lncRNA requirements for mouse acute myeloid leukemia and normal differentiation

Machine learning-based integration develops a disulfidptosis-related lncRNA signature for improving outcomes in gastric cancer

Gastric cancer remains one of the deadliest cancers globally due to delayed detection and limited treatment options, underscoring the critical need for innovative prognostic methods. Disulfidptosis, a recently discovered programmed cell death triggered by disulphide stress, presents a fresh avenue for therapeutic exploration. This research examines disulfidptosis-related long noncoding RNAs (DRLs) in gastric cancer, with the goal of leveraging these lncRNAs as potential markers to enhance patient outcomes and treatment approaches. Comprehensive genomic and clinical data from stomach adenocarcinoma (STAD) were obtained from The Cancer Genome Atlas (TCGA). Employing least absolute shrinkage and selection operator (LASSO) regression analysis, a prognostic model was devised incorporating five key DRLs to forecast survival rates. The effectiveness of this model was validated using Kaplan-Meier survival plots, receiver operating characteristic (ROC) curves, and extensive functional enrichment studies. The importance of select lncRNAs and the expression variability of genes tied to disulfidptosis were validated via quantitative real-time PCR (qRT-PCR) and Western blot tests, establishing a solid foundation for their prognostic utility. Analyses of functional enrichment and tumour mutation burden highlighted the biological importance of these DRLs, connecting them to critical cancer pathways and immune responses. These discoveries broaden our comprehension of the molecular framework of gastric cancer and bolster the development of tailored treatment plans, highlighting the substantial role of DRLs in clinical prognosis and therapeutic intervention.

Emerging Roles of Long Non-Coding RNAs in Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Over the past decade, studies have demonstrated that circulating long non-coding RNAs (lncRNAs)-recognised for their stability and ease of detection-serve as crucial regulators and potential biomarkers in multiple diseases. LncRNAs regulate key processes, including endothelial function, vascular remodelling, and myocardial hypertrophy, all of which influence CVD progression. Additionally, lncRNAs display cell-, tissue-, and disease-specific expression patterns, making them ideal therapeutic targets or tools. This review presents a comprehensive overview of the current understanding of lncRNAs in CVDs, examining their mechanisms of action and recent research advances. It also addresses the use of lncRNAs as diagnostic and prognostic markers, as well as potential applications of RNA therapeutics in novel treatment strategies.

A review of the complex interplay between chemoresistance and lncRNAs in lung cancer

Lung Cancer (LC) is characterized by chemoresistance, which poses a significant clinical challenge and results in a poor prognosis for patients. Long non-coding RNAs (lncRNAs) have recently gained recognition as crucial mediators of chemoresistance in LC. Through the regulation of key cellular processes, these molecules play important roles in the progression of LC and response to therapy. The mechanisms by which lncRNAs affect chemoresistance include the modulation of gene expression, chromatin structure, microRNA interactions, and signaling pathways. Exosomes have emerged as key mediators of lncRNA-driven chemoresistance, facilitating the transfer of resistance-associated lncRNAs between cancer cells and contributing to tumor development. Consequently, exosomal lncRNAs may serve as biomarkers and therapeutic targets for the treatment of LC. Therapeutic strategies targeting lncRNAs offer novel approaches to circumvent chemoresistance. Different approaches, including RNA interference (RNAi) and antisense oligonucleotides (ASOs), are available to degrade lncRNAs or alter their function. ASO-based therapies are effective at reducing lncRNA expression levels, increasing chemotherapy sensitivity, and improving clinical outcomes. The use of these strategies can facilitate the development of targeted interventions designed to disrupt lncRNA-mediated mechanisms of chemoresistance. An important aspect of this review is the discussion of the complex relationship between lncRNAs and drug resistance in LC, particularly through exosomal pathways, and the development of innovative therapeutic strategies to enhance drug efficacy by targeting lncRNAs. The development of new pathways and interventions for treating LC holds promise in overcoming this resistance.

Effect of lncRNA XIST on acute myeloid leukemia cells via miR-142-5p-PFKP axis

Acute myeloid leukemia (AML) is the common blood cancer in hematopoietic system-related diseases and has a poor prognosis. Studies have shown that long non-coding RNAs (lncRNAs) are closely related to the pathogenesis of a variety of diseases, including AML. However, the specific molecular mechanism remains unclear. Hence, the objective of this study was to investigate the effect and mechanism of lncRNA X inactive specific transcript (lncRNA XIST) on AML. To achieve our objective, some tests were performed. Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect the expression of lncRNA XIST, miR-142-5p and the platelet isoform of phosphofructokinase (PFKP). The targeting relationship between miR-142-5p and lncRNA XIST and PFKP was verified by Pearson correlation analysis, dual-luciferase reporter assay, and pull-down assay. Functional experiments were used to analyze the effect and mechanism of action of knocking down lncRNA XIST on THP-1 and U937 cells. Compared with bone marrow cells, lncRNA XIST and PFKP expression levels were up-regulated and miR-142-5p expression levels were down-regulated in AML. Further analysis revealed that lncRNA XIST targeted and bound to miR-142-5p, and PFKP was a target gene of miR-142-5p. Knockdown of lncRNA XIST significantly promoted miR-142-5p expression to down-regulate PFKP in THP-1 and U937 cells, while the cell proliferation, cell viability, and cell cycle arrest were inhibited and apoptosis was increased. Knockdown of miR-142-5p reversed the functional impact of lncRNA XIST knockdown on AML cells. In conclusion, down-regulation of lncRNA XIST can affect the progression of AML by regulating miR-142-5p.

Expression of the long noncoding RNA CASC2 in acute myeloid leukemia and its prognostic significance

BACKGROUND

Cancer susceptibility candidate 2 (CASC2) was found underexpressed in multiple types of human malignancies. However, the specific role of CASC2 in AML remains uncertain. The purpose of this study is to explore the expression of CASC2 in patients with AML and healthy donors and its prognostic significance in AML.

METHODS

Total RNA was isolated from bone marrow samples or peripheral blood samples of 87 patients with AML and 26 healthy adult donors. The expression of long noncoding RNA CASC2 was detected by quantitative real-time polymerase chain reaction. The association between CASC2 expression and other clinicopathological factors as well as its prognosis significance were analyzed.

RESULTS

The peripheral blood mononuclear cell (PBMC) expression level of CASC2 in AML was significantly lower than that in the healthy control cohort (P = 0.0048), and in the bone marrow samples, CASC2 was significantly upregulated in patients with AML after the achievement of CR (median value: 0.041, range: 0.015-0.064) compared with that at newly diagnosis (median value: 0.017, range: 0.008-0.041) (P = 0.002). The expression of CASC2 had a significant relationship with complete remission (P = 0.019). Survival data assessed by Kaplan-Meier curves showed that patients with lower CASC2 expression had shorter overall survival and disease-free survival than patients with higher CASC2 expression. Finally, Cox proportional hazards analysis demonstrated that CASC2 was an independent prognostic indicator for both OS (P = 0.013) and DFS (P = 0.001) of AML.

CONCLUSIONS

LncRNA CASC2 may serve as a new molecular biomarker for the early diagnosis and of AML, and may be an independent prognostic factor affecting the survival of patients with AML.

Deciphering Transcriptomic Variations in Hematopoietic Lineages: HSCs, EBs, and MKs

In the realm of hematopoiesis, hematopoietic stem cells (HSCs) serve as pivotal entities responsible for generating various blood cell types, initiating both the myeloid and lymphoid branches within the hematopoietic lineage. This intricate process is marked by genetic variations that underscore the crucial role of genes in regulating cellular functions and interactions. Recognizing the significance of genetic factors in this context, this article delves into a genetic perspective, aiming to unravel the biological factors that govern the transition from one cell's fate to another within the hematopoietic system. To gain deeper insights into the genetic traits of three distinct blood cell types-HSCs, erythroblasts (EBs), and megakaryocytes (MKs)-we conducted a comprehensive transcriptomic analysis. Leveraging diverse hematopoietic cell datasets from healthy individuals, sourced from The BLUEPRINT consortium, our investigation targeted the identification of genetic variants responsible for changes in gene expression levels and epigenetic modifications across the entire human genome in each of these cell types. The total number of normalized expressed transcripts includes 14,233 novel trinity lncRNAs, 13,749 mRNAs, and 3092 lncRNAs. This scrutiny revealed a total of 31,074 transcripts, with a notable revelation that 14,233 of them were previously unidentified or novel lncRNAs, highlighting a substantial reservoir of genetic information yet to be explored. Examining their expression across distinct lineages further unveiled 2845 differentially expressed (DE) mRNAs and 354 DE long noncoding RNAs (lncRNAs) notably enriched among the three distinct blood cell types: HSCs, EBs, and MKs. Our investigation extended beyond mRNA to focus on the dynamic expression of lncRNAs, revealing a well-defined pattern that played a significant role in regulating differentiation and cell-fate specification. This coordination of lncRNA dynamics extended to aberrations in both mRNA and lncRNA transcriptomes within HSCs, EBs, and MKs. We specifically characterized lncRNAs with preferential expression in HSCs, as well as in various downstream differentiated lineage progenitors of EBs and MKs, providing a comprehensive perspective on lncRNAs in human hematopoietic cells. Notably, the expression of lncRNAs exhibited substantial cell-to-cell variation, a phenomenon discernible only through single-cell analysis. The comparative analysis undertaken in this study provides valuable insights into the distinctive genetic signatures guiding the differentiation of these crucial hematopoietic cell types.

