纳米通道技术及应用

纳米通道技术是近年来发展的一种直接解读核酸分子编码信息的新方法,它通过将单链核酸上的核苷酸序列直接转化为电信号,能以每秒超过1 000个碱基的速度对其进行超快速序列分析,较现有测序方法更简便快速和省钱.该技术除可用于核酸超快速外,还在病原体基因诊断、单核苷酸多态性和样品多成分的快速检测等多个领域有重要用途.     

血浆microRNA在早期乳腺癌诊断中的价值

目的：探讨不同microRNA的表达及评估血浆microRNA作为早期乳腺癌诊断的新标志物的价值。方法：我们收集了49例早期乳腺癌的术前血浆作为实验样本和36例健康女性血浆作为对照样本。应用反转录和实时荧光定量聚合酶链反应,我们检测miR-21,miR-205,miR-222这三个候选基因的相对表达量并分析了这三个候选microRNA表达与临床病理特征的关系。结果：我们发现,与健康对照相比,miR-21（1．565,P=0．022）andmiR-222（2．258,P〈0．001）在乳腺癌病人血浆中的表达明显升高,而miR-205（0．591,P=0．001）在乳腺癌病人血浆中的表达明显下降。并且在临床病例资料数据的比较中,miR-21（P=0．0101）在乳腺癌病人中的表达水平与雌激素受体和孕激素受体相关。血浆中miR-222的表达水平在肿瘤不同分期中明显不同。结论：本实验证明miR一21,miR-205andmiR．222的表达水平与乳腺癌的病理特征明显相关,可以作为乳腺癌的潜在标志物。     

玻璃粘连蛋白血清学检测对乳腺癌早期诊断价值的初步研究

目的:探讨玻璃粘连蛋白血清学表达与乳腺癌早期诊断的相关性。方法:采用酶联免疫吸附试验(ELISA)定量测定62例乳腺癌(0-Ⅰ期癌22例,Ⅱ-Ⅲ期癌40例)和8例乳腺良性病变患者血清玻璃粘连蛋白水平,分析玻璃粘连蛋白表达在良性与各期乳腺癌中的变化规律,同时比较CA153、CA125、CEA的表达情况。结果:0-Ⅰ期乳腺癌组血清玻璃粘连蛋白的表达水平(231.45±30.54μg/m L)显著高于良性对照组(197.84±24.31μg/m L)和Ⅱ-Ⅲ期乳腺癌组(209.34±31.25μg/m L),差异均有统计学意义(P0.01);玻璃粘连蛋白血清表达水平与乳腺癌组织学分级、年龄、肿瘤大小、月经状况、ER、PR、Her-2及Ki-67表达无关(P0.05);而血清CA153、CA125、CEA表达水平随着临床分期升高而升高,其中CA153的表达存在统计学差异(P0.05)。结论:血清玻璃粘连蛋白水平在早期阶段乳腺癌(0-Ⅰ期)显著高于良性和中期(Ⅱ-Ⅲ期)乳腺癌患者,提示玻璃粘连蛋白可能是一项有潜力的乳腺癌早期诊断指标,而血清CA153、CA125、CEA表达则主要与乳腺癌病情发展相关。     

肿瘤标志物联合检测在乳腺癌早期诊断中的应用

目的：探讨肿瘤标志物癌胚抗原（CEA）、糖链抗原19-9（CA19-9）、糖链抗原15-3（CA15-3）联合检测在乳腺癌早期诊断中的应用价值。方法：检测87例乳腺癌患者,55例乳腺良性肿瘤患者和35例健康人血清中CEA、CA19-9、CA153等肿瘤标志物的水平及3种标志物不同组合对乳腺癌的阳性检出率。结果：乳腺癌患者3种肿瘤标志物显著高于正常对照组及乳腺良性肿瘤组（P〈0.01）。3项标志物不同组合对不同分期乳腺癌检出的敏感性均高于单项标志物。其中CEA＋CA199＋CA153组合的检出敏感性较其他组合均高,特别是对早期患者检出率明显提高。结论：CEA＋CA199＋CA153联合检测能提高乳腺癌的早期诊断率。     

