The authors thank Gr&#225;inne Tierney and Silvia Bellissimo for their editorial assistance.

该协议遵循IRST人类研究伦理委员会的指导方针。 注:在这个协议中，我们提取的DNA从尿液样本以进行DNA UCF完整性分析。 LNCaP和MRC细胞系用于构建标准。技术如DNA提取，DNA定量（分光光度计和实时PCR的对照基因，STOX1），以及对特定的癌基因的实时PCR进行（ 图1）。 1.尿液收集与处理<ol><li>获得清洁，干燥，塑料杯干净的副渔获物第一晨尿样品。收集至少50毫升的尿液样本。 </li><li>保持尿液，在4℃下不超过3小时，它在相同的温度发送至实验室。 </li><li>通过在实验室和转印到达时立即两次反相它分成两个50-mL锥形底聚丙烯管中混合各样品。 </li><li>离心管在850×g离心在4℃下或在室温下10分钟。 </li><li>小心转移10毫升尿上清的上部成两个5-mL管，而使细胞沉淀上面的上清液中的至少2毫升。 注意:传输上清液的上部降低污染的被细胞或细胞碎片的风险。有上部和下部部分之间没有明确的划分。 </li><li>弃沉淀，并立即在-80冻结上清液℃直至使用。 </li></ol> 2.从尿液上清，细胞系DNA分离注:来自细胞系隔离的DNA（ 例如，LNCAP前列腺癌或MRC膀胱癌）使用商业试剂盒并按照制造商的说明。应使用商业协议来执行从尿上清液DNA的分离，修改如下: <ol><li>解冻尿上清液在室温下的一个等分试样。&lt;/ LI&gt; <li>涡和混合尿样和转移尿上清液1毫升到一个清晰的5毫升管。冷冻在-80℃的残余尿。 </li><li>添加100微升蛋白酶K的直接向样品。 </li><li>添加1毫升AL缓冲到样品并吹打混匀。 </li><li>关闭管，并在56℃孵育样品15分钟。 </li><li>孵育期间，制备每个样品一列和制备洗涤缓冲液，AW1和AW2，按照制造商的说明（加100％的乙醇的指示量）。 </li><li>使样品回到室温，并添加1毫升的无水乙醇中。吹打充分拌匀。 </li><li>添加650微升在步骤2.7到塔中获得的混合物中，并在6000 xg离心离心它为1分钟。 </li><li>丢弃含有通流管，并放置在塔上的新的，干净的收集管。直到所有的样品混合物的已使用的（5次）重复步骤2.8和2.9。 </li><li>添加500＃181; l缓冲AW1无润湿柱的边缘。离心它在6000 xg离心1分钟。 </li><li>丢弃该管含有流通并用新的，干净的收集管更换。 </li><li>添加缓冲液AW2的500微升无润湿塔的边缘。全速（20,000 XG）3 min离心它。 </li><li>丢弃该管含有流通并用新的，干净的收集管更换。 </li><li>重复步骤2.12以除去任何残留的洗涤缓冲液。 </li><li>将列到一个干净的1.5毫升管。添加洗脱缓冲液AE中的50微升并等待7分钟，以确保缓冲区润湿列。 </li><li>离心它在8000 xg离心1分钟。 </li><li>吸管从步骤2.15洗脱液进入微型柱中，在最大速度离心它为1分钟，以确保DNA的最大回收。 </li></ol> 3. DNA定量和稀释<ol><li>使用分光光度计，从机器人进行DNA的定量小时的细胞系和尿上清液样品。使用2μL的样品在台式光谱仪，按照制造商的说明。 </li><li>稀释UCF DNA样品以获得1毫微克/微升的浓度，并于-20℃下将DNA储存，直到DNA的完整性分析。 注意:如果该DNA量不足以与实时PCR（至少100纳克）来进行，执行新的DNA分离过程。 </li><li>稀从细胞系样品的DNA，以获得六类标准不同浓度:0.001，0.01,0.1，1,0.5，和2纳克/微升，每100微升的体积（ST1，ST2，ST3，ST4，ST5，并ST6）。在-20℃直到DNA完整性分析存储细胞系DNA的标准。 </li></ol> 4. DNA完整性检测 - PCR <ol><li>解冻的引物（浓度取决于测定的类型），绿色超混合液，细胞系的DNA的标准，并在冰上UCF DNA稀释的样品。 </li><li>准备带管的托盘f或72孔转子盘。等分试样10μL的一式两份每个标准和稀释试样和无RNase水10μL的阴性对照。 </li><li>制备的每种引物的1微升的组合（浓度如表1所示），Green超12.5微升，和6.5微升的无RNase水各样品。当准备搭配，请使用以下的样本数量:6标准的2次重复，样品数量为2的重复，2重复阴性对照，以及2个额外的样本。 </li><li>分装15μL混合到每口井的。不要吸管或旋管。 </li><li>开始与在表1所示的PCR条件的协议。 注:29×2样品+ 6×2标准+阴性对照×2 = 72（UCF脱氧核糖核酸值）:对于在UCF脱氧核糖核酸值，29 DNA样品使用72孔转子盘中的每个实时实验处理。 注:为UCF DNA完整性分析该协议还可以使用另一个PCR实时仪（使用其他设备时，ROX染料可能需要添加）进行。 </li></ol> 5. DNA完整性检测 - 数据分析与解读注:各样品的UCF DNA值是通过使用标准曲线构造为每个单独的PCR基因评价，并使用标准曲线内插实时仪器检测系统软件获得，如先前所述7-9（ 图2）。 <ol><li>评估重复;样本复制与差≥1的Ct必须被丢弃，并在第二个实验中重新评估。 </li><li>计算位数的Ct每个样品和Ct值≤36考虑样本。 </li><li>评估使用熔点分析的PCR产物的特异性。 </li><li>通过评估与标准曲线插补每个扩增子的浓度;获得每个扩增子的浓度值（纳克/μL）。</li>
</ol>

