Name: detection of a circulating microrna custom panel in patients with metastatic colorectal cancer
Uploaded: 2019-03-14T13:00:00
Description: Watch this Scientific Journal Video about Detection of a Circulating MicroRNA Custom Panel in Patients with Metastatic Colorectal Cancer at JoVE.com

This study was partially funded by Roche S.p.A. and the Italian Medicines Agency (AIFA).

NOTE: Perform all of the following steps under a sterilized fume hood according to Good Laboratory Practice (GLP).
1. Plasma Collection and Storage
<ol>
	<li>Collect 3 mL of peripheral blood sample in a K3E EDTA tube.</li>
	<li>Centrifuge the tube at room temperature at 1,880 x g for 15 min.</li>
	<li>Recover the supernatant plasma in aliquots of 450 &#181;L.</li>
	<li>Store the samples at -80 &#176;C until use. 
	NOTE: Process the peripheral b...

<ol>
	<li>Luo, H. -. Y., Xu, R. -. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Predictive+and+prognostic+biomarkers+with+therapeutic+targets+in+advanced+colorectal+cancer.">Predictive and prognostic biomarkers with therapeutic targets in advanced colorectal cancer.</a> World journal of gastroenterology. 20 (14), 3858-3874 (2014).</li><li>Toiyama, Y., Okugawa, Y., Fleshman, J., Richard, C., Goel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MicroRNAs+as+potential+liquid+biopsy+biomarkers+in+colorectal+Cancer:+A+systematic+review.">MicroRNAs as potential liquid biopsy biomarkers in colorectal Cancer: A systematic review.</a> BBA Reviews on Cancer. 5 (6), (2018).</li><li>Kok, M. G. M., Halliani, A., Moerland, P. D., Meijers, J. C. M., Creemers, E. E., Pinto-Sietsma, 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=Normalization+panels+for+the+reliable+quantification+of+circulating+microRNAs+by+RT-qPCR.">Normalization panels for the reliable quantification of circulating microRNAs by RT-qPCR.</a> FASEB Journal. 29 (9), 3853-3862 (2015).</li><li>Marabita, F., De Candia, P., Torri, A., Tegn&#233;r, J., Abrignani, S., Rossi, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Normalization+of+circulating+microRNA+expression+data+obtained+by+quantitative+real-time+RT-PCR.">Normalization of circulating microRNA expression data obtained by quantitative real-time RT-PCR.</a> Briefings in Bioinformatics. 17 (2), 204-212 (2016).</li><li>Danese, 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=Reference+miRNAs+for+colorectal+cancer:+Analysis+and+verification+of+current+data.">Reference miRNAs for colorectal cancer: Analysis and verification of current data.</a> Scientific Reports. 7 (1), 1-12 (2017).</li><li>Zheng, G., 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=Identification+and+validation+of+reference+genes+for+qPCR+detection+of+serum+microRNAs+in+colorectal+adenocarcinoma+patients.">Identification and validation of reference genes for qPCR detection of serum microRNAs in colorectal adenocarcinoma patients.</a> PLoS ONE. 8 (12), 1-10 (2013).</li><li>Lv, 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=Optimization+of+the+Original+TRIzol-Based+Technique+Improves+the+Extraction+of+Circulating+MicroRNA+from+Serum+Samples.">Optimization of the Original TRIzol-Based Technique Improves the Extraction of Circulating MicroRNA from Serum Samples.</a> Clinical laboratory. 61 (12), 1953-1960 (2015).</li><li>Tan, G. W., Khoo, A. S. B., Tan, L. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+extraction+kits+and+RT-qPCR+systems+adapted+to+high-throughput+platform+for+circulating+miRNAs.">Evaluation of extraction kits and RT-qPCR systems adapted to high-throughput platform for circulating miRNAs.</a> Scientific reports. 5, 9430 (2015).</li><li>Altman, D. G., McShane, L. M., Sauerbrei, W., Taube, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reporting+Recommendations+for+Tumor+Marker+Prognostic+Studies+(REMARK):+explanation+and+elaboration.">Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK): explanation and elaboration.</a> PLoS medicine. 9 (5), (2012).</li><li>Tiberio, P., Callari, M., Angeloni, V., Daidone, M. G., Appierto, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Challenges+in+using+circulating+miRNAs+as+cancer+biomarkers.">Challenges in using circulating miRNAs as cancer biomarkers.</a> BioMed Research International. 2015, (2015).</li><li>Kroh, E. M., Parkin, R. K., Mitchell, P. S., Tewari, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+circulating+microRNA+biomarkers+in+plasma+and+serum+using+quantitative+reverse+transcription-PCR+(qRT-PCR).">Analysis of circulating microRNA biomarkers in plasma and serum using quantitative reverse transcription-PCR (qRT-PCR).</a> Methods (San Diego, Calif). 50 (4), 298-301 (2010).</li><li>Cheng, H. 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=Plasma+Processing+Conditions+Substantially+Influence+Circulating+microRNA+Biomarker+Levels.">Plasma Processing Conditions Substantially Influence Circulating microRNA Biomarker Levels.</a> PLoS ONE. 8 (6), 1-11 (2013).</li><li>Moret, 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=Assessing+an+improved+protocol+for+plasma+microRNA+extraction.">Assessing an improved protocol for plasma microRNA extraction.</a> PloS one. 8 (12), (2013).</li><li>Khoury, S., Ajuyah, P., Tran, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+small+noncoding+RNAs+from+human+serum).">Isolation of small noncoding RNAs from human serum).</a> Journal of visualized experiments JoVE. (88), e51443 (2014).</li><li>Schwarzenbach, H., Nishida, N., Calin, G. A., Pantel, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+relevance+of+circulating+cell-free+microRNAs+in+cancer.">Clinical relevance of circulating cell-free microRNAs in cancer.</a> Nature Reviews Clinical Oncology. 11 (3), 145-156 (2014).</li></ol>

