Genetic Disease and Therapy

Mitochondrial endogenous substance transport-inspired nanomaterials for mitochondria-targeted gene delivery

Mitochondrial genome (mtDNA) independent of nuclear gene is a set of double-stranded circular DNA that encodes 13 proteins, 2 ribosomal RNAs and 22 mitochondrial transfer RNAs, all of which play vital roles in functions as well as behaviors of mitochondria. Mutations in mtDNA result in various mitochondrial disorders without available cures. However, the manipulation of mtDNA via the mitochondria-targeted gene delivery faces formidable barriers, particularly owing to the mitochondrial double membrane. Given the fact that there are various transport channels on the mitochondrial membrane used to transfer a variety of endogenous substances to maintain the normal functions of mitochondria, mitochondrial endogenous substance transport-inspired nanomaterials have been proposed for mitochondria-targeted gene delivery. In this review, we summarize mitochondria-targeted gene delivery systems based on different mitochondrial endogenous substance transport pathways. These are categorized into mitochondrial steroid hormones import pathways-inspired nanomaterials, protein import pathways-inspired nanomaterials and other mitochondria-targeted gene delivery nanomaterials. We also review the applications and challenges involved in current mitochondrial gene editing systems. This review delves into the approaches of mitochondria-targeted gene delivery, providing details on the design of mitochondria-targeted delivery systems and the limitations regarding the various technologies. Despite the progress in this field is currently slow, the ongoing exploration of mitochondrial endogenous substance transport and mitochondrial biological phenomena may act as a crucial breakthrough in the targeted delivery of gene into mitochondria and even the manipulation of mtDNA.

In Utero Gene Therapy and its Application in Genetic Hearing Loss

For monogenic genetic diseases, in utero gene therapy (IUGT) shows the potential for early prevention against irreversible and lethal pathological changes. Moreover, animal models have also demonstrated the effectiveness of IUGT in the treatment of coagulation disorders, hemoglobinopathies, neurogenetic disorders, and metabolic and pulmonary diseases. For major alpha thalassemia and severe osteogenesis imperfecta, in utero stem cell transplantation has entered the phase I clinical trial stage. Within the realm of the inner ear, genetic hearing loss significantly hampers speech, cognitive, and intellectual development in children. Nowadays, gene therapies offer substantial promise for deafness, with the success of clinical trials in autosomal recessive deafness 9 using AAV-OTOF gene therapy. However, the majority of genetic mutations that cause deafness affect the development of cochlear structures before the birth of fetuses. Thus, gene therapy before alterations in cochlear structure leading to hearing loss has promising applications. In this review, addressing advances in various fields of IUGT, the progress, and application of IUGT in the treatment of genetic hearing loss are focused, in particular its implementation methods and unique advantages.

Spherical nucleic acids: emerging amplifiers for therapeutic nanoplatforms

Gene therapy is a revolutionary treatment approach in the 21st century, offering significant potential for disease prevention and treatment. However, the efficacy of gene delivery is often compromised by the inherent challenges of gene properties and vector-related defects. It is crucial to explore ways to enhance the curative effect of gene drugs and achieve safer, more widespread, and more efficient utilization, which represents a significant challenge in amplification gene therapy advancements. Spherical nucleic acids (SNAs), with their unique physicochemical properties, are considered an innovative solution for scalable gene therapy. This review aims to comprehensively explore the amplifying contributions of SNAs in gene therapy and emphasize the contribution of SNAs to the amplification effect of gene therapy from the aspects of structure, application, and recent clinical translation - an aspect that has been rarely reported or explored thus far. We begin by elucidating the fundamental characteristics and scaling-up properties of SNAs that distinguish them from traditional linear nucleic acids, followed by an analysis of combined therapy treatment strategies, theranostics, and clinical translation amplified by SNAs. We conclude by discussing the challenges of SNAs and provide a prospect on the amplification characteristics. This review seeks to update the current understanding of the use of SNAs in gene therapy amplification and promote further research into their clinical translation and amplification of gene therapy.

Gene therapy for monogenic disorders: challenges, strategies, and perspectives

Monogenic disorders refer to a group of human diseases caused by mutations in single genes. While disease-modifying therapies have offered some relief from symptoms and delayed progression for some monogenic diseases, most of these diseases still lack effective treatments. In recent decades, gene therapy has emerged as a promising therapeutic strategy for genetic disorders. Researchers have developed various gene manipulation tools and gene delivery systems to treat monogenic diseases. Despite this progress, concerns about inefficient delivery, persistent expression, immunogenicity, toxicity, capacity limitation, genomic integration, and limited tissue specificity still need to be addressed. This review gives an overview of commonly used gene therapy and delivery tools, along with the challenges they face and potential strategies to counter them.

