Name: digital analysis of immunostaining of zw10 interacting protein in human lung tissues
Uploaded: 2019-05-01T13:00:00
Description: Watch this Scientific Journal Video about Digital Analysis of Immunostaining of ZW10 Interacting Protein in Human Lung Tissues at JoVE.com

This project was supported by the National Natural Foundation of China (No. 81500151, 81400121, 81270607, 81541027, and 81501352) and the Natural Foundation of Hubei Province (China) (No. 2017CFB631). The authors express their appreciation to Guo Qin, Chang Min, Li Hui, and their colleagues at Wuhan Google Biological Technology Co., LTD for their technical support. The authors also thank Muhammad Jamal for the language editing.

All methods described here have been approved by the Ethical Committee of Zhongnan Hospital of Wuhan University and Renmin Hospital of Wuhan University.
1. Preparation of IHC Slides
<ol>
	<li>Fix the lung tissue sample by immersing the human lung tissue fragment (about 3 x 3 cm) in 4% paraformaldehyde in phosphate-buffered saline (PBS) for 24 h at room temperature (RT).</li>
	<li>Dehydrate the tissue in 80%, 95%, and 100% ethanol for 15 min, 20 min, and 20 min, respectively, at room temperat...

<ol>
	<li>Endo, H., Ikeda, K., Urano, T., Horie-Inoue, K., Inoue, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Terf/TRIM17+stimulates+degradation+of+kinetochore+protein+ZWINT+and+regulates+cell+proliferation.">Terf/TRIM17 stimulates degradation of kinetochore protein ZWINT and regulates cell proliferation.</a> The Journal of Biochemistry. 151 (2), 139-144 (2012).</li><li>Wang, 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=Human+Zwint-1+specifies+localization+of+Zeste+White+10+to+kinetochores+and+is+essential+for+mitotic+checkpoint+signaling.">Human Zwint-1 specifies localization of Zeste White 10 to kinetochores and is essential for mitotic checkpoint signaling.</a> Journal of Biological Chemistry. 279 (52), 54590-54598 (2004).</li><li>Lin, Y. T., Chen, Y., Wu, G., Lee, W. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hec1+sequentially+recruits+Zwint-1+and+ZW10+to+kinetochores+for+faithful+chromosome+segregation+and+spindle+checkpoint+control.">Hec1 sequentially recruits Zwint-1 and ZW10 to kinetochores for faithful chromosome segregation and spindle checkpoint control.</a> Oncogene. 25 (52), 6901-6914 (2006).</li><li>Ying, 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=Overexpression+of+Zwint+predicts+poor+prognosis+and+promotes+the+proliferation+of+hepatocellular+carcinoma+by+regulating+cell-cycle-related+proteins.">Overexpression of Zwint predicts poor prognosis and promotes the proliferation of hepatocellular carcinoma by regulating cell-cycle-related proteins.</a> OncoTargets and Therapy. 11, 689-702 (2018).</li><li>Yuan, W., 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=Bioinformatic+analysis+of+prognostic+value+of+ZW10+interacting+protein+in+lung+cancer.">Bioinformatic analysis of prognostic value of ZW10 interacting protein in lung cancer.</a> OncoTargets and Therapy. 11, 1683-1695 (2018).</li><li>Higgins, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Applications+and+challenges+of+digital+pathology+and+whole+slide+imaging.">Applications and challenges of digital pathology and whole slide imaging.</a> Biotechnic &amp; Histochemistry. 90 (5), 341-347 (2015).</li><li>Webster, J. D., Dunstan, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-slide+imaging+and+automated+image+analysis:+considerations+and+opportunities+in+the+practice+of+pathology.">Whole-slide imaging and automated image analysis: considerations and opportunities in the practice of pathology.</a> Veterinary Pathology. 51 (1), 211-223 (2014).</li><li>Al-Janabi, S., Huisman, A., van Diest, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+pathology:+current+status+and+future+perspectives.">Digital pathology: current status and future perspectives.</a> Histopathology. 61 (1), 1-9 (2012).</li><li>Bonomi, P. 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=Predictive+biomarkers+for+response+to+EGFR-directed+monoclonal+antibodies+for+advanced+squamous+cell+lung+cancer.">Predictive biomarkers for response to EGFR-directed monoclonal antibodies for advanced squamous cell lung cancer.