lncRNAs In Plasma Research Articles

Plasma-derived exosomal long noncoding RNAs of pancreatic cancer patients as novel blood-based biomarkers of disease

BackgroundPancreatic cancer (PaCa) is one of the most intractable and fatal malignancies and is associated with the dysregulation of long noncoding RNAs (lncRNAs), which are a large class of noncoding RNAs larger than 200 nt that act as competing endogenous RNAs or sponges for miRNAs to induce tumour biological behaviours. However, their clinical value in treating pancreatic cancer has been poorly explained, but they are essential for improving the prognosis of PaCa patients.MethodsWe analysed the plasma-derived exosomal lncRNA profiles of PaCa patients by using whole-transcriptome sequencing analysis and identified significantly differentially expressed lncRNAs, including LINC01268, LINC02802, AC124854.1, and AL132657.1. In the current study, the expression levels of four plasma-derived exosomal lncRNAs in PaCa plasma were validated via quantitative real-time polymerase chain reaction (qRT‒PCR). The relationship between the expression of the four lncRNAs and the clinicopathological features of patients with PaCa was also evaluated.ResultsWe demonstrated that exosomal LINC01268, LINC02802, AC124854.1 and AL132657.1 were highly expressed in PaCa plasma compared with those in normal controls; moreover, they were positively correlated with the serum expression of carbohydrate antigen 19–9 (CA19-9). The receiver operating characteristic curves (AUCs) of the four lncRNAs were 0.8421, 0.6544, 0.7190, and 0.6321, and the AUC value of the combination of the four exosomal lncRNAs increased to 0.8476, with a sensitivity of 0.72 and specificity of 0.89. These results suggested that the plasma-derived exosomal genes LINC01268, LINC02802, AC124854.1, and AL132657.1 may be novel diagnostic markers for PaCa.ConclusionsOur research demonstrated that the plasma-derived exosomal lncRNAs of PaCa patients are novel blood-based biomarkers of disease.

The lncRNAs Gas5, MALAT1 and SNHG8 as diagnostic biomarkers for epithelial malignant pleural mesothelioma in Egyptian patients

Long noncoding RNAs have been shown to be involved in a myriad of physiological and pathological pathways. To date, malignant pleural mesothelioma (MPM) is considered an extremely aggressive cancer. One reason for this is the late diagnosis of the disease, which can occur within 30–40 years of asbestos exposure. There is an immense need for the development of new, sensitive, inexpensive and easy methods for the early detection of this disease other than invasive methods such as biopsy. The aim of this study was to determine the expression of circulating lncRNAs in mesothelioma patient plasma to identify potential biomarkers. Ten previously identified lncRNAs that were shown to be aberrantly expressed in mesothelioma tissues were selected as candidates for subsequent validation. The expression of the ten selected candidate lncRNAs was verified via quantitative PCR (qPCR) in human plasma samples from mesothelioma patients versus healthy controls. The expression levels of circulating GAS5, SNHG8 and MALAT1 were significantly greater in plasma samples from patients than in those from controls. The ROC analysis of both MALAT1 and SNHG8 revealed 88.89% sensitivity and 66.67% specificity. The sensitivity of these markers was greater than that of GAS5 (sensitivity 72.22% and specificity 66.67%). The regression model for GAS5 was statistically significant, while that for SNHG8 and MALAT1 was not significant due to the small sample size. The area under the curve (AUC) of the three ROC curves was acceptable and significant: 0.7519 for GAS5, 0.7352 for SNHG8 and 0.7185 for MALAT1. This finding confirmed their ability to be used as markers. The three lncRNAs were not affected by age, sex or smoking status. The three lncRNAs showed great potential as independent predictive diagnostic biomarkers. Although the prediction model for MALAT1 did not significantly differ, MALAT1 was significantly expressed in patients more than in controls (p = 0.0266), and the recorded sensitivity and specificity were greater than those of GAS5.

