Estudios científicos
The sphingosine kinase-1 survival pathway is a molecular target for the tumor-suppressive tea and wine polyphenols in prostate cancer
Abstract:
The sphingosine kinase-1/sphingosine 1-phosphate (SphK1/S1P) pathway has been associated with cancer promotion and progression and resistance to treatments in a number of cancers, including prostate adenocarcinoma. Here we provide the first evidence that dietary agents, namely, epigallocatechin gallate (EGCg, IC50 approximately 75 muM), resveratrol (IC50 approximately 40 muM), or a mixture of polyphenols from green tea [polyphenon E (PPE), IC50 approximately 70 muM] or grapevine extract (vineatrol, IC50 approximately 30 muM), impede prostate cancer cell growth in vitro and in vivo by inhibiting the SphK1/S1P pathway. We establish that SphK1 is a downstream effector of the ERK/phospholipase D (PLD) pathway, which is inhibited by green tea and wine polyphenols. Enforced expression of SphK1 impaired the ability of green tea and wine polyphenols, as well as pharmacological inhibitors of PLD and ERK activities, to induce apoptosis in PC-3 and C4-2B cells. The therapeutic efficacy of these polyphenols on tumor growth and the SphK1/S1P pathway were confirmed in animals using a heterotopic PC-3 tumor in place model. PC-3/SphK1 cells implanted in animals developed larger tumors and resistance to treatment with polyphenols. Furthermore, using an orthotopic PC-3/GFP model, the chemopreventive effect of an EGCg or PPE diet was associated with SphK1 inhibition, a decrease in primary tumor volume, and occurrence and number of metastases. These results provide the first demonstration that the prosurvival, antiapoptotic SphK1/S1P pathway represents a target of dietary green tea and wine polyphenols in cancer.-Brizuela, L., Dayon, A., Doumerc, N., Ader, I., Golzio, M., Izard, J.-C., Hara, Y., Malavaud, B., Cuvillier, O. The sphingosine kinase-1 survival pathway is a molecular target for the tumor-suppressive tea and wine polyphenols in prostate cancer.
Comentarios divulgativos:
Las rutas metabólicas asociadas a las enzimas esfingosina kinasa-1 y esfingosina-1 fosfato se han sido implicadas con la progresión y la resistencia a los tratamientos de gran número de cánceres incluido el adecarcinoma de próstata.
En este estudio se evidencia que compuestos presentes en la dieta como una mezcla de polifenoles provenientes del te verde así como del extracto de uvas impiden tanto estudios in vivo como in vitro al crecimiento de células cancerígenas inhibiendo las rutas metabólicas sphK1/S1P
