A genome-wide long noncoding RNA CRISPRi screen identifies PRANCR as a novel regulator of epidermal homeostasis

lncRNA LINC00941 modulates MTA2/NuRD occupancy to suppress premature human epidermal differentiation

Numerous long non-coding RNAs (lncRNAs) were shown to have a functional impact on cellular processes such as human epidermal homeostasis. However, the mechanism of action for many lncRNAs remains unclear to date. Here, we report that lncRNA LINC00941 regulates keratinocyte differentiation on an epigenetic level through association with the NuRD complex, one of the major chromatin remodelers in cells. We find that LINC00941 interacts with NuRD-associated MTA2 and CHD4 in human primary keratinocytes. LINC00941 perturbation changes MTA2/NuRD occupancy at bivalent chromatin domains in close proximity to transcriptional regulator genes, including the EGR3 gene coding for a transcription factor regulating epidermal differentiation. Notably, LINC00941 depletion resulted in reduced NuRD occupancy at the EGR3 gene locus, increased EGR3 expression in human primary keratinocytes, and increased abundance of EGR3-regulated epidermal differentiation genes in cells and human organotypic epidermal tissues. Our results therefore indicate a role of LINC00941/NuRD in repressing EGR3 expression in non-differentiated keratinocytes, consequentially preventing premature differentiation of human epidermal tissues.

Non-coding RNAs as skin disease biomarkers, molecular signatures, and therapeutic targets

Non-coding RNAs (ncRNAs) are emerging as biomarkers, molecular signatures, and therapeutic tools and targets for diseases. In this review, we focus specifically on skin diseases to highlight how two classes of ncRNAs-microRNAs and long noncoding RNAs-are being used to diagnose medical conditions of unclear etiology, improve our ability to guide treatment response, and predict disease prognosis. Furthermore, we explore how ncRNAs are being used as both as drug targets and associated therapies have unique benefits, risks, and challenges to development, but offer a distinctive promise for improving patient care and outcomes.

Discovery platforms for RNA therapeutics

RNA therapeutics are emerging as a unique opportunity to drug currently "undruggable" molecules and diseases. While their advantages over conventional, small molecule drugs, their therapeutic implications and the tools for their effective in vivo delivery have been extensively reviewed, little attention has been so far paid to the technological platforms exploited for the discovery of RNA therapeutics. Here, we provide an overview of the existing platforms and ex vivo assays for RNA discovery, their advantages and disadvantages, as well as their main fields of application, with specific focus on RNA therapies that have reached either phase 3 or market approval.

CRISPR-Cas13d screens identify KILR, a breast cancer risk-associated lncRNA that regulates DNA replication and repair

BACKGROUND

Long noncoding RNAs (lncRNAs) have surpassed the number of protein-coding genes, yet the majority have no known function. We previously discovered 844 lncRNAs that were genetically linked to breast cancer through genome-wide association studies (GWAS). Here, we show that a subset of these lncRNAs alter breast cancer risk by modulating cell proliferation, and provide evidence that a reduced expression on one lncRNA increases breast cancer risk through aberrant DNA replication and repair.

METHODS

We performed pooled CRISPR-Cas13d-based knockdown screens in breast cells to identify which of the 844 breast cancer-associated lncRNAs alter cell proliferation. We selected one of the lncRNAs that increased cell proliferation, KILR, for follow-up functional studies. KILR pull-down followed by mass spectrometry was used to identify binding proteins. Knockdown and overexpression studies were performed to assess the mechanism by which KILR regulates proliferation.

RESULTS

We show that KILR functions as a tumor suppressor, safeguarding breast cells against uncontrolled proliferation. The half-life of KILR is significantly reduced by the risk haplotype, revealing an alternative mechanism by which variants alter cancer risk. Mechanistically, KILR sequesters RPA1, a subunit of the RPA complex required for DNA replication and repair. Reduced KILR expression promotes breast cancer cell proliferation by increasing the available pool of RPA1 and speed of DNA replication. Conversely, KILR overexpression promotes apoptosis in breast cancer cells, but not normal breast cells.

CONCLUSIONS

Our results confirm lncRNAs as mediators of breast cancer risk, emphasize the need to annotate noncoding transcripts in relevant cell types when investigating GWAS variants and provide a scalable platform for mapping phenotypes associated with lncRNAs.

Techniques for investigating lncRNA transcript functions in neurodevelopment

Long noncoding RNAs (lncRNAs) are sequences of 200 nucleotides or more that are transcribed from a large portion of the mammalian genome. While hypothesized to have a variety of biological roles, many lncRNAs remain largely functionally uncharacterized due to unique challenges associated with their investigation. For example, some lncRNAs overlap with other genomic loci, are expressed in a cell-type-specific manner, and/or are differentially processed at the post-transcriptional level. The mammalian CNS contains a vast diversity of lncRNAs, and lncRNAs are highly abundant in the mammalian brain. However, interrogating lncRNA function in models of the CNS, particularly in vivo, can be complex and challenging. Here we review the breadth of methods used to investigate lncRNAs in the CNS, their merits, and the understanding they can provide with respect to neurodevelopment and pathophysiology. We discuss remaining challenges in the field and provide recommendations to assay lncRNAs based on current methods.

dCas9 Tells Tales: Probing Gene Function and Transcription Regulation in Cancer

Clustered regularly interspaced short palindromic repeats (CRISPR)-based genome editing is evolving into an essential tool in the field of biological and medical research. Notably, the development of catalytically deactivated Cas9 (dCas9) enzyme has substantially broadened its traditional boundaries in gene editing or perturbation. The conjugation of dCas9 with various molecular effectors allows precise control over transcriptional processes, epigenetic modifications, visualization of chromosomal dynamics, and several other applications. This expanded repertoire of CRISPR-Cas9 applications has emerged as an invaluable molecular tool kit that empowers researchers to comprehensively interrogate and gain insights into health and diseases. This review delves into the advancements in Cas9 protein engineering, specifically on the generation of various dCas9 tools that have significantly enhanced the CRISPR-based technology capability and versatility. We subsequently discuss the multifaceted applications of dCas9, especially in interrogating the regulation and function of genes that involve in supporting cancer pathogenesis. In addition, we also delineate the designing and utilization of dCas9-based tools as well as highlighting its current constraints and transformative potentials in cancer research.

Molecular mechanism of lncRNAs in pathogenesis and diagnosis of auto-immune diseases, with a special focus on lncRNA-based therapeutic approaches

Autoimmune diseases are a diverse set of conditions defined by organ damage due to abnormal innate and acquired immune system responses. The pathophysiology of autoimmune disorders is exceedingly intricate and has yet to be fully understood. The study of long non-coding RNAs (lncRNAs), non-protein-coding RNAs with at least 200 nucleotides in length, has gained significant attention due to the completion of the human genome project and the advancement of high-throughput genomic approaches. Recent research has demonstrated how lncRNA alters disease development to different degrees. Although lncRNA research has made significant progress in cancer and generative disorders, autoimmune illnesses are a relatively new research area. Moreover, lncRNAs play crucial functions in differentiating various immune cells, and their potential relationships with autoimmune diseases have received growing attention. Because of the importance of Th17/Treg axis in auto-immune disease development, in this review, we discuss various molecular mechanisms by which lncRNAs regulate the differentiation of Th17/Treg cells. Also, we reviewed recent findings regarding the several approaches in the application of lncRNAs in the diagnosis and treatment of human autoimmune diseases, as well as current challenges in lncRNA-based therapeutic approaches to auto-immune diseases.

