Abstract
The off-target toxicity of drugs targeted to proteins imparts substantial health and economic costs. Proteome interaction studies can reveal off-target effects with unintended proteins; however, little attention has been paid to intracellular RNAs as potential off-targets that may contribute to toxicity. To begin to assess this, we developed a reactivity-based RNA profiling methodology and applied it to uncover transcriptome interactions of a set of Food and Drug Administration-approved small-molecule drugs in vivo. We show that these protein-targeted drugs pervasively interact with the human transcriptome and can exert unintended biological effects on RNA functions. In addition, we show that many off-target interactions occur at RNA loci associated with protein binding and structural changes, allowing us to generate hypotheses to infer the biological consequences of RNA off-target binding. The results suggest that rigorous characterization of drugs’ transcriptome interactions may help assess target specificity and potentially avoid toxicity and clinical failures.

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Data availability
All sequencing data are available through the Gene Expression Omnibus (GEO) under accession GSE229331. Data supporting the findings of this study are available in the Article, and its Supplementary Information and Supplementary Tables. Source data and bedgraphs of RBRP scores are also freely available at figshare at https://doi.org/10.6084/m9.figshare.20326824. Source data are provided with this paper.
Code availability
The RBRP scripts used for bioinformatics analysis are freely available at https://github.com/linglanfang/RBRP.
References
Lin, A. et al. Off-target toxicity is a common mechanism of action of cancer drugs undergoing clinical trials. Sci. Transl. Med. 11, eaaw8412 (2019).
Onakpoya, I. J., Heneghan, C. J. & Aronson, J. K. Post-marketing withdrawal of 462 medicinal products because of adverse drug reactions: a systematic review of the world literature. BMC Med 14, 10 (2016).
Harrison, R. K. Phase II and phase III failures: 2013–2015. Nat Rev Drug Discov 15, 817–818 (2016).
Morgan, B. S. et al. R-BIND: an interactive database for exploring and developing RNA-targeted chemical probes. ACS Chem. Biol. 14, 2691–2700 (2019).
Donlic, A. et al. R-BIND 2.0: an updated database of bioactive RNA-targeting small molecules and associated RNA secondary structures. ACS Chem. Biol. 17, 1556–1566 (2022).
Zhang, P. et al. Reprogramming of protein-targeted small-molecule medicines to RNA by ribonuclease recruitment. J. Am. Chem. Soc. 143, 13044–13055 (2021).
Velagapudi, S. P. et al. Approved anti-cancer drugs target oncogenic non-coding RNAs. Cell Chem. Biol. 25, 1086–1094 (2018).
Disney, M. D. Targeting RNA with small molecules to capture opportunities at the intersection of chemistry, biology, and medicine. J. Am. Chem. Soc. 141, 6776–6790 (2019).
Kim, S. Exploring chemical information in PubChem. Curr Protoc 1, e217 (2021).
Suresh, B. M. et al. A general fragment-based approach to identify and optimize bioactive ligands targeting RNA. Proc. Natl Acad. Sci. USA 117, 33197–33203 (2020).
Balaratnam, S. et al. A chemical probe based on the PreQ1 metabolite enables transcriptome-wide mapping of binding sites. Nat. Commun. 12, 5856 (2021).
Mukherjee, H. et al. PEARL-seq: a photoaffinity platform for the analysis of small molecule–RNA interactions. ACS Chem. Biol. 15, 2374–2381 (2020).
Velagapudi, S. P., Li, Y. & Disney, M. D. A cross-linking approach to map small molecule-RNA binding sites in cells. Bioorg. Med. Chem. Lett. 29, 1532–1536 (2019).
Rzuczek, S. G. et al. Precise small-molecule recognition of a toxic CUG RNA repeat expansion. Nat. Chem. Biol. 13, 188–193 (2017).
Regulski, E. E. & Breaker, R. R. In-line probing analysis of riboswitches. Methods Mol. Biol. 419, 53–67 (2008).
Zeller, M. J. et al. SHAPE-enabled fragment-based ligand discovery for RNA. Proc. Natl Acad. Sci. USA 119, e2122660119 (2022).
Tong, Y. et al. Transcriptome-wide mapping of small-molecule RNA-binding sites in cells informs an isoform-specific degrader of QSOX1 mRNA. J. Am. Chem. Soc. 144, 11620–11625 (2022).
