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Simple Summary Liquid biopsies seek to isolate tumor derived genetic material that circulates in blood plasma or cerebrospinal fluid. The less-invasive character of liquid biopsies combined with the option for serial analyses bears enormous potential for treatment monitoring or surveillance. We aimed to establish robust sampling protocols and pre-analytical workflows to allow for site independent multi-layer liquid biopsy testing. For an optimal usage of precious material, we explored sample stabilization in various conservation tubes and describe a protocol for the parallel isolation of cell-free DNA and RNA. Quantification and quality control steps were optimized for minimal sample use with both high sensitivity and reproducibility. We provide detailed step-by-step information on how to i) choose the best-suited protocol and ii) implement this in the liquid biopsy workflow. We believe that our study has potential to increase comparability of liquid biopsy approaches to bring these one step closer to routine clinical application. Abstract Liquid biopsies hold great promise for the management of cancer. Reliable liquid biopsy data depend on stable and reproducible pre-analytical protocols that comply with quality measures, irrespective of the sampling and processing site. We established a workflow for plasma preservation, followed by processing, cell-free nucleic acid isolation, quantification, and enrichment of potentially tumor-derived cell-free DNA and RNA. Employing the same input material for a direct comparison of different kits and protocols allowed us to formulate unbiased recommendations for sample collection, storage, and processing. The presented workflow integrates the stabilization in Norgen, PAX, or Streck tubes and subsequent parallel isolation of cell-free DNA and RNA with NucleoSnap and NucleoSpin. Qubit, Bioanalyzer, and TapeStation quantification and quality control steps were optimized for minimal sample use and high sensitivity and reproducibility. We show the efficiency of the proposed workflow by successful droplet digital PCR amplification of both cell-free DNA and RNA and by detection of tumor-specific alterations in low-coverage whole-genome sequencing and DNA methylation profiling of plasma-derived cell-free DNA. For the first time, we demonstrated successful parallel extraction of cell-free DNA and RNA from plasma samples. This workflow paves the road towards multi-layer genomic analysis from one single liquid biopsy sample.

Nucleic acids include two main classes: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) [...]

Despite advances in automated liquid handling and microfluidics, preparing samples for RNA sequencing at scale generally requires expensive equipment, which is beyond the reach of many academic labs. Manual sample preparation remains a slow, expensive, and error-prone process. Here, we describe a low-cost, semi-automated pipeline to extract cell-free RNA (cfRNA) that like many RNA isolation protocols, can be decomposed into three subparts – RNA extraction, DNA digestion, and RNA cleaning and concentration. RT-qPCR data using a synthetic spike-in confirms comparable RNA quality as compared to manual sample processing, the gold-standard used in our prior work. The semi-automated pipeline also shows striking improvement in sample throughput (+12x), time spent (−11x), cost (−3x), and biohazardous waste produced (−4x) as compared to its manual counterpart. In total, this protocol enables cfRNA extraction from 96 samples simultaneously in 4.5 hours; in practice, this dramatically improves time to results as demonstrated in our recent work [1] where it was used to process 404 samples in 27 hours. Importantly, any lab already has most of the parts required (manual pipette, corresponding tips and kits) to build a semi-automated sample processing pipeline of their own and would only need to purchase or 3D-print a few extra parts ($5.5K total). This pipeline is also generalizable for many nucleic acid extraction applications, thereby increasing the scale of studies, which can be performed in small research labs.

Neurological diseases are responsible for approximately 6.8 million deaths every year. They affect up to 1 billion people worldwide and cause significant disability and reduced quality of life. In most neurological disorders, the diagnosis can be challenging; it frequently requires long-term investigation. Thus, the discovery of better diagnostic methods to help in the accurate and fast diagnosis of neurological disorders is crucial. Circulating nucleic acids (CNAs) are defined as any type of DNA or RNA that is present in body biofluids. They can be found within extracellular vesicles or as cell-free DNA and RNA. Currently, CNAs are being explored as potential biomarkers for diseases because they can be obtained using non-invasive methods and may reflect unique characteristics of the biological processes involved in several diseases. CNAs can be especially useful as biomarkers for conditions that involve organs or structures that are difficult to assess, such as the central nervous system. This review presents a critical assessment of the most current literature about the use of plasma and serum CNAs as biomarkers for several aspects of neurological disorders: defining a diagnosis, establishing a prognosis, and monitoring the disease progression and response to therapy. We explored the biological origin, types, and general mechanisms involved in the generation of CNAs in physiological and pathological processes, with specific attention to neurological disorders. In addition, we present some of the future applications of CNAs as non-invasive biomarkers for these diseases.