Abstract P1061: Salivary Extracellular Vesicle-associated LncRNAs As Novel Non-invasive Biomarkers For Acute Decompensated Heart Failure: The Pioneering SEAL-HF Study

Acute Decompensated Heart Failure (ADHF) is a major global health concern, and early diagnosis is critical for effective management. Non-invasive biomarkers have the potential to improve patient outcomes substantially. In this study, we investigated the presence of extracellular vesicle (EV)-associated long non-coding RNAs (lncRNAs) in plasma of ADHF patients and explored their non-invasive detection in saliva as the foundation of the SEAL-HF study. We performed RNA-sequencing on plasma-derived EVs from ADHF patients at admission and discharge and healthy controls to identify differentially expressed lncRNAs and mRNAs, using a fold change cutoff of ±1.5 and an adjusted p-value of <0.05. Subsequent validation was carried out via qRT-PCR on plasma EV RNA samples from 182 patients. Salivary EVs were isolated and enriched, and their EV RNA content was profiled. Transcriptomic analysis unveiled several dysregulated EV-derived mRNAs and lncRNAs in ADHF patients compared to controls. Importantly, four lncRNAs (LINC00989, lnc-CALML5, AC092656.1, and RMRP) exhibited significant changes between the acute congestive phase and decongestion after diuresis and were found to circulate mainly within the EV compartment. Salivary EVs contained EV protein markers ALIX, CD81, and heart-derived protein marker Troponin T. qRT-PCR assay demonstrated the presence of LINC00989, lnc-CALML5, AC092656.1, and RMRP in salivary EVs, as well as cardiac-specific genes such as PLN. Our results highlight the potential of salivary EV-associated lncRNAs as non-invasive biomarkers for ADHF diagnosis, laying the groundwork for the SEAL-HF study and future clinical applications.

Polycyclic aromatic hydrocarbons exposure and plasma lncRNA signature: A profile and functional analysis

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants that pose detrimental effects on human health, and the exploration of the associations of PAHs exposure with long non-coding RNA (lncRNA) may provide novel clues to the underlying mechanisms. In the present study, we detected 10 urinary PAHs metabolites by GC–MS and plasma lncRNAs levels by Human LncRNA Array v4 among 230 participants from two panels (160 in the Shiyan panel and 70 in the Wuhan-Zhuhai panel). We applied linear regression models to assess the associations between PAHs metabolites and lncRNAs separately in each panel and combined the results using fixed-effect meta-analysis. To explore the potential origin of PAHs-related lncRNAs in plasma, we estimated their tissue-specificity and associations between lncRNAs levels in plasma and leukocytes. Leukocytes mRNA sequencing data and RNA binding proteins were utilized to explore implicated pathways of identified lncRNAs. We found that urinary 1-hydroxyphenanthrene (1-OH-Phe) was inversely associated with 8 lncRNAs and positively associated with 1 lncRNA, as well as 9-hydroxyphenanthrene (9-OH-Phe) was inversely associated with 11 lncRNAs (FDR < 0.1). Tissue specificity analysis using Genome Tissue Expression database suggested that several identified lncRNAs might specifically express in organs targeted by PAHs exposure (lung, liver, heart, kidney, and brain). Besides, plasma levels of 1-OH-Phe related ENSG00000260616 and 9-OH-Phe related STARD4-AS1 were inversely associated with their intra-leukocytes levels (P value < 0.05). Notably, STARD4-AS1 was positively associated with the expression levels of its neighboring protein-coding gene (CAMK4 and STARD4) in leukocytes and were involved in pathways related to cellular response to DNA damage, which we further confirmed using DNA damage biomarker, 8-hydroxydeoxyguanosine. Functional analysis also revealed vital pathways related to cytokine-mediated signaling and glucose homeostasis. Our findings provided novel insights into plausible biological mechanisms underlying the adverse effects of PAHs exposure.

Plasma long noncoding RNAs lncDC and THRIL as potential diagnostic markers of adult primary immune thrombocytopenia.

Immune thrombocytopenia (ITP) is a common acquired hemorrhagic disease without "gold standard" for the diagnosis, long non-coding RNA (lncRNAs) can participate in regulating gene expression through various mechanisms and may play a role in immune intolerance in ITP. Several previous studies have confirmed that lncRNA lncDC and THRIL are involved in the development of autoimmune diseases. This study investigates the relationship between expression levels of two plasma lncRNAs (lncDC and THRIL) and clinical characteristics of adult primary ITP patients, ascertain their potential applications as diagnostic markers of ITP. We recruited 102 subjects, including 41 ITP patients, 41 healthy controls (HCs) and 20 patients under myelosuppression phase after chemotherapy (MS). qRT-PCR was used to detect the expression of two lncRNAs in the peripheral blood plasma of the three groups. Receiver operating characteristic (ROC) curves were used to test the diagnostic efficacy of lncDC and THRIL in ITP. The expression level of lncDC was downregulated in ITP patients compared with HCs (p=. 012) and MS (p=.035), whereas THRIL was significantly upregulated (p=.0005, p < . 0001). We further revealed that lncDC has a high sensitivity (78. 05%), while THRIL has a high specificity (97. 56%). The area under the curve (AUC) (0.869, 95% CI: 0.795-0.943, p < .0001) of the ROC curve for this combination increased significantly. THRIL and lncDC expression levels were changed in adult ITP patients. The lncRNAs lncDC and THRIL can serve as potential diagnostic markers for adult primary ITP.

