The long latency and high incidence of prostate carcinogenesis provides the opportunity to intervene with chemoprevention in order to prevent or eradicate prostate malignancies. We present here an overview of the chemopreventive potential of curcumin (diferuloylmethane), a well-known natural compound that exhibits therapeutic promise for prostate c...
The deregulated activation of NF-kappaB is associated with cancer development and inflammatory diseases. With an aim to find new NF-kappaB inhibitors, we purified and characterized compounds from extracts of the Fijian sponge Rhabdastrella globostellata, the crinoid Comanthus parvicirrus, the soft corals Sarcophyton sp. nov. and Sinularia sp., and ...
A strong relationship exists between inflammation and carcinogenesis. To bring insights into the anti-inflammatory mechanisms by which chemopreventive agents, such as curcumin, are able to counteract the action of inflammation mediators, such as tumor necrosis factor-alpha (TNF-alpha), we compared gene expression profiles in K562 cells treated with...
We have previously shown that oxidative stress induced by an apoptogenic dose of H2O2 leads to a temporary block of glycolytic flux via inactivation of the glycolytic key enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in U937 cells. This corresponds to the activation of a cell defense pathway that is triggered to repair stress-induced dama...
Curcumin, a natural product isolated from the plant Curcuma longa, has a diverse range of molecular targets that influence numerous biochemical and molecular cascades. Curcumin has been shown to inhibit nuclear factor kappaB (NF-kappaB) activation at several steps in the NF-kappaB signaling pathways and thereby controls numerous NF-kappaB-regulated...
We have shown that melatonin exerts a prooxidant activity in U937 cells, a tumor human promonocytic cell line. (1) Here we show that melatonin induces a strong canonical activation of NF-kappaB, inducing IkappaBalpha degradation and the consequential nuclear translocation of p50/p65 subunits. The timing of NF-kappaB activation overlaps with the tim...
Three new compounds of the rare classes trisnorditerpenes, bisnorditerpenes, and norditerpenes, gracilins J-L (1, 2, 6), and a new diterpene, 3'-norspongiolactone (8), were isolated from the extract of the marine sponge Spongionella sp. using NMR- and bioassay-guided fractionation, in addition to three known gracilins (3-5) as well as the known dit...
Heat shock response is an adaptive response, which helps the cells to regulate their physiological homeostasis under stress. Here we show that the natural compound curcumin induces nuclear translocation of the heat shock transcription factor (HSF)-1, its binding to a heat shock regulatory element (HSE), and the subsequent activation of the hsp70 pr...
The decision of a cell to die is triggered by the imbalance between the positive signals, those needed for continuing to survive (i.e. growth factors), and negative signals (i.e. DNA damages, increased levels of oxidants) [1]. There are two major mechanisms of cell death: necrosis and apoptosis. The severity of the injury leads the cells to decide ...
Erythropoiesis is considered as a multistep and tightly regulated process under the control of a series of cytokines including erythropoietin (Epo). Epo activates specific signaling pathways and leads to activation of key transcription factors such as GATA-1, in order to ensure erythroid differentiation. Deregulation leads to a decreased number of ...