discernible toxicity. Further, combination treatment with a low dose of SP-141 (IC20) and temozolomide, a standard anti-glioma drug, led to synergistic cell killing (1.3- to 31-fold) in glioma cell lines, suggesting a novel means for overcoming temozolomide resistance. Considering that SP-141 can be taken up by the brain without the need for any special delivery, our results suggest that SP-141 should be further explored for the treatment of tumors of the central nervous system, regardless of the p53 status of the tumor.

scholarly journals Comprehensive genomic profiling of glioblastoma tumors, BTICs, and xenografts reveals stability and adaptation to growth environments

2019 ◽  
Vol 116 (38) ◽  
pp. 19098-19108 ◽  
Author(s):  
Yaoqing Shen ◽  
Cameron J. Grisdale ◽  
Sumaiya A. Islam ◽  
Pinaki Bose ◽  
Jake Lever ◽  
...  
Keyword(s):  
Brain Tumor ◽  
Massively Parallel Sequencing ◽  
Treatment Options ◽  
Culture Conditions ◽  
Model Systems ◽  
Sample Type ◽  
Tumor Initiating Cells ◽  
Growth Environment

Glioblastoma multiforme (GBM) is the most deadly brain tumor, and currently lacks effective treatment options. Brain tumor-initiating cells (BTICs) and orthotopic xenografts are widely used in investigating GBM biology and new therapies for this aggressive disease. However, the genomic characteristics and molecular resemblance of these models to GBM tumors remain undetermined. We used massively parallel sequencing technology to decode the genomes and transcriptomes of BTICs and xenografts and their matched tumors in order to delineate the potential impacts of the distinct growth environments. Using data generated from whole-genome sequencing of 201 samples and RNA sequencing of 118 samples, we show that BTICs and xenografts resemble their parental tumor at the genomic level but differ at the mRNA expression and epigenomic levels, likely due to the different growth environment for each sample type. These findings suggest that a comprehensive genomic understanding of in vitro and in vivo GBM model systems is crucial for interpreting data from drug screens, and can help control for biases introduced by cell-culture conditions and the microenvironment in mouse models. We also found that lack of MGMT expression in pretreated GBM is linked to hypermutation, which in turn contributes to increased genomic heterogeneity and requires new strategies for GBM treatment.

scholarly journals Drug Penetration into the Central Nervous System: Pharmacokinetic Concepts and In Vitro Model Systems

Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1542
Author(s):  
Felix Neumaier ◽  
Boris D. Zlatopolskiy ◽  
Bernd Neumaier
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Model Systems ◽  
Pharmacokinetic Parameters ◽  
Special Focus ◽  
Drug Penetration ◽  
The Central Nervous System ◽  
The Brain

Delivery of most drugs into the central nervous system (CNS) is restricted by the blood–brain barrier (BBB), which remains a significant bottleneck for development of novel CNS-targeted therapeutics or molecular tracers for neuroimaging. Consistent failure to reliably predict drug efficiency based on single measures for the rate or extent of brain penetration has led to the emergence of a more holistic framework that integrates data from various in vivo, in situ and in vitro assays to obtain a comprehensive description of drug delivery to and distribution within the brain. Coupled with ongoing development of suitable in vitro BBB models, this integrated approach promises to reduce the incidence of costly late-stage failures in CNS drug development, and could help to overcome some of the technical, economic and ethical issues associated with in vivo studies in animal models. Here, we provide an overview of BBB structure and function in vivo, and a summary of the pharmacokinetic parameters that can be used to determine and predict the rate and extent of drug penetration into the brain. We also review different in vitro models with regard to their inherent shortcomings and potential usefulness for development of fast-acting drugs or neurotracers labeled with short-lived radionuclides. In this regard, a special focus has been set on those systems that are sufficiently well established to be used in laboratories without significant bioengineering expertise.

CSIG-19. DISRUPTION OF DNA DAMAGE RESPONSE MODULATES THE EFFICACY OF LOCAL IMMUNOTHERAPIES IN EXPERIMENTAL GLIOMA

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi37-vi37
Author(s):  
Marilin Koch ◽  
Mykola Zdioruk ◽  
Michal Nowicki ◽  
Katharina Schregel ◽  
E Antonio Chiocca ◽  
...  
Keyword(s):  
Dna Damage ◽  
Tumor Microenvironment ◽  
Dna Damage Response ◽  
Therapy Response ◽  
Suicide Gene ◽  
Therapeutic Benefit ◽  
Damage Response

