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- Prostate cancer: antitumor effect of chalcones on androgen dependent and androgen-independent prostate cancer cell linesPublication . Horta, Bruno; Cerqueira, Fátima; Pinto, Madalena; Cidade, Honorina; Silva, Jani; Pereira, António; Medeiros, R.
- 1,2-dihydroxyxanthone: effect on A375-C5 melanoma cell growth associated with interference with THP-1 human macrophage activityPublication . Silva, Viviana; Cerqueira, Fátima; Nazareth, Nair; Medeiros, R.; Sarmento, Amélia; Sousa, Emília; Pinto, MadalenaXanthones have been suggested as prospective candidates for cancer treatment. 1,2- dihydroxyxanthone (1,2-DHX) is known to interfere with the growth of several cancer cell lines. We investigated the effects of 1,2-DHX on the growth of the A375-C5 melanoma cell line and THP-1 human macrophage activity. 1,2-DHX showed a moderate growth inhibition of A375-C5 melanoma cells (concentration that causes a 50% inhibition of cell growth (GI50) = 55.0 ±2.3 µM), but strongly interfered with THP-1 human macrophage activity. Supernatants from lipopolysaccharide (LPS)-stimulated THP-1 macrophage cultures exposed to 1,2-DHX significantly increased growth inhibition of A375-C5 cells, when compared to supernatants from untreated LPS-stimulated macrophages or to direct treatment with 1,2-DHX only. 1,2-DHX decreased THP-1 secretion of interleukin-1β (IL-1β) and interleukin-10 (IL-10), but stimulated tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1) production. This xanthone also inhibited nitric oxide (NO) production by RAW 264.7 murine macrophages, possibly through inhibition of inducible NO synthase production. In conclusion, these findings suggest a potential impact of 1,2-DHX in melanoma treatment, not only due to a direct effect on cancer cells but also by modulation of macrophage activity.
- Inhibitory effect of 5-aminoimidazole-4-carbohydrazonamides derivatives against Candida spp. biofilm on nanohydroxyapatite substratePublication . Gabriel, C.; Grenho, L.; Cerqueira, Fátima; Medeiros, R.; Dias, A. M.; Ribeiro, A. I.; Proença, M. F.; Fernandes, M. H.; Sousa, J. C.; Monteiro, F. J.; Ferraz, M. P.Candida can adhere and form biofilm on biomaterials commonly used in medical devices which is a key attribute that enhances its ability to cause infections in humans. Furthermore, biomaterial-related infections represent a major therapeutic challenge since Candida biofilms are implicated in antifungal therapies failure. The goals of the present work were to investigate the effect of three 5-aminoimidazole-4-carbohydrazonamides, namely (Z)-5-amino-1-methyl-N'-aryl-1H-imidazole-4-carbohydrazonamides [aryl = phenyl (1a), 4-fluorophenyl (1b), 3-fluorophenyl (1c)], on Candida albicans and Candida krusei biofilm on nanohydroxyapatite substrate, a well-known bioactive ceramic material. To address these goals, both quantitative methods (by cultivable cell numbers) and qualitative evaluation (by scanning electron microscopy) were used. Compounds cytocompatibility towards osteoblast-like cells was also evaluated after 24 h of exposure, through resazurin assay. The three tested compounds displayed a strong inhibitory effect on biofilm development of both Candida species as potent in vitro activity against C. albicans sessile cells. Regarding cytocompatibility, a concentration-dependent effect was observed. Together, these findings indicated that the potent activity of imidazole derivatives on Candida spp. biofilms on nanohydroxyapatite substrate, in particular compound 1c, is worth further investigating.
- Effect of heptaphylline and two related secondary metabolites on cervical (HeLa) and prostate (LNCaP and PC-3) cancer cell linesPublication . Horta, Bruno; Cerqueira, Fátima; Pinto, Madalena; Sousa, Emília; Puthongking, Ploenthip; Pereira, António; Medeiros, R.