Therapeutic RNA aptamers in clinical trials

Aptamer-assisted phage display: enhancing checkpoint inhibition with a peptide and an aptamer targeting distinct sites on a single PD-L1 protein

Utilizing a novel approach known as aptamer-assisted phage display (APD), we identified an anti-PD-L1 peptide, NV Pep, capable of simultaneous binding to PD-L1 alongside the DNA aptamer MJ5C. Combined inhibition using NV Pep and MJ5C demonstrated significant enhancement compared to individual ligands against the PD-1/PD-L1 interaction.

A functional RNA-origami as direct thrombin inhibitor with fast-acting and specific single-molecule reversal agents in vivo model

Injectable anticoagulants are widely used in medical procedures to prevent unwanted blood clotting. However, many lack safe, effective reversal agents. Here, we present new data on a previously described RNA origami-based, direct thrombin inhibitor (HEX01). We describe a new, fast-acting, specific, single-molecule reversal agent (antidote) and present in vivo data for the first time, including efficacy, reversibility, preliminary safety, and initial biodistribution studies. HEX01 contains multiple thrombin-binding aptamers appended on an RNA origami. It exhibits excellent anticoagulation activity in vitro and in vivo. The new single-molecule, DNA antidote (HEX02) reverses anticoagulation activity of HEX01 in human plasma within 30 s in vitro and functions effectively in a murine liver laceration model. Biodistribution studies of HEX01 in whole mice using ex vivo imaging show accumulation mainly in the liver over 24 h and with 10-fold lower concentrations in the kidneys. Additionally, we show that the HEX01/HEX02 system is non-cytotoxic to epithelial cell lines and non-hemolytic in vitro. Furthermore, we found no serum cytokine response to HEX01/HEX02 in a murine model. HEX01 and HEX02 represent a safe and effective coagulation control system with a fast-acting, specific reversal agent showing promise for potential drug development.

Emerging Biohybrids of Aptamer-Based Nano-Biosensing Technologies for Effective Early Cancer Detection

Cancer is a leading global cause of mortality, which underscores the imperative of early detection for improved patient outcomes. Biorecognition molecules, especially aptamers, have emerged as highly effective tools for early and accurate cancer cell identification. Aptamers, with superior versatility in synthesis and modification, offer enhanced binding specificity and stability compared with conventional antibodies. Hence, this article reviews diagnostic strategies employing aptamer-based biohybrid nano-biosensing technologies, focusing on their utility in detecting cancer biomarkers and abnormal cells. Recent developments include the synthesis of nano-aptamers using diverse nanomaterials, such as metallic nanoparticles, metal oxide nanoparticles, carbon-derived substances, and biohybrid nanostructures. The integration of these nanomaterials with aptamers significantly enhances sensitivity and specificity, promising innovative and efficient approaches for cancer diagnosis. This convergence of nanotechnology with aptamer research holds the potential to revolutionize cancer treatment through rapid, accurate, and non-invasive diagnostic methods.

Aptamer as a targeted approach towards treatment of breast cancer

Aptamers, a novel type of targeted ligand used in drug delivery, have quickly gained popularity due to their high target specificity and affinity. Different aptamer-mediated drug delivery systems, such as aptamer-drug conjugate (ApDC), aptamer-siRNA, and aptamer-functionalised nanoparticle systems, are currently being developed for the successful treatment of cancer based on the excellent properties of aptamers. These systems can decrease potential toxicity and enhance therapeutic efficacy by targeting the drug moiety. In this review, we provide an overview of recent developments in aptamer-mediated delivery systems for cancer therapy, specifically for breast cancer, and talk about the potential applications and current issues of novel aptamer-based techniques. This study in aptamer technology for breast cancer therapy highlights key aptamers targeting well-established biomarkers such as HER2, oestrogen receptor, and progesterone receptor. Additionally, we explore the potential of aptamers in overcoming various challenges such as drug resistance and improving the delivery of therapeutic agents. This review aims to provide a deeper understanding of the present aptamer-based targeted delivery applications through in-depth analysis to increase efficacy and create new therapeutic approaches that may ultimately lead to better treatment outcomes for cancer patients.

The development and technologies of RNA therapeutics

Since it was discovered for over 20 years ago, the potentiality of siRNAs in gene silencing in vitro and in vivo models has been recognized. Several studies in the new generation, molecular mechanisms, target attachment, and purification of RNA have supported the development of RNA therapeutics for a variety of applications. RNA therapeutics are growing rapidly with various platforms contributing to the standard of personalized medicine and rare disease treatment. Therefore, understanding the development and technologies of RNA therapeutics becomes a crucial point for new drug generation. Here, the primary purpose of this review is to provide a general view of six therapeutic categories that make up RNA-based therapeutic approaches, including RNA-target therapeutics, protein-targeted therapeutics, cellular reprogramming and tissues engineering, RNA-based protein replacement therapeutics, RNA-based genome editing, and RNA-based immunotherapies based on non-coding RNAs and coding RNA. Furthermore, we present an overview of the RNA strategies regarding viral approaches and nonviral approaches in designing a new generation of RNA technologies. The advantages and challenges of using RNA therapeutics are also discussed along with various approaches for RNA delivery. Therefore, this review is designed to provide updated reference evidence of RNA therapeutics in the battle against rare or difficult-to-treat diseases for researchers in this field.

Unlocking the potential of RNA-based therapeutics in the lung: current status and future directions

Awareness of RNA-based therapies has increased after the widespread adoption of mRNA vaccines against SARS-CoV-2 during the COVID-19 pandemic. These mRNA vaccines had a significant impact on reducing lung disease and mortality. They highlighted the potential for rapid development of RNA-based therapies and advances in nanoparticle delivery systems. Along with the rapid advancement in RNA biology, including the description of noncoding RNAs as major products of the genome, this success presents an opportunity to highlight the potential of RNA as a therapeutic modality. Here, we review the expanding compendium of RNA-based therapies, their mechanisms of action and examples of application in the lung. The airways provide a convenient conduit for drug delivery to the lungs with decreased systemic exposure. This review will also describe other delivery methods, including local delivery to the pleura and delivery vehicles that can target the lung after systemic administration, each providing access options that are advantageous for a specific application. We present clinical trials of RNA-based therapy in lung disease and potential areas for future directions. This review aims to provide an overview that will bring together researchers and clinicians to advance this burgeoning field.