</a> Annals of Oncology. 29 (8), 1701-1709 (2018).</li><li>Villalobos, 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=ERCC1+assessment+in+upfront+treatment+with+and+without+cisplatin-based+chemotherapy+in+stage+IIIB/IV+non-squamous+non-small+cell.">ERCC1 assessment in upfront treatment with and without cisplatin-based chemotherapy in stage IIIB/IV non-squamous non-small cell.</a> Medical Oncology. 35 (7), 106 (2018).</li><li>Griffin, J., Treanor, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+pathology+in+clinical+use:+where+are+we+now+and+what+is+holding+us+back?.">Digital pathology in clinical use: where are we now and what is holding us back?.</a> Histopathology. 70 (1), 134-145 (2017).</li><li>Huisman, A., Looijen, A., van den Brink, S. M., van Diest, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Creation+of+a+fully+digital+pathology+slide+archive+by+high-volume+tissue+slide+scanning.">Creation of a fully digital pathology slide archive by high-volume tissue slide scanning.</a> Human Pathology. 41 (5), 751-775 (2010).</li><li>Gray, A., Wright, A., Jackson, P., Hale, M., Treanor, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+histochemical+stains+using+whole+slide+imaging:+development+of+a+method+and+demonstration+of+its+usefulness+in+laboratory+quality+control.">Quantification of histochemical stains using whole slide imaging: development of a method and demonstration of its usefulness in laboratory quality control.</a> Journal of Clinical Pathology. 68 (3), 192-199 (2015).</li><li>Hofman, F. M., Taylor, C. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunohistochemistry.">Immunohistochemistry.</a> Current Protocols in Immunology. 103, (2013).</li><li>Ramos-Vara, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Principles+and+Methods+of+Immunohistochemistry.">Principles and Methods of Immunohistochemistry.</a> Methods in Molecular Biology. 1641, 115-128 (2017).</li><li>Otali, D., Fredenburgh, J., Oelschlager, D. K., Grizzle, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+standard+tissue+as+a+control+for+histochemical+and+immunohistochemical+staining.">A standard tissue as a control for histochemical and immunohistochemical staining.</a> Biotechnic &amp; Histochemistry. 91 (5), 309-326 (2016).</li><li>Clarke, E. L., Treanor, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Colour+in+digital+pathology:+a+review.">Colour in digital pathology: a review.</a> Histopathology. 70 (2), 153-163 (2017).</li><li>Potts, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+pathology+in+drug+discovery+and+development:+multisite+integration.">Digital pathology in drug discovery and development: multisite integration.</a> Drug Discovery Today. 14 (19-20), 935-941 (2009).</li><li>Tabata, 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=Whole-slide+imaging+at+primary+pathological+diagnosis:+Validation+of+whole-slide+imaging-based+primary+pathological+diagnosis+at+twelve+Japanese+academic+institutes.">Whole-slide imaging at primary pathological diagnosis: Validation of whole-slide imaging-based primary pathological diagnosis at twelve Japanese academic institutes.</a> Pathology International. 67 (11), 547-554 (2017).</li><li>Saco, A., Bombi, J. A., Garcia, A., Ram&#237;rez, J., Ordi, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+Status+of+Whole-Slide+Imaging+in+Education.">Current Status of Whole-Slide Imaging in Education.</a> Pathobiology. 83 (2-3), 79-88 (2016).</li><li>Griffin, J., Treanor, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+pathology+in+clinical+use:+where+are+we+now+and+what+is+holding+us+back?.">Digital pathology in clinical use: where are we now and what is holding us back?.</a> Histopathology. 70 (1), 134-145 (2017).</li></ol>

Whole-slide scanning is becoming a hot topic for its robust scanning and production of high-quality images for clinical and research purposes11,12,13. Images can be produced by slide-scanning microscopes within minutes11,12,13. By applying this methodology, we obtained high-quality images for ZWINT IHC slides and compared the H-score be...