PRELIMINARY RESULTS OF lncRNAs AS BIOMARKERS FOR COLORECTAL CANCER DIAGNOSIS

Abstract Introduction lncRNAs are strands larger than 200 nucleotides that do not encode proteins. They have regulatory functions in cell proliferation, apoptosis and migration. They are stable over a long period and may have diagnostic value in colorectal cancer (CRC). Their availability as effective biomarkers for CRC screening would represent a substantial advance, as tests could be performed with minimal risk and wide acceptance. The aim of this study is to evaluate selected lncRNAs in plasma as potential diagnostic biomarkers in CRC. Methods Prospective cohort study between patients operated on for CRC (cases) and healthy patients (controls). Blood samples were processed in the biobank to obtain plasma by centrifugation. Subsequently, the levels of three CRC-related lncRNAs (HOTAIR, CCAT2 and PVT1) were determined in the laboratory of the Electroanalysis Group of the University of Oviedo (GEUO). Results In the initial results, an overexpression of the three genes (HOTAIR, CCAT2 and PVT1) was observed in CRC patients, with HOTAIR being the one that best differentiates between CRC and healthy patients. In addition, the combined determination of the three lncRNAs could obtain better results than the individual determination of each of them. Conclusions The lncRNAs studied are overexpressed in the CRC patient sample. The sample size needs to be increased to confirm this trend. It is logical to postulate that molecular technologies will lead to the development of better screening modalities and individualised treatments.

The lncRNAs/miR-30e/CHI3L1 Axis Is Dysregulated in Systemic Sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease with completely undefined etiology and treatment difficulties. The expression of both protein coding and non-coding RNAs is dysregulated during disease development. We aimed to examine a possible regulatory axis implemented in the control of chitinase-3 like protein 1 (CHI3L1) or YKL-40, an inflammation-associated glycoprotein, shown to be elevated in SSc. A panel of seven miRNAs and three lncRNAs potentially involved in the control of CHI3L1 were selected on the basis of in silico analysis. TagMan assay was used to evaluate the expression levels of miRNAs and RT-qPCR for lncRNAs in white blood cells (WBCs) and plasma from SSc patients and healthy controls. Among the eight screened miRNAs, miR-30e-5p (p = 0.04) and miR-30a-5p (p = 0.01) were significantly downregulated in WBCs and plasma of SSc patients, respectively. On the contrary, the expression of the metastasis associated lung adenocarcinoma transcript 1 (MALAT1) (p = 0.044) and the Nuclear enriched abundant transcript 1 (NEAT1) (p = 0.008) in WBCs was upregulated compared to the controls. Increased levels of MALAT1 and NEAT1 could be associated with the downregulation of miR-30e-5p and miR-30a-5p expression in WBCs and plasma. We present novel data on the involvement of a possible regulatory axis lncRNAs/miR-30e/CHI3L1 in SSc and hypothesize that MALAT1 and NEAT1 could act as miR-30e-5p and miR-30a-5p decoys. This may be a reason for the increased serum levels of CHI3L1 in SSc patients.

Circulating lncRNA UCA1 and lncRNA PGM5-AS1 act as potential diagnostic biomarkers for early-stage colorectal cancer.

