The authors thank the First Affiliated Hospital of Gannan Medical University for supporting this work.&#160;This work was supported by the National Natural Science Foundation of China (grant numbers 82260422).

Human liver cancer tissue was collected from patients diagnosed with hepatic malignancy at the First Affiliated Hospital of Gannan Medical University. All patients signed an informed consent form, and the collection of human tissue samples was approved by the ethics committee of the First Affiliated Hospital of Gannan Medical University. See the Table of Materials for details related to all materials, equipment, and software used in this protocol.
1. Preparation
<ol>
	<li>Place the transference decoloring shaker in the incubator and set the temperature at 37 &#176;C. See Figure 1 for all the other needed equipment.</li>
	<li>Clean the scalpel and forceps by spraying them with 75% alcohol.</li>
	<li>Prepare the digestive solution by measuring 6 mg of collagenase D (4 mg/mL) and 24 &#181;L of DNase &#921; (80 U/mL) and adding them to 1.5 mL of RPMI-1640 basic medium. Mix by gentle inversion until the additives are completely dissolved.</li>
	<li>In advance, moisten 70 &#181;m and 0.22 &#181;m cell strainers with 1x phosphate-buffered saline (PBS).</li>
	<li>Place a 100 mm sterile cell culture dish on the icebox to hold the liver tissues after defrosting.</li>
	<li>Within 15 min after hepatocellular carcinoma tissue isolation, rinse off the blood on the surface of the tissue block with PBS, transfer the tissue into a sterile frozen tube, and store it at &#8722;80 &#176;C until the experiment for not more than 2 weeks.</li>
</ol>
2. Tissue dissociation
<ol>
	<li>Remove the tissue sample from the &#8722;80 &#176;C freezer and place approximately 400 mg of the tissue-cut into 2 mm x 2 mm x 2 mm fragments-into the 10 cm cell culture dish on the icebox.</li>
	<li>Move the tissue into a 6-well plate with 1.5 mL of the digestive solution; then, place the plate on the transference decoloring shaker (20 rpm/min) to incubate for 20 min at 37 &#176;C for complete dissociation of the liver cancer tissue and release of the sEVs.</li>
	<li>Remove the 6-well plate from the incubator and place it on the icebox. Add 80 &#181;L of phosphatase inhibitor and 200 &#181;L of complete protease inhibitor solution to stop the digestion.</li>
	<li>Transfer the digestive solution to the 70 &#181;m cell strainer and filter it slowly to remove any large tissue debris. Collect the filtrate and place it in a 2 mL centrifuge tube.</li>
</ol>
3. Differential ultracentrifugation
NOTE: Perform all the centrifugation steps at 4 &#176;C.
<ol>
	<li>Centrifuge the filtrate at 500 &#215; g for 10 min and collect the supernatant in a new 2 mL centrifuge tube. Most of the small tissue debris can then be removed.</li>
	<li>Centrifuge the supernatant at 3,000 &#215; g for 20 min to remove cell debris. Carefully transfer the supernatant to a new centrifuge tube until the tip of the pipette is about to touch the white substance on the surface.</li>
	<li>Centrifuge the remaining liquid at 3,000 &#215; g for 3 min; then, aspirate the supernatant to facilitate the collection of vesicles. To ensure the purity of the sEVs, make sure that the white substance is not aspirated.</li>
	<li>Centrifuge the collected supernatant at 12,000 &#215; g for 20 min and transfer 900 &#181;L of the supernatant to a 4.7 mL ultracentrifuge tube. Centrifuge the remaining liquid at 12,000 &#215; g for 3 min and then collect and mix both supernatants into the same ultracentrifuge tube. Fill the tube completely with PBS.</li>
	<li>Centrifuge the supernatants at 100,000 &#215; g for 60 min. Discard the supernatant and resuspend the pellet by filling the ultracentrifuge tube with PBS and centrifuging again at 100,000 &#215; g for 60 min. Resuspend the pellet with 50 &#181;L of PBS.</li>
	<li>Aspirate the sEV suspension using a 1 mL sterile syringe and filter it through a 0.22 &#181;m membrane filter. Collect the filtrate in a 600 &#181;L centrifuge tube and store it at &#8722;80 &#176;C for further analysis.</li>
</ol>
4. Evaluation of enrichment quality
<ol>
	<li>Observe the morphology of the sEVs under a transmission electron microscope.
	<ol>
		<li>Then, drop 10 &#181;L of the sEV sample onto a copper net, incubate at room temperature for 10 min, and clean it with sterile distilled water, using absorbent paper to remove excess liquid.</li>
		<li>Drop 10 &#181;L of 2% uranyl acetate onto the copper net for negative staining for 1 min. Use filter paper to absorb the liquid on the surface of the copper net and dry it for 2 min under an incandescent lamp.</li>
		<li>Observe the copper mesh under a transmission electron microscope and image at 80 kV.</li>
	</ol>
	</li>
	<li>Use a nanoparticle flow cytometer to determine the size distribution and purity of the sEVs.
	<ol>
		<li>Before the machine is started, prepare tubes containing 200 &#181;L of quality control, 200 &#181;L of silica nanospheres, 2 x 200 &#181;L of ultrapure water, 2 x 200 &#181;L of cleaning solution, and 200 &#181;L of PBS. 
		NOTE: Before testing the sEV samples, it is necessary to carry out quality control on the instrument and test the particle size standard (the size distribution must be calculated using standard curves generated with several nanomicrospheres of different diameters [68-155 nm] under the same detection condition). QC beads and silica nanospheres were diluted 100x with ultrapure water in a total volume of 200 &#181;L.</li>