miRNAs are small non-coding RNAs (18-25 nucleotides in length) capable of binding the 3&#39; UTR region of their target messenger RNA and inhibiting and/or degrading it. They can thus be considered gene expression regulators at the translational level. In the last decade, several miRNAs have been correlated with cancer initiation and development, making them useful clinical biomarkers for diagnosis, prognosis and therapy. Protected by RNases, miRNAs are present in a stable form in biological fluids such as blood, plasma,...

CRC represents the third most frequently diagnosed malignancy and the fourth cause of cancer-related death worldwide. To date, bevacizumab (B), a monoclonal antibody directed against vascular-endothelial growth factor (VEGF), and cetuximab (C) or panitumumab (P), monoclonal antibodies directed against epidermal growth factor receptor (EGFR), have been approved for first-line treatment in combination with chemotherapy (CT) regimens.
Mutations in K-RAS and N-RAS genes are the only clinically useful biomarkers capable of identifying patients who are least likely to benefit from anti-EGFR-based CT. Although several studies have been conducted to search for biomarkers that are predictive of response to B-based CT, there is still a substantial lack of reliable and effective drugs for use in clinical practice1.
miRNAs are small RNAs (18-25 nucleotides in length) that regulate the translation of target genes and play a crucial role in numerous physiopathological processes, including embryogenesis and carcinogenesis. These molecules are highly stable in biological fluids such as plasma/serum, urine and sputum, which renders them robust biomarkers to use for non-invasive sampling2. Using a panel of miRNAs involved in the angiogenic pathway, we aimed to identify new circulating biomarkers capable of predicting clinical outcome in patients with metastatic CRC (mCRC) treated with a B-based CT regimen.
We analyzed a series of 52 mCRC patients treated with B-based CT within the prospective multicenter randomized phase III trial &#34;Italian Trial in Advanced Colorectal Cancer&#34; (ITACa). The present protocol was approved by the Local Ethics Committee (Comitato Etico Area Vasta e Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, no. 674) on 19th September 2007. All patients gave informed consent before blood sample collection. For each patient, venous blood samples were collected before treatment and at the first clinical evaluation (after 8 weeks) to evaluate baseline miRNA expression and its modulation during treatment in relation to patient outcome.
Through a search of the literature, we selected 21 miRNAs correlated with the angiogenic process that are known to be detectable in human plasma: hsa-miR-107, hsa-miR-126-3p, hsa-miR-145-5p, hsa-miR-194-5p, hsa-miR-199a-5p, hsa-miR-200b-3p, hsa-miR-20b-5p, hsa-miR-21-5p, hsa-miR-210-3p, hsa-miR-221-3p, hsa-miR-24-3p, hsa-miR-27a-3p, hsa-miR-29b-3p, hsa-miR-335-5p, hsa-miR-424-5p, hsa-miR-497-5p, hsa-miR-520d-3p, hsa-miR-92a-3p, hsa-miR-17-5p and hsa-miR-155-5p. We also selected hsa-miR-223-3p and hsa-mir-484 for endogenous normalization3,4,5,6, and cel-miR-39 purified from C. elegans as a spike-in for exogenous normalization. All data normalizations were performed using the 2 &#770; &#772;(&#916;&#916;Ct) method.
The detection of circulating miRNAs presents some technical difficulties because the molecules are present at very low levels in plasma and their amplification is chemically challenging given their short sequence. For these reasons, we selected a procedure that considers both organic extraction with phenol and a glass-fiber column-based methodology. Circulating miRNA extraction is a hot topic in the field of liquid biopsy, and we selected a commercial kit that has shown to be one of the most reliable in terms of amount and quality of recovered yields7,8. We selected a protocol to reverse transcribe miRNAs by the addition of an adapter at 5&#39; and a poly(A) tail to 3&#39; of the mature miRNA to enhance the selectivity and specificity of the reaction.
Given the robustness of the method, we designed custom plates with pre-spotted probes for RT-PCR to assess each sample in duplicate and analyzed 2 patients within each plate, as shown in Figure 1.