Targeting and engineering long non-coding RNAs for cancer therapy

RNA therapeutics (RNATx) aim to treat diseases, including cancer, by targeting or employing RNA molecules for therapeutic purposes. Amongst the most promising targets are long non-coding RNAs (lncRNAs), which regulate oncogenic molecular networks in a cell type-restricted manner. lncRNAs are distinct from protein-coding genes in important ways that increase their therapeutic potential yet also present hurdles to conventional clinical development. Advances in genome editing, oligonucleotide chemistry, multi-omics and RNA engineering are paving the way for efficient and cost-effective lncRNA-focused drug discovery pipelines. In this Review, we present the emerging field of lncRNA therapeutics for oncology, with emphasis on the unique strengths and challenges of lncRNAs within the broader RNATx framework. We outline the necessary steps for lncRNA therapeutics to deliver effective, durable, tolerable and personalized treatments for cancer.

A 69 long noncoding RNA signature predicts relapse and acts as independent prognostic factor in pediatric AML

ABSTRACT

Risk stratification using genetics and minimal residual disease has allowed for an increase in the cure rates of pediatric acute myeloid leukemia (pedAML) to up to 70% in contemporary protocols. Nevertheless, ∼30% of patients still experience relapse, indicating a need to optimize stratification strategies. Recently, long noncoding RNA (lncRNA) expression has been shown to hold prognostic power in multiple cancer types. Here, we aimed at refining relapse prediction in pedAML using lncRNA expression. We built a relapse-related lncRNA prognostic signature, named AMLlnc69, using 871 transcriptomes of patients with pedAML obtained from the Therapeutically Applicable Research to Generate Effective Treatments repository. We identified a 69 lncRNA signature AMLlnc69 that is highly predictive of relapse risk (c-index = 0.73), with area under the receiver operating characteristic curve (AUC) values for predicting the 1-, 2-, and 3-year relapse-free survival (RFS) of 0.78, 0.77, and 0.77, respectively. The internal validation using a bootstrap method (resampling times = 1000) resulted in a c-index of 0.72 and AUC values for predicting the 1-, 2-, and 3-year RFS of 0.77, 0.76, and 0.76, respectively. Through a Cox regression analysis, AMLlnc69, nucleophosmin mutation, and white blood cell at diagnosis were identified as independent predictors of RFS. Finally, a nomogram was build using these 2 parameters, showing a c-index of 0.80 and 0.71 after bootstrapping (n = 1000). In conclusion, the identified AMLlnc69 will, after prospective validation, add important information to guide the management of patients with pedAML. The nomogram is a promising tool for easy stratification of patients into a novel scheme of relapse-risk groups.

MIAT LncRNA: A multifunctional key player in non-oncological pathological conditions

The discovery of non-coding RNAs (ncRNAs) has unveiled a wide range of transcripts that do not encode proteins but play key roles in several cellular and molecular processes. Long noncoding RNAs (lncRNAs) are specific class of ncRNAs that are longer than 200 nucleotides and have gained significant attention due to their diverse mechanisms of action and potential involvement in various pathological conditions. In the current review, the authors focus on the role of lncRNAs, specifically highlighting the Myocardial Infarction Associated Transcript (MIAT), in non-oncological context. MIAT is a nuclear lncRNA that has been directly linked to myocardial infarction and is reported to control post-transcriptional processes as a competitive endogenous RNA (ceRNA) molecule. It interacts with microRNAs (miRNAs), thereby limiting the translation and expression of their respective target messenger RNA (mRNA) and regulating protein expression. Yet, MIAT has been implicated in other numerous pathological conditions such as other cardiovascular diseases, autoimmune disease, neurodegenerative diseases, metabolic diseases, and many others. In this review, the authors emphasize that MIAT exhibits distinct expression patterns and functions across different pathological conditions and is emerging as potential diagnostic, prognostic, and therapeutic agent. Additionally, the authors highlight the regulatory role of MIAT and shed light on the involvement of lncRNAs and specifically MIAT in various non-oncological pathological conditions.

Long non-coding RNA CCAT1 acts as an oncogene to promote radiation resistance in lung adenocarcinoma: an epigenomics-based investigation

Long non-coding RNAs (lncRNAs) appear to be the crucial modulators in various processes and critically influence the oncogenesis. As one of the LncRNAs, LncRNA CCAT1 has been reported to be closely associated with the progression multiple cancers, but its role in modulating the radioresistance of lung adenocarcinoma (LUAD) remains unclear. In our present study, we screened the potential radioresistance related LncRNAs in LUAD based on the data from The Cancer Genome Atlas (TCGA) database. Data suggested that CCAT1 was abundantly expressed in LUAD and CCAT1 was significantly associated with poor prognosis and radioresistance. Moreover, our in vitro experiments showed that radiation treatment could trigger elevated expression of CCAT1 in the human LUAD cell lines. Further loss/gain-of-function investigations indicated that CCAT1 knockdown significantly inhibited cell proliferation, migration and promoted cell apoptosis in NCI-H1299 cells under irradiation, whereas CCAT1 overexpression in A549 cells yield the opposite effects. In summary, we identified the promoting role of CCAT1 in radioresistance of LUAD, which may provide a theoretical basis for radiotherapy sensitization of LUAD.

The ncBAF Complex Regulates Transcription in AML Through H3K27ac Sensing by BRD9

The non-canonical BAF complex (ncBAF) subunit BRD9 is essential for acute myeloid leukemia (AML) cell viability but has an unclear role in leukemogenesis. Because BRD9 is required for ncBAF complex assembly through its DUF3512 domain, precise bromodomain inhibition is necessary to parse the role of BRD9 as a transcriptional regulator from that of a scaffolding protein. To understand the role of BRD9 bromodomain function in regulating AML, we selected a panel of five AML cell lines with distinct driver mutations, disease classifications, and genomic aberrations and subjected these cells to short-term BRD9 bromodomain inhibition. We examined the bromodomain-dependent growth of these cell lines, identifying a dependency in AML cell lines but not HEK293T cells. To define a mechanism through which BRD9 maintains AML cell survival, we examined nascent transcription, chromatin accessibility, and ncBAF complex binding genome-wide after bromodomain inhibition. We identified extensive regulation of transcription by BRD9 bromodomain activity, including repression of myeloid maturation factors and tumor suppressor genes, while standard AML chemotherapy targets were repressed by inhibition of the BRD9 bromodomain. BRD9 bromodomain activity maintained accessible chromatin at both gene promoters and gene-distal putative enhancer regions, in a manner that qualitatively correlated with enrichment of BRD9 binding. Furthermore, we identified reduced chromatin accessibility at GATA, ETS, and AP-1 motifs and increased chromatin accessibility at SNAIL-, HIC-, and TP53-recognized motifs after BRD9 inhibition. These data suggest a role for BRD9 in regulating AML cell differentiation through modulation of accessibility at hematopoietic transcription factor binding sites.

SIGNIFICANCE

The bromodomain-containing protein BRD9 is essential for AML cell viability, but it is unclear whether this requirement is due to the protein's role as an epigenetic reader. We inhibited this activity and identified altered gene-distal chromatin regulation and transcription consistent with a more mature myeloid cell state.