Long noncoding RNA study: Genome-wide approaches

Long noncoding RNAs (lncRNAs) have been confirmed to play a crucial role in various biological processes across several species. Though many efforts have been devoted to the expansion of the lncRNAs landscape, much about lncRNAs is still unknown due to their great complexity. The development of high-throughput technologies and the constantly improved bioinformatic methods have resulted in a rapid expansion of lncRNA research and relevant databases. In this review, we introduced genome-wide research of lncRNAs in three parts: (i) novel lncRNA identification by high-throughput sequencing and computational pipelines; (ii) functional characterization of lncRNAs by expression atlas profiling, genome-scale screening, and the research of cancer-related lncRNAs; (iii) mechanism research by large-scale experimental technologies and computational analysis. Besides, primary experimental methods and bioinformatic pipelines related to these three parts are summarized. This review aimed to provide a comprehensive and systemic overview of lncRNA genome-wide research strategies and indicate a genome-wide lncRNA research system.

Exposure of volunteers to microgravity by dry immersion bed over 21 days results in gene expression changes and adaptation of T cells

The next steps of deep space exploration are manned missions to Moon and Mars. For safe space missions for crew members, it is important to understand the impact of space flight on the immune system. We studied the effects of 21 days dry immersion (DI) exposure on the transcriptomes of T cells isolated from blood samples of eight healthy volunteers. Samples were collected 7 days before DI, at day 7, 14, and 21 during DI, and 7 days after DI. RNA sequencing of CD3+ T cells revealed transcriptional alterations across all time points, with most changes occurring 14 days after DI exposure. At day 21, T cells showed evidence of adaptation with a transcriptional profile resembling that of 7 days before DI. At 7 days after DI, T cells again changed their transcriptional profile. These data suggest that T cells adapt by rewiring their transcriptomes in response to simulated weightlessness and that remodeling cues persist when reexposed to normal gravity.

Long non-coding RNAs: definitions, functions, challenges and recommendations

Genes specifying long non-coding RNAs (lncRNAs) occupy a large fraction of the genomes of complex organisms. The term 'lncRNAs' encompasses RNA polymerase I (Pol I), Pol II and Pol III transcribed RNAs, and RNAs from processed introns. The various functions of lncRNAs and their many isoforms and interleaved relationships with other genes make lncRNA classification and annotation difficult. Most lncRNAs evolve more rapidly than protein-coding sequences, are cell type specific and regulate many aspects of cell differentiation and development and other physiological processes. Many lncRNAs associate with chromatin-modifying complexes, are transcribed from enhancers and nucleate phase separation of nuclear condensates and domains, indicating an intimate link between lncRNA expression and the spatial control of gene expression during development. lncRNAs also have important roles in the cytoplasm and beyond, including in the regulation of translation, metabolism and signalling. lncRNAs often have a modular structure and are rich in repeats, which are increasingly being shown to be relevant to their function. In this Consensus Statement, we address the definition and nomenclature of lncRNAs and their conservation, expression, phenotypic visibility, structure and functions. We also discuss research challenges and provide recommendations to advance the understanding of the roles of lncRNAs in development, cell biology and disease.

Human skin specific long noncoding RNA HOXC13-AS regulates epidermal differentiation by interfering with Golgi-ER retrograde transport

After a skin injury, keratinocytes switch from a state of homeostasis to one of regeneration leading to the reconstruction of the epidermal barrier. The regulatory mechanism of gene expression underpinning this key switch during human skin wound healing is enigmatic. Long noncoding RNAs (lncRNAs) constitute a new horizon in the understanding of the regulatory programs encoded in the mammalian genome. By comparing the transcriptome of an acute human wound and skin from the same donor as well as keratinocytes isolated from these paired tissue samples, we generated a list of lncRNAs showing changed expression in keratinocytes during wound repair. Our study focused on HOXC13-AS, a recently evolved human lncRNA specifically expressed in epidermal keratinocytes, and we found that its expression was temporally downregulated during wound healing. In line with its enrichment in suprabasal keratinocytes, HOXC13-AS was found to be increasingly expressed during keratinocyte differentiation, but its expression was reduced by EGFR signaling. After HOXC13-AS knockdown or overexpression in human primary keratinocytes undergoing differentiation induced by cell suspension or calcium treatment and in organotypic epidermis, we found that HOXC13-AS promoted keratinocyte differentiation. Moreover, RNA pull-down assays followed by mass spectrometry and RNA immunoprecipitation analysis revealed that mechanistically HOXC13-AS sequestered the coat complex subunit alpha (COPA) protein and interfered with Golgi-to-endoplasmic reticulum (ER) molecular transport, resulting in ER stress and enhanced keratinocyte differentiation. In summary, we identified HOXC13-AS as a crucial regulator of human epidermal differentiation.

RNA out of the mist

RNA has long been regarded primarily as the intermediate between genes and proteins. It was a surprise then to discover that eukaryotic genes are mosaics of mRNA sequences interrupted by large tracts of transcribed but untranslated sequences, and that multicellular organisms also express many long 'intergenic' and antisense noncoding RNAs (lncRNAs). The identification of small RNAs that regulate mRNA translation and half-life did not disturb the prevailing view that animals and plant genomes are full of evolutionary debris and that their development is mainly supervised by transcription factors. Gathering evidence to the contrary involved addressing the low conservation, expression, and genetic visibility of lncRNAs, demonstrating their cell-specific roles in cell and developmental biology, and their association with chromatin-modifying complexes and phase-separated domains. The emerging picture is that most lncRNAs are the products of genetic loci termed 'enhancers', which marshal generic effector proteins to their sites of action to control cell fate decisions during development.

A Novel CRISPR Interference Effector Enabling Functional Gene Characterization with Synthetic Guide RNAs

While CRISPR interference (CRISPRi) systems have been widely implemented in pooled lentiviral screening, there has been limited use with synthetic guide RNAs for the complex phenotypic readouts enabled by experiments in arrayed format. Here we describe a novel deactivated Cas9 fusion protein, dCas9-SALL1-SDS3, which produces greater target gene repression than first or second generation CRISPRi systems when used with chemically modified synthetic single guide RNAs (sgRNAs), while exhibiting high target specificity. We show that dCas9-SALL1-SDS3 interacts with key members of the histone deacetylase and Swi-independent three complexes, which are the endogenous functional effectors of SALL1 and SDS3. Synthetic sgRNAs can also be used with in vitro-transcribed dCas9-SALL1-SDS3 mRNA for short-term delivery into primary cells, including human induced pluripotent stem cells and primary T cells. Finally, we used dCas9-SALL1-SDS3 for functional gene characterization of DNA damage host factors, orthogonally to small interfering RNA, demonstrating the ability of the system to be used in arrayed-format screening.