<table>
	<tbody>
		<tr>
			<td>Rnase-free Safe-lock 1.5 mL tubes</td>
			<td>Eppendorf</td>
			<td>0030 123.328</td>
			<td></td>
		</tr>
		<tr>
			<td>Rnase-free Safe-lock 2 mL tubes</td>
			<td>Eppendorf</td>
			<td>0030 123.344</td>
			<td></td>
		</tr>
		<tr>
			<td>Rnase-free 20 &#181;L tips</td>
			<td>Starlab</td>
			<td>S1123-1810</td>
			<td></td>
		</tr>
		<tr>
			<td>Rnase-free 200 &#181;L tips</td>
			<td>Starlab</td>
			<td>S1120-8810</td>
			<td></td>
		</tr>
		<tr>
			<td>Rnase-free 1000 &#181;L tips</td>
			<td>Starlab</td>
			<td>S1122-1830</td>
			<td></td>
		</tr>
		<tr>
			<td>mirVana PARIS RNA and Native Protein Purification Kit</td>
			<td>Thermo Fisher</td>
			<td>AM1556</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan Advanced miRNA cDNA Synthesis Kit</td>
			<td>Thermo Fisher</td>
			<td>A28007</td>
			<td></td>
		</tr>
		<tr>
			<td>100% ethanol anidrous ACS grade</td>
			<td>Carlo Erba Reagents</td>
			<td>414605</td>
			<td></td>
		</tr>
		<tr>
			<td>2-mercapto-ethanol</td>
			<td>Sigma-Aldrich</td>
			<td>M3148</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan Fast Advanced Master Mix</td>
			<td>Thermo Fisher</td>
			<td>4444558</td>
			<td></td>
		</tr>
		<tr>
			<td>TaqMan Advanced miRNA Assays</td>
			<td>Thermo Fisher</td>
			<td>A25576</td>
			<td></td>
		</tr>
		<tr>
			<td>7500 Real-Time PCR System</td>
			<td>Applied Biosystems</td>
			<td>4406984</td>
			<td></td>
		</tr>
		<tr>
			<td>0.2-2, 1-10, 2-20, 20-200, 100-1000 &#181;L laboratory pipettes</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Benchtop microcentrifuge</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Vortex</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Benchtop heating block</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fume hood</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>0.2 mL PCR tubes</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

detection of a circulating microrna custom panel in patients with metastatic colorectal cancer

There is increasing interest in liquid biopsy for cancer diagnosis, prognosis and therapeutic monitoring, creating the need for reliable and useful biomarkers for clinical practice. Here, we present a protocol to extract, reverse transcribe and evaluate the expression levels of circulating miRNAs from plasma samples of patients with colorectal cancer (CRC). microRNAs (miRNAs) are a class of non-coding RNAs of 18-25 nucleotides in length that regulate the expression of target genes at the translational level and play an important role, including that of pro- and anti-angiogenic function, in the physiopathology of various organs. miRNAs are stable in biological fluids such as serum and plasma, which renders them ideal circulating biomarkers for cancer diagnosis, prognosis and treatment decision-making and monitoring. Circulating miRNA extraction was performed using a rapid and effective method that involves both organic and column-based methodologies. For miRNA retrotranscription, we used a multi-step procedure that considers polyadenylation at 3&#39; and the ligation of an adapter at 5&#39; of the mature miRNAs, followed by random miRNA pre-amplification. We selected a 24-miRNA custom panel to be tested by quantitative real-time polymerase chain reaction (qRT-PCR) and spotted the miRNA probes on array custom plates. We performed qRT-PCR plate runs on a real-time PCR System. Housekeeping miRNAs for normalization were selected using GeNorm software (v. 3.2). Data were analyzed using Expression suite software (v 1.1) and statistical analyses were performed. The method proved to be reliable and technically robust and could be useful to evaluate biomarker levels in liquid samples such as plasma and/or serum.

