This work is supported by the bequest of Moshe Shimon and Judith Weisbrodt.

1. HMCA Plate Embossing
NOTE: The complete process for the design and fabrication of polydimethylsiloxane (PDMS) stamp and HMCA imaging plate used in this protocol is described in detail in our previous articles15,16. The PDMS stamp (negative shape) is used to emboss the HMCA (positive shape) which consists of approximately 450 MCs per well (Figure 1A). As demonstrated in Figure 1B, each of the MCs has a shape of a truncated upside-down square-shaped pyramid (height: 190 &#181;m, small base area: 90 &#181;m x 90 &#181;m,&#160;and large base area:&#160;370 &#181;m x 370 &#181;m). The HMCA plate is used for the preparation and culturing of 3D tumor spheroids and thereafter, for invasion assay. Alternatively, a commercial stamp could be used for HMCA production.
<ol>
	<li>Prepare a solution of 6% low melting agarose (LMA). Insert the LMA powder and sterile phosphate buffered saline (PBS) (0.6 g of LMA per 10 mL of PBS) into a glass bottle with a magnetic stirrer. Place the bottle on a heating plate and stir the solution while heating to 80 &#176;C for a few hours until a uniform solution is achieved. Keep the solution at 70 &#176;C until use.</li>
	<li>Pre-heat the PDMS stamp to 70 &#176;C in the oven. Keep it warm until use. Alternatively, use a commercial stamp and follow the instruction.</li>
	<li>Place the commercial 6-well glass-bottom plates on a dry bath pre-heated to 75 &#176;C. Wait a few minutes until the plate is totally warm.</li>
	<li>Pour a drop (400 &#181;L) of pre-heated LMA onto the glass bottom of each one of the wells in the plate. Gently place the pre-heated PDMS stamp over the agarose drop. Incubate at room temperature (RT) for 5&#8211;10 min for pre-gelling and pre-cooling. Incubate at 4 &#176;C for 20 min to achieve full agarose gelation. Then, gently peel off the PDMS, leaving the agarose gel patterned with MCs. 
	NOTE: This step is done simultaneously in all the wells.</li>
	<li>Place the embossed plate in a light curing system equipped with ultraviolet (UV) lamp, and incubate for 3 min. 
	NOTE: Now the HMCA plate is UV sterilized.</li>
	<li>Fill the macro-wells with sterile PBS to ensure that they are kept humid, then cover the plate, wrap it with parafilm and store it at 4 &#176;C until use.</li>
	<li>Before use, empty PBS residuals from the HMCA plate. Place it in the biological hood.</li>
</ol>
2. Loading Cells and Spheroid Formation
<ol>
	<li>Collect the cells as follows: remove all medium from a 10 cm culture plate cell monolayer, wash twice with 10 mL of PBS to dispose of serum residuals, add 5 mL of trypsin (pre-warmed to 37 &#176;C) and incubate for 3 min in the incubator at 37 &#176;C. Then, shake the plate gently to ensure monolayer detachment, add 10 mL of complete medium (pre-warmed to 37 &#176;C) and pipette up and down until homogenous cell suspension is achieved. Centrifuge and wash the cell suspension with 15 mL of fresh medium, then, suspend at appropriate concentrations in fresh complete medium.</li>
	<li>Gently load the cell suspension (50 &#181;L, 150&#8211;360 x 103 cells/mL in medium, ~16&#8211;40 cells per MC) on top of the HMCA and allow the cells to settle by gravity for 15 min.</li>
	<li>Gently add 6&#8211;8 aliquots of 500 &#181;L fresh medium (total 3&#8211;4 mL) to the rim of the macro-well plastic bottom outside the ring and hydrogel array.</li>
	<li>Incubate HeLa cells for 72 h and MCF7 cells for 48 h at 37 &#176;C and 5% CO2, in a humidified atmosphere for the formation of spheroids.</li>
</ol>
3. Viability Detection by Propidium Iodide (PI) Staining
<ol>
	<li>Prepare a stock solution of PI (500 &#181;g of PI per 1 mL of PBS). Keep it at 4 &#176;C for about 6 months. Freshly prepare a dilution of 1:2,000 (0.25 &#181;g/mL), by the addition of 6 &#181;L of stock to 12 mL of complete medium without phenol red, for the 6-well HMCA plate (2 mL per well).</li>
	<li>Transfer the HMCA plate with 48-72 h spheroids, from the incubator to the biological hood. Remove all medium from the HMCA by leaning the tip end on the edge of the macro-well plastic bottom beside the hydrogel array, leaving the array tank filled with medium.</li>
	<li>Gently add 2 mL of PI dilution from Step 3.1 to each well, by leaning the tip end on the edge of the macro-well plastic bottom. Incubate the HMCA plate for 1 h at 37 &#176;C and 5% CO2, in a humidified atmosphere. Continue to Step 7. 
	NOTE: Other dyes could be used here as well, for example, Hoechst for nucleus staining, tetramethylrhodamine methyl ester (TMRM) for mitochondrial membrane potential staining, fluorescein diacetate (FDA) for live cells detection, Annexin V for apoptosis detection and others.</li>
</ol>
4. Collagen Mixture Preparation
<ol>
	<li>Prepare sterile double distilled water (DDW) by autoclave and a stock of 100 mL of 1 M NaOH filter-sterilized solution. Maintain the materials at RT, and the tips used for collagen mixture preparation frozen at -20 &#176;C, until use.</li>
	<li>10&#8211;20 min before use, place all intergrades including: sterile DDW, 1 M NaOH sterile solution, sterile 10x PBS, type I collagen from rat tail (stored at 4 &#176;C for 3&#8211; months) and a sterile tube into the ice bucket until totally cooled. Place the ice bucket inside the biological hood.</li>
	<li>Prepare 1,800 &#181;L of collagen mixture at a final concentration of 3 mg/mL, for 6-well HMCA invasion assay plate (300 &#181;L per well) as follows. Add the intergrades into the cooled tube in the following order: 515 &#181;L of DDW, 24.8 &#181;L of 1 M NaOH and 180 &#181;L of 10x PBS. Mix well by vortex and place back into the ice. Finally, add 1080 &#181;L of collagen to the mixture, vortex again and put back into ice.</li>
</ol>
5. HA and Collagen Mixture Preparation
<ol>
