Establishment and Analysis of Tumor Slice Explants As a Prerequisite for Diagnostic Testing
November 29th, 2018
15.4K views
We provide a method for the generation, cultivation and systematic analysis of organotypic slices derived from murine lung tumors. We also describe how to optimize for slice thickness, and how to select drug concentrations to treat tumor slices.
Overview
This article presents a method for generating and analyzing organotypic slices from murine lung tumors. It details the optimization of slice thickness and drug concentration selection for effective treatment.
Key Study Components
Area of Science
- Neuroscience
- Oncology
- Preclinical Research
Background
- Organotypic slices can model complex biological functions of native tissues.
- This technique is applicable to various tissue types, including human tissues.
- Drug response studies in tumor slices can aid in diagnostics.
- Murine lung tumors serve as a model for studying tumor biology.
Purpose of Study
- To develop a systematic approach for analyzing lung tumor slices.
- To optimize conditions for drug treatment in tumor slices.
- To provide a protocol that can be adapted for different tissue types.
Methods Used
- Preparation of vibratome and tissue culture plates.
- Dissection and slicing of tumor-bearing lung tissues.
- Culture of slices in a humidified incubator.
- Drug treatment and subsequent fixation of slices for analysis.
Main Results
- Successful generation of organotypic slices from murine lung tumors.
- Optimization of slice thickness and drug concentrations demonstrated.
- Method allows for the study of drug responses in a controlled environment.
- Insights gained can be applied to other tissue types.
Conclusions
- The developed method enhances the understanding of tumor biology.
- It provides a valuable tool for preclinical drug testing.
- Future studies can expand this approach to human tissues.
Frequently Asked Questions
What are organotypic slices?
Organotypic slices are thin sections of tissue that maintain the architecture and cellular composition of the original tissue, allowing for in vitro studies.
How can this method be applied to human tissues?
The techniques described can be adapted for human tissues, enabling similar studies in human tumor biology.
What is the significance of drug response studies?
These studies can provide insights into the effectiveness of treatments and help in the development of personalized medicine approaches.
What are the advantages of using murine models?
Murine models allow for controlled experimentation and the study of disease mechanisms in a living organism.
What is the role of the vibratome in this method?
The vibratome is used to slice the tissue into thin sections while preserving the integrity of the samples for analysis.
How often should the culture medium be replenished?
The culture medium should be replenished daily to maintain optimal conditions for the tissue slices.
Executive Industry Relevance
Tumor slice explants preserve native tissue architecture and intratumor heterogeneity, enabling physiologically relevant preclinical models for diagnostic and drug response studies. This approach supports target validation by maintaining spatially resolved signaling and stromal interactions critical for mechanistic de-risking. Systematic analysis of heterogeneous markers prior to treatment ensures predictive confidence in downstream translational applications.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Interrogates therapeutic hypotheses by preserving spatially distributed oncogenic functions such as signaling activities and stromal infiltration.
- Operational Value: Enables functional target validation through analysis of marker expression heterogeneity in adjacent slices as a prerequisite for drug studies.
- Predictive Value: Supports portfolio triage by maintaining differentiation status (e.g., NKX2-1 expression) during short-term culture, reducing false-positive target assumptions.
Screening & Assay Development
- Scientific Value: Prepares validated biological systems with quantifiable outputs for downstream compound evaluation.
- Operational Value: Standardizes slice preparation and cultivation on rotating incubation units to improve viability and reproducibility across experiments.
- Scalability: Facilitates platform reuse through optimization of slice thickness (e.g., 200-micrometer) to minimize necrosis gradients and technical artifacts.
Translational & Preclinical Research
- Translational Continuity: Connects discovery through preclinical validation by enabling evaluation of drug-induced marker alterations in disease-relevant systems.
- Mechanistic De-risking: Assesses pathway-specific drug effects (e.g., mTOR via 4EBP1 phosphorylation, MAPK via ERK1/2 inhibition) in intact tissue contexts.