We analyzed a panel of angiogenesis-related circulating miRNAs in relation to progression-free survival (PFS), overall survival (OS) and objective response rate (ORR) in a 52 mCRC patients treated with B-based CT. The evaluation of such biomarkers in plasma samples is challenging because of technical difficulties. We used established methods for miRNA extraction from patient plasma samples, reverse transcription and pre-amplification. Following the manufacturer&#39;s instructions and with...

Watch this Scientific Journal Video about Detection of a Circulating MicroRNA Custom Panel in Patients with Metastatic Colorectal Cancer at JoVE.com

Detection of a Circulating MicroRNA Custom Panel in Patients with Metastatic Colorectal Cancer

We present a protocol to evaluate the expression levels of circulating microRNA (miRNAs) in plasma samples from cancer patients. In particular, we used a commercially available kit for circulating miRNA extraction and reverse transcription. Finally, we analyzed a panel of 24 selected miRNAs using real-time pre-spotted probe custom plates.

There is increasing interest in liquid biopsy for cancer diagnosis, prognosis and therapeutic monitoring, creating the need for reliable and useful ...

This method can help answer key questions in the translational research field, such as the relationship between circulating biomarkers and the patient prognosis. The main advantage of this technique is the chance to evaluate the expression of a panel of circulating biomarkers with an easy and reliable methodology with low amount of input material. The implications of this technique extend toward therapy of cancer patients because it could identify circulating biomarkers useful in decision-making and treatment monitoring of patients.Also, this method can provide insight into circulating biomarkers analysis. It can also be applied to other systems, such as tissue biomarker expression analysis for molecular characterization of disease. Visual demonstration of this method is critical, as the extraction steps are difficult to learn.To begin, transfer 400 microliters of the plasma sample into an RNase-free, two-milliliter tube. Then, add 400 microliters of denaturing solution to the tube. Add four microliters of one-nanomolar spike-in.After mixing the solution, add 800 microliters of acid phenol-chloroform. Vortex the solution for 60 seconds, and centrifuge at maximum speed for 15 minutes. Next, transfer the lysate contained in the upper aqueous phase to a clean tube, taking care not to disturb the interphase.Measure the volume of the aqueous phase recovered, and add 1/3 volume of ethanol to the lysate. Then, place a filter cartridge into a fresh collection tube. Transfer up to 700 microliters of the ethanol-lysate mixture to the filter cartridge.Centrifuge the filter cartridge for 30 seconds at 10, 000 times gravity. Next, measure the total volume of the flow-through. Then, add 2/3 of the volume of ethanol to the filtrate, and mix well.Place a second filter cartridge into a fresh collection tube. Then, transfer up to 700 microliters of the sample to the cartridge, and centrifuge at 10, 000 times gravity for 30 seconds before discarding the flow-through. Add 700 microliters of microRNA wash solution to the filter cartridge, and centrifuge it with a collection tube at 10, 000 times gravity for 15 seconds.Discard the flow-through, and put the filter cartridge back into the same tube. After this, move the filter cartridge to a new collection tube. Then, add 100 microliters of preheated elution solution to the cartridge.Centrifuge the filter cartridge at 10, 000 times gravity for 30 seconds to recover the microRNAs. Prepare the polyadenylation reaction mix cocktail according to the text protocol. Transfer two microliters of the sample to each well of a reaction plate.Then, add three microliters of the reaction cocktail to each well. Vortex and centrifuge the plate briefly to spin down the contents. Next, place the plate in a thermal cycler, and follow the procedure outlined in the text protocol.Prepare the ligation reaction mix cocktail in a centrifuge tube. Next, add 10 microliters of the cocktail to each well of the reaction plate. Then, mix the contents of the reaction plate on a shaker at 1, 900 rpm for one minute, followed by a brief centrifuge of the plate.After this, place the reaction plate in a thermal cycler, and follow the procedure outlined in the text protocol. To perform the reverse transcription reaction, prepare the reaction mix in a centrifuge tube according to the text protocol. Then, add 15 microliters of the mix to each well of the plate containing ligation product.Mix the contents of the plate on a shaker at 1, 900 rpm for one minute, followed by a brief centrifuge of the plate. Next, place the plate in a thermal cycler, and follow the procedure outlined in the text protocol. Then, prepare the miR-Amp reaction mix, and add 45 microliters of the mix to each well of a new reaction plate.After this, add five microliters of the RT product to each well of the reaction plate. Mix the plate on a shaker at 1, 900 rpm for one minute, followed by a brief centrifuge of the plate. Then, place the plate in a thermal cycler, and follow the procedure outlined in table one of the text protocol.First, dilute each cDNA sample in TE buffer. Then, prepare the PCR reaction mix in a centrifuge tube. adding 10%of the volume in excess.Transfer 19 microliters of the reaction mix to each well of the plate. Seal the plate, and centrifuge it briefly. Finally, perform the thermal protocol on an RT-PCR system, as outlined in table two of the text protocol.Serial dilutions of spike-in control were performed in order to choose which was the best concentration to add in all plasma samples of this particular case series. Thanks to this protocol, it was possible to evaluate all the biomarkers in every single patient, as well as a single biomarker in the overall case series. In this protocol, a panel of angiogenesis-related circulating miRNAs in relation to progression-free survival, overall survival, and objective response rate was analyzed in patients with colorectal cancer treated with a chemotherapy regimen.Comparing the expression levels of miRNA between baseline and first clinical evaluation, an increase in hsa-miR-155-5p was observed. This increase was associated with shorter PFS and OS.While attempting this procedure, it's important to remember to perform the steps using phenol-chloroform under a fume hood. Following this procedure, other methods like isolation and analysis of circulating proteins or coding RNAs can be performed in order to answer additional questions, like evaluation of a more exhaustive panel of circulating biomarkers.After its development, this technique paved the way for researchers in the field of liquid biopsy to explore the expression of circulating biomarkers in cancer patients. Don't forget that working with blood and chemical reagents can be extremely hazardous, and precautions such as gloves and laboratory coat should always be taken while performing this procedure.