		<li>Check the volume of the cleaning solution (&#62;10 mL) and note the difference between the levels of the sheath liquid and the waste liquid (20-30 cm).</li>
		<li>Turn off the main power supply of the instrument; after 20 s, turn on the computer and wait for the beeps indicating that the instrument is properly connected to run the software.</li>
		<li>Click on Start Up to turn on the camera, laser, and air pump.</li>
		<li>Click on Sheath Flow-Start Up, and place ultrapure water on the loading platform. After 4 min (instrument&#39;s countdown), click on Sample-Boosting | Sample-Unload.</li>
		<li>After 30 s, place the blank tube on the loading platform and click on Sample-Boosting | Sample-Unload. Then, place the tube holding the ultrapure water on the loading platform, and, simultaneously, click on Sample-Boosting | Sheath Flow-Purge.</li>
		<li>Click on Manual Operation and place the particle concentration tube on the loading platform. Then, click on Sample-Boosting for 1 min and simultaneously select 250 nm Std FL SiNPs quality control in &#34;SAMP. Inf.&#34;</li>
		<li>Click on Sample-Sampling and turn the detector on by clicking on SPCM. 
		NOTE: At this point, the real-time signal waveform can be seen.</li>
		<li>Click on Auto Sampling and enter 1.0 into Sampling SET to fix the pressure at 1 KPa. Click on the toolbar and select Large Signal.</li>
		<li>Adjust the horizontal position of the laser and set the laser to 2 &#181;m; then, click on L or R to make sure that the signal is strong and uniform.</li>
		<li>Click on Time to Record to collect the data, which will automatically jump to Buffer when finished. Then, save the data in a Naf File and click on Sample-Unload.</li>
		<li>Place the cleaning solution tube on the loading platform, click on Sample-Boosting, and after 1 min, click on Sample-Unload. Use ultrapure water to remove the residual cleaning solution from the capillary tip.</li>
		<li>Place the particle-size standard tube on the loading platform and click on Sample-Boosting for 1 min.</li>
		<li>Select 68-155 nm Std FL SiNPs quality control in &#34;SAMP. Inf&#34; and click on Sample-Sampling. Then, click on the toolbar and select Small Signal.</li>
		<li>Click on Time to Record to collect the data, which will automatically jump to Buffer when finished. Then, save the data in a Naf File and click on Sample-Unload.</li>
		<li>Place the cleaning solution tube on the loading platform, click on Sample-Boosting, and click on Sample-Unload after 1 min. Use ultrapure water to remove the residual cleaning solution from the capillary tip.</li>
		<li>Place the PBS tube on the loading platform; click on Sample-Boosting for 1 min.</li>
		<li>Select 68-155 nm Std FL SiNPs quality control in &#34;SAMP. Inf&#34; and click on Sample-Sampling. Then, click on the toolbar and select Small Signal.</li>
		<li>Click on Time to Record to collect data, which will automatically jump to Buffer when finished. Save the data in a Naf File and click on Sample-Unload.</li>
		<li>Place the cleaning solution tube on the loading platform, click on Sample-Boosting and Sample-Unload after 1 min. Use ultrapure water to remove residual cleaning solution from the capillary tip.</li>
		<li>Check the sample information as described earlier in steps 4.2.17-4.2.20; change the PBS (step 4.2.17) to the sEV sample and analyze the data.</li>
	</ol>
	</li>
	<li>Further identify the sEVs by western blot.
	<ol>
		<li>Determine the protein concentrations of the sEVs and tissues by using the BCA protein quantification kit according to the manufacturer&#39;s instructions.</li>
		<li>Calculate the loading volume of sEVs (e.g., for 5 &#181;g of protein per well) based on these quantitative results. Add loading buffer in a 1:4 ratio and vortex the mixture.</li>
		<li>After denaturation in a 100 &#176;C metal bath (dry thermostat) for 10 min, separate the protein on a 12% polyacrylamide gel at 60 V for 80 min.</li>
		<li>Transfer the gel onto a 0.22 &#181;m polyvinylidene difluoride membrane at 220 mA for 2 h using transfer buffer (25 mM Tris, 192 mM glycine, 20% methanol).</li>
		<li>Block the membrane with 5% nonfat dry milk in Tris-buffered saline Tween (TBST) for 1 h at room temperature and incubate with primary antibody (rabbit monoclonal anti-human CD9 antibody, rabbit monoclonal anti-human CD63 antibody, rabbit monoclonal anti-human TSG101 antibody, mouse monoclonal anti-human GM130 antibody) overnight at 4 &#176;C. Dilute the primary antibodies in 5% nonfat milk at 1:1,000.</li>
		<li>Following three washes with TBST, incubate the membrane with horseradish peroxidase (HRP)-conjugated secondary antibody at room temperature for 1 h.</li>
