Circulating miR-148b and miR-133a as biomarkers for breast cancer detection

Circulating microRNAs have drawn a great deal of attention as promising novel biomarkers for breast cancer. However, to date, the results are mixed. Here, we performed a three-stage microRNA analysis using plasma samples from breast cancer patients and healthy controls, with efforts taken to address several pitfalls in detection techniques and study design observed in previous studies. In the discovery phase with 122 Caucasian study subjects, we identified 43 microRNAs differentially expressed between breast cancer cases and healthy controls. When those microRNAs were compared with published data from other studies, we identified three microRNAs, including miR-148b, miR-133a and miR-409-3p, whose plasma levels were significantly higher in breast cancer cases than healthy controls and were also significant in previous independent studies. In the validation phase with 50 breast cancer cases and 50 healthy controls, we validated the associations with breast cancer detection for miR-148b and miR-133a (P = 1.5×10⁻⁶ and 1.3×10⁻¹⁰, respectively). In the in-vitro study phase, we found that both miR-148b and miR-133a were secreted from breast cancer cell lines, showing their secretory potential and possible tumor origin. Thus, our data suggest that both miR-148b and miR-133a have potential use as biomarkers for breast cancer detection.     

Serum miR-21 and miR-92a as biomarkers in the diagnosis and prognosis of colorectal cancer

Previous studies from our laboratory identified a number of miRNAs that were aberrantly expressed in colorectal cancer (CRC) tissue. However, their diagnostic and prognostic value in serum has not been fully evaluated. In the present study, we measured the levels of five miRNAs (miR-21, miR-31, miR-92a, miR-18a, and miR-106a) in serum samples from 200 CRC patients, 50 advanced adenoma patients, and 80 healthy controls by real-time quantitative polymerase chain reaction (RT-PCR). In our study, the levels of miR-21 and miR-92a in patients with CRC and advanced adenoma were significantly higher than those in healthy controls (all P?<?0.05). MiR-21 yielded an area under the receiver-operating characteristics (ROC) curve (AUC) of 0.802 and miR-92a yielded an AUC of 0.786 in discriminating CRCs from the controls. Additionally, miR-21 and miR-92a yielded an AUC of 0.709 and 0.701, respectively, in discriminating advanced adenomas from the controls. Combined ROC analyses using both miRNAs, revealed an elevated AUC of 0.847 in discriminating CRCs, and an AUC of 0.722 in discriminating advanced adenomas from the controls. In the multivariate Cox proportional hazards analysis, high miR-92a expression in CRC was independently associated with poor survival (P?=?0.03; hazard ratio 4.36; 95 % confidence interval?=?1.64–11.57). No significant difference was observed in the levels of miR-18a, miR-31, and miR-106a among CRC, advanced adenoma, and control samples. In summary, our data indicate that miR-21 and miR-92a serum levels have potential value for early detection of CRC. Furthermore, miR-92a has prognostic value in CRC patients.     

Circulating cell-free miRNAs as biomarker for triple-negative breast cancer

Background:

Triple-negative breast cancer (TNBC) accounts for 15–20% of all breast cancer in women globally. This subtype often has early and high recurrence rates resulting in poor survival, partially due to lack of targeted therapies. Therefore, there is an urgent need to identify TNBC-specific biomarkers for early diagnosis and treatment monitoring, and to develop more effective targeted therapy.

Methods:

By using miRCURY LNA array platform, we compared the differential miRNA expressions in plasma of patient with TNBC (n=5) and non-TNBC (n=5), as well as healthy controls (n=5). Potential miRNAs were then validated in a large cohort of patients by real-time PCR.

Results:

Ten putative miRNAs from the microarray data that differentially expressed between non-TNBC and healthy controls were identified. In the screening phase (n=90), we selected five miRNAs (miR-92a-3p, miR-342-3p, miR-16, miR-21 and miR-199a-5p) that could discriminate TNBC from non-TNBC for further validation. Results showed that miR-16, miR-21 and miR-199a-5p were underexpressed in TNBC when compared with non-TNBC, and were further validated in a large cohort (n=252). In addition, post-operative plasma levels of miR-16, miR-21 and miR-199a-5p were significantly restored when compared with pre-operative plasma of TNBC. Plasma miR-199a-5p expression in TNBC had significant difference when compared with non-TNBC and healthy controls, the receiver-operator characteristics curve analysis revealed the highest area under curve (AUC=0.8838) among all. The expression levels were associated with TNM stage and tumour subtypes.