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Research

JoVE Journal

Cancer Research

Advanced Animal Model of Colorectal Metastasis in Liver: Imaging Techniques and Properties of Metastatic Clones

Patients with a limited number of hepatic metastases and slow rates of progression can be successfully treated with local treatment approaches1,2. However, little is known about the heterogeneity of liver metastases, and animal models capable of evaluating the development of individual metastatic colonies are needed. Here, we present an advanced model of hepatic metastases that provides the ability to quantitatively visualize the development of individual tumor clones in the liver and estimate their growth kinetics and colonization efficiency. We generated a panel of monoclonal derivatives of HCT116 human colorectal cancer cells stably labeled with luciferase and tdTomato and possessing different growth properties. With a splenic injection followed by a splenectomy, the majority of these clones are able to generate hepatic metastases, but with different frequencies of colonization and varying growth rates. Using the In Vivo&#160;Imaging System (IVIS), it is possible to visualize and quantify metastasis development with in vivo luminescent and ex vivo fluorescent imaging. In addition, Diffuse Luminescent Imaging Tomography (DLIT) provides a 3D distribution of liver metastases in vivo. Ex vivo fluorescent imaging of harvested livers provides quantitative measurements of individual hepatic metastatic colonies, allowing for the evaluation of the frequency of liver colonization and the growth kinetics of metastases. Since the model is similar to clinically observed liver metastases, it can serve as a modality for detecting genes associated with liver metastasis and for testing potential ablative or adjuvant treatments for liver metastatic disease.

The ability of metastatic clones to colonize distant sites depends on their proliferation capacity and/or their ability to survive in the host microenvironment without significant proliferation. Here, we present an animal model that allows quantitative visualization of both types of liver colonization by metastatic clones.

Patients with a limited number of hepatic metastases and slow rates of progression can be successfully treated with local treatment approaches1,2. ...

