Serum exosomal lncRNA XIST is a potential non-invasive biomarker to diagnose recurrence of triple-negative breast cancer.

Exosomal lncRNAs secreted by cancer cells can serve as potential biomarkers in the diagnosis and prognosis of various tumours. Here, we are committed to explore the diagnostic and prognostic value of serum exosomal XIST secreted by tumour cells to predict recurrence in patients with triple-negative breast cancer (TNBC). Significant increments in XIST and exo-XIST from tumour tissues and blood serum were found in reoccurring TNBC patients by comparison with non-recurrences. Levels of serum exo-XIST were only significantly increased in TNBC recurrence and no association with other clinicopathological parameters. Additionally, serum exo-XIST levels could be served as an assessment of change in the load of triple-negative breast cancer. Expressions of exo-XIST were markedly decreased after resection of the primary breast tumours and obviously elevated at the time of recurrence. Finally, an obvious association was identified between serum exo-XIST levels and a poorer overall survival (OS) in TNBC patients. Levels of serum exo-XIST may serve as a diagnostic and prognostic biomarker to predict the recurrent TNBC-loading status.

tRFs as Potential Exosome tRNA-Derived Fragment Biomarkers for Gastric Carcinoma.

BACKGROUND: Gastric Carcinoma (GC) is one of the common diseases induced by the interaction of genes and environment. Exosomes are potential markers for several health problems, which contain lipids, proteins, long non-coding RNAs, microRNAs (miRNAs), and tRNA-derived fragments (tRFs). The roles of mRNAs and miRNAs in GC have been studied comprehensively; however, little research was focused on the function of plasma exosomal tRFs. METHODS: We collected plasma samples from fifty healthy controls and fifty GC patients, and all exosomes were isolated with a combined centrifugation and characterized by electron microscopy, western blot, and flow cytometry. The small RNA sequence was performed to detect the plasma exosomal tRFs, and tRFs markers were validated by real-time quantitative PCR. Three exosomal diagnostic tRFs were confirmed by receiver operating characteristic analyses. RESULTS: In this study, we found higher plasma exosomal tRF-25, tRF-38, tRF-18 expression in GC than in controls. Plasma exosomal tRF-25, tRF-38, and tRF-18 showed better accuracy for GC diagnosis. CONCLUSIONS: Our results suggest that plasma exosomal tRF-25, tRF-38, and tRF-18 were biomarkers for GC detection; tRF-25, tRF-38 and tRF-18 might be predictive of GC prognosis.

Identification of lung adenocarcinoma-specific exosome RNAs in peripheral blood by RNA-Seq analysis.

OBJECTIVE: Several plasma-derived exosome RNAs have been identified as key regulators in cancer development. They have been considered as potential biomarkers for a non-invasive "liquid biopsy" to diagnose and assess the progression of cancer. This study aimed to identify human lung adenocarcinoma-specific exosome RNAs in peripheral blood, while assessing the feasibility and efficiency of this recently developed deep-sequencing technology for transcriptome profiling. PATIENTS AND METHODS: Plasma-derived exosome RNAs were isolated from 13 lung adenocarcinoma patients, 3 patients with benign lung diseases, and 15 healthy volunteers. RNA-seq analysis of ribosomal RNA-depleted total RNA was performed. RNAs differentially expressed between lung adenocarcinoma and benign lung diseases or healthy volunteers were identified, followed by GO and KEGG pathway enrichment analyses for the identification of key exosome RNAs associated with lung adenocarcinomas. RESULTS: Significant differentially expressed RNAs, such as UDP glucuronosyltransferase family 1 member A1 (UGT1A1) and BAI1-associated protein 2 like 1 (BAIAP2L1), were identified as differentially expressed between lung adenocarcinoma patients and patients with benign lung diseases. Eight pseudogenes, including Tropomyosin 1 (Alpha) Pseudogene (LOC100129096), Prothymosin, Alpha Pseudogene 2 (PTMAP2), Cell Division Cycle 14C, Pseudogene (CDC14C), Tropomyosin 1 (Alpha) Pseudogene (LOC643634), Ferritin Heavy Chain 1 Pseudogene 2 (FTH1P2), Actin Related Protein 2/3 Complex Subunit 3 Pseudogene 3 (ARPC3P3), Ferritin Heavy Chain 1 Pseudogene 11 (FTH1P11), and Prothymosin Alpha Pseudogene 5 (PTMAP5) were identified from plasma-derived exosomes in lung adenocarcinoma patients, who were more abundant/detectable than healthy volunteers. CONCLUSIONS: Our data indicate that plasma-derived exosome RNAs, UGT1A1, and BAIAP2L1, as well as the eight isolated pseudogenes could serve as diagnostic and prognostic biomarkers for an effective non-invasive "liquid biopsy" of lung adenocarcinomas.

