The developing role of extracellular vesicles in autoimmune diseases: special attention to mesenchymal stem cell-derived extracellular vesicles.

Autoimmune diseases are complex, chronic inflammatory conditions initiated by the loss of immunological tolerance to self-antigens. Nowadays, there is no effective and useful therapy for autoimmune diseases, and the existing medications have some limitations due to their nonspecific targets and side effects. During the last few decades, it has been established that mesenchymal stem cells (MSCs) have immunomodulatory functions. It is proposed that MSCs can exert an important therapeutic effect on autoimmune disorders. In parallel with these findings, several investigations have shown that MSCs alleviate autoimmune diseases. Intriguingly, the results of studies have demonstrated that the effective roles of MSCs in autoimmune diseases do not depend on direct intercellular communication but on their ability to release a wide spectrum of paracrine mediators such as growth factors, cytokines and extracellular vehicles (EVs). EVs that range from 50 to 5,000 nm were produced by almost any cell type, and these nanoparticles participate in homeostasis and intercellular communication via the transfer of a broad range of biomolecules such as modulatory proteins, nucleic acids (DNA and RNA), lipids, cytokines, and metabolites. EVs derived from MSCs display the exact properties of MSCs and can be safer and more beneficial than their parent cells. In this review, we will discuss the features of MSCs and their EVs, EVs biogenesis, and their cargos, and then we will highlight the existing discoveries on the impacts of EVs from MSCs on autoimmune diseases such as multiple sclerosis, arthritis rheumatic, inflammatory bowel disease, Type 1 diabetes mellitus, systemic lupus erythematosus, autoimmune liver diseases, Sjögren syndrome, and osteoarthritis, suggesting a potential alternative for autoimmune conditions therapy.

PCSK9 pathway-noncoding RNAs crosstalk: Emerging opportunities for novel therapeutic approaches in inflammatory atherosclerosis.

A variety of mechanisms contribute to the occurrence and development of inflammatory atherosclerosis (IA), resulting in cardiovascular disease. PCSK9 (proprotein convertase subtilisin/ kexin type 9) has now been recognized as a key player in the pathophysiology of atherosclerosis. Following PCSK9 activation, LDL receptors (LDLR) are degraded and as a result, LDL cholesterol (LDLC) levels are increased. Increasing evidence reports that the PCSK9 axis mediates IA through different pathways, such as LDLR, LOX1, NF-kB, and TLR4. In recent years, PCSK9 pathway dysregulation has been identified as one of the fundamental mechanisms involved in IA. Recently, the importance of epigenetic factors, in particular, in non-coding RNAs, including miRNAs and long ncRNAs (lncRNAs) as well as circular RNAs (circRNAs) in the regulation of physiological and pathological events has received great attention. In this regard, an expanding body of research has revealed that different ncRNAs play important roles in the progression of inflammatory atherosclerosis through targeting genes related to the PCSK9 pathway at the post-transcriptional level. Of importance, the current study aimed to review the relationship between the various ncRNAs and PCSK9 pathway to identify the molecular mechanisms underlying IA pathogenesis as well as to introduce the novel PCSK9 pathway-related therapeutic interventions in combating IA.

P53 long noncoding RNA regulatory network in cancer development.

The protein p53 as a transcription factor with strong tumor-suppressive activities is known to trigger apoptosis via multiple pathways and is directly involved in the recognition of DNA damage and DNA repair processes. P53 alteration is now recognized as a common event in the pathogenesis of many types of human malignancies. Deregulation of tumor suppressor p53 pathways plays an important role in the activation of cell proliferation or inactivation of apoptotic cell death during carcinogenesis and tumor progression. Mounting evidence indicates that the p53 status of tumors and also the regulatory functions of p53 may be relevant to the long noncoding RNAs (lncRNA)-dependent gene regulation programs. Besides coding genes, lncRNAs that do not encode for proteins are induced or suppressed by p53 transcriptional response and thus control cancer progression. LncRNAs also have emerged as key regulators that impinge on the p53 signaling network orchestrating global gene-expression profile. Studies have suggested that aberrant expression of lncRNAs as a molecular-genomic signature may play important roles in cancer biology. Accordingly, it is important to elucidate the mechanisms by which the crosstalk between lncRNAs and p53 occurs in the development of numerous cancers. Here, we review how several classes of lncRNAs and p53 pathways are linked together in controlling the cell cycle and apoptosis in various cancer cells in both human and mouse model systems.