Conclusions:

Our data suggest that miR-199a-5p could be a TNBC-specific marker with diagnostic value and provide insights into targeted therapy in the treatment of TNBC.     

Differential expression of serum miR-126,miR-141 and miR-21 as novel biomarkers for early detection of liver metastasis in colorectal cancer简

Objective：MicroRNAs （miRNAs） have potential as diagnostic biomarkers in cancer.Evaluation of the association between miRNA expression patterns and early detection of liver metastasis in colorectal cancer （CRC） has not been reported.Methods：We investigated the expression of metastasis-associated miRs-31,335,206,141,126,200b,200c,21,Let7a,Let7b and Let7c in localized,liver-metastatic and other organ-metastatic CRC （OM-CRC）.Expressions of target miRNAs in serum were evaluated in 116 consecutive localized CRC （L-CRC）,72 synchronous liver-metastatic CRC （SLM-CRC） and 36 other OM-CRC by quantitative real-time PCR.Results：Seven of 11 tested miRNAs could be detected from serum.Four miRNAs,miR-126,Let-7a,miR141 and miR-21 were identified as metastasis-associated miRNAs.Compared with L-CRC,significant upregulated expression was observed for miR-141 and miR-21 in SLM-CRC and OM-CRC,down-regulated expression was observed for miR-126 in SLM-CRC and OM-CRC,and up-regulated expression of Let-7a in OM-CRC.The receiver operating characteristic （ROC） curve showed serum miR-126 had a cut-off [log10 relative quantity （log10RQ）=--0.2005] with 77.78％ sensitivity and 68.97％ specificity with an area under curve （AUC） of 0.7564,miR-141 had a cut-off （1og10RQ=-0.2285） with 86.11％ sensitivity and 76.11％ specificity with an AUC of 0.8279,and miR-21 had a cut-off （log10RQ=-0.1310） with 73.61％ sensitivity and 66.38％ specificity with an AUC of 0.7479.Conclusions：We identified liver metastasis-associated miRNAs,suggesting serum miR-126,miR-141 and miR-21 may be novel biomarkers for clinical diagnosis of early stage liver-metastatic CRC.     

肺癌转移相关microRNA miR-29b的生物信息学分析*

目的: 应用生物信息学分析A549细胞中在CD133阳性低表达的miR-29b的靶基因及其功能,为以miR-29b为靶点的肿瘤研究提供线索。 方法: 利用miRNA PCR芯片筛选A549细胞中CD133阳性和CD133阴性差异表达的miRNA,选用miRecords预测miR-29b的靶基因,合并已证实的靶基因,利用GOEAST和DAVID数据库对所得靶基因进行功能富集分析和信号转导通路富集分析。 结果: A549细胞中与CD133阴性比较,miR-29b在CD133阳性中表达下调。miR-29b靶基因有106个,其靶基因功能富集于结合和细胞外基质形成等作用（P<0.01）;信号转导通路显著富集于JAK-STAT和TGF-β等信号转导通路（P<0.05）。 结论: miR-29b可能与肺癌转移相关,miR-29b的靶基因显著富集在与肿瘤相关的信号通路中。      

Circulating miR-378 in plasma: a reliable,haemolysis-independent biomarker for colorectal cancer

Background:

Plasma circulating tumour-specific microRNAs (miRNAs) are promising biomarkers of tumour presence and recurrence, especially for diseases whose best chance of successful treatment requires early diagnosis and timely surgery of an already malignant but not yet invasive tumour, such as colorectal cancer (CRC).

Methods:

Expression levels of miRNAs previously found to be differently expressed in tumour vs normal colon tissues were investigated by quantitative real-time PCR in plasma from CRC patients and from healthy donors and confirmed in independent case control series. The validated miRNAs were also measured after surgery. Analyses were repeated on the subsets of haemolysis-free samples.

Results:

We identified four miRNAs differently expressed between the compared groups, two (miR-21 and miR-378) of which were validated. miR-378 expression decreased in non-relapsed patients 4–6 months after surgery and miR-378 ability to discriminate CRC patients from healthy individuals was not influenced by haemolysis levels of plasma samples.

Conclusion:

The miRNA analysis on plasma samples represents a useful non-invasive tool to assess CRC presence as well as tumour-free status at follow-up. Plasma levels of miR-378 could be used to discriminate CRC patients from healthy individuals, irrespective of the level of haemoglobin of plasma samples.     

