We thank Virginie Ory, PhD for helpful discussions and advice on the approach of the 3D co-culture model. We also thank Elizabeth Jones for excellent technical assistance with the IHC sectioning. This study was supported by grants from the DFG (Deutsche Forschungsgemeinschaft) to YL (LI 2547/4-1) and the National Institutes of Health to AW (R01 CA231291), to ATR (R01 CA205632), to GWP (R01 CA218670), and the Core Grant of the Cancer Center (P30 CA51008).

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<li>Zanoni, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((3D+tumor+spheroid+models+for+In+vitro+therapeutic+screening%3A+a+systematic+approach+to+enhance+the+biological+relevance+of+data+obtained%5BTitle%5D)+AND+%22Scientific+Reports%22%5BJournal%5D)">3D tumor spheroid models for In vitro therapeutic screening: a systematic approach to enhance the biological relevance of data obtained.</a> Scientific Reports. 11 (6), 19103(2016).</li>
<li>Veelken, C., Bakker, G., Drell, D., Friedl, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Single+cell-based+automated+quantification+of+therapy+responses+of+invasive+cancer+spheroids+in+organotypic+3D+culture%5BTitle%5D)+AND+%22Methods%22%5BJournal%5D)">Single cell-based automated quantification of therapy responses of invasive cancer spheroids in organotypic 3D culture.</a> Methods. 1 (128), 139-149 (2017).</li>
<li>Puls, T. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Development+of+a+Novel+3D+Tumor-tissue+Invasion+Model+for+High-throughput%2C+High-content+Phenotypic+Drug+Screening%5BTitle%5D)+AND+%22Scientific+Reports%22%5BJournal%5D)">Development of a Novel 3D Tumor-tissue Invasion Model for High-throughput, High-content Phenotypic Drug Screening.</a> Scientific Reports. 8 (1), 13039(2018).</li>
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The authors declare that they have no competing financial interests.

The method presented here describes 3D tumor spheroid generation, which allows co-culture with T-cells, cell-based functional and molecular assays, as well as a variety of monitoring and analysis possibilities using a single device. The major advantage of our approach is that it does not necessitate transfer of the 3D culture to a separate assay and maintains the integrity of the 3D culture throughout the assays.
The workflow presented here can be modified as needed. The incubation times for s...

