The Analysis of the PI3K-AKT-mTOR Pathway and Mitochondria Modulation by a 2-Aminopyridine Compound Using the Metastatic Prostate Cancer Cell Line PC-3

Background: Prostate cancer is one of the most prevalent and deadly neoplasias in the male population. Despite the availability of therapies that increase the long-term survival of patients with localized tumors, metastatic prostate cancer is challenging to treat. A previous study revealed that the 2-aminopyridine derivative (named Neq0440) inhibited the PI3K-AKT-mTOR pathway and presented selective cytotoxicity toward the metastatic prostate cancer cell line PC-3. Methods: Here, we further analyzed the mechanism of action of these molecules by using cell-based colorimetric, fluorometric, epifluorescence microscopy, and Western blot assays. Results: Mitochondrial depolarization increased the AMPK level at 24 h inhibition with Neq0440, which led to the PI3K-AKT-mTOR pathway downregulation after 48 h. The phosphorylation was inhibited for AKT and the downstream quinases (S6RP and 4EBP1) from the PI3K-AKT-mTOR pathway, which can work together with the mitochondrial depolarization, lowering the pH of the medium, increasing ROS levels, and translocating the lysosomes toward the nucleus to trigger cell death. Conclusions: Therefore, Neq0440 can be used as a lead compound to obtain derivatives with a novel anticancer mechanism of action.