Synergistic effect of Dactolisib/Lys05 combination on autophagy in A549 cells

Abstract

Effective therapeutic strategies are urgently required to enhance the prognosis of patients suffering from KRAS mutations. Owing to the undruggable nature of KRAS, targeting downstream signaling pathways, namely PI3K/AKT/mTOR, shows antiproliferative and apoptotic effects. Unfortunately, targeting this pathway upregulates autophagy, contributing to reduced drug efficacy. Therefore, it was reasonable to use a combination of kinase inhibitors and autophagy inhibitors to achieve a higher therapeutic benefit. The impact of Dactolisib, a dual PI3K/mTOR inhibitor, and Lys05, a dimeric chloroquine, was tested on the survival of breast cancer MCF-7 and lung cancer A549 cells. The dose selection for the optimal effect of the Dactolisib/Lys05 combination was determined using CompuSyn software. This combinatorial effect was evaluated using various methodologies, such as expression profile analysis for autophagic, proliferative, and apoptotic markers. These effects were corroborated by ELISA, Western blot, and flow cytometry using the Annexin V-FITC apoptosis detection kit. A549 cells treated in a 2:1 ratio of Lys05 and Dactolisib demonstrated a synergistic effect on cell death, proliferation, and apoptotic gene markers, in addition to its effect on autophagic gene and protein markers, showing an enhanced effect compared to monotherapy. Therefore, the PI3K/AKT kinase inhibitor/autophagy inhibitor combination establishes higher therapeutic benefits on A549 cells compared to kinase inhibitor monotherapy.