RESUMEN
Esophageal carcinoma (EsC) is a clinically challenging neoplastic disease. Genistein, a natural isoflavone product, has anti-tumor properties. Through in vitro and in vivo studies, we found that genistein suppressed EsC cell proliferation in a time- and concentration-dependent manner. In addition, genistein markedly promoted apoptosis and arrested cell cycle at the G0/G1 phase in a concentration-dependent manner. Furthermore, high concentrations of genistein have no adverse effect on normal esophageal epithelial cells. Mechanistically, genistein treatment strikingly reduced the expression of cell cycle-associated genes, and up-regulated the expression of cell apoptosis-related genes in EsC cells. Additionally, genistein dramatically decreased epidermal growth factor receptor (EGFR) expression and attenuated its down-stream signaling molecules STAT3, MDM2, Akt and JAK1/2 phosphorylation, resulting in inhibited nuclear translocation of STAT3 and MDM2, thereby inhibiting the JAK1/2-STAT3 and AKT/MDM2/p53 signaling pathways. In xenograft nude mice, genistein administration strikingly impaired tumor growth in a dose-dependent manner. Moreover, similar disturbances in molecular mechanisms were observed in vivo. Taken together, genistein suppressed the JAK1/2-STAT3 and AKT/MDM2/p53 signaling pathways by decreasing EGFR expression, leading to cell apoptosis, cell cycle arrest, and proliferation inhibition in EsC cells. Our findings suggest that genistein may be a promising alternative adjuvant therapy for patients with EsC.
Asunto(s)
Carcinoma , Neoplasias Esofágicas , Genisteína/farmacología , Janus Quinasa 1/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Factor de Transcripción STAT3/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/efectos de los fármacos , Carcinoma/tratamiento farmacológico , Carcinoma/metabolismo , Carcinoma/patología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Humanos , Ratones , Fitoestrógenos/farmacología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Euphorbia factor L1 (EFL1) belongs to diterpenoids of genus Euphorbia. In this article, its reversal activity against ABCB1-mediated MDR in KBv200 and MCF-7/adr cells was reported. However, EFL1 did not alter the sensitivity of KB and MCF-7 cells to chemotherapeutic agents. Meanwhile, EFL1 significantly increased accumulation of doxorubicin and rhodamine 123 in KBv200 and MCF-7/adr cells, showing no significant influence on that of KB and MCF-7 cells. Furthermore, EFL1 could enhance the ATP hydrolysis activity of ABCB1 stimulated by verapamil. At the same time, EFL1 inhibited the efflux of ABCB1 in KBv200 and MCF-7/adr cells. In addition, EFL1 did not downregulate expression of ABCB1 in KBv200 and MCF-7/adr cells either in mRNA or protein level.