Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu, China.
Biochem Biophys Res Commun. 2012 May 11;421(3):462-7. doi: 10.1016/j.bbrc.2012.04.012. Epub 2012 Apr 7.
The aim of the current study is to investigate the effect of ceramides on genistein-induced anti-melanoma effects in vitro. We found that exogenously added cell-permeable short-chain ceramides (C6) dramatically enhanced genistein-induced growth inhibition and apoptosis in cultured melanoma cells. Genistein treatment only induced a moderate intracellular ceramides accumulation in B16 melanoma cells. Two different agents including 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), a ceramide glucosylation inhibitor, and the sphingosine kinase-1 (SphK1) inhibitor II (SKI-II), a sphingosine (ceramides precursor) phosphorylation inhibitor, both facilitated genistein-induced ceramides accumulation and melanoma cell apoptosis. Co-administration of ceramide (C6) and genistein induced a significant Akt inhibition and c-jun-NH(2)-kinase (JNK) activation, caspase-3 cleavage and cytochrome c release. Caspase-3 inhibitor z-DVED-fmk, JNK inhibitor SP 600125, or to restore Akt activation by introducing a constitutively active form of Akt (CA-Akt) diminished ceramide (C6) and genistein co-administration-induced in vitro anti-melanoma effect. Our study suggests that increasing cellular level of ceramides may sensitize genistein-induced anti-melanoma effects.
本研究旨在探讨神经酰胺对染料木黄酮诱导体外抗黑色素瘤作用的影响。我们发现，细胞通透的短链神经酰胺（C6）可显著增强染料木黄酮诱导的培养黑色素瘤细胞生长抑制和凋亡。染料木黄酮处理仅在 B16 黑色素瘤细胞中诱导中等程度的细胞内神经酰胺积累。两种不同的试剂，包括神经酰胺葡糖基转移酶抑制剂 1-苯基-2-癸酰氨基-3-吗啉-1-丙醇（PDMP）和鞘氨醇激酶-1（SphK1）抑制剂 II（SKI-II），一种鞘氨醇（神经酰胺前体）磷酸化抑制剂，均促进了染料木黄酮诱导的神经酰胺积累和黑色素瘤细胞凋亡。神经酰胺（C6）和染料木黄酮联合给药可显著抑制 Akt 并激活 c-jun-NH(2)-kinase（JNK），导致 caspase-3 切割和细胞色素 c 释放。Caspase-3 抑制剂 z-DVED-fmk、JNK 抑制剂 SP 600125 或通过引入组成型激活形式的 Akt（CA-Akt）恢复 Akt 激活，均可减弱神经酰胺（C6）和染料木黄酮联合给药诱导的体外抗黑色素瘤作用。本研究表明，增加细胞内神经酰胺水平可能会增强染料木黄酮诱导的抗黑色素瘤作用。
