Cinnamic acid induces apoptotic cell death and cytoskeleton disruption in human melanoma cells

Anticancer activities of cinnamic acid derivatives include induction of apoptosis by irreversible DNA damage leading to cell death. The present work aimed to compare the cytotoxic and genotoxic potential of cinnamic acid in human melanoma cell line (HT-144) and human melanocyte cell line derived from blue nevus (NGM). Viability assay showed that the IC50 for HT-144 cells was 2.4 mM, while NGM cells were more resistant to the treatment. The growth inhibition was probably associated with DNA damage leading to DNA synthesis inhibition, as shown by BrdU incorporation assay, induction of nuclear aberrations and then apoptosis. The frequency of cell death caused by cinnamic acid was higher in HT-144 cells. Activated-caspase 3 staining showed apoptosis after 24 hours of treatment with cinnamic acid 3.2 mM in HT-144 cells, but not in NGM. We observed microtubules disorganization after cinnamic acid exposure, but this event and cell death seem to be independent according to M30 and tubulin labeling. The frequency of micronucleated HT-144 cells was higher after treatment with cinnamic acid (0.4 and 3.2 mM) when compared to the controls. Cinnamic acid 3.2 mM also increased the frequency of micronucleated NGM cells indicating genotoxic activity of the compound, but the effects were milder. Binucleation and multinucleation counting showed similar results. We conclude that cinnamic acid has effective antiproliferative activity against melanoma cells. However, the increased frequency of micronucleation in NGM cells warrants the possibility of genotoxicity and needs further investigation.

Nevo de células fusiformes de Reed na conjuntiva

Os autores relatam um caso de nevo de Reed, lesão que apresenta aspecto histológico de malignidade, mas tem evolução benigna. Paciente de 48 anos, masculino, cor parda, apresentava pterígio nasal no olho direito, associado a uma lesão pequena e pouco pigmentada localizada na cabeça do mesmo. Realizou-se exérese de ambos, sem intercorrências, sem sinais de recidiva. O exame histopatológico revelou lesão com bordas definidas, restrita ao epitélio, constituída por células fusiformes perpendiculares à superfície, com pigmentação melânica esparsa. O diagnóstico inicial foi nevo de Spitz, mas, posteriormente, chegou-se à conclusão que se tratava do nevo de células fusiformes de Reed. O presente relato é o segundo na literatura mundial e o primeiro no Brasil.