In Vivo Ovarian Cancer Gene Therapy Using CRISPR-Cas9

Epigenetic-modifying agents: The potential game changers in the treatment of hematologic malignancies

Hematologic malignancies are lethal diseases arising from accumulated leukemic cells with substantial genetic or epigenetic defects in their natural development. Epigenetic modifications, including DNA methylation and histone modifications, are critical in hematologic malignancy formation, propagation, and treatment response. Both mutations and aberrant recruitment of epigenetic modifiers are reported in different hematologic malignancies, which regarding the reversible nature of epigenetic regulations, make them a potential target for cancer treatment. Here, we have first outlined a comprehensive overview of current knowledge related to epigenetic regulation's impact on the development and prognosis of hematologic malignancies. Furthermore, we have presented an updated overview regarding the current status of epigenetic-based drugs in hematologic malignancies treatment. And finally, discuss current challenges and ongoing clinical trials based on the manipulation of epigenetic modifies in hematologic malignancies.

Targeted Nanocarrier-Based Drug Delivery Strategies for Improving the Therapeutic Efficacy of PARP Inhibitors against Ovarian Cancer

The current focus of ovarian cancer (OC) research is the improvement of treatment options through maximising drug effectiveness. OC remains the fifth leading cause of cancer-induced mortality in women worldwide. In recent years, nanotechnology has revolutionised drug delivery systems. Nanoparticles may be utilised as carriers in gene therapy or to overcome the problem of drug resistance in tumours by limiting the number of free drugs in circulation and thereby minimising undesired adverse effects. Cell surface receptors, such as human epidermal growth factor 2 (HER2), folic acid (FA) receptors, CD44 (also referred to as homing cell adhesion molecule, HCAM), and vascular endothelial growth factor (VEGF) are highly expressed in ovarian cancer cells. Generation of active targeting nanoparticles involves modification with ligands that recognise cell surface receptors and thereby promote internalisation by cancer cells. Several poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) are currently used for the treatment of high-grade serous ovarian carcinomas (HGSOC) or platinum-sensitive relapsed OC. However, PARP resistance and poor drug bioavailability are common challenges, highlighting the urgent need to develop novel, effective strategies for ovarian cancer treatment. This review evaluates the utility of nanoparticles in ovarian cancer therapy, with a specific focus on targeted approaches and the use of PARPi nanocarriers to optimise treatment outcomes.

Revitalizing oral cancer research: Crispr-Cas9 technology the promise of genetic editing

This review presents an in-depth analysis of the immense potential of CRISPR-Cas9 technology in revolutionizing oral cancer research. It underscores the inherent limitations of conventional treatments while emphasizing the pressing need for groundbreaking approaches. The unparalleled capability of CRISPR-Cas9 to precisely target and modify specific genes involved in cancer progression heralds a new era in therapeutic intervention. Employing genome-wide CRISPR screens, vulnerabilities in oral cancer cells can be identified, thereby unravelling promising targets for therapeutic interventions. In the realm of oral cancer, the disruptive power of CRISPR-Cas9 manifests through its capacity to perturb genes that are intricately associated with drug resistance, consequently augmenting the efficacy of chemotherapy. To address the challenges that arise, this review diligently examines pertinent issues such as off-target effects, efficient delivery mechanisms, and the ethical considerations surrounding germline editing. Through precise gene editing, facilitated by CRISPR/Cas9, it becomes possible to overcome drug resistance by rectifying mutations, thereby enhancing the efficacy of personalized treatment strategies. This review delves into the prospects of CRISPR-Cas9, illuminating its potential applications in the domains of medicine, agriculture, and biotechnology. It is paramount to emphasize the necessity of ongoing research endeavors and the imperative to develop targeted therapies tailored specifically for oral cancer. By embracing this comprehensive overview, we can pave the way for ground-breaking treatments that instill renewed hope for enhanced outcomes in individuals afflicted by oral cancer.

Clinical applications of the CRISPR/Cas9 genome-editing system: Delivery options and challenges in precision medicine

CRISPR/Cas9 is an effective gene editing tool with broad applications for the prevention or treatment of numerous diseases. It depends on CRISPR (clustered regularly interspaced short palindromic repeats) as a bacterial immune system and plays as a gene editing tool. Due to the higher specificity and efficiency of CRISPR/Cas9 compared to other editing approaches, it has been broadly investigated to treat numerous hereditary and acquired illnesses, including cancers, hemolytic diseases, immunodeficiency disorders, cardiovascular diseases, visual maladies, neurodegenerative conditions, and a few X-linked disorders. CRISPR/Cas9 system has been used to treat cancers through a variety of approaches, with stable gene editing techniques. Here, the applications and clinical trials of CRISPR/Cas9 in various illnesses are described. Due to its high precision and efficiency, CRISPR/Cas9 strategies may treat gene-related illnesses by deleting, inserting, modifying, or blocking the expression of specific genes. The most challenging barrier to the in vivo use of CRISPR/Cas9 like off-target effects will be discussed. The use of transfection vehicles for CRISPR/Cas9, including viral vectors (such as an Adeno-associated virus (AAV)), and the development of non-viral vectors is also considered.

Natural Biopolymer-Based Delivery of CRISPR/Cas9 for Cancer Treatment

Over the last decade, the clustered, regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system has become the most promising gene editing tool and is broadly utilized to manipulate the gene for disease treatment, especially for cancer, which involves multiple genetic alterations. Typically, CRISPR/Cas9 machinery is delivered in one of three forms: DNA, mRNA, or ribonucleoprotein. However, the lack of efficient delivery systems for these macromolecules confined the clinical breakthrough of this technique. Therefore, a variety of nanomaterials have been fabricated to improve the stability and delivery efficiency of the CRISPR/Cas9 system. In this context, the natural biopolymer-based carrier is a particularly promising platform for CRISPR/Cas9 delivery due to its great stability, low toxicity, excellent biocompatibility, and biodegradability. Here, we focus on the advances of natural biopolymer-based materials for CRISPR/Cas9 delivery in the cancer field and discuss the challenges for their clinical translation.

Combining old and new concepts in targeting telomerase for cancer therapy: transient, immediate, complete and combinatory attack (TICCA)

Telomerase can overcome replicative senescence by elongation of telomeres but is also a specific element in most cancer cells. It is expressed more vastly than any other tumor marker. Telomerase as a tumor target inducing replicative immortality can be overcome by only one other mechanism: alternative lengthening of telomeres (ALT). This limits the probability to develop resistance to treatments. Moreover, telomerase inhibition offers some degree of specificity with a low risk of toxicity in normal cells. Nevertheless, only one telomerase antagonist reached late preclinical studies. The underlying causes, the pitfalls of telomerase-based therapies, and future chances based on recent technical advancements are summarized in this review. Based on new findings and approaches, we propose a concept how long-term survival in telomerase-based cancer therapies can be significantly improved: the TICCA (Transient Immediate Complete and Combinatory Attack) strategy.