	<li>Dissolve 10 mg of HA in 2 mL of sterile DDW. Incubate the mixture at RT for a few minutes and vortex gently until the powder is totally dissolved. Store the stock solution at 4 &#176;C for up to two years.</li>
	<li>Right before use, place the HA stock solution in the ice bucket inside the biological hood.</li>
	<li>Prepare a 3 mg/mL collagen mixture as described in Step 4. Add 36 &#181;g (7.2 &#181;L) of HA into 1,800 &#956;L of ready to use collagen mixture, for a final concentration of 20 &#181;g/mL. Then, vortex again briefly and put back into ice.</li>
</ol>
6. ECM Mixture Addition
<ol>
	<li>Transfer the HMCA plate, with 48&#8211;72 h spheroids, from the incubator into the biological hood and place it on the ice. Incubate for 10 min until the plate is cooled. Pre-heat a solution of 1% LMA to 37 &#176;C in a water bath.</li>
	<li>Remove all medium from around the HMCA, by leaning the tip end on the edge of the macro-well plastic bottom beside the hydrogel array. Then, very carefully, remove all medium from the array tank with a fine tip/gel loading tip, by leaning the tip end on the array edge, gently and slowly sucking all medium out. 
	NOTE: After removing all medium from around the hydrogel array, the array tank is still filled with medium. This medium has to be removed very gently in order to avoid destruction of the hydrogel MC and dislocation of spheroids.</li>
	<li>Take 150 &#181;L of the collagen mixture or HA and collagen mixture (ECM mixture) with the pre-frozen fine tip and add into the array tank by attaching the tip to the array edge. Release the mixture slowly to avoid spheroid dislocation. Repeat this step with another aliquot of 150 &#181;L, for a total 300 &#181;L per well. Follow the same procedure for each well until all wells are filled. Then place the plate into the incubator for 1 h for the full gelation of the ECM.</li>
	<li>After the full gelation of ECM has been achieved, pipette 400 &#181;L of pre-warmed 1% LMA on top of the ECM gel. Cover the plate with its lid, incubate the plate at RT for 5&#8211;7 min and then for 2 min at 4 &#176;C, for agarose gelation. Finally, gently add 2 mL of complete medium by leaning the tip end on the edge of the macro-well plastic bottom. 
	NOTE: The agarose layer prevents the detachment of the collagen-gel matrix from the HMCA.</li>
</ol>
7. Invasion Assay Acquisition and Analysis
<ol>
	<li>Load the HMCA plate onto a motorized inverted microscope stage equipped with an incubator, pre-adjusted to 37 &#176;C, 5% CO2 and humidified atmosphere.</li>
	<li>Pre-determine the positions for image acquisition in each well so as to cover the whole array area, and use 10X or 4X objectives (this step is required for the image acquisition software used here, see the Materials Table below for details). Alternatively, use any image acquisition software to facilitate automatic scan of the entire required area, by choosing the&#160;&#34;Stich&#34; option.</li>
	<li>Acquire bright field (BF) images every 2&#8211;4 h for a total period of 24&#8211;72 h in order to follow the invasion of cells from the spheroid body into the surrounding ECM.</li>
	<li>Acquire fluorescent images for PI detection by using a dedicated fluorescent cube (excitation filter 530&#8211;550 nm, dichroic mirror 565 nm long pass and emission filter 600&#8211;660 nm).</li>
	<li>Export time-lapse BF/fluorescent images from the image acquisition software and save them in tagged image file format (TIFF) to a dedicated folder by using the &#34;Database&#34; tab in the toolbar and then the &#34;Export record files&#34; button. 
	NOTE: We developed a special in-house analysis code in MATLAB software that includes a designed graphic user interface (GUI) in which invasion analysis could be executed faster and easier. In this analysis code, the segmentation of the spheroids and invasion area is done semi-automatically using Sobel filter followed by the morphological operators Erosion and Dilation. After automatic segmentation of the areas, manual corrections were made where needed for better accuracy. After the segmentation completion, a set of parameters were automatically calculated by the software and exported to an excel file for further manipulation. The list of parameters are: basic spheroid sectional area at time = 0, invasion area of cells connected to spheroid body = main invasion area, area of cells separated from main invasion area, number of cells separated from main invasion area, average distance of invasion from the basic spheroid center of mass to the circumference of the main invasion area and separated cells and collective invasion distance parameter = d (d = &#8730; ((X2 - X1)2 + (Y2 - Y1)2) out of the X and Y spheroid center of mass coordinates, before (X1, Y1) and after (X2, Y2) collective invasion process). Alternatively, image analysis could be done with any other specialized software.</li>
	<li>Open the GUI and push the &#34;Load BF&#34; button. After the image is open, adjust the segmentation parameters (minimum size: &#62;1 and radius close: &#62;1) to achieve a precise segmentation of spheroid and its invasion area, then, press &#34;Region of interest (ROI) segmentation&#34; button for execution and a border will appear around each spheroid. If the automatic segmentation is incorrect, press the &#34;Delete&#34;&#160;or&#160;&#34;Add&#34; button and make the requested corrections manually. Repeat the same steps for subsequent images.</li>
	<li>Press the&#160;&#34;Tracking&#34; button to number the spheroids and the software will assign the same number for each spheroid in each of the time lapse images. Then, press the &#34;Measurement&#34; button, which will generate a spreadsheet with all parameters. Save this spreadsheet as an excel file for further use in results processing and statistics in excel software.</li>
</ol>

