Long-term follow-up of cancer patients treated with gene therapy medicinal products

European Union requirements are discussed for the long-term follow-up of advanced therapy medicinal products, as well as how they can be applied to cancer patients treated with gene therapy medicinal products in the context of clinical trials, as described in a specific guideline issued by Gene Therapy Working Party at the European Medicine Agency.     

Stem cell-based cell therapy for neuroprotection in stroke: A review

Neurological disorders, such as stroke, are triggered by a loss of neurons and glial cells. Ischemic stroke remains a substantial problem for industrialized countries. Over the previous few decades our understanding about the pathophysiology of stroke has enhanced, nevertheless, more awareness is required to advance the field of stroke recovery. Existing therapies are incapable to adequately relief the disease outcome and are not appropriate to all patients. Meanwhile, the majority of patients continue to show neurological deficits even subsequent effective thrombolysis, recuperative therapies are immediately required that stimulate brain remodeling and repair once stroke damage has happened. Cell therapy is emergent as a hopeful new modality for increasing neurological recovery in ischemic stroke. Numerous types of stem cells from various sources have been identified and their possibility and efficiency for the treatment of stroke have been investigated. Stem cell therapy in patients with stroke using adult stem cells have been first practiced in clinical trials since 15 years ago. Even though stem cells have revealed a hopeful role in ischemic stroke in investigational studies besides early clinical pilot studies, cellular therapy in human is still at a primary stage. In this review, we summarize the types of stem cells, various delivery routes, and clinical application of stem cell-based therapy for stroke treatment.     

Advances and challenges in gene‐based approaches for osteoarthritis

Osteoarthritis (OA), a paramount cause of physical disability for which there is no definitive cure, is mainly characterized by the gradual loss of the articular cartilage. Current nonsurgical and reconstructive surgical therapies have not met success in reversing the OA phenotype so far. Gene transfer approaches allow for a long‐term and site‐specific presence of a therapeutic agent to re‐equilibrate the metabolic balance in OA cartilage and may consequently be suited to treat this slow and irreversible disorder. The distinct stages of OA need to be respected in individual gene therapy strategies. In this context, molecular therapy appears to be most effective for early OA. A critical step forward has been made by directly transferring candidate sequences into human articular chondrocytes embedded within their native extracellular matrix via recombinant adeno‐associated viral vectors. Although extensive studies in vitro attest to a growing interest in this approach, data from animal models of OA are sparse. A phase I dose‐escalating trial was recently performed in patients with advanced knee OA to examine the safety and activity of chondrocytes modified to produce the transforming growth factor β1 via intra‐articular injection, showing a dose‐dependent trend toward efficacy. Proof‐of‐concept studies in patients prior to undergoing total knee replacement may be privileged in the future to identify the best mode of translating this approach to clinical application, followed by randomized controlled trials. Copyright © 2013 John Wiley & Sons, Ltd.     

microRNAs: a new emerging class of players for disease diagnostics and gene therapy

microRNAs (miRNAs) are a new class of non-protein-coding small RNAs, which regulate the expression of more than 30% protein-coding genes. The unique expression profiles of different miRNAs in different types of cancers and at different stages in one cancer type suggest that miRNAs can function as novel biomarkers for disease diagnostics and may present a new strategy for miRNA gene therapy. Anti-miRNAs and antisense oligonucleotides (ASO) have been employed to inhibit specific miRNA expression in vitro and in vivo for investigational and clinical purposes. Although miRNA-based diagnostics and gene therapy are still in their infancy, their huge potentials will meet our need for future disease diagnostics and gene therapy. High efficient delivery of miRNAs into targeted sites, designing accurate anti-miRNA/ASOs, and related biosafety issues are three major challenges in this field.     

Gene therapy clinical trials worldwide to 2017: An update

To date, almost 2600 gene therapy clinical trials have been completed, are ongoing or have been approved worldwide. Our database brings together global information on gene therapy clinical activity from trial databases, official agency sources, published literature, conference presentations and posters kindly provided to us by individual investigators or trial sponsors. This review presents our analysis of clinical trials that, to the best of our knowledge, have been or are being performed worldwide. As of our November 2017 update, we have entries on 2597 trials undertaken in 38 countries. We have analysed the geographical distribution of trials, the disease indications (or other reasons) for trials, the proportions to which different vector types are used, and the genes that have been transferred. Details of the analyses presented, and our searchable database are available via The Journal of Gene Medicine Gene Therapy Clinical Trials Worldwide website at: http://www.wiley.co.uk/genmed/clinical . We also provide an overview of the progress being made in gene therapy clinical trials around the world, and discuss key trends since the previous review, namely the use of chimeric antigen receptor T cells for the treatment of cancer and advancements in genome editing technologies, which have the potential to transform the field moving forward.     