Background: Colorectal cancer (CRC) is one of the most common and significant malignant diseases worldwide. In the present study, we evaluated two long non-coding RNAs (lncRNAs) in CRC patients as diagnostic markers for early-stage CRC.Methods: Using Gene Expression Omnibus (GEO) datasets GSE102340, GSE126092, GSE109454 and GSE115856, 14 differentially expressed lncRNAs were identified between cancer and adjacent tissues, among which, the two most differentially expressed were confirmed using quantitative real-time polymerase chain reaction (qRT-PCR) in 200 healthy controls and 188 CRC patients. A receiver operating characteristic (ROC) analysis was employed to evaluate the diagnostic accuracy for CRC.Results: From four GEO datasets, three up-regulated and eleven down-regulated lncRNAs were identified in CRC tissues, among which, lncRNA urothelial carcinoma-associated 1 (UCA1) and lncRNA phosphoglucomutase 5-antisense RNA 1 (PGM5-AS1) were the most significantly up- and down-regulated lncRNAs in CRC patient plasma, respectively. The area under the ROC curve was calculated to be 0.766, 0.754 and 0.798 for UCA1, PGM5-AS1 and the combination of these two lncRNAs, respectively. Moreover, the diagnostic potential of these two lncRNAs was even higher for the early stages of CRC. The combination of UCA1 and PGM5-AS1 enhanced the AUC to 0.832, and when the lncRNAs were used with carcinoembryonic antigen (CEA), the AUC was further improved to 0.874.Conclusion: In the present study, we identified two lncRNAs, UCA1 and PGM5-AS1, in CRC patients’ plasma, which have the potential to be used as diagnostic biomarkers of CRC.

Identification of Differentially Expressed Plasma lncRNAs As Potential Biomarkers for Breast Cancer

BackgroundBreast cancer is the most common malignant tumor in women and is not easy to diagnose. Increasing evidence has underscored that long non-coding RNAs (lncRNAs) play important regulatory roles in the occurrence and progression of many cancers, including breast cancer. We aimed to identify lncRNAs in plasma as potential biomarkers for breast cancer. Patients and MethodsWe analyzed the Gene Expression Omnibus (GEO) datasets GSE22820, GSE42568, and GSE65194 to identify the common differential genes between cancer tissues and adjacent tissues. Then 14 lncRNAs were identified among the common differential genes and validated by using real-time quantitative polymerase chain reaction in 92 patients with breast cancer and 100 healthy controls. Receiver operating characteristic (ROC) curves were constructed to evaluate their diagnostic value for breast cancer. ResultsIntegrated analysis of the GEO datasets identified three significantly upregulated and 11 downregulated lncRNAs in breast cancer tissues. Compared with healthy controls, MIAT was significantly upregulated in breast cancer patient plasma, and LINC00968 and LINC01140 were significantly downregulated. ROC curve analysis suggested that these three lncRNAs can discriminate breast cancer from healthy individual with high specificity and sensitivity. ConclusionThis research identified three differentially expressed lncRNAs in breast cancer patient plasma. Our data suggest that these three lncRNAs can be used as potential diagnostic biomarkers of breast cancer.

Identification of differentially expressed lncRNAs as potential plasma biomarkers for active tuberculosis

BackgroundTuberculosis, one of the deadliest infectious diseases worldwide, is difficult to diagnose. As long noncoding RNAs (lncRNAs) were demonstrated to be promising biomarkers, we aimed to identify lncRNAs in plasma as potential biomarkers for tuberculosis. MethodsWe analyzed a GEO dataset (GSE94907) to identify the differential lncRNAs in serum exosomes between active tuberculosis (ATB) patients and healthy controls. To search for promising candidates that can be used for tuberculosis diagnosis, we excluded low-abundance lncRNAs using a cutoff value of FPKM >5. Four lncRNAs were selected for validation using real-time quantitative PCR in 69 ATB patients and 69 healthy individuals. A receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic value of these lncRNAs for ATB. ResultsIntegrated analysis of the GEO dataset and NONCODE database identified nine dysregulated lncRNAs in ATB patient serum exosomes. Compared with the heathy controls, NONHSAT101518.2, NONHSAT067134.2, NONHSAT148822.1 and NONHSAT078957.2 were significantly downregulated in ATB patient plasma. ROC curve analysis suggests that these four lncRNAs can discriminate ATB from healthy individuals with high specificity and sensitivity. ConclusionWe identified four differentially expressed lncRNAs in ATB patient plasma that can be used as potential diagnostic biomarkers of ATB.

A panel of extracellular vesicle long noncoding RNAs in seminal plasma for predicting testicular spermatozoa in nonobstructive azoospermia patients.

