A novel reactive turn-on probe capable of selective profiling and no-wash imaging of Bruton's tyrosine kinase in live cells

Abstract

A series of reaction-based probes have been developed by conjugation of maleimide–coumarin into ibrutinib. The resulting probes display high sensitivity and selectivity toward BTK, and were proven to be suitable for simultaneous protein labeling and no-wash imaging of BTK inside live mammalian cells.

Chemical Probes and Activity-Based Protein Profiling for Cancer Research

“…To detect HER1/HER2 expression, Cy3-AFTN and Cy5-AFTN dual-targeting probes were developed to facilitate the diagnostic imaging of cancer cells in vivo ( Figure 3 ) [ 17 ]. Similarly, to enable targeting of the B cell receptor (BCR) signaling mediator Bruton’s tyrosine kinase, a dual-purpose probe, IB-4, with both imaging and inhibitory activities, was developed [ 18 ].…”

Recent advances in construction of small molecule-based fluorophore-drug conjugates

“…Recently, Li and co-workers [ 32 ] reengineered an ibrutinib analogue IB-4 ( 5, Fig. 3 D) by incorporating maleimide-coumarin moiety.…”

Applications of Activity‐Based Protein Profiling (ABPP) and Bioimaging in Drug Discovery

“…[40] Wang et al recently developed an ovel reaction-based turn-on probe capable of no-wash imaging of BTK in live cells with high sensitivity and selectivity by conjugation of maleimidecoumarin with ibrutinib (Figure 3, IB-4). [25] In this case, the turnon fluorescence difference caused by competition with drug candidates can be detectedi na384-wellp late, allowing screening of potential drugs in ah igh throughput format. This novel strategy is applicable to other irreversible inhibitors possessing ana menable a,b-unsaturatedamide moiety.…”

“…This type of turn-on probe can be used in real-time imaging to study the expression and functiono ft arget proteins,a nd has the potential of applications with variousi rreversible inhibitors ( Figure 1D). [25] Structure activity relationships (SAR) andc ocrystal structures of drug-target complexes are usually examined and used to support the design of activity-based probes. Introduction of a linker into parental inhibitors usually minimally compromises the bioactivity of the inhibitor.…”

“…In addition, a novel reactive turn‐on probe produced by coupling of maleimide‐coumarin with alkyne was successfully applied to studies of ibrutinib. This type of turn‐on probe can be used in real‐time imaging to study the expression and function of target proteins, and has the potential of applications with various irreversible inhibitors (Figure D) …”