- Risk-Adjusted Advancement: Informs go/no-go decisions by capturing culture-induced gradients in viability, migration, or biomarker expression via layered section analysis.
Pipeline & Workflow Integration
The method integrates into the discovery continuum from early biology to lead identification by providing quantitative, spatially resolved biomarker data essential for hypothesis testing and assay readiness.
- Discovery Biology: Supports pathway clarification and biological de-risking by preserving native tissue architecture and multicellular interactions.
- Screening: Delivers assay readiness through standardized slice thickness optimization and daily medium replenishment on rotating incubation units.
- Analytics: Enables quantitative comparison of conditions via sequential section collection to capture viability and expression gradients across tissue layers.
- Translational Research: Connects to preclinical continuity by analyzing drug-treated slices for alterations in differentiation and pathway markers.
- Enterprise Reuse: Establishes a reusable capability for systematic analysis of heterogeneous tissue markers as a prerequisite across tumor types and drug classes.
Operational & Enterprise Impact
- Scientific Value: Predictive confidence through preservation of intratumor heterogeneity and stable marker expression during short-term culture.
- Operational Value: Standardization and reproducibility via rotating incubation units and optimized slice thickness (200-micrometer) to reduce necrosis and handling artifacts.
- Strategic Value: Better go/no-go decisions by enabling evaluation of targeted drug efficacy (e.g., dactolisib, selumetinib) on pathway phosphorylation in physiologically relevant models.
- Portfolio Impact: Risk-adjusted prioritization via systematic analysis of adjacent slices as zero-hour references to distinguish cultivation effects from drug responses.
Implementation Considerations
- Requires expertise in vibratome-based tissue slicing and histological processing for sequential section analysis.
- Dependent on instrumentation including rotating incubation units, microtomes, and embedding systems for FFPE sectioning.
- Necessitates cross-team standardization of slice thickness optimization and reference slice collection (top, center, bottom) to account for heterogeneity.
- Involves adaptation considerations across model systems, as thin slices (160-micrometer) may curl during handling while thick slices (250-micrometer) risk diffusion-limited necrosis.
- Practical limitation: Slice thickness must be empirically optimized per tissue type to balance viability, structural integrity, and oxygen/nutrient diffusion.
Biopharma FAQs
Why does analyzing adjacent tissue slices matter for target validation?
Analyzing adjacent slices as zero-hour references distinguishes cultivation-induced changes from drug effects, ensuring accurate interpretation of marker expression alterations in preclinical studies.
How does isolating the independent variable (slice thickness) improve discovery pipeline reliability?
Systematic optimization of slice thickness (e.g., 200-micrometer) minimizes necrosis gradients and technical artifacts, enhancing reproducibility and viability in tumor slice cultures for consistent drug response assessments.
What do quantitative dependent variable measurements (e.g., NKX2-1, phosphorylated ERK1/2) enable in target validation?
Quantitative analysis of differentiation and pathway markers confirms whether drug treatment significantly alters biological function, providing objective metrics for mechanistic de-risking and target confidence.
Why are replication requirements (e.g., top, center, bottom slices) critical for cross-functional collaboration?
Collecting reference slices from multiple tissue layers captures intratumor heterogeneity and culture-induced gradients, enabling reliable data sharing between discovery, screening, and translational teams.
What statistical analysis capabilities are required before implementing tumor slice cultures in drug response studies?
The ability to compare quantitative marker expression between cultured and uncultured slices (e.g., NKX2-1) is essential to determine whether observed changes are statistically significant and biologically meaningful.
Chapters in this video
0:04
Title
0:42
Collection of Tumor-bearing Lungs
2:08
Generation and Cultivation of Precision-cut Lung Tumor Slices, and Treatment with Inhibitors
5:58
Fixation and Processing of the Tissue Slices
7:27
Processing and Analysis of Formalin-fixed and Paraffin-embedded (FFPE) Tissues
8:33
Results: Assessment of Viability, Specific Marker Expression, and Targeted Drug Treatment on Adenocarcinoma Tissue Slices
10:26
Conclusion