ANRIL: A Long Noncoding RNA in Age-related Diseases

The intensification of the aging population is often accompanied by an increase in agerelated diseases, which impair the quality of life of the elderly. The characteristic feature of aging is progressive physiological decline, which is the largest cause of human pathology and death worldwide. However, natural aging interacts in exceptionally complex ways within and between organs, but its underlying mechanisms are still poorly understood. Long non-coding RNA (lncRNA) is a type of noncoding RNA that exceeds 200 nucleotides in length and does not possess protein-coding ability. It plays a crucial role in the occurrence and development of diseases. ANRIL, also known as CDKN2B-AS1, is an antisense ncRNA located at the INK4 site. It can play a crucial role in agerelated disease progression by regulating single nucleotide polymorphism, histone modifications, or post-transcriptional modifications (such as RNA stability and microRNA), such as cardiovascular disease, diabetes, tumor, arthritis, and osteoporosis. Therefore, a deeper understanding of the molecular mechanisms of lncRNA ANRIL in age-related diseases will help provide new diagnostic and therapeutic targets for clinical practice.

LncRNA ABHD11-AS1 activates EGFR signaling to promote cervical cancer progression by preventing FUS-mediated degradation of ABHD11 mRNA

Cervical cancer is one of the most common gynecological cancers with high metastasis, poor prognosis and conventional chemotherapy. The long non-coding RNA (lncRNA) ABHD11 antisense RNA 1 (ABHD11-AS1) plays a vital role in tumorigenesis and is involved in cell proliferation, differentiation, and apoptosis. Especially for cervical cancer, the functions and mechanisms of ABHD11-AS1 are still undetermined. In this study, we explored the role and underlying mechanism of ABHD11-AS1 in cervical cancer. We found that ABHD11-AS1 is highly expressed in cervical cancer tissue. The roles of ABHD11-AS1 and EGFR have investigated the loss of function analysis and cell movability in SiHa and Hela cells. Knockdown of ABHD11-AS1 and EGFR significantly inhibited the proliferation, migration, and invasion and promoted apoptosis of SiHa and Hela cells by up-regulating p21 and Bax and down-regulating cyclin D1, Bcl2, MMP9, and Vimentin. ABHD11-AS1 knockdown could decrease the expression of EGFR. In addition, ABHD11-AS1 could regulate the EGFR signaling pathway, including p-EGFR, p-AKT, and p-ERK. Spearman's correlation analysis and cell experiments demonstrated that ABHD11 was highly expressed in tumor tissue and partially offset the effect of shABHD11-AS1 on the proliferation, migration, and invasion of SiHa and Hela cells. Then, RNA pulldown was used to ascertain the mechanisms of ABHD11-AS1 and FUS. ABHD11-AS1 inhibited ABHD11 mRNA degradation by bounding to FUS. A subcutaneous xenograft of SiHa cells was established to investigate the effect of ABHD11-AS1 in tumor tissue. Knockdown of ABDH11-AS1 inhibited tumor growth and decreased the tumor volume. ABHD11-AS1 knockdown inhibited the expression of Ki67 and Vimentin and up-regulated the expression of Tunel. Our data indicated that ABHD11-AS1 promoted cervical cancer progression by activating EGFR signaling, preventing FUS-mediated degradation of ABHD11 mRNA. Our findings provide novel insights into the potential role of lncRNA in cervical cancer therapy.

Predicting cervical lymph node metastasis in OSCC based on computed tomography imaging genomics

BACKGROUND

To investigate the correlation between computed tomography (CT) radiomic characteristics and key genes for cervical lymph node metastasis (LNM) in oral squamous cell carcinoma (OSCC).

METHODS

The region of interest was annotated at the edge of the primary tumor on enhanced CT images from 140 patients with OSCC and obtained radiomic features. Ribonucleic acid (RNA) sequencing was performed on pathological sections from 20 patients. the DESeq software package was used to compare differential gene expression between groups. Weighted gene co-expression network analysis was used to construct co-expressed gene modules, and the KEGG and GO databases were used for pathway enrichment analysis of key gene modules. Finally, Pearson correlation coefficients were calculated between key genes of enriched pathways and radiomic features.

RESULTS

Four hundred and eighty radiomic features were extracted from enhanced CT images of 140 patients; seven of these correlated significantly with cervical LNM in OSCC (p < 0.01). A total of 3527 differentially expressed RNAs were screened from RNA sequencing data of 20 cases. original_glrlm_RunVariance showed significant positive correlation with most long noncoding RNAs.

CONCLUSIONS

OSCC cervical LNM is related to the salivary hair bump signaling pathway and biological process. Original_glrlm_RunVariance correlated with LNM and most differentially expressed long noncoding RNAs.

Emerging role of transforming growth factor-β-regulated long non-coding RNAs in prostate cancer pathogenesis

Prostate cancer (PCa) is the most common malignancy in men. Despite aggressive therapy involving surgery and hormonal treatments, the recurrence and emergence of metastatic castration-resistant prostate cancer (CRPCa) remain a major challenge. Dysregulation of the transforming growth factor-β (TGF-β) signaling pathway is crucial to PCa development and progression. This also contributes to androgen receptor activation and the emergence of CRPC. In addition, TGF-β signaling regulates long non-coding RNA (lncRNA) expression in multiple cancers, including PCa. Here, we discuss the complex regulatory network of lncRNAs and TGF-β signaling in PCa and their potential applications in diagnosing, prognosis, and treating PCa. Further investigations on the role of lncRNAs in the TGF-β pathway will help to better understand PCa pathogenesis.

A novel lncRNA SNHG29 regulates EP300- related histone acetylation modification and inhibits FLT3-ITD AML development

Internal tandem duplication (ITD) mutations within the FMS-like tyrosine kinase-3 (FLT3) occur in up to 25% of acute myeloid leukemia (AML) patients and indicate a very poor prognosis. The role of long noncoding RNAs (lncRNAs) in FLT3-ITD AML progression remains unexplored. We identified a novel lncRNA, SNHG29, whose expression is specifically regulated by the FLT3-STAT5 signaling pathway and is abnormally down-regulated in FLT3-ITD AML cell lines. SNHG29 functions as a tumor suppressor, significantly inhibiting FLT3-ITD AML cell proliferation and decreasing sensitivity to cytarabine in vitro and in vivo models. Mechanistically, we demonstrated that SNHG29's molecular mechanism is EP300-binding dependent and identified the EP300-interacting region of SNHG29. SNHG29 modulates genome-wide EP300 genomic binding, affecting EP300-mediated histone modification and consequently influencing the expression of varies downstream AML-associated genes. Our study uncovers a novel molecular mechanism for SNHG29 in mediating FLT3-ITD AML biological behaviors through epigenetic modification, suggesting that SNHG29 could be a potential therapeutic target for FLT3-ITD AML.

Role of non‑coding RNAs in cartilage endplate (Review)

Cartilage endplate (CEP) degeneration is considered one of the major causes of intervertebral disc degeneration (IDD), which causes non-specific neck and lower back pain. In addition, several non-coding RNAs (ncRNAs), including long ncRNAs, microRNAs and circular RNAs have been shown to be involved in the regulation of various diseases. However, the particular role of ncRNAs in CEP remains unclear. Identifying these ncRNAs and their interactions may prove to be is useful for the understanding of CEP health and disease. These RNA molecules regulate signaling pathways and biological processes that are critical for a healthy CEP. When dysregulated, they can contribute to the development disease. Herein, studies related to ncRNAs interactions and regulatory functions in CEP are reviewed. In addition, a summary of the current knowledge regarding the deregulation of ncRNAs in IDD in relation to their actions on CEP cell functions, including cell proliferation, apoptosis and extracellular matrix synthesis/degradation is presented. The present review provides novel insight into the pathogenesis of IDD and may shed light on future therapeutic approaches.

A novel lncRNA DFRV plays a dual function in influenza A virus infection

Long noncoding RNAs (lncRNAs) have been associated with a variety of biological activities, including immune responses. However, the function of lncRNAs in antiviral innate immune responses are not fully understood. Here, we identified a novel lncRNA, termed dual function regulating influenza virus (DFRV), elevating in a dose- and time-dependent manner during influenza A virus (IAV) infection, which was dependent on the NFκB signaling pathway. Meanwhile, DFRV was spliced into two transcripts post IAV infection, in which DFRV long suppress the viral replication while DFRV short plays the opposite role. Moreover, DFRV regulates IL-1β and TNF-α via activating several pro-inflammatory signaling cascades, including NFκB, STAT3, PI3K, AKT, ERK1/2 and p38. Besides, DFRV short can inhibit DFRV long expression in a dose-dependent manner. Collectively, our studies reveal that DFRV may act as a potential dual-regulator to preserve innate immune homeostasis in IAV infection.

