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Cancer Research

通过大刀DNA完整性检测评估结肠直肠癌风险和患病率

Published: June 8th, 2020

DOI:

10.3791/59426

1Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Italy, 2Diatech Pharmacogenetics srl

ERRATUM NOTICE

Important: There has been an erratum issued for this article. Read more …

提出的诊断FL-DNA试剂盒是一种节省时间和用户友好的方法,用于确定存在结肠直肠癌病变的可靠概率。

如今,凳子DNA可以通过几种方法进行分离和分析。通过qPCR测定可以检测粪便中DNA的长片段,它提供了出现前肿瘤或肿瘤性结肠直肠病变的可靠概率。这种方法,称为荧光长DNA(FL-DNA),是一个快速,非侵入性的程序,是一个改善的主要预防系统。该方法基于对基因组DNA特定靶点进行定量扩增,对粪便DNA完整性进行评估。特别是,对超过200bp的DNA片段的评估可以检测出具有极高特异性的结肠直肠病变患者。然而,该系统和所有目前可用的粪便DNA测试提出了一些需要解决的一般问题(例如,应进行测试的频率和在每个时间点为每个个体收集的粪便样本的最佳数量)。然而,FL-DNA的主要优点是有可能将其与目前用于CRC筛查程序的测试(称为免疫化学基粪便隐匿血测试(iFOBT)结合使用。事实上,两个测试都可以在同一样本上进行,从而降低成本,并更好地预测结肠直肠病变的最终存在。

结肠直肠癌(CRC)源于一个多步骤的过程,其中健康的上皮慢慢发展成腺瘤或息肉,随着时间的推移,它逐渐发展成恶性癌,2尽管CRC的发病率很高,但在过去十年中,死亡人数呈下降趋势。事实上,筛查计划采用的早期诊断工具已导致早期发现和去除肿瘤前腺瘤或息肉4。然而,由于不同的技术限制,这些方法都不是最佳的。事实上,为了提高灵敏度和特异性,许多粪便DNA测试都是单独提出的,或与当前常规诊断测试55、66结合提出。

通常,健康的粘血症会排入粪便流中凋亡的结肠细胞,而患病的粘卵菌会去角质非凋亡结肠细胞。长度为200bp或以上的片段是非凋亡DNA的特征。这种DNA被称为长DNA(L-DNA),已成为CRC早期诊断的可利用生物标志物。L-DNA可以从粪便标本中分离出来,并使用体外诊断FL-DNA试剂盒77、8、9、10、11、128,9,

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2013年至2015年,在梅尔多拉(FC,意大利FC)的科罗马诺洛科学组织(IRST)招募了患者。注册患者进入 IRSTB002 协议,经 IRST 道德委员会 - IRCCS AVR (25/10/2012,第 1 条) 批准。所有方法均按照相关准则和条例执行。所有患者均获得书面知情同意。

1. 从凳子中提取DNA

  1. 使用工具包准备凳子样本(参见材料表)。根据制造商的说明,通过执行萃取来选.......

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该协议的工作流如图1所示。工作流根据这些步骤结果提供两个控制步骤和不同的操作。首先,如果样本显示不适合的控件,则必须重复放大。其次,如果放大被抑制,样品必须从开始再加工或归类为无价值。

图 2显示了正负样本产生的荧光曲线。(A) 所示是合适的正样本的示例。HEX 通道上的采样信号在可接受的范围内。正信号高于 FAM .......

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先前的研究已经表明,由手动和半自动方法提取的粪便的DNA完整性分析,可以代表早期发现结肠直肠病变的替代方法,87、8、9、10、11、12。,9,10,11,12多年来,为检测结肠直肠癌开发了分子、非侵入性筛查测试,但由于方法耗时,与其他筛查测试相比?.......

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作者没有承认。

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NameCompanyCatalog NumberComments
1.5 mL and 2 mL polypropylene twist-lock tubes (DNase-, RNase-, DNA-, PCR inhibitor-free)Consumables required for DNA extraction and Real Time PCR
Absolute Ethanol (quality of analytical degree)Reagent required for DNA extraction
Benchtop centrifuge Maximum speed of 20000 x g. Instrument required for DNA extraction
EasyPGX analysis software version 2.0.0Diatech PharmacogeneticsRT800-SWAnalysis software 
EasyPGX centrifuge/vortex 8-well stripsDiatech PharmacogeneticsRT803Instrument recommended for the Real Time PCR assay
EasyPGX qPCR instrument 96 Diatech PharmacogeneticsRT800-96Instrument recommended for the Real Time PCR assay
EasyPGX ready FL-DNADiatech PharmacogeneticsRT029Kit required for the Real Time PCR assay
Micropipettes (volumes from 1 to 1.000 µL)Consumables required for DNA extraction and Real Time PCR
Powder-free disposable glovesConsumables required for DNA extraction and Real Time PCR
QIAamp Fast DNA StoolQiagen51604Kit recommended for the DNA extraction and purification from stool
Sterile filter tips DNase-, RNase-free (volumes from 1 to 1.000 µL)Consumables required for DNA extraction and Real Time PCR
Thermal block e.g. EasyPGX dry blockDiatech PharmacogeneticsRT801Instrument required for DNA extraction
Vortex e.g. EasyPGX centrifuge/vortex 1.5 ml Diatech PharmacogeneticsRT802Instrument required for DNA extraction

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Erratum

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

An erratum was issued for: Evaluation of Colorectal Cancer Risk and Prevalence by Stool DNA Integrity Detection. An affiliation was updated.

The first affiliation was updated from:

Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST)

to:

Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Italy

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