Whether the testis-specific extracellular vesicle (EV) long noncoding RNAs (lncRNAs) in seminal plasma could be utilized to predict the presence of testicular spermatozoa in nonobstructive azoospermia (NOA) patients? Our findings indicate that the panel based on seminal plasma EV lncRNAs was a sensitive and specific method in predicting the presence of testicular spermatozoa and may improve clinical decision-making of NOA. The adoption of sperm retrieval techniques, especially microdissection testicular sperm extraction (mTESE), in combination with ICSI has revolutionized treatment for NOA. However, there are no precise and noninvasive methods for predicting whether there are testicular spermatozoa in NOA patients before mTESE. RNA sequencing was performed on seminal plasma EVs from 6 normozoospermic men who underwent IVF due to female factor and 5 idiopathic NOA patients who failed to obtain testicular spermatozoa by mTESE and were diagnosed as having Sertoli cell-only syndrome by postoperative pathology. A biomarker panel of lncRNAs was constructed and verified in 96 NOA patients who underwent mTESE. Decision-making process was established based on the panel in seminal plasma EVs from 45 normozoospermia samples, 43 oligozoospermia samples, 62 cryptozoospermia samples, 96 NOA samples. RNA sequencing was done to examine altered profiles of EV lncRNAs in seminal plasma. Furthermore, a panel consisting of EV lncRNAs was established and evaluated in training set and validation sets. A panel consisting of nine differentially expressed testis-specific lncRNAs, including LOC100505685, SPATA42, CCDC37-DT, GABRG3-AS1, LOC440934, LOC101929088 (XR_927561.2), LOC101929088 (XR_001745218.1), LINC00343 and LINC00301, was established in the training set and the AUC was 0.986. Furthermore, the AUC in the validation set was 0.960. Importantly, the panel had a unique advantage when compared with models based on serum hormones from the same group of NOA cases (AUC, 0.970 vs 0.723; 0.959 vs 0.687, respectively). According to the panel of lncRNAs, a decision-making process was established, that is when the score of an NOA case exceeds 0.532, sperm retrieval surgery may be recommended. In the future, the sample size needs to be further expanded. Meanwhile, the regulatory functions and mechanism of lncRNAs in spermatogenesis also need to be elucidated. When the score of our panel is below 0.532, subjecting the NOA patients to ineffective surgical interventions may not be recommended due to poor sperm retrieval rate. This work was supported by the National Natural Science Foundation of China (81871110, 81971314 and 81971759); the Guangdong Special Support Plan-Science and Technology Innovation Youth Top Talents Project (2016TQ03R444); the Science and Technology Planning Project of Guangdong Province (2016B030230001 and 201707010394); the Key Scientific and Technological Program of Guangzhou City (201604020189); the Pearl River S&T Nova Program of Guangzhou (201806010089); the Transformation of Scientific and Technological Achievements Project of Sun Yat-sen University (80000-18843235) and the Youth Teacher Training Project of Sun Yat-sen University (17ykpy68 and 18ykpy09). There are no competing interests related to this study. N/A.

Identification of differentially expressed circulating exosomal lncRNAs in IgA nephropathy patients

BackgroundAlthough immunoglobulin A nephropathy (IgAN) is one of the foremost primary glomerular disease, treatment of IgAN is still in infancy. Non-invasive biomarkers are urgently needed for IgAN diagnosis. We investigate the difference in expression profiles of exosomal long non-coding-RNAs (lncRNAs) in plasma from IgAN patients compared with their healthy first-degree relatives, which may reveal novel non-invasive IgAN biomarkers.MethodsWe isolated exosomes from the plasma of both IgAN patients and their healthy first-degree relatives. High-throughput RNA sequencing and real-time quantitative polymerase chain reaction (qRT-PCR) was used to validate lncRNA expression profiles. Pathway enrichment analysis was used to predict their nearest protein-coding genes.ResultslncRNA-G21551 was significantly down-regulated in IgAN patients. Interestingly, the nearest protein-coding gene of lncRNA-G21551 was found to be encoding the low affinity receptor of the Fc segment of immunoglobulin G (FCGR3B).ConclusionsExosomal lncRNA-G21551, with FCGR3B as the nearest protein-coding gene, was down-regulated in IgAN patients, indicating its potential to serve as a non-invasive biomarker for IgAN.