Inhalation of an RNA aptamer that selectively binds extracellular histones protects from acute lung injury

Acute lung injury (ALI) is a syndrome of acute inflammation, barrier disruption, and hypoxemic respiratory failure associated with high morbidity and mortality. Diverse conditions lead to ALI, including inhalation of toxic substances, aspiration of gastric contents, infection, and trauma. A shared mechanism of acute lung injury is cellular toxicity from damage-associated molecular patterns (DAMPs), including extracellular histones. We recently described the selection and efficacy of a histone-binding RNA aptamer (HBA7). The current study aimed to identify the effects of extracellular histones in the lung and determine if HBA7 protected mice from ALI. Histone proteins decreased metabolic activity, induced apoptosis, promoted proinflammatory cytokine production, and caused endothelial dysfunction and platelet activation in vitro. HBA7 prevented these effects. The oropharyngeal aspiration of histone proteins increased neutrophil and albumin levels in bronchoalveolar lavage fluid (BALF) and precipitated neutrophil infiltration, interstitial edema, and barrier disruption in alveoli in mice. Similarly, inhaling wood smoke particulate matter, as a clinically relevant model, increased lung inflammation and alveolar permeability. Treatment by HBA7 alleviated lung injury in both models of ALI. These findings demonstrate the pulmonary delivery of HBA7 as a nucleic acid-based therapeutic for ALI.

Rapid production of multimeric RNA aptamers stabilized by a designed pseudo-circular structure in E. coli

RNA aptamers bind specifically and selectively to various macromolecules, cell surfaces, and viruses and find broad applications as biosensors, diagnostics, and in therapeutic treatments and drug delivery. Currently, RNA aptamer production is via in vitro methods. Herein, a new E. coli-based approach has been demonstrated for the rapid production of multimeric RNA aptamer transcripts that are protected from degradation by burying the 5' and 3' ends of the transcript in a designed double-stranded spacer. Multimeric and fluorescent RNA aptamers were produced stably in vivo and readily isolated from RNase III-deficient cells, and their full functionalities were shown by binding assays and fluorescence measurements. This approach shows promise as a rapid and scalable bioprocess for the production of RNA aptamers at low cost.

Evolution of Cell-Type-Specific RNA Aptamers via Live Cell-Based SELEX

Live cell-based SELEX (Systematic Evolution of Ligand EXponential enrichment) is a promising approach for identifying aptamers that can selectively bind to a cell-surface receptor or recognize a particular target cell population. In particular, it offers a facile selection strategy for some special cell-surface proteins that are originally glycosylated or heavily posttranslationally modified and are unavailable in their native/active conformation after in vitro expression and purification. In this chapter, we describe a generalized procedure for evolution of cell type-specific RNA aptamers targeting a cell membrane bound target by combining the live cell-based SELEX strategy with high-throughput sequencing (HTS) and bioinformatics analysis.

Inhibition of α-Synuclein Seeding-Dependent Aggregation by ssDNA Aptamers Specific to C-Terminally Truncated α-Synuclein Fibrils

Neuropathologically, Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are characterized by the accumulation of insoluble aggregates of α-synuclein (α-syn) in the Lewy bodies (LBs). In addition to full-length α-syn fibrils, C-terminally truncated α-syn is also abundant in the LBs that acts as seeds and facilitates the aggregation of the full-length α-syn in vitro and in vivo and induces toxicity. Hence, identifying molecules that can inhibit the seeding activity of these truncated forms is of great importance. Here, we report the first in vitro selection of aptamers targeting the fibrillar forms of different C-terminally truncated α-syn using systematic evolution by an exponential enrichment method followed by quantitative high-throughput DNA sequencing. We identify a panel of aptamers that bound with high specificity to different truncated forms of α-syn fibrils with no cross-reactivity toward other amyloid fibrils. Interestingly, two of the aptamers (named Apt11 and Apt15) show higher affinity to most C-terminally truncated forms of α-syn fibrils with an evident inhibition of α-syn-seeded aggregation in vitro by Apt11. This inhibition is further confirmed by circular dichroism, Congo red binding assay, and electronic microscopy. Moreover, Apt11 is also found to reduce the insoluble phosphorylated form of α-syn at Ser-129 (pS129-α-syn) in the cell model and also can inhibit α-syn aggregation using RT-QuIC reactions seeded with brain homogenates extracted from patients affected by PD. The aptamers discovered in this study represent potential useful tools for research and diagnostics or therapy toward PD and DLB.

Aptamers Regulating the Hemostasis System

The hemostasis system is a complex structure that includes the fibrinolysis system, and Yes this is correct coagulation and anticoagulation parts. Due to the multicomponent nature, it becomes relevant to study the key changes in the functioning of signaling pathways, and develop new diagnostic methods and modern drugs with high selectivity. One of the ways to solve this problem is the development of molecular recognition elements capable of blocking one of the hemostasis systems and/or activating another. Aptamers can serve as ligands for targeting specific clinical needs, promising anticoagulants with minor side effects and significant biological activity. Aptamers with several clotting factors and platelet proteins are used for the treatment of thrombosis. This review is focused on the aptamers used for the correction of the hemostasis system, and their structural and functional features. G-rich nucleic acid aptamers, mostly versatile G-quadruplexes, recognize different components of the hemostasis system and are capable of correcting the functioning.

Aptamers: A prospective tool for infectious diseases diagnosis

It is well known that people's health is seriously threatened by various pathogens (such as Mycobacterium tuberculosis, Treponema pallidum, Novel coronavirus, HIV, Mucor, etc.), which leads to heavy socioeconomic burdens. Therefore, early and accurate pathogen diagnosis is essential for timely and effective therapies. Up to now, diagnosing human contagious diseases at molecule and nano levels is remarkably difficult owing to insufficient valid probes when it comes to determining the biological markers of pathogens. Aptamers are a set of high‐specificity and high‐sensitivity plastic oligonucleotides screened in vitro via the selective expansion of ligands by exponential enrichment (SELEX). With the advent of aptamer‐based technologies, their merits have aroused mounting academic interest. In recent years, as new detection and treatment tools, nucleic acid aptamers have been extensively utilized in the field of biomedicine, such as pathogen detection, new drug development, clinical diagnosis, nanotechnology, etc. However, the traditional SELEX method is cumbersome and has a long screening cycle, and it takes several months to screen out aptamers with high specificity. With the persistent development of SELEX‐based aptamer screening technologies, the application scenarios of aptamers have become more and more extensive. The present research briefly reviews the research progress of nucleic acid aptamers in the field of biomedicine, especially in the diagnosis of contagious diseases.