Liposome-Based Carriers for CRISPR Genome Editing

The CRISPR-based genome editing technology, known as clustered regularly interspaced short palindromic repeats (CRISPR), has sparked renewed interest in gene therapy. This interest is accompanied by the development of single-guide RNAs (sgRNAs), which enable the introduction of desired genetic modifications at the targeted site when used alongside the CRISPR components. However, the efficient delivery of CRISPR/Cas remains a challenge. Successful gene editing relies on the development of a delivery strategy that can effectively deliver the CRISPR cargo to the target site. To overcome this obstacle, researchers have extensively explored non-viral, viral, and physical methods for targeted delivery of CRISPR/Cas9 and a guide RNA (gRNA) into cells and tissues. Among those methods, liposomes offer a promising approach to enhance the delivery of CRISPR/Cas and gRNA. Liposomes facilitate endosomal escape and leverage various stimuli such as light, pH, ultrasound, and environmental cues to provide both spatial and temporal control of cargo release. Thus, the combination of the CRISPR-based system with liposome delivery technology enables precise and efficient genetic modifications in cells and tissues. This approach has numerous applications in basic research, biotechnology, and therapeutic interventions. For instance, it can be employed to correct genetic mutations associated with inherited diseases and other disorders or to modify immune cells to enhance their disease-fighting capabilities. In summary, liposome-based CRISPR genome editing provides a valuable tool for achieving precise and efficient genetic modifications. This review discusses future directions and opportunities to further advance this rapidly evolving field.

Synthetic nanoparticles for the delivery of CRISPR/Cas9 gene editing system: classification and biomedical applications

Gene editing has great potential in biomedical research including disease diagnosis and treatment. Clustered regularly interspaced short palindromic repeats (CRISPR) is the most straightforward and cost-effective method. The efficient and precise delivery of CRISPR can impact the specificity and efficacy of gene editing. In recent years, synthetic nanoparticles have been discovered as effective CRISPR/Cas9 delivery vehicles. We categorized synthetic nanoparticles for CRISPR/Cas9 delivery and discribed their advantages and disadvantages. Further, the building blocks of different kinds of nanoparticles and their applications in cells/tissues, cancer and other diseases were described in detail. Finally, the challenges encountered in the clinical application of CRISPR/Cas9 delivery materials were discussed, and potential solutions were provided regarding efficiency and biosafety issues.

CRISPR/Cas9 Genome Editing for Tissue-Specific In Vivo Targeting: Nanomaterials and Translational Perspective

Clustered randomly interspaced short palindromic repeats (CRISPRs) and its associated endonuclease protein, i.e., Cas9, have been discovered as an immune system in bacteria and archaea; nevertheless, they are now being adopted as mainstream biotechnological/molecular scissors that can modulate ample genetic and nongenetic diseases via insertion/deletion, epigenome editing, messenger RNA editing, CRISPR interference, etc. Many Food and Drug Administration-approved and ongoing clinical trials on CRISPR adopt ex vivo strategies, wherein the gene editing is performed ex vivo, followed by reimplantation to the patients. However, the in vivo delivery of the CRISPR components is still under preclinical surveillance. This review has summarized the nonviral nanodelivery strategies for gene editing using CRISPR/Cas9 and its recent advancements, strategic points of view, challenges, and future aspects for tissue-specific in vivo delivery of CRISPR/Cas9 components using nanomaterials.

CRISPR/Cas9-based gene-editing technology for sickle cell disease

Sickle cell disease (SCD) is the most common monogenic hematologic disorder and is essentially congenital hemolytic anemia caused by an inherited point mutation in the β-globin on chromosome 11. Although the genetic basis of SCD was revealed as early as 1957, treatment options for SCD have been very limited to date. Hematopoietic stem cell transplantation (HSCT) was thought to hold promise as a cure for SCD, but the available donors were still only 15% useful. Gene therapy has advanced rapidly into the 21st century with the promise of a cure for SCD, and gene editing strategies based on the cluster-based regularly interspaced short palindromic repeat sequence (CRISPR)/Cas9 system have revolutionized the field of gene therapy by precisely targeting genes. In this paper, we review the pathogenesis and therapeutic approaches of SCD, briefly summarize the delivery strategies of CRISPR/Cas9, and finally discuss in depth the current status, application barriers, and solution directions of CRISPR/Cas9 in SCD. Through the review in this paper, we hope to provide some references for gene therapy in SCD.

Design of Folate-Containing Liposomal Nucleic Acid Delivery Systems for Antitumor Therapy

The delivery of therapeutic nucleic acids is a prospective method for the treatment of both inherited and acquired diseases including cancer. To achieve maximal delivery efficiency and selectivity, nucleic acids should be targeted to the cells of interest. In the case of cancer, such targeting may be provided through folate receptors overexpressed in many tumor cells. For this purpose, folic acid and its lipoconjugates are used. Compared to other targeting ligands, folic acid provides low immunogenicity, rapid tumor penetration, high affinity to a wide range of tumors, chemical stability, and easy production. Different delivery systems can utilize targeting by folate ligand including liposomal forms of anticancer drugs, viruses, and lipid and polymer nanoparticles. This review focuses on the liposomal gene delivery systems that provide targeted nucleic acid transport into tumor cells due to folate lipoconjugates. Moreover, important development step, such as rational design of lipoconjugates, folic acid content, size, and ζ-potential of lipoplexes are discussed.

Recent Advance of Liposome Nanoparticles for Nucleic Acid Therapy

Gene therapy, as an emerging therapeutic approach, has shown remarkable advantages in the treatment of some major diseases. With the deepening of genomics research, people have gradually realized that the emergence and development of many diseases are related to genetic abnormalities. Therefore, nucleic acid drugs are gradually becoming a new boon in the treatment of diseases (especially tumors and genetic diseases). It is conservatively estimated that the global market of nucleic acid drugs will exceed $20 billion by 2025. They are simple in design, mature in synthesis, and have good biocompatibility. However, the shortcomings of nucleic acid, such as poor stability, low bioavailability, and poor targeting, greatly limit the clinical application of nucleic acid. Liposome nanoparticles can wrap nucleic acid drugs in internal cavities, increase the stability of nucleic acid and prolong blood circulation time, thus improving the transfection efficiency. This review focuses on the recent advances and potential applications of liposome nanoparticles modified with nucleic acid drugs (DNA, RNA, and ASO) and different chemical molecules (peptides, polymers, dendrimers, fluorescent molecules, magnetic nanoparticles, and receptor targeting molecules). The ability of liposome nanoparticles to deliver nucleic acid drugs is also discussed in detail. We hope that this review will help researchers design safer and more efficient liposome nanoparticles, and accelerate the application of nucleic acid drugs in gene therapy.