<ol>
	<li>Guan, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+metastases:+challenges+and+opportunities.">Cancer metastases: challenges and opportunities.</a> Acta pharmaceutica Sinica. B. 5 (5), 402-418 (2015).</li><li>Sapudom, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+phenotype+of+cancer+cell+invasion+controlled+by+fibril+diameter+and+pore+size+of+3D+collagen+networks.">The phenotype of cancer cell invasion controlled by fibril diameter and pore size of 3D collagen networks.</a> Biomaterials. 52, 367-375 (2015).</li><li>Portillo-Lara, R., Annabi, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microengineered+cancer-on-a-chip+platforms+to+study+the+metastatic+microenvironment.">Microengineered cancer-on-a-chip platforms to study the metastatic microenvironment.</a> Lab on a chip. 16 (21), 4063-4081 (2016).</li><li>Gkountela, S., Aceto, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stem-like+features+of+cancer+cells+on+their+way+to+metastasis.">Stem-like features of cancer cells on their way to metastasis.</a> Biology Direct. 11 (1), 33 (2016).</li><li>Kramer, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+cell+migration+and+invasion+assays.">In vitro cell migration and invasion assays.</a> Mutation Research/Reviews in Mutation Research. 752 (1), 10-24 (2013).</li><li>Guzman, A., S&#225;nchez Alemany, V., Nguyen, Y., Zhang, C. R., Kaufman, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+3D+in+vitro+metastasis+model+elucidates+differential+invasive+strategies+during+and+after+breaching+basement+membrane.">A novel 3D in vitro metastasis model elucidates differential invasive strategies during and after breaching basement membrane.</a> Biomaterials. 115, 19-29 (2017).</li><li>Lee, E., Song, H. -. H. G., Chen, C. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomimetic+on-a-chip+platforms+for+studying+cancer+metastasis.">Biomimetic on-a-chip platforms for studying cancer metastasis.</a> Current opinion in chemical engineering. 11, 20-27 (2016).</li><li>Mittler, F., Obe&#239;d, P., Rulina, A. V., Haguet, V., Gidrol, X., Balakirev, M. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-Content+Monitoring+of+Drug+Effects+in+a+3D+Spheroid+Model.">High-Content Monitoring of Drug Effects in a 3D Spheroid Model.</a> Frontiers in Oncology. 7, 293 (2017).</li><li>Evensen, N. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+High-Throughput+Three-Dimensional+Invasion+Assay+for+Anti-Cancer+Drug+Discovery.">Development of a High-Throughput Three-Dimensional Invasion Assay for Anti-Cancer Drug Discovery.</a> PLoS ONE. 8 (12), e82811 (2013).</li><li>Aw Yong, K. M., Li, Z., Merajver, S. D., Fu, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tracking+the+tumor+invasion+front+using+long-term+fluidic+tumoroid+culture.">Tracking the tumor invasion front using long-term fluidic tumoroid culture.</a> Scientific Reports. 7 (1), 10784 (2017).</li><li>Mi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic+co-culture+system+for+cancer+migratory+analysis+and+anti-metastatic+drugs+screening.">Microfluidic co-culture system for cancer migratory analysis and anti-metastatic drugs screening.</a> Scientific Reports. 6 (1), 35544 (2016).</li><li>Chung, S., Sudo, R., Mack, P. J., Wan, C. -. R., Vickerman, V., Kamm, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+migration+into+scaffolds+under+co-culture+conditions+in+a+microfluidic+platform.">Cell migration into scaffolds under co-culture conditions in a microfluidic platform.</a> Lab on a chip. 9 (2), 269-275 (2009).</li><li>Krakhmal, N. V., Zavyalova, M. V., Denisov, E. V., Vtorushin, S. V., Perelmuter, V. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+Invasion:+Patterns+and+Mechanisms.">Cancer Invasion: Patterns and Mechanisms.</a> Acta naturae. 7 (2), 17-28 (2015).</li><li>Lintz, M., Mu&#241;oz, A., Reinhart-King, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Mechanics+of+Single+Cell+and+Collective+Migration+of+Tumor+Cells.">The Mechanics of Single Cell and Collective Migration of Tumor Cells.</a> Journal of Biomechanical Engineering. 139 (2), 21005 (2017).</li><li>Afrimzon, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogel+microstructure+live-cell+array+for+multiplexed+analyses+of+cancer+stem+cells,+tumor+heterogeneity+and+differential+drug+response+at+single-element+resolution.">Hydrogel microstructure live-cell array for multiplexed analyses of cancer stem cells, tumor heterogeneity and differential drug response at single-element resolution.</a> Lab on a Chip. 16 (6), 1047-1062 (2016).</li><li>Shafran, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nitric+oxide+is+cytoprotective+to+breast+cancer+spheroids+vulnerable+to+estrogen-induced+apoptosis.">Nitric oxide is cytoprotective to breast cancer spheroids vulnerable to estrogen-induced apoptosis.</a> Oncotarget. 8 (65), 108890-108911 (2017).</li><li>Sato, H., Idiris, A., Miwa, T., Kumagai, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfabric+Vessels+for+Embryoid+Body+Formation+and+Rapid+Differentiation+of+Pluripotent+Stem+Cells.">Microfabric Vessels for Embryoid Body Formation and Rapid Differentiation of Pluripotent Stem Cells.</a> Scientific Reports. 6 (1), 31063 (2016).</li><li>Lee, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gravity-oriented+microfluidic+device+for+uniform+and+massive+cell+spheroid+formation.">Gravity-oriented microfluidic device for uniform and massive cell spheroid formation.</a> Biomicrofluidics. 6 (1), 14114 (2012).</li><li>Zaretsky, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+the+dynamics+of+primary+T+cell+activation+and+differentiation+using+long+term+live+cell+imaging+in+microwell+arrays.">Monitoring the dynamics of primary T cell activation and differentiation using long term live cell imaging in microwell arrays.</a> Lab on a Chip. 12 (23), 5007 (2012).