循环microRNAs的外泌形成机制及其对乳腺癌侵袭和转移的影响

目前乳腺癌的临床诊疗主要依赖影像学和相对较少的预后/预测指标(如雌激素受体、孕激素受体、HER2等).这些生物标志物主要是基于原发肿瘤病灶的生物学检测,可用于转移或复发的检测指标很少,尤其是在切除肿瘤原发灶后,复发监测很困难.循环cell-free microRNAs(circulating cf-miRNAs,或简称circulating miRNAs)的发现为改变现有乳腺癌临床诊疗模式提供了可能.Cell-free miRNA通过外泌体、微囊或转运蛋白的主动外泌机制,可能在循环miRNA的形成中起着重要作用.Cell-free miRNA特别是circulating miRNA不仅自身可以作为信号分子影响肿瘤细胞和组织微环境,而且还可以与其他信号通路发生交互通讯来调控肿瘤部位新生血管的形成和肿瘤细胞表型的上皮-间质转换,影响乳腺癌的侵袭和转移.本文综述了循环miRNA的特征与分泌机制,特别是乳腺癌相关的循环miRNA参与作为一种液体活检生物标志物在乳腺癌诊断、预后评价和疗效评估的临床意义.     

肿瘤标志物联合检测在乳腺癌早期诊断中的应用

目的:探讨肿瘤标志物癌胚抗原(CEA)、糖链抗原19-9(CA19-9)、糖链抗原15-3(CA15-3)联合检测在乳腺癌早期诊断中的应用价值。方法:检测87例乳腺癌患者,55例乳腺良性肿瘤患者和35例健康人血清中CEA、CA19-9、CA153等肿瘤标志物的水平及3种标志物不同组合对乳腺癌的阳性检出率。结果:乳腺癌患者3种肿瘤标志物显著高于正常对照组及乳腺良性肿瘤组(P<0.01)。3项标志物不同组合对不同分期乳腺癌检出的敏感性均高于单项标志物。其中CEA+CA199+CA153组合的检出敏感性较其他组合均高,特别是对早期患者检出率明显提高。结论:CEA+CA199+CA153联合检测能提高乳腺癌的早期诊断率。     

早期乳腺癌的诊断及治疗进展

乳腺癌是全球女性最常见的恶性肿瘤。多年来早期乳腺癌是乳腺肿瘤学家积极关注的焦点之一。早期乳腺癌的长期治愈率达90%以上,其诊断率的提高将大大提高病人的生存率和生存年限,降低病死率。生活方式、环境因素、遗传基因等都是乳腺癌的危险因素。近年来早期乳腺癌发生率不断上升,并趋于年轻化,所以早期预防、早期发现、早期治疗成了治疗早期乳腺癌的关键。早期乳腺癌的治疗从传统的手术治疗发展到以手术为主,放化疗为辅的综合疗法。随着社会的进步和经济的发展,早期乳腺癌的治疗方案渐渐趋于完整。现对早期乳腺癌的诊断和治疗研究进展进行概述,以指导临床。     

乳腺癌早期筛查和诊断生物标志物研究进展

2020年全球乳腺癌(breast cancer,BC)新发病例达226万例,占全部肿瘤新发病例的11.7%,是全世界发病率最高的癌症。早期发现、早期诊断和早期治疗是降低乳腺癌死亡率及改善预后的关键。尽管乳房X光筛查被广泛用作乳腺癌筛查的工具,但其假阳性、辐射性和过度诊断仍是亟待解决的问题。因此,亟需开发易于获取且稳定可靠的生物标志物,用于乳腺癌无创筛查和诊断。近年来多项研究显示来自乳腺癌患者血液中的循环肿瘤细胞DNA(circulating tumor cell DNA,ctDNA)、癌胚抗原(carcinoembryonic antigen,CEA)、糖类抗原15-3(carbohydrate antigen 15-3,CA15-3)、细胞外囊泡(extracellular vesicles,EV)、循环miRNA和BRCA基因突变等生物标志物,以及来自人体尿液、呼出气体(volatile organic compounds,VOCs)和乳头吸出液(nipple aspirate fluid,NAF)中的磷脂、miRNA、苯乙酮和十六烷等多种生物标志物与乳腺癌早期筛查和诊断密切相关。本文综述了上述生物标志物在乳腺癌早期筛查和诊断中的应用。     

miR-424对雌激素受体α表达的抑制作用

目的:筛选能够抑制在乳腺癌发生中起关键作用的雌激素受体α(ERα)表达的microRNA(miRNA)分子,并在ERα阳性的乳腺癌细胞株中初步检测其生物学功能。方法:在ERα阳性的乳腺癌细胞ZR75-1中转染多种miRNA的表达载体,Western印迹检测ERα的表达水平,找到可以抑制ERα表达的miRNA分子;将该miRNA的表达载体转染ZR75-1后,在雌激素E2的作用下,检测该miRNA分子对细胞生长的影响。结果:经过筛选,得到能够抑制ERα表达的miRNA分子miR-424;生长曲线结果显示,miR-424能够在不依赖于E2的情况下阻抑ZR75-1的生长。结论:该研究为进一步研究miR-424在ERα信号通路中的生物学功能及研究乳腺癌的发生发展机制奠定了基础。     