Despite significant improvements in cancer immunotherapy over the past decade, our mechanistic understanding of sensitivity and resistance to treatments are still fairly poor1. It is well-established that tumors display substantial heterogeneity, and that the dynamic interactions of the tumor cells with their microenvironment as well as with the immune cells, impact tumor cell death, invasive behavior and response to treatments that include immunotherapy1,2,3. As one arm of the adaptive immune system, T-cells execute cell-specific cytotoxicity. The analysis of T-cell recognition and response to cancer cells provides mechanistic insights into resistance and sensitivity to immune modulatory treatments.
In vitro modeling and monitoring interactions between cancer and T-cells in an appropriate environment has been challenging and so far, resulted in limited mechanistic insights. Most cell-based assays rely on a two-dimensional (2D) environment, that lacks key features that are critical for recapitulating the three-dimensional (3D) in vivo physiology4,5,6, namely spatial cell-cell interactions, contact with the extracellular matrix (ECM)7, dynamic metabolic demand, increased hypoxia due to mass growth8, and effects of the tumor microenvironment (TME)9. On the other hand, there are still a number of shortcomings with the currently used three-dimensional (3D) co-culture and invasion assay systems: (1) the time consuming nature of spheroid generation and harvest5,10, (2) the lack of control over spheroid size, shape and cell density11,12, (3) the low-throughput type assays, (4) the requirement for special equipment13,14, (5) the need to transfer the co-culture into distinct environments for different assays15,16,17. In particular, transferring of a co-culture assay often leads to disruption of spheroids and loss of the co-culture integrity. This applies especially for &#8220;loose&#8221; spheroids with reduced cell-cell adhesion. For example, most 3D invasion assays require that spheroids are harvested after their initial formation and then resuspended in ECM14,15,16. This resuspension step results in a loss of control over the distance between spheroids. Since distance between tumor spheroids impacts their invasive behavior, this loss of control introduces high inter-assay variance and reduces the reproducibility. Furthermore, the application of cell fractionation assays by consecutive centrifugation steps for assessment of the peripheral and tumor spheroid infiltrating immune cells is limited to tumor cell populations that generate more stable spheroids17.
Concept and approach
Our approach addresses the above-mentioned deficiencies using an &#8220;All-in-One&#8221;&#8212;3D spheroid co-culture model, which does not require the transfer of spheroids for subsequent assays. We adapted a spheroid formation device (see Table of Materials) to generate an assay for simultaneously monitoring invasive behavior of cancer cells and cytotoxicity of co-cultured T-cells. This method is user-friendly, inexpensive and allows for quick and easy handling in a relatively high-throughput 3D setting. Dependent on the type of device used, up to 81 large uniformly-sized spheroids can be generated in a single pipetting step with control over the individual spheroid size by modifying the number of cells seeded. Spheroid formation is forced by enhanced cell-cell interactions in scaffold-free agarose multi-well casts with U-shaped bottoms. We adapted this 3D system for dynamic cell-based functional studies as well as endpoint molecular and biochemical assays that include fluorescence activated cell sorting (FACS), immunofluorescence (IF) or immunohistochemistry (IHC) staining as well as gene expression analysis of the intact 3D co-culture.
For functional studies, embedding spheroids in type I collagen within the agarose casts results in invasion of cancer cells from equidistant spheroids and permits monitoring essential cell line-specific features, such as single cell vs. collective cell migration18,19. Furthermore, the collagen matrix is easily separated from the agarose cast, resulting in a 1&#8210;2 mm thick patch containing multiple spheroids, which can be further processed for IF-staining and imaging by confocal microscopy. This can reveal distinct cell invasion and cell-matrix interactions in a high-throughput screening. Also, cells in the collagen matrix can be isolated after collagen digestion and single cell dissociation for subsequent cell cultivation or analysis.
For IHC analysis of spheroids, after fixation and sectioning of the agarose cast, proteins or other molecules of interest are detectable whilst maintaining the geographic positions of the spheroids. In the approach described here, spheroids are directly embedded in Hydroxyethyl agarose processing gel within the agarose cast and the gel serves as a &#8220;lid&#8221; to retain the spheroids at the bottom of the microwells. After paraffin embedding of the agarose cast20, serial horizontal sectioning is performed with the bottom of the cast serving as the starting point.
This approach contrasts with conventional IHC sectioning of spheroids that requires harvesting of cells before embedding in Hydroxyethyl agarose processing gel21 and risks disruption of spheroids thus losing the spatial arrangement of cells. Also, cell fractionation by centrifugation for assessing whether immune cells infiltrated or remained peripheral to tumor spheroids17 is avoided by direct embedding.
Furthermore, 3D co-culture can be performed by admixing tumor, stromal or immune cells, and thus studying tumor cell crosstalk or recapitulating different tumor microenvironments for analyzing cell-cell interactions including co-cultures with endothelial cells16.
This 3D spheroid co-culture setting can be used to perform co-culture of different cell types present in the tumor microenvironment and to assess the effects of altered ECM elements. Besides type I collagen, other ECM components (e.g., matrigel, matrigel/collagen mixtures, fibronectin), can be used since tumor cell invasion is impacted by the abundance of different substrates22. Also, the microwells of the agarose cast are suitable for spheroid formation of primary cell lines and for cells with low cell-cell adhesion.