</li><li>Khan, N., Syed, D. N., Ahmad, N., Mukhtar, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fisetin:+a+dietary+antioxidant+for+health+promotion.">Fisetin: a dietary antioxidant for health promotion.</a> Antioxidants &amp; redox signaling. 19 (2), 151-162 (2013).</li><li>Lee, G. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Networked+concave+microwell+arrays+for+constructing+3D+cell+spheroids.">Networked concave microwell arrays for constructing 3D cell spheroids.</a> Biofabrication. 10 (1), 15001 (2017).</li><li>Vinci, M., Box, C., Eccles, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+(3D)+tumor+spheroid+invasion+assay.">Three-dimensional (3D) tumor spheroid invasion assay.</a> Journal of visualized experiments: JoVE. (99), e52686 (2015).</li><li>Toh, Y. -. C., Raja, A., Yu, H., van Noort, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+3D+Microfluidic+Model+to+Recapitulate+Cancer+Cell+Migration+and+Invasion.">A 3D Microfluidic Model to Recapitulate Cancer Cell Migration and Invasion.</a> Bioengineering. 5 (2), 29 (2018).</li><li>Sugimoto, M., Kitagawa, Y., Yamada, M., Yajima, Y., Utoh, R., Seki, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Micropassage-embedding+composite+hydrogel+fibers+enable+quantitative+evaluation+of+cancer+cell+invasion+under+3D+coculture+conditions.">Micropassage-embedding composite hydrogel fibers enable quantitative evaluation of cancer cell invasion under 3D coculture conditions.</a> Lab on a Chip. 18 (9), 1378-1387 (2018).</li><li>Yamamoto, S., Hotta, M. M., Okochi, M., Honda, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+Vascular+Formed+Endothelial+Cell+Network+on+the+Invasive+Capacity+of+Melanoma+Using+the+In+Vitro+3D+Co-Culture+Patterning+Model.">Effect of Vascular Formed Endothelial Cell Network on the Invasive Capacity of Melanoma Using the In Vitro 3D Co-Culture Patterning Model.</a> PLoS ONE. 9 (7), e103502 (2014).</li><li>Lee, S. -. H., Moon, J. J., West, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+micropatterning+of+bioactive+hydrogels+via+two-photon+laser+scanning+photolithography+for+guided+3D+cell+migration.">Three-dimensional micropatterning of bioactive hydrogels via two-photon laser scanning photolithography for guided 3D cell migration.</a> Biomaterials. 29 (20), 2962-2968 (2008).</li><li>Gschwind, A., Zwick, E., Prenzel, N., Leserer, M., Ullrich, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+communication+networks:+epidermal+growth+factor+receptor+transactivation+as+the+paradigm+for+interreceptor+signal+transmission.">Cell communication networks: epidermal growth factor receptor transactivation as the paradigm for interreceptor signal transmission.</a> Oncogene. 20 (13), 1594-1600 (2001).</li><li>Jiang, K., Dong, C., Xu, Y., Wang, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic-based+biomimetic+models+for+life+science+research.">Microfluidic-based biomimetic models for life science research.</a> RSC Advances. 6 (32), 26863-26873 (2016).</li><li>Mason, B. N., Starchenko, A., Williams, R. M., Bonassar, L. J., Reinhart-King, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tuning+three-dimensional+collagen+matrix+stiffness+independently+of+collagen+concentration+modulates+endothelial+cell+behavior.">Tuning three-dimensional collagen matrix stiffness independently of collagen concentration modulates endothelial cell behavior.</a> Acta biomaterialia. 9 (1), 4635-4644 (2013).</li><li>Raub, C. B., Putnam, A. J., Tromberg, B. J., George, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Predicting+bulk+mechanical+properties+of+cellularized+collagen+gels+using+multiphoton+microscopy.">Predicting bulk mechanical properties of cellularized collagen gels using multiphoton microscopy.</a> Acta Biomaterialia. 6 (12), 4657-4665 (2010).</li><li>Paszek, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tensional+homeostasis+and+the+malignant+phenotype.">Tensional homeostasis and the malignant phenotype.</a> Cancer Cell. 8 (3), 241-254 (2005).</li><li>Rao, S. S., DeJesus, J., Short, A. R., Otero, J. J., Sarkar, A., Winter, J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glioblastoma+Behaviors+in+Three-Dimensional+Collagen-Hyaluronan+Composite+Hydrogels.">Glioblastoma Behaviors in Three-Dimensional Collagen-Hyaluronan Composite Hydrogels.</a> ACS Applied Materials &amp; Interfaces. 5 (19), 9276-9284 (2013).</li><li>Kreger, S. T., Voytik-Harbin, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyaluronan+concentration+within+a+3D+collagen+matrix+modulates+matrix+viscoelasticity,+but+not+fibroblast+response.">Hyaluronan concentration within a 3D collagen matrix modulates matrix viscoelasticity, but not fibroblast response.</a> Matrix Biology. 28 (6), 336-346 (2009).</li><li>Chanmee, T., Ontong, P., Itano, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hyaluronan:+A+modulator+of+the+tumor+microenvironment.">Hyaluronan: A modulator of the tumor microenvironment.</a> Cancer Letters. 375 (1), 20-30 (2016).</li><li>Zhao, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulating+Three-Dimensional+Microenvironment+with+Hyaluronan+of+Different+Molecular+Weights+Alters+Breast+Cancer+Cell+Invasion+Behavior.">Modulating Three-Dimensional Microenvironment with Hyaluronan of Different Molecular Weights Alters Breast Cancer Cell Invasion Behavior.</a> ACS Applied Materials &amp; Interfaces. 9 (11), 9327-9338 (2017).</li><li>Wu, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+role+of+low+molecular+weight+hyaluronan+in+breast+cancer+metastasis.">A novel role of low molecular weight hyaluronan in breast cancer metastasis.</a> The FASEB Journal. 29 (4), 1290-1298 (2015).</li><li>Fisher, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+resistance,+high+molecular+weight+hyaluronic+acid,+and+longevity.">Cancer resistance, high molecular weight hyaluronic acid, and longevity.</a> Journal of cell communication and signaling. 9 (1), 91-92 (2015).</li></ol>