Current updates of CRISPR/Cas9-mediated genome editing and targeting within tumor cells: an innovative strategy of cancer management

Clustered regularly interspaced short palindromic repeats-associated protein (CRISPR/Cas9), an adaptive microbial immune system, has been exploited as a robust, accurate, efficient and programmable method for genome targeting and editing. This innovative and revolutionary technique can play a significant role in animal modeling, in vivo genome therapy, engineered cell therapy, cancer diagnosis and treatment. The CRISPR/Cas9 endonuclease system targets a specific genomic locus by single guide RNA (sgRNA), forming a heteroduplex with target DNA. The Streptococcus pyogenes Cas9/sgRNA:DNA complex reveals a bilobed architecture with target recognition and nuclease lobes. CRISPR/Cas9 assembly can be hijacked, and its nanoformulation can be engineered as a delivery system for different clinical utilizations. However, the efficient and safe delivery of the CRISPR/Cas9 system to target tissues and cancer cells is very challenging, limiting its clinical utilization. Viral delivery strategies of this system may have many advantages, but disadvantages such as immune system stimulation, tumor promotion risk and small insertion size outweigh these advantages. Thus, there is a desperate need to develop an efficient non-viral physical delivery system based on simple nanoformulations. The delivery strategies of CRISPR/Cas9 by a nanoparticle-based system have shown tremendous potential, such as easy and large-scale production, combination therapy, large insertion size and efficient in vivo applications. This review aims to provide in-depth updates on Streptococcus pyogenic CRISPR/Cas9 structure and its mechanistic understanding. In addition, the advances in its nanoformulation-based delivery systems, including lipid-based, polymeric structures and rigid NPs coupled to special ligands such as aptamers, TAT peptides and cell-penetrating peptides, are discussed. Furthermore, the clinical applications in different cancers, clinical trials and future prospects of CRISPR/Cas9 delivery and genome targeting are also discussed.

Progress of delivery methods for CRISPR-Cas9

INTRODUCTION

Gene therapy is becoming increasingly common in clinical practice, giving hope for the correction of a wide range of human diseases and defects. The CRISPR/Cas9 system, consisting of the Cas9 nuclease and single-guide RNA (sgRNA), has revolutionized the field of gene editing. However, efficiently delivering the CRISPR-Cas9 to the target organ or cell remains a significant challenge. In recent years, with rapid advances in nanoscience, materials science, and medicine, researchers have developed various technologies that can deliver CRISPR-Cas9 in different forms for in vitro and in vivo gene editing. Here, we review the development of the CRISPR-Cas9 and describe the delivery forms and the vectors that have emerged in CRISPR-Cas9 delivery, summarizing the key barriers and the promising strategies that vectors currently face in delivering the CRISPR-Cas9.

AREAS COVERED

With the rapid development of CRISPR-Cas9, delivery methods are becoming increasingly important in the in vivo delivery of CRISPR-Cas9.

EXPERT OPINION

CRISPR-Cas9 is becoming increasingly common in clinical trials. However, the complex nuclease and protease environment is a tremendous challenge for in vivo clinical applications. Therefore, the development of delivery methods is highly likely to take the application of CRISPR-Cas9 technology to another level.

Gene Therapy for Malignant and Benign Gynaecological Disorders: A Systematic Review of an Emerging Success Story

Simple Summary

This review discusses all the major advances in gene therapy of gynaecological disorders, highlighting the novel and potentially therapeutic perspectives associated with such an approach. It specifically focuses on the gene therapy strategies against major gynaecological malignant disorders, such as ovarian, cervical, and endometrial cancer, as well as benign disorders, such as uterine leiomyomas, endometriosis, placental, and embryo implantation disorders. The above therapeutic strategies, which employ both viral and non-viral systems for mutation compensation, suicide gene therapy, oncolytic virotherapy, antiangiogenesis and immunopotentiation approaches, have yielded promising results over the last decade, setting the grounds for successful clinical trials.

Abstract

Despite the major advances in screening and therapeutic approaches, gynaecological malignancies still present as a leading cause of death among women of reproductive age. Cervical cancer, although largely preventable through vaccination and regular screening, remains the fourth most common and most lethal cancer type in women, while the available treatment schemes still pose a fertility threat. Ovarian cancer is associated with high morbidity rates, primarily due to lack of symptoms and high relapse rates following treatment, whereas endometrial cancer, although usually curable by surgery, it still represents a therapeutic problem. On the other hand, benign abnormalities, such as fibroids, endometriosis, placental, and embryo implantation disorders, although not life-threatening, significantly affect women’s life and fertility and have high socio-economic impacts. In the last decade, targeted gene therapy approaches toward both malignant and benign gynaecological abnormalities have led to promising results, setting the ground for successful clinical trials. The above therapeutic strategies employ both viral and non-viral systems for mutation compensation, suicide gene therapy, oncolytic virotherapy, antiangiogenesis and immunopotentiation. This review discusses all the major advances in gene therapy of gynaecological disorders and highlights the novel and potentially therapeutic perspectives associated with such an approach.

Pre-clinical non-viral vectors exploited for in vivo CRISPR/Cas9 gene editing: an overview

Clustered regulatory interspaced short palindromic repeats or CRISPR/Cas9 has emerged as a potent and versatile tool for efficient genome editing. This technology has been exploited for several applications including disease modelling, cell therapy, diagnosis, and treatment of many diseases including cancer. The in vivo application of CRISPR/Cas9 is hindered by poor stability, pharmacokinetic profile, and the limited ability of the CRISPR payloads to cross biological barriers. Although viral vectors have been implemented as delivery tools for efficient in vivo gene editing, their application is associated with high immunogenicity and toxicity, limiting their clinical translation. Hence, there is a need to explore new delivery methods that can guarantee safe and efficient delivery of the CRISPR/Cas9 components to target cells. In this review, we first provide a brief history and principles of nuclease-mediated gene editing, we then focus on the different CRISPR/Cas9 formats outlining their potentials and limitations. Finally, we discuss the alternative non-viral delivery strategies currently adopted for in vivo CRISPR/Cas9 gene editing.

CRISPR based therapeutics: a new paradigm in cancer precision medicine

Background

Clustered regularly interspaced short palindromic repeat (CRISPR)-CRISPR-associated protein (Cas) systems are the latest addition to the plethora of gene-editing tools. These systems have been repurposed from their natural counterparts by means of both guide RNA and Cas nuclease engineering. These RNA-guided systems offer greater programmability and multiplexing capacity than previous generation gene editing tools based on zinc finger nucleases and transcription activator like effector nucleases. CRISPR-Cas systems show great promise for individualization of cancer precision medicine.

Main body

The biology of Cas nucleases and dead Cas based systems relevant for in vivo gene therapy applications has been discussed. The CRISPR knockout, CRISPR activation and CRISPR interference based genetic screens which offer opportunity to assess functions of thousands of genes in massively parallel assays have been also highlighted. Single and combinatorial gene knockout screens lead to identification of drug targets and synthetic lethal genetic interactions across different cancer phenotypes. There are different viral and non-viral (nanoformulation based) modalities that can carry CRISPR-Cas components to different target organs in vivo.