Mechanistic Contributions of lncRNAs to Cellular Signaling Pathways Crucial to the Lifecycle of Human Papillomaviruses

Papillomaviruses are ubiquitous epitheliotropic viruses with double-stranded circular DNA genomes of approximately 8000 base pairs. The viral life cycle is somewhat unusual in that these viruses can establish persistent infections in the mitotically active basal epithelial cells that they initially infect. High-level viral genome replication ("genome amplification"), the expression of capsid proteins, and the formation of infectious progeny are restricted to terminally differentiated cells where genomes are synthesized at replication factories at sites of double-strand DNA breaks. To establish persistent infections, papillomaviruses need to retain the basal cell identity of the initially infected cells and restrain and delay their epithelial differentiation program. To enable high-level viral genome replication, papillomaviruses also need to hold the inherently growth-arrested terminally differentiated cells in a replication-competent state. To provide ample sites for viral genome synthesis, they target the DNA damage and repair machinery. Studies focusing on delineating cellular factors that are targeted by papillomaviruses may aid the development of antivirals. Whilst most of the current research efforts focus on protein targets, the majority of the human transcriptome consists of noncoding RNAs. This review focuses on one specific class of noncoding RNAs, long noncoding RNAs (lncRNAs), and summarizes work on lncRNAs that may regulate the cellular processes that are subverted by papillomavirus to enable persistent infections and progeny synthesis.

Multiplexed functional genomic assays to decipher the noncoding genome

Linkage disequilibrium and the incomplete regulatory annotation of the noncoding genome complicates the identification of functional noncoding genetic variants and their causal association with disease. Current computational methods for variant prioritization have limited predictive value, necessitating the application of highly parallelized experimental assays to efficiently identify functional noncoding variation. Here, we summarize two distinct approaches, massively parallel reporter assays and CRISPR-based pooled screens and describe their flexible implementation to characterize human noncoding genetic variation at unprecedented scale. Each approach provides unique advantages and limitations, highlighting the importance of multimodal methodological integration. These multiplexed assays of variant effects are undoubtedly poised to play a key role in the experimental characterization of noncoding genetic risk, informing our understanding of the underlying mechanisms of disease-associated loci and the development of more robust predictive classification algorithms.

Contribution of the Environment, Epigenetic Mechanisms and Non-Coding RNAs in Psoriasis

Despite the increasing research and clinical interest in the predisposition of psoriasis, a chronic inflammatory skin disease, the multitude of genetic and environmental factors involved in its pathogenesis remain unclear. This complexity is further exacerbated by the several cell types that are implicated in Psoriasis’s progression, including keratinocytes, melanocytes and various immune cell types. The observed interactions between the genetic substrate and the environment lead to epigenetic alterations that directly or indirectly affect gene expression. Changes in DNA methylation and histone modifications that alter DNA-binding site accessibility, as well as non-coding RNAs implicated in the post-transcriptional regulation, are mechanisms of gene transcriptional activity modification and therefore affect the pathways involved in the pathogenesis of Psoriasis. In this review, we summarize the research conducted on the environmental factors contributing to the disease onset, epigenetic modifications and non-coding RNAs exhibiting deregulation in Psoriasis, and we further categorize them based on the under-study cell types. We also assess the recent literature considering therapeutic applications targeting molecules that compromise the epigenome, as a way to suppress the inflammatory cutaneous cascade.

Recent advances of the biological and biomedical applications of CRISPR/Cas systems

The clustered, regularly interspaced, short palindromic repeats (CRISPR)-associated endonuclease (Cas) system, referred to as CRISPR/Cas system, has attracted significant interest in scientific community due to its great potential in translating into versatile therapeutic tools in biomedical field. For instance, a myriad of studies has demonstrated that the CRISPR/Cas system is capable of detecting various types of viruses, killing antibiotic-resistant bacteria, treating inherited genetic diseases, and providing new strategies for cancer therapy. Furthermore, CRISPR/Cas systems are also exploited as research tools such as genome engineering tool that allows researchers to interrogate the biological roles of unexplored genes or uncover novel functions of known genes. Additionally, the CRISPR/Cas system has been employed to edit the genome of a wide range of eukaryotic, prokaryotic organisms and experimental models, including but not limited to mammalian cells, mice, zebrafish, plants, yeast, and Escherichia coli. The present review mainly focuses on summarizing recent discoveries regarding the type II CRISPR/Cas9 and type VI CRISPR/Cas13a systems to give researchers a glimpse of their potential applications in the biological and biomedical field.

Fabricating a Novel Three-Dimensional Skin Model Using Silica Nonwoven Fabrics (SNF)

Silica nonwoven fabrics (SNF) prepared using electrospinning have high biocompatibility, thermal stability, and porosity that allows growing three-dimensional culture of cells. In this study, we used SNF to construct a three-dimensional artificial skin model consisting of epidermal and dermal layers with immortalized and primary human cell lines, creating a novel model that minimizes tissue shrinkage. As a result, SNF dermal/epidermal models have enhanced functions in the basement membrane, whereas Collagen dermal/epidermal models have advantages in keratinization and barrier functions. The SNF dermal/epidermal model with mechanical strength formed a basement membrane mimicking structure, suggesting the construction of a stable skin model. Next, we constructed three-dimensional skin models consisting of SNF and collagen. In the combination models, the expression of genes in the basement membrane was significantly increased compared with that in the Collagen dermal/epidermal model, and the gene for keratinization was increased compared with that in the SNF dermal/epidermal model. We believe that the combination model can be a biomimetic model that takes advantage of both SNF and collagen and can be applied to various basic research. Our new skin model is expected to be an alternative method for skin testing to improve the shrinkage of the collagen matrix gel.

Identification of a novel prognostic signature for HCC and analysis of costimulatory molecule-related lncRNA AC099850.3

Costimulatory molecules are involved in initiation of anti-tumor immune responses while long non‐coding RNAs (lncRNAs) regulate the development of various cancers. However, the roles of lncRNA in hepatocellular carcinoma (HCC) have not been fully established. In this study, we aimed at identifying lncRNAs-related costimulatory molecules in HCC and to construct a prognostic signature for predicting the clinical outcomes for HCC patients. Data were downloaded from The Cancer Genome Atlas database for bioinformatics analyses. Costimulatory molecules were obtained from published literature. The R software, SPSS, and GraphPad Prism were used for statistical analyses. A risk model that is based on five costimulatory molecule-related lncRNAs was constructed using lasso and Cox regression analyses. Multivariate regression analysis revealed that the risk score could predict the prognostic outcomes for HCC. Samples in high- and low-risk groups exhibited significant differences in gene set enrichment and immune infiltration levels. Through colony formation and CCK8 assays, we found that AC099850.3 was strongly associated with HCC cell proliferation. We identified and validated a novel costimulatory molecule-related survival model. In addition, AC099850.3 was found to be closely associated with clinical stages and proliferation of HCC cells, making it a potential target for HCC treatment.

