<i>In vitro</i> evaluation of cytotoxic and mutagenic activity of avarol

<p>The cytotoxicity of avarol, a main secondary metabolite of the Mediterranean sponge <i>Dysidea avara</i>, was <i>in vitro</i> screened by MTT assay against four human tumour cell lines. The colon HT-29 tumour cells practically showed to be the only sensitive ones towards this organic compound. No toxicity was found against the fetal lung fibroblast MRC-5 cells at the concentrations tested. In comparison with doxorubicin, used as a positive control, avarol actually exhibited at least 588-fold less toxicity towards normal MRC-5 cells. Finally, comet assay indicated that DNA fragmentation was almost fivefold higher upon the treatment with doxorubicin, compared to avarol. The obtained results have actually confirmed that avarol scaffold may contribute to development of new cytostatics inspired by nature.</p

Effect of SC and CSP on DNA fragmentation.

<p>The T47D cells were treated with SC (10 µg/ml), CSP (10 µg/ml) or Dauno (100 µM) for 24 h, thereafter DNA fragmentation was analyzed by comet assay (A), agarose gel electrophoresis (B) and diphenylamine assay (C). Basal DNA damage from untreated cells, DNA damage from SC or CSP cells (A). Data are from a single experiment and representative of 50 randomly selected cells stained with ethidium bromide (EtBr). Data illustrated in (B) are from a single experiment and representative of three separate experiments, while data in (C) are expressed as mean ± S.E.M. of three separate experiments. ***p<0.001 <i>vs.</i> control (untreated cells).</p

Effect of SC and CSP on p50 and p65 nuclear translocation.

<p>Representative Western blot of p50 and p65 as well as the densitometric analysis shows p50 and p65 nuclear translocation in T47D cells incubated with CSP (10 µg/ml) or SC (10 µg/ml) for 24 h. The results are from a single experiment and are representative of three separate experiments. Densitometric data are expressed as mean ± S.E.M. of three separate experiments. ***p<0.001 <i>vs</i>. untreated cells. The expression of GAPDH is shown as an equal loading control.</p

Effect of SC and CSP on apoptosis induction.

<p>Detection of dead and dying cells by FACS (A). Cells treated overnight with SC, CSP and cisPt were stained with ΔΨ_m-sensitive dye DiOC₆(3) and the vital dye propidium iodide (PI). The white portions of the columns refer to the DiOC₆(3)^low/PI⁺ population (dead) and the remaining part of the column corresponds to the DiOC₆(3)^low/PI^- (dying) population. Results are means ± S.E.M. of three independent experiments. Expression profile of apoptosis-related proteins (B). Cell lysates from HeLa cells, treated with SC (10 µM) and CSP (10 µM) overnight, were analyzed by human apoptosis profiler. Data are expressed as means ± S.D. of two independent experiments.</p

Cacospongionolide and Scalaradial: structures and original sponges.

<p>Chemical structures of cacospongionolide and scalaradial isolated from marine sponges <i>Fasciospongia cavernosa</i> and <i>Cacospongia scalaris</i>, respectively.</p