A Syngeneic Mouse Model of Metastatic Renal Cell Carcinoma for Quantitative and Longitudinal Assessment of Preclinical Therapies

Renal cell carcinoma (RCC) affects &#62; 60,000 people in the United States annually, and ~ 30% of RCC patients have multiple metastases at the time of diagnosis. Metastatic RCC (mRCC) is incurable, with a median survival time of only 18 months. Immune-based interventions (e.g., interferon (IFN) and interleukin (IL)-2) induce durable responses in a fraction of mRCC patients, and multikinase inhibitors (e.g., sunitinib or sorafenib) or anti-VEGF receptor monoclonal antibodies (mAb) are largely palliative, as complete remissions are rare. Such shortcomings in current therapies for mRCC patients provide the rationale for the development of novel treatment protocols. A key component in the preclinical testing of new therapies for mRCC is a suitable animal model. Beneficial features that recapitulate the human condition include a primary renal tumor, renal tumor metastases, and an intact immune system to investigate any therapy-driven immune effector responses and the formation of tumor-induced immunosuppressive factors. This report describes an orthotopic mRCC mouse model that has all of these features. We describe an intrarenal implantation technique using the mouse renal adenocarcinoma cell line Renca, followed by the assessment of tumor growth in the kidney (primary site) and lungs (metastatic site).

Implementation of an orthotopic model of renal cell carcinoma in immunocompetent mice affords the investigator a clinically-relevant system defined by the presence of a primary renal tumor and lung metastases in the same animal. This system can be used to preclinically test a variety of treatments in vivo.

Renal cell carcinoma (RCC) affects &#62; 60,000 people in the United States annually, and ~ 30% of RCC patients have multiple metastases at the time of ...

Isolation of Circulating Tumor Cells in an Orthotopic Mouse Model of Colorectal Cancer

Despite the advantages of easy applicability and cost-effectiveness, subcutaneous mouse models have severe limitations and do not accurately simulate tumor biology and tumor cell dissemination. Orthotopic mouse models have been introduced to overcome these limitations; however, such models are technically demanding, especially in hollow organs such as the large bowel. In order to produce uniform tumors which reliably grow and metastasize, standardized techniques of tumor cell preparation and injection are critical. 
We have developed an orthotopic mouse model of colorectal cancer (CRC) which develops highly uniform tumors and can be used for tumor biology studies as well as therapeutic trials. Tumor cells from either primary tumors, 2-dimensional (2D) cell lines or 3-dimensional (3D) organoids are injected into the cecum and, depending on the metastatic potential of the injected tumor cells, form highly metastatic tumors. In addition, CTCs can be found regularly. We here describe the technique of tumor cell preparation from both 2D cell lines and 3D organoids as well as primary tumor tissue, the surgical and injection techniques as well as the isolation of CTCs from the tumor-bearing mice, and present tips for troubleshooting.

We describe the establishment of orthotopic colorectal tumors via injection of tumor cells or organoids into the cecum of mice and the subsequent isolation of circulating tumor cells (CTCs) from this model.

Despite the advantages of easy applicability and cost-effectiveness, subcutaneous mouse models have severe limitations and do not accurately simulate ...

A Genetically Engineered Mouse Model of Sporadic Colorectal Cancer

Despite the advantages of easy applicability and cost-effectiveness, colorectal cancer mouse models based on tumor cell injection have severe limitations and do not accurately simulate tumor biology and tumor cell dissemination. Genetically engineered mouse models have been introduced to overcome these limitations; however, such models are technically demanding, especially in large organs such as the colon in which only a single tumor is desired.
As a result, an immunocompetent, genetically engineered mouse model of colorectal cancer was developed which develops highly uniform tumors and can be used for tumor biology studies as well as therapeutic trials. Tumor development is initiated by surgical, segmental infection of the distal colon with adeno-cre virus in compound conditionally mutant mice. The tumors can be easily detected and monitored via colonoscopy. We here describe the surgical technique of segmental adeno-cre infection of the colon, the surveillance of the tumor via high-resolution colonoscopy and present the resulting colorectal tumors.

A protocol for the establishment of a genetically engineered mouse model of colorectal cancer by segmental adeno-cre infection and its surveillance via high-resolution colonoscopy is presented.

Despite the advantages of easy applicability and cost-effectiveness, colorectal cancer mouse models based on tumor cell injection have severe limitations ...

In Vivo Inhibition of MicroRNA to Decrease Tumor Growth in Mice

MicroRNAs (miRNAs) are important regulators of gene expression through their ability to destabilize mRNA and inhibit translation of target mRNAs. An ever-increasing number of studies have identified miRNAs as potential biomarkers for cancer diagnosis and prognosis, and also as therapeutic targets, adding an extra dimension to cancer evaluation and treatment. In the context of thyroid cancer, tumorigenesis results not only from mutations in important genes, but also from the overexpression of many miRNAs. Accordingly, the role of miRNAs in the control of thyroid gene expression is evolving as an important mechanism in cancer. Herein, we present a protocol to examine the effects of miRNA-inhibitor delivery as a therapeutic modality in thyroid cancer using human tumor xenograft and orthotopic mouse models. After engineering stable thyroid tumoral cells expressing GFP and luciferase, cells are injected into nude mice to develop tumors, which can be followed by bioluminescence. The in vivo inhibition of a miRNA can reduce tumor growth and upregulate miRNA gene targets. This method can be used to assess the importance of a determined miRNA in vivo, in addition to identifying new therapeutic targets.