Systematic lncRNA mapping to genome-wide co-essential modules uncovers cancer dependency on uncharacterized lncRNAs

Quantification of gene dependency across hundreds of cell lines using genome-scale CRISPR screens has revealed co-essential pathways/modules and critical functions of uncharacterized genes. In contrast to protein-coding genes, robust CRISPR-based loss-of-function screens are lacking for long noncoding RNAs (lncRNAs), which are key regulators of many cellular processes, leaving many essential lncRNAs unidentified and uninvestigated. Integrating copy number, epigenetic, and transcriptomic data of >800 cancer cell lines with CRISPR-derived co-essential pathways, our method recapitulates known essential lncRNAs and predicts proliferation/growth dependency of 289 poorly characterized lncRNAs. Analyzing lncRNA dependencies across 10 cancer types and their expression alteration by diverse growth inhibitors across cell types, we prioritize 30 high-confidence pan-cancer proliferation/growth-regulating lncRNAs. Further evaluating two previously uncharacterized top proliferation-suppressive lncRNAs (PSLR-1, PSLR-2) showed they are transcriptionally regulated by p53, induced by multiple cancer treatments, and significantly correlate to increased cancer patient survival. These lncRNAs modulate G2 cell cycle-regulating genes within the FOXM1 transcriptional network, inducing a G2 arrest and inhibiting proliferation and colony formation. Collectively, our results serve as a powerful resource for exploring lncRNA-mediated regulation of cellular fitness in cancer, circumventing current limitations in lncRNA research.

Development and Validation of Ferroptosis- and Immune-Related lncRNAs Signatures for Breast Infiltrating Duct and Lobular Carcinoma

Background

Heterogeneity of breast cancer (BRCA) is significantly correlated with its prognosis. Target therapy for ferroptosis and immunity is a new cancer treatment option discovered in recent years. In the present study, we aimed to identify ferroptosis- and immune-related long non-coding RNAs (lncRNAs) to accurately predict the prognosis and diagnosis of patients with breast infiltrating duct and lobular carcinoma by integrated analyses.

Methods

The corresponding data for the patients with breast infiltrating duct and lobular carcinoma by integrated analyses were obtained from The Cancer Genome Atlas (TCGA). Analyses of univariate and multivariate Cox regressions were used to identify the suitable candidate biomarkers.

Results

We found that seven ferroptosis- and immune-related differentially expressed lncRNAs (FI-DELs) (AC007686.3, AC078883.1, ADAMTS9-AS1, AL035661.1, CBR3-AS1, FTX, and TMEM105) were correlated with the overall survival of patients with breast infiltrating duct and lobular carcinoma. The areas under the receiver operating characteristic (AUCs) value of the prognosis model were all over 0.6 in training, validation, and entire groups. The sensitivity and specificity of the diagnosis model was 87.84% and 97.06%, respectively.

Conclusions

Through a series of bioinformatics analyses, we found that the seven FI-DELs could serve as prognostic and diagnostic biomarkers for patients with breast infiltrating duct and lobular carcinoma. However, whether these seven biomarkers could be really applied to the clinic requires further investigations.

Identification and validation of a twelve immune infiltration-related lncRNA prognostic signature for bladder cancer

The prognosis of bladder cancer patients is strongly related to both the immune-infiltrating cells and the expression of lncRNAs. In this study, we analyzed the infiltration of immune cells in 403 bladder cancer samples obtained from TCGA by applying the ssGSEA to these samples, then dividing them into high/low immune cell infiltration groups. Based on these groupings, we found 404 differentially expressed immune infiltration-related lncRNAs, which were successively analyzed by univariate Cox regression, then Least Absolute Shrinkage and Selection Operator (LASSO), and finally stepwise multiple Cox regression. Then 12 differentially expressed immune infiltration-related lncRNAs were identified and used to construct a prognostic signature for bladder cancer. Subsequently, Kaplan-Meier analysis, univariate Cox regression, multivariate Cox regression, and multivariate time-dependent ROC analyses (for 1, 3, 5 years) all revealed that this signature performed well in predicting overall survival and served as an independent prognostic factor for patients with bladder cancer. Finally, both TIMER and CIBESORT showed that this 12-lncRNA prognostic signature for bladder cancer was associated with the infiltration of immune cell subtypes. Besides, nomogram considered risk score and clinical characteristics was assembled and showed great performance. More importantly, we found our signature could well distinguish the drug response of patients with bladder cancer. High risk patients showed a better response to cisplatin, doxorubicin, and anti- CTLA4 immunotherapy, low risk patients showed a better response to methotrexate and anti-PD1 immunotherapy compared with each other.

Gene editing and its applications in biomedicine

The steady progress in genome editing, especially genome editing based on the use of clustered regularly interspaced short palindromic repeats (CRISPR) and programmable nucleases to make precise modifications to genetic material, has provided enormous opportunities to advance biomedical research and promote human health. The application of these technologies in basic biomedical research has yielded significant advances in identifying and studying key molecular targets relevant to human diseases and their treatment. The clinical translation of genome editing techniques offers unprecedented biomedical engineering capabilities in the diagnosis, prevention, and treatment of disease or disability. Here, we provide a general summary of emerging biomedical applications of genome editing, including open challenges. We also summarize the tools of genome editing and the insights derived from their applications, hoping to accelerate new discoveries and therapies in biomedicine.

Identification of an Autophagy-Related lncRNA Prognostic Signature and Related Tumor Immunity Research in Lung Adenocarcinoma

Autophagy is closely associated with the tumor immune microenvironment (TIME) and prognosis of patients with lung adenocarcinoma (LUAD). In the present study, we established a signature on the basis of long noncoding RNAs (lncRNAs) related to autophagy (ARlncRNAs) to investigate the TIME and survival of patients with LUAD. We selected ARlncRNAs associated with prognosis to construct a model and divided each sample into different groups on the basis of risk score. The ARlncRNA signature could be recognized as an independent prognostic factor for patients with LUAD, and patients in the low-risk group had a greater survival advantage. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analysis suggested that several immune functions and pathways were enriched in different groups. A high-risk score correlated significantly negatively with high abundance of immune cells and stromal cells around the tumor and high tumor mutational burden. Low-risk patients had a higher PD-1, CTLA-4, and HAVCR2 expression and had a better efficacy of immune checkpoint inhibitors, including PD-1/CTLA-4 inhibitor. A reliable signature on the basis of ARlncRNAs was constructed to explore the TIME and prognosis of patients with LUAD, which could provide valuable information for individualized LUAD treatment.

Transcriptome sequencing analysis for the identification of stable lncRNAs associated with bovine Staphylococcus aureus mastitis

Background

Staphylococcus aureus (S. aureus) mastitis is one of the most difficult diseases to treat in lactating dairy cows worldwide. S. aureus with different lineages leads to different host immune responses. Long non-coding RNAs (lncRNAs) are reported to be widely involved in the progress of inflammation. However, no research has identified stable lncRNAs among different S. aureus strain infections. In addition, folic acid (FA) can effectively reduce inflammation, and whether the inflammatory response caused by S. aureus can be reduced by FA remains to be explored.