		<li>Detect the HRP-linked antibody using ECL blotting substrate, and then collect and analyze the images.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Isaac, R., Reis, F. C. G., Ying, W., Olefsky, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exosomes+as+mediators+of+intercellular+crosstalk+in+metabolism.">Exosomes as mediators of intercellular crosstalk in metabolism.</a> Cell Metabolism. 33 (9), 1744-1762 (2021).</li><li>Hou, R., 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=Advances+in+exosome+isolation+methods+and+their+applications+in+proteomic+analysis+of+biological+samples.">Advances in exosome isolation methods and their applications in proteomic analysis of biological samples.</a> Analytical and Bioanalytical Chemistry. 411 (21), 5351-5361 (2019).</li><li>Zhang, L., Yu, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exosomes+in+cancer+development,+metastasis,+and+immunity.">Exosomes in cancer development, metastasis, and immunity.</a> Biochimica et Biophysica Acta - Reviews on Cancer. 1871 (2), 455-468 (2019).</li><li>Yang, D., 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=and+perspective+on+exosome+isolation+-+Efforts+for+efficient+exosome-based+theranostics.">and perspective on exosome isolation - Efforts for efficient exosome-based theranostics.</a> Theranostics. 10 (8), 3684-3707 (2020).</li><li>Crescitelli, R., L&#228;sser, C., L&#246;tvall, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+characterization+of+extracellular+vesicle+subpopulations+from+tissues.">Isolation and characterization of extracellular vesicle subpopulations from tissues.</a> Nature Protocols. 16 (3), 1548-1580 (2021).</li><li>Crescitelli, R., 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=Subpopulations+of+extracellular+vesicles+from+human+metastatic+melanoma+tissue+identified+by+quantitative+proteomics+after+optimized+isolation.">Subpopulations of extracellular vesicles from human metastatic melanoma tissue identified by quantitative proteomics after optimized isolation.</a> Journal of Extracellular Vesicles. 9 (1), 1722433 (2020).</li><li>Jang, S. C., 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=Mitochondrial+protein+enriched+extracellular+vesicles+discovered+in+human+melanoma+tissues+can+be+detected+in+patient+plasma.">Mitochondrial protein enriched extracellular vesicles discovered in human melanoma tissues can be detected in patient plasma.</a> Journal of Extracellular Vesicles. 8 (1), 1635420 (2019).</li><li>Muralidharan-Chari, V., 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=ARF6-regulated+shedding+of+tumor+cell-derived+plasma+membrane+microvesicles.">ARF6-regulated shedding of tumor cell-derived plasma membrane microvesicles.</a> Current Biology. 19 (22), 1875-1885 (2009).</li><li>Matejovi&#269;, A., Wakao, S., Kitada, M., Kushida, Y., Dezawa, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+separation+methods+for+tissue-derived+extracellular+vesicles+in+the+liver,+heart,+and+skeletal+muscle.">Comparison of separation methods for tissue-derived extracellular vesicles in the liver, heart, and skeletal muscle.</a> FEBS Open Bio. 11 (2), 482-493 (2021).</li><li>Zhou, X., 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=Brown+adipose+tissue-derived+exosomes+mitigate+the+metabolic+syndrome+in+high+fat+diet+mice.">Brown adipose tissue-derived exosomes mitigate the metabolic syndrome in high fat diet mice.</a> Theranostics. 10 (18), 8197-8210 (2020).</li><li>Chen, 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=Comparison+of+the+variability+of+small+extracellular+vesicles+derived+from+human+liver+cancer+tissues+and+cultured+from+the+tissue+explants+based+on+a+simple+enrichment+method.">Comparison of the variability of small extracellular vesicles derived from human liver cancer tissues and cultured from the tissue explants based on a simple enrichment method.</a> Stem Cell Reviews and Reports. 18 (3), 1067-1077 (2022).</li><li>Fang, T., 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=Tumor-derived+exosomal+miR-1247-3p+induces+cancer-associated+fibroblast+activation+to+foster+lung+metastasis+of+liver+cancer.">Tumor-derived exosomal miR-1247-3p induces cancer-associated fibroblast activation to foster lung metastasis of liver cancer.</a> Nature Communications. 9 (1), 1247-1243 (2018).</li><li>Huang, X., 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=RNA+sequencing+of+plasma+exosomes+revealed+novel+functional+long+noncoding+RNAs+in+hepatocellular+carcinoma.">RNA sequencing of plasma exosomes revealed novel functional long noncoding RNAs in hepatocellular carcinoma.</a> Cancer Science. 111 (9), 3338-3349 (2020).</li><li>Chen, L., 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=HCC-derived+exosomes+elicit+HCC+progression+and+recurrence+by+epithelial-mesenchymal+transition+through+MAPK/ERK+signalling+pathway.">HCC-derived exosomes elicit HCC progression and recurrence by epithelial-mesenchymal transition through MAPK/ERK signalling pathway.</a> Cell Death &amp; Disease. 9 (5), 513 (2018).</li><li>Jingushi, 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=Extracellular+vesicles+isolated+from+human+renal+cell+carcinoma+tissues+disrupt+vascular+endothelial+cell+morphology+via+azurocidin.">Extracellular vesicles isolated from human renal cell carcinoma tissues disrupt vascular endothelial cell morphology via azurocidin.</a> International Journal of Cancer. 142 (3), 607-617 (2018).</li><li>Camino, T., 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=Deciphering+adipose+tissue+extracellular+vesicles+protein+cargo+and+its+role+in+obesity.">Deciphering adipose tissue extracellular vesicles protein cargo and its role in obesity.</a> International Journal of Molecular Sciences. 21 (24), 9366 (2020).</li></ol>