Chang, M. T. et al. Identifying transcriptional programs underlying cancer drug response with TraCe-seq. Nat. Biotechnol. 40, 86–93 (2022).
Wurtmann, E. J. & Wolin, S. L. RNA under attack: cellular handling of RNA damage. Crit. Rev. Biochem. Mol. Biol. 44, 34–49 (2009).
Qiu, Z., Lu, L., Jian, X. & He, C. A diazirine-based nucleoside analogue for efficient DNA interstrand photocross-linking. J. Am. Chem. Soc. 130, 14398–14399 (2008).
Nakamoto, K. & Ueno, Y. Diazirine-containing RNA photo-cross-linking probes for capturing microRNA targets. J. Org. Chem. 79, 2463–2472 (2014).
Di Antonio, M., McLuckie, K. I. & Balasubramanian, S. Reprogramming the mechanism of action of chlorambucil by coupling to a G-quadruplex ligand. J. Am. Chem. Soc. 136, 5860–5863 (2014).
Spitale, R. C. et al. Structural imprints in vivo decode RNA regulatory mechanisms. Nature 519, 486–490 (2015).
Marchant, J. When antibiotics turn toxic. Nature 555, 431–433 (2018).
von Baum, H., Bottcher, S., Abel, R., Gerner, H. J. & Sonntag, H. G. Tissue and serum concentrations of levofloxacin in orthopaedic patients. Int. J. Antimicrob. Agents 18, 335–340 (2001).
Flynn, R. A. et al. Transcriptome-wide interrogation of RNA secondary structure in living cells with icSHAPE. Nat. Protoc. 11, 273–290 (2016).
Herrmann, C. J. et al. PolyASite 2.0: a consolidated atlas of polyadenylation sites from 3′ end sequencing. Nucleic Acids Res. 48, D174–D179 (2020).
Balaratnam, S. et al. A chemical probe based on the PreQ(1) metabolite enables transcriptome-wide mapping of binding sites. Nat. Commun. 12, 5856 (2021).
Wang, J., Schultz, P. G. & Johnson, K. A. Mechanistic studies of a small-molecule modulator of SMN2 splicing. Proc. Natl Acad. Sci. USA 115, E4604–E4612 (2018).
Shahsavarinia, K. et al. An umbrella review of clinical efficacy and adverse cardiac events associated with hydroxychloroquine or chloroquine with or without azithromycin in patients with COVID-19. Anesth Pain Med 11, e115827 (2021).
Begley, C. G. et al. Drug repurposing: misconceptions, challenges, and opportunities for academic researchers. Sci. Transl. Med. 13, eabd5524 (2021).
Kolli, A. R., Calvino-Martin, F. & Hoeng, J. Translational modeling of chloroquine and hydroxychloroquine dosimetry in human airways for treating viral respiratory infections. Pharm. Res. 39, 57–73 (2022).
Force, T. & Kolaja, K. L. Cardiotoxicity of kinase inhibitors: the prediction and translation of preclinical models to clinical outcomes. Nat. Rev. Drug Discov. 10, 111–126 (2011).
Padroni, G., Patwardhan, N. N., Schapira, M. & Hargrove, A. E. Systematic analysis of the interactions driving small molecule-RNA recognition. RSC Med. Chem. 11, 802–813 (2020).
Guo, P. et al. Compound shape effects in minor groove binding affinity and specificity for mixed sequence DNA. J. Am. Chem. Soc. 140, 14761–14769 (2018).
Yazdani, K. et al. Machine learning informs RNA-binding chemical space. Angew. Chem. Int. Ed. 62, e202211358 (2023).
Cai, Z., Zafferani, M., Akande, O. M. & Hargrove, A. E. Quantitative structure–activity relationship (QSAR) study predicts small-molecule binding to RNA structure. J. Med. Chem. 65, 7262–7277 (2022).
Van Nostrand, E. L. et al. A large-scale binding and functional map of human RNA-binding proteins. Nature 583, 711–719 (2020).
Yang, Y. C. et al. CLIPdb: a CLIP-seq database for protein–RNA interactions. BMC Genomics 16, 51 (2015).
