Autophagy is a lysosomal degradation and recycling process involved in tumor progression and drug resistance. The aim of this work was to inhibit autophagy and increase apoptosis in a 3D model of human colorectal cancer by combined treatment with our patented natural product Prunus spinosa + nutraceutical activator complex (PsT + NAC®) and 5-fluorouracil (5-FU). By means of cytotoxic evaluation (MTT assay), cytofluorimetric analysis, light and fluorescence microscopy investigation and Western blotting evaluation of the molecular pathway PI3/AKT/mTOR, Caspase-9, Caspase-3, Beclin1, p62 and LC3, we demonstrated that the combination PsT + NAC® and 5-FU significantly reduces autophagy by increasing the apoptotic phenomenon. These results demonstrate the importance of using non-toxic natural compounds to improve the therapeutic efficacy and reduce the side effects induced by conventional drugs in human colon cancer.
Keywords: 5-fluorouracil; Prunus spinosa; apoptosis; autophagy; colorectal cancer; drug resistance; spheroids.