Gene therapy clinical trials worldwide to 2012 – an update

To date, over 1800 gene therapy clinical trials have been completed, are ongoing or have been approved worldwide. Our database brings together global information on gene therapy clinical trials from official agency sources, published literature, conference presentations and posters kindly provided to us by individual investigators or trial sponsors. This review presents our analysis of clinical trials that, to the best of our knowledge, have been or are being performed worldwide. As of our June 2012 update, we have entries on 1843 trials undertaken in 31 countries. We have analysed the geographical distribution of trials, the disease indications (or other reasons) for trials, the proportions to which different vector types are used, and which genes have been transferred. Details of the analyses presented, and our searchable database are available on The Journal of Gene Medicine Gene Therapy Clinical Trials Worldwide website at: http://www.wiley.co.uk/genmed/clinical . We also provide an overview of the progress being made in clinical trials of gene therapy approaches around the world and discuss the prospects for the future. Copyright © 2013 John Wiley & Sons, Ltd.     

Aerosol gene therapy

Gene therapy is a novel field of medicine that holds tremendous therapeutic potential for a variety of human diseases. Targeting of therapeutic gene delivery vectors to the lungs can be beneficial for treatment of various pulmonary diseases such as lung cancer, cystic fibrosis, pulmonary hypertension, alpha-1 antitrypsin deficiency, and asthma. Inhalation therapy using formulations delivered as aerosols targets the lungs through the pulmonary airways. The instant access and the high ratio of the drug deposited within the lungs noninvasively are the major advantages of aerosol delivery over other routes of administration. Delivery of gene formulations via aerosols is a relatively new field, which is less than a decade old. However, in this short period of time significant developments in aerosol delivery systems and vectors have resulted in major advances toward potential applications for various pulmonary diseases. This article will review these advances and the potential future applications of aerosol gene therapy technology.     

基因治疗研究中脂质体介导的基因转移技术

对于脂质体的深入研究特别是阳离子脂质体的研制使其逐步成为重要的基因转移载体之一,并且初步应用于基因治疗研究,同时多种靶向脂质体的研制也为体内靶向基因转移和表达奠定了基础。本文就脂质体的结构、功能、在基因治疗研究中的应用以及各种靶向脂质体的研制进行了介绍。     

基因治疗中外源基因的导入

基因治疗是将遗传物质导入靶细胞以达到治疗疾病的目的,目前基因治疗研究中的主要障碍是如何格外源基因导入靶细胞。本介绍基因治疗的原理和外源基因导入靶细胞时的常用方法,包括显微注射法、电穿孔法、基因枪粒子轰击法等。对基因治疗的现状、存在的问题及未来发展前景作了简要探讨。     

microRNA调控的靶向性病毒载体在基因治疗中的应用

安全、有效、具有靶向性的病毒载体是基因治疗药物在临床上得以应用的关键。microRNA是一类单链、内源性的转录后调控小分子,它的发现为开发具有靶向性调控能力的病毒载体提供了新的研究方法。以下在介绍microRNA调节病毒载体靶向性原理的基础上,着重介绍microRNA在清除复制能力病毒的污染、消除转基因特异性免疫、增强肿瘤靶向性基因治疗、开发活体疫苗等领域的应用。     