Methods

lncRNA transcripts were identified from Holstein mammary gland tissues infected with different concentrations of S. aureus (in vivo) and mammary alveolar cells (Mac-T cells, in vitro) challenged with different S. aureus strains. Differentially expressed (DE) lncRNAs were evaluated, and stable DE lncRNAs were identified in vivo and in vitro. On the basis of the gene sequence conservation and function conservation across species, key lncRNAs with the function of potentially immune regulation were retained for further analysis. The function of FA on inflammation induced by S. aureus challenge was also investigated. Then, the association analysis between these keys lncRNA transcripts and hematological parameters (HPs) was carried out. Lastly, the knockdown and overexpression of the important lncRNA were performed to validate the gene function on the regulation of cell immune response.

Results

Linear regression analysis showed a significant correlation between the expression levels of lncRNA shared by mammary tissue and Mac-T cells (P < 0.001, R² = 0.3517). lncRNAs PRANCR and TNK2–AS1 could be regarded as stable markers associated with bovine S. aureus mastitis. Several HPs could be influenced by SNPs around lncRNAs PRANCR and TNK2–AS1. The results of gene function validation showed PRANCR regulates the mRNA expression of SELPLG and ITGB2 within the S. aureus infection pathway and the Mac-T cells apoptosis. In addition, FA regulated the expression change of DE lncRNA involved in toxin metabolism and inflammation to fight against S. aureus infection.

Conclusions

The remarkable association between SNPs around these two lncRNAs and partial HP indicates the potentially important role of PRANCR and TNK2–AS1 in immune regulation. Stable DE lncRNAs PRANCR and TNK2–AS1 can be regarded as potential targets for the prevention of bovine S. aureus mastitis. FA supplementation can reduce the negative effect of S. aureus challenge by regulating the expression of lncRNAs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-021-00639-2.

An Immune-Related lncRNA Signature to Predict the Biochemical Recurrence and Immune Landscape in Prostate Cancer

Purpose

This study aims to construct an immune-related signature to provide comprehensive insights into the immune landscape of prostate cancer, which can predict biochemical recurrence (BCR) and clinical treatment.

Methods

Based on The Cancer Genome Atlas (TCGA) dataset, a signature constructed by DEirlncRNAs pairs was determined. The receiver operating characteristic curve analysis, Kaplan-Meier analysis, nomogram, and decision curve analysis were used to analyze it. Then, immunophenoscore (IPS), immune cell infiltration, tumor mutation burden (TMB), and immune function were investigated. Finally, we evaluated the role of the signature in medical treatment.

Results

A signature constructed by 10 valid DEirlncRNAs pairs was identified in the training set and validated well in the testing and entire set. The signature was a reliable and independent prognostic indicator to predict the BCR of prostate cancer, which was better than the clinicopathological characteristics. After dividing the patients into low- and high-risk groups by median value, we found that the high-risk group had shorter BCR-free time and higher TMB levels. Furthermore, the high-risk group was negatively associated with plasma B cells and CD+8 T cells. IPS and immune functions, such as immune checkpoints and human leukocyte antigen, were significantly different between the two groups. Low-risk group was more sensitive to endocrine therapy and immunotherapy, while high-risk group was more inclined to targeted drugs. Both groups had their own sensitive chemotherapy.

Conclusion

We established a novel signature to predict BCR and validated its role in the immune landscape of prostate cancer, which could help patients receive personalized medical treatment.

Interrogating lncRNA functions via CRISPR/Cas systems

Long noncoding RNAs (lncRNAs) are an increasing focus of investigation due to their implications in diverse biological processes and disease. Nevertheless, the majority of lncRNAs are low in abundance and poorly conserved, posing challenges to functional studies. The CRISPR/Cas system, an innovative technology that has emerged over the last decade, can be utilized to further understand lncRNA function. The system targets specific DNA and/or RNA sequences via a guide RNA (gRNA) and Cas nuclease complex. We and others have utilized this technology in various applications such as lncRNA knockout, knockdown, overexpression, and imaging. In this review, we summarize how the CRISPR/Cas technology provides new tools to investigate the roles and therapeutic implications of lncRNAs.

Molecular characterization of metabolic subtypes of gastric cancer based on metabolism-related lncRNA

Increasing evidence has demonstrated that lncRNAs are critical regulators in diverse biological processes, but the function of lncRNA in metabolic regulation remains largely unexplored. In this study, we evaluated the association between lncRNA and metabolic pathways and identified metabolism-related lncRNAs. Gastric cancer can be mainly subdivided into 2 clusters based on these metabolism-related lncRNA regulators. Comparative analysis shows that these subtypes are found to be highly consistent with previously identified subtypes based on other omics data. Functional enrichment analysis shows that they are enriched in distinct biological processes. Mutation analysis shows that ABCA13 is a protective factor in subtype C1 but a risk factor in C2. Analysis of chemotherapeutic and immunotherapeutic sensitivity shows that these subtypes tend to display distinct sensitivity to the same chemical drugs. In conclusion, these findings demonstrated the significance of lncRNA in metabolic regulation. These metabolism-related lncRNA regulators can improve our understanding of the underlying mechanism of lncRNAs and advance the research of immunotherapies in the clinical management of gastric cancer.

Construction of Prognostic Risk Model of 5-Methylcytosine-Related Long Non-Coding RNAs and Evaluation of the Characteristics of Tumor-Infiltrating Immune Cells in Breast Cancer

Purpose: The role of 5-methylcytosine-related long non-coding RNAs (m5C-lncRNAs) in breast cancer (BC) remains unclear. Here, we aimed to investigate the prognostic value, gene expression characteristics, and correlation between m5C-lncRNA risk model and tumor immune cell infiltration in BC. Methods: The expression matrix of m5C-lncRNAs in BC was obtained from The Cancer Genome Atlas database, and the lncRNAs were analyzed using differential expression analysis as well as univariate and multivariate Cox regression analysis to eventually obtain BC-specific m5C-lncRNAs. A risk model was developed based on three lncRNAs using multivariate Cox regression and the prognostic value, accuracy, as well as reliability were verified. Gene set enrichment analysis (GSEA) was used to analyze the Kyoto Encyclopedia of Genes and Genomes signaling pathway enrichment of the risk model. CIBERSORT algorithm and correlation analysis were used to explore the characteristics of the BC tumor-infiltrating immune cells. Finally, reverse transcription-quantitative polymerase chain reaction was performed to detect the expression level of three lncRNA in clinical samples. Results: A total of 334 differential m5C-lncRNAs were identified, and three BC-specific m5C-lncRNAs were selected, namely AP005131.2, AL121832.2, and LINC01152. Based on these three lncRNAs, a highly reliable and specific risk model was constructed, which was proven to be closely related to the prognosis of patients with BC. Therefore, a nomogram based on the risk score was built to assist clinical decisions. GSEA revealed that the risk model was significantly enriched in metabolism-related pathways and was associated with tumor immune cell infiltration based on the analysis with the CIBERSORT algorithm. Conclusion: The efficient risk model based on m5C-lncRNAs associated with cancer metabolism and tumor immune cell infiltration could predict the survival prognosis of patients, and AP005131.2, AL121832.2, and LINC01152 could be novel biomarkers and therapeutic targets for BC.

Overexpression of the lncRNA AC012213.3 Promotes Proliferation, Migration and Invasion of Breast Cancer via RAD54B/PI3K/AKT Axis and is Associated with Worse Patient Prognosis

Background

Long noncoding RNA (LncRNA) has been shown to mediate the development of human malignancies. However, data on its role in breast cancer remains scant. We aimed to evaluate the prognostic potential of lncRNAs in breast cancer.

