A novel dihydroacridine derivative targets epidermal growth factor receptor-expressing cancer cells in vitro and in vivo.

Small molecules are considered a source of novel medicines targeting carcinogenic intracellular pathways including epidermal growth factor receptor (EGFR) signaling. The main goal of the study is to assess whether LHT-17-19 could be considered an effective target molecule against EGFR-expressing tumor cells in silico, in vitro, and in vivo. This was an in vivo, ex vivo, and in vivo experimental study. LHT-17-19 affinity to EGFR's kinase domain was assessed by the ligand's molecular docking. EGFR-expressing Hs746T human gastric cancer cell culture and patient-derived organoid (PDO) model of EGFR-positive breast cancer (BC) were used for in vitro assessment of the molecule anticancer property. IC₅₀ and GI₅₀ indexes were estimated using MTT- and MTS-based tests, respectively. Anticancer activity of LHT-17-19 against EGFR-expressing mutant lung carcinoma was studied on patient-derived xenograft (PDX) model established in 10 humanized BALB/c male mice. Continuous variables were presented as a mean ± standard deviation. Intergroup differences were assessed by two-way t-test. Kaplan-Meier's curves were used for survival analysis. High affinity of LHT-17-19 for the EGFR kinase domain with dG score -7.9 kcal/mol, EDoc-5.45 kcal/mol, and Ki 101.24 uM was due to intermolecular π-σ bonds formation and the ligand intramolecular transformation. LHT-17-19 induced anti-EGFR-expressing gastric cancer cells cytotoxicity with IC₅₀ 0.32 µM (95% confidence interval [CI] 0.11-0.54 µM). The derivative inhibited growth of EGFR-expressing BC PDO with GI₅₀ 16.25 µM (95% CI 4.44-28.04 µM). 2 mg/kg LHT-17-19 intravenously daily during 7 days inhibited PDX tumor growth and metastatic activity, prolonged animals' survival, and eliminated EGFR-mutant lung cancer cells from residual tumor's node. LHT-17-19 may be considered a molecular platform for further search of promising molecules, EGFR-expressing cancer cell inhibitors.