Systematic bio-fabrication of aptamers and their applications in engineering biology

Aptamers are single-stranded DNA or RNA molecules that have high affinity and selectivity to bind to specific targets. Compared to antibodies, aptamers are easy to in vitro synthesize with low cost, and exhibit excellent thermal stability and programmability. With these features, aptamers have been widely used in biology and medicine-related fields. In the meantime, a variety of systematic evolution of ligands by exponential enrichment (SELEX) technologies have been developed to screen aptamers for various targets. According to the characteristics of targets, customizing appropriate SELEX technology and post-SELEX optimization helps to obtain ideal aptamers with high affinity and specificity. In this review, we first summarize the latest research on the systematic bio-fabrication of aptamers, including various SELEX technologies, post-SELEX optimization, and aptamer modification technology. These procedures not only help to gain the aptamer sequences but also provide insights into the relationship between structure and function of the aptamers. The latter provides a new perspective for the systems bio-fabrication of aptamers. Furthermore, on this basis, we review the applications of aptamers, particularly in the fields of engineering biology, including industrial biotechnology, medical and health engineering, and environmental and food safety monitoring. And the encountered challenges and prospects are discussed, providing an outlook for the future development of aptamers.

Connective tissue growth factor-targeting DNA aptamer suppresses pannus formation as diagnostics and therapeutics for rheumatoid arthritis

Connective tissue growth factor (CTGF) has been recently acknowledged as an ideal biomarker in the early disease course, participating in the pathogenesis of pannus formation in rheumatoid arthritis (RA). However, existing approaches for the detection of or antagonist targeting CTGF are either lacking or unsatisfactory in the diagnosis and treatment of RA. To address this, we synthesized and screened high-affinity single-stranded DNA aptamers targeting CTGF through a protein-based SELEX procedure. The structurally optimized variant AptW2-1-39-PEG was characterized thoroughly for its high-affinity (KD 7.86 nM), sensitivity (minimum protein binding concentration, 2 ng), specificity (negative binding to other biomarkers of RA), and stability (viability-maintaining duration in human serum, 48 h) properties using various biochemical and biophysical assays. Importantly, we showed the antiproliferative and antiangiogenic activities of the aptamers obtained using functional experiments and further verified the therapeutic effect of the aptamers on joint injury and inflammatory response in collagen-induced arthritis (CIA) mice, thus advancing this study into actual therapeutic application. Furthermore, we revealed that the binding within AptW2-1-39-PEG/CTGF was mediated by the thrombospondin 1 (TSP1) domain of CTGF using robust bioinformatics tools together with immunofluorescence. In conclusion, our results revealed a novel aptamer that holds promise as an additive or alternative approach for CTGF-targeting diagnostics and therapeutics for RA.

Engineering Aptamers with Selectively Enhanced Biostability in the Tumor Microenvironment

Aptamers are emerging as promising molecular tools in cancer-targeted theranostics. Improving their in vivo stability has been a critical issue in promoting clinical translation, but such efforts could lead to more serious side effects resulting from prolonged retention in healthy organs. To address this problem, we developed an environment-responsive stabilization strategy for the selective enhancement of aptamer biostability in the tumor microenvironment (TME). Briefly, by means of the end extension of an ATP-responsive protection (ARP) module, the designed aptamer could be protected from nuclease degradation through the specific incorporation of ATP. Based on our in vivo results, this ARP-aptamer probe was effectively accumulated in tumors via aptamer-based molecular recognition. It showed selectively prolonged tumor retention time, but rapid digestion in healthy organs. Our strategy should provide a new paradigm for the development of organ-specific nucleic acid-based imaging and therapeutic agents.

Exploring the Utility of ssDNA Aptamers Directed against Snake Venom Toxins as New Therapeutics for Snakebite Envenoming

Snakebite is a neglected tropical disease that causes considerable death and disability in the tropical world. Although snakebite can cause a variety of pathologies in victims, haemotoxic effects are particularly common and are typically characterised by haemorrhage and/or venom-induced consumption coagulopathy. Antivenoms are the mainstay therapy for treating the toxic effects of snakebite, but despite saving thousands of lives annually, these therapies are associated with limited cross-snake species efficacy due to venom variation, which ultimately restricts their therapeutic utility to particular geographical regions. In this study, we sought to explore the potential of ssDNA aptamers as toxin-specific inhibitory alternatives to antibodies. As a proof of principle model, we selected snake venom serine protease toxins, which are responsible for contributing to venom-induced coagulopathy following snakebite envenoming, as our target. Using SELEX technology, we selected ssDNA aptamers against recombinantly expressed versions of the fibrinogenolytic SVSPs ancrod from the venom of C. rhodostoma and batroxobin from B. atrox. From the resulting pool of specific ssDNA aptamers directed against each target, we identified candidates that exhibited low nanomolar binding affinities to their targets. Downstream aptamer-linked immobilised sorbent assay, fibrinogenolysis, and coagulation profiling experiments demonstrated that the candidate aptamers were able to recognise native and recombinant SVSP toxins and inhibit the toxin- and venom-induced prolongation of plasma clotting times and the consumption of fibrinogen, with inhibitory potencies highly comparable to commercial polyvalent antivenoms. Our findings demonstrate that rationally selected toxin-specific aptamers can exhibit broad in vitro cross-reactivity against toxin isoforms found in different snake venoms and are capable of inhibiting toxins in pathologically relevant in vitro and ex vivo models of venom activity. These data highlight the potential utility of ssDNA aptamers as novel toxin-inhibiting therapeutics of value for tackling snakebite envenoming.