Circulating microRNAs as potential new biomarkers for prostate cancer

Since they were first described in the 1990s, circulating microRNAs (miRNAs) have provided an active and rapidly evolving area of current research that has the potential to transform cancer diagnostics and therapeutics. In particular, miRNAs could provide potential new biomarkers for prostate cancer, the most common cause of cancer in UK men. Current diagnostic tests for prostate cancer have low specificity and poor sensitivity. Further, although many prostate cancers are so slow growing as not to pose a major risk to health, there is currently no test to distinguish between these and cancers that will become aggressive and life threatening. Circulating miRNAs are highly stable and are both detectable and quantifiable in a range of accessible bio fluids, thus have the potential to be useful diagnostic, prognostic and predictive biomarkers. This review aims to summarise the current understanding of circulating miRNAs in prostate cancer patients and their potential role as biomarkers.     

Circulating tumour cells and circulating free nucleic acid as prognostic and predictive biomarkers in colorectal cancer

The detection of circulating tumour cells or circulating free tumour nucleic acids can potentially guide treatment and inform prognosis in colorectal cancer using minimally invasive “liquid biopsies”. Current literature supports the notion that high circulating tumour cell counts or presence of tumour nucleic acid correlate with inferior clinical outcomes for patients, but they are not yet part of routine clinical care. Future research evolves around the examination of the molecular phenotype of circulating tumour cells. The key unanswered areas include differentiating between circulating tumour cell presence and their proliferative capacity and dormancy, identifying tumour heterogeneity and understanding the epithelial–mesenchymal transition.     

血清中miR-29a和miR-92a在结直肠癌诊断和预后判断中的价值

目的探讨血清微小RNA（miR-29a和miR-92a）在结直肠癌（CRC）诊断和预后判断中的价值。方法选取无转移的结直肠癌患者50例和存在肝转移的患者48例,同时募集50名健康志愿者为对照组,按类似的年龄和性别相匹配的队列组合。应用实时荧光定量聚合酶链反应（PCR）法检测微小RNA（miR-29a和miR-92a）水平,判断该血清微小RNA在结直肠癌早期诊断和预后判断中的价值。结果结直肠癌患者血清中miR-29a和miR-92a水平均显著高于健康对照者（P〈0.01）;血清miR-29a和miR-92a分别进行结直肠癌诊断时的灵敏度为71.4%和75.3%,特异度为84.0%和88.3%;结直肠癌肝转移患者血清中miR-29a和miR-92a水平均显著高于未转移的CRC患者（P〈0.05）;miR-29a和miR-92a分别鉴别转移性与非转移性CRC患者的敏感性为79.4%和78.6%,特异性为85.3%和86.6%。结论 miR-29a和miR-92a可能是新的非侵入性指标用于结直肠癌患者的早期诊断,血清中miR-29a和miR-92a水平升高与结直肠癌患者预后有关,miR-29a和miR-92a有望成为结直肠癌筛查和早期诊断和预后判断的指标。     

Epigenetically silenced miR-34b/c as a novel faecal-based screening marker for colorectal cancer

Background:

MicroRNAs are tiny non-coding small endogenous RNAs that regulate gene expression by translational repression, mRNA cleavage and mRNA inhibition. The aim of this study was to investigate the hypermethylation of miR-34b/c and miR-148a in colorectal cancer, and correlate this data to clinicopathological features. We also aimed to evaluate the hypermethylation of miR-34b/c in faeces specimens as a novel non-invasive faecal-DNA-based screening marker.

Methods:

The 5-aza-2′-deoxycytidine treatment and methylation-specific PCR were carried out to detect the hypermethylation of miR-34b/c and miR-148a.

Results:

The miR-34b/c hypermethylation was found in 97.5% (79 out of 82) of primary colorectal tumours, P=0.0110. In 75% (21 out of 28) of faecal specimens we found a hypermethylation of miR-34b/c while only in 16% (2 out of 12) of high-grade dysplasia. In addition, miR-148a was found to be hypermethylated in 65% (51 out of 78) of colorectal tumour tissues with no significant correlation to clinicopathological features. However, a trend with female gender and advanced age was found, P=0.083. We also observed a trend to lower survival rate in patients with miR-148a hypermethylation with 10-year survival probability: 48 vs 65%, P=0.561.