<ol>
	<li>Francis, G., Stein, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circulating+Cell-Free+Tumour+DNA+in+the+Management+of+Cancer.">Circulating Cell-Free Tumour DNA in the Management of Cancer.</a> Int.J.Mol.Sci. 16 (6), 14122-14142 (2015).</li><li>Bryzgunova, O. E., Laktionov, P. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extracellular+Nucleic+Acids+in+Urine:+Sources,+Structure,+Diagnostic+Potential.">Extracellular Nucleic Acids in Urine: Sources, Structure, Diagnostic Potential.</a> Acta Naturae. 7 (3), 48-54 (2015).</li><li>Szarvas, 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=Deletion+analysis+of+tumor+and+urinary+DNA+to+detect+bladder+cancer:+urine+supernatant+versus+urine+sediment.">Deletion analysis of tumor and urinary DNA to detect bladder cancer: urine supernatant versus urine sediment.</a> Oncol.Rep. 18 (2), 405-409 (2007).</li><li>Togneri, F. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genomic+complexity+of+urothelial+bladder+cancer+revealed+in+urinary+cfDNA.">Genomic complexity of urothelial bladder cancer revealed in urinary cfDNA.</a> Eur.J.Hum.Genet. , (2016).</li><li>Zonta, E., Nizard, P., Taly, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+DNA+Integrity,+Applications+for+Cancer+Research.">Assessment of DNA Integrity, Applications for Cancer Research.</a> Adv.Clin.Chem. 70, 197-246 (2015).</li><li>Hao, T. B., 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=Circulating+cell-free+DNA+in+serum+as+a+biomarker+for+diagnosis+and+prognostic+prediction+of+colorectal+cancer.">Circulating cell-free DNA in serum as a biomarker for diagnosis and prognostic prediction of colorectal cancer.</a> Br.J.Cancer. 111 (8), 1482-1489 (2014).</li><li>Salvi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Urine+Cell-Free+DNA+Integrity+Analysis+for+Early+Detection+of+Prostate+Cancer+Patients.">Urine Cell-Free DNA Integrity Analysis for Early Detection of Prostate Cancer Patients.</a> Dis.Markers. 2015, 574120 (2015).</li><li>Casadio, 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=Urine+cell-free+DNA+integrity+as+a+marker+for+early+prostate+cancer+diagnosis:+a+pilot+study.">Urine cell-free DNA integrity as a marker for early prostate cancer diagnosis: a pilot study.</a> Biomed.Res.Int. 2013, 270457 (2013).</li><li>Casadio, 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=Urine+cell-free+DNA+integrity+as+a+marker+for+early+bladder+cancer+diagnosis:+preliminary+data.">Urine cell-free DNA integrity as a marker for early bladder cancer diagnosis: preliminary data.</a> Urol.Oncol. 31 (8), 1744-1750 (2013).</li><li>Salvi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circulating+cell-free+AR+and+CYP17A1+copy+number+variations+may+associate+with+outcome+of+metastatic+castration-resistant+prostate+cancer+patients+treated+with+abiraterone.">Circulating cell-free AR and CYP17A1 copy number variations may associate with outcome of metastatic castration-resistant prostate cancer patients treated with abiraterone.</a> Br.J.Cancer. 112 (10), 1717-1724 (2015).</li><li>Ishkanian, A. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-resolution+array+CGH+identifies+novel+regions+of+genomic+alteration+in+intermediate-risk+prostate+cancer.">High-resolution array CGH identifies novel regions of genomic alteration in intermediate-risk prostate cancer.</a> Prostate. 69 (10), 1091-1100 (2009).</li><li>Oxley, J. D., Winkler, M. H., Gillatt, D. A., Peat, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Her-2/neu+oncogene+amplification+in+clinically+localised+prostate+cancer.">Her-2/neu oncogene amplification in clinically localised prostate cancer.</a> J.Clin.Patho. 55 (2), 118-120 (2002).</li><li>Nord, 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=Focal+amplifications+are+associated+with+high+grade+and+recurrences+in+stage+Ta+bladder+carcinoma.">Focal amplifications are associated with high grade and recurrences in stage Ta bladder carcinoma.</a> Int.J.Cancer. 126 (6), 1390-1402 (2010).</li><li>Tabach, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amplification+of+the+20q+chromosomal+arm+occurs+early+in+tumorigenic+transformation+and+may+initiate+cancer.">Amplification of the 20q chromosomal arm occurs early in tumorigenic transformation and may initiate cancer.</a> PLoS One. 6 (1), e14632 (2011).</li></ol>