Abstract RATIONALE Herpes virus thymidine kinase (HSV-TK) suicide gene therapy is a well-established approach for in situ tumor cell killing after administration of ganciclovir (GCV), due to the induction of lethal DNA damage in HSV-TK expressing cells. Here we investigated the effects of HSV-TK gene delivery with a non-replicating serotype 5 adenovirus (AdTK) in murine glioblastoma models in combination with the ATR-inhibitor AZD6738 to disrupt the DNA damage response (DDR). METHODS We investigated the effects of disrupted DDR signaling on AdTK therapy in vitro using cytotoxicity, cytokine and flow cytometry assays in glioblastoma cell lines and in vivo with an orthotopic syngeneic murine glioblastoma model. Therapy response was monitored with MRI. Changes in the tumor microenvironment were analyzed with CyTOF. RESULTS The combination of AZD6738 with AdTK was synergistic in cytotoxicity assays, which was complemented by a significant increase of γH2AX foci. Complex modulations of the tumor microenvironment were observed with significantly reduced expression of PD-L1, MICA/B and the pro-tumorigenic cytokines IL1b and IL-4. In vivo, the combination with AZD6738 led to an increase in long-term surviving animals (66.7%) compared to GMCI (50%) and proved to be highly significant in contrast to untreated controls (p=0.0022). However, the combination treatment did not block the growth of tumors upon rechallenge in long-term survivors. CONCLUSION DDR signaling is crucial in the therapeutic efficacy of AdTK/GCV. It significantly enhances cytotoxicity in vitro and in vivo while having complex ramifications at the immunological level, requiring further studies to determine ideal conditions for a maximized therapeutic benefit.

A Model System for Proliferation and Characterisation of Stem Cells in Childhood T-ALL.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1370-1370
Author(s):  
Charlotte V. Cox ◽  
Roger S. Evely ◽  
Allison Blair
Keyword(s):  
Myeloid Cell ◽  
Scid Mice ◽  
Model Systems ◽  
Preclinical Model ◽  
Post Inoculation ◽  
Number Of Children ◽  
Cell Engraftment

Abstract T cell acute lymphoblastic leukaemias (T-ALL) are highly aggressive malignancies representing 10–15% of paediatric and 25% adult ALLs. T-ALL was considered to arise as a consequence of clonal expansion of early thymocytes. However, progress towards increasing our understanding of the biology of this disease has been hampered by lack of appropriate culture systems to study primary cells and use of murine model systems that often do not accurately reflect human disease. Traditional xenograft models of leukaemia have involved implantation of malignant cells or immortalised leukaemic cell lines with either intraperitoneal or subcutaneous localisation of leukaemia. These models do not mimic the normal pathophysiology of the disease and may therefore provide misleading data. Since evaluation of new agents in paediatric malignancies is limited by the small number of children eligible for clinical trails, there is a need for a predictive preclinical model of paediatric ALL. We have previously used a long-term suspension culture system to evaluate proliferation of T-ALL cells in vitro and demonstrated these cells had a CD34+/CD4−, CD7− phenotype. T-ALL cells with this phenotype were also capable of engrafting NOD/SCID mice, suggesting the disease may arise in a more primitive cell. In this study we have attempted to further characterise T-ALL cells with long-term proliferative ability in vivo and to investigate the kinetics of engraftment. Unsorted cells and cells sorted for the expression of CD133 and CD7 from 5 T-ALL patients were inoculated into sublethally irradiated NOD/SCID mice. Peripheral blood samples were taken at weekly intervals from the lateral tail vein from two weeks post inoculation onwards. BM samples were analysed from 4 weeks post inoculation and all animals were sacrificed no later than 10 weeks post inoculation. Human CD45+ cells were first detected at day 17-post inoculation (1.54–3.8% CD45+). By week 4, this had increased to 4.4–21% CD45+ in PB samples, while levels in BM aspirates were significantly higher at this stage (24–47% CD45+). This pattern of tissue dissemination closely mimics that observed in the patients. The levels of CD45+ cells continued to rise with time and had exceeded 85% in the BM of animals injected with cells from 3 patients by week 7-post inoculation. FISH and flow cytometric analyses showed the engrafted cells had a similar karyotype and phenotype to the patient at diagnosis and there was no evidence of myeloid cell engraftment. Cells harvested from these animals have been used in secondary, tertiary and quaternary transplants with no loss of NOD/SCID repopulating potential and similar engraftment kinetics. Quinary transplants are currently underway. In the sorted cell populations, only the CD133+/CD7− subfraction was capable of engrafting, 0.5–54% CD45+, with as few as 1.4x103–5x103 cells. There was no engraftment with the other subfractions despite injecting 10 to 1000-fold more cells. These engrafted cells expressed high levels of CD34, CD2, CD4 and CD7 and very low levels of CD133. This phenotype was similar to that of the patients at diagnosis, implying they had differentiated in vivo. These data add to the evidence that T-ALL may arise in a cell with a more primitive phenotype, rather than committed thymocytes. These cells may be the most relevant targets for emerging therapeutic strategies and we describe a robust, reproducible in vivo leukaemia model which could be used to investigate the efficacy of novel agents for the treatment of paediatric T-ALL.

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