Exosomal miRNA profiling before and after surgery revealed potential diagnostic and prognostic markers for lung adenocarcinoma.

Exosome is a crucial manner for cancer cell to cell communication and circulating exosomes sever as promising diagnostic and prognostic markers for various types of diseases. A predominant type of cargo of exosome is small RNAs, especially miRNAs. Here, we profiled plasma exosomal miRNAs of six lung adenocarcinoma patients before and after surgery, as well as six healthy individuals as normal control. Our profiling revealed 38 upregulated and 37 downregulated exosomal miRNAs in the plasma of lung adenocarcinoma patients. Additionally, we found that most upregulated miRNAs were increased in the lung adenocarcinoma samples of TCGA database. We further evaluated the correlation between the upregulated exosomal miRNAs and overall survival with Kaplan-Meier survival analysis using online databases. Our results suggested that exosomal miR-151a-5p, miR-10b-5p, miR-192-5p, miR-106b-3p, and miR-484 are potential prognostic markers for lung adenocarcinoma. Importantly, we validated candidate miRNAs in lung adenocarcinoma patients before and after surgery as well as in healthy controls and found that miR-484 was significantly increased in the plasma of lung adenocarcinoma patients and strikingly decreased post-surgery. Hence, we provided novel information on lung adenocarcinoma-derived exosomal miRNA and potential non-invasive diagnostic and prognostic markers for lung adenocarcinoma.

Identification of an Exosomal Long Noncoding RNA SOX2-OT in Plasma as a Promising Biomarker for Lung Squamous Cell Carcinoma.

AIMS: Evaluation of nucleic acids in plasma exosomes is a noninvasive method that can be used to detect different types of cancer. The aim of this study was to determine the value of exosomal long noncoding RNAs (lncRNAs) in detecting lung squamous cell carcinoma (LSCC). MATERIALS AND METHODS: A total of 75 LSCC patients and 79 negative control subjects were enrolled in the study. Twenty differentially expressed lncRNAs were evaluated as potential candidates. Exosomes were isolated by ultracentrifugation, and lncRNA levels in exosomes were determined using real-time polymerase chain reaction. Receiver Operating Characteristic (ROC) curves were used to determine specificity and sensitivity. RESULTS: Exosomal SOX2-OT was significantly upregulated in LSCC patients and showed the strongest power in detecting LSCC. The area under the ROC curve was 0.815, and the sensitivity and specificity were 76% and 73.17%, respectively. Moreover, exosomal SOX2-OT levels were significantly correlated with tumor size, TNM stage, and lymph node metastasis. Exosomal SOX2-OT levels were significantly decreased in the postoperative plasma of LSCC patients. CONCLUSION: SOX2-OT may serve as a promising noninvasive plasma-based tumor biomarker for LSCC.

Identification of Altered Circular RNA Expression in Serum Exosomes from Patients with Papillary Thyroid Carcinoma by High-Throughput Sequencing.

BACKGROUND This study aimed to identify altered exosome circular RNA (circRNA) in the serum of patients with papillary thyroid carcinoma using high-throughput sequencing. MATERIAL AND METHODS Serum was collected from three patients with papillary thyroid carcinoma and three patients with a benign thyroid goiter. Exosomes were isolated using an exosome isolation kit and confirmed by transmission electron microscopy. Exosome circRNAs were analyzed by high-throughput sequencing using the HiSeq 4000 sequencer. The differentially expressed circRNAs were confirmed by fluorescence quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS Twenty-two differentially expressed circRNAs were screened, which included three that were upregulated and 19 that were down-regulated in serum from patients with papillary thyroid carcinoma compared with controls. Gene Ontology (GO) enrichment analysis showed that these differentially expressed circRNAs were associated with 16 signaling pathways, including the thyroid hormone signaling pathway, the PI3K-Akt signaling pathway, and the AMPK signaling pathway. Three differentially regulated circRNAs included hsacirc_007293, hsacirc_031752, and hsacirc_020135 were confirmed by qRT- PCR. The expression trends were consistent between the high-throughput sequencing technique and qRT-PCR. CONCLUSIONS The findings from this study have shown that gene regulation can be studied from exosomes obtained from serum samples in patients with papillary thyroid carcinoma, and supports the need for further studies on the role of exosome circRNAs in thyroid cancer.