Conclusion

The latest developments in the field in terms of optimization of performance of the CRISPR-Cas elements should fuel greater application of the latter in the realm of precision medicine. Lastly, how the already available knowledge can help in furtherance of use of CRISPR based tools in personalized medicine has been discussed.

Nanoparticles-mediated CRISPR/Cas gene editing delivery system

The CRISPR/Cas gene editing system utilizes CRISPR RNA to guide the endonuclease in specifically breaking target gene, and then repairs genomic DNA by the means of homology directed repair (HDR) and non-homologous end joining (NHEJ). The gene editing system can only play its role in gene editing when it enters the nucleus. This crucial step in the process of gene editing is the major hurdle to gene therapy as it is still a huge challenge to efficiently deliver the CRISPR/Cas system to target tissues and cells. The low delivery efficiency hinders the clinical transformation of this technology. At present, delivery systems mainly include physical methods, viral vectors, and non-viral vectors. Due to the advantages of nanomaterial, it is currently being used rapidly in developing non-viral delivery systems. This review focuses on the mechanism of CRISPR/Cas and the delivery of gene editing system, following the research progress of nanoparticle-mediated gene editing.

Non-Viral Vectors for Delivery of Nucleic Acid Therapies for Cancer

The research and development of non-viral gene therapy has been extensive over the past decade and has received a big push thanks to the recent successful approval of non-viral nucleic acid therapy products. Despite these developments, nucleic acid therapy applications in cancer have been limited. One of the main causes of this has been the imbalance in development of delivery vectors as compared with sophisticated nucleic acid payloads, such as siRNA, mRNA, etc. This paper reviews non-viral vectors that can be used to deliver nucleic acids for cancer treatment. It discusses various types of vectors and highlights their current applications. Additionally, it discusses a perspective on the current regulatory landscape to facilitate the commercial translation of gene therapy.

CRISPR/Cas9: A Molecular Tool for Ovarian Cancer Management beyond Gene Editing

Ovarian cancer manifests with early metastases and has an adverse outcome, impacting the health of women globally. Currently, this malignancy is often treated with cytoreductive surgery and platinum-based chemotherapy. This treatment option has a limited success rate due to tumor recurrence and chemoresistance. Consequently, the fundamental objective of ovarian cancer treatment is the development of novel treatment approaches. As a new robust tool, the CRISPR/Cas9 gene-editing system has shown immense promise in elucidating the molecular basis of all the facets of ovarian cancer. Due to the precise gene editing capabilities of CRISPR-Cas9, researchers have been able to conduct a more comprehensive investigation of the genesis of ovarian cancer. This gained knowledge can be translated into the development of novel diagnostic approaches and newer therapeutic targets for this dreadful malignancy. There is encouraging preclinical evidence that suggests that CRISPR/Cas9 is a powerful versatile tool for selectively targeting cancer cells and inhibiting tumor growth, establishing new signaling pathways involved in carcinogenesis, and verifying biomolecules as druggable targets. In this review, we analyzed the current research and progress made using CRISPR/Cas9-based engineering strategies in the diagnosis and treatment, as well as the challenges in bringing this method to clinics. This comprehensive analysis will lay the basis for subsequent research in the future for the treatment of ovarian cancer.

The power and the promise of CRISPR/Cas9 genome editing for clinical application with gene therapy

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Due to its high accuracy and efficiency, CRISPR/Cas9 techniques may provide a great chance to treat some gene-related diseases.

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Researchers used the CRISPR/Cas9 technique to cure or alleviate cancers through different approaches, such as gene therapy and immune therapy.

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The treatment of ocular diseases by Cas9 has entered into clinical phases.

Background

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is derived from the bacterial innate immune system and engineered as a robust gene-editing tool. Due to the higher specificity and efficiency of CRISPR/Cas9, it has been widely applied to many genetic and non-genetic disease, including cancers, genetic hemolytic diseases, acquired immunodeficiency syndrome, cardiovascular diseases, ocular diseases, and neurodegenerative diseases, and some X-linked diseases. Furthermore, in terms of the therapeutic strategy of cancers, many researchers used the CRISPR/Cas9 technique to cure or alleviate cancers through different approaches, such as gene therapy and immune therapy.

Aim of Review

Here, we conclude the recent application and clinical trials of CRISPR/Cas9 in non-cancerous diseases and cancers and pointed out some of the problems to be solved.

Key Scientific Concepts of Review

CRISPR/Cas9, derived from the microbial innate immune system, is developed as a robust gene-editing tool and has been applied widely. Due to its high accuracy and efficiency, CRISPR/Cas9 techniques may provide a great chance to treat some gene-related diseases by disrupting, inserting, correcting, replacing, or blocking genes for clinical application with gene therapy.

Optimizing sgRNA to Improve CRISPR/Cas9 Knockout Efficiency: Special Focus on Human and Animal Cell

During recent years, clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) technologies have been noticed as a rapidly evolving tool to deliver a possibility for modifying target sequence expression and function. The CRISPR/Cas9 tool is currently being used to treat a myriad of human disorders, ranging from genetic diseases and infections to cancers. Preliminary reports have shown that CRISPR technology could result in valued consequences for the treatment of Duchenne muscular dystrophy (DMD), cystic fibrosis (CF), β-thalassemia, Huntington's diseases (HD), etc. Nonetheless, high rates of off-target effects may hinder its application in clinics. Thereby, recent studies have focused on the finding of the novel strategies to ameliorate these off-target effects and thereby lead to a high rate of fidelity and accuracy in human, animals, prokaryotes, and also plants. Meanwhile, there is clear evidence indicating that the design of the specific sgRNA with high efficiency is of paramount importance. Correspondingly, elucidation of the principal parameters that contributed to determining the sgRNA efficiencies is a prerequisite. Herein, we will deliver an overview regarding the therapeutic application of CRISPR technology to treat human disorders. More importantly, we will discuss the potent influential parameters (e.g., sgRNA structure and feature) implicated in affecting the sgRNA efficacy in CRISPR/Cas9 technology, with special concentration on human and animal studies.

Trends and Frontiers of Research on Cancer Gene Therapy From 2016 to 2020: A Bibliometric Analysis

Background: With rapid development in molecular biology techniques and a greater understanding of cancer pathogenesis, the growing attention has been concentrated on cancer gene therapy, with numerous articles on this topic published in recent 5 years. However, there is lacking a bibliometric analysis of research on cancer gene therapy. Therefore, the aim of the present study was to conduct a bibliometric analysis to provide the trends and frontiers of research on cancer gene therapy during 2016-2020. Methods: We utilized CiteSpace 5.7.R5 software to conduct a bibliometric analysis of publications on cancer gene therapy published during 2016-2020. The bibliometric records were obtained from the Web of Science Core Collection. Results: A total of 4,392 papers were included in the bibliometric analysis. Materials Science and Nanoscience and Nanotechnology took an increasing part in the field of cancer gene therapy. Additionally, WANG W was the most productive author, while ZHANG Y ranked top in terms of citations. Harvard Medical School and Sichuan University ranked top in the active institutions. P NATL ACAD SCI USA was identified as the core journal in the field of cancer gene therapy. "Ovarian cancer" was found to be the latest keyword with the strongest burst. The keyword analysis suggested that the top three latest clusters were labeled "gene delivery," "drug delivery," and "gene therapy." In the reference analysis, cluster#2 labeled "gene delivery" held a dominant place considering both the node volume and mean year. Conclusion: The academic attention on cancer gene therapy was growing at a dramatically high speed. Materials Science and Nanoscience and Nanotechnology might become promising impetus for the development of this field. "Gene delivery" was thought to best reflect the research frontier on cancer gene therapy. The top-cited articles on gene delivery were focused on several novel non-viral vectors due to their specialty compared with viral vectors. "Ovarian cancer" was likely to be the potential research direction. These findings would help medical workers conduct further investigations on cancer gene therapy.

