Discovery and optimization of 4-anilinoquinazoline derivatives spanning ATP binding site and allosteric site as...

Area of Science:

• Oncology
• Medicinal Chemistry
• Molecular Biology

Background:

• Epidermal growth factor receptor (EGFR) is a key target in non-small cell lung cancer (NSCLC) treatment.
• Tertiary mutations like C797S in EGFR confer resistance to third-generation inhibitors by disrupting drug binding.
• Developing novel inhibitors effective against these resistance mutations is crucial for improving patient outcomes.

Purpose of the Study:

• To design and synthesize novel 4-anilinoquinazoline derivatives targeting the ATP binding pocket and allosteric site of EGFR.
• To evaluate the efficacy of these compounds against EGFR-C797S resistance mutations in vitro and in vivo.
• To identify potent inhibitors for overcoming acquired resistance in NSCLC.

Main Methods:

• Design and synthesis of a series of 4-anilinoquinazoline derivatives.
• In vitro anti-proliferative assays using BaF3 cells with specific EGFR mutations (L858R/T790M/C797S and 19del/T790M/C797S).
• Western blot analysis to assess inhibition of EGFR and downstream signaling pathways.
• In vivo efficacy study using a BaF3-EGFR^{19del/T790M/C797S} xenograft mouse model.

Main Results:

• The synthesized 4-anilinoquinazoline derivatives showed high potency against EGFR-C797S resistance mutations.
• Compound 14d exhibited significant anti-proliferative effects against BaF3-EGFR^{L858R/T790M/C797S} (IC50 = 0.75 μM) and BaF3-EGFR^{19del/T790M/C797S} (IC50 = 0.09 μM) cells.
• Compound 14d demonstrated dose-dependent inhibition of EGFR and its downstream signaling pathways.
• In vivo studies showed that 14d significantly inhibited tumor growth in the xenograft model (TGI = 67.95% at 30 mg/kg).

Conclusions:

• Compound 14d is a novel and effective inhibitor of EGFR-C797S, targeting both the ATP binding pocket and the allosteric site.
• 14d demonstrates potent anti-cancer activity both in vitro and in vivo, suggesting its potential as a therapeutic agent for NSCLC with acquired resistance.
• These findings provide a promising new avenue for treating NSCLC patients who have developed resistance to existing EGFR inhibitors.