The authors declare no competing financial interests.

UCF DNA完整性分析是在尿评估DNA完整性一种新的，非侵入性的方法。它最近提出了膀胱9和前列腺癌7,8的早期诊断。有许多优点和UCF DNA完整性检测的缺点在这里讨论，未来的前景一起。 该方法的主要优点是，它提供了一种廉价的，非侵入性的方法和简单的协议来研究尿作为生物标志物的一个潜在来源，只需要的分子生物学技术的基本知识。该测试是快速执行，...

无细胞的DNA可以在血液和尿液由于细胞死亡通过细胞凋亡或坏死的机制来检测。血液中的游离细胞DNA已被广泛地研究了在各种疾病的诊断和预后目的，尤其是癌症1。然而，较少有人知道尿无细胞（UCF）DNA的作用。 UCF DNA可以从血液穿过肾小球滤过系统或从直接来与该体液2（ 例如，上皮细胞或前列腺细胞）接触的细胞产生。作为生物标志物的来源，使用的UCF的DNA已经主要研究了肾，膀胱癌，和前列腺癌的早期诊断由于UCF的DNA直接从尿道细胞3,4-未来的高百分比。 鲜为人知的是，UCF DNA以及分离和鉴定的最佳方法。给定的假设肿瘤细胞释放比正常细胞较长的DNA片段，评价无细胞DNA完整性已被研究以试图阐明DNA的原点在血液循环中5。一些研究表明，在血液中的游离细胞DNA完整性表示用于多种癌症6良好的诊断测试，并且在同一假设已经关于拟尿7-9。 本文介绍了一个潜在的应用膀胱和前列腺癌检测DNA UCF完整性分析的新方法。特别是，UCF DNA的完整性片段长度大于250 bp的已知的4个区域测试，以在实体肿瘤，包括前列腺癌和膀胱癌增加的DNA拷贝数:C-MYC（8q24.21），HER2（17q12.1 ），BCAS1（20q13.2）和AR（Xq12）10-14。特定癌基因，而不是随机的序列，被选择来增加癌症患者的无细胞级分发现它们的概率。之一的主要优点这种方法是，它是柔性的，并且其他区域也可以被肿瘤的类型和特性的基础上选择的。