The authors have no conflicts of interest to disclose.

This protocol describes a repeatable method for extracting sEVs from liver cancer tissue. High-quality sEVs are obtained by sharp tissue isolation, treatment with digestive enzymes, differential ultracentrifugation, and 0.22 &#181;m filter membrane filtration and purification. For downstream analysis, it is extremely important to ensure the high purity of the sEVs. In the process of differential centrifugation, a layer of white substances (unknown composition) will appear on the surface of the supernatant. As this layer ...

Small extracellular vesicles (sEVs) are approximately 30 nm to 150 nm in diameter and are secreted by various cells1. They can communicate with tissue cells and regulate the local or distant microenvironment by transporting important biological molecules such as lipids, proteins, DNA, and RNA to various organs, tissues, cells, and intracellular parts. Thus, they can also change the behavior of recipient cells2,3. The isolation and purification of specific sEVs is an essential prerequisite to studying their biological behavior during the development and course of disease. Differential ultracentrifugation-regarded as the gold standard-is commonly used to separate sEVs from the tissues in which they normally reside4. Tissue debris, cell debris, large vesicles, and apoptotic bodies can be removed by this technique, leaving only the sEVs.
Collagenase D and DNase I have been shown not to affect the molecular characteristics of cells or vesicles, with the properties of both enzymes contributing to the release of vesicles in the extracellular matrix 5. These enzymes have been used to extract sEVs from human metastatic melanoma tissue, colon cancer tissue, and colonic mucosal tissue5,6,7. However, the concentration and digestion time of collagenase D and DNase I in these methods differ, leading to inconsistent conclusions. To avoid the coprecipitation of other subtypes of sEVs, researchers have removed larger extracellular vesicles (0.1 &#181;m or 0.2 &#181;m in diameter) by filtration and/or differential centrifugation8. Depending on the source tissue, different methods of isolation and purification may be required9,10.
Using the traditional differential ultracentrifugation method to extract sEVs from liver tissue results in a layer of white matter on the surface of the supernatant, without any way of determining its properties. In a previous study11, this layer of white matter was found to affect the purity of the sEVs. Although the particle number and protein concentration of samples isolated by the traditional method were higher than those of the current method, the coefficient of variation was large, possibly because many pollutants can lead to poor repeatability of the results. That is, using detergent (i.e., detecting the solubility of particles in 1% Triton X-100), we found that the purity of sEVs obtained by this method was greater. Hence, we use this method to isolate and purify sEVs derived from colorectal cancer tissue for proteomic research.
At present, the research on sEVs in liver cancer is focused mainly on serum, plasma, and the cell culture&#39;s supernatant12,13,14. However, sEVs derived from liver cancer tissue can more accurately reflect the physiologic pathology and the surrounding microenvironment of liver cancer and effectively avoid the degradation and pollution of other EVs15,16. With the use of differential ultracentrifugation, this method can enrich the yield and obtain high-quality sEVs, providing an important basis for the further study of liver cancer. This method enables the liver cancer tissue to be separated by sharp separation and to be dissociated by collagenase D and DNase I. Then, the cellular debris, large vesicles, and apoptotic bodies are further removed by filtration and differential ultracentrifugation. Finally, the sEVs are isolated and purified for later studies.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.22 &#181;m Membrane Filter Unit</td>
			<td>Millex</td>
			<td>SLGPR33RB</td>
			<td></td>
		</tr>
		<tr>
			<td>1 mL Sterile syringe</td>
			<td>Hubei Xianming Medical Instrument Company</td>
			<td>YL01329</td>
			<td></td>
		</tr>
		<tr>
			<td>2% Uranyl Acetate</td>
			<td>Electron Microscopy Sciences</td>
			<td>22400-2</td>
			<td></td>
		</tr>
		<tr>
			<td>4.7 mL Centrifuge Tube</td>
			<td>Beckman Coulter</td>
			<td>361621</td>
			<td></td>
		</tr>
		<tr>
			<td>6-well Cell cuture plate</td>
			<td>LABSELECT</td>
			<td>11110</td>
			<td></td>
		</tr>
		<tr>
			<td>50 mL Beaker</td>
			<td>Tianjin Kangyiheng Experimental Instrument Sales Company</td>
			<td>CF2100800</td>
			<td></td>
		</tr>
		<tr>
			<td>70 &#181;m Cell strainer</td>
			<td>Biosharp</td>
			<td>BS-70-XBS</td>
			<td></td>
		</tr>
		<tr>
			<td>100 mm Cell culture dish</td>
			<td>CELL TER</td>
			<td>CS016-0128</td>
			<td></td>
		</tr>
		<tr>
			<td>600 &#181;L Centrifuge tube</td>
			<td>Axygen</td>
			<td>MCT060C</td>
			<td></td>
		</tr>
		<tr>
			<td>BCA protein quantification kit</td>
			<td>Thermo Fisher</td>
			<td>RJ240544</td>
			<td></td>
		</tr>
		<tr>
			<td>Beckman Coulter Optima-Max-TL</td>
			<td>Beckman&#160;</td>
			<td>A95761</td>
			<td></td>
		</tr>
		<tr>
			<td>BioRad Mini trans-blot</td>
			<td>Bio-Rad</td>
			<td>1703930</td>
			<td></td>
		</tr>
		<tr>
			<td>BioRad Mini-Protean</td>
			<td>Bio-Rad</td>
			<td>1645050</td>
			<td></td>
		</tr>
		<tr>
			<td>CD63 Antibody</td>
			<td>Abcam</td>
			<td>ab134045</td>
			<td></td>
		</tr>
		<tr>
			<td>CD9 Antibody</td>
			<td>Abcam</td>
			<td>ab263019</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge 5430R</td>
			<td>Eppendorf</td>
			<td>5428HQ527333</td>
			<td></td>
		</tr>
		<tr>
			<td>Cleaning Solution</td>
			<td>NanoFCM</td>
			<td>C1801</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagenase D</td>
			<td>Roche</td>
			<td>11088866001</td>
			<td></td>
		</tr>
		<tr>
			<td>Copper net</td>
			<td>Henan Zhongjingkeyi Technology Company</td>
			<td>DJZCM-15-N1</td>
			<td></td>
		</tr>
		<tr>
			<td>Dry Thermostat</td>
			<td>Hangzhou allsheng instruments company</td>
			<td>AS-01030-00</td>
			<td></td>
		</tr>
		<tr>
			<td>FITC Anti Human CD9 Antibody</td>
			<td>Elabscience</td>
			<td>E-AB-F1086C</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycine</td>
			<td>Solarbio</td>
			<td>G8200</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat horseradish peroxidase (HRP)-coupled secondary anti-mouse antibody&#160;</td>
			<td>Proteintech</td>
			<td>SA00001-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat horseradish peroxidase (HRP)-coupled secondary anti-rabbit antibody&#160;</td>
			<td>Proteintech</td>
			<td>SA00001-2</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Shanghai Zhenxing Chemical Company</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nanoparticle flow cytometer</td>
			<td>NanoFCM INC</td>
			<td>FNAN30E20112368</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphatase inhibitors(PhosSTOP)</td>
			<td>Roche</td>
			<td>4906845001</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline(PBS)</td>
			<td>Servicebio</td>
			<td>G4202</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyvinylidene Difluoride Membrane</td>
			<td>Solarbio</td>
			<td>ISEQ00010</td>
			<td></td>
		</tr>
		<tr>
			<td>QC Beads</td>
			<td>NanoFCM</td>
			<td>QS2502</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI-1640 basic medium</td>
			<td>Biological Industries&#160;</td>
			<td>C11875500BT</td>
			<td></td>
		</tr>
		<tr>
			<td>Scalpel</td>
			<td>Guangzhou Kehua Trading Company</td>
			<td>NN-0623-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Silica Nanospheres</td>
			<td>NanoFCM</td>
			<td>S16M-Exo</td>
			<td></td>
		</tr>
		<tr>
			<td>Transference Decoloring Shaker TS-8</td>
			<td>Kylin-Bell</td>
			<td>E0018</td>
			<td></td>
		</tr>
		<tr>
			<td>Transmission Electron Microscope</td>
			<td>Thermo Scientific</td>
			<td>Talos L120C</td>
			<td></td>
		</tr>
		<tr>
			<td>Tris</td>
			<td>Solarbio</td>
			<td>T8060</td>
			<td></td>
		</tr>
		<tr>
			<td>TSG101 Antibody</td>
			<td>Proteintech</td>
			<td>28283-1-AP</td>
			<td></td>
		</tr>
		<tr>
			<td>Tweezer</td>
			<td>Guangzhou Lige Technology Company</td>
			<td>LG01-105-4X</td>
			<td></td>
		</tr>
	</tbody>
</table>