Long Non-Coding RNAs in Retinal Ganglion Cell Apoptosis

Traumatic optic neuropathy or other neurodegenerative diseases, including optic nerve transection, glaucoma, and diabetic retinopathy, can lead to progressive and irreversible visual damage. Long non-coding RNAs (lncRNAs), which belong to the family of non-protein-coding transcripts, have been linked to the pathogenesis, progression, and prognosis of these lesions. Retinal ganglion cells (RGCs) are critical for the transmission of visual information to the brain, damage to which results in visual loss. Apoptosis has been identified as one of the most essential modes of RGC death. Emerging evidence suggests that lncRNAs can regulate RGC degeneration by directly or indirectly modulating apoptosis-associated signaling pathways. This review presents a comprehensive overview of the role of lncRNAs in RGC apoptosis at transcriptional, post-transcriptional, translational, and post-translational levels, emphasizing on the potential mechanisms of action. The current limitations and future perspectives of exploring the connection between lncRNAs and RGC apoptosis have been summarized. Understanding the intricate molecular interaction network of lncRNAs and RGC apoptosis will open new avenues for the identification of novel diagnostic biomarkers, therapeutic targets, and molecules for prognostic evaluation of diseases related to RGC injury.

lncRNA-disease association prediction based on the weight matrix and projection score

With the development of medical science, long noncoding RNA (lncRNA), originally considered as a noise gene, has been found to participate in a variety of biological activities. Several recent studies have shown the involvement of lncRNA in various human diseases, such as gastric cancer, prostate cancer, lung cancer, and so forth. However, obtaining lncRNA-disease relationship only through biological experiments not only costs manpower and material resources but also gains little. Therefore, developing effective computational models for predicting lncRNA-disease association relationship is extremely important. This study aimed to propose an lncRNA-disease association prediction model based on the weight matrix and projection score (LDAP-WMPS). The model used the relatively perfect lncRNA-miRNA relationship data and miRNA-disease relationship data to predict the lncRNA-disease relationship. The integrated lncRNA similarity matrix and the integrated disease similarity matrix were established by fusing various methods to calculate the similarity between lncRNA and disease. This study improved the existing weight algorithm, applied it to the lncRNA-miRNA-disease triple network, and thus proposed a new lncRNA-disease weight matrix calculation method. Combined with the improved projection algorithm, the lncRNA-miRNA relationship and miRNA-disease relationship were used to predict the lncRNA-disease relationship. The simulation results showed that under the Leave-One-Out-Cross-Validation framework, the area under the receiver operating characteristic curve of LDAP-WMPS could reach 0.8822, which was better than the latest result. Taking adenocarcinoma and colorectal cancer as examples, the LDAP-WMPS model was found to effectively infer the lncRNA-disease relationship. The simulation results showed good prediction performance of the LDAP-WMPS model, which was an important supplement to the research of lncRNA-disease association prediction without lncRNA-disease relationship data.

New developments in non-exosomal and exosomal ncRNAs in coronary artery disease

Aim & methods: Non-exosomal and exosomal ncRNAs have been reported to be involved in the regulation of coronary artery disease (CAD). Therefore, to explore the biological effects of non-exosomal/exosomal ncRNAs in CAD, the authors searched for studies published in the last 3 years on these ncRNAs in CAD and summarized their functions and mechanisms. Results: The authors summarized 120 non-exosomal ncRNAs capable of regulating CAD progression. In clinical studies, 47 non-exosomal and nine exosomal ncRNAs were able to serve as biomarkers for the diagnosis of CAD. Conclusion: Non-exosomal/exosomal ncRNAs are not only able to serve as biomarkers for CAD diagnosis but can also regulate CAD progression through ceRNA mechanisms and are a potential target for early clinical intervention in CAD.

The Crucial Role of AR-V7 in Enzalutamide-Resistance of Castration-Resistant Prostate Cancer

Simple Summary

Androgen receptor splice variant 7 (AR-V7) has always been considered a key driver for triggering enzalutamide resistance of castration-resistant prostate cancer (CRPC). In recent years, both the homeostasis of AR-V7 protein and AR-V7’s relationship with LncRNAs have gained great attention with in-depth studies. Starting from protein stability and LncRNA, the paper discusses and summarizes the mechanisms and drugs that affect the CRPC patients’ sensitivity to enzalutamide by regulating the protein or transcriptional stability of AR-V7, hoping to provide therapeutic ideas for subsequent research to break through the CRPC therapeutic bottleneck.

Abstract

Prostate cancer (PCa) has the second highest incidence of malignancies occurring in men worldwide. The first-line therapy of PCa is androgen deprivation therapy (ADT). Nonetheless, most patients progress to castration-resistant prostate cancer (CRPC) after being treated by ADT. As a second-generation androgen receptor (AR) antagonist, enzalutamide (ENZ) is the current mainstay of new endocrine therapies for CRPC in clinical use. However, almost all patients develop resistance during AR antagonist therapy due to various mechanisms. At present, ENZ resistance (ENZR) has become challenging in the clinical treatment of CRPC. AR splice variant 7 (AR-V7) refers to a ligand-independent and constitutively active variant of the AR and is considered a key driver of ENZR in CRPC. In this review, we summarize the mechanisms and biological behaviors of AR-V7 in ENZR of CRPC to contribute novel insights for CRPC therapy.

Designing libraries for pooled CRISPR functional screens of long noncoding RNAs

Human and other genomes encode tens of thousands of long noncoding RNAs (lncRNAs), the vast majority of which remain uncharacterised. High-throughput functional screening methods, notably those based on pooled CRISPR-Cas perturbations, promise to unlock the biological significance and biomedical potential of lncRNAs. Such screens are based on libraries of single guide RNAs (sgRNAs) whose design is critical for success. Few off-the-shelf libraries are presently available, and lncRNAs tend to have cell-type-specific expression profiles, meaning that library design remains in the hands of researchers. Here we introduce the topic of pooled CRISPR screens for lncRNAs and guide readers through the three key steps of library design: accurate annotation of transcript structures, curation of optimal candidate sets, and design of sgRNAs. This review is a starting point and reference for researchers seeking to design custom CRISPR screening libraries for lncRNAs.

The role of non-coding RNA in the diagnosis and treatment of Helicobacter pylori-related gastric cancer, with a focus on inflammation and immune response

Helicobacter pylori (H. pylori) is one of the globally recognized causative factors of gastric cancer (GC). Currently, no definite therapy and drugs for H. pylori-related GC have been widely acknowledged although H. pylori infection could be eradicated in early stage. Inflammation and immune response are spontaneous essential stages during H. pylori infection. H pylori may mediate immune escape by affecting inflammation and immune response, leading to gastric carcinogenesis. As an important component of transcriptome, non-coding RNAs (ncRNAs) have been proven to play crucial roles in the genesis and development of H. pylori-induced GC. This review briefly described the effects of ncRNAs on H. pylori-related GC from the perspective of inflammation and immune response, as well as their association with inflammatory reaction and immune microenvironment. We aim to explore the potential of ncRNAs as markers for the early diagnosis, prognosis, and treatment of H. pylori-related GC. The ncRNAs involved in H. pylori-related GC may all hold promise as novel therapeutic targets for immunotherapy.

Increased long noncoding RNA LINK-A contributes to rheumatoid synovial inflammation and aggression

Fibroblast-like synoviocytes (FLSs) play a key role in controlling synovial inflammation and joint destruction in rheumatoid arthritis (RA). The contribution of long noncoding RNAs (lncRNAs) to RA is largely unknown. Here, we show that the lncRNA LINK-A, located mainly in cytoplasm, has higher-than-normal expression in synovial tissues and FLSs from patients with RA. Synovial LINK-A expression was positively correlated with the severity of synovitis in patients with RA. LINK-A knockdown decreased migration, invasion, and expression and secretion of matrix metalloproteinases and proinflammatory cytokines in RA FLSs. Mechanistically, LINK-A controlled RA FLS inflammation and invasion through regulation of tyrosine protein kinase 6–mediated and leucine-rich repeat kinase 2–mediated HIF-1α. On the other hand, we also demonstrate that LINK-A could bind with microRNA 1262 as a sponge to control RA FLS aggression but not inflammation. Our findings suggest that increased level of LINK-A may contribute to FLS-mediated rheumatoid synovial inflammation and aggression. LINK-A might be a potential therapeutic target for RA.