SummaryHuman plasma contains >40,000 different coding and non-coding RNAs that are potential biomarkers for human diseases. Here, we used thermostable group II intron reverse transcriptase sequencing (TGIRT-seq) combined with peak calling to simultaneously profile all RNA biotypes in apheresis-prepared human plasma pooled from healthy individuals. Extending previous TGIRT-seq analysis, we found that human plasma contains largely fragmented mRNAs from >19,000 protein-coding genes, abundant full-length, mature tRNAs and other structured small non-coding RNAs, and less abundant tRNA fragments and mature and pre-miRNAs. Many of the mRNA fragments identified by peak calling correspond to annotated protein-binding sites and/or have stable predicted secondary structures that could afford protection from plasma nucleases. Peak calling also identified novel repeat RNAs, miRNA-sized RNAs, and putatively structured intron RNAs of potential biological, evolutionary, and biomarker significance, including a family of full-length excised introns RNAs, subsets of which correspond to mirtron pre-miRNAs or agotrons.

Urothelial carcinoma of the bladder (UCB) is a common cancer worldwide with over 430,000 new cases in 2012 and 165,000 deaths and is currently the most expensive cancer per capita to treat in the U...

The rapid and accurate diagnosis of patients with minimally invasive procedures was once only found in science fiction. However, the discovery of extracellular vesicles (EVs) and their near ubiquity in body fluids, coupled with the advent of inexpensive next generation sequencing techniques and EV purification protocols, promises to make science fiction a reality. Purifying and sequencing the RNA content of EV from routine blood draws and urine samples are likely to enable pathologists and physicians to diagnose and track the progress of diseases in many inaccessible tissues in the near future. Here we present the evolutionary background of EV, summarize the biology of EV formation and cargo selection, and discuss the current barriers to making continuous liquid biopsies through the use of EV a science reality.

Nucleic acids in circulation, called cell free DNA (cfDNA) and cell free RNA (cfRNA), have recently been analyzed as suitable diagnostic and prognostic markers in cancer. There have also been several reports about the role of this type of marker in leukemia. The relevant literature was identified by a PubMed search (2000–2017) of English-language literature using the terms “cell free DNA”, “Leukemia” and Micro-RNA. Many quantitative and qualitative cfDNA biomarkers including copy number alteration, mutation, LOH and micro-RNA deregulated expression have been investigated in different studies, indicating promising results to distinguish patients from healthy individuals. The findings of this study indicate that nucleic acids in circulation have a high diagnostic and prognostic value in leukemic patients and, thus, have the potential to be used alongside the usual methods in the management of this disease.

Background The amniotic fluid (AF) cell-free transcriptome is modulated by physiologic and pathologic processes during pregnancy. AF gene expression changes with advancing gestation reflect fetal development and organ maturation; yet, defining normal expression and splicing patterns for biomarker discovery in obstetrics requires larger heterogeneous cohorts, evaluation of potential confounding factors, and novel analytical approaches. Methods Women with a normal pregnancy who had an AF sample collected during midtrimester (n = 30) or at term gestation (n = 68) were included. Expression profiling at exon level resolution was performed using Human Transcriptome Arrays. Differential expression was based on moderated t-test adjusted p 1.25; for differential splicing, a splicing index > 2 and adjusted p In-silico validation studies were performed using publicly available datasets. Results 1) 64,071 genes were detected in AF, with 11% of the coding and 6% of the non-coding genes being differentially expressed between midtrimester and term gestation. Expression changes were highly correlated with those previously reported (R > 0.79, p p Conclusions This represents the largest AF transcriptomics study in normal pregnancy, reporting for the first time that single-cell genomic signatures can be tracked in the AF and display complex patterns of expression during gestation. We also demonstrate a role for alternative splicing in tissue-identity acquisition, organ development, and immune processes. The results herein may have implications for the development of fetal testing to assess placental function and fetal organ maturity.