<table><tbody><tr><td>3D Petri Dishes</td><td>Microtissues Inc</td><td>Z764019 &amp;amp; Z764051</td><td>referred to as &quot;rubber molds&quot; in the protocols; 81-microwell &amp;amp; 35-microwell molds</td></tr><tr><td>8-well Chamber Slides</td><td>Lab-Tek</td><td>154534</td><td></td></tr><tr><td>Agarose Type I, low EEO</td><td>Sigma-Aldrich</td><td>A6013</td><td></td></tr><tr><td>anti-rabbit-HRP conjugated secondary antibody</td><td>Agilent</td><td>K4003</td><td>ready to use</td></tr><tr><td>Collagen Type I, Rat Tail, 100 mg</td><td>Millipore</td><td>08-115</td><td></td></tr><tr><td>Collagenase Type 4, 1 g</td><td>Worthington</td><td>LS004188</td><td></td></tr><tr><td>DMEM, fetal bovine serum</td><td>ThermoFisher</td><td>11965092, 16000044</td><td>referred to as &quot;cell culture medium&quot; in the protocols</td></tr><tr><td>Harris hematoxylin</td><td>ThermoFisher</td><td>SH30-500D</td><td></td></tr><tr><td>HistoGel</td><td>ThermoFisher</td><td>HG-4000-012</td><td>referred to as &quot;Hydroxyethyl agarose processing gel&quot; in the protocols</td></tr><tr><td>Hoechst</td><td>Life Technologies</td><td>H1399</td><td>1/1000 dilution</td></tr><tr><td>Phalloidin 546</td><td>Invitrogen</td><td>486624</td><td>1/200 dilution</td></tr><tr><td>rabbit anti-CD8 antibody</td><td>Cell Signaling</td><td>98941</td><td>1/25 dilution</td></tr><tr><td>rat anti-keratin 8</td><td>DSHB</td><td>TROMA-I AB_531826</td><td>1/500 dilution</td></tr><tr><td>RNeasy Mini Kit</td><td>Qiagen</td><td>74104</td><td>referred to as &quot;RNA extraction kit&quot; in the protocols</td></tr><tr><td>RPMI</td><td>ThermoFisher</td><td>11875093</td><td>for T-cell culture medium</td></tr><tr><td>Triton X-100</td><td>BioRad</td><td>1610407</td><td>referred to as &quot;Octoxynol&quot; in the protocols</td></tr><tr><td>Trizol</td><td>ThermoFisher</td><td>15596026</td><td>referred to as &quot;guanidinium thiocyanate with phenol&quot; in the protocols</td></tr><tr><td>Tween 20</td><td>Sigma-Aldrich</td><td>P1379</td><td>referred to as &quot;polysorbate 20&quot; in the protocols</td></tr><tr><td>TypLE</td><td>ThermoFisher</td><td>12604013</td><td>referred to as &quot;cell dissociation enzymes solution&quot; in the protocols</td></tr></tbody></table>

monitoring cancer cell invasion and t-cell cytotoxicity in 3d culture

Significant progress has been made in treating cancer with immunotherapy, although a large number of cancers remain resistant to treatment. A limited number of assays allow for direct monitoring and mechanistic insights into the interactions between tumor and immune cells, amongst which, T-cells play a significant role in executing the cytotoxic response of the adaptive immune system to cancer cells. Most assays are based on two-dimensional (2D) co-culture of cells due to the relative ease of use but with limited representation of the invasive growth phenotype, one of the hallmarks of cancer cells. Current three-dimensional (3D) co-culture systems either require special equipment or separate monitoring for invasion of co-cultured cancer cells and interacting T-cells.
Here we describe an approach to simultaneously monitor the invasive behavior in 3D of cancer cell spheroids and T-cell cytotoxicity in co-culture. Spheroid formation is driven by enhanced cell-cell interactions in scaffold-free agarose microwell casts with U-shaped bottoms. Both T-cell co-culture and cancer cell invasion into type I collagen matrix are performed within the microwells of the agarose casts without the need to transfer the cells, thus maintaining an intact 3D co-culture system throughout the assay. The collagen matrix can be separated from the agarose cast, allowing for immunofluorescence (IF) staining and for confocal imaging of cells. Also, cells can be isolated for further growth or subjected to analyses such as for gene expression or fluorescence activated cell sorting (FACS). Finally, the 3D co-culture can be analyzed by immunohistochemistry (IHC) after embedding and sectioning. Possible modifications of the assay include altered compositions of the extracellular matrix (ECM) as well as the inclusion of different stromal or immune cells with the cancer cells.