Screening of long non-coding RNAs markers in plasma of children with chronic gastritis

ObjectiveThe study aimed to detect and analyze long non-coding RNAs (lncRNAs) in plasma of children diagnosed with chronic gastritis, and to explore its biological functions and involved signaling pathways. MethodsThe plasma samples were collected from six children that were diagnosed with chronic gastritis by physical examination, gastroscopy, and pathological examination and six healthy children. The plasma samples were assayed for determining the expression profiles of lncRNA based upon the gen chip detection. The specific expression of lcnRNA in plasma of children with chronic gastritis was analyzed and its biological functions were speculated. ResultsFive lncRNAs (RP11-697M17.1, RP11-388M20.9, AFAP1-AS1, BC062758, and XLOC001406) were significantly up-regulated, and five lncRNAs (UNQ697, BX571672.5, CYP4F35P, ANKRD20A5P, and AL832737) were observed to be significantly down-regulated. The lncRNAs RP11-697M17.1, and UNQ697 were detected with the highest up-regulation and down-regulation, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that the up-regulated lncRNAs were significantly enriched in 20 signaling pathways such as phosphoinositide-3-kinase–protein kinase B (PI3K-Akt) pathway, and the down-regulated lncRNAs target genes were significantly enriched in 20 signaling pathways such as the metabolic pathway. ConclusionThe analysis of the lncRNA expression profiles in plasma of children with chronic gastritis revealed that the lncRNA RP11-697M17.1, and lncRNA UNQ697 may act as plasma markers for predicting chronic gastritis in children.

Circulating lncRNA H19 may be a useful marker of response to neoadjuvant chemotherapy in breast cancer.

Novel biomarkers are needed to predict the effectiveness of the treatment of presurgical neoadjuvant chemotherapy (NAC) in breast cancer (BC). This is an exploratory study to assess the impact of 3 cancer-related long non-coding RNAs (lncRNAs) (H19, MALAT1 and GA5) in blood plasma of patients with BC in predicting the response to NAC. The plasma levels of RNAs were relatively measured by quantitative PCR at baseline, and at the end of the fourth cycle of NAC in patients with locally advanced BC. Only H19 was associated with patients' characteristics, and with the response to NAC. Higher plasma expression of H19 was associated with younger age at diagnosis, triple negative tumors, and Ki-67 index. Patients with a pathological complete response (20%) had lower pre-therapeutic levels of H19 compared with the non-complete responders (relative levels 0.1 vs 0.2, respectively, P: 0.04). In addition, the patients with higher degree of downstaging of initial tumors had lower baseline levels of H19 among non-complete responders. Our study reveals that H19, but not MALAT1 and GAS5, may be a useful marker of response to NAC in BC.

Distinct Circulating Expression Profiles of Long Noncoding RNAs in Heart Failure Patients With Ischemic and Nonischemic Dilated Cardiomyopathy.

Ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM), with distinct long-term prognosis and responses to treatment, are two major problems that lead to heart failure (HF) ultimately. In this study, we investigated the long noncoding RNA (lncRNA) and messenger RNA (mRNA) expressions in the plasma of patients with DCM and ICM and analyzed the different lncRNA profile between the two groups. The microarray analysis identified 3,222 and 1,911 significantly differentially expressed lncRNAs and mRNAs between DCM and ICM group. The most enriched upregulated functional terms included positive regulation of I-kappaB kinase/nuclear factor-kappaB signaling and regulation of cellular localization, while the top 10 downregulated genes mainly consisted of acid secretion and myosin heavy chain binding. Furthermore, the Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the differentially expressed lncRNA-coexpressed mRNAs between DCM and ICM group were significantly enriched in the natural killer cell mediated cytotoxicity and ras signaling pathway respectively. Quantitative real-time PCR confirmed 8 of 12 lncRNAs were upregulated in DCM group compared to ICM group which was consistent with the initial microarray results. The lncRNA/mRNA coexpression network indicated the possible functions of the validated lncRNAs. These findings revealed for the first time the specific expression pattern of both protein-coding RNAs and lncRNAs in plasma of HF patients due to DCM and ICM which may provide some important evidence to conveniently identify the etiology of myocardial dysfunctions and help to explore a better strategy for future HF prognosis evaluation.

Differential Plasma Expression Profiles of Long Non-Coding RNAs Reveal Potential Biomarkers for Systemic Lupus Erythematosus.