The authors declare that they have no competing financial interests.

It is well documented that living organisms, characterized by their complex 3D multicellular organization are quite distinct from the commonly used 2D monolayer cultured cells, emphasizing the crucial need to use cellular models which better mimic the functions and processes of the living organism for drug screening. Recently, multicellular spheroids, organotypic cultures, organoids and organs-on-a-chip have been introduced8 for the use in standardized drug discovery. However, the 3D multicellular...

Cancer death is attributed mainly to the dissemination of metastatic cells to distant locations. Many efforts in cancer treatment focus on targeting or preventing the formation of metastatic colonies and progression of systemic metastatic disease1. Cancer cell migration is a crucial step in the tumor metastasis process, thus, the research of the cancer invasion cascade is very important and a prerequisite to finding anti-metastatic therapeutics.
The use of animal models as tools for studying metastatic disease has been found to be very expensive and not always representative of the tumor in humans. Moreover, the extracellular microenvironment topology, mechanics and composition strongly affect cancer cell behavior2. Since in vivo models inherently lack the ability to separate and control such specific parameters which contribute to cancer invasion and metastasis, there is a need for controllable biomimetic in vitro models.
In order to metastasize to distant organs, cancer cells must exhibit migratory and invasive phenotypic traits which can be targeted for therapy. However, since most in vitro cancer models do not mimic the actual features of solid tumors3, it is very challenging to detect physiologically relevant phenotypes. In addition, the phenotypic heterogeneity that exists within the tumor, dictates the need for analyzing tumor migration at single-element resolution in order to discover phenotype-directed therapies, for instance, by targeting the metastasis-initiating cell population within heterogeneous tumors4.
The study of cell motility and collective migration is primarily conducted in monolayer cultures of epithelial cells on homogeneous planar surfaces. These conventional cellular models for cancer cell migration are based on the population analysis of individual cells invading through the membranes and ECM components5, but in such systems, the intrinsic differences between individual cells cannot be studied. Generating 3D spheroids either via scaffolds or in scaffold-free micro-structures is considered as a superior means to study the tumor cell growth and cancer invasion6,7,8. However, most 3D systems are not suitable to high throughput formats, and inter-spheroid interaction cannot usually be achieved since isolated individual spheroids are generated in each micro-well9. Recent studies involving the cancer migration are based on microfluidic devices3,10,11,12, however, these sophisticated microfluidic tools are difficult to produce and cannot be used for high throughput screening (HTS) of anti-invasive drugs.
Two main phenotypes, collective and individual cell migration, which play a role in tumor cells overcoming the ECM barrier and invading neighboring tissue, have been demonstrated13,14, each displaying distinct morphological characteristics, biochemical, molecular and genetic mechanisms. In addition, two forms of migrating tumor cells, fibroblast-like and amoeboid, are observed in each phenotype. Since both, invasion phenotypes and migration modes, are mainly defined by morphological properties, there is a need for cellular models that enable imaging-based detection and examination of all forms of tumor invasion and migrating cells.
The overall goal of the current method is to provide a simple and reproducible biomimetic 3D in vitro cell-based system for the analysis of invasion capacity in large populations of tumor spheroids. Here, we introduce the HMCA-based 6-well imaging plate for the research of tumor invasion and anti-metastatic therapy. The technology enables the formation of large numbers of uniform 3D tumor spheroids (450 per well) in a hydrogel micro-chambers (MC) structure. Various ECM components are added to the spheroid array to enable the invasion of the cells into the surrounding environment. Invasion process is continuously monitored by short- and long-term observation of the same individual spheroids/invading cells and facilitates morphological characterization, fluorescent staining and retrieval of specific spheroids at any point. Since numerous spheroids share space and medium, interaction via soluble molecules between individual spheroids and their impact on one another is possible. Semi-automatic image analysis is performed by using in-house MATLAB code which enables faster and more efficient collection of large amount of data. The platform facilitates accurate, simultaneous measurement of numerous spheroids/invading cells in a time-efficient manner, allowing medium throughput screening of anti-invasion drugs.

<table>
	<tbody>
		<tr>
			<td>6 Micro-well Glass Bottom Plates with 14 mm micro-well #1.5 cover glass</td>
			<td>Cellvis</td>
			<td>P06-14-1.5-N</td>
			<td>Commercial glass bottom plates which are used for HMCA embossing</td>
		</tr>
		<tr>
			<td>UltraPure Low Melting Point Agarose</td>
			<td>Invitrogen</td>
			<td>16520100</td>
			<td>A solution of 6% agarose is warmed up to 80&#176;C before use, a solution of 1% agarose is warmed to 37&#176;C</td>
		</tr>
		<tr>
			<td>Trypsin EDTA solution B</td>
			<td>Biological Industries</td>
			<td>03-052-1A</td>
			<td>Warmed to 37&#176;C before use</td>
		</tr>
		<tr>
			<td>DMEM medium, high glucose</td>
			<td>Biological Industries</td>
			<td>01-055-1A</td>
			<td>Warmed to 37&#176;C before use</td>
		</tr>
		<tr>
			<td>Special Newborn Calf Serum (NBCS)</td>
			<td>Biological Industries</td>
			<td>04-122-1A</td>
			<td>Heat Inactivated</td>
		</tr>
		<tr>
			<td>DPBS (10X), no calcium, no magnesium</td>
			<td>Biological Industries</td>
			<td>02-023-5A</td>
			<td>Kept on ice before use</td>
		</tr>
		<tr>
			<td>NaOH, anhydrous</td>
			<td>Sigma-Aldrich</td>
			<td>S5881-500G</td>
			<td>Used for the preparation of 1M NaOH solution</td>
		</tr>
		<tr>
			<td>Cultrex Type I collagen from rat tail, 5mg/ml</td>
			<td>Trevigen</td>
			<td>3440-100-01</td>
			<td>Kept on ice before use</td>
		</tr>
		<tr>
			<td>Hyaluronic acid sodium salt</td>
			<td>Sigma-Aldrich</td>
			<td>H5542-10MG</td>
			<td>Kept on ice before use</td>
		</tr>
		<tr>
			<td>Fisetin</td>
			<td>Sigma-Aldrich</td>
			<td>F505-100MG</td>
			<td>Added to the culture medium, invasion inhibitor</td>
		</tr>
		<tr>
			<td>DETA/NO</td>
			<td>Enzo Life Sciences</td>
			<td>alx-430-014-m005</td>
			<td>Added to the culture medium, nitric oxide donor</td>
		</tr>
		<tr>
			<td>PI</td>
			<td>Sigma-Aldrich</td>
			<td>P4170</td>
			<td>Used at very low concenrtation without the need for washing</td>
		</tr>
		<tr>
			<td>Dymax 5000-EC UV flood lamp complete system with light shield &#38; Dymax 400 Watt EC power supply</td>
			<td>Dymax Corporation</td>
			<td>PN 39823</td>
			<td>Used for HMCA plate sterilization by UV</td>
		</tr>
		<tr>
			<td>Inverted IX81 microscope</td>
			<td>Olympus</td>
			<td></td>
			<td>Used for automatic image acquisition</td>
		</tr>
		<tr>
			<td>Incubator for microscope</td>
			<td>Life Imaging Services</td>
			<td></td>
			<td>Essential for time lapse experiments with image acquisition, pre adjusted to 37&#176;C, 5% CO2 and keeping a humidified atmosphere</td>
		</tr>
		<tr>
			<td>Sub-micron motorized stage type SCAN-IM</td>
			<td>Marzhauser Wetzlar GmbH</td>
			<td></td>
			<td>Used to predetermine image acquisition areas, for automatic image acquisition</td>
		</tr>
		<tr>
			<td>14-bit, ORCA II C4742-98 cooled camera</td>
			<td>Hamamatsu Photonics</td>
			<td></td>
			<td>Highly sensitive, used for imaging</td>
		</tr>
		<tr>
			<td>Fluorescent filter cube for PI detection</td>
			<td>Chroma Technology Corporation</td>
			<td></td>
			<td>Filter cube specifications: excitation filter 530-550 nm, dichroic mirror 565 nm long pass and emission filter 600-660 nm</td>
		</tr>
		<tr>
			<td>The Olympus Cell^P operating software</td>
			<td>Olympus</td>
			<td></td>
			<td>Software used to control microscope, motorized stage, camera and image acquisition</td>
		</tr>
		<tr>
			<td>Matlab R2014B analysis software</td>
			<td>Mathworks</td>
			<td></td>
			<td>Used to develop in house graphic user interface for image analysis</td>
		</tr>
		<tr>
			<td>Excel software</td>
			<td>Microsoft</td>
			<td></td>
			<td>Used for data management, calculation, plot creation and statistics</td>
		</tr>
	</tbody>
</table>