The 3D co-culture model allows for different assays shown in Figure 1A, which can be combined or modified as needed. In our established experimental setup, tumor and T-cells are co-cultured for 2 days followed by initiation of the invasion assay for selection of invasive and/or resistant tumor cells (Figure 1B). On day 4 the quantitation of invasion is performed and &#8220;survivor&#8221; cells are isolated from the collagen matrix or directly processed for RNA<...

Watch this Scientific Journal Video about Monitoring Cancer Cell Invasion and T-Cell Cytotoxicity in 3D Culture at JoVE.com

Monitoring Cancer Cell Invasion and T-Cell Cytotoxicity in 3D Culture

The presented approach simultaneously evaluates cancer cell invasion in 3D spheroid assays and T-cell cytotoxicity. Spheroids are generated in a scaffold-free agarose multi-microwell cast. Co-culture and embedding in type I collagen matrix are performed within the same device which allows to monitor cancer cell invasion and T-cell mediated cytotoxicity.

Significant progress has been made in treating cancer with immunotherapy, although a large number of cancers remain resistant to treatment. A limited ...

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Cancer Research

11.6K Views.  Georgetown University. The presented approach simultaneously evaluates cancer cell invasion in 3D spheroid assays and T-cell cytotoxicity. Spheroids are generated in a scaffold-free agarose multi-microwell cast. Co-culture and embedding in type I collagen matrix are performed within the same device which allows to monitor cancer cell invasion and T-cell mediated cytotoxicity.

Video: Monitoring Cancer Cell Invasion and T-Cell Cytotoxicity in 3D Culture

3-D Cell Culture System for Studying Invasion and Evaluating Therapeutics in Bladder Cancer

Bladder cancer is a significant health problem. It is estimated that more than 16,000 people will die this year in the United States from bladder cancer. While 75% of bladder cancers are non-invasive and unlikely to metastasize, about 25% progress to an invasive growth pattern. Up to half of the patients with invasive cancers will develop lethal metastatic relapse. Thus, understanding the mechanism of invasive progression in bladder cancer is crucial to predict patient outcomes and prevent lethal metastases. In this article, we present a three-dimensional cancer invasion model which allows incorporation of tumor cells and stromal components to mimic in vivo conditions occurring in the bladder tumor microenvironment. This model provides the opportunity to observe the invasive process in real time using time-lapse imaging, interrogate the molecular pathways involved using confocal immunofluorescent imaging and screen compounds with the potential to block invasion. While this protocol focuses on bladder cancer, it is likely that similar methods could be used to examine invasion and motility in other tumor types as well.

The processes governing bladder cancer invasion represent opportunities for biomarker and therapeutic development. Here we present a bladder cancer invasion model which incorporates 3-D culture of tumor spheroids, time-lapse imaging and confocal microscopy. This technique is useful for defining the features of the invasive process and for screening therapeutic agents.

Bladder cancer is a significant health problem. It is estimated that more than 16,000 people will die this year in the United States from bladder cancer. ...

Real-Time Detection and Capture of Invasive Cell Subpopulations from Co-Cultures

Invasion and metastatic spread of cancer cells are the major cause of death from cancer. Assays developed early on to measure the invasive potential of cancer cell populations typically generate a single endpoint measurement that does not distinguish between cancer cell subpopulations with different invasive potential. Also, the tumor microenvironment consists of different resident stromal and immune cells that alter and participate in the invasive behavior of cancer cells. Invasion into tissues also plays a role in immune cell subpopulations fending off microorganisms or eliminating diseased cells from the parenchyma and endothelial cells during tissue remodeling and angiogenesis. Real-Time Cellular Analysis (RTCA) that utilizes impedance biosensors to monitor cell invasion was a major step forward beyond endpoint measurement of invasion: this provides continuous measurements over time and thus can reveal differences in invasion rates that are lost in the endpoint assay. Using current RTCA technology, we expanded dual-chamber arrays by adding a further chamber that can contain stromal and/or immune cells and allows measuring the rate of invasion under the influence of secreted factors from co-cultured stromal or immune cells over time. Beyond this, the unique design allows for detaching chambers at any time and isolating of the most invasive cancer cell, or other cell subpopulations that are present in heterogeneous mixes of tumor isolates tested. These most invasive cancer cells and other cell subpopulations drive malignant progression to metastatic disease, and their molecular characteristics are important for in-depth mechanistic studies, the development of diagnostic probes for their detection, and the assessment of vulnerabilities. Thus, the inclusion of small- or large-molecule drugs can be used to test the potential of therapies that target cancer and/or stromal cell subpopulations with the goal of inhibiting (e.g., cancer cells) or enhancing (e.g., immune cells) invasive behavior.