On-chip selection of adenosine aptamer using graphene oxide-coated magnetic nanoparticles

Systematic evolution of ligands by exponential enrichment (SELEX) is a method that is generally used for developing aptamers, which have arisen the promising alternatives for antibodies. However, conventional SELEX methods have limitations, such as a limited selection of target molecules, time-consuming and complex fabrication processes, and labor-intensive processes, which result in low selection yields. Here, we used (i) graphene oxide (GO)-coated magnetic nanoparticles in the selection process for separation and label-free detection and (ii) a multilayered microfluidic device manufactured using a three-dimensionally printed mold that is equipped with automated control valves to achieve precise fluid flows. The developed on-chip aptamer selection device and GO-coated magnetic nanoparticles were used to screen aptamer candidates for adenosine in eight cycles of the selection process within approximately 2 h for each cycle. Based on results from isothermal titration calorimetry, an aptamer with a dissociation constant of 18.6 ± 1.5 μM was selected. Therefore, the on-chip platform based on GO-coated magnetic nanoparticles provides a novel label-free screening technology for biosensors and micro/nanobiotechnology for achieving high-quality aptamers.

Aptamers-Diagnostic and Therapeutic Solution in SARS-CoV-2

The SARS-CoV-2 virus is currently the most serious challenge to global public health. Its emergence has severely disrupted the functioning of health services and the economic and social situation worldwide. Therefore, new diagnostic and therapeutic tools are urgently needed to allow for the early detection of the SARS-CoV-2 virus and appropriate treatment, which is crucial for the effective control of the COVID-19 disease. The ideal solution seems to be the use of aptamers—short fragments of nucleic acids, DNA or RNA—that can bind selected proteins with high specificity and affinity. They can be used in methods that base the reading of the test result on fluorescence phenomena, chemiluminescence, and electrochemical changes. Exploiting the properties of aptamers will enable the introduction of rapid, sensitive, specific, and low-cost tests for the routine diagnosis of SARS-CoV-2. Aptamers are excellent candidates for the development of point-of-care diagnostic devices and are potential therapeutic tools for the treatment of COVID-19. They can effectively block coronavirus activity in multiple fields by binding viral proteins and acting as carriers of therapeutic substances. In this review, we present recent developments in the design of various types of aptasensors to detect and treat the SARS-CoV-2 infection.

Anti-HIV Aptamers: Challenges and Prospects

Human Immunodeficiency Virus (HIV) infection continues to be a significant health burden in many countries around the world. Current HIV treatment through a combination of different antiretroviral drugs (cART) effectively suppresses viral replication, but drug resistance and crossresistance are significant challenges. This has prompted the search for novel targets and agents, such as nucleic acid aptamers. Nucleic acid aptamers are oligonucleotides that attach to the target sites with high affinity and specificity. This review provides a target-by-target account of research into anti-HIV aptamers and summarises the challenges and prospects of this therapeutic strategy, specifically in the unique context of HIV infection.

Aptamers: an emerging navigation tool of therapeutic agents for targeted cancer therapy

Chemotherapeutic agents have been used for the treatment of numerous cancers, but due to poor selectivity and severe systemic side effects, their clinical application is limited. Single-stranded DNA (ssDNA) or RNA aptamers could conjugate with highly toxic chemotherapy drugs, toxins, therapeutic RNAs or other molecules as novel aptamer-drug conjugates (ApDCs), which are capable of significantly improving the therapeutic efficacy and reducing the systemic toxicity of drugs and have great potential in clinics for targeted cancer therapy. In this review, we have comprehensively discussed and summarized the current advances in the screening approaches of aptamers for specific cancer biomarker targeting and development of the aptamer-drug conjugate strategy for targeted drug delivery. Moreover, considering the huge progress in artificial intelligence (AI) for protein and RNA structure predictions, automatic design of aptamers using deep/machine learning techniques could be a powerful approach for rapid and precise construction of biopharmaceutics (i.e., ApDCs) for application in cancer targeted therapy.

Oligonucleotide aptamers: Recent advances in their screening, molecular conformation and therapeutic applications

Aptamers are single stranded oligonucleotides with specific recognition and binding ability to target molecules, which can be obtained by Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Aptamers have the advantages of low molecular weight, low immunogenicity, easy modification and high stability. They play promising role in promoting food safety, monitoring the environment and basic research, especially in clinical diagnosis and therapeutic drugs. To date, great achievements regarding the selection, modifications and application of aptamers have been made. However, since it is still a challenge to obtain aptamers with high affinity in a more effective way, few aptamer-based products have already successfully entered into clinical use. This review aims to provide a thorough overview of the latest advances in this rapidly developing field, focusing on aptamer screening methods for different targets, the structure of the interaction between aptamers and target substances, and the challenges and potential of current therapeutic aptamers.

Therapeutic delivery of siRNA with polymeric carriers to down-regulate STAT5A expression in high-risk B-cell acute lymphoblastic leukemia (B-ALL)

Overexpression and persistent activation of STAT5 play an important role in the development and progression of acute lymphoblastic leukemia (ALL), the most common pediatric cancer. Small interfering RNA (siRNA)-mediated downregulation of STAT5 represents a promising therapeutic approach for ALL to overcome the limitations of current treatment modalities such as high relapse rates and poor prognosis. However, to effectively transport siRNA molecules to target cells, development of potent carriers is of utmost importance to surpass hurdles of delivery. In this study, we investigated the use of lipopolymers as non-viral delivery systems derived from low molecular weight polyethylenimines (PEI) substituted with lauric acid (Lau), linoleic acid (LA) and stearic acid (StA) to deliver siRNA molecules to ALL cell lines and primary samples. Among the lipid-substituted polymers explored, Lau- and LA-substituted PEI displayed excellent siRNA delivery to SUP-B15 and RS4;11 cells. STAT5A gene expression was downregulated (36-92%) in SUP-B15 and (32%) in RS4;11 cells using the polymeric delivery systems, which consequently reduced cell growth and inhibited the formation of colonies in ALL cells. With regard to ALL primary cells, siRNA-mediated STAT5A gene silencing was observed in four of eight patient cells using our leading polymeric delivery system, 1.2PEI-Lau8, accompanied by the significant reduction in colony formation in three of eight patients. In both BCR-ABL positive and negative groups, three of five patients demonstrated marked cell growth inhibition in both MTT and trypan blue exclusion assays using 1.2PEI-Lau8/siRNA complexes in comparison with their control siRNA groups. Three patient samples did not show any positive results with our delivery systems. Differential therapeutic responses to siRNA therapy observed in different patients could result from variable genetic profiles and patient-to-patient variability in delivery. This study supports the potential of siRNA therapy and the designed lipopolymers as a delivery system in ALL therapy.