analysis of cancer cell invasion and anti-metastatic drug screening using hydrogel micro-chamber array (hmca)-based plates

Cancer metastasis is known to cause 90% of cancer lethality. Metastasis is a multistage process which initiates with the penetration/invasion of tumor cells into neighboring tissue. Thus, invasion is a crucial step in metastasis, making the invasion process research and development of anti-metastatic drugs, highly significant. To address this demand, there is a need to develop 3D in vitro models which imitate the architecture of solid tumors and their microenvironment most closely to in vivo state on one hand, but at the same time be reproducible, robust and suitable for high yield and high content measurements. Currently, most invasion assays lean on sophisticated microfluidic technologies which are adequate for research but not for high volume drug screening. Other assays using plate-based devices with isolated individual spheroids in each well are material consuming and have low sample size per condition. The goal of the current protocol is to provide a simple and reproducible biomimetic 3D cell-based system for the analysis of invasion capacity in large populations of tumor spheroids. We developed a 3D model for invasion assay based on HMCA imaging plate for the research of tumor invasion and anti-metastatic drug discovery. This device enables the production of numerous uniform spheroids per well (high sample size per condition) surrounded by ECM components, while continuously and simultaneously observing and measuring the spheroids at single-element resolution for medium throughput screening of anti-metastatic drugs. This platform is presented here by the production of HeLa and MCF7 spheroids for exemplifying single cell and collective invasion. We compare the influence of the ECM component hyaluronic acid (HA) on the invasive capacity of collagen surrounding HeLa spheroids. Finally, we introduce Fisetin (invasion inhibitor) to HeLa spheroids and nitric oxide (NO) (invasion activator) to MCF7 spheroids. The results are analyzed by in-house software which enables semi-automatic, simple and fast analysis which facilitates multi-parameter examination.

The unique HMCA imaging plate is used for the invasion assay of 3D tumor spheroids. The entire assay, beginning with the spheroid formation and ending with the invasion process and additional manipulations, is performed within the same plate. For the spheroid formation, HeLa cells are loaded into the array basin and settle in the hydrogel MCs by gravity. The hydrogel MCs, which have non-adherent/low attachment characteristics, facilitate the cell-cell interaction and the formation of 3D t...

Watch this Scientific Journal Video about Analysis of Cancer Cell Invasion and Anti-metastatic Drug Screening Using Hydrogel Micro-chamber Array HMCA-based Plates at JoVE.com

Analysis of Cancer Cell Invasion and Anti-metastatic Drug Screening Using Hydrogel Micro-chamber Array HMCA-based Plates

A HMCA-based imaging plate is presented for invasion assay performance. This plate facilitates the formation of three-dimensional (3D) tumor spheroids and the measurement of cancer cell invasion into the extracellular matrix (ECM). The invasion assay quantification is achieved by semi-automatic analysis.

Analysis of Cancer Cell Invasion and Anti-metastatic Drug Screening Using Hydrogel Micro-chamber Array (HMCA)-based Plates

Cancer metastasis is known to cause 90% of cancer lethality. Metastasis is a multistage process which initiates with the penetration/invasion of tumor ...

analysis-cancer-cell-invasion-anti-metastatic-drug-screening-using

Research

JoVE Journal

Cancer Research

9.0K Views.  Bar-Ilan University. A HMCA-based imaging plate is presented for invasion assay performance. This plate facilitates the formation of three-dimensional (3D) tumor spheroids and the measurement of cancer cell invasion into the extracellular matrix (ECM). The invasion assay quantification is achieved by semi-automatic analysis.

Video: Analysis of Cancer Cell Invasion and Anti-metastatic Drug Screening Using Hydrogel Micro-chamber Array HMCA-based Plates

Utilizing Functional Genomics Screening to Identify Potentially Novel Drug Targets in Cancer Cell Spheroid Cultures

The identification of functional driver events in cancer is central to furthering our understanding of cancer biology and indispensable for the discovery of the next generation of novel drug targets. It is becoming apparent that more complex models of cancer are required to fully appreciate the contributing factors that drive tumorigenesis in vivo and increase the efficacy of novel therapies that make the transition from pre-clinical models to clinical trials.
Here we present a methodology for generating uniform and reproducible tumor spheroids that can be subjected to siRNA functional screening. These spheroids display many characteristics that are found in solid tumors that are not present in traditional two-dimension culture. We show that several commonly used breast cancer cell lines are amenable to this protocol. Furthermore, we provide proof-of-principle data utilizing the breast cancer cell line BT474, confirming their dependency on amplification of the epidermal growth factor receptor HER2 and mutation of phosphatidylinositol-4,5-biphosphate 3-kinase (PIK3CA) when grown as tumor spheroids. Finally, we are able to further investigate and confirm the spatial impact of these dependencies using immunohistochemistry.