This protocol describes xenograft and orthotopic mouse models of human thyroid tumorigenesis as a platform to test microRNA-based inhibitor treatments. This approach is ideal to study the function of non-coding RNAs and their potential as new therapeutic targets.

MicroRNAs (miRNAs) are important regulators of gene expression through their ability to destabilize mRNA and inhibit translation of target mRNAs. An ...

Evaluation of Colorectal Cancer Risk and Prevalence by Stool DNA Integrity Detection

Nowadays, stool DNA can be isolated and analyzed by several methods. The long fragments of DNA in stool can be detected by a qPCR assay, which provides a reliable probability of the presence of pre-neoplastic or neoplastic colorectal lesions. This method, called fluorescence long DNA (FL-DNA), is a fast, non-invasive procedure that is an improvement upon the primary prevention system. This method is based on evaluation of fecal DNA integrity by quantitative amplification of specific targets of genomic DNA. In particular, the evaluation of DNA fragments longer than 200 bp allows for detection of patients with colorectal lesions with very high specificity. However, this system and all currently available stool DNA tests present some general issues that need to be addressed (e.g., the frequency at which tests should be carried out and optimal number of stool samples collected at each timepoint for each individual). However, the main advantage of FL-DNA is the possibility to use it in association with a test currently used in the CRC screening program, known as the immunochemical-based fecal occult blood test (iFOBT). Indeed, both tests can be performed on the same sample, reducing costs and achieving a better prediction of the eventual presence of colorectal lesions.

The presented diagnostic FL-DNA kit is a time-saving and user-friendly method to determine the reliable probability of the presence of colorectal cancer lesions.

Nowadays, stool DNA can be isolated and analyzed by several methods. The long fragments of DNA in stool can be detected by a qPCR assay, which provides a ...

Micromanipulation of Circulating Tumor Cells for Downstream Molecular Analysis and Metastatic Potential Assessment

Blood-borne metastasis accounts for&#160;most cancer-related deaths and involves circulating tumor cells (CTCs) that are successful in establishing new tumors at distant sites. CTCs are found in the bloodstream of patients as single cells (single CTCs) or as multicellular aggregates (CTC clusters and CTC-white blood cell clusters), with the latter displaying a higher metastatic ability. Beyond enumeration, phenotypic and molecular analysis is extraordinarily important to dissect CTC biology and to identify actionable vulnerabilities. Here, we provide a detailed description of a workflow that includes CTC immunostaining and micromanipulation, ex vivo culture to assess&#160;proliferative and survival capabilities of individual cells, and in vivo metastasis-formation assays. Additionally, we provide a protocol to achieve the dissociation of CTC clusters into individual cells and the investigation of intra-cluster heterogeneity. With these approaches, for instance, we precisely quantify survival and proliferative potential of single CTCs and individual cells within CTC clusters, leading us to the observation that cells within clusters display better survival and proliferation in ex vivo cultures compared to single CTCs. Overall, our workflow offers a platform to dissect the characteristics of CTCs at the single cell level, aiming towards the identification of metastasis-relevant pathways and a better understanding of CTC biology.

Here, we present an integrated workflow to identify phenotypic and molecular features that characterize circulating tumor cells (CTCs). We combine live immunostaining and robotic micromanipulation of single and clustered CTCs with single cell-based techniques for downstream analysis and assessment of metastasis-seeding ability.

Blood-borne metastasis accounts for&#160;most cancer-related deaths and involves circulating tumor cells (CTCs) that are successful in establishing new ...

Detection and Monitoring of Tumor Associated Circulating DNA in Patient Biofluids

Complications associated with upfront and repeat surgical tissue sampling present the need for minimally invasive platforms capable of molecular sub-classification and temporal monitoring of tumor response to therapy. Here, we describe our dPCR-based method for the detection of tumor somatic mutations in cell free DNA (cfDNA), readily available in&#160;patient biofluids. Although limited in the number of mutations that can be tested for in each assay, this method provides a high level of sensitivity and specificity. Monitoring of mutation abundance, as calculated by MAF, allows for the evaluation of tumor response to therapy, thereby providing a much-needed supplement to radiographic imaging.