Methods

We downloaded data on breast cancer patients from The Cancer Genome Atlas (TCGA) database. Tissues were obtained from The Fifth People's Hospital of Chengdu. We then used the DESeq2 package to profile the expression of the lncRNAs between the patients and normal samples. Besides, we performed prognosis and survival analysis using survival tools in R package. We then assayed the role of the differentially expressed lncRNAs, AC012213.3 (ENSG00000266289), in cancer cell lines. Quantitative real-time PCR and Western blot analysis were performed to evaluate the expression of the gene in the cell lines and then assessed its role in the progression of breast cancer using cell proliferation (CCK8 and colony formation assays), migration, invasion (transwell and wound-healing assays) and apoptotic (flow cytometry) assays.

Results

Our data showed high expression of lncRNA AC012213.3 in breast cancer tissues and cell lines. The high expression of the AC012213.3 was associated with the worse prognosis and clinical features. Besides, in vitro assays demonstrated that downregulation of AC012213.3 suppresses the proliferation and invasion of breast cancer cells. Further analysis showed that RAD54B is a downstream AC012213.3 target gene and was upregulated in breast cancer. Interestingly, RAD54B expression was associated with shorter survival in breast cancer. In addition, AC012213.3 was shown to facilitate breast cancer progression through the RAD54B/PI3K/AKT axis.

Conclusion

Taken together, our data demonstrated that lncRNA AC012213.3 is upregulated in breast cancer and could enhance breast cancer progression through RAD54B/PI3K/AKT axis.

The Role of Epigenetic Factors in Psoriasis

Psoriasis is a chronic, systemic, immune-mediated disease with an incidence of approximately 2%. The pathogenesis of the disease is complex and not yet fully understood. Genetic factors play a significant role in the pathogenesis of the disease. In predisposed individuals, multiple trigger factors may contribute to disease onset and exacerbations of symptoms. Environmental factors (stress, infections, certain medications, nicotinism, alcohol, obesity) play a significant role in the pathogenesis of psoriasis. In addition, epigenetic mechanisms are considered result in modulation of individual gene expression and an increased likelihood of the disease. Studies highlight the significant role of epigenetic factors in the etiology and pathogenesis of psoriasis. Epigenetic mechanisms in psoriasis include DNA methylation, histone modifications and non-coding RNAs. Epigenetic mechanisms induce gene expression changes under the influence of chemical modifications of DNA and histones, which alter chromatin structure and activate transcription factors of selected genes, thus leading to translation of new mRNA without affecting the DNA sequence. Epigenetic factors can regulate gene expression at the transcriptional (via histone modification, DNA methylation) and posttranscriptional levels (via microRNAs and long non-coding RNAs). This study aims to present and discuss the different epigenetic mechanisms in psoriasis based on a review of the available literature.

Epigenetic Regulation of the Vascular Endothelium by Angiogenic LncRNAs

The functional properties of the vascular endothelium are diverse and heterogeneous between vascular beds. This is especially evident when new blood vessels develop from a pre-existing closed cardiovascular system, a process termed angiogenesis. Endothelial cells are key drivers of angiogenesis as they undergo a highly choreographed cascade of events that has both exogenous (e.g., hypoxia and VEGF) and endogenous regulatory inputs. Not surprisingly, angiogenesis is critical in health and disease. Diverse therapeutics target proteins involved in coordinating angiogenesis with varying degrees of efficacy. It is of great interest that recent work on non-coding RNAs, especially long non-coding RNAs (lncRNAs), indicates that they are also important regulators of the gene expression paradigms that underpin this cellular cascade. The protean effects of lncRNAs are dependent, in part, on their subcellular localization. For instance, lncRNAs enriched in the nucleus can act as epigenetic modifiers of gene expression in the vascular endothelium. Of great interest to genetic disease, they are undergoing rapid evolution and show extensive inter- and intra-species heterogeneity. In this review, we describe endothelial-enriched lncRNAs that have robust effects in angiogenesis.

Construction of an immune-related lncRNA signature as a novel prognosis biomarker for LUAD

The tumor immune microenvironment of lung cancer is associated with prognosis and immunotherapy efficacy. Long noncoding RNAs are identified as prognostic biomarkers associated with immune functions. We constructed a signature comprising differentially expressed immune-related lncRNAs to predict the prognosis of patients with lung adenocarcinoma. We established the immune-related lncRNA signature by pairing immune-related lncRNAs regardless of expression level and lung adenocarcinoma patients were divided into high- and low-risk groups. The prognosis of patients in the two groups was significantly different; The immune-related lncRNA signature could serve as an independent lung adenocarcinoma prognostic indicator. The signature correlated negatively with B cell, CD4+ T cell, M2 macrophage, neutrophil, and monocyte immune infiltration. Patients with low risk scores had a higher abundance of immune cells and stromal cells around the tumor. Gene set enrichment analysis showed that samples from low-risk group were more active in the IgA production in intestinal immune network and the T and B cell receptor signaling pathway. High-risk groups had significant involvement of the cell cycle, DNA replication, adherens junction, actin cytoskeleton regulation, pathways in cancer, and TGF-β signaling pathways. High risk scores correlated significantly negatively with high CTLA-4 and HAVCR2 expression and higher median inhibitory concentration of common anti-tumor chemotherapeutics (e.g., cisplatin, paclitaxel, gemcitabine) and targeted therapy (e.g., erlotinib and gefitinib). We identified a reliable immune-related lncRNA lung adenocarcinoma prognosis model, and the immune-related lncRNA signature showed promising clinical prediction value.

Long non-coding RNAs in diabetic wound healing: Current research and clinical relevance

Diabetic wounds are a protracted complication of diabetes mainly characterised by chronic inflammation, obstruction of epithelialization, damaged blood vessels and collagen production (maturation), as well as neuropathy. As a non‐coding RNA (ncRNA) that lack coding potential, long non‐coding RNAs (lncRNAs) have recently been reported to play a salient role in diabetic wound healing. Here, this review summarises the roles of lncRNAs in the pathology and treatments of diabetic wounds, providing references for its potential clinical diagnostic criteria or therapeutic targets in the future.

Functional examination of lncRNAs in allotetraploid Gossypium hirsutum

BACKGROUND

An evolutionary model using diploid and allotetraploid cotton species identified 80 % of non-coding transcripts in allotetraploid cotton as being uniquely activated in comparison with its diploid ancestors. The function of the lncRNAs activated in allotetraploid cotton remain largely unknown.

RESULTS

We employed transcriptome analysis to examine the relationship between the lncRNAs and mRNAs of protein coding genes (PCGs) in cotton leaf tissue under abiotic stresses. LncRNA expression was preferentially associated with that of the flanking PCGs. Selected highly-expressed lncRNA candidates (n = 111) were subjected to a functional screening pilot test in which virus-induced gene silencing was integrated with abiotic stress treatment. From this low-throughput screen, we obtained candidate lncRNAs relating to plant height and tolerance to drought and other abiotic stresses.