Long non-coding RNA LINC02446 suppresses the proliferation and metastasis of bladder cancer cells by binding with EIF3G and regulating the mTOR signalling pathway

Accumulating evidence has been obtained to understand the mechanisms of long non-coding RNAs (lncRNAs) in bladder cancer (BC). However, due to the recurrence and metastasis of BC, searching for lncRNAs that are related to prognosis and metastasis and exploring the pathogenesis of BC might provide new insights for the treatment of BC. In the present study, we used the TCGA and GEO databases and identified LINC02446 as associated with prognosis and differentially expressed in bladder cancer tissues and para-cancer tissues. Then, we found that LINC02446 could affect the proliferation, migration and invasion of BC cells. Additionally, we found that LINC02446 could bind to the EIF3G protein and regulate the protein stability of EIF3G and then inhibit the mTOR signalling pathway. In summary, all these findings show that LINC02446 might serve as a promising therapeutic target for BC intervention.

Development of siRNA-Loaded Lipid Nanoparticles Targeting Long Non-Coding RNA LINC01257 as a Novel and Safe Therapeutic Approach for t(8;21) Pediatric Acute Myeloid Leukemia

Standard of care therapies for children with acute myeloid leukemia (AML) cause potent off-target toxicity to healthy cells, highlighting the need to develop new therapeutic approaches that are safe and specific for leukemia cells. Long non-coding RNAs (lncRNAs) are an emerging and highly attractive therapeutic target in the treatment of cancer due to their oncogenic functions and selective expression in cancer cells. However, lncRNAs have historically been considered ‘undruggable’ targets because they do not encode for a protein product. Here, we describe the development of a new siRNA-loaded lipid nanoparticle for the therapeutic silencing of the novel oncogenic lncRNA LINC01257. Transcriptomic analysis of children with AML identified LINC01257 as specifically expressed in t(8;21) AML and absent in healthy patients. Using NxGen microfluidic technology, we efficiently and reproducibly packaged anti-LINC01257 siRNA (LNP-si-LINC01257) into lipid nanoparticles based on the FDA-approved Patisiran (Onpattro^®) formulation. LNP-si-LINC01257 size and ζ-potential were determined by dynamic light scattering using a Malvern Zetasizer Ultra. LNP-si-LINC01257 internalization and siRNA delivery were verified by fluorescence microscopy and flow cytometry analysis. lncRNA knockdown was determined by RT-qPCR and cell viability was characterized by flow cytometry-based apoptosis assay. LNP-siRNA production yielded a mean LNP size of ~65 nm with PDI ≤ 0.22 along with a >85% siRNA encapsulation rate. LNP-siRNAs were efficiently taken up by Kasumi-1 cells (>95% of cells) and LNP-si-LINC01257 treatment was able to successfully ablate LINC01257 expression which was accompanied by a significant 55% reduction in total cell count following 48 h of treatment. In contrast, healthy peripheral blood mononuclear cells (PBMCs), which do not express LINC01257, were unaffected by LNP-si-LINC01257 treatment despite comparable levels of LNP-siRNA uptake. This is the first report demonstrating the use of LNP-assisted RNA interference modalities for the silencing of cancer-driving lncRNAs as a therapeutically viable and non-toxic approach in the management of AML.

Long noncoding RNAs: Emerging regulators of normal and malignant hematopoiesis

Genome wide analyses have revealed that long-noncoding RNAs (lncRNAs) are not only passive transcription products, but also major regulators of genome structure and transcription. In particular, lncRNAs exert profound effects on various biological processes, such as chromatin structure, transcription, RNA stability and translation, and protein degradation and localization, which depend on their localization and interacting partners. Recent studies have revealed that thousands of lncRNAs are aberrantly expressed in various cancer types and some of them are associated with malignant transformation. Despite extensive efforts, the diverse functions of lncRNAs and molecular mechanisms in which they act remain elusive. Many hematological disorders and malignancies are primarily resulted from genetic alterations that lead to the dysregulation of gene regulatory networks required for cellular proliferation and differentiation. Consequently, a growing list of lncRNAs has been reported for their involvement in the modulation of hematopoietic gene expression networks and hematopoietic stem and progenitor cell (HS/PC) function. Dysregulation of some of these lncRNAs has been attributed to pathogenesis of hematological malignancies. In this review, we will summarize current advances and knowledge of lncRNAs in gene regulation, focusing on the recent progresses on the role of lncRNAs in CTCF/cohesin mediated three-dimensional (3D) genome organization, and how such genome folding signals in turn regulate transcription, HS/PC function and transformation. The knowledge will provide mechanistic and translational insights into HS/PC biology and myeloid malignancy pathophysiology.

Identification of Potential Key lncRNAs in the Context of Mouse Myeloid Differentiation by Systematic Transcriptomics Analysis

Hematopoietic differentiation is a well-orchestrated process by many regulators such as transcription factor and long non-coding RNAs (lncRNAs). However, due to the large number of lncRNAs and the difficulty in determining their roles, the study of lncRNAs is a considerable challenge in hematopoietic differentiation. Here, through gene co-expression network analysis over RNA-seq data generated from representative types of mouse myeloid cells, we obtained a catalog of potential key lncRNAs in the context of mouse myeloid differentiation. Then, employing a widely used in vitro cell model, we screened a novel lncRNA, named Gdal1 (Granulocytic differentiation associated lncRNA 1), from this list and demonstrated that Gdal1 was required for granulocytic differentiation. Furthermore, knockdown of Cebpe, a principal transcription factor of granulocytic differentiation regulation, led to down-regulation of Gdal1, but not vice versa. In addition, expression of genes involved in myeloid differentiation and its regulation, such as Cebpa, were influenced in Gdal1 knockdown cells with differentiation blockage. We thus systematically identified myeloid differentiation associated lncRNAs and substantiated the identification by investigation of one of these lncRNAs on cellular phenotype and gene regulation levels. This study promotes our understanding of the regulation of myeloid differentiation and the characterization of roles of lncRNAs in hematopoietic system.

Long non-coding RNAs as novel therapeutic targets in juvenile myelomonocytic leukemia

Juvenile myelomonocytic leukemia (JMML) treatment primarily relies on hematopoietic stem cell transplantation and results in long-term overall survival of 50-60%, demonstrating a need to develop novel treatments. Dysregulation of the non-coding RNA transcriptome has been demonstrated before in this rare and unique disorder of early childhood. In this study, we investigated the therapeutic potential of targeting overexpressed long non-coding RNAs (lncRNAs) in JMML. Total RNA sequencing of bone marrow and peripheral blood mononuclear cell preparations from 19 untreated JMML patients and three healthy children revealed 185 differentially expressed lncRNA genes (131 up- and 54 downregulated). LNA GapmeRs were designed for 10 overexpressed and validated lncRNAs. Molecular knockdown (≥ 70% compared to mock control) after 24 h of incubation was observed with two or more independent GapmeRs in 6 of them. For three lncRNAs (lnc-THADA-4, lnc-ACOT9-1 and NRIR) knockdown resulted in a significant decrease of cell viability after 72 h of incubation in primary cultures of JMML mononuclear cells, respectively. Importantly, the extent of cellular damage correlated with the expression level of the lncRNA of interest. In conclusion, we demonstrated in primary JMML cell cultures that knockdown of overexpressed lncRNAs such as lnc-THADA-4, lnc-ACOT9-1 and NRIR may be a feasible therapeutic strategy.

LNCcation: lncRNA localization and function

Subcellular localization of RNAs has gained attention in recent years as a prevalent phenomenon that influences numerous cellular processes. This is also evident for the large and relatively novel class of long noncoding RNAs (lncRNAs). Because lncRNAs are defined as RNA transcripts >200 nucleotides that do not encode protein, they are themselves the functional units, making their subcellular localization critical to their function. The discovery of tens of thousands of lncRNAs and the cumulative evidence involving them in almost every cellular activity render assessment of their subcellular localization essential to fully understanding their biology. In this review, we summarize current knowledge of lncRNA subcellular localization, factors controlling their localization, emerging themes, including the role of lncRNA isoforms and the involvement of lncRNAs in phase separation bodies, and the implications of lncRNA localization on their function and on cellular behavior. We also discuss gaps in the current knowledge as well as opportunities that these provide for novel avenues of investigation.