Khoshnevis, S., Dreggors-Walker, R. E., Marchand, V., Motorin, Y. & Ghalei, H. Ribosomal RNA 2′-O-methylations regulate translation by impacting ribosome dynamics. Proc. Natl Acad. Sci. USA 119, e2117334119 (2022).
Jansson, M. D. et al. Regulation of translation by site-specific ribosomal RNA methylation. Nat. Struct. Mol. Biol. 28, 889–899 (2021).
Sun, L. et al. RNA structure maps across mammalian cellular compartments. Nat. Struct. Mol. Biol. 26, 322–330 (2019).
Mustoe, A. M. et al. Pervasive regulatory functions of mRNA structure revealed by high-resolution SHAPE probing. Cell 173, 181–195 (2018).
Mortimer, S. A., Kidwell, M. A. & Doudna, J. A. Insights into RNA structure and function from genome-wide studies. Nat. Rev. Genet. 15, 469–479 (2014).
Yeung, P. Y. et al. Systematic evaluation and optimization of the experimental steps in RNA G-quadruplex structure sequencing. Sci Rep. 9, 8091 (2019).
Yu, H., Qi, Y., Yang, B., Yang, X. & Ding, Y. G4Atlas: a comprehensive transcriptome-wide G-quadruplex database. Nucleic Acids Res. 51, D126–D134 (2023).
Xu, H. & Hurley, L. H. A first-in-class clinical G-quadruplex-targeting drug. The bench-to-bedside translation of the fluoroquinolone QQ58 to CX-5461 (Pidnarulex). Bioorg. Med. Chem. Lett. 77, 129016 (2022).
Tang, C. F. & Shafer, R. H. Engineering the quadruplex fold: nucleoside conformation determines both folding topology and molecularity in guanine quadruplexes. J. Am. Chem. Soc. 128, 5966–5973 (2006).
Balaratnam, S. et al. Investigating the NRAS 5' UTR as a target for small molecules. Cell Chem. Biol. 30, 643–657 (2023).
Fay, M. M., Lyons, S. M. & Ivanov, P. RNA G-quadruplexes in biology: principles and molecular mechanisms. J. Mol. Biol. 429, 2127–2147 (2017).
Wacker, S. A., Houghtaling, B. R., Elemento, O. & Kapoor, T. M. Using transcriptome sequencing to identify mechanisms of drug action and resistance. Nat. Chem. Biol. 8, 235–237 (2012).
Kumari, S., Bugaut, A., Huppert, J. L. & Balasubramanian, S. An RNA G-quadruplex in the 5′ UTR of the NRAS proto-oncogene modulates translation. Nat. Chem. Biol. 3, 218–221 (2007).
Pottel, J. et al. The activities of drug inactive ingredients on biological targets. Science 369, 403–413 (2020).
Mullard, A. Parsing clinical success rates. Nat. Rev. Drug Discov. 15, 447 (2016).
Morgan, B. S., Forte, J. E., Culver, R. N., Zhang, Y. & Hargrove, A. E. Discovery of key physicochemical, structural, and spatial properties of RNA-targeted bioactive ligands. Angew. Chem. Int. Ed. 56, 13498–13502 (2017).
Vicens, Q. & Westhof, E. RNA as a drug target: the case of aminoglycosides. ChemBioChem 4, 1018–1023 (2003).
Van Norman, G. A. Limitations of animal studies for predicting toxicity in clinical trials: is it time to rethink our current approach? JACC Basic Transl. Sci. 4, 845–854 (2019).
Corsello, S. M. et al. The drug repurposing hub: a next-generation drug library and information resource. Nat. Med. 23, 405–408 (2017).
Backman, T. W., Cao, Y. & Girke, T. ChemMine tools: an online service for analyzing and clustering small molecules. Nucleic Acids Res. 39, W486–W491 (2011).
Warren, L. et al. Highly efficient reprogramming to pluripotency and directed differentiation of human cells with synthetic modified mRNA. Cell Stem Cell 7, 618–630 (2010).
Dong, Z. W. et al. RTL-P: a sensitive approach for detecting sites of 2′-O-methylation in RNA molecules. Nucleic Acids Res. 40, e157 (2012).