CONCLUSIONS

Low-throughput screen is an effective method to find functional lncRNA for further study. LncRNAs were more active in abiotic stresses than PCG expression, especially temperature stress. LncRNA XLOC107738 may take a cis-regulatory role in response to environmental stimuli. The degree to which lncRNAs are constitutively expressed may impact expression patterns and functions on the individual gene level rather than in genome-wide aggregate.

Functional annotation of lncRNA in high-throughput screening

Recent efforts on the characterization of long non-coding RNAs (lncRNAs) revealed their functional roles in modulating diverse cellular processes. These include pluripotency maintenance, lineage commitment, carcinogenesis, and pathogenesis of various diseases. By interacting with DNA, RNA and protein, lncRNAs mediate multifaceted mechanisms to regulate transcription, RNA processing, RNA interference and translation. Of more than 173000 discovered lncRNAs, the majority remain functionally unknown. The cell type-specific expression and localization of the lncRNA also suggest potential distinct functions of lncRNAs across different cell types. This highlights the niche of identifying functional lncRNAs in different biological processes and diseases through high-throughput (HTP) screening. This review summarizes the current work performed and perspectives on HTP screening of functional lncRNAs where different technologies, platforms, cellular responses and the downstream analyses are discussed. We hope to provide a better picture in applying different technologies to facilitate functional annotation of lncRNA efficiently.

Integrated analysis of immune-related long noncoding RNAs as diagnostic biomarkers in psoriasis

Background

Psoriasis is a chronic immune-mediated inflammatory dermatosis. Long noncoding RNAs (lncRNAs) play an important role in immune-related diseases. This study aimed to identify potential immune-related lncRNA biomarkers for psoriasis.

Methods

We screened differentially expressed immune-related lncRNAs biomarkers using GSE13355 (skin biopsy samples of 180 cases) from Gene Expression Omnibus (GEO). Moreover, Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and Gene Set Enrichment Analysis (GSEA) were performed to explore biological mechanisms in psoriasis. In addition, we performed LASSO logistic regression to identify potential diagnostic lncRNAs and further verify the diagnostic value and relationship with drug response using two validation sets: GSE30999 (skin biopsy samples of 170 cases) and GSE106992 (skin biopsy samples of 192 cases). Furthermore, we estimated the degree of infiltrated immune cells and investigated the correlation between infiltrated immune cells and diagnostic lncRNA biomarkers.

Results

A total of 394 differentially expressed genes (DEGs) were extracted from gene expression profile. GO and KEGG analysis of target genes found that immune-related lncRNAs were primarily associated with epidermis development, skin development, collagen-containing extracellular matrix, and glycosaminoglycan binding and mainly enriched in cytokine-cytokine receptor interaction and influenza A and chemokine signaling pathway. We found that LINC01137, LINC01215, MAPKAPK5-AS1, TPT1-AS1, CARMN, CCDC18-AS1, EPB41L4A-AS, and LINC01214 exhibited well diagnostic efficacy. The ROC and ROC CI were 0.944 (0.907–0.982), 0.953 (0.919–0.987), 0.822 (0.758–0.887), 0.854 (0.797–0.911), 0.957(0.929–0.985), 0.894 (0.846–0.942), and 0.964 (0.937–0.991) for LINC01137, LINC01215, MAPKAPK5-AS1, TPT1-AS1,CARMN, CCDC18-AS1, EPB41L4A-AS1, and LINC01214. LINC01137, LINC01215, and LINC01214 were correlated with drug response. LINC01137, CCDC18-AS1, and CARMN were positively correlated with activated memory CD4 T cell, activated myeloid dendritic cell (DC), neutrophils, macrophage M1, and T follicular helper (Tfh) cells, while negatively correlated with T regulatory cell (Treg). LINC01215, MAPKAPK5-AS1, TPT1-AS1, EPB41L4A-AS, and LINC01214 were negatively correlated with activated memory CD4 T cell, activated myeloid DC, neutrophils, macrophage M1, and Tfh, while positively correlated with Treg.

Conclusions

These findings indicated that these immune-related lncRNAs may be used as potential diagnostic and predictive biomarkers for psoriasis.

N6 -methyladenosine modification of lncRNA Pvt1 governs epidermal stemness

Dynamic chemical modifications of RNA represent novel and fundamental mechanisms that regulate stemness and tissue homeostasis. Rejuvenation and wound repair of mammalian skin are sustained by epidermal progenitor cells, which are localized within the basal layer of the skin epidermis. N⁶ -methyladenosine (m⁶ A) is one of the most abundant modifications found in eukaryotic mRNA and lncRNA (long noncoding RNA). In this report, we survey changes of m⁶ A RNA methylomes upon epidermal differentiation and identify Pvt1, a lncRNA whose m⁶ A modification is critically involved in sustaining stemness of epidermal progenitor cells. With genome-editing and a mouse genetics approach, we show that ablation of m⁶ A methyltransferase or Pvt1 impairs the self-renewal and wound healing capability of skin. Mechanistically, methylation of Pvt1 transcripts enhances its interaction with MYC and stabilizes the MYC protein in epidermal progenitor cells. Our study presents a global view of epitranscriptomic dynamics that occur during epidermal differentiation and identifies the m⁶ A modification of Pvt1 as a key signaling event involved in skin tissue homeostasis and wound repair.

Identification of a long non-coding RNA regulator of liver carcinoma cell survival

Genomic studies have significantly improved our understanding of hepatocellular carcinoma (HCC) biology and have led to the discovery of multiple protein-coding genes driving hepatocarcinogenesis. In addition, these studies have identified thousands of new non-coding transcripts deregulated in HCC. We hypothesize that some of these transcripts may be involved in disease progression. Long non-coding RNAs are a large class of non-coding transcripts which participate in the regulation of virtually all cellular functions. However, a majority of lncRNAs remain dramatically understudied. Here, we applied a pooled shRNA-based screen to identify lncRNAs essential for HCC cell survival. We validated our screening results using RNAi, CRISPRi, and antisense oligonucleotides. We found a lncRNA, termed ASTILCS, that is critical for HCC cell growth and is overexpressed in tumors from HCC patients. We demonstrated that HCC cell death upon ASTILCS knockdown is associated with apoptosis induction and downregulation of a neighboring gene, protein tyrosine kinase 2 (PTK2), a crucial protein for HCC cell survival. Taken together, our study describes a new, non-coding RNA regulator of HCC.

An update on the role of long non-coding RNAs in psoriasis

Increasing evidence suggests that long non-coding RNAs (lncRNAs) are of vital importance for various biological processes, and dysregulation of lncRNAs is frequently associated with various diseases such as psoriasis. LncRNAs modulate gene expression at the transcriptional, post-transcriptional, and translational levels; however, the specific regulatory mechanisms of lncRNAs in psoriasis remain largely unexplored. This review provides an overview of recent studies investigating mechanisms and functions of lncRNAs in psoriasis, especially focusing on the role of lncRNAs in keratinocytes, T cells, and dendritic cells.