ZW10 interacting protein (ZWINT) is a necessary component of the kinetochore complex which is involved in the mitotic spindle checkpoint1,2,3. It has been reported that the depletion of ZWINT leads to aberrant premature chromosome segregation1,2,3. Recent studies have suggested that ZWINT is involved in the pathogenesis of multiple tumors by promoting the proliferation of tumor cells4,5. We previously reported the overexpression of ZWINT in lung cancer5. It has been widely accepted that the analysis of slides by pathologists using CLM is time-consuming and not quantitative6,7,8. Moreover, the deterioration of stored glass slides might make it impossible to retract previously created slides. The emerging method of computer-based, digital whole-slide imaging (WSI) may overcome these limitations6,7,8.
To this end, we describe a methodology of the immunostaining of ZWINT in human lung cancer tissues, coupled with whole-slide digital scanning and software-based image analysis. The main advantage of this methodology is the production of concordant results with CLM. This technology can be widely used in the areas of pathological scoring of hematoxylin-eosin staining (H&#38;E) and IHC, fluorescence in situ hybridization (FISH), tissue microarrays (TMA), and drug discovery and development.

<table>
	<tbody>
		<tr>
			<td>Pannoramic MIDI</td>
			<td>3D HISTECH</td>
			<td>Cat: PMIDI-040709</td>
			<td>An automated digital slide scanner with a remarkable feature set :12-slide capacity, fluorescence scanning, and many more.</td>
		</tr>
		<tr>
			<td>QuantCenter</td>
			<td>3D HISTECH</td>
			<td>Downloaded from the official website of the company</td>
			<td>The framework for 3DHISTCH&#39;s image analysis applications.</td>
		</tr>
		<tr>
			<td>LEICA RM2235</td>
			<td>Leica Microsystems</td>
			<td>Cat: 14050038604</td>
			<td>The enhanced precision of the new accessories will add convenience to block to knife approach as well as specimen orientation.</td>
		</tr>
		<tr>
			<td>Rabbit anti-human Anti-ZWINT antibody</td>
			<td>Abcam</td>
			<td>Cat: ab197794</td>
			<td>Immunohistochemical analysis of ZWINT in human lung tissue.</td>
		</tr>
		<tr>
			<td>Anti-rabbit secondary antibody</td>
			<td>Wuhan Goodbio Technology</td>
			<td>Cat:GB23303-1</td>
			<td>Secondary antibody for IHC staining.</td>
		</tr>
		<tr>
			<td>Phosphate-buffered saline</td>
			<td>Wuhan Goodbio Technology</td>
			<td>Cat:G0002</td>
			<td>A solution containing a phosphate buffer.</td>
		</tr>
		<tr>
			<td>OLYMPUS CX23</td>
			<td>OLYMPUS</td>
			<td>Cat:6M87620</td>
			<td>Microscope for detection of H&#38;E or IHC slides.</td>
		</tr>
		<tr>
			<td>Dimethylbenzene</td>
			<td>Shanghai Lingfeng Chemical Reagent</td>
			<td>Cat:1330-20-7</td>
			<td>A colorless, flammable fluid used as a solvent and clarifying agent in the preparation of tissue sections for microscopic study.</td>
		</tr>
		<tr>
			<td>Hematoxylin Staining Solution</td>
			<td>Wuhan Servicebio technology</td>
			<td>Cat:G1039</td>
			<td>It is commonly used for histologic studies, oftern colors the nuclei of cells blue.</td>
		</tr>
		<tr>
			<td>Tween 20</td>
			<td>Baitg</td>
			<td>Cat:2005-64-5</td>
			<td>It is a polysorbate-type nonionic surfactant formed by the ethoxylation of sorbitan before the addition of lauric acid. It is used as a deterent and emulsifier in pharmacological applications.</td>
		</tr>
		<tr>
			<td>Citric acid repair liquid</td>
			<td>Wuhan Servicebio technology</td>
			<td>Cat:G1202</td>
			<td>Is is used to repair antigen after fixation during IHC procedure.</td>
		</tr>
		<tr>
			<td>LEICA ASP200s</td>
			<td>Leica</td>
			<td>Cat: 14048043626</td>
			<td>It was designed for routine and research histopathology of up to 200 cassettes.</td>
		</tr>
		<tr>
			<td>LEICA Arcadia H</td>
			<td>Leica</td>
			<td>Cat: 14039354103</td>
			<td>It is a heated paraffin embedding station and allows for simple operation and precise control, resulting in improved quality, a smooth workflow and reliability.</td>
		</tr>
		<tr>
			<td>LEICA Arcadia C</td>
			<td>Leica</td>
			<td>Cat: 14039354102</td>
			<td>It is a cold plate holding more than 60/65 cassettes on its large working surface. It was designed with an environment adaptive control module to make sure the operating temperature is always stabilized at -6&#176;C.</td>
		</tr>
		<tr>
			<td>CaseViewer Software</td>
			<td>3DHISTECH</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

digital analysis of immunostaining of zw10 interacting protein in human lung tissues