血清多肿瘤标志物蛋白芯片检测在乳腺癌诊断中的价值

目的:探讨血清多肿瘤标志物蛋白芯片检测系统在乳腺癌诊断中的临床价值。方法:临床确诊的乳腺癌患者307例为乳腺癌组,非乳腺癌的其他恶性肿瘤患者495例为对照组。应用多肿瘤标志物蛋白芯片检测系统检测12种肿瘤标志物水平,评价血清肿瘤标志物的在乳腺癌组与对照组之间的差异。结果:CA153,CEA,Free-PSA这三项指标为诊断乳腺癌的独立相关因素(P<0.05),比较三项指标ROC曲线下面积可见,CA153对于鉴别乳腺癌准确性更高,其敏感性、特异性分别为78.92和56.14,女性乳腺癌患者Free-PSA可见明显升高,对乳腺癌有特殊提示意义,手术前后标志物CA199、CA242、Ferrin、CA125水平差异有统计学意义。结论:在临床常用的肿瘤标记物中,CA153,CEA,Free_PSA水平的升高与乳腺癌发生独立相关,其中CA153具有更高的诊断准确性,Free_PSA水平升高对乳腺癌的诊断有特别提示意义。     

基于纳米孔测序技术的柑橘黄龙病检测方法建立

柑橘黄龙病(Huanglongbing)是柑橘生产上最具毁灭性的病害,及时快速地进行早期检测和诊断是防控黄龙病的关键措施之一.本文利用掌上纳米孔测序仪MinION对携带黄龙病菌Candidatus Liberibacter asiaticus的DNA样品进行测序,并利用Blast、GraphMap、minimap2以及两种bwa的比对方法将测序结果比对到黄龙病菌基因组上,比对结果均匀的比对到黄龙病菌基因组上,并未发现严重的偏倚现象,验证了其测序结果的可靠性.本技术可弥补因柑橘木虱Diaphorina citri(Kuwayama)虫体过小或损坏难以进行光学识别的不足,并可同时检测虫体是否携带有黄龙病菌,对有黄龙病发生风险但尚未有黄龙病实际发生的柑橘种植区提供实时实地的监控与预警.     

Automated breast cancer diagnosis based on fine needle aspiration

OBJECTIVE: To design and analyze an automated diagnostic system for breast carcinoma based on fine needle aspiration (FNA). STUDY DESIGN: FNA is a noninvasive alternative to surgical biopsy for the diagnosis of breast carcinoma. Widespread clinical use of FNA is limited by the relatively poor interobserver reproducibility of the visual interpretation of FNA images. To overcome the reproducibility problem, past research has focused on the development of automated diagnosis systems that yield accurate, reproducible results. While automated diagnosis is, by definition, reproducible, it has yet to achieve diagnostic accuracy comparable to that of surgical biopsy. In this article we describe a sophisticated new diagnostic system in which the mean sensitivity (of FNA diagnosis) approaches that of surgical biopsy. The diagnostic system that we devised analyzes the digital FNA data extracted from FNA images. To achieve high sensitivity, the system needs to solve large, equality-constrained, integer nonlinear optimization problems repeatedly. Powerful techniques from the theory of Lie groups and a novel optimization technique are built into the system to solve the underlying optimization problems effectively. The system is trained using digital data from FNA samples with confirmed diagnosis. To analyze the diagnostic accuracy of the system > 8,000 computational experiments were performed using digital FNA data from the Wisconsin Breast Cancer Database. RESULTS: The system has a mean sensitivity of 99.62% and mean specificity of 93.31%. Statistical analysis shows that at the 95% confidence level, the system can be trusted to correctly diagnose new malignant FNA samples with an accuracy of 99.44-99.8% and new benign FNA samples with an accuracy of 92.43-93.93%. CONCLUSION: The diagnostic system is robust and has higher sensitivity than do all the other systems reported in the literature. The specificity of the system needs to be improved.     

