CRISPR-Cas9: A New Addition to the Drug Metabolism and Disposition Tool Box

Abstract

Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein 9 (Cas9), i.e., CRISPR-Cas9, has been extensively used as a gene-editing technology during recent years. Unlike earlier technologies for gene editing or gene knockdown, such as zinc finger nucleases and RNA interference, CRISPR-Cas9 is comparably easy to use, affordable, and versatile. Recently, CRISPR-Cas9 has been applied in studies of drug absorption, distribution, metabolism, and excretion (ADME) and for ADME model generation. To date, about 50 papers have been published describing in vitro or in vivo CRISPR-Cas9 gene editing of and-related genes. Twenty of these papers describe gene editing of clinically relevant genes, such as ATP-binding cassette drug transporters and cytochrome P450 drug-metabolizing enzymes. With CRISPR-Cas9, the ADME tool box has been substantially expanded. This new technology allows us to develop better and more predictive in vitro and in vivo ADME models and map previously underexplored genes and gene families. In this mini-review, we give an overview of the CRISPR-Cas9 technology and summarize recent applications of CRISPR-Cas9 within the ADME field. We also speculate about future applications of CRISPR-Cas9 in ADME research.

The Limitless Future of RNA Therapeutics

“…One of these molecules, called transactivating CRISPR RNA (tracrRNA), serves as a scaffold and binds to Cas9, a DNA endonuclease. The other molecule, called CRISPR RNA (crRNA), has sequence homology to the foreign DNA (Jiang and Doudna, 2017;Karlgren et al, 2018;Zhan et al, 2019) and ensures cleavage specificity. This native immune defense has been modified for genome editing.…”

“…NHEJ is an error-prone process that introduces small deletions or insertions (indels) and disrupts the targeted locus (gene knockout). HDR is a more precise process where a short donor DNA sequence is used for the double-stranded break repair (Jiang and Doudna, 2017;Karlgren et al, 2018), facilitating a gene knock-in.…”

Target Validation Using PROTACs: Applying the Four Pillars Framework

“…17 Unbiased functional genomic screening could be used to identify other transporters to help illuminate possible asymmetric tissue distribution in vivo and differences in degradation efficacy in different cell types and tissues. 38…”

Proteolysis targeting chimeras (PROTACs) are emerging therapeutics for hematologic malignancies

“…are still in their early developmental stage. TNAs also have several limitations including inefficient delivery to target cells, metabolic instability, and off-target effects that hinder their effective and safe use in vivo [ 1 , 34 , 35 ]. Some TNAs have been approved by the FDA for their use in different disease conditions, but none has been approved to treat cancers [ 36 , 37 ].…”