<table border="0" cellpadding="0" cellspacing="0" width="779">
	<tbody>
		<tr height="63">
			<td height="63" style="height:63px;width:277px;">QIAamp DNA Mini Kit 
			&#160;</td>
			<td style="width:216px;">Qiagen</td>
			<td style="width:119px;">51304</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:277px;">iQ SYBR&#160;Green Supermix, 100 x 50 &#181;l rxns, 2.5 ml (2 x 1.25 ml)</td>
			<td style="width:216px;">Biorad</td>
			<td style="width:119px;">1708880</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:277px;">IDT custom DNA oligos&#160;</td>
			<td style="width:216px;">IDT&#160;</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">HPLC purification, 100nMole DNA oligo</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;">NanoDrop 1000 Spectrophotometer</td>
			<td style="width:216px;">Thermo Scientific</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Other spectrophotometric methods could also be used to quantify DNA</td>
		</tr>
		<tr height="74">
			<td height="74" style="height:74px;width:277px;">Rotor-Gene 6000</td>
			<td style="width:216px;">Corbett</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Another Real Time PCR instrument could also be used</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">microcentrifuge</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">one centrifuge for 50 ml tubes</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">incubator</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">&#160;-80&#176;C freezer</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">-20&#176;C freezer</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">10 ul pipette</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">20 ul pipette</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">200 ul pipette</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">1000 ul pipette</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">pipette tips (10;20;200;1000)</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">1,5 ml tubes</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">50ml tubes</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">15 ml tubes</td>
			<td style="width:216px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">Rotor-Disc 72 Rotor</td>
			<td style="width:216px;">Corbett</td>
			<td>&#160;9018899</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Strip Tubes and Caps, 0.1 ml (250)</td>
			<td style="width:216px;">Qiagen</td>
			<td style="width:119px;">981103</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">Collection Tubes (2 ml)</td>
			<td style="width:216px;">Qiagen</td>
			<td style="width:119px;">19201</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">Buffer AL (264 ml)</td>
			<td style="width:216px;">Qiagen</td>
			<td style="width:119px;">19075</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:277px;">Proteinase K (10ml)</td>
			<td style="width:216px;">Qiagen</td>
			<td style="width:119px;">19133</td>
			<td></td>
		</tr>
	</tbody>
</table>

cell-free dna integrity analysis in urine samples

尽管在血浆或血清中的循环无细胞DNA的存在已被广泛证明是生物标记物的合适来源为许多类型的癌症，很少研究都集中在可能利用尿无细胞（UCF）的DNA。从正常凋亡细胞产生高度片段化DNA的假设和癌细胞开始释放更长的DNA，评价为能够患者前列腺或膀胱癌和健康个体之间进行区分的早期诊断标志物的UCF DNA完整性的潜在作用。 一个UCF DNA完整性分析，提出的超过250 bp的长四个序列四个实时定量PCR的基础上:C-MYC，BCAS1，HER2和AR。经常有在膀胱和前列腺癌的增加的DNA拷贝数序列被选择用于分析，但该方法是灵活的，这些基因可以与INTE的其他基因被取代休息。 UCF的DNA作为生物标志物的来源的潜在效用已被证实为泌尿系统恶性肿瘤，从而为在UCF DNA鉴定进一步研究的方式。在UCF DNA完整性测试具有作为非侵入性，快速，容易执行，以进行分析所需的尿只有几毫升的优点。

总游离DNA浓度是通过分光光度法量化的所有样品进行分析，呈现出范围1.51和138之间纳克/微升。五个控制样品用于数据的再现性:两个独立的实时实验对c-MYC，HER2，BCAS1，AR和STOX1进行。变化（CV）的系数，然后计算每个基因（ 表2），用两个独立的实验之间的良好度再现性（ 表2）。 <p class="jove_content" fo:keep...