Conclusions:

These findings show that aberrant hypermethylation of miR-34b/c could be an ideal class of early screening marker, whereas miR-148a could serve as a disease progression follow-up marker.     

miR-30b对结直肠癌细胞转移潜能的影响

  目的   明确miR-30b对结直肠癌细胞侵袭和迁移潜能的影响。   方法   RT-qPCR检测20对配对结直肠癌组织标本中miR-30b的表达;Transwell和划痕实验检测过表达和抑制miR-30b后结直肠癌细胞侵袭和迁移潜能的改变;应用生物信息学方法预测miR-30b的作用靶点;Western Blot及双荧光素酶报告基因实验验证过表达和抑制miR-30b后靶点Snail和EMT（epithelial mesenchymal transition）标志物的表达情况。   结果   癌组织中miR-30b表达水平明显低于正常肠黏膜组织;Transwell及划痕实验结果显示过表达miR-30b后结直肠癌细胞的侵袭迁移能力降低,抑制miR-30b后侵袭迁移能力增强;生物信息学预测结果显示miR-30b能够作用于Snail 3'-UTR,双荧光素酶检测结果进一步证实miR-30b能够作用于Snail 3'-UTR;Western Blot结果显示过表达miR-30b后Snail的表达下降,EMT标志物Vimentin表达下降和E-cadherin表达升高,而抑制miR-30b后结果相反。   结论   miR-30b在结直肠癌中表达水平下降,并通过靶向Snail调节结直肠癌细胞的侵袭和迁移。      

外泌体作为结直肠癌诊断标志物的研究进展

外泌体是一种由细胞分泌至胞外的直径为30~150 nm的纳米囊泡,广泛分布于人体血液、尿液、唾液、汗液、乳汁和脑脊液等多种体液中。结直肠癌是常见的消化道恶性肿瘤,其发病率在全球范围内位居第三,严重威胁着人类健康。结直肠癌来源的外泌体中含有一些肿瘤特异性蛋白、微小RNAs（microRNAs,miRNAs）和长链非编码 RNAs（long non-coding RNAs,lncRNAs）等,与结直肠癌的发生和发展具有相关性,因此有望作为结直肠癌诊断的生物标志物。本文主要对外泌体在结直肠癌诊断中的应用前景作一综述。     

结直肠癌中医辨证分型与miR-29、miR-34a表达的相关性分析

目的:探究结直肠癌患者血清miR-29、miR-34a表达水平及其与中医辨证分型的相关性。方法:选取2014年06月至2015年06月本院收治的127例结直肠癌患者作为研究对象（结直肠癌组）,并根据中医辨证分型标准分为湿热内蕴型21例、气滞血瘀型40例、脾肾阳虚型29例、气血两虚型18例、肝肾阴虚型19例;另选取同期在本院体检的127例健康者作为健康对照组。采用实时荧光定量PCR（qRT-PCR）技术检测血清miR-29、miR-34a表达水平,并进行比较;采用Pearson法分析血清miR-29与miR-34a表达水平的相关性;采用Logistic回归模型分析影响结直肠癌患者不良预后发生的危险因素。结果:结直肠癌组患者血清miR-29、miR-34a表达水平均明显低于健康对照组（P＜0.05）。低分化、浸润程度T3-T4、TNM分期Ⅲ-Ⅳ期、淋巴结转移、远处转移患者血清miR-29、miR-34a表达水平明显低于高中分化、浸润程度T1-T2、TNM分期Ⅰ-Ⅱ期、无淋巴结转移、无远处转移患者（P＜0.05）。结直肠癌患者血清miR-29与miR-34a表达水平呈正相关（r=0.529,P=0.000）。低分化、浸润程度T3-T4、TNM分期Ⅲ-Ⅳ期、淋巴结转移、低miR-29水平、低miR-34a水平是影响结直肠癌患者不良预后发生的危险因素（P＜0.05）。脾肾阳虚型、气滞血瘀型、湿热内蕴型预后不良患者比例依次明显增加（P＜0.05）。肝肾阴虚型、气血两虚型、脾肾阳虚型、气滞血瘀型、湿热内蕴型结直肠癌患者血清miR-34a表达水平依次显著降低（P＜0.05）,miR-29表达水平差异无统计学意义（P＞0.05）。结论:结直肠癌患者血清中miR-29、miR-34a低表达,与肿瘤分期升高、分化程度降低、浸润程度增加、淋巴结转移、远处转移、不良预后等密切相关,且miR-34a对结直肠癌不同中医辨证分型有一定的分型参考意义。     

