Structure–Activity and Cationic Amphiphilic Drug-like Behavior of Aromatic Triamino Glycosylated Antitumor Ether Lipids with Cytotoxicity in 2D and 3D Models

This study reports the synthesis, cytotoxic evaluation, and mechanistic insights of an amphiphilic triamino glycosylated antitumor ether lipid (GAEL). A series of aryl-substituted tricationic d-galacto-GAELs were synthesized to mimic cationic amphiphilic drug (CAD)-like structural characteristics. Among the series, the quinoline-bearing triamino GAEL (compound <b>17</b>) exhibited the highest cytotoxicity in 2D cultures against drug-sensitive and drug-resistant ovarian, breast, pancreatic, liver, prostate, and brain cancer cells, completely eliminating all cells, whereas cisplatin and doxorubicin were less effective. GAEL <b>17</b> also demonstrated superior efficacy in an SK-OV-3 3D tumor spheroid model, fully disintegrating spheroids and inducing cell death at concentrations ≥25 μM. In contrast, doxorubicin reduced viability but did not eradicate spheroids at 50 μM, likely due to slower drug action or limited penetration over 48 h exposure. GAEL <b>17</b> retained caspase-independent, non-apoptotic cell death. LysoTracker assay indicated lysosomal disruption, while LipidTOX staining showed dose-dependent fluorescence, consistent with CAD-like lipid accumulation.