RESUMEN
Resistance to cisplatin (DDP)-based chemotherapy is a major cause of treatment failure in human gastric cancer (GC). It is necessary to identify the drugs to re-sensitize GC cells to DDP. In our previous research, Zuo Jin Wan Formula (ZJW) has been proved could increase the mitochondrial apoptosis via cofilin-1 in a immortalized cell line, SGC-7901/DDP. Due to the immortalized cells may still difficult highly recapitulate the important molecular events in vivo, primary GC cells model derived from clinical patient was constructed in the present study to further evaluate the effect of ZJW and the underlying molecular mechanism. Immunofluorescent staining was used to indentify primary cultured human GC cells. Western blotting was carried out to detect the protein expression. Cell Counting Kit-8 (CCK-8) was used to evaluate cell proliferation. Flow cytometry analysis was performed to assess cell apoptosis. ZJW inhibited proliferation and induced apoptosis in primary DDP-resistant GC cells. Notably, the apoptosis in GC cells was mediated by inducing cofilin-1 mitochondrial translocation, down-regulating Bcl-2 and up-regulating Bax expression. Surprisingly, the level of p-AKT protein was higher in DDP-resistant GC cells than that of the DDP-sensitive GC cells, and the activation of AKT could attenuate ZJW-induced sensitivity to DDP. These data revealed that ZJW can increase the chemosensitivity in DDP-resistant primary GC cells by inducing mitochondrial apoptosis and AKT inactivation. The combining chemotherapy with ZJW may be an effective therapeutic strategy for GC chemoresistance patients.
Asunto(s)
Cisplatino/uso terapéutico , Cofilina 1/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cisplatino/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Células Tumorales CultivadasRESUMEN
Gastric cancer (GC) is the third leading cause of cancer-related death. Chemotherapy resistance remains the major reason for GC treatment failure and poor overall survival of patients. Our previous studies have proved that Zuo Jin Wan (ZJW), a traditional Chinese medicine (TCM) formula, could significantly enhance the sensitivity of cisplatin (DDP)-resistant gastric cancer cells to DDP by inducing apoptosis via mitochondrial translocation of cofilin-1. However, the underlying mechanism remains poorly understood. This study aimed to evaluate the effects of ROCK/PTEN/PI3K on ZJW-induced apoptosis in vitro and in vivo. We found that ZJW could significantly activate the ROCK/PTEN pathway, inhibit PI3K/Akt, and promote the apoptosis of SGC-7901/DDP cells. Inhibition of ROCK obviously attenuated ZJW-induced apoptosis as well as cofilin-1 mitochondrial translocation, while inhibition of PI3K had the opposite effects. In vivo, combination treatment of DDP and ZJW (2000 mg/kg) significantly reduced tumor growth compared with DDP alone. Moreover, the combined administration of ZJW and DDP increased the expression of cleaved ROCK and p-PTEN while it decreased p-PI3K and p-cofilin-1, which was consistent with our in vitro results. These findings indicated that ZJW could effectively inhibit DDP resistance in GC by regulating ROCK/PTEN/PI3K signaling and provide a promising treatment strategy for gastric cancer.
RESUMEN
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. Here we found that phosphorylated cofilin-1 (p-cofilin-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 that DDP induced the dephosphorylation of p-cofilin-1 in both parent lines but not in the DDP-resistant lines. However, we noted that the traditional Chinese medicine formula Zuo Jin Wan (ZJW) could induce the dephosphorylation of p-cofilin-1 and promote cofilin-1 translocation from the cytoplasm into the mitochondria in both SGC7901/DDP and BGC823/DDP cells. This mitochondrial translocation of cofilin-1 was found to induce the conversion of filamentous actin to globular-actin, activate mitochondrial damage and calcium overloading, and induce the mitochondrial apoptosis pathway. We further observed that these effects of ZJW on DDP-resistant human gastric cancer cell lines could be reversed via transfection with cofilin-1-specific siRNA, or treatment with a PP1 and PP2A inhibitor. These results suggest that ZJW is an effective drug therapy for patients with DDP-resistant gastric cancer.
RESUMEN
A traditional Chinese medicine (TCM) formula, Zuo Jin Wan (ZJW), has been found as an anticancer drug in human cancer. In this study, we investigated the synergistic effect of ZJW extracts on DDP-induced apoptosis in human gastric cancer SGC-7901/DDP cells. Our results demonstrated that ZJW extracts could increase the sensitivity of SGC-7901/DDP cells to DDP by increasing the concentration of DDP in cytoplasm and enhance the proapoptosis of DDP by upregulating the JNK and Bax expression, downregulating the Bcl-2 expression, increasing the accumulation of Cytochrome C in cytoplasm, and promoting the activities of caspase-3 and caspase-9. In vivo, ZJW extracts enhanced the inhibiting effect of DDP on tumor growth in SGC-7901/DDP xenograft model and upregulated the expression of p-JNK and Bax but downregulated the Bcl-2 expression in xenograft tumors. In conclusion, in vitro and in vivo, ZJW extracts could enhance the proapoptotic effect of DDP by promoting the activation of JNK and the expression of Bcl-2, inhibiting the Bax expression, followed by increasing the release of Cytochrome C from mitochondria to cytoplasm, and finally activating the caspase cade reaction. Our results implied that ZJW might serve as a synergistic drug with chemotherapeutic drugs DDP in the treatment of gastric cancer.