Here, we present a protocol to detect tumor somatic mutations in circulating DNA present in patient biological fluids (biofluids). Our droplet digital polymerase chain reaction (dPCR)-based method enables quantification of the tumor mutation allelic frequency (MAF), facilitating a minimally invasive complement to diagnosis and temporal monitoring of tumor response.

Complications associated with upfront and repeat surgical tissue sampling present the need for minimally invasive platforms capable of molecular ...

Semi-automatic PD-L1 Characterization and Enumeration of Circulating Tumor Cells from Non-small Cell Lung Cancer Patients by Immunofluorescence

Circulating tumor cells (CTCs) derived from the primary tumor are shed into the bloodstream or lymphatic system. These rare cells (1&#8722;10 cells per mL of blood) warrant a poor prognosis and are correlated with shorter overall survival in several cancers (e.g., breast, prostate and colorectal). Currently, the anti-EpCAM-coated magnetic bead-based CTC capturing system is the gold standard test approved by the U.S. Food and Drug Administration (FDA) for enumerating CTCs in the bloodstream. This test is based on the use of magnetic beads coated with anti-EpCAM markers, which specifically target epithelial cancer cells. Many studies have illustrated that EpCAM is not the optimal marker for CTC detection. Indeed, CTCs are a heterogeneous subpopulation of cancer cells and are able to undergo an epithelial-to-mesenchymal transition (EMT) associated with metastatic proliferation and invasion. These CTCs are able to reduce the expression of cell surface epithelial marker EpCAM, while increasing mesenchymal markers such as vimentin. To address this technical hurdle, other isolation methods based on physical properties of CTCs have been developed. Microfluidic technologies enable a label-free approach to CTC enrichment from whole blood samples. The spiral microfluidic technology uses the inertial and Dean drag forces with continuous flow in curved channels generated within a spiral microfluidic chip. The cells are separated based on the differences in size and plasticity between normal blood cells and tumoral cells. This protocol details the different steps to characterize the programmed death-ligand 1 (PD-L1) expression of CTCs, combining a spiral microfluidic device with customizable immunofluorescence (IF) marker set.

The characterization of circulating tumor cells (CTCs) is a popular topic in translational research. This protocol describes a semi-automatic immunofluorescence (IF) assay for PD-L1 characterization and enumeration of CTCs in non-small cell lung cancer (NSCLC) patient samples.

Circulating tumor cells (CTCs) derived from the primary tumor are shed into the bloodstream or lymphatic system. These rare cells (1&#8722;10 cells per mL ...

Detection of Cell-Free DNA in Blood Plasma Samples of Cancer Patients

Identifying mutations in tumors of cancer patients is a very important step in disease management. These mutations serve as biomarkers for tumor diagnosis as well as for the treatment selection and its response in cancer patients. The current gold standard method for detecting tumor mutations involves a genetic test of tumor DNA by means of tumor biopsies. However, this invasive method is difficult to be performed repeatedly as a follow-up test of the tumor mutational repertoire. Liquid biopsy is a new and emerging technique for detecting tumor mutations as an easy-to-use and non-invasive biopsy approach.
Cancer cells multiply rapidly. In parallel, numerous cancer cells undergo apoptosis. Debris from these cells are released into a patient&#8217;s circulatory system, together with finely fragmented DNA pieces, called cell-free DNA (cfDNA) fragments, which carry tumor DNA mutations. Therefore, for identifying cfDNA based biomarkers using liquid biopsy technique, blood samples are collected from the cancer patients, followed by the separation of plasma and buffy coat. Next, plasma is processed for the isolation of cfDNA, and the respective buffy coat is processed for the isolation of a patient&#39;s genomic DNA. Both nucleic acid samples are then checked for their quantity and quality; and analyzed for mutations using next-generation sequencing (NGS) techniques.
In this manuscript, we present a detailed protocol for liquid biopsy, including blood collection, plasma, and buffy coat separation, cfDNA and germline DNA extraction, quantification of cfDNA or germline DNA, and cfDNA fragment enrichment analysis.

In this paper we present a detailed protocol for non-invasive liquid biopsy technique, including blood collection, plasma and buffy coat separation, cfDNA and germline DNA extraction, quantification of cfDNA or germline DNA, and cfDNA fragment enrichment analysis.

Identifying mutations in tumors of cancer patients is a very important step in disease management. These mutations serve as biomarkers for tumor diagnosis ...