Acknowledgements
We acknowledge support from the US National Institutes of Health (GM130704 and GM145357 to E.T.K.) for this work. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. We thank A. E. Hargrove, A. Đonlić and E. G. Swanson at Duke University for sharing the list of FDA-approved drugs. We thank T. McLaughlin at Vincent Coates Foundation Mass Spectrometry Laboratory, Stanford University Mass Spectrometry (RRID:SCR_017801) for acquiring the HRMS data. We thank S. Lynch for his help with NMR studies. We thank staff at the Stanford PAN facility for support with oligo synthesis. This work was also supported in part by NIH P30 CA124435 utilizing the Stanford Cancer Institute Proteomics/Mass Spectrometry Shared Resource and NIH High End Instrumentation grant (1 S10 OD028697-01).
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Contributions
E.T.K. conceived the project and supervised the work. E.T.K. and L.F. designed experiments. L.F. performed experiments and data analysis. L.F. developed codes and the bioinformatics pipeline. Y.L. synthesized the acylating probe of dasatinib. L.X. performed the in vitro translation and SHAPE experiments. W.A.V., M.G.M. and A.M.K. conducted the groundwork. L.F. and E.T.K. wrote the manuscript, with input from all authors.
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Extended data
Extended Data Fig. 1 RBRP workflow and experimental setup.
Library 1: Cells were treated with the drug-conjugated acylating probe. RBRP workflow identifies RBRP signals from drug-promoted acylation, random site acylation, and non-specific binding events during biotin-mediated pulldown. Library 2: Cells were treated with DMSO. RBRP workflow identifies RBRP signals from non-specific binding events. Library 3: Cells were treated with drug-conjugated acylating probe and the unmodified drug. RBRP workflow identifies RBRP signals from random site acylation, non-specific binding events during biotin-mediated pulldown, and changes in transcript abundance. Library 4: Cells were treated with excess unmodified drugs. RBRP workflow identifies RBRP signals from non-specific binding events during biotin-mediated pulldown and changes in transcript abundance. Library 5: Cells were treated with Linker-AI. RBRP workflow identifies RBRP signals from random site acylation and non-specific binding events during biotin-mediated pulldown.
Extended Data Fig. 2 RNA-seq determines how excess unmodified drug influences transcripts abundance in HEK293 cells.
a, Workflow of RNA-seq with HEK293 cells treated with unmodified drugs or DMSO. b-d, Volcano plot showing effects of unmodified Lev (b), HCQ (c), and Das (d) on transcript abundance. X-axis: log-transformed ratio of transcript abundance in the presence over the absence of unmodified drug. Y-axis: the negative value of log-transformed P-value calculated with DESeq2 using a two-tailed Wald test. Fold-change=transcript abudance (drug-treated)/transcript abudance (DMSO).
Extended Data Fig. 3 Transcript abundance and RT-stop frequencies are strongly concordant between RBRP sequencing libraries from two biological replicates.
a-c, Scatter plot showing very strong correlation of transcript expression value (RPKM) between two biological replicates (Pearson correlation r = 1.00) in HEK293 cells treated with Lev-AI only (a), Lev-AI and excess unmodified Lev (b), and DMSO (c). d-f, The concordance of RT-stop frequencies is high for most transcripts of read depth higher than the optimized cut-off value (200) in sequencing libraries of Lev-AI only (d), Lev-AI and excess unmodified Lev (e), and DMSO (f).
Extended Data Fig. 4 qPCR independently validates the transcriptome interactions of Levofloxacin (Lev) at 15 transcriptome binding sites in HEK293 cells.
Workflow showing the strategies of validating competable 2´-OH acylation sites with qPCR (Top panel). qPCR validated and quantified the relative level of 2´-OH acylation at the drug-binding loci. Data represent mean ± s.e.m., n = 3 biologically independent experiments. Statistical significance was calculated with two-tailed unpaired Student’s t-tests: *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. P values are 0.0227 (FAM71F2), 0.0007 (EEF2), <0.0001 (RPL5), 0.0346 (RNU1-88P), 0.0015 (H3F3B), 0.0023 (ARPC3), 0.0009 (YBX1), 0.0019 (SIAE), 0.0478 (RAN), 0.0006 (NME1), <0.0001 (ILF2), 0.0055 (XR_934306.3), 0.0051 (SIK3), 0.0140 (FTL), and 0.0103 (SNORD110).