an enrichment method for small extracellular vesicles derived from liver cancer tissue

Small extracellular vesicles (sEVs) derived from tissue can reflect the functional status of the source cells and the characteristics of the tissue's interstitial space. The efficient enrichment of these sEVs is an important prerequisite to the study of their biological function and a key to the development of clinical detection techniques and therapeutic carrier technology. It is difficult to isolate sEVs from tissue because they are usually heavily contaminated. This study provides a method for the rapid enrichment of high-quality sEVs from liver cancer tissue. The method involves a four-step process: the incubation of digestive enzymes (collagenase D and DNase &#921;) with tissue, filtration through a 70 &#181;m cell strainer, differential ultracentrifugation, and filtration through a 0.22 &#181;m membrane filter. Owing to the optimization of the differential ultracentrifugation step and the addition of a filtration step, the purity of the sEVs obtained by this method is higher than that achieved by classic differential ultracentrifugation. It provides an important methodology and supporting data for the study of tissue-derived sEVs.

sEVs from human liver cancer tissues have played a crucial role in the diagnosis, treatment, and prognosis of patients with liver cancer. This method used common laboratory instruments to isolate and purify sEVs derived from liver cancer tissues; this may provide methodologic support for the study of sEVs. Figure 2 illustrates the general process of enriching sEVs from liver cancer tissues. sEVs in the intercellular spaces of tissues are fully released through tissue cutting and enzymatic hy...

Watch this Scientific Journal Video about An Enrichment Method for Small Extracellular Vesicles Derived from Liver Cancer Tissue at JoVE.com

An Enrichment Method for Small Extracellular Vesicles Derived from Liver Cancer Tissue

Here we describe the enrichment of small extracellular vesicles derived from liver cancer tissue through an optimized differential ultracentrifugation method.

Small extracellular vesicles (sEVs) derived from tissue can reflect the functional status of the source cells and the characteristics of the tissue's ...

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Research

JoVE Journal

Cancer Research

1.2K Views.  Gannan Medical University. Here we describe the enrichment of small extracellular vesicles derived from liver cancer tissue through an optimized differential ultracentrifugation method.