Watch this Scientific Journal Video about Cell-Free DNA Integrity Analysis in Urine Samples at JoVE.com

Cell-Free DNA Integrity Analysis in Urine Samples

A method for analyzing DNA integrity in the cell-free supernatant fraction of urine samples is proposed. The method is suitable for early detection of urological malignancies and has proven accurate for the early diagnosis of bladder cancer.

无细胞DNA完整性分析尿样中

Although the presence of circulating cell-free DNA in plasma or serum has been widely shown to be a suitable source of biomarkers for many types of ...

cell-free-dna-integrity-analysis-in-urine-samples

Research

JoVE Journal

Cancer Research

13.7K 次观看.  Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS. A method for analyzing DNA integrity in the cell-free supernatant fraction of urine samples is proposed. The method is suitable for early detection of urological malignancies and has proven accurate for the early diagnosis of bladder cancer.

视频: Cell-Free DNA Integrity Analysis in Urine Samples

Harnessing the DNA Dye-triggered Side Population Phenotype to Detect and Purify Cancer Stem Cells from Biological Samples

Cancer is a stem cell-driven disease and eradication of these cells has become a major therapeutic goal. Deciphering vulnerabilities of Cancer Stem Cells (CSCs) and identifying suitable molecular targets relies on methods that allow their specific discrimination in heterogeneous samples such as cell lines and ex vivo tumor tissue. Flow cytometry/FACS is a powerful technology to multi-parametrically dissect biological samples at the single cell level and is to date the method of choice to recover live cells for downstream analyses. Surface markers such as CD44 and CD133 as well as detection of aldehyde dehydrogenase enzymatic activity have often been used to define and sort out CSCs from tumor samples by FACS. A complementary approach, depicted here in methodological detail, makes use of functional dye extrusion by ABC drug transporters, which identifies a distinct population of fluorescence-dim cells commonly referred to as side population (SP). SP&#160;cancer cells exhibit canonical stem cell characteristics and can be abrogated and functionally confirmed using agents that inhibit the dye-extruding drug transporter (most frequently ABCB1/P-glycoprotein/MDR1/CD243 and ABCG2/Bcrp1/CD338). Moreover, the SP&#160;assay is compatible with other flow cytometric evaluations such as staining of surface antigens, aldehyde dehydrogenase detection and dead cell discrimination (e.g., with 7-AAD or propidium iodide (PI)). Thus, we describe a valuable and broadly applicable method for CSC identification, isolation and sub-characterization mechanistically based on a functional, rather than a phenotypic parameter. Although originally performed with Hoechst 33342 as triggering dye, we here focus on the more recent Violet dye-based SP phenotype that is resolvable on any flow cytometer equipped with a violet laser source.

Methods allowing the characterization and isolation of stem cell populations from biological samples are critical for the advance of stem cell-targeted treatments in cancer and beyond. Here, we provide a detailed protocol for cancer stem cell isolation using the dye-triggered side population phenotype.

利用DNA染色体引发的侧群体表型，从生物样品中检测和纯化癌细胞

Cancer is a stem cell-driven disease and eradication of these cells has become a major therapeutic goal. Deciphering vulnerabilities of Cancer Stem Cells ...

科研

癌症研究

Evaluating In Vitro DNA Damage Using Comet Assay

DNA damage is a common phenomenon for each cell during its lifespan, and is defined as an alteration of the chemical structure of genomic DNA. Cancer therapies, such as radio- and chemotherapy, introduce enormous amount of additional DNA damage, leading to cell cycle arrest and apoptosis to limit cancer progression. Quantitative assessment of DNA damage during experimental cancer therapy is a key step to justify the effectiveness of a genotoxic agent. In this study, we focus on a single cell electrophoresis assay, also known as the comet assay, which can quantify single and double-strand DNA breaks in vitro. The comet assay is a DNA damage quantification method that is efficient and easy to perform, and has low time/budget demands and high reproducibility. Here, we highlight the utility of the comet assay for a preclinical study by evaluating the genotoxic effect of olaparib/temozolomide combination therapy to U251 glioma cells.