Review of Contemporary Self-Assembled Systems for the Controlled Delivery of Therapeutics in Medicine

The novel and unique design of self-assembled micro and nanostructures can be tailored and controlled through the deep understanding of the self-assembly behavior of amphiphilic molecules. The most commonly known amphiphilic molecules are surfactants, phospholipids, and block copolymers. These molecules present a dual attraction in aqueous solutions that lead to the formation of structures like micelles, hydrogels, and liposomes. These structures can respond to external stimuli and can be further modified making them ideal for specific, targeted medical needs and localized drug delivery treatments. Biodegradability, biocompatibility, drug protection, drug bioavailability, and improved patient compliance are among the most important benefits of these self-assembled structures for drug delivery purposes. Furthermore, there are numerous FDA-approved biomaterials with self-assembling properties that can help shorten the approval pathway of efficient platforms, allowing them to reach the therapeutic market faster. This review focuses on providing a thorough description of the current use of self-assembled micelles, hydrogels, and vesicles (polymersomes/liposomes) for the extended and controlled release of therapeutics, with relevant medical applications. FDA-approved polymers, as well as clinically and commercially available nanoplatforms, are described throughout the paper.

Aptamer-Based Lateral Flow Biosensor for Rapid Detection of Salivary Cortisol

We have developed a disposable point-of-care (POC) aptamer-based biosensor for the detection of salivary cortisol. Nonstressful and noninvasive sampling of saliva compared to that of blood makes saliva an attractive biological matrix in developing POC devices for biomarker monitoring. Aptamers are attractive as recognition elements for multiple reasons, including their specific chemical synthesis, high stability, lack of immunogenicity, and cell-free evolution. A duplex aptamer conjugated to the surface of Au nanoparticles (AuNPs) by Au-S bonds is utilized as the sensor probe in a lateral flow assay (LFA) device. The addition of saliva samples containing cortisol makes the cortisol-aptamer undergo conformational changes and dissociate from the capture probe. Increasing cortisol concentration in the dispensed saliva sample results in increased dissociation and leads to increased binding of AuNP conjugate on the test line. Therefore, the color intensity of the test line on the LFA is a direct function of the concentration of cortisol in saliva. This simple and fast method provides detection in the cortisol range of ∼0.5-15 ng/mL, which is in the clinically accepted range for salivary cortisol. The limit of detection was 0.37 ng/mL, and the accuracy was confirmed by enzyme-linked immunosorbent assay (ELISA) testing results. High selectivity was observed for salivary cortisol against other closely related steroids and stress biomarkers present in saliva.

Recent advances in understanding oligonucleotide aptamers and their applications as therapeutic agents

The innovative discovery of aptamers was based on target-specific treatment in clinical diagnostics and therapeutics. Aptamers are synthetic, single-stranded oligonucleotides, simply described as chemical antibodies, which can bind to diverse targets with high specificity and affinity. Aptamers are synthesized by the SELEX technique, and possess distinctive properties as small size (10-50 kDa), higher stability, easy manufacture and less immunogenicity. These oligonucleotides are easily degraded by nucleases, so require some important modifications like capping and incorporation of modified nucleotides. RNA aptamers can be modified chemically on 2' positions using -NH3, -F, -deoxy, or -OMe groups to enhance their nuclease resistance. Aptamers have been employed for multiple purposes, as direct drugs or aptamer-drug conjugates targeted against different diseased cells. Different aptamer-conjugated nanovehicles (e.g., micelles, liposomes, silica nano-shells) have been designed to transport diverse anticancer-drugs like doxorubicin and cisplatin in bulk to minimize systemic cytotoxicity. Some drug-loaded nanovehicles (up to 97% loading capacity) and conjugated with specific aptamer resulted in more than 60% tumor inhibition as compared to unconjugated drug-loaded nanovehicles which showed only 31% cancer inhibition. In addition, aptamers have been widely used in basic research, food safety, environmental monitoring, clinical diagnostics and therapeutics. Different FDA-approved RNA and DNA aptamers are now available in the market, used for the treatment of diverse diseases, especially cancer. These aptamers include Macugen, Pegaptanib, etc. Despite a good progress in aptamer use, the present-day chemotherapeutics and drug targeting systems still face great challenges. Here in this review article, we are discussing nucleic acid aptamers, preparation, role in the transportation of different nanoparticle vehicles and their applications as therapeutic agents.

A Novel DNA Aptamer Targeting S100P Induces Antitumor Effects in Colorectal Cancer Cells

Colorectal cancer (CRC) is a prevalent malignancy with poor prognosis and survival. As a Ca²⁺ binding protein, S100P plays a role in calcium-dependent signal transduction pathways that involve in diverse biological processes. Our previous studies have shown that S100P is overexpressed in CRC tissues and regulates cell growth, invasion, and metastasis in CRC. Therefore, S100P is expected to be an effective target for CRC therapy. Aptamers are short single-stranded oligonucleotides that could serve as specific and high-affinity probes to a wide range of target molecules for therapeutic purposes. In this study, we generated a novel DNA aptamer against S100P (AptS100P-1) by way of the SELEX process and high-throughput sequencing. The binding assay showed that AptS100P-1 had a high affinity for S100P protein. Further experiments indicated that AptS100P-1 is relatively stable in a cell culture system and could be used in flow cytometry analysis, dot blot assay, and fluorescence microscopy analysis to detect S100P. Moreover, AptS100P-1 was capable of binding to cells and had an inhibitory effect on CRC cell growth in vitro and in vivo. Also, AptS100P-1 inhibited the migration and epithelial-mesenchymal transition of CRC cells expressing S100P. These results indicate a novel DNA aptamer targeting S100P, which might be a potential therapeutic strategy for targeting S100P against S100P-expressing CRC.

Aptamers in Drug Design: An Emerging Weapon to Fight a Losing Battle

Implementation of novel and biocompatible polymers in drug design is an emerging and rapidly growing area of research. Even though we have a large number of polymer materials for various applications, the biocompatibility of these materials remains as a herculean task for researchers. Aptamers provide a vital and efficient solution to this problem. They are usually small (ranging from 20 to 60 nucleotides, single-stranded DNA or RNA oligonucleotides which are capable of binding to molecules possessing high affinity and other properties like specificity. This review focuses on different aspects of Aptamers in drug discovery, starting from its preparation methods and covering the recent scenario reported in the literature regarding their use in drug discovery. We address the limitations of Aptamers and provide valuable insights into their future potential in the areas regarding drug discovery research. Finally, we explained the major role of Aptamers like medical imaging techniques, application as synthetic antibodies, and the most recent application, which is in combination with nanomedicines.