GPX2 acts as an oncogene and cudraflavone C has an anti-tumor effect by suppressing GPX2-dependent Wnt/β-catenin pathway in colorectal cancer cells

Colorectal carcinoma (CRC) is a common cancer associated with poor prognosis, and cudraflavone C (Cud C) is a natural flavonol with reported anti-CRC capacity. However, the precise mechanisms underlying the anti-CRC effect require further demonstration. The aim of present study was to evaluate the impact of Cud C on the cell viability and apoptosis of CRC cells and to determine the underlying mechanisms. The Human Protein Atlas (THPA) and Gene Expression Profiling Interactive Analysis (GEPIA) databases were used to analyze the expression status of glutathione peroxidase 2 (GPX2) in CRC. Cell viability was examined using cell counting kit-8 (CCK-8) assay. Flow cytometry was utilized to evaluate apoptosis. The levels of gene transcription and protein expression of GPX2, caspase-3, cleaved caspase-3), β-catenin, and c-Myc were determined by RT-qPCR and Western blotting. Our results showed that GPX2 was overexpressed in CRC as compared to normal tissue and the extent of GPX2 overexpression is greatest in CRC when compared with other cancers according to GEPIA and THPA databases. GPX2 knockdown significantly suppressed the cell viability, induced apoptosis of CRC cell lines, and restrained the activity of Wnt/β-catenin pathway. Cud C treatment decreased cell viability, induced apoptosis in CRC cell lines, and diminished the expression level of GPX2-dependent activation of Wnt/β-catenin pathway, while such effects can be abolished by GPX2 overexpression. In conclusion, Cud C suppressed GPX2-dependent Wnt/β-catenin pathway to exert anti-CRC function.

[Development of analytics in newborn screening-from the Guthrie card to genetics]

For more than five decades, all newborns in Germany have been offered a screening examination for the early detection of congenital treatable diseases. Since its inception, about 35 million children have been screened in this way.Originally, screening exams only included early detection of phenylketonuria, which, without timely treatment, would lead to mental retardation that could no longer be corrected. The bacteriological Guthrie test allowed the detection of elevated concentrations of phenylalanine. The methods used today are the result of decades of development. They have been expanded to include tests to determine enzyme activities, immunoassays for the early detection of important hormonal disorders such as congenital hypothyroidism, and high-pressure liquid chromatography for the diagnosis of pathologic hemoglobins. The very sophisticated tandem mass spectrometry enables the simultaneous detection of amino acid and fatty acid compounds. Steroids can also be identified. The specificity can be further increased by combining tandem mass spectrometry with chromatographic pre-separation. In recent years, chemical-analytical analyses have been supplemented by genetic diagnostic methods such as quantitative or qualitative polymerase chain reaction (PCR).The current state of laboratory technology is by no means final. Both classical analytics and especially genetic methods are facing further rapid development. Although the expansion of screening is also a consequence of technical development, the inclusion of further congenital diseases is fundamentally dependent on the given therapy. But it is precisely here that many innovations are currently being investigated. Gene therapy is at the forefront of interest.

Research progress in nucleus-targeted tumor therapy

The nucleus is considered the most important organelle in the cell as it plays a central role in controlling cell reproduction, metabolism, and the cell cycle. The successful delivery of drugs into the nucleus can achieve excellent therapeutic effects, which reveals the potential of nucleus-targeted therapy in precision medicine. However, the transportation of therapeutics into the nucleus remains a significant challenge due to various biological barriers. Herein, we summarize the recent progress in the nucleus-targeted drug delivery system (NDDS). The structures of the nucleus and nuclear envelope are first described in order to understand the mechanisms by which drugs cross the nuclear envelope. Then, various drug delivery strategies based on the mechanisms and their applications are discussed. Finally, the challenges and solutions in the field of nucleus-targeted drug delivery are raised for developing a more efficient NDDS and promoting its clinical transformation.

Progress on RNA-based therapeutics for genetic diseases

RNA therapeutics inhibit the expression of specific proteins/RNAs by targeting complementary sequences of corresponding genes or encode proteins for the synthesis desired genes to treat genetic diseases. RNA-based therapeutics are categorized as oligonucleotide drugs (antisense oligonucleotides, small interfering RNA, RNA aptamers), and mRNA drugs. The antisense oligonucleotides and small interfering RNA for treatment of genetic diseases have been approved by the FDA in the United States, while RNA aptamers and mRNA drugs are still in clinical trials. Chemical modifications can be applied to RNA drugs, such as pseudouridine modification of mRNA, to reduce immunogenicity and improve the efficacy. The secure and effective delivery systems such as lipid-based nanoparticles, extracellular vesicles, and virus-like particles are under development to address stability, specificity, and safety issues of RNA drugs. This article provides an overview of the specific molecular mechanisms of eleven RNA drugs currently used for treating genetic diseases, and discusses the research progress of chemical modifications and delivery systems of RNA drugs.