The pH-Dependent Controlled Release of Encapsulated Vitamin B1 from Liposomal Nanocarrier

In this work, we firstly presented a simple encapsulation method to prepare thiamine hydrochloride (vitamin B1)-loaded asolectin-based liposomes with average hydrodynamic diameter of ca. 225 and 245 nm under physiological and acidic conditions, respectively. In addition to the optimization of the sonication and magnetic stirring times used for size regulation, the effect of the concentrations of both asolectin carrier and initial vitamin B1 on the entrapment efficiency (EE %) was also investigated. Thermoanalytical measurements clearly demonstrated that after the successful encapsulation, only weak interactions were discovered between the carriers and the drug molecules. Moreover, the dissolution profiles under physiological (pH = 7.40) and gastric conditions (pH = 1.50) were also registered and the release profiles of our liposomal B1 system were compared with the dissolution profile of the pure drug solution and a manufactured tablet containing thiamin hydrochloride as active ingredient. The release curves were evaluated by nonlinear fitting of six different kinetic models. The best goodness of fit, where the correlation coefficients in the case of all three systems were larger than 0.98, was reached by application of the well-known second-order kinetic model. Based on the evaluation, it was estimated that our liposomal nanocarrier system shows 4.5-fold and 1.5-fold larger drug retention compared to the unpackaged vitamin B1 under physiological conditions and in artificial gastric juice, respectively.

Nanotechnology-based delivery of CRISPR/Cas9 for cancer treatment

CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats-associated protein 9) is a potent technology for gene-editing. Owing to its high specificity and efficiency, CRISPR/Cas9 is extensity used for human diseases treatment, especially for cancer, which involves multiple genetic alterations. Different concepts of cancer treatment by CRISPR/Cas9 are established. However, significant challenges remain for its clinical applications. The greatest challenge for CRISPR/Cas9 therapy is how to safely and efficiently deliver it to target sites in vivo. Nanotechnology has greatly contributed to cancer drug delivery. Here, we present the action mechanisms of CRISPR/Cas9, its application in cancer therapy and especially focus on the nanotechnology-based delivery of CRISPR/Cas9 for cancer gene editing and immunotherapy to pave the way for its clinical translation. We detail the difficult barriers for CRISIR/Cas9 delivery in vivo and discuss the relative solutions for encapsulation, target delivery, controlled release, cellular internalization, and endosomal escape.

CRISPR-Cas systems for genome editing of mammalian cells

In the past decade, ZFNs and TALENs have been used for targeted genome engineering and have gained scientific attention. It has demonstrated huge potential for gene knockout, knock-in, and indels in desired locations of genomes to understand molecular mechanism of diseases and also discover therapy. However, both the genome engineering techniques are still suffering from design, screening and validation in cell and higher organisms. CRISPR-Cas9 is a rapid, simple, specific, and versatile technology and it has been applied in many organisms including mammalian cells. CRISPR-Cas9 has been used for animal models to modify animal cells for understanding human disease for novel drug discovery and therapy. Additionally, base editing has also been discussed herewith for conversion of C/G-to-T/A or A/T-to-G/C without DNA cleavage or donor DNA templates for correcting mutations or altering gene functions. In this chapter, we highlight CRISPR-Cas9 and base editing for desired genome editing in mammalian cells for a better understanding of molecular mechanisms, and biotechnological and therapeutic applications.

Genome-editing approaches and applications: a brief review on CRISPR technology and its role in cancer

The development of genome-editing technologies in 1970s has discerned a new beginning in the field of science. Out of different genome-editing approaches such as Zing-finger nucleases, TALENs, and meganucleases, clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 (CRISPR/Cas9) is a recent and versatile technology that has the ability of making changes to the genome of different organisms with high specificity. Cancer is a complex process that is characterized by multiple genetic and epigenetic changes resulting in abnormal cell growth and proliferation. As cancer is one of the leading causes of deaths worldwide, a large number of studies are done to understand the molecular mechanisms underlying the development of cancer. Because of its high efficiency and specificity, CRISPR/Cas9 has emerged as a novel and powerful tool in the field of cancer research. CRISPR/Cas9 has the potential to accelerate cancer research by dissecting tumorigenesis process, generating animal and cellular models, and identify drug targets for chemotherapeutic approaches. However, despite having tremendous potential, there are certain challenges associated with CRISPR/Cas9 such as safe delivery to the target, potential off-target effects and its efficacy which needs to be addressed prior to its clinical application. In this review, we give a gist of different genome-editing technologies with a special focus on CRISPR/Cas9 development, its mechanism of action and its applications, especially in different type of cancers. We also highlight the importance of CRISPR/Cas9 in generating animal models of different cancers. Finally, we present an overview of the clinical trials and discuss the challenges associated with translating CRISPR/Cas9 in clinical use.

Recent trends in cancer therapy: A review on the current state of gene delivery

Cancer treatment has been always considered one of the most critical and vital themes of clinical issues. Many approaches have been developed, depending on the type and the stage of tumor. Gene therapy has the potential to revolutionize different cancer therapy. With the advent of recent bioinformatics technologies and genetic science, it become possible to identify, diagnose and determine the potential treatment using the technology of gene delivery. Several approaches have been developed and experimented in vitro and vivo for cancer therapy including: naked nucleic acids based therapy, targeting micro RNAs, oncolytic virotherapy, suicide gene based therapy, targeting telomerase, cell mediated gene therapy, and CRISPR/Cas9 based therapy. In this review, we present a straightforward introduction to cancer biology and occurrence, highlighting different viral and non-viral gene delivery systems for gene therapy and critically discussed the current and various strategies for cancer gene therapy.

Delivery of CRISPR/Cas systems for cancer gene therapy and immunotherapy

The clustered, regularly interspaced, short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) systems are efficient and versatile gene editing tools, which offer enormous potential to treat cancer by editing genome, transcriptome or epigenome of tumor cells and/or immune cells. A large body of works have been done with CRISPR/Cas systems for genetic modification, and 16 clinical trials were conducted to treat cancer by ex vivo or in vivo gene editing approaches. Now, promising preclinical works have begun using CRISPR/Cas systems in vivo. However, efficient and safe delivery of CRISPR/Cas systems in vivo is still a critical challenge for their clinical applications. This article summarizes delivery of CRISPR/Cas systems by physical methods, viral vectors and non-viral vectors for cancer gene therapy and immunotherapy. The prospects for the development of physical methods, viral vectors and non-viral vectors for delivery of CRISPR/Cas systems are reviewed, and promising advances in cancer treatment using CRISPR/Cas systems are discussed.

