5-fluorouracil and Rumex obtusifolius extract combination trigger A549 cancer cell apoptosis: uncovering PI3K/Akt inhibition by in vitro and in silico approaches

Abstract

Abstract The continuous increase in cancer rates, failure of conventional chemotherapies to control the disease, and excessive toxicity of chemotherapies clearly demand alternative approaches. Natural products contain many constituents that can act on various bodily targets to induce pharmacodynamic responses. This study aimed to explore the combined anticancer effects of Rumex obtusifolius (RO) extract and the chemotherapeutic agent 5-fluorouracil (5-FU) on specific molecular targets involved in cancer progression. By focusing on the PI3K/Akt signaling pathway and its related components, such as cytokines, growth factors (TNFa, VEGFa), and enzymes (Arginase, NOS, COX-2, MMP-2), this research sought to elucidate the molecular mechanisms underlying the anticancer effects of RO extract, both independently and in combination with 5-FU, in non-small lung adenocarcinoma A549 cells. The study also investigated the potential interactions of compounds identified by HPLC/MS/MS of RO on PI3K/Akt in the active site pocket through an in silico analysis. The ultimate goal was to identify potent therapeutic combinations that effectively inhibit, prevent or delay cancer development with minimal side effects. The results revealed that the combined treatment of 5-FU and RO demonstrated a significant reduction in TNFa levels, comparable to the effect observed with RO alone. RO modulated the PI3K/Akt pathway, influencing the phosphorylated and total amounts of these proteins during the combined treatment. Notably, COX-2, a key player in inflammatory processes, substantially decreased with the combination treatment. Caspase-3 activity, indicative of apoptosis, increased by 1.8 times in the combined treatment compared to separate treatments. In addition, the in silico analyses explored the binding affinities and interactions of RO's major phytochemicals with intracellular targets, revealing a high affinity for PI3K and Akt. These findings suggest that the combined treatment induces apoptosis in A549 cells by regulating the PI3K/Akt pathway.