Extracellular RNA s (exRNA s) in biofluids have attracted great interest as potential biomarkers. Although extracellular microRNA s in blood plasma are extensively characterized, extracellular messenger RNA (mRNA ) and long non‐coding RNA (lncRNA ) studies are limited. We report that plasma contains fragmented mRNA s and lncRNA s that are missed by standard small RNA ‐seq protocols due to lack of 5′ phosphate or presence of 3′ phosphate. These fragments were revealed using a modified protocol (“phospho‐RNA ‐seq”) incorporating RNA treatment with T4‐polynucleotide kinase, which we compared with standard small RNA ‐seq for sequencing synthetic RNA s with varied 5′ and 3′ ends, as well as human plasma exRNA . Analyzing phospho‐RNA ‐seq data using a custom, high‐stringency bioinformatic pipeline, we identified mRNA /lncRNA transcriptome fingerprints in plasma, including tissue‐specific gene sets. In a longitudinal study of hematopoietic stem cell transplant patients, bone marrow‐ and liver‐enriched exRNA genes were tracked with bone marrow recovery and liver injury, respectively, providing proof‐of‐concept validation as a biomarker approach. By enabling access to an unexplored realm of mRNA and lncRNA fragments, phospho‐RNA ‐seq opens up new possibilities for plasma transcriptomic biomarker development., We acknowledge funding support from the NIH Extracellular RNA Communication Common Fund grants: U01 grants HL126499 to M. Tewari and HL126496 to D.J.G., and from the A. Alfred Taubman Medical Research Institute (Grand Challenge Award) to M. Tewari and S.W.C. Research reported in this publication was also supported by the National Cancer Institute of the NIH under Award Number P30CA046592 by the use of the following Cancer Center Shared Resource at the University of Michigan: DNA Sequencing. M.D.G. acknowledges support from a Precision Health Scholar Award from the University of Michigan Precision Health Center and a Juan Rodes contract (JR18/00026) funded by the Spanish Institute of Health Carlos III from the Ministry of Economy and Competitiveness (co‐funded by European Social Fund (ESF)). D.J.G. also acknowledges a special technology support award and partial funding from the Pacific Northwest Research Institute to his laboratory.

// Dan Zhou 1, 2 , Weiwei Tang 1 , Xinli Liu 1 , Han-Xiang An 1 and Yun Zhang 1, 2 1 Department of Medical Oncology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China 2 Xiamen Institute of Rare Earth Materials, Chinese Academy of Sciences and Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Xiamen, Fujian, China Correspondence to: Yun Zhang, email: zhangy@fjirsm.ac.cn Han-Xiang An, email: anhanxiang@xmu.edu.cn Keywords: lung cancer, biomarker, cell-free RNA, HJURP, ADAMTS8 Received: November 30, 2016 Accepted: March 08, 2017 Published: March 30, 2017 ABSTRACT Lung cancer (LC) remains associated with significant mortality worldwide. The lack of reliable noninvasive biomarkers and targeted therapies contributes to poor survival rate. Herein, we initially took advantage of the public microarray data from Oncomine database to filter messenger RNAs (mRNAs) as potential biomarkers. Subsequently, clinical validation was applied to identify candidate noninvasive biomarkers in plasma from patients with LC. Through comprehensive analysis of transcriptional expression profiles across 12 studies, top 6 over- and underexpressed mRNAs were generated. Then, a pair of matched plasma samples from LC patient and normal control was detected by RT-PCR, and three genes with positive bands were selected for further validation. Finally, qPCR was conducted to further assess values of the three identified genes. We displayed with high confidence that two cell-free mRNAs (HJURP and ADAMTS8) were expressed at significantly levels compared to normal controls. Receiver-operating characteristic (ROC) curves on the diagnostic efficacy of plasma HJURP and ADAMTS8 mRNAs in LC diagnosis showed that the area under the ROC (AUC) was 0.6960 and 0.6877; sensitivity was 66.0% and 83.7%; specificity was 78.6% and 71.4%, respectively. Combined ROC analyses using these two biomarkers revealed an elevated AUC of 0.75. Furthermore, the higher HJURP level could be associated with early-stage LC while lower ADAMTS8 level could be correlated with non-small cell lung cancer. Collectively, circulating HJURP and ADAMTS8 mRNAs are promising noninvasive biomarkers for LC diagnosis. Our integrative strategy provides new insights into novel noninvasive biomarker identification for other types of cancer.