Extended Data Fig. 5 RBRP complements the existing diazirine-based profiling method.
a, Chemical structure of diazirine-conjugated analogue of Levofloxacin (Lev-diazirine). The drug moiety is coloured blue, “click” handle” is coloured red, and diazirine moiety is coloured brown. b, Workflow for profiling RNA targets of Lev with Lev-diazirine probe. c, Volcano plot showing transcripts that are confidently enriched by Lev-diazirine in HEK293 cells. d, Volcano plot showing shared RNA targets that are identified by both Lev-AI and Lev-diazirine. X-axis: log-transformed ratio of transcript abundance in the presence over the absence of unmodified drug. Y-axis: the negative value of log-transformed P-value calculated with DESeq2. d, Venn diagram comparing RNA targets that were identified by Lev-AI and Lev-diazirine. e. Volcano plot showing shared transcripts (“hits”) identified by both RBRP and the existing diazirine-based profiling method. Transcripts that were enriched by Lev-diazirine are coloured grey. Shared transcripts that were identified by both Lev-AI and Lev-diazirine are coloured red. For c and e, X-axis: log-transformed ratio of transcript abundance in the presence over the absence of unmodified drug. Y-axis: the negative value of log-transformed P-value calculated with DESeq2 using a two-tailed Wald test. Fold-change=transcript abudance (Lev-diazirine-treated)/transcript abudance (Lev-diazirine + Competitor). f, Floating bar graphs comparing the distribution of RT stops of Lev-AI and Lev-diazirine towards four nucleotides. The floating bars represent the range of all data points (minimum to maximum). Lines represent the mean values. Data points are collected from two biologically independent sequencing experiments. All data points for nucleotide in each experiment are compiled for data analysis. Lev-diazirine: n = 22,958 (A), 19,154 (U), 19,375 (C), and 18,992 (G). Lev-diazirine + Competitor: n = 2,420 (A), 1,778 (U), 2,160 (C), and 1,895 (G). Lev-AI: n = 425,366 (A), 389,020 (U), 352,821 (C), and 380,397 (G). Lev-AI + Competitor: n = 423,930 (A), 389,653 (U), 354,014 (C), and 377,073 (G).
Extended Data Fig. 6 Plots comparing the structural fingerprints (Open Babel descriptors) of HCQ, Lev, and Das to an acquired list of FDA-approved small-molecule drugs (2076 drugs).
Open Babel descriptors are abonds (Number of aromatic bonds), atoms (Number of atoms), bonds (Number of bonds), dbonds (Number of double bonds), HBA1 (Number of Hydrogen Bond Acceptors 1), HBA2 (Number of Hydrogen Bond Acceptors 2), HBD (Number of Hydrogen Bond Donors), logP (Octanol/water partition coefficient), MR (Molar refractivity), MW (Molecular Weight), nF (Number of Fluorine Atoms), sbonds (Number of single bonds), tbonds (Number of triple bonds), and TPSA (Topological polar surface area).
Extended Data Fig. 7 qPCR independently validates the transcriptome interactions of Hydroxychloroquine (HCQ) and Dasatinib (Das) at several transcriptome binding sites in HEK293 cells.
a, Workflow showing the strategies of validating competable 2´-OH acylation sites with qPCR (Top panel). b-c, qPCR validated and quantified the relative level of 2´-OH acylation at the drug-binding loci of HCQ (b) and Das (c). Data represent mean ± s.e.m., n = 3 biologically independent experiments. Statistical significance was calculated with two-tailed Student’s t-tests: *P < 0.05, **P < 0.01, ****P < 0.0001. P values are <0.0001 (ANKRD28), 0.0198 (ATP4A), 0.0011 (ATP5PB), and 0.0254 (FAM168A), respectively.
Supplementary information
Supplementary Information
Supplementary Figs. 1–3, Tables 1–4, detailed experimental protocol, bioinformatics codes and compound characterization data.
Supplementary Tables
Tanimoto coefficient of small-molecule drugs with known RNA binders, a list of known FDA-approved RNA binders, lists of RBRP results and lists of primers used in this study.
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Fang, L., Velema, W.A., Lee, Y. et al. Pervasive transcriptome interactions of protein-targeted drugs. Nat. Chem. 15, 1374–1383 (2023). https://doi.org/10.1038/s41557-023-01309-8
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DOI: https://doi.org/10.1038/s41557-023-01309-8
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