Current methods for stress marker detection in saliva

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Introduction of relevant biomarkers in stress conditions.

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Reference ranges of biomarkers in normal conditions.

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Saliva as easy-accessible specimen.

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Review of analytical methods for biomarker determination in saliva.

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Possibilities for design of point-of-care devices.

Stress and stress-related diseases are leading to drastic consequences in private and professional life. Therefore, the need for stress prevention strategies is of personal and economic interest. Especially during the recent period related to covid-19 outbreak and lock-down, an ongoing discussion of increasing stress etiology is reported. Biomarker analysis may help to assist diagnosis and classification of stress-related diseases and therefore support therapeutical decisions. Due to its non-invasive sampling, the analysis of saliva has become highly attractive compared to the detection methods in other specimen. This review article summarizes the status of research, innovative approaches, and trends. Scientific literature published since 2011 was excerpted with concentration on the detection of up to seven promising marker substances. Most often reported cortisol represents the currently best evaluated stress marker, while norepinephrine (noradrenaline) or its metabolite 3-methoxy-4-hydroxyphenylglycol is also a quite commonly considered stress marker. Other complementary stress marker candidates are testosterone, dehydroepiandrosterone (DHEA) and its sulfonated analogue DHEA-S, alpha-amylase, secretory immunoglobulin A, and chromogranin A. Several working groups are researching in the field of stress marker detection to develop reliable, fast, and affordable methods. Analytical methods reported mainly focused on immunological and electrochemical as well as chromatographic methods hyphenated to mass spectrometric detection to yield the required detection limits.

Nucleic acid-based therapy for coronavirus disease 2019

The coronavirus disease 2019 (COVID-19), the pandemic that originated in China has already spread into more than 190 countries, resulting in huge loss of human life and many more are at the stake of losing it; if not intervened with the best therapeutics to contain the disease. For that aspect, various scientific groups are continuously involved in the development of an effective line of treatment to control the novel coronavirus from spreading rapidly. Worldwide scientists are evaluating various biomolecules and synthetic inhibitors against COVID-19; where the nucleic acid-based molecules may be considered as potential drug candidates. These molecules have been proved potentially effective against SARS-CoV, which shares high sequence similarity with SARS-CoV-2. Recent advancements in nucleic acid-based therapeutics are helpful in targeted drug delivery, safely and effectively. The use of nucleic acid-based molecules also known to regulate the level of gene expression inside the target cells. This review mainly focuses on various nucleic acid-based biologically active molecules and their therapeutic potentials in developing vaccines for SARS-CoV-2.

Internalized Functional DNA Aptamers as Alternative Cancer Therapies

Despite major advances, cancer remains one of the largest burdens of disease worldwide. One reason behind this is that killing tumor cells without affecting healthy surrounding tissue remains a largely elusive prospect, despite the widespread availability of cytotoxic chemotherapeutic agents. To meet these modern healthcare requirements, it is essential to develop precision therapeutics that minimise off-target side-effects for various cancer types. To this end, highly specific molecular targeting agents against cancer are of great interest. These agents may work by targeting intracellular signalling pathways following receptor binding, or via internalization and targeting to specific subcellular compartments. DNA aptamers represent a promising molecular tool in this arena that can be used for both specific cell surface targeting and subsequent internalization and can also elicit a functional effect upon internalization. This review examines various cancer targeting cell-internalizing aptamers, with a particular focus towards functional aptamers that do not require additional conjugation to nanoparticles or small molecules to elicit a biological response. With a deeper understanding and precise exploitation of cancer specific molecular pathways, functional intracellular DNA aptamers may be a powerful step towards more widespread development of precision therapeutics.

A photo-triggerable aptamer nanoswitch for spatiotemporal controllable siRNA delivery

A photo-triggerable aptamer nanoswitch was proposed for spatiotemporal regulation of siRNA delivery. Recognition between AS1411 and nucleolin was effectively blocked by a photo-labile complementary oligonucleotide, which could be reactivated with photo-irradiation, resulting in efficient tumor-targeted siRNA internalization and gene silencing in vitro and in vivo.

N 1-Methylpseudouridine substitution enhances the performance of synthetic mRNA switches in cells

Synthetic messenger RNA (mRNA) tools often use pseudouridine and 5-methyl cytidine as substitutions for uridine and cytidine to avoid the immune response and cytotoxicity induced by introducing mRNA into cells. However, the influence of base modifications on the functionality of the RNA tools is poorly understood. Here we show that synthetic mRNA switches containing N¹-methylpseudouridine (m1Ψ) as a substitution of uridine substantially out-performed all other modified bases studied, exhibiting enhanced microRNA and protein sensitivity, better cell-type separation ability, and comparably low immune stimulation. We found that the observed phenomena stem from the high protein expression from m1Ψ containing mRNA and efficient translational repression in the presence of target microRNAs or proteins. In addition, synthetic gene circuits with m1Ψ significantly improve performance in cells. These findings indicate that synthetic mRNAs with m1Ψ modification have enormous potentials in the research and application of biofunctional RNA tools.

Metal-Organic Framework Nanocarriers for Drug Delivery in Biomedical Applications

Investigation of metal-organic frameworks (MOFs) for biomedical applications has attracted much attention in recent years. MOFs are regarded as a promising class of nanocarriers for drug delivery owing to well-defined structure, ultrahigh surface area and porosity, tunable pore size, and easy chemical functionalization. In this review, the unique properties of MOFs and their advantages as nanocarriers for drug delivery in biomedical applications were discussed in the first section. Then, state-of-the-art strategies to functionalize MOFs with therapeutic agents were summarized, including surface adsorption, pore encapsulation, covalent binding, and functional molecules as building blocks. In the third section, the most recent biological applications of MOFs for intracellular delivery of drugs, proteins, and nucleic acids, especially aptamers, were presented. Finally, challenges and prospects were comprehensively discussed to provide context for future development of MOFs as efficient drug delivery systems.

