Genome-wide discovery and characterization of long noncoding RNAs in patients with multiple myeloma

The Landscape of lncRNAs in Multiple Myeloma: Implications in the "Hallmarks of Cancer", Clinical Perspectives and Therapeutic Opportunities

Simple Summary

Multiple myeloma (MM) is an aggressive hematological neoplasia caused by the uncontrolled proliferation of aberrant plasmacells. Neoplastic transformation and progression are driven by a number of biological processes, called ‘hallmarks of cancer’, which are regulated by different molecules, including long non-coding RNAs. A deeper understanding of the mechanisms that regulate MM development and progression will help to improve patients stratification and management, and promote the identification of new therapeutic targets.

Abstract

Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides that are not translated into proteins. Nowadays, lncRNAs are gaining importance as key regulators of gene expression and, consequently, of several biological functions in physiological and pathological conditions, including cancer. Here, we point out the role of lncRNAs in the pathogenesis of multiple myeloma (MM). We focus on their ability to regulate the biological processes identified as “hallmarks of cancer” that enable malignant cell transformation, early tumor onset and progression. The aberrant expression of lncRNAs in MM suggests their potential use as clinical biomarkers for diagnosis, patient stratification, and clinical management. Moreover, they represent ideal candidates for therapeutic targeting.

Knockdown of long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 protects against intracerebral hemorrhage through microRNA-146a-mediated inhibition of inflammation and oxidative stress

Studies have demonstrated that long noncoding RNAs (lncRNAs) are important regulators of intracerebral hemorrhage (ICH) and participants in ICH pathogenesis. We designed this study to probe the potential functions and mechanisms of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in ICH. The ICH model was established and the rats were treated with MALAT1-shRNA or MALAT1-shRNA+miR-146a inhibitor 1 h after ICH induction. A dual-luciferase reporter assay was employed to examine the relationship between MALAT1 and miR-146a. In addition, rat neurobehavioral changes, brain water content, and neuronal apoptosis were measured in this study. Furthermore, the pro‑inflammatory markers tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β were determined by enzyme-linked immunosorbent assays (ELISAs), while the oxidative stress factors, including malondialdehyde (MDA) and superoxide dismutase (SOD), were also evaluated. Lastly, a Western blot assay was employed to examine the protein levels of phosphorylated (p)-p65 and p65. First, we found that MALAT1 was expressed at higher levels in ICH rats. miR-146a is a target gene of MALAT1 and is downregulated in ICH rats. Downregulation of MALAT1 inhibited the neurological scores, brain water content, and neuronal apoptosis, reduced the levels of pro-inflammatory cytokines, and prevented oxidative stress in ICH rats. In addition, the protein level of p-p65 and the ratio of p-p65/p65 were decreased in the MALAT1-shRNA group. All the effects of MALAT1-shRNA on ICH rats were reversed by miR-146a inhibitor co-treatment. In conclusion, downregulation of MALAT1 protected against ICH by suppressing inflammation and oxidative stress by upregulating miR-146a.

LncRNAs LY86-AS1 and VIM-AS1 Distinguish Plasma Cell Leukemia Patients from Multiple Myeloma Patients

Long non-coding RNAs (lncRNAs) are functional RNAs longer than 200 nucleotides. Due to modern genomic techniques, the involvement of lncRNAs in tumorigenesis has been revealed; however, information concerning lncRNA interplay in multiple myeloma (MM) and plasma cell leukemia (PCL) is virtually absent. Herein, we aimed to identify the lncRNAs involved in MM to PCL progression. We investigated representative datasets of MM and PCL patients using next-generation sequencing. In total, 13 deregulated lncRNAs (p < 0.00025) were identified; four of them were chosen for further validation in an independent set of MM and PCL patients by RT-qPCR. The obtained results proved the significant downregulation of lymphocyte antigen antisense RNA 1 (LY86-AS1) and VIM antisense RNA 1 (VIM-AS1) in PCL compared to MM. Importantly, these two lncRNAs could be involved in the progression of MM into PCL; thus, they could serve as promising novel biomarkers of MM progression.

Novel Non-coding RNA Analysis in Multiple Myeloma Identified Through High-Throughput Sequencing

This study aimed to explore the potential effects of novel non-coding ribose nucleic acids (ncRNAs) in patients with multiple myeloma (MM). The gene expression profile of plasma cells was used for sequence analysis to explore the expression pattern of ncRNAs in MM. The expression patterns of non-coding RNAs in MM were analyzed by RNA sequencing (whole-transcriptome-specific RNA sequencing). Next, the expression of the selected ncRNAs was verified by quantitative real-time polymerase chain reaction. Further, the lncRNA-associated competitive endogenous RNA network in MM was elucidated using deep RNA-seq. Differentially expressed (DE) ncRNAs were significantly regulated in patients with MM. DE target lncRNAs were analyzed by cis and trans targeting prediction. Two new lncRNAs were shown to be related to MM oncogenes. MSTRG.155519 played a carcinogenic role in myeloma by targeting CEACAM1; MSTRG.13132 was related to FAM46C. Finally, the network of lncRNA–mRNA–miRNA in MM was constructed in this study. The expression of non-coding RNAs through sequence and functional analyses might be helpful for further studies on the pathogenesis of MM and the development of new MM-targeted therapy for non-coding RNAs.

Long non-coding RNA OIP5-AS1 suppresses multiple myeloma progression by sponging miR-27a-3p to activate TSC1 expression

BACKGROUND

Multiple myeloma (MM) is a prevalent hematological malignancy. Long noncoding RNAs are correlated with the development of MM. In this project, the function of lncRNA opa interacting protein 5-antisense 1 (OIP5-AS1) in MM and the potential mechanistic pathway were explored.

METHODS

The expression of OIP5-AS1, microRNA (miR)-27a-3p and tuberous sclerosis 1 (TSC1) was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) assay. Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) assay, colony formation assay and Bromodeoxyuridine (BrdU) staining. And cell apoptosis was evaluated by flow cytometry assay. Cell metastasis was assessed utilizing transwell assay. Western blot analysis was employed to detect protein level. The target relation between miR-27a-3p and OIP5-AS1 or TSC1 was confirmed via dual-luciferase reporter assay and RNA immunoprecipitation assay. Tumor xenograft assay was conducted to measure the function of OIP5-AS1 in vivo.

RESULTS

The expression levels of OIP5-AS1 and TSC1 were decreased in MM, whereas miR-27a-3p was upregulated. High level of OIP5-AS1 could predict favourable prognosis of MM patients. Overexpression of OIP5-AS1 inhibited cell viability, colony formation ability, migration and invasion, induced cell cycle arrest in G1 phase and apoptosis of MM cells in vitro as well as repressed tumorigenesis in vivo. MiR-27a-3p was a target of OIP5-AS1, and reversed the impact of OIP5-AS1 on MM cells. MiR-27a-3p directly targeted TSC1. Silencing of miR-27a-3p repressed MM progression by elevating TSC1 expression. OIP5-AS1 upregulated TSC1 by sponging miR-27a-3p.

CONCLUSION

OIP5-AS1 repressed multiple myeloma progression by regulating miR-27a-3p/TSC1 axis.