Advancing apoptosis induction in triple negative breast cancer: Empowering treatment with tyrosine-stapled mixed micelles of lapatinib

Abstract

The available treatment modalities for triple-negative breast cancer (TNBC) face several challenges, including discouraging overall survival outcomes, unavoidable toxicities, and the emergence of drug resistance. Further, there is an amplified requirement for various amino acids to support the uncontrolled proliferation of TNBC. Hence, targeted therapy for enhancing the treatment of TNBC was explored which encompassed hydrophobized (using α-linolenic acid) Pluronic-based mixed micelles having inherent L-type/Large neutral amino acid transporter 1 targeting (tyrosine-stapled) ability (LPT T-MM). LPT T-MM had optimal size (142.34 ± 30.23 nm), polydispersity index (0.224 ± 0.01), and enhanced drug loading capacity (∼10 %). Transmission electron microscopy confirmed their spherical shape. In vitro release studies showed sustained drug release without hemolysis risk. LPT T-MM had higher cellular uptake and cytotoxicity than free LPT. IC50 values for LPT T-MM were significantly reduced in MDA-MB-231 (∼1.64-fold) and 4 T1 (∼1.88-fold) cell lines; apoptosis index was superior in MDA-MB-231 (∼2.04-fold) and 4 T1 cell line (∼2.09-fold) compared to free LPT. LPT T-MM generated more reactive oxygen species and caused mitochondrial membrane depolarization, indicating increased cell death by apoptosis. Thus, LPT T-MM had the ability to promote apoptosis, showed promise in enhancing the payload capabilities and targeting in TNBC.