Evaluating In Vitro DNA Damage Using Comet Assay

The comet assay is an efficient method to detect DNA damage including single and double-stranded DNA breaks. We describe alkaline and neutral comet assays to measure DNA damage in cancer cells to evaluate the therapeutic effect of chemotherapy.

利用彗星试验评价体外DNA 损伤

DNA damage is a common phenomenon for each cell during its lifespan, and is defined as an alteration of the chemical structure of genomic DNA. Cancer ...

Simple and Rapid Method to Obtain High-quality Tumor DNA from Clinical-pathological Specimens Using Touch Imprint Cytology

It is critical to determine the mutational status in cancer before administration and treatment of specific molecular targeted drugs for cancer patients. In the clinical setting, formalin-fixed paraffin-embedded (FFPE) tissues are widely used for genetic testing. However, FFPE DNA is generally damaged and fragmented during the fixation process with formalin. Therefore, FFPE DNA is sometimes not adequate for genetic testing because of low quality and quantity of DNA. Here we present a method of touch imprint cytology (TIC) to obtain genomic DNA from cancer cells, which can be observed under a microscope. Cell morphology and cancer cell numbers can be evaluated using TIC specimens. Furthermore, the extraction of genomic DNA from TIC samples can be completed within two days. The total amount and quality of TIC DNA obtained using this method was higher than that of FFPE DNA. This rapid and simple method allows researchers to obtain high-quality DNA for genetic testing (e.g., next generation sequencing analysis, digital PCR, and quantitative real time PCR) and to shorten the turnaround time for reporting results.

Obtaining high-quality genomic DNA from tumor tissues is an essential first step for analyzing genetic alterations using next generation sequencing. In this article, we present a simple and rapid method to enrich tumor cells and obtain intact DNA from touch imprint cytology specimens.

用触印细胞学方法快速获得临床病理标本中高质量肿瘤 DNA

It is critical to determine the mutational status in cancer before administration and treatment of specific molecular targeted drugs for cancer patients. ...

Using 22C3 Anti-PD-L1 Antibody Concentrate on Biopsy and Cytology Samples from Non-small Cell Lung Cancer Patients

Pembrolizumab monotherapy has been approved for the first- and second-line treatment of patients with PD-L1-expressing advanced non-small cell lung cancer (NSCLC). Testing for PD-L1 expression with the PD-L1 immunohistochemistry (IHC) 22C3 companion diagnostic assay, which gives a tumor proportion score (TPS), has been validated on tumor tissue. We developed an optimized laboratory-developed test (LDT) that uses the 22C3 antibody (Ab) concentrate on a widely available IHC autostainer for biopsy and cytology specimens. The PD-L1 TPS was evaluated with 120 paired whole-tumor tissue sections and biopsy samples and with 70 paired biopsy and cytology samples (bronchial washes, n = 40; pleural effusions, n = 30). The 22C3 Ab concentrate-based LDT showed a high concordance rate between biopsy (~100%) and cytology (~95%) specimens when compared to PD-L1 IHC expression determined using the PD-L1 IHC 22C3 companion assay at both TPS cut points (&#8805;1%, &#8805;50%). The optimized LDT presented here, using the 22C3 Ab concentrate to determine the PD-L1 expression in both tumor tissue and in cytology specimens, will expand the ability of laboratories worldwide to assess the eligibility of patients with NSCLC for treatment with pembrolizumab monotherapy in a reliable and reproducible manner.

To expand the ability of laboratories worldwide to assess the eligibility of patients with lung cancer for treatment with pembrolizumab, in a reliable and reproducible manner, we developed an assay that uses the 22C3 antibody concentrate on a widely available immunohistochemical autostainer, for both biopsy and cytology specimens.

22C3 Anti-PD-L1 抗体精矿在非小细胞肺癌活检及细胞学标本中的应用

Pembrolizumab monotherapy has been approved for the first- and second-line treatment of patients with PD-L1-expressing advanced non-small cell lung cancer ...

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.

通过大刀DNA完整性检测评估结肠直肠癌风险和患病率

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 ...

