These results indicate that curcumin has direct antiangiogenic activity in vitro and in vivo. The activity of curcumin in inhibiting carcinogenesis in diverse organs such as the skin and colon may be mediated in part through angiogenesis inhibition.

In response to appropriate stimulation, T lymphocytes from systemic lupus erythematosus (SLE) patients exhibit increased and faster intracellular tyrosine phosphorylation and free calcium responses. We have explored whether the composition and dynamics of lipid rafts are responsible for the abnormal T cell responses in SLE. SLE T cells generate and possess higher amounts of ganglioside-containing lipid rafts and, unlike normal T cells, SLE T cell lipid rafts include FcRγ and activated Syk kinase. IgM anti-CD3 Ab-mediated capping of TCR complexes occurs more rapidly in SLE T cells and concomitant with dramatic acceleration of actin polymerization kinetics. The significance of these findings is evident from the observation that cross-linking of lipid rafts evokes earlier and higher calcium responses in SLE T cells. Thus, we propose that alterations in the lipid raft signaling machinery represent an important mechanism that is responsible for the heightened and accelerated T cell responses in SLE.

Commercial grade curcumin (approximately 77% curcumin, 17% demethoxycurcumin and 3% bisdemethoxycurcumin) is widely used as a yellow coloring agent and spice in foods. In the present study topical application of commercial grade curcumin, pure curcumin or demethoxycurcumin had an equally potent inhibitory effect on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced increases in ornithine decarboxylase activity and TPA-induced tumor promotion in 7,12-dimethylbenz[a]anthracene-initiated mouse skin. Bisdemethoxycurcumin and tetrahydrocurcumin were less active. In additional studies we found that commercial grade curcumin, pure curcumin, demethoxycurcumin and bisdemethoxycurcumin had about the same potent inhibitory effect on TPA-induced inflammation of mouse ears, as well as TPA-induced transformation of cultured JB6 (P+) cells. Tetrahydrocurcumin was less active. The results indicate that pure curcumin and demethoxycurcumin (the major constituents of commercial grade curcumin) have the same potent inhibitory effects as commercial grade curcumin for inhibition of TPA-induced tumor promotion, but bisdemethoxycurcumin and tetrahydrocurcumin are less active.

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Objective. T cells from a majority of patients with systemic lupus erythematosus (SLE) display antigen receptor-mediated signaling aberrations associated with defective T cell receptor (TCR) chain, a subunit of the TCR/CD3 complex. This study was undertaken to explore the possibility that forced expression of TCR chain may reverse the known signaling abnormalities and defective interleukin-2 (IL-2) production in SLE T cells.Methods. Freshly isolated SLE T cells were transfected with TCR chain construct in a eukaryotic expression vector at high efficiency, by a recently developed nucleoporation technique. Restoration of TCR/ CD3-mediated signaling was studied in the chaintransfected cells.Results. In SLE T cells transfected with TCR chain, surface expression of TCR chain was increased and the TCR/CD3-induced increased free intracytoplasmic calcium concentration response was normalized, as was hyperphosphorylation of cellular substrates. Simultaneously, the previously noted increased expression of the Fc receptor ␥ chain was diminished in SLE T cells transfected with the chain expression vector, and the surface membrane clusters of cell signaling molecules were redistributed to a more continuous pattern. TCR chain replacement also augmented the expression of diminished TCR/CD3-mediated IL-2 production in SLE T cells, associated with increased expression of the p65 subunit of nuclear factor B in the nuclear fractions of these T cells. Conclusion. These results suggest that reconstitution of deficient TCR chain can reverse the TCR/ CD3-mediated signaling abnormalities as well as the defective IL-2 production in T cells of patients with SLE.It is well recognized that T cells from patients with systemic lupus erythematosus (SLE) display a number of signaling abnormalities (1). Many of the identified molecular aberrations explain certain established cell and cytokine defects, whereas the mechanisms of other defects have not yet been elucidated. Our group and others have demonstrated that the expression of the subunit of the T cell receptor (TCR) is decreased in a majority of SLE patients (2-4) and that this defect persists over time and is independent of disease activity (5).Despite the decreased expression of the TCR chain in SLE T cells, crosslinking of the TCR/CD3 complex leads to increased free intracytoplasmic calcium concentration ([Ca 2ϩ ] i ) response (6) and protein tyrosine phosphorylation (2,4). These events appear to occur because the Fc receptor (FcR) ␥ chain becomes a functional part of the TCR/CD3 complex (7). In support