Product Description

EGFR (T790M, L858R) is a compound mutant form of the epidermal growth factor receptor (EGFR), a member of the receptor tyrosine kinase (RTK) family that plays a pivotal role in cell proliferation, survival, differentiation, and tumorigenesis. This double mutation combines the activating L858R mutation in the kinase domain—a common driver in non‑small cell lung cancer (NSCLC)—with the secondary T790M “gatekeeper” mutation, which typically emerges as an acquired resistance mechanism following treatment with first‑ and second‑generation EGFR tyrosine kinase inhibitors (TKIs). The T790M mutation restores ATP affinity while reducing binding of reversible TKIs, thereby conferring resistance while maintaining ligand‑independent oncogenic signaling through pathways such as MAPK and PI3K/AKT. Beyond its role in mediating acquired drug resistance, dysregulation of EGFR (T790M, L858R) signaling is a critical determinant of sensitivity to third‑generation EGFR TKIs (such as osimertinib), making it a highly validated target for overcoming therapeutic resistance and guiding precision cancer therapy.

Screeningbio’s EGFR (T790M, L858R) Kinase Assay Kit provides a robust, sensitive, and high-throughput platform for quantifying EGFR (T790M, L858R)  kinase activity and evaluating the potency of tyrosine kinase inhibitors (TKIs).

This kit utilizes the ADP-Glo Kinase Assay platform, a luminescent technology that measures the amount of ADP produced during the kinase reaction.

The assay is performed in two distinct steps:

1. Kinase Reaction: EGFR (T790M, L858R)  catalyzes the transfer of a phosphate group from ATP to a specific substrate, resulting in the production of phosphorylated substrate and ADP.

2. ADP-Glo™ Reagent Addition: After the kinase reaction, the ADP-Glo™ Reagent is added to terminate the reaction and deplete any remaining unreacted ATP.

3. Kinase Detection: The Kinase Detection Reagent is added to simultaneously convert the produced ADP back into ATP, which is then used by luciferase to generate a luminescent signal.

The light intensity produced is directly proportional to the ADP concentration and, consequently, to the enzymatic activity of the EGFR (T790M, L858R)  kinase.