Targeting the RNA-Binding Protein QKI in Myeloid Cells Ameliorates Macrophage-Induced Renal Interstitial Fibrosis

In the pathophysiologic setting of acute and chronic kidney injury, the excessive activation and recruitment of blood-borne monocytes prompts their differentiation into inflammatory macrophages, a process that leads to progressive glomerulosclerosis and interstitial fibrosis. Importantly, this differentiation of monocytes into macrophages requires the meticulous coordination of gene expression at both the transcriptional and post-transcriptional level. The transcriptomes of these cells are ultimately determined by RNA-binding proteins such as QUAKING (QKI), that define their pre-mRNA splicing and mRNA transcript patterns. Using two mouse models, namely (1) quaking viable mice (qk^v) and (2) the conditional deletion in the myeloid cell lineage using the lysozyme 2-Cre (QKI^{FL/FL;LysM-Cre} mice), we demonstrate that the abrogation of QKI expression in the myeloid cell lineage reduces macrophage infiltration following kidney injury induced by unilateral urethral obstruction (UUO). The qk^v and QKI^{FL/FL;LysM-Cre} mice both showed significant diminished interstitial collagen deposition and fibrosis in the UUO-damaged kidney, as compared to wild-type littermates. We show that macrophages isolated from QKI^{FL/FL;LysM-Cre} mice are associated with defects in pre-mRNA splicing. Our findings demonstrate that reduced expression of the alternative splice regulator QKI in the cells of myeloid lineage attenuates renal interstitial fibrosis, suggesting that inhibition of this splice regulator may be of therapeutic value for certain kidney diseases.

Avβ3 Single-Stranded DNA Aptamer Attenuates Vascular Smooth Muscle Cell Proliferation and Migration via Ras-PI3K/MAPK Pathway

OBJECTIVES

To observe the effect of avβ3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism.

BACKGROUND

Percutaneous transluminal coronary angioplasty (PTCA) is currently the preferred method for the treatment of coronary heart disease. However, vascular restenosis still occurs after PTCA treatment, severely affecting the clinical efficacy of PTCA. Integrin avβ3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism.

METHODS

In this experiment, we used systematic evolution of ligands by exponential enrichment (SELEX) to screen out avβ3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism. β3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism. β3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism. β3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism.

RESULTS

In the present study, we found that avβ3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism. P < 0.05). Avβ3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism. P < 0.05). AvP < 0.05). Av.

CONCLUSIONS

The findings suggest that avβ3 ssDNA inhibited the proliferation and migration of VSMCs by suppressing the activation of Ras-PI3K/MAPK signaling.β3 single-stranded (ss) DNA on proliferation and migration of vascular smooth muscle cells (VSMCs) and its potential mechanism.

Characterization of A Bifunctional Synthetic RNA Aptamer and A Truncated Form for Ability to Inhibit Growth of Non-Small Cell Lung Cancer

An in vitro-transcribed RNA aptamer (trans-RA16) that targets non-small cell lung cancer (NSCLC) was previously identified through in vivo SELEX. Trans-RA16 can specifically target and inhibit human NCI-H460 cells in vitro and xenograft tumors in vivo. Here, in a follow-up study, we obtained a chemically-synthesized version of this RNA aptamer (syn-RA16) and a truncated form, and compared them to trans-RA16 for abilities to target and inhibit NCI-H460 cells. The syn-RA16, preferred for drug development, was by design to differ from trans-RA16 in the extents of RNA modifications by biotin, which may affect RA16’s anti-tumor effects. We observed aptamer binding to NCI-H460 cells with K_D values of 24.75 ± 2.28 nM and 12.14 ± 1.46 nM for syn-RA16 and trans-RA16, respectively. Similar to trans-RA16, syn-RA16 was capable of inhibiting NCI-H460 cell viability in a dose-dependent manner. IC₅₀ values were 118.4 nM (n = 4) for syn-RA16 and 105.7 nM (n = 4) for trans-RA16. Further studies using syn-RA16 demonstrated its internalization into NCI-H460 cells and inhibition of NCI-H460 cell growth. Moreover, in vivo imaging demonstrated the gradual accumulation of both syn-RA16 and trans-RA16 at the grafted tumor site, and qRT-PCR showed high retention of syn-RA16 in tumor tissues. In addition, a truncated fragment of trans-RA16 (S3) was identified, which exhibited binding affinity for NCI-H460 cells with a K_D value of 63.20 ± 0.91 nM and inhibited NCI-H460 cell growth by 39.32 ± 3.25% at 150 nM. These features of the syn-RA16 and S3 aptamers should facilitate the development of a novel diagnostic or treatment approach for NSCLC in clinical settings.

At the Intersection of Biomaterials and Gene Therapy: Progress in Non-viral Delivery of Nucleic Acids

Biomaterials play a critical role in technologies intended to deliver therapeutic agents in clinical settings. Recent explosion of our understanding of how cells utilize nucleic acids has garnered excitement to develop a range of older (e.g., antisense oligonucleotides, plasmid DNA and transposons) and emerging (e.g., short interfering RNA, messenger RNA and non-coding RNAs) nucleic acid agents for therapy of a wide range of diseases. This review will summarize biomaterials-centered advances to undertake effective utilization of nucleic acids for therapeutic purposes. We first review various types of nucleic acids and their unique abilities to deliver a range of clinical outcomes. Using recent advances in T-cell based therapy as a case in point, we summarize various possibilities for utilizing biomaterials to make an impact in this exciting therapeutic intervention technology, with the belief that this modality will serve as a therapeutic paradigm for other types of cellular therapies in the near future. We subsequently focus on contributions of biomaterials in emerging nucleic acid technologies, specifically focusing on the design of intelligent nanoparticles, deployment of mRNA as an alternative to plasmid DNA, long-acting (integrating) expression systems, and in vitro/in vivo expansion of engineered T-cells. We articulate the role of biomaterials in these emerging nucleic acid technologies in order to enhance the clinical impact of nucleic acids in the near future.