Cell-free nucleic acids (cf-NAs) originate in trophoblasts and are detected in the maternal plasma. Using innovative bioinformatic technologies such...

The immune system has evolved to protect multicellular organisms from the attack of a variety of pathogens. To exert this function efficiently, the system has developed the capacity to coordinate the function of different cell types and the ability to down-modulate the response when the foreign attack is over. For decades, immunologists believed that these two characteristics were primarily related to cytokine/chemokine-based communication and cell-to-cell direct contact. More recently, it has been shown that immune cells also communicate by transferring regulatory RNAs, microRNAs in particular, from one cell to the other. Several studies have suggested a functional role of extracellular regulatory RNAs in cell-to-cell communication in different cellular contexts. This minireview focuses on the potential role of extracellular RNA transfer in the regulation of adaptive immune response, also contextualizing it in a broader field of what is known of cell-free RNAs in communication among different organisms in the evolutionary scale.

Extracellular RNAs present in biofluids have emerged as potential biomarkers for disease. Where most studies focus on plasma or serum, other biofluids may contain more informative RNA molecules, depending on the type of disease. Here, we present an unprecedented atlas of messenger, circular and small RNA transcriptomes of a comprehensive collection of 20 different human biofluids. By means of synthetic spike-in controls, we compared RNA content across biofluids, revealing a more than 10 000-fold difference in RNA concentration. The circular RNA fraction is increased in nearly all biofluids compared to tissues. Each biofluid transcriptome is enriched for RNA molecules derived from specific tissues and cell types. In addition, a subset of biofluids, including stool, sweat, saliva and sputum, contains high levels of bacterial RNAs. Our atlas enables a more informed selection of the most relevant biofluid to monitor particular diseases. To verify the biomarker potential in these biofluids, four validation cohorts representing a broad spectrum of diseases were profiled, revealing numerous differential RNAs between case and control subjects. Taken together, our results reveal novel insights in the RNA content of human biofluids and may serve as a valuable resource for future biomarker studies. All spike-normalized data is publicly available in the R2 web portal and serve as a basis to further explore the RNA content in biofluids.

The combined analysis of circulating cell-free (tumor) DNA (cfDNA/ctDNA) and circulating cell-free (tumor) RNA (cfRNA/ctRNA) shows great promise in determining the molecular profile of cancer patients. Optimization of the workflow is necessary to achieve consistent and reproducible results. In this study, we compared five centrifugation protocols for the optimal yield of both cfDNA/ctDNA and cfRNA/ctRNA. These protocols varied in centrifugation speed, ambient temperature, time, and number of centrifugation steps. Samples from 33 participants were collected in either BD Vacutainer K2EDTA (EDTA) tubes or cell-free DNA BCT&reg, (Streck) tubes. cfDNA concentration and fragment size, and cfRNA concentration were quantitated in all samples by digital droplet PCR (ddPCR) and quantitative PCR (qPCR). The KRAS-mutated ctDNA and ctRNA fraction was determined via ddPCR. In EDTA tubes, the protocol generating both plasma and platelets was found to produce high quality cfDNA and cfRNA concentrations. Two-step, high-speed centrifugation protocols were associated with high cfDNA but low cfRNA concentrations. High cfRNA concentrations were generated by a one-step, low-speed protocol. However, this coincided with a high amount of genomic DNA (gDNA) contamination. In Streck tubes, two-step, high-speed centrifugation protocols also generated good quality, high cfDNA concentration. However, these tubes are not compatible with cfRNA analysis.