The purpose of this study is to introduce a methodology of the immunostaining of human lung tissues, followed by whole-slide digital scanning and image analysis. Digital scanning is a fast way to scan a stack of slides and produce digital images with high quality. It can produce concordant results with conventional light microscopy (CLM) by pathologists. Furthermore, the availability of digital images makes it possible that the same slide can be concurrently observed by multiple people. Moreover, digital images of slides can be stored in a database, which means the long-term deterioration of glass slides is avoided. The limitations of this technique are as follows. First, it needs high-quality prepared tissue and the original immunohistochemistry (IHC) slides without any damage or excess sealant residue. Second, tumor or nontumor areas should be specified by experienced pathologists before the analysis using software, in order to avoid any confusion about the tumor or nontumor areas during scoring. Third, the operator needs to control the color reproduction throughout the digitization process in whole-slide imaging.

We measured the expression levels of ZWINT in 28 pairs of non-small-cell lung cancer (NSCLC) specimens (tumor and adjacent nontumor tissues), including 14 squamous cell carcinomas(SCCs) and 14 adenocarcinomas (ADCs), by IHC. The whole-slide digital scanning of the slides provided digital images of high quality (Figure 1A). The results showed that the H-score of the lung cancer was significantly higher than that of adjacent noncancer tissues (P &#60; ...

Watch this Scientific Journal Video about Digital Analysis of Immunostaining of ZW10 Interacting Protein in Human Lung Tissues at JoVE.com

Digital Analysis of Immunostaining of ZW10 Interacting Protein in Human Lung Tissues

ZW10 interacting protein (ZWINT) participates in the mitotic spindle checkpoint and the pathogenesis of carcinoma. Here, we introduce a methodology of the immunostaining of ZWINT in human lung cancer tissues, followed by the digital scanning of whole slides and image analysis. This methodology can provide high-quality digital images and reliable results.

The purpose of this study is to introduce a methodology of the immunostaining of human lung tissues, followed by whole-slide digital scanning and image ...

This method can help answer key questions in the pathological and the immunohistochemistry. The main advantage of this technique is that faster enough and that produces digital media with high quality. Begin by fixing a three-by-three centimeter kung tissue sample in 4%paraformaldehyde for 24 hours at room temperature.The next day, dehydrate the tissue in ascending ethanol immersions at room temperature, followed by three immersions in 100%xylene for 20 minutes per treatment. After the last xylene immersion, place the tissue in 63-degree Celsius paraffin for 30 minutes, followed by a second 45-minute immersion in fresh 63-degree Celsius paraffin, then change the paraffin one more time for a final one-hour incubation. When the paraffin has cooled, use a rotary microtome to acquire five micrometer-thick sections of the paraffin-embedded tissue sample, capturing the sections on 20 microgram-per-milliliter poly-L-lysine-coated slides.For dewaxing, place the slides in a 65-degree Celsius oven for two hours, followed by immersion in dimethylbenzene for 15 minutes and soaking in 100%xylene for 15 minutes, then rehydrating the slides in a descending ethanol immersion series. For antigen repair, place the slides in an antigen-repair box and add 300 milliliters of citric acid repair liquid to the box. Heat the box in a microwave oven at high power for two minutes, followed by heating at low power to sustain boiling for six minutes.When the slides have cooled to room temperature, wash the tissue samples with three five-minute 0.01 molar PBS washes in a rotary shaker at room temperature. To eliminate the endogenous peroxidase, incubate the slides with 3%hydrogen peroxide in double-distilled water for 30 minutes in a wet box at room temperature. At the end of the incubation, wash the slides as demonstrated and plug any nonspecific binding on each section with 100 microliters of 10%goat serum for 39 minutes at 37 degrees Celsius.Next, label the tissues with 100 microliters of anti-ZWINT antibody per slide at four degrees Celsius overnight, followed by three washes in 0.01 molar PBS. After the last wash, incubate the slides with an appropriate secondary antibody for 30 minutes at 37 degrees Celsius, followed by three 0.01 molar PBS washes. After the last wash, add the slides to 300 microliters of fresh DAB for 10 minutes, followed by a 10-second wash with tap water at room temperature.Counters stain the tissues with hematoxylin staining solution for two minutes at room temperature, followed by washing in tap water for 15 minutes, then dehydrate the tissue again in ascending ethanol immersions, followed by two 15-minute immersions in xylene at room temperature. After the last 100%ethanol immersion, mount the sections with 15 microliters of a 5%xylene in neutral gum solution and cover each tissue sample with a cover glass. For automatic whole-slide scanning of the sections, first allow the slides to dry at room temperature for 12 hours to desiccate the tissue samples.Next, in the automatic whole-slide scanner, select Brightfield manually and enter the manual scanning interface. Revise the name of the slides and select a storage path for the images. Set the scanning area and select the scan samples using User-Set Thresholds option.The threshold is about 50 with a scanning-area expansion value of 200 micrometers. Set the scanning focus value and select Automatic Focus and Single Layer mode, then load the slides onto the work station and start the automatic scanning. When all of the slides have been scanned, save the images for later analysis.To analyze the images of the lung tissue sections, open the histopathological image-analysis software and select Local Computer to open the file with the scanning data. Select the appropriate zoom level and use Toggle Color Adjust to set the color to the optimal contrast, then circle and name the regions of interest on each image. Next, under plugins, select QC.The Scenario Builder will pop up.Select Density Quant and adjust the detection bar. Adjust the score levels until the staining intensity of the circled areas is similar to that of the original images, and store and name the model as a new file, then apply the model to other slides and select Selected Annotation to let the software automatically calculate the APE score for the regions of interest in each image. Whole-slide digital scanning of lung tissue sections of tumor and adjacent non-tumor tissues from non-small cell lung cancer specimens produces digital images of a high quality.APE scores calculated from these types of lung cancer samples are typically significantly higher than those determined for the adjacent non-cancer tissues. In addition, ZWINT expression levels in squamous-cell carcinoma tissue sections are frequently determined to be significantly higher than those measured in abnocarcinoma tissue samples. While attempting this procedure, it's important to remember to prepare with high quality of the tumor or tumor areas during making pathological scanning.Following this procedure, other methods of the microscopy can be performed in order to answer additional questions. Neither the or different method for pathological scanning. After this technique paved the way for researchers in the field of pathological scanning to explore digital diagnostics in the research purpose.Don't forget that working with paraformaldehyde can be extremely hazardous and precautions such as masks should always be taken while performing this procedure.