Molecular characterization of breast cancer: a potential novel immune-related lncRNAs signature

Background

Accumulating evidence has demonstrated that immune-related lncRNAs (IRLs) are commonly aberrantly expressed in breast cancer (BC). Thus, we aimed to establish an IRL-based tool to improve prognosis prediction in BC patients.

Methods

We obtained IRL expression profiles in large BC cohorts (N = 911) from The Cancer Genome Atlas (TCGA) database. Then, in light of the correlation between each IRL and recurrence-free survival (RFS), we screened prognostic IRL signatures to construct a novel RFS nomogram via a Cox regression model. Subsequently, the performance of the IRL-based model was evaluated through discrimination, calibration ability, risk stratification ability and decision curve analysis (DCA).

Results

A total of 52 IRLs were obtained from TCGA. Based on multivariate Cox regression analyses, four IRLs (A1BG-AS1, AC004477.3, AC004585.1 and AC004854.2) and two risk parameters (tumor subtype and TNM stage) were utilized as independent indicators to develop a novel prognostic model. In terms of predictive accuracy, the IRL-based model was distinctly superior to the TNM staging system (AUC: 0.728 VS 0.673, P = 0.010). DCA indicated that our nomogram had favorable clinical practicability. In addition, risk stratification analysis showed that the IRL-based tool efficiently divided BC patients into high- and low-risk groups (P < 0.001).

Conclusions

A novel IRL-based model was constructed to predict the risk of 5-year RFS in BC. Our model can improve the predictive power of the TNM staging system and identify high-risk patients with tumor recurrence to implement more appropriate treatment strategies.

Research Techniques Made Simple: CRISPR Genetic Screens

CRISPR and Cas proteins, often referred to as CRISPR/Cas, are the components of a bacterial genome editing system that can be used to perturb genes in cells and tissues. A classic application is to use CRISPR/Cas to generate genetic loss-of-function. When performed at large scale and combined with deep sequencing techniques, CRISPR-based perturbations can be performed in a high throughput setting to screen many candidate genomic elements for their roles in a phenotype of interest. Here, we discuss major considerations in the design, execution, and analysis of CRISPR screens. We focus on CRISPR knockout screens but also review adaptations to the CRISPR/Cas system that highlight the versatility of the system to make other types of experimental genetic changes as well. We also discuss examples of CRISPR genetic screens in investigative dermatology and how they may be used to answer key scientific questions in the field.

Long non-coding RNAs in cutaneous biology and keratinocyte carcinomas

Long non-coding RNAs (lncRNAs) are a largely uncharacterized group of non-coding RNAs with diverse regulatory roles in various biological processes. Recent observations have elucidated the functional roles of lncRNAs in cutaneous biology, e.g. in proliferation and differentiation of epidermal keratinocytes and in cutaneous wound repair. Furthermore, the role of lncRNAs in keratinocyte-derived skin cancers is emerging, especially in cutaneous squamous cell carcinoma (cSCC), which presents a significant burden to health care services worldwide and causes high mortality as metastatic disease. Elucidation of the functions of keratinocyte-specific lncRNAs will improve understanding of the molecular pathogenesis of epidermal disorders and skin cancers and can be exploited in development of new diagnostic and therapeutic applications for keratinocyte carcinomas. In this review, we summarize the current evidence of functionally important lncRNAs in cutaneous biology and in keratinocyte carcinomas.

The Activity of KIF14, Mieap, and EZR in a New Type of the Invasive Component, Torpedo-Like Structures, Predetermines the Metastatic Potential of Breast Cancer

Intratumor morphological heterogeneity reflects patterns of invasive growth and is an indicator of the metastatic potential of breast cancer. In this study, we used this heterogeneity to identify molecules associated with breast cancer invasion and metastasis. The gene expression microarray data were used to identify genes differentially expressed between solid, trabecular, and other morphological arrangements of tumor cells. Immunohistochemistry was applied to evaluate the association of the selected proteins with metastasis. RNA-sequencing was performed to analyze the molecular makeup of metastatic tumor cells. High frequency of metastases and decreased metastasis-free survival were detected in patients either with positive expression of KIF14 or Mieap or negative expression of EZR at the tips of the torpedo-like structures in breast cancers. KIF14- and Mieap-positive and EZR-negative cells were mainly detected in the torpedo-like structures of the same breast tumors; however, their transcriptomic features differed. KIF14-positive cells showed a significant upregulation of genes involved in ether lipid metabolism. Mieap-positive cells were enriched in genes involved in mitophagy. EZR-negative cells displayed upregulated genes associated with phagocytosis and the chemokine-mediated signaling pathway. In conclusion, the positive expression of KIF14 and Mieap and negative expression of EZR at the tips of the torpedo-like structures are associated with breast cancer metastasis.

Identification of lncRNA-associated ceRNA network in high-grade serous ovarian cancer metastasis

Aim: To uncover a novel lncRNA-miRNA-mRNA network associated with high-grade serous ovarian cancer metastasis. Material & methods: The candidate differentially expressed lncRNAs were obtained from RNA-sequencing data and determined by functional experiments. The downstream miRNAs and mRNAs were identified by bioinformatic prediction and subjected to functional enrichment analysis. Results: The expression levels of lncRNA ENTPD1-AS1/PRANCR/NR2F2-AS1 were reduced in omental metastatic tissues. Similar differential expression patterns of these lncRNAs were also found in lnCAR database and we verified their tumor suppressive roles by performing functional experiments. Furthermore, we predicted miRNAs and mRNAs via bioinformatic tools and validated their alteration in expression levels in presence of lncRNA interference. Conclusion: We proposed a potential ceRNA regulatory mechanism in high-grade serous ovarian cancer omental metastasis.

TINCR is not a non-coding RNA but encodes a protein component of cornified epidermal keratinocytes

Long non-coding RNAs have been implicated in the regulation of a plethora of biological processes, yet it has been challenging to verify that they are truly not coding for proteins. Terminal differentiation-induced non-coding RNA (TINCR) is a 3.7-kilobase mRNA that is highly abundant in epidermal keratinocytes prior to cornification. Here, we report the presence of an evolutionarily conserved open reading frame in TINCR and the identification of peptides derived from this open reading frame in the proteome of human stratum corneum. Our results demonstrate that TINCR is a protein-coding RNA and suggest that the TINCR-encoded protein is involved in keratinocyte cornification.

Identification and validation of immune-related lncRNA prognostic signature for breast cancer

The prognosis of patients with breast cancer is closely related to both the infiltration of immune cells and the expression of lncRNAs. In this study, we evaluated the infiltration of immune cells in 1109 breast cancer samples obtained from TCGA by applying the ssGSEA to the transcriptome of these samples, thereby generating high immune cell infiltration group and low immune cell infiltration group. On the basis of these groupings, we found 696 differentially expressed lncRNAs which were sequentially subjected to univariate Cox regression and stepwise multiple Cox regression analysis. 11 lncRNAs were identified as prognostic signature for breast cancer. Kaplan-Meier analysis, univariate Cox regression, multivariate Cox regression, and ROC analyses further revealed that this 11-lncRNA signature was a novel and important prognostic factor independent of multiple clinicopathological parameters. The TIMER database showed that this 11-lncRNA prognostic signature for breast cancer was associated with the infiltration of immune cell subtypes.