Cell-free microRNAs as cancer biomarkers: the odyssey of miRNAs through body fluids

Cell-free microRNAs (cfmiRNAs), also known as extracellular or secretory microRNAs, are an emerging class of miRNAs that are released or secreted by cells. These miRNAs are transferred through various body fluids. A growing body of research has recently revealed that cancer cells also secrete their distinctive cfmiRNAs to the extracellular environment highlighting the contribution of cfmiRNAs to cancer progression. CfmiRNAs show high stability in the body fluids. Three pathways have been proposed for their entry into the body fluids: passive release from broken, injured and dead cells; active secretion through microvesicles; and active secretion via microvesicle-free protein-dependent route. Active pathways seem to play leading roles in the delivery of miRNAs. Detection of cfmiRNAs is of particular relevance to their translation into the clinic. Much effort has been devoted to the development of highly sensitive and efficient approaches for detection purposes. Nevertheless, some barriers such as finding a unique internal control for all cancer types remain to be bypassed. This review aims to provide an insight into the promises represented by cfmiRNAs as cancer biomarkers and describes advances made in the identification of numerous types of extracellular miRNAs that have potential for use in the diagnosis of a variety of cancers.     

MicroRNAs as diagnostic and prognostic biomarkers in colorectal cancer

MicroRNAs (miRNAs) are key regulators involved in various tumors. They regulate cell cycle, apoptosis and cancer stemness, metastasis and chemoresistance by controlling their target gene expressions. Here, we mainly discuss the potential uses of miRNAs in colorectal cancer (CRC) diagnosis. We also shed light on the important corresponding miRNA targets and on the major regulators of miRNAs. Furthermore, we discuss miRNA activity in assessing the prognosis and recurrence of CRC as well as in modulating responsiveness to chemotherapy. Based on the various pro-oncogenic/anti-oncogenic roles of miRNAs, the advantages of a therapeutic strategy based on the delivery of miRNA mimics are also mentioned. Together, miRNA seems to be an excellent tool for effectively monitoring and targeting CRC.     

Circulating biomarkers for detection of ovarian cancer and predicting cancer outcomes

Background:

Securing a diagnosis of ovarian cancer and establishing means to predict outcomes to therapeutics remain formidable clinical challenges. Early diagnosis is particularly important since survival rates are markedly improved if tumour is detected early.

Methods:

Comprehensive miRNA profiles were generated on presurgical plasma samples from 42 women with confirmed serous epithelial ovarian cancer, 36 women diagnosed with a benign neoplasm, and 23 comparably age-matched women with no known pelvic mass.

Results:

Twenty-two miRNAs were differentially expressed between healthy controls and the ovarian cancer group (P<0.05), while a six miRNA profile subset distinguished presurgical plasma from benign and ovarian cancer patients. There were also significant differences in miRNA profiles in presurgical plasma from women diagnosed with ovarian cancer who had short overall survival when compared to women with long overall survival (P<0.05).

Conclusion:

Our preliminary data support the utility of circulating plasma miRNAs to distinguish women with ovarian cancer from those with a benign mass and identify women likely to benefit from currently available treatment for serous epithelial ovarian cancer from those who may not.     

结肠癌中miR-135b、miR-141的检测意义

目的 探讨miR-135b、miR-141在结肠癌中的表达以及与肿瘤临床特征之间的相关性。方法 分析2013年2月—2014年5月在上海市闸北区市北医院普通外科接受手术治疗切除的结肠癌及正常结肠组织标本。比较结肠癌与正常结肠组织的miR-135b、miR-141表达差异,并探讨在结肠癌中miR-135b、miR-141的表达与其临床特征的相关性。结果 本研究共纳入结肠癌患者42例和正常结肠组织标本42例。结肠癌组织的miR-135b、miR-141表达均显著高于正常结肠组织(P＜0.01);不同的Dukes分期、分化程度、淋巴结转移情况以及浸润深度所对应的结肠癌组织的miR-135b表达之间的差异均具有统计学意义(P＜0.05);不同的Dukes分期、分化程度、淋巴结转移情况以及浸润深度所对应的结肠癌组织的miR-141表达之间的差异均具有统计学意义(P＜0.05);miR-135b与miR-141的表达水平呈正相关(r=0.611,P=0.023)。结论 miR-135b、miR-141与结肠癌的发生、发展有着密切的联系。