逆转录病毒载体在血友病A基因治疗中的研究进展

基因治疗是彻底治愈血友病A的最理想方法,逆转录病毒是最为常用的载体之一,本文对逆转录病毒在血友病A基因治疗中的研究进展作一综述。     

Porphyrias: Animal models and prospects for cellular and gene therapy

The rapid progress in the development of molecular technology has resulted in the identification of most of the genes of the heme biosynthesis pathway. Important problems in the pathogenesis and treatment of porphyrias now seem likely to be solved by the possibility of creating animal models and by the transfer of normal genes or cDNAs to target cells. Animal models of porphyrias naturally occur for erythropoietic protoporphyria and congenital erythropoietic porphyria, and different murine models have been or are being created for erythropoietic and hepatic porphyrias. The PBGD knock-out mouse will be useful for the understanding of nervous system dysfunction in acute porphyrias. Murine models of erythropoietic porphyrias are being used for bone-marrow transplantation experiments to study the features of erythropoietic and hepatic abnormalities. Gene transfer experiments have been startedin vitro to look at the feasibility of somatic gene therapy in erythropoietic porphyrias. In particular, we have documented sufficient gene transfer rate and metabolic correction in different CEP disease cells to indicate that this porphyria is a good candidate for treatment by gene therapy in hematopoietic stem cells. With the rapid advancement of methods that may allow more precise and/or efficient gene targeting, gene therapy will become a new therapeutic option for porphyrias.     

Predictive and therapeutic biomarkers in chimeric antigen receptor T-cell therapy: A clinical perspective

The adoptive transfer of genetically engineered T cells modified to express a chimeric antigen receptor (CAR) has shown remarkable activity and induces long-term remissions in patients with advanced hematologic malignancies. To date, little is known about predictive indicators of therapeutic efficacy or serious toxicity after CAR T-cell therapy in clinical practice. Biomarkers are not only potentially able to inform physicians and researchers of immunotherapy targets in particular but could also be used to monitor the effectiveness of treatments and to predict incidence of side effects in some circumstances. Identification of new biomarkers can therefore not only contribute to the development of new therapeutic and prognostic strategies for CAR T-cell therapy for cancer but also help to generate improved clinical practices for early recognition and minimization of adverse effects while preserving the antitumor activity of the CAR T cells. Herein, we will consider a variety of predictive and therapeutic biomarkers in CAR T-cell therapy and the state of current understanding of their clinical utility. The incorporation of biomarker studies in CAR T-cell clinical trials and practice will help to realize the potential clinical benefit of biomarker-guided therapy.     

Transduction of modified factor VIII gene improves lentiviral gene therapy efficacy for hemophilia A

Hemophilia A (HA) is a bleeding disorder caused by deficiency of the coagulation factor VIII (F8). F8 replacement is standard of care, whereas gene therapy (F8 gene) for HA is an attractive investigational approach. However, the large size of the F8 gene and the immunogenicity of the product present challenges in development of the F8 gene therapy. To resolve these problems, we synthesized a shortened F8 gene (F8-BDD) and cloned it into a lentiviral vector (LV). The F8-BDD produced mainly short cleaved inactive products in LV-transduced cells. To improve F8 functionality, we designed two novel F8-BDD genes, one with an insertion of eight specific N-glycosylation sites (F8-N8) and another which restored all N-glycosylation sites (F8-299) in the B domain. Although the overall protein expression was reduced, high coagulation activity (>100-fold) was detected in the supernatants of LV-F8-N8- and LV-F8-299-transduced cells. Protein analysis of F8 and the procoagulation cofactor, von Willebrand Factor, showed enhanced interaction after restoration of B domain glycosylation using F8-299. HA mouse hematopoietic stem cell transplantation studies illustrated that the bleeding phenotype was corrected after LV-F8-N8 or -299 gene transfer into the hematopoietic stem cells. Importantly, the F8-299 modification markedly reduced immunogenicity of the F8 protein in these HA mice. In conclusion, the modified F8-299 gene could be efficiently packaged into LV and, although with reduced expression, produced highly stable and functional F8 protein that corrected the bleeding phenotype without inhibitory immunogenicity. We anticipate that these results will be beneficial in the development of gene therapies against HA.     

Silencing of transgene expression in mammalian cells by DNA methylation and histone modifications in gene therapy perspective

DNA methylation and histone modifications are vital in maintaining genomic stability and modulating cellular functions in mammalian cells. These two epigenetic modifications are the most common gene regulatory systems known to spatially control gene expression. Transgene silencing by these two mechanisms is a major challenge to achieving effective gene therapy for many genetic conditions. The implications of transgene silencing caused by epigenetic modifications have been extensively studied and reported in numerous gene delivery studies. This review highlights instances of transgene silencing by DNA methylation and histone modification with specific focus on the role of these two epigenetic effects on the repression of transgene expression in mammalian cells from integrative and non-integrative based gene delivery systems in the context of gene therapy. It also discusses the prospects of achieving an effective and sustained transgene expression for future gene therapy applications.