Rational designs of in vivo CRISPR-Cas delivery systems

The CRISPR-Cas system initiated a revolution in genome editing when it was, for the first time, demonstrated success in the mammalian cells. Today, scientists are able to readily edit genomes, regulate gene transcription, engineer posttranscriptional events, and image nucleic acids using CRISPR-Cas-based tools. However, to efficiently transport CRISPR-Cas into target tissues/cells remains challenging due to many extra- and intra-cellular barriers, therefore largely limiting the applications of CRISPR-based therapeutics in vivo. In this review, we summarize the features of plasmid-, RNA- and ribonucleoprotein (RNP)-based CRISPR-Cas therapeutics. Then, we survey the current in vivo delivery systems. We specify the requirements for efficient in vivo delivery in clinical settings, and highlight both efficiency and safety for different CRISPR-Cas tools.

Role of non-coding RNAs in modulating the response of cancer cells to paclitaxel treatment

Paclitaxel is a chemotherapeutic substance that is administered for treatment of an extensive spectrum of human malignancies. In spite of its potent short-term effects against tumor cells, resistance to paclitaxel occurs in a number of patients precluding its long-term application in these patients. Non-coding RNAs have been shown to influence response of cancer cells to this chemotherapeutic agent via different mechanisms. Mechanistically, these transcripts regulate expression of several genes particularly those being involved in the apoptotic processes. Lots of in vivo and in vitro assays have demonstrated the efficacy of oligonucleotide-mediated microRNAs (miRNA)/ long non-coding RNAs (lncRNA) silencing in enhancement of response of cancer cells to paclitaxel. Therefore, targeted therapies against non-coding RNAs have been suggested as applicable modalities for combatting resistance to this agent. In the present review, we provide a summary of studies which assessed the role of miRNAs and lncRNAs in conferring resistance to paclitaxel.

Nanovesicle-Mediated Delivery Systems for CRISPR/Cas Genome Editing

Genome-editing technology has emerged as a potential tool for treating incurable diseases for which few therapeutic modalities are available. In particular, discovery of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system together with the design of single-guide RNAs (sgRNAs) has sparked medical applications of genome editing. Despite the great promise of the CRISPR/Cas system, its clinical application is limited, in large part, by the lack of adequate delivery technology. To overcome this limitation, researchers have investigated various systems, including viral and nonviral vectors, for delivery of CRISPR/Cas and sgRNA into cells. Among nonviral delivery systems that have been studied are nanovesicles based on lipids, polymers, peptides, and extracellular vesicles. These nanovesicles have been designed to increase the delivery of CRISPR/Cas and sgRNA through endosome escape or using various stimuli such as light, pH, and environmental features. This review covers the latest research trends in nonviral, nanovesicle-based delivery systems that are being applied to genome-editing technology and suggests directions for future progress.

CRISPR-mediated modification of DNA methylation pattern in the new era of cancer therapy

In the last 2 decades, a wide variety of studies have been conducted on epigenetics and its role in various cancers. A major mechanism of epigenetic regulation is DNA methylation, including aberrant DNA methylation variations such as hypermethylation and hypomethylation in the promoters of critical genes, which are commonly detected in tumors and mark the early stages of cancer development. Therefore, epigenetic therapy has been of special importance in the last decade for cancer treatment. In epigenetic therapy, all efforts are made to modulate gene expression to the normal status. Importantly, recent studies have shown that epigenetic therapy is focusing on the new gene editing technology, CRISPR-Cas9. This tool was found to be able to effectively modulate gene expression and alter almost any sequence in the genome of cells, resulting in events such as a change in acetylation, methylation, or histone modifications. Of note, the CRISPR-Cas9 system can be used for the treatment of cancers caused by epigenetic alterations. The CRISPR-Cas9 system has greater advantages than other available methods, including potent activity, easy design and high velocity as well as the ability to target any DNA or RNA site. In this review, we described epigenetic modulators, which can be used in the CRISPR-Cas9 system, as well as their functions in gene expression alterations that lead to cancer initiation and progression. In addition, we surveyed various species of CRISPR-dead Cas9 (dCas9) systems, a mutant version of Cas9 with no endonuclease activity. Such systems are applicable in epigenetic therapy for gene expression modulation through chemical group editing on nucleosomes and chromatin remodeling, which finally return the cell to the normal status and prevent cancer progression.

Development of Therapeutic Vaccines for Ovarian Cancer

Ovarian cancer remains the deadliest of all gynecologic malignancies. Our expanding knowledge of ovarian cancer immunology has allowed the development of therapies that generate systemic anti-tumor immune responses. Current immunotherapeutic strategies include immune checkpoint blockade, cellular therapies, and cancer vaccines. Vaccine-based therapies are designed to induce both adaptive and innate immune responses directed against ovarian cancer associated antigens. Tumor-specific effector cells, in particular cytotoxic T cells, are activated to recognize and eliminate ovarian cancer cells. Vaccines for ovarian cancer have been studied in various clinical trials over the last three decades. Despite evidence of vaccine-induced humoral and cellular immune responses, the majority of vaccines have not shown significant anti-tumor efficacy. Recently, improved vaccine development using dendritic cells or synthetic platforms for antigen presentation have shown promising clinical benefits in patients with ovarian cancer. In this review, we provide an overview of therapeutic vaccine development in ovarian cancer, discuss proposed mechanisms of action, and summarize the current clinical experience.

Harnessing the potential of CRISPR-based platforms to advance the field of hospital medicine

INTRODUCTION

Clustered regularly interspaced short palindromic repeats (CRISPR) are segments of nucleic acid that play a role in prokaryotic defense and form the basis of a genome editing technology that allows permanent alteration of genetic material. This methodology, known as CRISPR-Cas9, is poised to revolutionize molecular biology, but no literature yet exists on how these advances will affect hospitalists.

AREAS COVERED

These specialists in inpatient medicine care for a wide variety of hospitalized patients, including those with infectious disease, cancer, cardiovascular disease, autoimmune disease, hematologic disease, and a variety of other conditions that may soon be impacted by advances in gene-modifying technology provided by CRISPR-Cas9. A Literature search was performed using PubMed [1 December 2019-17 April 2020].

EXPERT OPINION

This paper reviews the remarkable diagnostic and therapeutic potential of the CRISPR-Cas9 platform and concludes with a look at ethical issues and technical hurdles pertaining to the implementation of permanent gene modification in the practice of Hospital Medicine.