INTRODUCTION: Glioblastoma (GBM) is a malignant primary brain tumour with dismal prognosis. Treatment monitoring remains a challenge in clinical routine, since brain imaging cannot reliably differentiate between true progression and treatment-associated changes. In this project, we evaluate different methods of extracellular vesicles (EV) purification, in order to specifically isolate GBM-EVs from human serum/plasma and introduce EVs, as well as cell-free RNA as possible biomarkers for treatment monitoring in GBM patients. METHODS: EVs from primary GBM cells and the Gaussia luciferase expressing Gli36-GLuc cells were isolated via size-exclusion chromatography (SEC) and ultracentrifugation. EV-surface markers were evaluated by flow cytometry. Gli36-GLuc EVs containing GLuc mRNA were spiked in healthy plasma. Thereafter, plasma EVs were isolated via ultracentrifugation, SEC and immunoprecipitation. Subsequently, RNA was isolated from vesicles and evaluated for GLuc levels via qRT-PCR. Total cell-free RNA from serum of GBM patients was tested for different mRNAs and micro-RNAs at different disease stages. RESULTS: EVs from GBM cells expressed high levels of CD29 and CD44, when compared to EVs from healthy donor plasma. Gli36-GLuc EVs spiked in healthy plasma were more effectively isolated with CD44-based immunoprecipitation than with ultracentrifugation or SEC, as shown by higher GLuc RNA levels in the corresponding vesicles. When compared to total cell-free RNA extracted from this plasma, RNA from EVs exhibited a higher GLuc yield. In cell-free RNA from GBM patients, MGMT levels alone were not capable of detecting progressive disease. CONCLUSIONS: 1. CD44 could serve as a novel, promising target for GBM-EV and be utilised for immunoprecipitation-based EV capturing. 2. Using the appropriate EV purification method possibly affects their potential as biomarkers for GBM. 3. MGMT levels alone in cell-free RNA of GBM patients did not correlate with disease status contrary to previous reports.

Genetic disorders are quite a major topic of discussion and debate in the recent world of biological sciences. Turner’s syndrome is one such disorder caused by a chromosome aneuploidy and it has characteristic symptoms in the patient or the affected individual. The amniotic fluid is a complex biological material found in the amniotic sac of pregnant women and they can provide valuable knowledge and understanding of the pathogenesis of this particular chromosomal abnormality. In this study, global gene expression analysis of cell-free RNA in amniotic fluid supernatant was used to detect genes/organ systems which may be significant in the pathophysiology of Turner’s syndrome. The cell-free RNA from the amniotic fluid of five mid-trimester Turner’s syndrome fetuses and five euploid female fetuses matched for age of gestation were extracted, amplified and hybridized onto Affymetrix U33 Plus 2.0. array. The paired t-test was used to identify the significantly differentially regulated genes. Biological interpretation was conducted using ingenuity pathway analysis and BioGPS gene expression atlas. Of the genes, XIST was especially downregulated and SHOX was not expressed differentially. One of the most highly represented organ systems was the hematologic/immune system, differentiating the transcriptome of Turner’s syndrome from other chromosomal aneuploidies that are discussed in this area of science. The differences in the transcriptome of the Turner’s syndrome are due to genome-wide dysregulation. The hematologic/immune system differences are significant in early-onset autoimmune dysfunction. There are other genes which have been identified that are associated with the cardiovascular and the skeletal system, as these are often seen to be affected in the female patients with turner’s syndrome. Hopefully, such knowledge gained from this study will help us to understand the deeper mechanisms of this disorder and the possible treatments of this disease.

Cancer and fetal development share a lot. This is nothing new. The 19th century pathologist John Beard noted the similarities between a tumor and a trophoblast. Building on that, Lloyd Old, a pioneer in cancer immunology said, “If you've ever seen the trophoblast invading the uterus, it invades, spreads, creates a blood supply. It also suppresses the maternal immune system. All of those are characteristics of cancer” (1). Today, tumors are being diagnosed noninvasively through the ability to find traces of circulating malignant material in blood. The same holds true for fetal development. The ability to reliably detect fetal cell-free DNA in maternal blood is changing clinical practice. I spoke with Howard Hughes Investigator and bioengineering, physics, and applied physics professor at Stanford University, Stephen Quake, who has played a central role in these innovations. Motivated to replace invasive biopsies with blood tests, Quake developed a polymorphism-independent shotgun DNA sequencing test that could detect fetal aneuploidy from maternal plasma (2). “After 10 years, this has had an enormous impact,” he says, “three million women are tested each year, and these methods have been widely adopted in the liquid biopsy space.” Quake has his sights on another challenge around childbirth—estimating gestational age and the risk for preterm delivery. “It started with the idea of following human development, and using RNA to do that,” Quake explains. In a manuscript in which he and colleagues combined high-throughput microarrays for RNA analysis with next-generation sequencing …