digital-analysis-immunostaining-zw10-interacting-protein-human-lung

Research

JoVE Journal

Cancer Research

Ex Vivo Imaging of Resident CD8 T Lymphocytes in Human Lung Tumor Slices Using Confocal Microscopy

CD8 T cell are key players in the fight against cancer. In order for CD8 T cells to kill tumor cells they need to enter into the tumor, migrate within the tumor microenvironment and respond adequately to tumor antigens. The recent development of improved imaging approaches, such as 2-photon microscopy, and the use of powerful mouse tumor models have shed light on some of the mechanisms that regulate anti-tumor T cell activities. Whereas such systems have provided valuable insights, they do not always predict human responses. In human, our knowledge in the field mainly comes from a description of fixed tumor samples from human patients, as well as in vitro studies. However, in vitro models lack the complex three-dimensional tumor milieu and, therefore, are incomplete approximations of in vivo T cell activities. Fresh slices made from explanted tissue represent a complex multi-cellular tumor environment that can act as an important link between co-cultured studies and animal models. Originally set up in murine lymph nodes1 and previously described in a JoVE article2, this approach has now been transposed to human tumors to examine the dynamics of both plated3&#160;as well as resident&#160;T cells4.
Here, a protocol for the preparation of human lung tumor slices, immunostaining of resident CD8 T and tumor cells, and tracking of CD8 T lymphocytes within the tumor microenvironment using confocal microscopy is described. This system is uniquely placed to screen for novel immunotherapy agents favoring T cell migration in tumors.

Ex Vivo Imaging of Resident CD8 T Lymphocytes in Human Lung Tumor Slices Using Confocal Microscopy

This protocol describes a method to image resident tumor-infiltrating CD8 T cells labeled with fluorescently coupled antibodies within human lung tumor slices. This technique permits real-time analyses of CD8 T cell migration using confocal microscopy.

CD8 T cell are key players in the fight against cancer. In order for CD8 T cells to kill tumor cells they need to enter into the tumor, migrate within the ...