Novel zwitterionic vectors: Multi-functional delivery systems for therapeutic genes and drugs

Zwitterions consist of equal molar cationic and anionic moieties and thus exhibit overall electroneutrality. Zwitterionic materials include phosphorylcholine, sulfobetaine, carboxybetaine, zwitterionic amino acids/peptides, and other mix-charged zwitterions that could form dense and stable hydration shells through the strong ion-dipole interaction among water molecules and zwitterions. As a result of their remarkable hydration capability and low interfacial energy, zwitterionic materials have become ideal choices for designing therapeutic vectors to prevent undesired biosorption especially nonspecific biomacromolecules during circulation, which was termed antifouling capability. And along with their great biocompatibility, low cytotoxicity, negligible immunogenicity, systematic stability and long circulation time, zwitterionic materials have been widely utilized for the delivery of drugs and therapeutic genes. In this review, we first summarized the possible antifouling mechanism of zwitterions briefly, and separately introduced the features and advantages of each type of zwitterionic materials. Then we highlighted their applications in stimuli-responsive "intelligent" drug delivery systems as well as tumor-targeting carriers and stressed the multifunctional role they played in therapeutic gene delivery.

The Impact of CRISPR-Cas9 on Age-related Disorders: From Pathology to Therapy

With advances in medical technology, the number of people over the age of 60 is on the rise, and thus, increasing the prevalence of age-related pathologies within the aging population. Neurodegenerative disorders, cancers, metabolic and inflammatory diseases are some of the most prevalent age-related pathologies affecting the growing population. It is imperative that a new treatment to combat these pathologies be developed. Although, still in its infancy, the CRISPR-Cas9 system has become a potent gene-editing tool capable of correcting gene-mediated age-related pathology, and therefore ameliorating or eliminating disease symptoms. Deleting target genes using the CRISPR-Cas9 system or correcting for gene mutations may ameliorate many different neurodegenerative disorders detected in the aging population. Cancer cells targeted by the CRISPR-Cas9 system may result in an increased sensitivity to chemotherapeutics, lower proliferation, and higher cancer cell death. Finally, reducing gene targeting inflammatory molecules production through microRNA knockout holds promise as a therapeutic strategy for both arthritis and inflammation. Here we present a review based on how the expanding world of genome editing can be applied to disorders and diseases affecting the aging population.

Progress and challenges towards CRISPR/Cas clinical translation

CRISPR/Cas systems (clustered regularly interspaced short palindromic repeats) have emerged as powerful tools to manipulate the genome for both research and therapeutic purposes. However, the clinical use of this system is hindered by multiple challenges, such as the rate of off-target effects, editing efficiency, the efficacy of HDR, immunogenicity, as well as development of efficient and safe delivery vehicles that can carry these compounds. Tremendous efforts are being conducted to overcome these challenges, including the discovery and engineering of more precise and efficacious Cas nucleases. Moreover, in recent years multiple viral and non-viral delivery approaches have been explored for in vivo delivery of CRISPR components. Here, we summarize the available CRISPR/Cas toolbox for genome editing as well as the recently developed in vivo delivery vehicles for CRISPR/Cas system. Furthermore, we discuss the remaining challenges for successful clinical translation of this system and highlight the current clinical applications.

Current RNA-based Therapeutics in Clinical Trials

Long-term research on various types of RNAs has led to further understanding of diverse mechanisms, which eventually resulted in the rapid development of RNA-based therapeutics as powerful tools in clinical disease treatment. Some of the developing RNA drugs obey the antisense mechanisms including antisense oligonucleotides, small interfering RNAs, microRNAs, small activating RNAs, and ribozymes. These types of RNAs could be utilized to inhibit/activate gene expression or change splicing to provide functional proteins. In the meantime, some others based on different mechanisms like modified messenger RNAs could replace the dysfunctional endogenous genes to manage some genetic diseases, and aptamers with special three-dimensional structures could bind to specific targets in a high-affinity manner. In addition, the recent most popular CRISPR-Cas technology, consisting of a crucial single guide RNA, could edit DNA directly to generate therapeutic effects. The desired results from recent clinical trials indicated the great potential of RNA-based drugs in the treatment of various diseases, but further studies on improving delivery materials and RNA modifications are required for the novel RNA-based drugs to translate to the clinic. This review focused on the advances and clinical studies of current RNA-based therapeutics, analyzed their challenges and prospects.

Appropriate Delivery of the CRISPR/Cas9 System through the Nonlysosomal Route: Application for Therapeutic Gene Editing

The development of gene delivery has attracted increasing attention, especially when the introduction and application of the CRISPR/Cas9 gene editing system appears promising for gene therapy. However, ensuring biosafety and high gene editing efficiency at the same time poses a great challenge for its in vivo applications. Herein, a pardaxin peptide (PAR)-modified cationic liposome (PAR-Lipo) is developed. The results are indicative that significantly enhanced gene editing efficiency can be obtained through the mediation of PAR-Lipos compared to non-Lipos (non-PAR-modified liposomes) and Lipofectamine 2000, owing to its protection toward carried nucleotide by the prevention of lysosomal capture, prolongation of retention time in cells through the accumulation in the endoplasmic reticulum (ER), and more importantly, facilitation of the nuclear access via an ER-nucleus route. Accumulation of PAR-Lipos in the ER may improve the binding of Cas9 and sgRNA, thus further contributing to the eventually enhanced gene editing efficiency. Given their high biosafety, PAR-Lipos are used to mediate the knockout of the oncogene CDC6 in vivo, which results in significant tumor growth inhibition. This work may provide a useful reference for enhancing the delivery of gene editing systems, thus improving the potential for their future clinical applications.

Mitigating off-target effects in CRISPR/Cas9-mediated in vivo gene editing

The rapid advancement of genome editing technologies has opened up new possibilities in the field of medicine. Nuclease-based techniques such as the CRISPR/Cas9 system are now used to target genetically linked disorders that were previously hard-to-treat. The CRISPR/Cas9 gene editing approach wields several advantages over its contemporary editing systems, notably in the ease of component design, implementation and the option of multiplex genome editing. While results from the early phase clinical trials have been encouraging, the small patient population recruited into these trials hinders a conclusive assessment on the safety aspects of the CRISPR/Cas9 therapy. Potential safety concerns include the lack of fidelity in the CRISPR/Cas9 system which may lead to unintended DNA modifications at non-targeted gene loci. This review focuses modifications to the CRISPR/Cas9 components that can mitigate off-target effects in in vitro and preclinical models and its translatability to gene therapy in patient populations.