Identifying novel drug targets that transition from pre-clinical testing to human trials is a scientific priority. To that end, here we describe a functional genomics approach for examining the impact of gene depletion on cancer cell line spheroids, which more appropriately model human cancers in vivo.

The identification of functional driver events in cancer is central to furthering our understanding of cancer biology and indispensable for the discovery ...

A Model for Perineural Invasion in Head and Neck Squamous Cell Carcinoma

Perineural invasion (PNI) is found in approximately 40% of head and neck squamous cell carcinomas (HNSCC). Despite multimodal treatment with surgery, radiation, and chemotherapy, locoregional recurrences and distant metastases occur at higher rates, and overall survival is decreased by 40% compared to HNSCC without PNI. In vitro studies of the pathways involved in HNSCC PNI have historically been challenging given the lack of a consistent, reproducible assay. Described here is the adaptation of the dorsal root ganglion (DRG) assay for the examination of PNI in HNSCC. In this model, DRG are harvested from the spinal column of a sacrificed nude mouse and placed within a semisolid matrix. Over the subsequent days, neurites are generated and grow in a radial pattern from the cell bodies of the DRG. HNSCC cell lines are then placed peripherally around the matrix and invade preferentially along the neurites toward the DRG. This method allows for rapid evaluation of multiple treatment conditions, with very high assay success rates and reproducibility.

Perineural invasion (PNI) is a common feature of head and neck squamous cell carcinoma (HNSCC), conferring lower survival rates. Its mechanisms are poorly understood. Utilizing neurites generated from murine dorsal root ganglia confined to a semisolid matrix, the pathways involved in the PNI of HNSCC cell lines can be investigated.

Perineural invasion (PNI) is found in approximately 40% of head and neck squamous cell carcinomas (HNSCC). Despite multimodal treatment with surgery, ...

Generation of High-Throughput Three-Dimensional Tumor Spheroids for Drug Screening

Cancer cells have routinely been cultured in two dimensions (2D) on a plastic surface. This technique, however, lacks the true environment a tumor mass is exposed to in vivo. Solid tumors grow not as a sheet attached to plastic, but instead as a collection of clonal cells in a three-dimensional (3D) space interacting with their neighbors, and with distinct spatial properties such as the disruption of normal cellular polarity. These interactions cause 3D-cultured cells to acquire morphological and cellular characteristics which are more relevant to in vivo tumors. Additionally, a tumor mass is in direct contact with other cell types such as stromal and immune cells, as well as the extracellular matrix from all other cell types. The matrix deposited is comprised of macromolecules such as collagen and fibronectin.
In an attempt to increase the translation of research findings in oncology from bench to bedside, many groups have started to investigate the use of 3D model systems in their drug development strategies. These systems are thought to be more physiologically relevant because they attempt to recapitulate the complex and heterogeneous environment of a tumor. These systems, however, can be quite complex, and, although amenable to growth in 96-well formats, and some now even in 384, they offer few choices for large-scale growth and screening. This observed gap has led to the development of the methods described here in detail to culture tumor spheroids in a high-throughput capacity in 1536-well plates. These methods represent a compromise to the highly complex matrix-based systems, which are difficult to screen, and conventional 2D assays. A variety of cancer cell lines harboring different genetic mutations are successfully screened, examining compound efficacy by using a curated library of compounds targeting the Mitogen-Activated Protein Kinase or MAPK pathway. The spheroid culture responses are then compared to the response of cells grown in 2D, and differential activities are reported. These methods provide a unique protocol for testing compound activity in a high-throughput 3D setting.

Across a wide variety of disease indications, more physiologically relevant models are being developed and implemented into drug discovery programs. The new model system described here demonstrates how three-dimensional tumor spheroids can be cultured and screened in a high-throughput 1536-well plate-based system to search for new oncology drugs.

Cancer cells have routinely been cultured in two dimensions (2D) on a plastic surface. This technique, however, lacks the true environment a tumor mass is ...

Live-Cell Imaging Assays to Study Glioblastoma Brain Tumor Stem Cell Migration and Invasion

Glioblastoma (GBM) is an aggressive brain tumor that is poorly controlled with the currently available treatment options. Key features of GBMs include rapid proliferation and pervasive invasion into the normal brain. Recurrence is thought to result from the presence of radio- and chemo-resistant brain tumor stem cells (BTSCs) that invade away from the initial cancerous mass and, thus, evade surgical resection. Hence, therapies that target BTSCs and their invasive abilities may improve the otherwise poor prognosis of this disease. Our group and others have successfully established and characterized BTSC cultures from GBM patient samples. These BTSC cultures demonstrate fundamental cancer stem cell properties such as clonogenic self-renewal, multi-lineage differentiation, and tumor initiation in immune-deficient mice. In order to improve on the current therapeutic approaches for GBM, a better understanding of the mechanisms of BTSC migration and invasion is necessary. In GBM, the study of migration and invasion is restricted, in part, due to the limitations of existing techniques which do not fully account for the in vitro growth characteristics of BTSCs grown as neurospheres. Here, we describe rapid and quantitative live-cell imaging assays to study both the migration and invasion properties of BTSCs. The first method described is the BTSC migration assay which measures the migration toward a chemoattractant gradient. The second method described is the BTSC invasion assay which images and quantifies a cellular invasion from neurospheres into a matrix. The assays described here are used for the quantification of BTSC migration and invasion over time and under different treatment conditions.

Here, we describe live-cell imaging techniques to quantitatively measure the migration and invasion of glioblastoma brain tumor stem cells over time and under multiple treatment conditions.