The Establishment of a Lung Colonization Assay for Circulating Tumor Cell Visualization in Lung Tissues

Metastasis is the major cause of cancer death. The role of circulating tumor cells (CTCs) in promoting cancer metastasis, in which lung colonization by CTCs critically contributes to early lung metastatic processes, has been vigorously investigated. As such, animal models are the only approach that captures the full systemic process of metastasis. Given that problems occur in previous experimental designs for examining the contributions of CTCs to blood vessel extravasation, we established an in vivo lung colonization assay in which a long-term-fluorescence cell-tracer, carboxyfluorescein succinimidyl ester (CFSE), was used to label suspended tumor cells and lung perfusion was performed to clear non-specifically trapped CTCs prior to lung removal, confocal imaging, and quantification. Polymeric fibronectin (polyFN) assembled on CTC surfaces has been found to mediate lung colonization in the final establishment of metastatic tumor tissues. Here, to specifically test the requirement of polyFN assembly on CTCs for lung colonization and extravasation, we performed short term lung colonization assays in which suspended Lewis lung carcinoma cells (LLCs) stably expressing FN-shRNA (shFN) or scramble-shRNA (shScr) and pre-labeled with 20 &#956;M of CFSE were intravenously inoculated into C57BL/6 mice. We successfully demonstrated that the abilities of shFN LLC cells to colonize the mouse lungs were significantly diminished in comparison to shScr LLC cells. Therefore, this short-term methodology may be widely applied to specifically demonstrate the ability of CTCs within the circulation to colonize the lungs.

An animal model is needed to decipher the role of circulating tumor cells (CTCs) in promoting lung colonization during cancer metastasis. Here, we established and successfully performed an in vivo assay to specifically test the requirement of polymeric fibronectin (polyFN) assembly on CTCs for lung colonization.

Metastasis is the major cause of cancer death. The role of circulating tumor cells (CTCs) in promoting cancer metastasis, in which lung colonization by ...

Detection of a CDH1 Rare Transcript Variant in Fresh-frozen Gastric Cancer Tissues by Chip-based Digital PCR

CDH1a, a non-canonical transcript of the CDH1 gene, has been found to be expressed in some gastric cancer (GC) cell lines, whereas it is absent in normal gastric mucosa. Recently, we detected CDH1a transcript variant in fresh-frozen tumor tissues obtained from patients with GC. The expression of this variant in tissue samples was investigated by the chip-based digital PCR (dPCR) approach presented here. dPCR offers the potential for an accurate, robust, and highly sensitive measurement of nucleic acids and is increasingly utilized for many applications in different fields. dPCR is capable of detecting rare targets; in addition, dPCR offers the possibility for absolute and precise quantification of nucleic acids without the need for calibrators and standard curves. In fact, the reaction partitioning enriches the target from the background, which improves amplification efficiency and tolerance to inhibitors. Such characteristics make dPCR an optimal tool for the detection of the CDH1a rare transcript.

Detection of a CDH1 Rare Transcript Variant in Fresh-frozen Gastric Cancer Tissues by Chip-based Digital PCR

The manuscript describes a chip-based digital PCR assay to detect a rare CDH1 transcript variant (CDH1a) in fresh-frozen normal and tumor tissues obtained from patients with gastric cancer.

CDH1a, a non-canonical transcript of the CDH1 gene, has been found to be expressed in some gastric cancer (GC) cell lines, whereas it is absent in normal ...

Desthiobiotin-Streptavidin-Affinity Mediated Purification of RNA-Interacting Proteins in Mesothelioma Cells

The in vitro RNA-pulldown is still largely used in the first steps of protocols aimed at identifying RNA-binding proteins that recognize specific RNA structures and motifs. In this RNA-pulldown protocol, commercially synthesized RNA probes are labeled with a modified form of biotin, desthiobiotin, at the 3' terminus of the RNA strand, which reversibly binds to streptavidin and thus allows elution of proteins under more physiological conditions. The RNA-desthiobiotin is immobilized through interaction with streptavidin on magnetic beads, which are used to pull down proteins that specifically interact with the RNA of interest. Non-denatured and active proteins from the cytosolic fraction of mesothelioma cells are used as the source of proteins. The method described here can be applied to detect the interaction between known RNA binding proteins and a 25-nucleotide (nt) long RNA probe containing a sequence of interest. This is useful to complete the functional characterization of stabilizing or destabilizing elements present in RNA molecules achieved using a reporter vector assay.