A serum exosomal microRNA panel as a potential biomarker test for gastric cancer.

The findings from several studies have suggested that circulating miRNAs are imbalanced with the genesis of gastric cancer (GC). Both normal and cancer cells can generate and secrete exosomes, which are nanosized membrane vesicles that can transport microRNAs and proteins. Emerging evidence indicates that the exosomes secreted by cancer cells can be released into the circulatory system. In this study, we investigated whether circulating exosomal miRNAs can be used to discriminate individuals with GC from healthy controls (NCs). Based on the quantitative reverse transcription polymerase chain reaction (qRT-PCR), four miRNAs (miR-19b-3p, miR-17-5p, miR-30a-5p, and miR-106a-5p) related to GC pathogenesis were identified in serum-circulating exosomes from a cohort of 20 healthy controls and 20 individuals with GC in the initial screening phase. The distinguished miRNAs were further validated in the training (90 GC vs. 90 NCs) and blinded phases 20 GC vs. 20 NCs), and the area under receiver operating characteristic (ROC) curves of these miRNAs were analyzed. We found that miR-19b and miR-106a were markedly overexpressed in individuals with GC compared to NCs (P < 0.0001). Besides, the ROC analyses yielded the AUC values of 0.786 for miR-106a-5p, 0.769 for miR-19b-3p and combined ROC analysis revealed the highest AUC value of 0.814 in discriminating GC patients from NCs. Furthermore, based on the model developed from the data, a signature composed of the 2 miRNAs (miR-19b-3p and miR-106a-5p) correctly discriminated 19 out of 20 GC serum samples (95% sensitivity) and 18 out of 20 normal samples (90% specificity) in the blinded phase. Moreover, the validated miRNAs were related to GC lymphatic metastasis (P < 0.01) and expressed at higher levels in stages III and IV compared to I and II stages (P < 0.05). These results suggest that serum exosomal miR-19b-3p and miR-106a-5p are novel potential biomarkers for detecting GC.

Clinical correlates of monospecific anti-PM75 and anti-PM100 antibodies in a tri-nation cohort of 1574 systemic sclerosis subjects.

OBJECTIVE: Autoantibodies directed against the two principal antigens of the human exosome complex, PM75 and PM100, are present in systemic sclerosis (SSc) sera and have been associated with myositis and calcinosis. However, there is a paucity of data on the clinical correlates of these autoantibodies separately and in the absence of other SSc-specific antibodies. The aim of this study was to assess the clinical correlates of monospecific anti-PM75 and anti-PM100 in SSc. METHODS: A tri-nation cohort of 1574 SSc subjects was formed, clinical variables were harmonized and sera were tested for anti-PM75 and anti-PM100 antibodies using a line immunoassay. RESULTS: Forty-eight (3.0%) subjects had antibodies against PM75 and 18 (1.1%) against PM100. However, only 16 (1%) had monospecific anti-PM75 antibodies and 11 (0.7%) monospecific anti-PM100 antibodies (i.e. in isolation of each other and other SSc-specific antibodies). Monospecific profiles of each autoantibody included more calcinosis. An increased frequency of myositis was only seen in subjects positive for both anti-PM75 and anti-PM100 antibodies. Lung disease was only associated with anti-PM75 and subjects with anti-PM100 antibodies had better survival compared to other antibody subsets. CONCLUSION: The prevalence of monospecific anti-PM75 and anti-PM100 antibodies in this large SSc cohort was low. Disease features associated with anti-PM/Scl antibodies may depend on particular and possibly multiple antigen specificities. However, due to the small samples, these results need to be interpreted with caution. International collaborations are key to understanding the clinical correlates of uncommon serological profiles in SSc.