There is limited research on cell-free RNA (cf-RNA) in the urine of cancer patients. The present study was performed to detect the cf-RNA in the urine of patients with clear cell renal cell carcinoma (ccRCC). Ninety-five urine samples from ccRCC patients and 50 urine samples from control subjects were analyzed. The cf-RNA integrity index was calculated by using quantitative real-time RT-PCR assays of the small-sized fragment (106 bp) and the big-sized fragment (416 bp) in GAPDH mRNA. The initial analysis showed that cf-RNA was stable and detectable in the urine. The mean cf-RNA integrity index was significantly lower in the urine of ccRCC patients (mean: 0.07, 95%CI: 0.05-0.10) when compared with the urine from control subjects (mean: 0.25, 95%CI: 0.16-0.33) (p < 0.001). The value of the area under the receiver-operating characteristic curve by using the cf-RNA integrity index for the diagnosis of ccRCC was 0.858 with a sensitivity of 68.0% and a specificity of 92.6%. Moreover, the small-sized VEGF mRNA fragment (98 bp) was detected in 31 of 50 urine samples of patients with ccRCC and in only 2 of 50 urine samples of control subjects (p < 0.001) while the detection of the big-sized (420 bp) VEGF mRNA fragment was an infrequent event. Our findings suggest that the small-sized cf-RNA in urine was more abundant in cancer patients. The tumor-related gene VEGF mRNA fragment was detectable in the urine of cancer patients. Our finding may provide a new molecular assay for the diagnosis of renal cell carcinoma.

Liver disease is a major cause of morbidity and mortality worldwide. As in other fields of medicine, there is a stringent need for non-invasive markers to improve patient diagnostics, monitoring and prognostic ability in liver pathology. Cell-free circulating RNA molecules have been recently acknowledged as an important source of potential medical biomarkers. However, many aspects related to the biology of these molecules remain to be elucidated. In this review, we summarize current concepts related to the origin, transportation and possible functions of cell-free RNA. We outline current development of extracellular RNA-based biomarkers in the main forms of non-inherited liver disease: chronic viral hepatitis, hepatocellular carcinoma, non-alcoholic fatty liver, hepato-toxicity, and liver transplantation. Despite recent technological advances, the lack of standardization in the assessment of these markers makes their adoption into clinical practice difficult. We thus finally review the main factors influencing quantification of circulating RNA. These factors should be considered in the reporting and interpretation of current findings, as well as in the proper planning of future studies, to improve reliability and reproducibility of results.

Amniotic fluid (AF) is a complex, dynamic solution that surrounds the fetus and contains cell-free fetal (cff) RNA. Study aims The overall objective of this thesis was to investigate AF cff RNA as a source of fetal gene expression information in normal and abnormal pregnancies. The specific aims were: • To develop an understanding of the mid-trimester AF transcriptome, including the putative tissues sources and biological functions of AF cell-free RNA • To investigate the changes that occur in AF cff RNA with increasing gestational age • To explore AF cff RNA from aneuploid fetuses for gene expression information about abnormal neurodevelopment • To better understand the pathophysiology involved in twin-twin transfusion syndrome by performing global gene expression analysis of AF cff RNA from pregnancies with active disease Methods RNA was isolated from AF supernatants (AFS), amplified and hybridized to whole genome microarrays. Statistically significantly differentially-regulated and/ or “present” genes were identified. Functional analyses were performed with bioinformatics software tools including Ingenuity Pathway Analysis™ (IPA) and the Database for Annotation, Visualization and Integrated Discovery (DAVID). Results • Cell-free RNA in AF is derived from a variety of tissues and provides data on multiple fetal organ systems, including the nervous system. • The tissue expression patterns and enriched biological pathways in AF cff RNA vary with gestational age and, at term, reflect fetal maturation processes. • Mid-trimester AFS from aneuploid fetuses is enriched for nervous system gene expression and neurological disease pathways. • Functional genomic analysis of AFS from TTTS recipient fetuses reveals dysregulation of cardiovascular and nervous system gene expression that precedes intervention with laser therapy. Conclusions AF cff RNA is a s! ource of meaningful biological information about the fetus. Functional genomic analysis of AF cff RNA can reveal novel molecular data about the impact of chromosomal or structural abnormalities on human development. These findings advance the concept of AFS as a gene expression “summary fluid” of the live human fetus.

e16613Background: In prostate cancer (PC), the androgen-receptor isoform that is encoded by the splice variant 7 (AR-V7) is characterized by an absence of the ligand-binding domain that is the targ...