Functional Screening Techniques to Identify Long Non-Coding RNAs as Therapeutic Targets in Cancer

Simple Summary

Long non-coding RNAs (lncRNAs) are a recently discovered class of molecules in the cell, with potential to be utilized as therapeutic targets in cancer. A number of lncRNAs have been described to play important roles in tumor progression and drive molecular processes involved in cell proliferation, apoptosis or invasion. However, the vast majority of lncRNAs have not been studied in the context of cancer thus far. With the advent of CRISPR/Cas genome editing, high-throughput functional screening approaches to identify lncRNAs that impact cancer growth are becoming more accessible. Here, we review currently available methods to study hundreds to thousands of lncRNAs in parallel to elucidate their role in tumorigenesis and cancer progression.

Abstract

Recent technological advancements such as CRISPR/Cas-based systems enable multiplexed, high-throughput screening for new therapeutic targets in cancer. While numerous functional screens have been performed on protein-coding genes to date, long non-coding RNAs (lncRNAs) represent an emerging class of potential oncogenes and tumor suppressors, with only a handful of large-scale screens performed thus far. Here, we review in detail currently available screening approaches to identify new lncRNA drivers of tumorigenesis and tumor progression. We discuss the various approaches of genomic and transcriptional targeting using CRISPR/Cas9, as well as methods to post-transcriptionally target lncRNAs via RNA interference (RNAi), antisense oligonucleotides (ASOs) and CRISPR/Cas13. We discuss potential advantages, caveats and future applications of each method to provide an overview and guide on investigating lncRNAs as new therapeutic targets in cancer.

Crosstalk Between MYC and lncRNAs in Hematological Malignancies

The human genome project revealed the existence of many thousands of long non-coding RNAs (lncRNAs). These transcripts that are over 200 nucleotides long were soon recognized for their importance in regulating gene expression. However, their poor conservation among species and their still controversial annotation has limited their study to some extent. Moreover, a generally lower expression of lncRNAs as compared to protein coding genes and their enigmatic biochemical mechanisms have impeded progress in the understanding of their biological roles. It is, however, known that lncRNAs engage in various kinds of interactions and can form complexes with other RNAs, with genomic DNA or proteins rendering their functional regulatory network quite complex. It has emerged from recent studies that lncRNAs exert important roles in gene expression that affect many cellular processes underlying development, cellular differentiation, but also the pathogenesis of blood cancers like leukemia and lymphoma. A number of lncRNAs have been found to be regulated by several well-known transcription factors including Myelocytomatosis viral oncogene homolog (MYC). The c-MYC gene is known to be one of the most frequently deregulated oncogenes and a driver for many human cancers. The c-MYC gene is very frequently activated by chromosomal translocations in hematopoietic cancers most prominently in B- or T-cell lymphoma or leukemia and much is already known about its role as a DNA binding transcriptional regulator. Although the understanding of MYC's regulatory role controlling lncRNA expression and how MYC itself is controlled by lncRNA in blood cancers is still at the beginning, an intriguing picture emerges indicating that c-MYC may execute part of its oncogenic function through lncRNAs. Several studies have identified lncRNAs regulating c-MYC expression and c-MYC regulated lncRNAs in different blood cancers and have unveiled new mechanisms how these RNA molecules act. In this review, we give an overview of lncRNAs that have been recognized as critical in the context of activated c-MYC in leukemia and lymphoma, describe their mechanism of action and their effect on transcriptional reprogramming in cancer cells. Finally, we discuss possible ways how an interference with their molecular function could be exploited for new cancer therapies.

Long non-coding RNAs and MYC association in hematological malignancies

Long non-coding RNAs (lncRNAs) have an established role in cell biology. Among their functions is the regulation of hematopoiesis. They characterize the different stages of hematopoiesis in a more lineage-restricted expression pattern than coding mRNAs. They affect hematopoietic stem cell renewal, proliferation, and differentiation of committed progenitors by interacting with master regulators transcription factors. Among these transcription factors, MYC has a prominent role. Similar to MYC's transcriptional activation/amplification of protein coding genes, MYC also regulates lncRNAs' expression profile, while it is also regulated by lncRNAs. Both myeloid and lymphoid malignancies are prone to the association of MYC with lncRNAs. Such interaction inhibits apoptosis, enhances cell proliferation, deregulates metabolism, and promotes genomic instability and resistance to treatment. In this review, we discuss the recent findings that encompass the crosstalk between lncRNAs and describe the pathways that very probably have a pathogenetic role in both acute and chronic hematologic malignancies.

Long non-coding RNA LINC01268 promotes cell growth and inhibits cell apoptosis by modulating miR-217/SOS1 axis in acute myeloid leukemia

The aim of this study was to evaluate the pathogenic role of newly identified long non-coding (lnc)-RNA LINCO1268 in acute myeloid leukemia (AML), and investigate its therapeutic potential. The expression level of LINC01268 in AML was measured by quantitative PCR (qPCR). The viability, cell cycle progression, and apoptosis of AML cells were measured by CCK-8 assay and flow cytometry, respectively. The interaction between LINC01268 and miR-217 were predicted by the miRDB website, and then verified by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. The relationship between miR-217 and SOS1 was predicted by TargetScan website, and verified by luciferase reporter assay. LINC01268 was significantly upregulated by 1.6 fold in bone marrow samples of AML patients, which was associated with poor prognosis. LINC01268 was also significantly upregulated in AML cells. LINC01268 knockdown inhibited viability and cell cycle progression but promoted apoptosis of AML cells. Furthermore, LINC01268 functioned as a ceRNA via competitively binding to miR-217, and SOS1 was identified as a target of miR-217. Moreover, LINC01268 positively regulated SOS1 expression to promote AML cell viability and cell cycle progression but inhibited apoptosis via sponging miR-217. LINC01268 promoted cell growth and inhibited cell apoptosis through modulating miR-217/SOS1 axis in AML. This study offers a novel molecular mechanism for a better understanding of the pathology of AML. LINC01268 could be considered as a potential biomarker for the therapy and diagnosis of AML.

Reduce proliferation of human bone marrow cells from acute myeloblastic leukemia with minimally differentiation by blocking lncRNA PVT1

PURPOSE

Acute myeloblastic leukemia with minimally differentiation (AML-M0) is a subtype of acute leukemia with poor prognosis. The recent studies have shown that long non-coding RNAs (lncRNAs) play an important role in different cellular processes, such as cell cycle control and proliferation. Plasmacytoma variant translocation 1 (PVT1) is one of those lncRNAs that is significantly upregulated in AML. LncRNAs could be downregulated or blocked by locked nucleic acids (LNA) which are oligonucleotide strands.

METHODS

In this study, lncRNA PVT1 was blocked by antisense LNA GapmeRs in human bone marrow cancerous blast cells. Cells were transfected with PVT1 antisense LNA GapmeRs at 24, 48, and 72 h post-transfection. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was accomplished to evaluate the PVT1 and c-Myc expression. Cell viability was evaluated by MTT assay, and apoptosis and necrosis were assessed by Annexin V/propidium iodide staining assay.

RESULTS

The results of this study indicated that the downregulation of PVT1 in blast cells could induce apoptosis, and necrosis and reduce cell viability. The expression of c-Myc was downregulated by blockage of PVT1 and it shows that the expression of these two genes are correlated.

CONCLUSION

The findings declare that inhibition of PVT1 could be a new target in the treatment of AML-M0 and help to approach more to treatments with fewer side effects.