Identify long non-coding RNAs (lncRNAs) that might serve as biomarkers for systemic lupus erythematosus (SLE) and explore the biological functions of the identified lncRNAs. In the screening phase, we examined the lncRNA expression profile of plasma samples from 24 patients with SLE and 12 healthy controls (HCs) using lncRNA microarray with pooled samples. The candidate lncRNAs were verified in individual samples by quantitative real-time (qRT)-PCR. In the independent validation stage, the identified lncRNAs were evaluated in 240 patients with SLE and 120 HCs. The identified lncRNAs were assessed further in an external validation stage including patients with rheumatoid arthritis (RA) and primary Sjögren’s syndrome (pSS). In addition, we constructed correlated expression networks including coding–non-coding co-expression and competing endogenous RNAs (ceRNAs). Plasma levels of linc0597, lnc0640, and lnc5150 were elevated in SLE patients compared with those of HCs, whereas levels of GAS5 and lnc7074 were decreased. Five lncRNAs were identified as potential SLE biomarkers with an area under the receiver operating characteristic curve (AUC) ranging from 0.604 to 0.833 in the independent validation phase. This panel of five lncRNAs had high diagnostic accuracy for SLE (AUC = 0.966) and distinguished SLE from RA and pSS (AUC = 0.683 and 0.910, respectively). Co-expression analysis showed that GAS5, lnc0640, and lnc5150 may participate in the SLE pathogenesis through the MAPK pathway. The ceRNA network indicated that GAS5, lnc0640, lnc3643, lnc6655, and lnc7074 bind competitively with microRNAs regulating the expression of target genes. Aberrant expression and related pathways suggest the important role of lncRNAs in SLE pathogenesis. In addition, the panel of five lncRNAs (GAS5, lnc7074, linc0597, lnc0640, and lnc5150) in plasma could be used as SLE biomarkers.

The use of Human Inflammatory Response and Autoimmunity RT2 lncRNA PCR Array for plasma examination in breast cancer patients prior to therapy.

Long non-coding RNAs (lncRNAs) are defined as RNA molecules longer than 200 nucleotides with poor protein-coding capacity and key functions in regulation of gene expression. Dysregulations of lncRNAs (e.g. HOTAIR and MALAT I) were detected in plasma of breast cancer (BC) patients. Plasma samples are examined as liquid biopsies for purposes of non-invasive diagnostics therefore the research of plasma lncRNAs as potential plasma biomarkers became highly topical. 84 lncRNAs were profiled in 18 plasma samples - 9 BC patients and 9 age-matched healthy - using Human Inflammatory Response & Autoimmunity RT2 lncRNA PCR Array. Total RNA from plasma samples was isolated using miRNeasy Serum/Plasma Kit. Although a pre-amplification recommended for quantification from small starting RNA amounts was used, only 3 lncRNAs (A2ML1-AS1, GAS5 and SNHG5) were detected in all plasma samples. A total of 72 lncRNAs (e.g. HOTAIR or MALAT I) were detected only in some samples and 9 lncRNAs were not detected in any samples. No significant differences were observed in levels of plasma lncRNAs between the BC patients and healthy controls despite the fact that our panel contained also the lncRNAs whose levels were previously reported as significantly different in plasma or cancer tissues (e.g. GAS5, HOTAIR, MALAT I) in BC patients. Detection of lncRNAs in plasma is due to their low concentrations quite difficult as compared with tissues. Our findings suggest that analysis of plasma lncRNAs using this technology is not suitable for use as non-invasive diagnostic tool in BC patients.

A Plasma Long Noncoding RNA Signature for Early Detection of Lung Cancer

The early detection of lung cancer is a major clinical challenge. Long noncoding RNAs (lncRNAs) have important functions in tumorigenesis. Plasma lncRNAs directly released from primary tumors or the circulating cancer cells might provide cell-free cancer biomarkers. The objective of this study was to investigate whether the lncRNAs could be used as plasma biomarkers for early-stage lung cancer. By using droplet digital polymerase chain reaction, we determined the diagnostic performance of 26 lung cancer–associated lncRNAs in plasma of a development cohort of 63 lung cancer patients and 33 cancer-free individuals, and a validation cohort of 39 lung cancer patients and 28 controls. In the development cohort, 7 of the 26 lncRNAs were reliably measured in plasma. Two (SNHG1 and RMRP) displayed a considerably high plasma level in lung cancer patients vs. cancer-free controls (all P < .001). Combined use of the plasma lncRNAs as a biomarker signature produced 84.13% sensitivity and 87.88% specificity for diagnosis of lung cancer, independent of stage and histological type of lung tumor, and patients' age and sex (all P > .05). The diagnostic value of the plasma lncRNA signature for lung cancer early detection was confirmed in the validation cohort. The plasma lncRNA signature may provide a potential blood-based assay for diagnosing lung cancer at the early stage. Nevertheless, a prospective study is warranted to validate its clinical value.