Testing Targeted Therapies in Cancer using Structural DNA Alteration Analysis and Patient-Derived Xenografts

We present here an integrative approach for testing efficacy of targeted therapies that combines the next generation sequencing technolo-gies, therapeutic target analyses and drug response monitoring using patient derived xenografts (PDX). This strategy was validated using ovarian tumors as an example. The mate-pair next generation sequencing (MPseq) protocol was used to identify structural alterations and followed by analysis of potentially targetable alterations. Human tumors grown in immunocompromised mice were treated with drugs selected based on the genomic analyses. Results demonstrated a good correlation between the predicted and the observed responses in the PDX model. The presented approach can be used to test the efficacy of combination treatments and aid personalized treatment for patients with recurrent cancer, specifically in cases when standard therapy fails and there is a need to use drugs off label.

Here we present a protocol to test the efficacy of targeted therapies selected based on the genomic makeup of a tumor. The protocol describes identification and validation of structural DNA rearrangements, engraftment of patients&#8217; tumors into mice and testing responses to corresponding drugs.

使用结构DNA改变分析和患者衍生异种移植测试癌症的靶向疗法

We present here an integrative approach for testing efficacy of targeted therapies that combines the next generation sequencing technolo-gies, therapeutic ...

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.

在结肠直肠癌细胞的三维球体培养物中使用无细胞益生菌超常剂评估细胞死亡

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

Genome-Wide Analysis of DNA Methylation in Gastrointestinal Cancer

DNA methylation is an important epigenetic change that is biologically meaningful and a frequent focus of cancer research. Genome-wide DNA methylation is a useful measure to provide an accurate analysis of the methylation status of gastrointestinal (GI) malignancies. Given the multiple potential translational uses of DNA methylation analysis, practicing clinicians and others new to DNA methylation studies need to be able to understand step by step how these genome-wide analyses are performed. The goal of this protocol is to provide a detailed description of how this method is used for the biomarker identification in GI malignancies. Importantly, we describe three critical steps that are needed to obtain accurate results during genome-wide analysis. Clearly and concisely written, these three methods are often lacking and not noticeable to those new to epigenetic studies. We used 48 samples of a GI malignancy (gastric cancer) to highlight practically how genome-wide DNA methylation analysis can be performed for GI malignancies.

Herein, we describe a procedure for genome-wide analysis of DNA methylation in gastrointestinal cancers. The procedure is of relevance to studies that investigate relationships between methylation patterns of genes and factors contributing to carcinogenesis in gastrointestinal cancers.

胃肠癌DNA甲基化基因组全谱分析

DNA methylation is an important epigenetic change that is biologically meaningful and a frequent focus of cancer research. Genome-wide DNA methylation is ...

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.

癌症患者血浆样本中无细胞DNA检测

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

A Standardized Liquid Biopsy Preanalytical Protocol for Downstream Circulating-Free DNA Applications

The term liquid biopsy (LB) refers to molecules such as proteins, DNA, RNA, cells, or extracellular vesicles in blood and other bodily fluids that originate from the primary and/or metastatic tumor. LB has emerged as a mainstay in translational research and has started to become part of clinical oncology practice, providing a minimally invasive alternative to solid biopsy. The LB allows real-time monitoring of a tumor via a minimally invasive sample extraction, such as blood. The applications include early cancer detection, patient follow-up for the detection of disease progression, assessment of minimal residual disease, and potential identification of molecular progression and mechanism of resistance. In order to achieve a reliable analysis of these samples that can be reported in the clinic, the preanalytical procedures should be carefully considered and strictly followed. Sample collection, quality, and storage are crucial steps that determine their usefulness in downstream applications. Here, we present standardized protocols from our liquid biopsy working module for collecting, processing, and storing plasma and serum samples for downstream liquid biopsy analysis based on circulating-free DNA. The protocols presented here require standard equipment and are sufficiently flexible to be applied in most laboratories focused on biological procedures.

The liquid biopsy has revolutionized our approach to oncology translational studies, with sample collection, quality, and storage being crucial steps for its successful clinical application. Here we describe a standardized and validated protocol for downstream circulating-free DNA applications that can be applied in most translational research laboratories.