RESUMEN
Spisulosine (1-deoxysphinganine) is a sphingoid amino alcohol isolated from the sea clams that showed potent antiproliferative activity against a broad spectrum of solid tumors but failed in clinical trials due to neurotoxicity. However, its structural similarity to other bioactive sphingoids, interesting mode of action, and appreciable potency against cancer cells make it a suitable lead for future anticancer drug development. The present study was conducted to elucidate mechanisms of the antiproliferative/cytotoxic effects of newly synthesized spisulosine analog homospisulosine (KP7). The evaluation was performed on cervical carcinoma cells, representing an in vitro model of one of the most common cancer types and a significant worldwide cause of women's cancer mortality. Treatment with homospisulosine (2.0 µM) for 24, 48, and 72 h significantly inhibited the growth of HeLa cells in vitro and induced apoptosis detectable by DNA fragmentation, externalization of phosphatidylserine, dissipation of mitochondrial membrane potential, activation of caspase-3 and cleavage of PARP. In addition, treating HeLa cells with spisulosine increased p27 and Bcl-2 on protein levels and phosphorylation of Bcl-2 on Ser70 residue. These results support the potential for spisulosine analogs represented here by homospisulosine for future therapeutic development.
Asunto(s)
Antineoplásicos , Carcinoma , Femenino , Humanos , Células HeLa , Regulación hacia Arriba , Fosforilación , Apoptosis , Antineoplásicos/farmacologíaRESUMEN
BACKGROUND/AIM: A series of experiments on HeLa cells were conducted to provide new information concerning the anti-cancer properties of jaspine B hydrochloride (JBH). MATERIALS AND METHODS: HeLa cells treated with 0.5 µmol/l JBH for 24, 48, and 72 h underwent flow cytometric analysis of the cell cycle, and measurement of phosphatidylserine externalization, mitochondrial membrane potential (MMP), casp-3 activation, cleavage of PARP, ceramide levels, aSMase activity, and Bcl-2 release. nSMase activity was measured by a colorimetric assay. Gene expression was determined by qRT-PCR. Immunocytochemistry was performed to detect p21 and p27 expression. RESULTS: JBH-induced apoptosis in HeLa cells associated with externalization of phosphatidylserine, reduced MMP, activation of casp-3, and cleavage of PARP as well as up-regulation of TNF-α, FasL, and casp-8. Significant increase in nSMase activity, ceramide levels, Bcl-2 release (predominantly in the inactive form), and pro-apoptotic nuclear localization of p21 and p27 were also detected. CONCLUSION: JBH-induced apoptosis in HeLa cells is associated with disrupted sphingolipid homeostasis resulting in increased ceramide levels.
Asunto(s)
Apoptosis/efectos de los fármacos , Ceramidas/metabolismo , Esfingolípidos/metabolismo , Esfingosina/análogos & derivados , Proliferación Celular/efectos de los fármacos , Células HeLa , Humanos , Transducción de Señal/efectos de los fármacos , Esfingosina/farmacologíaRESUMEN
In the present study, we investigated antiproliferative activity of seven newly synthesized chalcone derivatives. Among tested compounds, (2â¯E)-3-(acridin-9-yl)-1-(2,6-dimethoxyphenyl)prop-2-en-1-one (1C) was the most potent with IC50â¯=â¯4.1⯵mol/L in human colorectal HCT116â¯cells and was selected for further studies. Inhibition of cell proliferation was associated with cell cycle arrest in G2/M phase and dysregulation of α, α1 and ß5 tubulins. Moreover, 1C caused disruption of the mitochondrial membrane potential and increased number of cells with sub G0/G1 DNA content which is considered as marker of apoptosis. Apoptosis was confirmed by annexin V/PI and AO/PI staining. Furthermore, we found increased concentration of cytochrome c, Smac/Diablo and increased caspase-3 and caspase-9 activity, cleavage of PARP as well as activation of DNA repair mechanisms in 1C-treated HCT116 cancer cells. Moreover this chalcone derivative up-regulated proapoptotic Bax expression and down-regulated antiapoptotic Bcl-2 and Bcl-xL expression. Additionally, 1C treatment led to modulation of MAPKs and Akt signalling pathways. In conclusion, our data showed ability of 1C to suppress cancel cell growth and provide the rationale for further in vivo study.