microRNAs in breast cancer: regulatory roles governing the hallmarks of cancer

A large number of etiological factors and the complexity of breast cancers present challenges for prevention and treatment. Recently, the emergence of microRNAs (miRNAs) as cancer biomarkers has added an extra dimension to the ‘molecular signatures’ of breast cancer. Bioinformatic analyses indicate that each miRNA can regulate hundreds of target genes and could serve functionally as ‘oncogenes’ or ‘tumour suppressor’ genes, and co‐ordinate multiple cellular processes relevant to cancer progression. A number of studies have shown that miRNAs play important roles in breast tumorigenesis, metastasis, proliferation and differentiation of breast cancer cells. This review provides a comprehensive overview of miRNAs with established functional relevance in breast cancer, their established target genes and resulting cellular phenotype. The role and application of circulating miRNAs in breast cancer is also discussed. Furthermore, we summarize the role of miRNAs in the hallmarks of breast cancer, as well as the possibility of using miRNAs as potential biomarkers for detection of breast cancer.     

Regulation of cancer metastasis by microRNAs

MicroRNAs (miRNAs) are a class of endogenous small non-coding RNAs that have been found highly conserved among species. MiRNAs are able to negatively regulate gene expression through base pairing of 3’ UTRs of their target genes. Therefore, miRNAs have been shown to play an important role in regulating various cellular activities. Over the past decade, substantial evidences have been obtained to show that miRNAs are aberrantly expressed in human malignancies and could act as “OncomiRs” or “Tumor suppressor miRs”. In recent years, increasing number of studies have demonstrated the involvement of miRNAs in cancer metastasis. Many studies have shown that microRNAs could directly target genes playing a central role in epithelia-mesenchymal-transition (EMT), a cellular transformation process that allows cancer cells to acquire motility and invasiveness. EMT is considered an essential step driving the early phase of cancer metastasis. This review will summarize the recent findings and characterization of miRNAs that are involved in the regulation of EMT, migration, invasion and metastasis of cancer cells. Lastly, we will discuss potential use of miRNAs as diagnostic and prognostic biomarkers as well as therapeutic targets for cancer.     

A panel of three plasma microRNAs for colorectal cancer diagnosis

BackgroundDifferential microRNA (miRNA) expression profiles in plasma or serum were identified, providing foundation for studying their potentially diagnostic role in colorectal cancer (CRC).MethodsWe performed S-poly(T) Plus PCR assay to select and validate differentially expressed plasma miRNAs from a sample set including 101 CRC patients, 20 patients with colorectal noncancerous polyps (NCP), and 134 healthy controls. And bioinformatics methods was used to integrated predicted or validated targets of the differentially dysregulated miRNAs and analyzed their overrepresented pathways.ResultsAfter the two-phase selection and validation process, we identified a miRNA panel (miR-144-3p, miR-425-5p, and miR-1260b) with high diagnostic efficiency for CRC; the panel distinguished CRC patients from controls with 93.8% sensitivity and 91.3% specificity. Results indicated that the dysregulated miRNAs in CRC were functionally involved in several key cancer-related pathways, such as axonal guidance, PI3K, and calcium signaling pathways.ConclusionsOur study demonstrated that a plasma 3-miRNA panel may serve as a novel noninvasive biomarker to diagnose CRC. This plasma 3-miRNA panel may be related to CRC development. However, further studies are needed to highlight its theoretical strengths.     

High-sensitivity blood-based detection of breast cancer by multi photon detection diagnostic proteomics

We have developed several new methods for blood-based cancer detection by diagnostic proteomics. Ultrasensitive methods of immunoassay using multiphoton-detection (IA/MPD) increase sensitivity by 200- to 1,000-fold (1 femtogram/mL). This has allowed the measurement of cancer biomarkers with very low concentrations in blood that could not be measured for full patient cohorts with conventional immunoassays. Sensitivity and specificity in cancer detection have been found to be potentiated by use of immunoassay panels which include tissue-specific cancer biomarkers as well as cytokines and angiogenic factors. The ultrasensitive immunoassays revealed that patient to patient variations in the concentrations of individual biomarkers in blood can extend over many orders of magnitude (up to six) and that the distributions of biomarker concentrations over patient cohorts are non-Gaussian. New methods of data analysis which correlate abundances of multiple, different biomarkers have been developed to deal with such data sets. Sensitivity and specificity of about 95% have been achieved for blood-based detection of breast cancer in pilot studies on 250 patients and 95 controls. Pilot studies indicate that this methodology may also allow differentiation of malignant breast cancer from benign lesions and can provide similar sensitivity and specificity for other epithelial cancers such as prostate cancer, ovarian cancer and melanoma. The methods developed for selection, application, and evaluation of very high sensitivity biomarker panels are expected to have general relevance for diagnostic proteomics.