Video: An Enrichment Method for Small Extracellular Vesicles Derived from Liver Cancer Tissue

Extraction of Extracellular Vesicles from Whole Tissue

Circulating and interstitial small membrane-bound extracellular vesicles (EVs) represent promising targets for the development of novel diagnostic or prognostic biomarker assays, and likely serve as important players in the progression of a vast spectrum of diseases. Current research is focused on the characterization of vesicles secreted from multiple cell and tissue types in order to better understand the role of EVs in the pathogenesis of conditions including neurodegeneration, inflammation, and cancer. However, globally consistent and reproducible techniques to isolate and purify vesicles remain in progress. Moreover, methods for extraction of EVs from solid tissue ex vivo are scarcely described. Here, we provide a detailed protocol for extracting small EVs of interest from whole fresh or frozen tissues, including brain and tumor specimens, for further characterization. We demonstrate the adaptability of this method for multiple downstream analyses, including electron microscopy and immunophenotypic characterization of vesicles, as well as quantitative mass spectrometry of EV proteins.

Here, we provide a detailed protocol to isolate small extracellular vesicles (EVs) from whole tissues, including brain and tumor specimens. This method offers a reproducible technique to extract EVs from solid tissue for further downstream analyses.

Circulating and interstitial small membrane-bound extracellular vesicles (EVs) represent promising targets for the development of novel diagnostic or ...

Studying Normal Tissue Radiation Effects using Extracellular Matrix Hydrogels

Radiation is a therapy for patients with triple negative breast cancer. The effect of radiation on the extracellular matrix (ECM) of healthy breast tissue and its role in local recurrence at the primary tumor site are unknown. Here we present a method for the decellularization, lyophilization, and fabrication of ECM hydrogels derived from murine mammary fat pads. Results are presented on the effectiveness of the decellularization process, and rheological parameters were assessed. GFP- and luciferase-labeled breast cancer cells encapsulated in the hydrogels demonstrated an increase in proliferation in irradiated hydrogels. Finally, phalloidin conjugate staining was employed to visualize cytoskeleton organization of encapsulated tumor cells. Our goal is to present a method for fabricating hydrogels for in vitro study that mimic the in vivo breast tissue environment and its response to radiation in order to study tumor cell behavior.

This protocol presents a method for decellularization and subsequent hydrogel formation of murine mammary fat pads following ex vivo irradiation.

Radiation is a therapy for patients with triple negative breast cancer. The effect of radiation on the extracellular matrix (ECM) of healthy breast tissue ...

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells

Cutaneous melanoma is well known as the most aggressive skin cancer. Although the risk factors and major genetic alterations continue to be documented with increasing depth, the incidence rate of cutaneous melanoma has shown a rapid and continuous increase during recent decades. In order to find effective preventative methods, it is important to understand the early steps of melanoma initiation in the skin. Previous data has demonstrated that follicular melanocyte stem cells (MCSCs) in the adult skin tissues can act as melanoma cells of origin when expressing oncogenic mutations and genetic alterations. Tumorigenesis arising from melanoma-prone MCSCs can be induced when MCSCs transition from a quiescent to active state. This transition in melanoma-prone MCSCs can be promoted by the modulation of either hair follicle stem cells&#39; activity state or through extrinsic environmental factors such as ultraviolet-B (UV-B). These factors can be artificially manipulated in the laboratory by chemical depilation, which causes transition of hair follicle stem cells and MCSCs from a quiescent to active state, and by UV-B exposure using a benchtop light. These methods provide successful spatial and temporal control of cutaneous melanoma initiation in the murine dorsal skin. Therefore, these in vivo model systems will be valuable to define the early steps of cutaneous melanoma initiation and could be used to test potential methods for tumor prevention.

The following procedure describes a method for spatial and temporal control of melanocytic tumor initiation in murine dorsal skin, using a genetically engineered mouse model. This protocol describes macroscopic as well as microscopic cutaneous melanoma initiation.

Cutaneous melanoma is well known as the most aggressive skin cancer. Although the risk factors and major genetic alterations continue to be documented ...

Isolation of Exosome-Enriched Extracellular Vesicles Carrying Granulocyte-Macrophage Colony-Stimulating Factor from Embryonic Stem Cells

Embryonic stem cells (ESCs) are pluripotent stem cells capable of self-renewal and differentiation into all types of embryonic cells. Like many other cell types, ESCs release small membrane vesicles, such as exosomes, to the extracellular environment. Exosomes serve as essential mediators of intercellular communication and play a basic role in many (patho)physiological processes. Granulocyte-macrophage colony-stimulating factor (GM-CSF) functions as a cytokine to modulate the immune response. The presence of GM-CSF in exosomes has the potential to boost their immune-regulatory function. Here, GM-CSF was stably overexpressed in the murine ESC cell line ES-D3. A protocol was developed to isolate high-quality exosome-enriched extracellular vesicles (EVs) from ES-D3 cells overexpressing GM-CSF. Isolated exosome-enriched EVs were characterized by a variety of experimental approaches. Importantly, significant amounts of GM-CSF were found to be present in exosome-enriched EVs. Overall, GM-CSF-bearing exosome-enriched EVs from ESCs might function as cell-free vesicles to exert their immune-regulatory activities.

This study describes a method to isolate exosome-enriched extracellular vesicles carrying immune-stimulatory granulocyte macrophage colony-stimulating factors from embryonic stem cells.

Embryonic stem cells (ESCs) are pluripotent stem cells capable of self-renewal and differentiation into all types of embryonic cells. Like many other cell ...