Promises and challenges of cardiac organoids

Cardiovascular diseases are currently the main cause of death. The study of the pathogenesis and treatment of these diseases is still a major challenge. Traditional 2D cultured cells and animal models have certain limitations. Heart organoids as models can simulate the structure and function of the body, providing a new research strategy. This paper mainly discusses the development of organoids and their application in the study of the cardiac developmental process, drug screening and treatment of genetic and non-genetic diseases, concluding with their strengths and weaknesses.

Whole-exome sequencing applications in prenatal diagnosis of fetal bowel dilatation

This study introduced whole-exome sequencing (WES) in prenatal diagnosis of fetal bowel dilatation to improve the detection outcome when karyotype analysis and copy number variation sequencing (CNV-seq) were uninformative in detecting pathogenic variants. The work reviewed 28 cases diagnosed with fetal bowel dilatation and analyzed the results of karyotype analysis, CNV-seq, and WES. Among the 28 cases, the detection rate in cases with low risk of aneuploidy was 11.54% (3/26), which is lower than 100% (2/2) in cases with high risk of aneuploidy. Ten low-risk aneuploidy cases with isolated fetal bowel dilatation had normal genetic testing results, while the remaining 16 cases with other ultrasound abnormalities were detected for genetic variants at a rate of 18.75% (3/16). The detection rate of gene variation was 3.85% (1/26) by CNV-seq and 7.69% (2/26) by WES. This study suggested that WES could reveal more genetic risk in prenatal diagnosis of fetal bowel dilatation and has value in prenatal diagnosis to reduce birth defects.

Gene modification therapies for hereditary diseases in the fetus

Proof-of-principle disease models have demonstrated the feasibility of an intrauterine gene modification therapy (in utero gene therapy (IUGT)) approach to hereditary diseases as diverse as coagulation disorders, haemoglobinopathies, neurogenetic disorders, congenital metabolic, and pulmonary diseases. Gene addition, which requires the delivery of an integrating or episomal transgene to the target cell nucleus to be transcribed, and gene editing, where the mutation is corrected within the gene of origin, have both been used successfully to increase normal protein production in a bid to reverse or arrest pathology in utero. While most experimental models have employed lentiviral, adenoviral, and adeno-associated viral vectors engineered to efficiently enter target cells, newer models have also demonstrated the applicability of non-viral lipid nanoparticles. Amelioration of pathology is dependent primarily on achieving sustained therapeutic transgene expression, silencing of transgene expression, production of neutralising antibodies, the dilutional effect of the recipient's growth on the mass of transduced cells, and the degree of pre-existing cellular damage. Safety assessment of any IUGT strategy will require long-term postnatal surveillance of both the fetal recipient and the maternal bystander for cell and genome toxicity, oncogenic potential, immune-responsiveness, and germline mutation. In this review, we discuss advances in the field and the push toward clinical translation of IUGT.

The Regulation and Double-Edged Roles of the Deubiquitinase OTUD5

OTUD5 (OTU Deubiquitinase 5) is a functional cysteine protease with deubiquitinase activity and is a member of the ovarian tumor protease (OTU) family. OTUD5 is involved in the deubiquitination of many key proteins in various cellular signaling pathways and plays an important role in maintaining normal human development and physiological functions. Its dysfunction can affect physiological processes, such as immunity and DNA damage repair, and it can even lead to tumors, inflammatory diseases and genetic disorders. Therefore, the regulation of OTUD5 activity and expression has become a hot topic of research. A comprehensive understanding of the regulatory mechanisms of OTUD5 and its use as a therapeutic target for diseases is of great value. Herein, we review the physiological processes and molecular mechanisms of OTUD5 regulation, outline the specific regulatory processes of OTUD5 activity and expression, and link OTUD5 to diseases from the perspective of studies on signaling pathways, molecular interactions, DNA damage repair and immune regulation, thus providing a theoretical basis for future studies.

Development and applications of mRNA treatment based on lipid nanoparticles

Nucleic acid-based therapies such as messenger RNA have the potential to revolutionize modern medicine and enhance the performance of existing pharmaceuticals. The key challenges of mRNA-based therapies are delivering the mRNA safely and effectively to the target tissues and cells and controlling its release from the delivery vehicle. Lipid nanoparticles (LNPs) have been widely studied as drug carriers and are considered to be state-of-the-art technology for nucleic acid delivery. In this review, we begin by presenting the advantages and mechanisms of action of mRNA therapeutics. Then we discuss the design of LNP platforms based on ionizable lipids and the applications of mRNA-LNP vaccines for prevention of infectious diseases and for treatment of cancer and various genetic diseases. Finally, we describe the challenges and future prospects of mRNA-LNP therapeutics.