Desthiobiotin labeling of a synthetic 25-nucleotide RNA oligo, which contains an adenine-rich element (ARE) motif, allows specific binding of cytosolic ARE-binding protein.

The in vitro RNA-pulldown is still largely used in the first steps of protocols aimed at identifying RNA-binding proteins that recognize specific RNA ...

Elastic Staining on Paraffin-embedded Slides of pT3N0M0 Gastric Cancer Tissue

The elastic lamina, which is usually located in the sub-mesothelial layer, adjacent to the peritoneum mesothelial cells, is amphiphilic on hematoxylin and eosin (H&amp;E) staining but can be visualized through elastic staining. One of the important benefits of elastic staining is that it makes it easy to determine whether tumor cells have invaded beyond the elastic lamina. This helps in examining the extent of peritoneal surface invasion, thereby distinguishing the pT3 and pT4 stages in gastrointestinal cancer. In this study, we present a protocol to identify elastic fibers in the formalin-fixed, paraffin-embedded pT3N0M0 gastric cancer tissue sections. We prepare 5-&#181;m paraffin sections fixed on slides, and then all the slides are deparaffinated and rehydrated during the staining procedure. Subsequently, all the sections are oxidized by potassium permanganate, bleached by oxalic acid, stained by elastic staining, and counterstained by Van Gieson's. Finally, we examine the effect of staining; elastic lamina is stained blue-black and collagen fibers are stained red, while the cancer cells are stained in varying shades of yellow. We also describe in detail the methods used for determining the positional relationship between cancer cells and elastic lamina. This method is simple, low-cost, and widely applicable in the identification of peritoneal surface invasion in gastrointestinal cancer because of its outstanding selectivity for elastic fibers and authentic results.

Here, we present a protocol of elastic staining to identify elastic fibers in pT3N0M0 gastric cancer tissues on formalin-fixed, paraffin-embedded sections. Subsequently, we describe a method to determine whether tumor cells invade beyond the elastic lamina.

The elastic lamina, which is usually located in the sub-mesothelial layer, adjacent to the peritoneum mesothelial cells, is amphiphilic on hematoxylin and ...

Droplet Digital TRAP (ddTRAP): Adaptation of the Telomere Repeat Amplification Protocol to Droplet Digital Polymerase Chain Reaction

The telomere repeat amplification protocol (TRAP) is the most widely used assay to detect telomerase activity within a given a sample. The polymerase chain reaction (PCR)-based method allows for robust measurements of enzyme activity from most cell lysates. The gel-based TRAP with fluorescently labeled primers limits sample throughput, and the ability to detect differences in samples is restricted to two fold or greater changes in enzyme activity. The droplet digital TRAP, ddTRAP, is a highly sensitive approach that has been modified from the traditional TRAP assay, enabling the user to perform a robust analysis on 96 samples per run and obtain absolute quantification of the DNA (telomerase extension products) input within each PCR. Therefore, the newly developed ddTRAP assay overcomes the limitations of the traditional gel-based TRAP assay and provides a more efficient, accurate, and quantitative approach to measuring telomerase activity within laboratory and clinical settings.

Droplet Digital TRAP ddTRAP: Adaptation of the Telomere Repeat Amplification Protocol to Droplet Digital Polymerase Chain Reaction

We successfully converted the standard telomere repeat amplification protocol (TRAP) assay to be employed in droplet digital polymerase chain reactions. This new assay, called ddTRAP, is more sensitive and quantitative, allowing for better detection and statistical analysis of telomerase activity within various human cells.

The telomere repeat amplification protocol (TRAP) is the most widely used assay to detect telomerase activity within a given a sample. The polymerase ...

Preparation of Mitochondria from Ovarian Cancer Tissues and Control Ovarian Tissues for Quantitative Proteomics Analysis

Ovarian cancer is a common gynecologic cancer with high mortality but unclear molecular mechanism. Most ovarian cancers are diagnosed in the advanced stage, which seriously hampers therapy. Mitochondrial changes are a hallmark of human ovarian cancers, and mitochondria are the centers of energy metabolism, cell signaling, and oxidative stress. In-depth insights into the changes of the mitochondrial proteome in ovarian cancers compared to control ovarian tissue will benefit in-depth understanding of the molecular mechanisms of ovarian cancer, and the discovery of effective and reliable biomarkers and therapeutic targets. An effective mitochondrial preparation method coupled with an isobaric tag for relative and absolute quantification (iTRAQ) quantitative proteomics are presented here to analyze human ovarian cancer and control mitochondrial proteomes, including differential-speed centrifugation, density gradient centrifugation, quality assessment of mitochondrial samples, protein digestion with trypsin, iTRAQ labeling, strong cation exchange fractionation (SCX), liquid chromatography (LC), tandem mass spectrometry (MS/MS), database analysis, and quantitative analysis of mitochondrial proteins. Many proteins have been successfully identified to maximize the coverage of the human ovarian cancer mitochondrial proteome and to achieve the differentially expressed mitochondrial protein profile in human ovarian cancers.

