Zuo Jin Wan formula inhibits cisplatin-resistance of gastric cancer cells via mitochondrial translocation of cofilin-1

OBJECTIVE Despite the status of cisplatin(DDP) as a classical chemotherapeutic agent in the treatment of cancer,the development of multidrug resistance often leads to a failure of DDP therapy.Traditional Chinese medicine(TCM) as adjuvant chemotherapy of cancer drugs in China has been widely used in cancer treatment.ZuoJin WAN(ZJW),a TCM formula,was proved reversing drug resistance in gastric cancer,but its exact mechanism was still unclear.METHODS CCK-8 assay was used to detect the cell viability.The levels of proteins and mRNA were evaluated using Western blot and q-PCR.Mitochondrial membrane potential was measured by flow cytometry.Depolymerisa.tion of F-actin and translocation of G-actin(gamma-actin) from the cytoplasm to the mitochondria was detected using an immuno fl uorescence assay.RESULTS phosphorylated coflin-1(p-coflin-1) was overexpressed in the DDP-resistant human gastric cancer cell lines SGC7901/DDP and BGC823/DDP,relative to the respective parent cell lines(SGC7901 and BGC823),and DDP induced the dephosphory.lation of p-coflin-1 in both parent lines but not in the DDP-resistant lines.However,ZJW could induce the dephosphorylation of pcoflin-1 and promote coflin-1 translocation from the cytoplasm into the mito.chondria in both SGC7901/DDP and BGC823/DDP cells.This mitochondrial translocation of coflin-1 was found to induce the conversion of flamentous actin to globular-actin,activate mitochondrial dam.age and calcium overloading,and induce the mitochondrial apoptosis pathway.These effects of ZJW on DDP-resistant human gastric cancer cell lines could be reversed via transfection with coflin-1-specifc siRNA,or treatment with a PP1 and PP2A inhibitor.CONCLUSION ZJW can be used as an inhibitor of chemoresistance in gastric cancer,which may partly be due to dephosphorylation of p-coflin-1 via the activation of PP1 and PP2A.