The Influence of Extracellular RNA on Cell Behavior in Health, Disease and Regeneration

Multifaceted roles of extracellular RNAs in different diseases

Extracellular RNAs (exRNAs) are novel circulating factors that can be used as biomarkers in various diseases. Their unique and diverse kinds, as well as their role as biomarkers, make them significant biomarkers. There has been immense work carried out since the discovery of exRNAs in circulation and other biological fluids to catalog and determine whether exRNAs may be utilized as indicators for health and illness. In this review, we aim to understand the current state of exRNAs in relation to various diseases and their potential as biomarkers. We will also review current issues and challenges faced in using exRNAs, with clinical and lab trials, that can be used as viable markers for different diseases.

Microbial extracellular RNAs and their roles in human diseases

IMPACT STATEMENT

The number of commensal bacteria in the body surpasses the number of actual human cells. Thus, various interactions between microbes and human cells constitute an inevitable phenomenon. Recent evidence has led to bacterial extracellular RNAs (exRNAs) being proposed as good candidates for microbe-host inter-kingdom communication tools as they can modulate the expression of host genes. However, research findings on the relevance of interactions between extracellular RNA and human diseases are still in their infancy. Nevertheless, substantial data suggest that microbial exRNAs are implicated in various human diseases both at local and distant sites. By exploring various scenarios for the involvement of microbial exRNAs in human diseases, we may better understand the role of exRNAs as "communication signals" for diseases and thereby develop novel therapeutic strategies by using them and their carrier extracellular vesicles.

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.

The Effect of Mesenchymal Stem Cell-Derived Microvesicles on Erythroid Differentiation of Umbilical Cord Blood-Derived CD34+ Cells

Purpose: Mesenchymal stem cells (MSCs) play an important role in the proliferation and differentiation of hematopoietic stem cells (HSCs) in the bone marrow via cell-to-cell contact, as well as secretion of cytokines and microvesicles (MVs). In this study, we investigated the effect of mesenchymal stem cell-derived microvesicles (MSC-MVs) on erythroid differentiation of umbilical cord blood-derived CD34⁺ cells.

Methods: In this descriptive study, CD34⁺ cells were cultured with mixture of SCF (10 ng/ml) and rhEPO (5 U/ml) cytokines in complete IMDM medium as positive control group. Then, in MV1- and MV2-groups, microvesicles at 10 and 20 µg/ml concentration were added. After 72 hours, erythroid specific markers (CD71 and CD235a) and genes (HBG1, GATA1, FOG1 and NFE2) were assessed by flow cytometry and qRT-PCR, respectively.

Results: The expression of specific markers of the erythroid lineages (CD71 and GPA) in the presence of different concentration of microvesicles were lower than that of the control group (P<0.001). Also, the expression of specific genes of the erythroid lineages (NFE2, FOG1, GATA1, and HBG1) was investigated in comparison to the internal control (GAPDH). Among all of them, HBG1 and FOG1 genes were significantly decreased to the control group (P<0.0001) but GATA1 and NFE2 gene expressions was not significant.

Conclusion: The results of this study showed that MSC-MVs decrease the erythroid differentiation of umbilical cord blood-derived CD34⁺ cells. Therefore, MSC-MVs play a key role in the regulation of normal erythropoiesis.