This article presents a protocol of differential-speed centrifugation in combination with density gradient centrifugation to separate mitochondria from human ovarian cancer tissues and control ovarian tissues for quantitative proteomics analysis, resulting in a high-quality mitochondrial sample and high-throughput and high-reproducibility quantitative proteomics analysis of a human ovarian cancer mitochondrial proteome.

Ovarian cancer is a common gynecologic cancer with high mortality but unclear molecular mechanism. Most ovarian cancers are diagnosed in the advanced ...

Pathological Analysis of Lung Metastasis Following Lateral Tail-Vein Injection of Tumor Cells

Metastasis, the primary cause of morbidity and mortality for most cancer patients, can be challenging to model preclinically in mice. Few spontaneous metastasis models are available. Thus, the experimental metastasis model involving tail-vein injection of suitable cell lines is a mainstay of metastasis research. When cancer cells are injected into the lateral tail-vein, the lung is their preferred site of colonization. A potential limitation of this technique is the accurate quantification of the metastatic lung tumor burden. While some investigators count macrometastases of a pre-defined size and/or include micrometastases following sectioning of tissue, others determine the area of metastatic lesions relative to normal tissue area. Both of these quantification methods can be exceedingly difficult when the metastatic burden is high. Herein, we demonstrate an intravenous injection model of lung metastasis followed by an advanced method for quantifying metastatic tumor burden using image analysis software. This process allows for investigation of multiple end-point parameters, including average metastasis size, total number of metastases, and total metastasis area, to provide a comprehensive analysis. Furthermore, this method has been reviewed by a veterinary pathologist board-certified by the American College of Veterinary Pathologists (SEK) to ensure accuracy.

Intravenous injection of cancer cells is often used in metastasis research, but the metastatic tumor burden can be difficult to analyze. Herein, we demonstrate a tail-vein injection model of metastasis and include a novel approach to analyze the resulting metastatic lung tumor burden.

Metastasis, the primary cause of morbidity and mortality for most cancer patients, can be challenging to model preclinically in mice. Few spontaneous ...

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 ...

In Vitro Evaluation of Oncogenic Transformation in Human Mammary Epithelial Cells

Tumorigenesis is a multi-step process in which cells acquire capabilities&#160;that allow their growth, survival, and dissemination under hostile conditions. Different tests seek to identify and quantify these hallmarks of cancerous cells; however, they often focus on a single aspect of cellular transformation and, in fact, multiple tests are required for their proper characterization. The purpose of this work is to provide researchers with a set of tools to assess cellular transformation in vitro from a broad perspective, thereby making it possible to draw sound conclusions.
A sustained proliferative signaling activation is the major feature of tumoral tissues and can be easily monitored under in vitro conditions by calculating the number of population doublings achieved over time. Besides, the growth of cells in 3D cultures allows their interaction with surrounding cells, resembling what occurs in vivo. This enables the evaluation of cellular aggregation and, together with immunofluorescent labeling of distinctive cellular markers, to obtain information on another relevant feature of tumoral transformation: the loss of proper organization. Another remarkable characteristic of transformed cells is their capacity to grow without attachment to other cells and to the extracellular matrix, which can be evaluated with the anchorage assay.
Detailed experimental procedures to evaluate cell growth rate, to perform immunofluorescent labeling of cell lineage markers in 3D cultures, and to test anchorage-independent cell growth in soft agar are provided. These methodologies are optimized for Breast Primary Epithelial Cells (BPEC) due to its relevance in breast cancer; however, procedures can be applied to other cell types after some adjustments.

This protocol provides experimental in vitro tools to evaluate the transformation of human mammary cells. Detailed steps to follow-up cell proliferation rate, anchorage-independent growth capacity, and distribution of cell lineages in 3D cultures with basement membrane matrix are described.