Review Articles

Although oxidative stress is associated with a broad range of diseases, therapeutic antioxidant approaches have so far been disappointing. Here, Forman and Zhang review the roles of oxidative stress and redox signalling in disease, assess antioxidant therapeutic strategies and highlight key limitations that have challenged their clinical application.

PI3K signalling is one of the most frequently aberrantly activated pathways in cancer. However, the development of therapeutic PI3K pathway inhibitors has faced challenges including poor drug tolerance and drug resistance. Here, Vanhaesebroeck et al. review efforts to understand and therapeutically exploit the biology of PI3Kα and PI3Kδ — the key targets of currently approved PI3K inhibitors, highlighting lessons learned and future opportunities.

Zebrafish are useful model organisms for drug discovery, particularly in screening, disease modelling and toxicity assays. Here, Patton, Zon and Langenau discuss key recent successes in which zebrafish models have had key roles. Advances in gene modification technologies have enabled individual mutations to be recapitulated in zebrafish, leading to individualized treatments. Zebrafish xenografts as cancer models could also lead to rapid, personalized platforms for drug discovery.

Transcription factors have key roles in a variety of diseases, but they have been traditionally considered ‘undruggable’ by small-molecule ligands. Here, Henley and Koehler provide an overview of current understanding of transcription factor-mediated gene regulation, assess successful and emerging strategies to modulate transcription factor activity and address the associated challenges.

Twenty years have passed since the first small-molecule protein kinase inhibitor, imatinib, gained FDA approval. Here, Cohen et al. review advances in improving the potency and specificity of small-molecule protein kinase inhibitors and assess approaches to overcome the challenge of drug resistance. Applications of these compounds in cancers and other disorders, as well as future directions in the field, are discussed.

The contribution of inflammation to atherosclerosis is substantial, and is just beginning to be understood. In this Review, Soehnlein and Libby discuss how inflammation promotes atherosclerosis and its consequences, and how such processes could be targeted therapeutically. The potential pitfalls of targeting immune processes — namely the increased potential for infections — are also discussed, along with ways to modulate cardiovascular therapies in time and space to make them more effective.

Chimeric antigen receptors (CARs) have shown limited efficacy in the treatment of solid tumours. In this Review, Chen and colleagues discuss various engineering strategies to overcome the obstacles that the tumour microenvironment poses to CAR-T cells, to produce next-generation T cells with enhanced specificity and sustained function for the treatment of solid tumours.

This Review discusses how recent advances in understanding the activation of the innate immune system are shedding light on the immunological mechanisms of action of adjuvants and highlights how systems-based approaches are beginning to revitalize adjuvant design and development.

Antisense technology is now beginning to deliver on its promise to treat diseases by targeting RNA. Here, Crooke and colleagues describe the key technological advances that have enabled this progress and discuss recent clinical trials that illustrate the impact of these advances on the performance of antisense oligonucleotides in a wide range of therapeutic applications.

Protein arginine methyltransferases (PRMTs) regulate numerous biological processes, including transcription, splicing and the DNA damage response. In this article, Barsyte-Lovejoy and colleagues discuss the development of PRMT inhibitors, predominantly for cancer, and describe the challenges and potential new indications in which PRMT inhibition could be therapeutically relevant.

Gasdermins (GSDMs) are a recently characterized protein family that mediate a programmed inflammatory cell death termed pyroptosis. Here, Lieberman and colleagues review current understanding of the expression, activation and regulation of GSDMs, highlighting their roles in cell death, cytokine secretion and inflammation. Emerging opportunities to develop GSDM-targeted drugs and the associated challenges are highlighted.

Although checkpoint inhibitor blockade has been extremely successful in certain types of cancer, harnessing the immune system for immunosurveillance has met with numerous failures. In this Review, Mak and colleagues discuss the lessons learned from these failures, and how to incorporate the growing understanding of immuno-oncology into potential therapies, including combinations with existing checkpoint inhibitors.

The blood–brain barrier is a perennial challenge for the delivery of therapeutics to the central nervous system. In their Review, Terstappen and colleagues discuss non-invasive approaches to brain delivery, particularly for biopharmaceuticals, some of which are now in clinical testing.

Disregulation of circadian rhythms, as a result of jet lag or other lifestyle factors, can increase the risks of certain diseases. This Review analyses the different pathways involved in the regulation of the circadian clock and strategies that target the circadian systems.

Natural products have historically made a major contribution to pharmacotherapy, but also present challenges for drug discovery, such as technical barriers to screening, isolation, characterization and optimization. This Review discusses recent technological developments — including improved analytical tools, genome mining and engineering strategies, and microbial culturing advances — that are enabling a revitalization of natural product-based drug discovery.

Protein lysine methylation is an important post-translational modification of histone and non-histone proteins. In this Review, Gozani and colleagues discuss the role of protein lysine methyltransferases, the ‘writers’ of protein lysine methylation, in a range of diseases, and the progress and potential of targeting these enzymes therapeutically. They also consider the biology of lysine methyltransferases beyond epigenetic regulation as emerging targets for drug discovery.

Numerous proteins and lipids are covered in glycans, which affects the way these molecules interact. In this Review, Smith and Bertozzi discuss therapies targeting proteins that recognize glycosylation, namely the selectins and Siglecs, as well as glycan-targeted antibodies that have entered the clinic or are in development. They provide their perspectives on the future of glycobiology.

Image-based profiling is a strategy to mine the rich information in biological images. Carpenter and colleagues discuss how the application of machine learning is renewing interest in image-based profiling for all aspects of the drug discovery process, from understanding disease mechanisms to predicting a drug’s activity or mechanism of action.

Examining B cell depletion therapy (BCDT), an approved treatment for B cell malignancies, in autoimmune conditions has provided key insights into basic B cell biology. In this Review, Gommerman and colleagues discuss BCDT in autoimmune conditions, highlighting diseases in which BCDT has been clinically effective and the potential and pitfalls for BCDT in autoimmune conditions in which it has not yet been efficacious.

The Notch pathway plays multiple complex roles in cancer, exerting oncogenic or tumour-suppressive actions depending on the context. Here Miele and colleagues provide an overview of current understanding of the functions of Notch in cancer, highlighting key implications for the development of Notch-targeting therapeutics. Agents in clinical development and emerging therapeutic strategies are highlighted.