Novel erbium complex with anticancer activity against radiation resistant lung adenocarcinoma cells

In this work, novel erbium complex with anticancer activity against radiation resistant lung adenocarcinoma cells was obtained and demonstrated. Firstly, stronger inhibitory effect of Er³⁺ on non-small cell lung cancer (NSCLC) cells and NSCLC- radiation resistant (RR) cells was experimentally confirmed. Then, by selecting highly biocompatible porphyrins as ligands, a novel erbium complex tetraphenylporphyrin erbium acetylacetonate (Er(acac)TPP) was synthesized and purified. Compared with Cisplatin, notably, Er(acac)TPP exhibits relatively higher inhibitory efficiency on NSCLC-RR cells. Moreover, the toxicities of Er(acac)TPP to normal cells are much lower than that of cancer cells. Subsequently, cell expansion, increased apoptosis, a decline in mitochondrial membrane potential (MMP), an accumulation of intracellular reactive oxygen species (ROS), increased Caspase-9 protein level and G2/M arrest were seen. These data all pointed to Er(acac)TPP as a possible candidate for more research and development as a chemotherapeutic drug.