We describe an approach to detect and capture invasive cell subpopulations in real-time. The experimental design uses Real-Time Cellular Analysis by monitoring changes in the electric impedance of cells. Invasive cancer, immune, endothelial or stromal cells in complex tissues can be captured, and the impact of co-cultures can be assessed.

Invasion and metastatic spread of cancer cells are the major cause of death from cancer. Assays developed early on to measure the invasive potential of ...

Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional (3D) Model

It is now well known that the cellular and tissue microenvironment are critical regulators influencing tumor initiation and progression. Moreover, the extracellular matrix (ECM) has been demonstrated to be a critical regulator of cell behavior in culture and homeostasis in vivo. The current approach of culturing cells on two-dimensional (2D), plastic surfaces results in the disturbance and loss of complex interactions between cells and their microenvironment. Through the use of three-dimensional (3D) culture assays, the conditions for cell-microenvironment interaction are established resembling the in vivo microenvironment. This article provides a detailed methodology to grow breast cancer cells in a 3D basement membrane protein matrix, exemplifying the potential of 3D culture in the assessment of cell invasion into the surrounding environment. In addition, we discuss how these 3D assays have the potential to examine the loss of signaling molecules that regulate epithelial morphology by immunostaining procedures. These studies aid to identify important mechanistic details into the processes regulating invasion, required for the spread of breast cancer.

Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional 3D Model

This article provides detailed methodologies for the use of three-dimensional (3D) assays to quantify breast cancer cell invasion. Specifically, we discuss the procedures required to set up such assays, quantification, and data analysis, as well as methods to examine the loss of membrane integrity that occurs when cells invade.

It is now well known that the cellular and tissue microenvironment are critical regulators influencing tumor initiation and progression. Moreover, the ...

Medicine

3D Models in Cancer Biology: Invasion Dynamics in Heterospheroids

Alternative Strategy to Analyze In Vitro Cell Invasion of 3D Cultures

Spheroid culture is a 3D model that provides an improved replication of the in vivo microenvironment compared to traditional two-dimensional (2D) cultures. Invasion is a cellular outcome of utmost interest in cancer biology. In this protocol, we have devised an alternative strategy for evaluating cancer cell invasion in vitro, employing heterospheroids comprised of oral squamous cell carcinoma (OSCC), cancer-associated fibroblasts (CAF), and monocytes. These heterospheroids aim to mimic the tumor microenvironment (TME), including two relevant non-neoplastic cell types alongside the cancer cells. Each cell type was labeled with vital fluorescent markers emitting in distinct wavelengths before spheroid formation. Once formed, heterospheroids were seeded onto a layer of human leiomyoma-derived extracellular matrix in the upper compartment of a microporous membrane. Invasion was assessed in the z-axis using confocal microscopy. Digital images were obtained in the corresponding fluorescent channels at 10 &#181;m intervals, covering a depth of 90 &#181;m in the z-axis. Analysis was performed using freeware image software by calculating the integrated fluorescence intensity in each image and fluorescence channel. This approach enables a more dynamic analysis of cell invasion patterns in a multilayered context, as well as the examination of spatial co-localization of different cell types during invasion.

Invasion is a major biological phenomenon in the development and progression of cancer. This process is influenced by non-neoplastic cells and components of the tumor microenvironment. The purpose of this study is to describe an alternative method for analyzing tumor cell invasion in vitro using three-dimensional (3D) cultures.

Spheroid culture is a 3D model that provides an improved replication of the in vivo microenvironment compared to traditional two-dimensional (2D) ...

