Communication
ChemComm
pathogenesis by binding to TPP1. Our study might provide a
new mechanism, different from tyrosine kinase inhibition, for
nintedanib’s role in the treatment of IPF, lung carcinoma and
other diseases.
We greatly acknowledge the Funding provided by Drug
Innovation Major Project (2018ZX09711001-011) and the CAMS
Innovation Fund for Medical Sciences (CIFMS) (Grant No. 2016-
I2M-3-010).
Conflicts of interest
There are no conflicts to declare.
Notes and references
1 J. Taeger, C. Moser and C. Hellerbrand, et al., Mol. Cancer Ther.,
2011, 10, 2157–2167.
2 N. Stjepanovic and J. Capdevila, Biol.: Targets Ther., 2014, 8,
129–139.
3 M. Kudo, R. S. Finn and S. Qin, et al., Lancet, 2018, 391, 1163–1173.
4 A. M. Pick and K. K. Nystrom, Clin. Ther., 2012, 34, 511–520.
5 M. Røed Skårderud, A. Polk and K. Kjeldgaard Vistisen, et al., Cancer
Treat. Rev., 2018, 62, 61–73.
Fig. 4 (A) Cellular thermal shift assay (CETSA) using HUVEC intact cells
after treatment of NDNB (10 mM) or DMSO control. (B) Telomerase activity
analysis using a telomeric repeat amplification protocol (TRAP) assay after
treatment of NDNB in HUVECs for 24 h. Heat-inactivated (HI) lysates and
lysis buffer (LB) were used as negative controls. PC: positive control,
NDNB: nintedanib.
immunofluorescence staining procedure, so it does not affect
confocal studies.
To further confirm the direct binding interaction of TPP1
with nintedanib, we performed a cellular thermal shift assay
(CETSA) to profile whether the thermal stability of TPP1 could
be enhanced by treatment of nintedanib. Because the for-
6 G. J. Roth, R. Binder and F. Colbatzky, et al., J. Med. Chem., 2015, 58,
1053–1063.
.pdf, accessed Mar. 16, 2020.
9 S. Rangarajan, A. Kurundkar and D. Kurundkar, et al., Am. J. Respir.
Cell Mol. Biol., 2016, 54, 51–59.
mation of a ligand–protein complex could increase the protein 10 W. T. Tai, C. W. Shiau and Y. S. Li, et al., J. Hepatol., 2014, 61, 89–97.
stability.24 It demonstrated that 10 mM of nintedanib effectively
11 N. Nishijima, M. Seike and C. Soeno, et al., Int. J. Oncol., 2016, 48,
937–944.
decreased the temperature-dependent degradation of TPP1
¨
12 J. Lehmann, J. Richers, A. Pothig and S. A. Sieber, Chem. Commun.,
compared with the control group (Fig. 4A), suggesting that
TPP1 is the target engaged by nintedanib in intact cells.
Ultimately, with the aim of understanding the functional meaning
of nintedanib–TPP1 interaction, we performed a telomeric repeat
amplification protocol (TRAP) assay since the function of TPP1
was closely linked to telomerase activity and IPF disease.22 This
result showed that nintedanib significantly inhibited the telomerase
activity does-dependently in HUVECs (Fig. 4B). Hence, nintedanib
may decrease the telomerase activity by interacting with TPP1,
thereby exerting its therapeutic effects.
In summary, we designed and synthesized a variety of
structurally diversified and clickable probes based on the SAR
of nintedanib, and obtained active photoaffinity probe P3. Then
we identified one of the highly reliable binding proteins of
nintedanib associated with telomeres by a chemoproteomic
strategy, and further validated TPP1 as one of the direct targets
possibly responsible for nintedanib’s pleiotropic effects. Func-
tionally, nintedanib can significantly inhibit telomerase activity
that is reported to have close ties with cell proliferation and IPF
2017, 53, 107–110.
13 X. Cheng, L. Li, M. Uttamchandani and S. Q. Yao, Chem. Commun.,
2014, 50, 2851–2853.
14 L. Li, C. W. Zhang and J. Ge, et al., Angew. Chem., Int. Ed., 2015, 54,
10821–10825.
15 K. Yamaura, K. Kuwata and T. Tamura, et al., Chem. Commun., 2014,
50, 14097–14100.
16 J. Dai, K. Liang and S. Zhao, et al., Proc. Natl. Acad. Sci. U. S. A., 2018,
115, E5896–E5905.
17 H. Guo, J. Xu, P. Hao, K. Ding and Z. Li, Chem. Commun., 2017, 53,
9620–9622.
18 H. C. Kolb, M. G. Finn and K. B. Sharpless, Angew. Chem., Int. Ed.,
2001, 40, 2004–2021.
19 P. Kleiner, W. Heydenreuter, M. Stahl, V. S. Korotkov and
S. A. Sieber, Angew. Chem., Int. Ed., 2017, 56, 1396–1401.
20 G. J. Roth, A. Heckel and F. Colbatzky, et al., J. Med. Chem., 2009, 52,
4466–4480.
21 F. Hilberg, G. J. Roth and M. Krssak, et al., Cancer Res., 2008, 68,
4774–4782.
22 F. L. Zhong, L. F. Z. Batista and A. Freund, et al., Cell, 2012, 150,
481–494.
23 B. Englinger, S. Kallus and J. Senkiv, et al., J. Exp. Clin. Cancer Res.,
2017, 36, 122.
24 R. Jafari, H. Almqvist and H. Axelsson, et al., Nat. Protoc., 2014, 9,
2100–2122.
This journal is © The Royal Society of Chemistry 2021
3142 | Chem. Commun., 2021, 57, 3139–3142