CRISPR/Cas9 therapeutics: progress and prospects

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene-editing technology is the ideal tool of the future for treating diseases by permanently correcting deleterious base mutations or disrupting disease-causing genes with great precision and efficiency. A variety of efficient Cas9 variants and derivatives have been developed to cope with the complex genomic changes that occur during diseases. However, strategies to effectively deliver the CRISPR system to diseased cells in vivo are currently lacking, and nonviral vectors with target recognition functions may be the focus of future research. Pathological and physiological changes resulting from disease onset are expected to serve as identifying factors for targeted delivery or targets for gene editing. Diseases are both varied and complex, and the choice of appropriate gene-editing methods and delivery vectors for different diseases is important. Meanwhile, there are still many potential challenges identified when targeting delivery of CRISPR/Cas9 technology for disease treatment. This paper reviews the current developments in three aspects, namely, gene-editing type, delivery vector, and disease characteristics. Additionally, this paper summarizes successful examples of clinical trials and finally describes possible problems associated with current CRISPR applications.

Current landscape of gene-editing technology in biomedicine: Applications, advantages, challenges, and perspectives

The expanding genome editing toolbox has revolutionized life science research ranging from the bench to the bedside. These “molecular scissors” have offered us unprecedented abilities to manipulate nucleic acid sequences precisely in living cells from diverse species. Continued advances in genome editing exponentially broaden our knowledge of human genetics, epigenetics, molecular biology, and pathology. Currently, gene editing‐mediated therapies have led to impressive responses in patients with hematological diseases, including sickle cell disease and thalassemia. With the discovery of more efficient, precise and sophisticated gene‐editing tools, more therapeutic gene‐editing approaches will enter the clinic to treat various diseases, such as acquired immunodeficiency sydrome (AIDS), hematologic malignancies, and even severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. These initial successes have spurred the further innovation and development of gene‐editing technology. In this review, we will introduce the architecture and mechanism of the current gene‐editing tools, including clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR‐associated nuclease‐based tools and other protein‐based DNA targeting systems, and we summarize the meaningful applications of diverse technologies in preclinical studies, focusing on the establishment of disease models and diagnostic techniques. Finally, we provide a comprehensive overview of clinical information using gene‐editing therapeutics for treating various human diseases and emphasize the opportunities and challenges.

Phase Separation Properties in Transcriptional Organization

Transcription is of great importance to stress response, fate control, and development, involving the functional cooperation of a large number of transcription factors and cofactors. Transcription machineries assemble rapidly to respond to the physiological and functional needs of cells. Recently, phase-separated biomolecular condensates have emerged as a universal biophysical basis for the spatiotemporal coordination of various cellular activities, including transcription. Here, we summarize and discuss recent advances in understanding of how phase separation contributes to RNA polymerase II (Pol II)-mediated transcriptional regulation, with a focus on the physical properties and dynamics of transcriptional condensates.

Using analogue data to substantiate long-term durability of gene therapies: a narrative review

The number of gene therapies in clinical trials and moving toward licensure is increasing. Most gene therapies are designed to achieve long-term effects, but at licensure the data to support claims of long-term durability are often limited, as long-term monitoring studies are often part of post-approval commitments by companies. Health technology assessors must therefore assess the potential for the long-term durability of a product and the potential cost-effectiveness based on the data available. The authors explored the benefit of strengthening the ability to infer durability of effect using analogue category data. Different analogue categories were assessed for the potential to substantiate claims of sustainability of effect for gene therapies by leveraging biological plausibility arguments. The authors propose a pathway for identifying potential analogues. Such a pathway should help establish plausible or theoretical long-term outcomes that can be considered in value assessments of gene therapies.

Potential of Mitochondrial Genome Editing for Human Fertility Health

Mitochondrial DNA (mtDNA) encodes vital proteins and RNAs for the normal functioning of the mitochondria. Mutations in mtDNA leading to mitochondrial dysfunction are relevant to a large spectrum of diseases, including fertility disorders. Since mtDNA undergoes rather complex processes during gametogenesis and fertilization, clarification of the changes and functions of mtDNA and its essential impact on gamete quality and fertility during this process is of great significance. Thanks to the emergence and rapid development of gene editing technology, breakthroughs have been made in mitochondrial genome editing (MGE), offering great potential for the treatment of mtDNA-related diseases. In this review, we summarize the features of mitochondria and their unique genome, emphasizing their inheritance patterns; illustrate the role of mtDNA in gametogenesis and fertilization; and discuss potential therapies based on MGE as well as the outlook in this field.