Glioblastoma (GBM) is an aggressive brain tumor that is poorly controlled with the currently available treatment options. Key features of GBMs include ...

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. ...

A Simple Migration/Invasion Workflow Using an Automated Live-cell Imager

Cancer cell mobility is crucial for the initiation of metastasis. Therefore, investigation of the cell movement and invasive capacity is of great significance. Migration assays provide basic insight of cell movement at a 2D level, whereas invasion assays are more physiologically relevant, mimicking in vivo cancer cell dislodgment from the original site and invading through the extracellular matrix. The current protocol provides a single workflow for migration and invasion assays. Together with the integrated automated microscopic camera for real-time HD images and built-in analysis module, it gives researchers a time-efficient, simple and reproducible experimental option. This protocol also includes substitutions for the consumables and alternative analysis methods for users to choose from.

The current protocol describes an integrated method investigating cancer cell migration and invasion on a single platform in real-time, providing an easily reproducible and time-efficient option to study cell mobility and morphology.

Cancer cell mobility is crucial for the initiation of metastasis. Therefore, investigation of the cell movement and invasive capacity is of great ...

Drug Screening of Primary Patient Derived Tumor Xenografts in Zebrafish

Patient derived xenograft models are critical in defining how different cancers respond to drug treatment in an in vivo system. Mouse models are the standard in the field, but zebrafish have emerged as an alternative model with several advantages, including the ability for high-throughput and low-cost drug screening. Zebrafish also allow for in vivo drug screening with large replicate numbers that were previously only obtainable with in vitro systems. The ability to rapidly perform large scale drug screens may open up the possibility for personalized medicine with rapid translation of results back to clinic. Zebrafish xenograft models could also be used to rapidly screen for actionable mutations based on tumor response to targeted therapies or to identify new anti-cancer compounds from large libraries. The current major limitation in the field has been quantifying and automating the process so that drug screens can be done on a larger scale and be less labor-intensive. We have developed a workflow for xenografting primary patient samples into zebrafish larvae and performing large scale drug screens using a fluorescence microscope equipped imaging unit and automated sampler unit. This method allows for standardization and quantification of engrafted tumor area and response to drug treatment across large numbers of zebrafish larvae. Overall, this method is advantageous over traditional cell culture drug screening as it allows for growth of tumor cells in an in vivo environment throughout drug treatment, and is more practical and cost-effective than mice for large scale in vivo drug screens.

Zebrafish xenograft models allow for high-throughput drug screening and fluorescent imaging of human cancer cells in an in vivo microenvironment. We developed a workflow for large scale, automated drug screening on patient-derived leukemia samples in zebrafish using an automated fluorescence microscope equipped imaging unit.

Patient derived xenograft models are critical in defining how different cancers respond to drug treatment in an in vivo system. Mouse models are the ...

Impedance-based Real-time Measurement of Cancer Cell Migration and Invasion

Cancer arises due to uncontrolled proliferation of cells initiated by genetic instability, mutations, and environmental and other stress factors. These acquired abnormalities in complex, multilayered molecular signaling networks induce aberrant cell proliferation and survival, extracellular matrix degradation, and metastasis to distant organs. Approximately 90% of cancer-related deaths are estimated to be caused by the direct or indirect effects of metastatic dissemination. Therefore, it is important to establish a highly reliable, comprehensive system to characterize cancer cell behaviors upon genetic and environmental manipulations. Such a system can give a clear understanding of the molecular regulation of cancer metastasis and the opportunity for successful development of stratified, precise therapeutic strategies. Hence, accurate determination of cancer cell behaviors such as migration and invasion with gain or loss of function of gene(s) allows assessment of the aggressive nature of cancer cells. The real-time measurement system based on cell impedance enables researchers to continually acquire data during a whole experiment and instantly compare and quantify the results under various experimental conditions. Unlike conventional methods, this method does not require fixation, staining, and sample processing to analyze cells that migrate or invade. This method paper emphasizes detailed procedures for real-time determination of migration and invasion of glioblastoma cancer cells.

Cancer is a lethal disease due to its ability to metastasize to different organs. Determining the ability of cancer cells to migrate and invade under various treatment conditions is crucial to assessing therapeutic strategies. This protocol presents a method to assess the real-time metastatic abilities of a glioblastoma cancer cell line.&#160;

Cancer arises due to uncontrolled proliferation of cells initiated by genetic instability, mutations, and environmental and other stress factors. These ...

Evaluating Cell Death Using Cell-Free Supernatant of Probiotics in Three-Dimensional Spheroid Cultures of Colorectal Cancer Cells

This manuscript describes a protocol to evaluate cancer cell deaths in three dimensional (3D) spheroids of multicellular types of cancer cells using supernatants from Lactobacillus fermentum cell culture, considered as probiotics cultures. The use of 3D cultures to test Lactobacillus cell-free supernatant (LCFS) are a better option than testing in 2D monolayers, especially as L. fermentum can produce anti-cancer effects within the gut. L. fermentum supernatant was identified to possess increased anti-proliferative effects against several colorectal cancer (CRC) cells in 3D culture conditions. Interestingly, these effects were strongly related to the culture model, demonstrating the notable ability of L. fermentum to induce cancer cell death. Stable spheroids were generated from diverse CRCs (colorectal cancer cells) using the protocol presented below. This protocol of generating 3D spheroid is time saving and cost effective. This system was developed to easily investigate the anti-cancer effects of LCFS in multiple types of CRC spheroids. As expected, CRC spheroids treated with LCFS strongly induced cell death during the experiment and expressed specific apoptosis molecular markers as analyzed by qRT-PCR, western blotting, and FACS analysis. Therefore, this method is valuable for exploring cell viability and evaluating the efficacy of anti-cancer drugs.

Here methods are presented to understand anti-cancer effects of Lactobacillus cell-free supernatant (LCFS). Colorectal cancer cell lines show cell deaths when treated with LCFS in 3D cultures. The process of generating spheroids can be optimized depending on the scaffold and the analysis methods presented are useful for evaluating the involved signaling pathways.

This manuscript describes a protocol to evaluate cancer cell deaths in three dimensional (3D) spheroids of multicellular types of cancer cells using ...

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 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 ...