Studying Triple Negative Breast Cancer Using Orthotopic Breast Cancer Model

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with limited therapeutic options. When compared to patients with less aggressive breast tumors, the 5-year survival rate of TNBC patients is 77% due to their characteristic drug-resistant phenotype and metastatic burden. Toward this end, murine models have been established aimed at identifying novel therapeutic strategies limiting TNBC tumor growth and metastatic spread. This work describes a practical guide for the TNBC orthotopic model where MDA-MB-231 breast cancer cells suspended in a basement membrane matrix are implanted in the fourth mammary fat pad, which closely mimics the cancer cell behavior in humans. Measurement of tumors by caliper, lung metastasis assessment via in vivo and ex vivo imaging, and molecular detection are discussed. This model provides an excellent platform to study therapeutic efficacy and is especially suitable for the study of the interaction between the primary tumor and distal metastatic sites.

This work presets an advanced protocol to accurately assess tumor loading by detection of green fluorescent protein and bioluminescence signals as well as the integration of quantitative molecular detection technique.

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with limited therapeutic options. When compared to patients with less ...

Sequencing Small Non-coding RNA from Formalin-fixed Tissues and Serum-derived Exosomes from Castration-resistant Prostate Cancer Patients

Ablation of androgen receptor (AR) signaling by androgen deprivation is the goal of the first line of therapy for prostate cancer that initially results in cancer regression. However, in a significant number of cases, the disease progresses to advanced, castration-resistant prostate cancer (CRPC), which has limited therapeutic options and is often aggressive. Distant metastasis is mostly observed at this stage of the aggressive disease. CRPC is treated by a second generation of AR pathway inhibitors that improve survival initially, followed by the emergence of therapy resistance. Neuroendocrine prostate cancer (NEPC) is a rare variant of prostate cancer (PCa) that often develops as a result of therapy resistance via a transdifferentiation process known as neuroendocrine differentiation (NED), wherein PCa cells undergo a lineage switch from adenocarcinomas and show increased expression of neuroendocrine (NE) lineage markers. In addition to the genomic alterations that drive the progression and transdifferentiation to NEPC, epigenetic factors and microenvironmental cues are considered essential players in driving disease progression. This manuscript provides a detailed protocol to identify the epigenetic drivers (i.e., small non-coding RNAs) that are associated with advanced PCa. Using purified microRNAs from formalin-fixed paraffin-embedded (FFPE) metastatic tissues and corresponding serum-derived extracellular vesicles (EVs), the protocol describes how to prepare libraries with appropriate quality control for sequencing microRNAs from these sample sources. Isolating RNA from both FFPE and EVs is often challenging because most of it is either degraded or is limited in quantity. This protocol will elaborate on different methods to optimize the RNA inputs and cDNA libraries to yield most specific reads and high-quality data upon sequencing.

Therapy resistance often develops in patients with advanced prostate cancer, and in some cases, cancer progresses to a lethal subtype called neuroendocrine prostate cancer. Assessing the small non-coding RNA-mediated molecular changes that facilitate this transition would allow better disease stratification and identification of causal mechanisms that lead to development of neuroendocrine prostate cancer.

Ablation of androgen receptor (AR) signaling by androgen deprivation is the goal of the first line of therapy for prostate cancer that initially results ...

Expansion and Enrichment of Gamma-Delta (&#947;&#948;) T Cells from Apheresed Human Product

Although V&#947;9V&#948;2 T cells are a minor subset of T lymphocytes, this population is sought after for its ability to recognize antigens in a major histocompatibility complex (MHC)-independent manner and develop strong cytolytic effector function that makes it an ideal candidate for cancer immunotherapy. Due to the low frequency of Gamma-Delta (&#947;&#948;) T cells in the peripheral blood, we developed an effective protocol to greatly expand a highly pure &#947;&#948; T cells drug product for first-in-human use of allogeneic &#947;&#948; T cells in patients with acute myeloid leukemia (AML). Using healthy donor apheresis as an allogenic cell source, the lymphocytes are isolated using a validated device for a counterflow centrifugation method of separating cells by size and density. 
The lymphocyte-rich fraction is utilized, and the &#947;&#948; T cells are preferentially activated with zoledronic acid (FDA-approved) and interleukin (IL)-2 for 7 days. Following the preferential expansion of &#947;&#948; T cells, a clinical-grade magnetic cell-separation device and TCR&#945;&#946; beads are used to deplete contaminating T-cell receptor (TCR)&#945;&#946; T cells. The highly enriched &#947;&#948; T cells then undergo a second expansion using engineered artificial antigen-presenting cells (aAPCs) derived from K562 cells-genetically engineered to express single-chain variable fragment (scFv) for CD3 and CD28, 41BBL (CD137L) and IL15-RA-together with zoledronic acid and IL-2. Seeding all day-7 enriched &#947;&#948; T cells in co-culture with the aAPCs facilitates the manufacture of highly pure &#947;&#948; T cells with an average fold expansion of &gt;229,000-fold from healthy donor blood.

Expansion and Enrichment of Gamma-Delta &#947;&#948; T Cells from Apheresed Human Product

Presented is a protocol for the expansion of Gamma-Delta (&#947;&#948;) T cell drug product. Lymphocytes are isolated by elutriation and &#947;&#948;-enriched with zoledronic acid and interleukin-2. Alpha-beta T cells are depleted using a clinical-grade magnetic separation device. The &#947;&#948; cells are co-cultured with K562-derived, artificial antigen-presenting cells and expanded.

Although V&#947;9V&#948;2 T cells are a minor subset of T lymphocytes, this population is sought after for its ability to recognize antigens in a major ...