Therapeutic applications of CRISPR/Cas9 in breast cancer and delivery potential of gold nanomaterials

Globally, approximately 1 in 4 cancers in women are diagnosed as breast cancer (BC). Despite significant advances in the diagnosis and therapy BCs, many patients develop metastases or relapses. Hence, novel therapeutic strategies are required, that can selectively and efficiently kill malignant cells. Direct targeting of the genetic and epigenetic aberrations that occur in BC development is a promising strategy to overcome the limitations of current therapies, which target the tumour phenotype. The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas system, composed of only an easily modifiable single guide RNA (sgRNA) sequence bound to a Cas9 nuclease, has revolutionised genome editing due to its simplicity and efficiency compared to earlier systems. CRISPR/Cas9 and its associated catalytically inactivated dCas9 variants facilitate the knockout of overexpressed genes, correction of mutations in inactivated genes, and reprogramming of the epigenetic landscape to impair BC growth. To achieve efficient genome editing in vivo, a vector is required to deliver the components to target cells. Gold nanomaterials, including gold nanoparticles and nanoclusters, display many advantageous characteristics that have facilitated their widespread use in theranostics, as delivery vehicles, and imaging and photothermal agents. This review highlights the therapeutic applications of CRISPR/Cas9 in treating BCs, and briefly describes gold nanomaterials and their potential in CRISPR/Cas9 delivery.

Advances in delivery vectors for gene therapy in liver cancer

Hepatocellular carcinoma (HCC) is the third most common cause of cancer death globally, mainly due to lack of effective treatments – a problem that gene therapy is poised to solve. Successful gene therapy requires safe and efficient delivery vectors, and recent advances in both viral and nonviral vectors have made an important impact on HCC gene therapy delivery. This review explores how adenoviral, retroviral and adeno-associated viral vectors have been modified to increase safety and delivery capacity, highlighting studies and clinical trials using these vectors for HCC gene therapy. Nanoparticles, liposomes, exosomes and virosomes are also featured in their roles as HCC gene delivery vectors. Finally, new discoveries in gene editing technology and their impacts on HCC gene therapy are discussed.

Non-viral delivery of CRISPR/Cas9 complex using CRISPR-GPS nanocomplexes

There is a critical need for the development of safe and efficient delivery technologies for CRISPR/Cas9 to advance translation of genome editing to the clinic. Non-viral methods that are simple, efficient, and completely based on biologically-derived materials could offer such potential. Here we report a simple and modular tandem peptide-based nanocomplex system with cell-targeting capacity that efficiently combines guide RNA (sgRNA) with Cas9 protein, and facilitates internalization of sgRNA/Cas9 ribonucleoprotein complexes to yield robust genome editing across multiple cell lines.

Formulation Strategies for Folate-Targeted Liposomes and Their Biomedical Applications

The folate receptor (FR) is a tumor-associated antigen that can bind with folic acid (FA) and its conjugates with high affinity and ingests the bound molecules inside the cell via the endocytic mechanism. A wide variety of payloads can be delivered to FR-overexpressed cells using folate as the ligand, ranging from small drug molecules to large DNA-containing macromolecules. A broad range of folate attached liposomes have been proven to be highly effective as the targeted delivery system. For the rational design of folate-targeted liposomes, an intense conceptual understanding combining chemical and biomedical points of view is necessary because of the interdisciplinary nature of the field. The fabrication of the folate-conjugated liposomes basically involves the attachment of FA with phospholipids, cholesterol or peptides before liposomal formulation. The present review aims to provide detailed information about the design and fabrication of folate-conjugated liposomes using FA attached uncleavable/cleavable phospholipids, cholesterol or peptides. Advances in the area of folate-targeted liposomes and their biomedical applications have also been discussed.

Biomaterials as vectors for the delivery of CRISPR-Cas9

The emergence of the CRISPR-Cas9 gene editing system has brought much hope and excitement to the field of gene therapy and the larger scientific community. However, in order for CRISPR-based therapies to be translated to the clinical setting, there is an urgent need to develop optimized vectors for their delivery. The delivery vector is a crucial determinant of the therapeutic efficacy of gene editing and should be designed to accommodate various factors including the form of the payload, the physiological environment, and the potential immune responses. Recently, biomaterials have become an attractive option for the delivery of Cas9 due to their tunability, biocompatibility and increasing efficacy at drug delivery. Biomaterials offer a unique solution for creating tailored vectors to meet the demands of various applications that cannot be easily met by other delivery methods. In this review, we will discuss the various biomaterial systems that have been used to deliver Cas9 in its plasmid, mRNA and protein forms. In addition, the functions of these materials will be reviewed to understand their roles in Cas9 delivery. Finally, the immune challenges associated with Cas9 and the delivery materials will be discussed as an understanding of the immune responses along with the functions of biomaterials will ultimately guide the field in designing new delivery systems for the clinical applications of CRISPR-Cas9.

Applications of Genome Editing Technology in Animal Disease Modeling and Gene Therapy

Genome editing technology is a technique for targeted genetic modifications, enabling the knockout and addition of specific DNA fragments. This technology has been widely used in various types of biomedical research, clinics and agriculture. In terms of disease research, constructing appropriate animal models is necessary. Combining reproductive technology with genome editing, many animal disease models have been generated for basic and clinical research. In addition, precisely targeted modifications allow genome editing to flourish in the field of gene therapy. Many mutations refractory to traditional gene therapy could be permanently corrected at the DNA level. Thus, genome editing is undoubtedly a promising technology for gene therapy. In this review, we mainly introduce the applications of genome editing in constructing animal disease models and gene therapies, as well as its future prospects and challenges.

Optimization of the Linker Length of Mannose-Cholesterol Conjugates for Enhanced mRNA Delivery to Dendritic Cells by Liposomes

Liposomes (LPs) as commonly used mRNA delivery systems remain to be rationally designed and optimized to ameliorate the antigen expression of mRNA vaccine in dendritic cells (DCs). In this study, we synthesized mannose-cholesterol conjugates (MP_n-CHs) by click reaction using different PEG units (PEG₁₀₀, PEG₁₀₀₀, and PEG₂₀₀₀) as linker molecules. MP_n-CHs were fully characterized and subsequently used to prepare DC-targeting liposomes (MP_n-LPs) by a thin-film dispersion method. MP_n-LPs loaded with mRNA (MP_n-LPX) were finally prepared by a simple self-assembly method. MP_n-LPX displayed bigger diameter (about 135 nm) and lower zeta potential (about 40 mV) compared to MP_n-LPs. The in vitro transfection experiment on DC2.4 cells demonstrated that the PEG length of mannose derivatives had significant effect on the expression of GFP-encoding mRNA. MP₁₀₀₀-LPX containing MP₁₀₀₀-CH can achieve the highest transfection efficiency (52.09 ± 4.85%), which was significantly superior to the commercial transfection reagent Lipo 3K (11.47 ± 2.31%). The optimal DC-targeting MP₁₀₀₀-LPX showed an average size of 132.93 ± 4.93 nm and zeta potential of 37.93 ± 2.95 mV with nearly spherical shape. Moreover, MP₁₀₀₀-LPX can protect mRNA against degradation in serum with high efficacy. The uptake study indicated that MP₁₀₀₀-LPX enhanced mRNA expression mainly through the over-expressing mannose receptor (CD206) on the surface of DCs. In conclusion, mannose modified LPs might be a potential DC-targeting delivery system for mRNA vaccine after rational design and deserve further study on the in vivo delivery profile and anti-tumor efficacy.