Binding Characterization of Aptamer-Drug Layered Microformulations and In Vitro Release Assessment

Efficient delivery of adequate active ingredients to targeted malignant cells is critical, attributing to recurrent biophysical and biochemical challenges associated with conventional pharmaceutical delivery systems. These challenges include drug leakage, low targeting capability, high systemic cytotoxicity, and poor pharmacokinetics and pharmacodynamics. Targeted delivery system is a promising development to deliver sufficient amounts of drug molecules to target cells in a controlled release pattern mode. Aptameric ligands possess unique affinity targeting capabilities which can be exploited in the design of high pay-load drug formulations to navigate active molecules to the malignant sites. This study focuses on the development of a copolymeric and multifunctional drug-loaded aptamer-conjugated poly(lactide-co-glycolic acid)-polyethylenimine (PLGA-PEI) (DPAP) delivery system, via a layer-by-layer synthesis method, using a water-in-oil-in-water double emulsion approach. The binding characteristics, targeting capability, biophysical properties, encapsulation efficiency, and drug release profile of the DPAP system were investigated under varying conditions of ionic strength, polymer composition and molecular weight (MW), and degree of PEGylation of the synthetic core. Experimental results showed increased drug release rate with increasing buffer ionic strength. DPAP particulate system obtained the highest drug release of 50% at day 9 at 1 M NaCl ionic strength. DPAP formulation, using PLGA 65:35 and PEI MW of ∼800 Da, demonstrated an encapsulation efficiency of 78.93%, and a loading capacity of 0.1605 mg bovine serum albumin per mg PLGA. DPAP (PLGA 65:35, PEI MW∼25 kDa) formulation showed a high release rate with a biphasic release profile. Experimental data depicted a lower targeting power and reduced drug release rate for the PEGylated DPAP formulations. The outcomes from the present study lay the foundation to optimize the performance of DPAP system as an effective synthetic drug carrier for targeted delivery.

Chemical methods for the modification of RNA

RNA is often considered as being the vector for the transmission of genetic information from DNA to the protein synthesis machinery. However, besides translation RNA participates in a broad variety of fundamental biological roles such as gene expression and regulation, protein synthesis, and even catalysis of chemical reactions. This variety of function combined with intricate three-dimensional structures and the discovery of over 100 chemical modifications in natural RNAs require chemical methods for the modification of RNAs in order to investigate their mechanism, location, and exact biological roles. In addition, numerous RNA-based tools such as ribozymes, aptamers, or therapeutic oligonucleotides require the presence of additional chemical functionalities to strengthen the nucleosidic backbone against degradation or enhance the desired catalytic or binding properties. Herein, the two main methods for the chemical modification of RNA are presented: solid-phase synthesis using phosphoramidite precursors and the enzymatic polymerization of nucleoside triphosphates. The different synthetic and biochemical steps required for each method are carefully described and recent examples of practical applications based on these two methods are discussed.

G-rich VEGF aptamer as a potential inhibitor of chitin trafficking signal in emerging opportunistic yeast infection

The alarm is rang for friendly fire; Saccharomyces cerevisiae (S. cerevisiae) newfound as a fungal pathogen with an individual feature. S. cerevisiae has food safety and is not capable of producing infection but, when the host defenses are weakened, there is room for opportunistic S. cerevisiae strains to cause a health issues. Fungal diseases are challenging to treat because, unlike bacteria, the fungal are eukaryotes. Antibiotics only target prokaryotic cells, whereas compounds that kill fungi also harm the mammalian host. Small differences between mammalian and fungal cells regarding genes and proteins sequence and function make finding a drug target more challenging. Recently, Chitin synthase has been considered as a promising target for antifungal drug development as it is absent in mammals. In S. cerevisiae, CHS3, a class IV chitin synthase, produces 90% of the chitin and essential for cell growth. CHS3 from the trans-Golgi network to the plasma membrane requires assembly of the exomer complex (including proteins cargo such as CHS5, CHS6, Bach1, and Arf1). In this work, we performed SELEX (Systematic Evolution of Ligands by EXponential enrichment) as high throughput virtual screening of the RCSB data bank to find an aptamer as potential inhibit of the class IV chitin synthase of S. cerevisiae. Among all the candidates, G-rich VEGF (GVEGF) aptamer (PDB code: 2M53) containing locked sugar parts was observed as potential inhibitor of the assembly of CHS5-CHS6 exomer complex a subsequently block the chitin biosynthesis pathway as an effective anti-fungal. It was suggested from the simulation that an assembly of exomer core should begin CHS5-CHS6, not from CHS5-Bach1. It is notable that secondary structures of CHS6 and Bach1 was observed very similar, but they have only 25% identity at the amino acid sequence that exhibited different features in exomer assembly.

Aptamers and Clinical Applications

This chapter provides a brief introduction to followed by discussion of recent preclinical studies on potential aptamer drugs grouped into two broad categories, namely, “aptamer structures” and “non-ocular diseases.” Examples of aptamer-based targeting of drugs are then described. Next is an overview of the status of nearly 30 clinical trials of aptamer drugs currently listed in ClinicalTrials.gov, which is a registry and results database of publicly and privately supported clinical studies of human participants conducted around the world, and is a service of the US National Institutes of Health. This overview includes brief descriptions of each study sponsor, aptamer drug, disease(s), and type of study, as well as separate tables for completed studies, withdrawn or terminated studies, and active studies. The final section discusses Conclusions and Prospects.

Peptide-Aptamer Coassembly Nanocarrier for Cancer Therapy

We reported methionine bis-alkylated nonapeptide Wpc as an efficient siRNA vehicle previously. Herein, we report an aptamer could also spontaneously coassemble with Wpc to form uniformed nanoparticles for efficient delivery. This unique peptide-based aptamer nanocarrier showed significantly improved cell penetration and antiproliferation effect with high biocompatibility toward various cancer cell lines.

Involvement of long non-coding RNA HULC (highly up-regulated in liver cancer) in pathogenesis and implications for therapeutic intervention

INTRODUCTION

HULC (highly upregulated in liver cancer) is a long non-coding RNA (lncRNA) which is, as its name suggests, highly upregulated in hepatocellular carcinoma and in several other cancers. Increased HULC expression levels are strongly associated with clinicopathologic features such as tumor stages and overall survival and is a driver of tumor proliferation, migration, and invasion. Areas covered: This review addresses the discovery of HULC and discusses the consequences of HULC deregulation in cancer, the underlying molecular mechanisms and the potential of HULC as a biomarker and therapeutic target. Expert opinion: HULC is a promising candidate as a therapeutic target in cancer; however, more studies are necessary to further elucidate the underlying molecular mechanism(s), especially in cancer types other than hepatocellular carcinomas. Future studies that focus on an optimized HULC-targeting approach are necessary to clarify the best strategy to target this lncRNA in vivo and in patients.