Linear and circular PVT1 in hematological malignancies and immune response: two faces of the same coin

Non coding RNAs (ncRNAs) have emerged as regulators of human carcinogenesis by affecting the expression of key tumor suppressor genes and oncogenes. They are divided into short and long ncRNAs, according to their length. Circular RNAs (circRNAs) are included in the second group and were recently discovered as being originated by back-splicing, joining either single or multiple exons, or exons with retained introns. The human Plasmacytoma Variant Translocation 1 (PVT1) gene maps on the long arm of chromosome 8 (8q24) and encodes for 52 ncRNAs variants, including 26 linear and 26 circular isoforms, and 6 microRNAs. PVT1 genomic locus is 54 Kb downstream to MYC and several interactions have been described among these two genes, including a feedback regulatory mechanism. MYC-independent functions of PVT1/circPVT1 have been also reported, especially in the regulation of immune responses. We here review and discuss the role of both PVT1 and circPVT1 in the hematopoietic system. No information is currently available concerning their transforming ability in hematopoietic cells. However, present literature supports their cooperation with a more aggressive and/or undifferentiated cell phenotype, thus contributing to cancer progression. PVT1/circPVT1 upregulation through genomic amplification or rearrangements and/or increased transcription, provides a proliferative advantage to malignant cells in acute myeloid leukemia, acute promyelocytic leukemia, Burkitt lymphoma, multiple myeloma (linear PVT1) and acute lymphoblastic leukemia (circPVT1). In addition, PVT1 and circPVT1 regulate immune responses: the overexpression of the linear form in myeloid derived suppressor cells induced immune tolerance in preclinical tumor models and circPVT1 showed immunosuppressive properties in myeloid and lymphoid cell subsets. Overall, these recent data on PVT1 and circPVT1 functions in hematological malignancies and immune responses reflect two faces of the same coin: involvement in cancer progression by promoting a more aggressive phenotype of malignant cells and negative regulation of the immune system as a novel potential therapy-resistance mechanism.

LncRNA LINC00899 promotes progression of acute myeloid leukaemia by modulating miR-744-3p/YY1 signalling

Long non-coding RNA (lncRNA) LINC00899 is one kind cytoplasmic lncRNA, however, there is rarely little information about its function in physiological process. Here, we demonstrated that lncRNA LINC00899 was upregulated in acute myeloid leukaemia (AML) cells and was quite correlated with poor prognosis of AML patients. High expression of LINC00899 in AML cells could promote cell proliferation and inhibit cell apoptosis, and facilitate the progression of AML consequently both in vitro and in vivo. Besides, LINC00899 acted as a molecular sponge of miR-744-3p. Furthermore, we characterized YY1 as the direct target of miR-744-3p, and LINC00899/miR-744-3p interaction modulated YY1 expression in AML cells. Finally, we verified LINC00899 modulated AML cell proliferation and apoptosis via regulating YY1. Our study revealed novel mechanism about how did lncRNA LINC00899 execute function in AML and thus provided potential therapeutic interventions for AML. SIGNIFICANCE OF THE STUDY: LncRNA LINC00899 is upregulated in AML cells and is correlated with poor prognosis of AML patients. LncRNA LINC00899 mediates cell proliferation and apoptosis of acute myeloid leukaemia cells. Knockdown of LINC00899 inhibited the growth of xenograft glioma tumour in vivo. LINC00899 acts as a molecular sponge of miR-744-3p. YY1 is the downstream target of LINC00899/miR-744-3p signalling.

The potential influence of long non-coding RNA PRKG1-AS1 on oral squamous cell carcinoma: A comprehensive study based on bioinformatics and in vitro validation

BACKGROUND

Oral squamous cell carcinoma (OSCC) is one of the most frequent malignancies in oral cancer. Herein, we aimed to investigate the influence of lncRNA protein kinase cGMP-dependent type I-Antisense RNA 1 (PRKG1-AS1) in OSCC progression.

METHODS

Basing on the data acquired from TCGA database, the expression and prognostic value of PRKG1-AS1 in OSCC patients were assessed. The expression of PRKG1-AS1 in OSCC cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell growth was evaluated by Cell Counting Kit-8 (CCK8) and colony-forming assays. Transwell assay was employed to test cell invasion and migration. The protein expression of epithelial-mesenchymal transition (EMT)-related markers was detected by Western blotting.

RESULTS

The consequences displayed that PRKG1-AS1 was highly expressed in OSCC tissues and high expression of PRKG1-AS1 predicted poor outcomes. The expression of PRKG1-AS1 was higher in CAL27, SCC-9, and SCC-4 than that in normal human oral keratinocytes (NHOK). The results of biological experiments showed that deficiency of PRKG1-AS1 suppressed cell growth, invasion, and migration in CAL27 cells, and over-expression of PRKG1-AS1 accelerated cell growth, invasion, and migration in SCC-4 cells. Finally, silencing of PRKG1-AS1 obviously facilitated the protein expression levels of E-cadherin and reduced levels of N-cadherin, Vimentin, and Snail in CAL27 cells whereas over-expression of PRKG1-AS1 led to opposite results in SCC-4 cells.

CONCLUSION

These outcomes indicated that PRKG1-AS1 functioned as a facilitator in OSCC cell growth, migration, and invasion, which all might be achieved by regulating EMT.

Retracted Article: LncRNA ZEB2-AS1 regulates the drug resistance of acute myeloid leukemia via the miR-142-3p/INPP4B axis

Dysregulation of long noncoding RNAs (lncRNAs) has been reported to participate in the process of chemoresistance in multiple cancers, including acute myeloid leukemia (AML). LncRNA zinc finger E-box binding homeobox 2 antisense RNA 1 (ZEB2-AS1) has been reported to be up-regulated in AML. However, the biological role of ZEB2-AS1 remains to be determined. Quantitative real time polymerase chain reaction (qRT-PCR) was used to detect the levels of ZEB2-AS1, miR-142-3p and inositol polyphosphate-4-phosphatase type II B (INPP4B). The cell viability and apoptosis were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively. Western blotting was applied to analyze levels of BCL2 apoptosis regulator (Bcl-2), BCL2 associated X, apoptosis regulator (Bax), cleaved-caspase-3 and INPP4B. The interaction among ZEB2-AS1, miR-142-3p and INPP4B was verified by dual-luciferase reporter assay and RNA pull-down assay. The levels of ZEB2-AS1 and INPP4B were significantly elevated in AML and chemo-resistance tissues, as well as in THP-1 and THP-1/ADR cells. ZEB2-AS1 elevated the IC50 of ADR, and suppressed cell apoptosis of AML cells, while ZEB2-AS1 increased Bcl-2 expression and decreased the levels of Bax and cleaved-caspase-3. ZEB2-AS1 could enhance the resistance in THP-1 and THP-1/ADR cells. ZEB2-AS1 could sponge miR-142-3p, and ZEB2-AS1 reduced the promotion effect of miR-124-3p on the sensitivity of AML cells. Furthermore, IPNN4B was revealed as a target gene of miR-142-3p. More interestingly, suppression of IPNN4B by shRNA reversed the inhibitory effect of ZEB2-AS1 on the sensitivity of AML cells. LncRNA ZEB2-AS1 promoted ADR resistance of AML via regulating INP4B expression by sponging miR-142-3p, providing a novel therapeutic target for drug resistance of AML.

Long Noncoding RNAs in Acute Myeloid Leukemia: Functional Characterization and Clinical Relevance

Acute Myeloid Leukemia (AML) is the most common form of leukemia in adults with an incidence of 4.3 per 100,000 cases per year. Historically, the identification of genetic alterations in AML focused on protein-coding genes to provide biomarkers and to understand the molecular complexity of AML. Despite these findings and because of the heterogeneity of this disease, questions as to the molecular mechanisms underlying AML development and progression remained unsolved. Recently, transcriptome-wide profiling approaches have uncovered a large family of long noncoding RNAs (lncRNAs). Larger than 200 nucleotides and with no apparent protein coding potential, lncRNAs could unveil a new set of players in AML development. Originally considered as dark matter, lncRNAs have critical roles to play in the different steps of gene expression and thus affect cellular homeostasis including proliferation, survival, differentiation, migration or genomic stability. Consequently, lncRNAs are found to be differentially expressed in tumors, notably in AML, and linked to the transformation of healthy cells into leukemic cells. In this review, we aim to summarize the knowledge concerning lncRNAs functions and implications in AML, with a particular emphasis on their prognostic and therapeutic potential.

Xist RNA in action: Past, present, and future

In mammals, dosage compensation of sex chromosomal genes between females (XX) and males (XY) is achieved through X-chromosome inactivation (XCI). The X-linked X-inactive-specific transcript (Xist) long noncoding RNA is indispensable for XCI and initiates the process early during development by spreading in cis across the X chromosome from which it is transcribed. During XCI, Xist RNA triggers gene silencing, recruits a plethora of chromatin modifying factors, and drives a major structural reorganization of the X chromosome. Here, we review our knowledge of the multitude of epigenetic events orchestrated by Xist RNA to allow female mammals to survive through embryonic development by establishing and maintaining proper dosage compensation. In particular, we focus on recent studies characterizing the interaction partners of Xist RNA, and we discuss how they have affected the field by addressing long-standing controversies or by giving rise to new research perspectives that are currently being explored. This review is dedicated to the memory of Denise Barlow, pioneer of genomic imprinting and functional long noncoding RNAs (lncRNAs), whose work has revolutionized the epigenetics field and continues to inspire generations of scientists.