Circulating Long Noncoding RNA LIPCAR Acts as a Novel Biomarker in Patients with ST-Segment Elevation Myocardial Infarction.

BackgroundLong noncoding RNAs (lncRNAs) recently have been implicated in the pathological processes of cardiovascular diseases. In this study, LncRNADisease database and PubMed database were used to screen myocardial infraction (MI)-related lncRNAs and to investigate the diagnostic role of lncRNAs in ST-segment elevation myocardial infraction (STEMI).Material/MethodsForty-six patients with STEMI and 40 healthy controls were included in the study. Venous blood samples acquired at different time points and the expression levels of lncRNAs in plasma were measured by qRT-PCR. In addition, other blood samples were collected before and after percutaneous coronary intervention (PCI). Correlation analysis and receiver operating characteristic (ROC) curve were used to assess the diagnosis value of the markers. All included patients were followed up for 12±1 months.ResultsNine MI-related lncRNAs were selected from the database. The qRT-PCR results showed that the expression of hypoxia inducible factor 1A antisense RNA 2 (aHIF), member 1 opposite strand/antisense transcript 1 (KCNQ1OT1), and mitochondrial long noncoding RNA uc022bqs.1 (LIPCAR) were significantly increased in patients with STEMI compared to the control patients. The ROC curve showed that LIPCAR (AUC=0.782, 95% CI: 0.707–0.0.894) had better diagnostic accuracy. Moreover, correlation analysis indicated that LIPCAR were positively correlated with myocardial enzymes and negatively correlated with left ventricular ejection fraction. The level of LIPCAR in STEMI patients after PCI was lower (P<0.05). Multivariate regression analysis indicated that higher levels of LIPCAR were independent predictors of major adverse cardiovascular events in patients with STEMI (HR=5.93; 95% CI, 1.46–9.77; P=0.001).ConclusionsHighly expressed LIPCAR in plasma may serve as a warning sign for the diagnosis of STEMI.

Microarray Analysis of Long Noncoding RNAs in the Heart and Plasma of Type 2 Diabetic db/db Mice

ObjectiveDiabetic cardiomyopathy (DCM) refers to diabetes‐associated changes in the structure and function of the myocardium that is not directly attributable to other confounding factors such as coronary heart disease or hypertension. Long noncoding RNAs (lncRNAs) are emerging as the regulator of the development, proliferation, and aging of cardiovascular cells and the pathogenesis of cardiac hypertrophy and heart failure. Little is known regarding lncRNA expression profiles in DCM. The present study was to develop lncRNA expression profiles of the heart and serum of type 2 db/db mice with and without DCM and identify candidate genes for DCM.ResultsEchocardiography results indicate that there was no significant differences in the thickness of left ventricular wall, left ventricular end‐diastolic volume, the peak velocity of mitral E and A waves, isovolumic contraction time of the left ventricle, ejection time of the left ventricle, and myocardial performance index between type2 db/db mice and C57BL/6 controls at 6–8 weeks of age. Left ventricular end‐systolic volume was significantly increased, and ejection fraction and mitral E/A ratio were significantly decreased in db/db mice with DCM at 18–20 weeks of age compared with age‐matched controls. Profiling revealed differentially expressed (DE; adjusted P –value&lt;0.05) lncRNAs in heart and plasma were 663 and 152 whereas the mRNA expressions in the same order were 447 and 127 of Wild type (C57BL/6, db/db) mice vs type 2 db/db (C57BL/6, db/db) whereas in the Wild Type old (C57BL/6, db/db) mice vs type 2 db/db with DCM (C57BL/6, db/db) total LncRNA and mRNA deregulated in heart were 816 and 662 whereas the mRNA expression in the same order were 662 and 2580.ConclusionDCM is associated with changes in global patterns of lncRNA expression. Our study lays the foundation for further studies defining the role of individual lncRNAs in the pathogenesis of DCM.Support or Funding InformationThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.