Three-Dimensional (3D) Tumor Spheroid Invasion Assay

Invasion of surrounding normal tissues is generally considered to be a key hallmark of malignant (as opposed to benign) tumors. For some cancers in particular (e.g., brain tumors such as glioblastoma multiforme and squamous cell carcinoma of the head and neck &#8211; SCCHN) it is a cause of severe morbidity and can be life-threatening even in the absence of distant metastases. In addition, cancers which have relapsed following treatment unfortunately often present with a more aggressive phenotype. Therefore, there is an opportunity to target the process of invasion to provide novel therapies that could be complementary to standard anti-proliferative agents. Until now, this strategy has been hampered by the lack of robust, reproducible assays suitable for a detailed analysis of invasion and for drug screening. Here we provide a simple micro-plate method (based on uniform, self-assembling 3D tumor spheroids) which has great potential for such studies. We exemplify the assay platform using a human glioblastoma cell line and also an SCCHN model where the development of resistance against targeted epidermal growth factor receptor (EGFR) inhibitors is associated with enhanced matrix-invasive potential. We also provide two alternative methods of semi-automated quantification: one using an imaging cytometer and a second which simply requires standard microscopy and image capture with digital image analysis.

Three-Dimensional 3D Tumor Spheroid Invasion Assay

Invasion of surrounding normal tissues is a defining characteristic of malignant tumors. We provide here a simple, semi-automated micro-plate assay of invasion into a natural 3D biomatrix that has been exemplified with a number of models of advanced human cancers.

Invasion of surrounding normal tissues is generally considered to be a key hallmark of malignant (as opposed to benign) tumors. For some cancers in ...

A Cancer Cell Spheroid Assay to Assess Invasion in a 3D Setting

The invasive nature of cancer cell lines is thought to correlate with their metastatic potential. Most traditional assays, however, do not examine these invasive features in a three-dimensional environment and the resulting data suffer from reduced biological applicability. Here an approach is presented to visualize the invasive ability of cell lines in a physiologically relevant setting. The cancer cell spheroid invasion assay first utilizes gravity to generate spheroids within drops of media that hang from the lid of a cell culture dish. Next, these spheroids are embedded in a 3D matrix consisting of a mixture of basement membrane materials and type I collagen. Cancer cell egression from the spheroids into the surrounding matrix is then monitored over time. The method described here can be modified to examine invasion after coculture of different cell types, inclusion of drugs/inhibitors, or alterations in extracellular matrix (ECM) constituents.

This method evaluates cancer cell invasion from spheroids into a surrounding 3D matrix. Spheroids are generated via the hanging drop culture method and then embedded in a matrix comprised of basement membrane materials and type I collagen. Invasion out of the spheroids is subsequently monitored.

The invasive nature of cancer cell lines is thought to correlate with their metastatic potential.  Most traditional assays, however, do not examine these ...

Three-Dimensional Culture Assay to Explore Cancer Cell Invasiveness and Satellite Tumor Formation

Mammalian cell culture in monolayers is widely used to study various physiological and molecular processes. However, this approach to study growing cells often generates unwanted artifacts. Therefore, cell culture in a three-dimensional (3D) environment, often using extracellular matrix components, emerged as an interesting alternative due to its close similarity to the native in vivo tissue or organ. We developed a 3D cell culture system using two compartments, namely (i) a central compartment containing cancer cells embedded in a collagen gel acting as a pseudo-primary macrospherical tumor and (ii) a peripheral cell-free compartment made of a fibrin gel, i.e. an extracellular matrix component different from that used in the center, in which cancer cells can migrate (invasion front) and/or form microspherical tumors representing secondary or satellite tumors. The formation of satellite tumors in the peripheral compartment is remarkably correlated to the known aggressiveness or metastatic origin of the native tumor cells, which makes this 3D culture system unique. This cell culture approach might be considered to assess cancer cell invasiveness and motility, cell-extracellular matrix interactions and as a method to evaluate anti-cancer drug properties.

Cancer cells are embedded in a collagen gel and then sandwiched in an acellular fibrin gel to generate a 3D culture system in which the invasiveness and formation of satellite tumors may be monitored.