Role of non-coding RNA in pancreatic cancer

Pancreatic cancer is a malignant disease that develops rapidly and carries a poor prognosis. Currently, surgery is the only radical treatment. Non-coding RNAs (ncRNAs) are protein-free RNAs produced by genome transcription; they play important roles in regulating gene expression, participating in epigenetic modification, cell proliferation, differentiation and reproduction. ncRNAs also play key roles in the development of cancer; microRNA (miRNA) and long non-coding RNA (lncRNA) may lead the way to new treatments for pancreatic cancer. miRNAs are short-chain ncRNAs (19–24 nt) that inhibit the degradation of protein translation or their target gene mRNAs to regulate gene expression. lncRNAs contain >200 nt of ncRNA and play important regulatory roles in a number of malignant tumors, in terms of tumor cell proliferation, apoptosis, invasion and distant metastasis. lncRNAs can be exploited for the diagnosis and treatment of pancreatic cancer and have substantial prospects for clinical application. Nevertheless, the molecular mechanism of their regulation and function, as well as the significance of other ncRNAs, such as piwi-interacting RNA, in the pathogenesis of pancreatic cancer, are largely unknown. In this review, the structures of ncRNAs with various classifications, as well as the functions and important roles of ncRNAs in the diagnosis and treatment of pancreatic cancer are reviewed.

Not Only Mutations Matter: Molecular Picture of Acute Myeloid Leukemia Emerging from Transcriptome Studies

The last two decades of genome-scale research revealed a complex molecular picture of acute myeloid leukemia (AML). On the one hand, a number of mutations were discovered and associated with AML diagnosis and prognosis; some of them were introduced into diagnostic tests. On the other hand, transcriptome studies, which preceded AML exome and genome sequencing, remained poorly translated into clinics. Nevertheless, gene expression studies significantly contributed to the elucidation of AML pathogenesis and indicated potential therapeutic directions. The power of transcriptomic approach lies in its comprehensiveness; we can observe how genome manifests its function in a particular type of cells and follow many genes in one test. Moreover, gene expression measurement can be combined with mutation detection, as high-impact mutations are often present in transcripts. This review sums up 20 years of transcriptome research devoted to AML. Gene expression profiling (GEP) revealed signatures distinctive for selected AML subtypes and uncovered the additional within-subtype heterogeneity. The results were particularly valuable in the case of AML with normal karyotype which concerns up to 50% of AML cases. With the use of GEP, new classes of the disease were identified and prognostic predictors were proposed. A plenty of genes were detected as overexpressed in AML when compared to healthy control, including KIT, BAALC, ERG, MN1, CDX2, WT1, PRAME, and HOX genes. High expression of these genes constitutes usually an unfavorable prognostic factor. Upregulation of FLT3 and NPM1 genes, independent on their mutation status, was also reported in AML and correlated with poor outcome. However, transcriptome is not limited to the protein-coding genes; other types of RNA molecules exist in a cell and regulate genome function. It was shown that microRNA (miRNA) profiles differentiated AML groups and predicted outcome not worse than protein-coding gene profiles. For example, upregulation of miR-10a, miR-10b, and miR-196b and downregulation of miR-192 were found as typical of AML with NPM1 mutation whereas overexpression of miR-155 was associated with FLT3-internal tandem duplication (FLT3-ITD). Development of high-throughput technologies and microarray replacement by next generation sequencing (RNA-seq) enabled uncovering a real variety of leukemic cell transcriptomes, reflected by gene fusions, chimeric RNAs, alternatively spliced transcripts, miRNAs, piRNAs, long noncoding RNAs (lncRNAs), and their special type, circular RNAs. Many of them can be considered as AML biomarkers and potential therapeutic targets. The relations between particular RNA puzzles and other components of leukemic cells and their microenvironment, such as exosomes, are now under investigation. Hopefully, the results of this research will shed the light on these aspects of AML pathogenesis which are still not completely understood.

Elevated SPINK2 gene expression is a predictor of poor prognosis in acute myeloid leukemia

Acute myeloid leukemia (AML) has a high mortality rate and its clinical management remains challenging. The aim of the present study was to identify the hub genes involved in AML. In order to do so, the gene expression data of the GSE9476 database, including 26 AML and 10 normal samples, were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were then identified via bioinformatics analysis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed on DEGs. Furthermore, the most upregulated genes were selected for further investigation in the Oncomine, gene expression profiling interactive analysis and UALCAN datasets. In total, 1,744 upregulated and 1,956 downregulated genes were detected. The GO and KEGG results revealed that upregulated genes were enriched in metabolic processes, while downregulated genes were associated with the immune response. Serine protease inhibitor Kazal-type 2 (SPINK2) ranked first among all the upregulated genes and was regarded as a hub gene in the development of AML. The overexpression of SPINK2 was validated in 12 patients with AML from the Linyi Central Hospital and in data from the Oncomine and Gene Expression Profiling Interactive Analysis (GEPIA) databases. Furthermore, the UALCAN and GEPIA datasets demonstrated that patients with high SPINK2 levels had shorter survival times. In conclusion, the results from the present study revealed that the SPINK2 gene was upregulated in patients with AML and that elevated SPINK2 expression was associated with poor outcomes in these patients.

Long non-coding RNAs in Oral squamous cell carcinoma: biologic function, mechanisms and clinical implications

There is growing evidence that regions of the genome that cannot encode proteins play an important role in diseases. These regions are usually transcribed into long non-coding RNAs (lncRNAs). LncRNAs, little or no coding potential, are defined as capped transcripts longer than 200 nucleotides. New sequencing technologies have shown that a large number of aberrantly expressed lncRNAs are associated with multiple cancer types and indicated they have emerged as an important class of pervasive genes during the development and progression of cancer. However, the underlying mechanism in cancer is still unknown. Therefore, it is necessary to elucidate the lncRNA function. Notably, many lncRNAs dysregulation are associated with Oral squamous cell carcinoma (OSCC) and affect various aspects of cellular homeostasis, including proliferation, survival, migration or genomic stability. This review expounds the up- or down-regulation of lncRNAs in OSCC and the molecular mechanisms by which lncRNAs perform their function in the malignant cell. Finally, the potential of lncRNAs as non-invasive biomarkers for OSCC diagnosis are also described. LncRNAs hold promise as prospective novel therapeutic targets, but more research is needed to gain a better understanding of their biologic function.

lncRNA Spehd Regulates Hematopoietic Stem and Progenitor Cells and Is Required for Multilineage Differentiation

Long non-coding RNAs (lncRNAs) show patterns of tissue- and cell type-specific expression that are very similar to those of protein coding genes and consequently have the potential to control stem and progenitor cell fate decisions along a differentiation trajectory. To understand the roles that lncRNAs may play in hematopoiesis, we selected a subset of mouse lncRNAs with potentially relevant expression patterns and refined our candidate list using evidence of conserved expression in human blood lineages. For each candidate, we assessed its possible role in hematopoietic differentiation in vivo using competitive transplantation. Our studies identified two lncRNAs that were required for hematopoiesis. One of these, Spehd, showed defective multilineage differentiation, and its silencing yielded common myeloid progenitors that are deficient in their oxidative phosphorylation pathway. This effort not only suggests that lncRNAs can contribute to differentiation decisions during hematopoiesis but also provides a path toward the identification of functional lncRNAs in other differentiation hierarchies.

Hacking the Cancer Genome: Profiling Therapeutically Actionable Long Non-coding RNAs Using CRISPR-Cas9 Screening

Long non-coding RNAs (lncRNAs) represent a huge reservoir of potential cancer targets. Such "onco-lncRNAs" have resisted traditional RNAi methods, but CRISPR-Cas9 genome editing now promises functional screens at high throughput and low cost. The unique biology of lncRNAs demands screening strategies distinct from protein-coding genes. The first such screens have identified hundreds of onco-lncRNAs promoting cell proliferation and drug resistance. Ongoing developments will further improve screen performance and translational relevance. This Review aims to highlight the potential of CRISPR screening technology for discovering new onco-lncRNAs, and to guide molecular oncologists wishing to apply it to their cancer of interest.