In Vivo Immunogenicity Screening of Tumor-Derived Extracellular Vesicles by Flow Cytometry of Splenic T Cells

Immunogenic cell death of tumors, caused by chemotherapy or irradiation, can trigger tumor-specific T cell responses by releasing danger-associated molecular patterns and inducing the production of type I interferon. Immunotherapies, including checkpoint inhibition, primarily rely on preexisting tumor-specific T cells to unfold a therapeutic effect. Thus, synergistic therapeutic approaches that exploit immunogenic cell death as an intrinsic anti-cancer vaccine may improve their responsiveness. However, the spectrum of immunogenic factors released by cells under therapy-induced stress remains incompletely characterized, especially regarding extracellular vesicles (EVs). EVs, nano-scale membranous particles emitted from virtually all cells, are considered to facilitate intercellular communication and, in cancer, have been shown to mediate cross-priming against tumor antigens. To assess the immunogenic effect of EVs derived from tumors under various conditions, adaptable, scalable, and valid methods are sought-for. Therefore, herein a relatively easy and robust approach is presented to assess EVs' in vivo immunogenicity. The protocol is based on flow cytometry analysis of splenic T cells after in vivo immunization of mice with EVs, isolated by precipitation-based assays from tumor cell cultures under therapy or steady-state conditions. For example, this work shows that oxaliplatin exposure of B16-OVA murine melanoma cells resulted in the release of immunogenic EVs that can mediate the activation of tumor-reactive cytotoxic T cells. Hence, screening of EVs via in vivo immunization and flow cytometry identifies conditions under which immunogenic EVs can emerge. Identifying conditions of immunogenic EV release provides an essential prerequisite to testing EVs' therapeutic efficacy against cancer and exploring the underlying molecular mechanisms to ultimately unveil new insights into EVs' role in cancer immunology.

In Vivo Immunogenicity Screening of Tumor-Derived Extracellular Vesicles by Flow Cytometry of Splenic T Cells

This manuscript describes how to assess in vivo immunogenicity of tumor cell-derived extracellular vesicles (EVs) using flow cytometry. EVs derived from tumors undergoing treatment-induced immunogenic cell death seem particularly relevant in tumor immunosurveillance. This protocol exemplifies the assessment of oxaliplatin-induced immunostimulatory tumor EVs but can be adapted to various settings.

Immunogenic cell death of tumors, caused by chemotherapy or irradiation, can trigger tumor-specific T cell responses by releasing danger-associated ...

Generating and Imaging Mouse and Human Epithelial Organoids from Normal and Tumor Mammary Tissue Without Passaging

Organoids are a reliable method for modeling organ tissue due to their self-organizing properties and retention of function and architecture after propagation from primary tissue or stem cells. This method of organoid generation forgoes single-cell differentiation through multiple passages and instead uses differential centrifugation to isolate mammary epithelial organoids from mechanically and enzymatically dissociated tissues. This protocol provides a streamlined technique for rapidly producing small and large epithelial organoids from both mouse and human mammary tissue in addition to techniques for organoid embedding in collagen and basement extracellular matrix. Furthermore, instructions for in-gel fixation and immunofluorescent staining are provided for the purpose of visualizing organoid morphology and density. These methodologies are suitable for myriad downstream analyses, such as co-culturing with immune cells and ex vivo metastasis modeling via collagen invasion assay. These analyses serve to better elucidate cell-cell behavior and create a more complete understanding of interactions within the tumor microenvironment.

This protocol discusses an approach for generating epithelial organoids from primary normal and tumor mammary tissue through differential centrifugation. Furthermore, instructions are included for three-dimensional culturing as well as immunofluorescent imaging of embedded organoids.

Organoids are a reliable method for modeling organ tissue due to their self-organizing properties and retention of function and architecture after ...

Pancreatic Cancer-Derived Tumor Organoids and Fibroblasts from Fresh Tissue

Establishment of Pancreatic Cancer-Derived Tumor Organoids and Fibroblasts From Fresh Tissue

Tumor organoids are three-dimensional (3D) ex vivo tumor models that recapitulate the biological key features of the original primary tumor tissues. Patient-derived tumor organoids have been used in translational cancer research and can be applied to assess treatment sensitivity and resistance, cell-cell interactions, and tumor cell interactions with the tumor microenvironment. Tumor organoids are complex culture systems that require advanced cell culture techniques and culture media with specific growth factor cocktails and a biological basement membrane that mimics the extracellular environment. The ability to establish primary tumor cultures highly depends on the tissue of origin, the cellularity, and the clinical features of the tumor, such as the tumor grade. Furthermore, tissue sample collection, material quality and quantity, as well as correct biobanking and storage are crucial elements of this procedure. The technical capabilities of the laboratory are also crucial factors to consider. Here, we report a validated SOP/protocol that is technically and economically feasible for the culture of ex vivo tumor organoids from fresh tissue samples of pancreatic adenocarcinoma origin, either from fresh primary resected patient donor tissue or patient-derived xenografts (PDX). The technique described herein can be performed in laboratories with basic tissue culture and mouse facilities and is tailored for wide application in the translational oncology field.

Author Spotlight: Establishment of Pancreatic Cancer-Derived Tumor Organoids and Fibroblasts From Fresh Tissue  

Tumor organoids have revolutionized cancer research and the approach to personalized medicine. They represent a clinically relevant tumor model that allows researchers to stay one step ahead of the tumor in the clinic. This protocol establishes tumor organoids from fresh pancreatic tumor tissue samples and patient-derived xenografts of pancreatic adenocarcinoma origin.

Tumor organoids are three-dimensional (3D) ex vivo tumor models that recapitulate the biological key features of the original primary tumor tissues. ...