Mammalian cell culture in monolayers is widely used to study various physiological and molecular processes. However, this approach to study growing cells ...

Microfluidic Co-Culture Models for Dissecting the Immune Response in in vitro Tumor Microenvironments

Complex disease models demand cutting-edge tools able to deliver physiologically and pathologically relevant, actionable insights, and unveil otherwise invisible processes. Advanced cell assays closely mimicking in vivo scenery are establishing themselves as novel ways to visualize and measure the bidirectional tumor-host interplay influencing the progression of cancer. Here we describe two versatile protocols to recreate highly controllable 2D and 3D co-cultures in microdevices, mimicking the complexity of the tumor microenvironment (TME), under natural and therapy-induced immunosurveillance. In section 1, an experimental setting is provided to monitor crosstalk between adherent tumor cells and floating immune populations, by bright field time-lapse microscopy. As an applicative scenario, we analyze the effects of anti-cancer treatments, such as the so-called immunogenic cancer cell death inducers on the recruitment and activation of immune cells. In section 2, 3D tumor-immune microenvironments are assembled in a competitive layout. Differential immune infiltration is monitored by fluorescence snapshots up to 72 h, to evaluate combination therapeutic strategies. In both settings, image processing steps are illustrated to extract a plethora of immune cell parameters (e.g., immune cell migration and interaction, response to therapeutic agents). These simple and powerful methods can be further tailored to simulate the complexity of the TME encompassing the heterogeneity and plasticity of cancer, stromal and immune cells subtypes, as well as their reciprocal interactions as drivers of cancer evolution. The compliance of these rapidly evolving technologies with live-cell high-content imaging can lead to the generation of large informative datasets, bringing forth new challenges. Indeed, the triangle &#39;&#39;co-cultures/microscopy/advanced data analysis&#34; sets the path towards a precise problem parametrization that may assist tailor-made therapeutic protocols. We expect that future integration of cancer-immune on-a-chip with artificial intelligence for high-throughput processing will synergize a large step forward in leveraging the capabilities as predictive and preclinical tools for precision and personalized oncology.

In the age of immunotherapy and single-cell genomic profiling, cancer biology requires novel in vitro and computational tools for investigating the tumor-immune interface in a proper spatiotemporal context. We describe protocols to exploit tumor-immune microfluidic co-cultures in 2D and 3D settings, compatible with dynamic, multiparametric monitoring of cellular functions.

Complex disease models demand cutting-edge tools able to deliver physiologically and pathologically relevant, actionable insights, and unveil otherwise ...

Immunology and Infection

Tumor Cell Invasion Assay: A 3D In Vitro Native Matrix-based Method to Assess Epithelial-mesenchymal Cell Interactions

Source: Ng, Y. Z. et al. <a href="https://www.jove.com/v/51321"> Tissue Engineering of Tumor Stromal Microenvironment with Application to Cancer Cell Invasion</a>. J. Vis. Exp. (2014)
This video describes the technique of utilizing a native matrix to study tumor cell invasion. The technique used in this assay provides the ability to assess epithelial-mesenchymal cell interactions in a 3D setting without the need for a synthetic or foreign matrix.

Source: Ng, Y. Z. et al.  Tissue Engineering of Tumor Stromal Microenvironment with Application to Cancer Cell Invasion. J. Vis. Exp. (2014)
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JoVE Encyclopedia of Experiments

Skin Cancer

Assays and techniques

3D Culture Basement Membrane Assay: Culturing Cancer Cells on 3D Basement Membrane Protein Matrix to Study Cell Invasion

Source: Cvetkovi&#263;, D., et al. <a href="https://www.jove.com/v/51341/quantification-breast-cancer-cell-invasiveness-using-three">Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional (3D) Model.</a> J. Vis. Exp. (2014).
This video provides a detailed methodology to grow breast cancer cells in a 3D basement membrane protein matrix, exemplifying the potential of 3D culture in the assessment of cell invasion into the surrounding environment.

Source: Cvetkovi&#263;, D., et al. Quantification of Breast Cancer Cell Invasiveness Using a Three-dimensional (3D) Model. J. Vis. Exp. (2014).
This video ...