The use of cell-free nucleic acids in the circulation of pregnant women for noninvasive prenatal diagnosis is arguably one of the hottest current topics in prenatal medicine. Between 1997 and the present era this field has gone from basic research to clinical application for diagnosis of fetal gender and Rhesus D status. Over the next few years it is likely that noninvasive prenatal diagnosis for Down syndrome will also be possible. Here we summarize current and future clinical applications of analyzing cell-free fetal DNA and RNA in both maternal and neonatal body fluids, including maternal plasma, serum, whole blood, amniotic fluid, and neonatal saliva. We describe methods to evaluate normal and abnormal fetal and neonatal development using gene expression microarrays. We also discuss the ways in which differentially-regulated gene lists can advance knowledge of both fetal and neonatal biology, as well as suggest novel possibilities for fetal and neonatal treatment.

Background Since there is no validated assay to monitor disease in children with neuroblastoma (NB), we tested whether NB specific cell-free RNA could be detected in their plasma samples. Moreover, with the aim of reducing patients' discomfort, we compared this assay to a recently standardized procedure that uses a larger amount of whole blood. Procedures Using conditions that excluded RNA recovery from contaminating tumor cells, the total amount of cell-free RNA present in healthy children and patients with NB was quantified. Expression of tyrosine hydroxylase (TH) was assayed by quantitative RT-PCR. Results In patients with NB the amount of cell-free RNA was higher than in healthy children. However, it was less and more degraded than in healthy adults. The median amount of cell-free RNA that was reverse transcribed, measured through the use of standard curves for reference genes, was 0.03 (range 0–30) pg of input RNA, that is, always less than 1/10,000 of that reverse transcribed from total RNA extracted from whole cells. Despite the presence of disease and the positive results obtained with RNA extracted from peripheral blood cells, few cell-free RNA samples tested positive by the TH assay. Similar results were obtained also with TH primers specifically designed to amplify 50 bp RNA fragments. Conclusion These findings suggest that for monitoring disease status detection of cell-free tumor-specific RNAs in patients with NB is not a reliable alternative to whole cell RNA. Pediatr Blood Cancer 2010;54:897–903 © 2010 Wiley-Liss, Inc.

Background Cell-free RNA (cfRNA) naturally occurs in blood and has clinical significance. Accurate quantification of these extracellular RNAs in whole blood is hindered by the simultaneous unintended release of cellular RNA and degradation of cfRNA after blood draw. An appropriate blood collection device is needed to stabilize cfRNA during blood processing, transportation and storage, which will ensure cfRNA test reliability. In this study we compared a novel blood collection device against traditional K3EDTA tubes for its ability to stabilize cfRNA in blood when subjected to conditions that can occur during sample storage and shipping. Findings Shipping blood samples drawn into K3EDTA tubes showed a significant increase in mRNA copy numbers for β-actin, c-fos, and 18S rRNA in plasma. In contrast, shipping blood drawn into Cell-Free RNA BCT™s (BCTs) showed only a slight change in mRNA copy numbers for circulating β-actin, c-fos, and 18S rRNA. Moreover, blood stored in K3EDTA tubes at 6°C, 22°C and 30°C for 3 days showed a significant increase in mRNA copy numbers for c-fos and β-actin, whereas samples stored in BCTs only showed a slight increase. Conclusion Our results show that BCTs minimize increases in background RNA levels caused by temperature fluctuations or agitation that can occur during blood sample storage and shipping. This novel blood collection tube could provide a method for obtaining high quality stabilized cfRNA samples for rare RNA target detection and determining accurate cfRNA concentrations.