n-caproylsphingosine and Melanoma

Considering that tumor development is generally multifactorial, therapy with a combination of agents capable of potentiating cytotoxic effects is promising. In this study, we co-encapsulated C6 ceramide (0.35%) and paclitaxel (0.50%) in micro and nanoemulsions containing tributyrin (a butyric acid pro-drug included for potentiation of cytotoxicity), and compared their ability to co-localize the drugs in viable skin layers. The nanoemulsion delivered 2- and 2.4-fold more paclitaxel into viable skin layers of porcine skin in vitro at 4 and 8h post-application than the microemulsion, and 1.9-fold more C6 ceramide at 8h. The drugs were co-localized mainly in the epidermis, suggesting the nanoemulsion ability for a targeted delivery. Based on this result, the nanoemulsion was selected for evaluation of the nanocarrier-mediated cytotoxicity against cells in culture (2D model) and histological changes in a 3D melanoma model. Encapsulation of the drugs individually decreased the concentration necessary to reduce melanoma cells viability to 50% (EC

Topics: Animals; Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Cell Survival; Ceramides; Drug Carriers; Emulsions; Melanoma; Nanoparticles; Paclitaxel; Skin; Skin Absorption; Swine; Triglycerides

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.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Proliferation; Ceramides; Drug Resistance, Neoplasm; Enzyme Activation; Genistein; Humans; MAP Kinase Kinase 4; Melanoma; Melanoma, Experimental; Mice; Morpholines; Thiazoles

The majority of metastatic melanomas are resistant to diverse chemotherapeutic agents, and long-term survival for patients with melanoma who have metastatic disease is dismal. Consequently, the search for novel anti-melanoma agents is urgent. Here, we evaluate the potential effects of C6 ceramide to sensitize melanoma cell lines (B16 and WM-115 cells) to curcumin-induced cell death.. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used to test melanoma cell viability in vitro. Hoechst 33342 fluorescence and Histone DNA ELISA was used to evaluate melanoma cell apoptosis. Apoptosis-associated proteins in melanoma cells after treatments were measured by Western blot.. C6 ceramide promotes curcumin-induced cell death and apoptosis in B16 and WM-115 melanoma cell lines. Curcumin itself promotes pro-apoptosis protein Caspase 3 and Caspase 9 cleavage and anti-apoptosis protein Bcl-XL and X-IAP degradation, and combination of C6 ceramide with curcumin dramatically enhances it. Caspase inhibitors largely inhibit C6-ceramide plus curcumin induced cell death and apoptosis.. We suggest that C6 ceramide sensitizes melanoma cell to curcumin induced cell death and apoptosis in vitro, which is due to, at least in part, the augment of mitochondria apoptosis pathway. Combining C6 ceramide with traditional chemotherapy drugs such as curcumin may have potential to be used as a new therapeutic intervention against melanoma.

Topics: Animals; Antineoplastic Agents; Apoptosis; Caspase 3; Caspase 9; Cell Death; Cell Line, Tumor; Ceramides; Curcumin; Drug Synergism; Humans; Melanoma; Mice; Mitochondria

We evaluated the cytotoxic effects of a cell-permeable ceramide (Cer), N-hexanoyl-D-sphingosine (C6-Cer) and of two related sphingoid bases, sphingosine (So) and dihydrosphingosine (sphinganine; Sa) on human melanoma cell lines and on soft tissue sarcoma lines recently established from fresh surgical biopsy specimens. These cell lines ranged from high susceptibility (939 melanoma) to strong resistance (A2058 melanoma and all three sarcomas) to tumour necrosis factor (TNF), an inducer of elevated intracellular Cer levels. However, all the cell lines demonstrated a dose-dependent susceptibility to C6-Cer with protracted cytotoxic kinetics, with the C8161 melanoma being the most sensitive and A2058 the least. Protein kinase C (PKC) antagonizes Cer-dependent apoptosis, and chelerythrine chloride, So and Sa, which inhibit PKC, caused extremely rapid cytotoxicity of melanoma cell lines, irrespective of their relative sensitivity to C6-Cer. So-mediated cytotoxicity was extensive even after only 90 min of treatment, within the time frame of limb perfusion. So and Sa only slightly potentiated the cytotoxic responses to TNF, C6-Cer or melphalan. Sphingolipid-driven intracellular pathways may offer opportunities for therapy of these tumours.

Topics: Alkaloids; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Benzophenanthridines; Carboxylic Acids; Cell Survival; Ceramides; Dose-Response Relationship, Drug; Fumonisins; Histiocytoma, Benign Fibrous; Humans; Lung Neoplasms; Melanoma; Melphalan; Phenanthridines; Protein Kinase C; Sarcoma; Signal Transduction; Sphingosine; Time Factors; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha